25(OH)D levels during the COVID-19 pandemic: impact of lockdown and ultraviolet radiation.

BACKGROUND: Home confinement policies during the COVID-19 pandemic limited sun exposure and may have influenced on vitamin D levels. OBJECTIVE: To assess changes in 25(OH)D during the COVID-19 pandemic and the impact of Mandatory Preventive Social Isolation (MPSI) on UV radiation recommended dose modified by clouds for the synthesis of vitamin D (UVDVC). MATERIAL AND METHODS: A retrospective study was carried out on 15,908 patients in whom the level of 25(OH)D was determined between January 2019 and December 2021 in a centralized laboratory in Rosario, Argentina. RESULTS: Lower levels of 25(OH)D were documented in people younger than 40 years during 2020, as well as a variation during the pandemic period, with lower values in the first wave. Lower levels of 25(OH)D were recorded in the post-MPSI period in comparison with the MPSI period (p < 0.00001), in addition to a higher frequency of hypovitaminosis D (48.6% vs. 36.1%). These differences were not observed in the comparison of the same periods of 2019. UVDVC did not vary between 2019 and 2020. CONCLUSIONS: The restrictions due to the COVID-19 pandemic led to a higher frequency of hypovitaminosis D and lower frequency of optimal values.

ANTECEDENTES: Las políticas de confinamiento domiciliario durante la pandemia de COVID-19 limitaron la exposición solar y pudieron influir en los niveles de vitamina D. OBJETIVO: Evaluar los cambios en 25(OH)D durante la pandemia de COVID-19 y el impacto del aislamiento social, preventivo y obligatorio (ASPO) en la dosis recomendada de radiación UV modificada por las nubes para la síntesis de vitamina D (UVDVC). MATERIAL Y MÉTODOS: Se realizó un estudio retrospectivo de 15 908 pacientes en quienes se determinó el nivel de 25(OH)D entre enero de 2019 y diciembre de 2021 en un laboratorio centralizado en Rosario, Argentina. RESULTADOS: Se constataron niveles más bajos de 25(OH)D en menores de 40 años durante 2020, así como una variación durante el período pandémico, con menores valores en la primera ola. Se registraron menores niveles de 25(OH)D en el período posterior al ASPO en comparación con el período de ASPO (p < 0.00001), además de mayor frecuencia de hipovitaminosis D (48.6 % versus 36.1 %). No se observaron estas diferencias en la comparación de los mismos períodos de 2019. La UVDVC no varió entre 2019 y 2020. CONCLUSIONES: Las restricciones por la pandemia de COVID-19 llevaron a mayor frecuencia de hipovitaminosis D y menor frecuencia de valores óptimos.

Association between vitamin D serum levels and inflammatory markers in patients on hemodialysis.

INTRODUCTION: The relationship between 25-OH-vitamin D and the immune system in patients with chronic kidney disease is a subject of attention. OBJECTIVES: To assess the prevalence of vitamin D deficiency in patients on hemodialysis and to investigate the association between vitamin D, ultra-sensitive C-reactive protein (US-CRP), neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR). METHOD: Cross-sectional study of 80 patients on hemodialysis, divided into two groups: a serum 25-OH-vitamin D level < 20 ng/mL was considered to be vitamin D deficiency and a serum level ≥ 20 ng/mL was regarded as normal. The relationship between the parameters was defined with Spearman's correlation analysis. RESULTS: 40 % of the patients had vitamin D deficiency. There were significant differences between groups in US-CRP (p = 0.047), NLR (p = 0.039), PLR (p = 0.042) and treatment with vitamin D analogues (p = 0.022). Vitamin D had a significant negative correlation with US-CRP (p = 0.026), NLR (p = 0.013) and PLR (p = 0.022). CONCLUSIONS: The prevalence of vitamin D deficiency was 40 %. The values of US-CRP, NLR and PLR were significantly higher in the presence of vitamin D deficiency. A significant inverse correlation was found between vitamin D levels and US-CRP, NLR and PLR. INTRODUCCIÓN: La relación entre 25-OH-vitamina D y el sistema inmune en pacientes con enfermedad renal crónica es objeto de atención. OBJETIVOS: Evaluar la prevalencia de la deficiencia de vitamina D en pacientes en hemodiálisis e investigar la asociación entre la vitamina D y proteína C reactiva ultrasensible (PCRus), índice neutrófilo-linfocito (INL) e índice plaqueta-linfocito (IPL). MÉTODO: Estudio transversal de 80 pacientes en hemodiálisis, divididos en dos grupos: un nivel sérico de 25-OH-vitamina D < 20 ng/mL se consideró como deficiencia de vitamina D y ≥ 20 ng/mL, como normal. Con el análisis de correlación de Spearman se definió la relación entre los parámetros. RESULTADOS: 40 % de los pacientes presentó deficiencia de vitamina D. Hubo diferencias significativas entre los grupos en PCRus (p = 0.047), INL (p = 0.039), IPL (p = 0.042) y tratamiento con análogos de vitamina D (p = 0.022). La vitamina D tuvo una correlación negativa significativa con PCRus (p = 0.026), INL (p = 0.013) e IPL (p = 0.022). CONCLUSIONES: La deficiencia de vitamina D fue de 40 %. Los niveles de PCRus, INL e IPL fueron significativamente más altos ante deficiencia de vitamina D. Se encontró correlación inversa significativa entre vitamina D y PCRus, INL e IPL.

[Severe vitamin D deficiency in children from Punta Arenas, Chile: Influence of nutritional status on the response to supplementation]. / Deficiencia severa de vitamina D en niños de Punta Arenas, Chile: influencia de estado nutricional en la respuesta a suplementación.

UNLABELLED: There is a high risk of vitamin D (VD) deficiency in the population of southern Chile that can be treated with VD supplements. Weight excess (WE) can influence the response to supplements. OBJECTIVES: To study the prevalence of VD deficiency and the effect of cholecalciferol (VD3) supplements in healthy children from Punta Arenas, Chile, and evaluate a possible association with nutritional status. METHODOLOGY: Demographic and anthropometric data, as well as laboratory assessment of serum 25-hidroxyvitamin D (25OHD) and other bone metabolism parameters were evaluated. After baseline evaluation, children were supplemented with VD3 1600 IU/day for one month, after which 25OHD was retested. RESULTS: Of the 108 children studied, 50% were boys, and had a mean age of 9.6±0.5 years. Nutritional assessment showed that 39% had normal weight, 46% were overweight, and 15% were obese. Median 25OHD was 10.9ng/ml: 96.3% had deficiency (<20ng/ml) and 3.7% insufficiency (20-29ng/ml). Severe deficiency was found in 62% (<12ng/ml). Baseline 25OHD was not affected by nutritional status. After supplementation, median 25OHD was 17.5ng/ml: 62% had deficiency, 36% insufficiency, and 2% sufficiency (>30ng/ml). Children with WE had a significantly lower increase in 25OHD than children with normal weight (5±5.5 vs. 7.7±4.9, p=03). Children with WE may require 32% higher VD dose than normal weight children to attain the same 25OHD concentration. CONCLUSIONS: Chilean schoolchildren from Punta Arenas have high prevalence of WE and VD deficiency, with a majority in the range of severe VD deficiency. WE interferes in the response to VD supplementation, leading to a lower increase in 25OHD.

Risk of vitamin D deficit in asthmatic children hospitalized in the north area of Santiago.

Introduction: Introduction: in recent years asthma hospitalization rate in Chilean children has doubled. Numerous studies have shown an association between hypovitaminosis D and frequent, severe asthmatic exacerbations in children. Objective: to estimate the risk of vitamin D (vitD) deficiency and insufficiency in hospitalized asthmatic children compared with patients who are monitored on an outpatient basis and do not have records of hospitalization in one year. Material and methods: an observational, analytic, and case-control study carried out in one calendar year including asthmatic children between 5 and 15 years of age. This study registered: sociodemographic and clinical data, asthma control test, severity score of hospitalization and measurements of vitD blood levels. Associations between variables were analyzed using the t-test and chi-squared test. The risk for hypovitaminosis D and deficiency was calculated through logistic regression. The data was fed into the Stata 14 software. Results: a total of 117 patients, 9 ± 2.7 years old, were admitted, 64 % were male and 51 % presented with malnutrition by excess. Six out of ten children presented moderate asthma and 55 % had a poor control of their pathology; 73.5 % presented hypovitaminosis D (insufficiency and deficiency), hospitalized patients had 2.8 times more risk of presenting vitD deficiency, adjusted according to seasonality and age (95 %CI, 1.07-7.5, p < 0.05) without being associated with a higher severity score of hospitalization. Conclusion: Most of the asthmatic children in the sample presented with hypovitaminosis D, with a higher percentage of deficiency in hospitalized patients, which is not associated with greater severity of hospitalization.

Introducción: Introducción: la tasa de hospitalización por asma se ha duplicado en los últimos años en Chile. Numerosos estudios demuestran una asociación entre la hipovitaminosis D y la presencia de exacerbaciones frecuentes y severas. Objetivo: comparar el riesgo de déficit e insuficiencia de vitamina D (vitD) en niños asmáticos que se hospitalizan en relación con los que se tratan ambulatoriamente. Material y métodos: estudio observacional, analítico, de casos y controles realizado durante 1 año calendario. Se incluyó a pacientes asmáticos de 5 a 15 años. Se registraron datos sociodemográficos, clínicos, nivel de control de asma, puntaje de severidad de hospitalización y se midió la concentración sanguínea de vitD. Se analizó la asociación entre las variables mediante la prueba de la t y la del chi cuadrado. Mediante regresión logística se calculó el riesgo de hipovitaminosis D y déficit de vitD en los sujetos. Los datos se analizaron con el software Stata 14. Resultados: se enrolaron 117 pacientes de 9 ± 2,7 años, 64 % de varones y 51 % con malnutrición por exceso. Seis de cada diez niños presentaban asma moderada y el 55 % tenían mal control de su enfermedad. El 73,5 % de los sujetos presentaban hipovitaminosis D (déficit o insuficiencia). Los hospitalizados tuvieron 2,8 veces más riesgo de presentar déficit de vitD (IC 95 %: 1,07-7,5), ajustado según estacionalidad y edad, sin asociarse a mayor puntaje de severidad de la hospitalización. Conclusión: la mayoría de los niños asmáticos de la muestra presentan hipovitaminosis D, siendo mayor el porcentaje de déficit en los hospitalizados, lo que no se asocia a mayor severidad de la hospitalización.

The impact of vitamin D deficiency on clinical, biochemical and metabolic parameters in primary hyperparathyroidism.

BACKGROUND: It has been suggested that vitamin D deficiency is associated with worse clinical outcomes in primary hyperparathyroidism (PHPT). We aimed to evaluate the relationship between vitamin D deficiency and clinical, biochemical and metabolic parameters in PHPT patients. METHODS: A total of 128 patients with biochemically confirmed PHPT were included. Patients were categorized as vitamin D deficient if 25-OH vitamin D was <50nmol/L, or normal if vitamin D was ≥50nmol/L. Biochemical parameters, bone mineral densitometry (BMD), and urinary tract and neck ultrasonography were assessed. RESULTS: In the study group, 66 (51.6%) patients had vitamin D deficiency and 60 (48.4%) had normal vitamin D levels. Nephrolithiasis and osteoporosis were found in 26.6% and 30.5% of subjects, respectively. The prevalence of metabolic syndrome (MetS), obesity (BMI≥30kg/m2) and hypertension (HTN) were higher in the vitamin D deficient group when compared to the normal group (p=0.04, p=0.01 and p=0.03, respectively). There was no difference regarding the presence of nephrolithiasis and osteoporosis between the groups. The mean adenoma size was similar in both groups. CONCLUSIONS: Vitamin D deficiency was not associated with osteoporosis, nephrolithiasis, adenoma size or biochemical parameters in PHPT. However, vitamin D deficiency may be a risk factor for developing HTN and MetS in PHPT.

Severe COVID-19 patients have severe vitamin D deficiency in Northeast Mexico.

Introduction: Objective: the association between vitamin D and COVID-19 severity is not consistent. We compared prevalences and analyzed the association between vitamin D deficiency and COVID-19 severity in Northeast Mexico. Methods: this was a cross-sectional study with individuals consecutively included at a referral diagnostic center during March-September 2020 (n = 181). Concurrently, every patient admitted to intensive care was also consecutively included (n = 116). Serum 25(OH)D < 20 ng/mL was considered vitamin D deficiency. Descriptive, ANOVA, and multivariate ordinal regression analyses were performed. Results: vitamin D deficiency prevalence was 63.8 % (95 % CI, 54.7, 72.0) in severe COVID-19; 25.6 % (95 % CI, 17.4, 36.0) in mild COVID-19; and 42.4 % (95 % CI, 33.2, 52.3) in non-diseased individuals. Vitamin D deficiency increased 5 times the odds of severe COVID-19 (95 % CI, 1.1, 24.3), independently of sex, age, body mass index, and inflammatory markers. Conclusions: this study is the first report of vitamin D deficiency in Northeast Mexico. Vitamin D deficiency was associated with COVID-19 severity.

Introducción: Objetivo: la asociación entre la vitamina D y la gravedad de la COVID-19 no es consistente. Se comparó la prevalencia y se analizó la asociación de la deficiencia de vitamina D con la gravedad de los pacientes con COVID-19 en el noreste de México. Métodos: este fue un estudio transversal. Se incluyó consecutivamente a individuos de un centro de diagnóstico de referencia durante marzo-septiembre de 2020 (n = 181). Paralelamente, se reclutó a todos los pacientes que ingresaron a cuidados intensivos en ese mismo periodo (n = 116). Se consideró que había deficiencia de vitamina D ante cifras de 25(OH)D sérica < 20 ng/ml. Se realizaron un análisis descriptivo, un ANOVA y una regresión ordinal multivariante. Resultados: la prevalencia de la deficiencia de vitamina D fue del 63,8 % (IC del 95 %: 54,7; 72,0) en la COVID-19 grave, del 25,6 % (IC del 95 %: 17,4; 36,0) en la COVID-19 leve y del 42,4 % (IC del 95 %: 33,2; 52,3) sin COVID-19. La deficiencia aumentó 5 veces las probabilidades de una COVID-19 grave (IC del 95 %: 1,1; 23,9) independientemente del sexo, la edad, el índice de masa corporal y los marcadores inflamatorios. Conclusiones: este estudio es el primer informe de la deficiencia de vitamina D en el noreste de México. La deficiencia de vitamina D se asoció con la gravedad de la COVID-19.

Characterization of serum vitamin D levels in pediatric patients with chronic lymphocytic thyroiditis.

BACKGROUND: Chronic lymphocytic thyroiditis or Hashimoto's thyroiditis is the most frequent cause of acquired hypothyroidism in children. An association between low levels of 25-hydroxyvitamin D (25OH vitamin D) and the development of the disease have been detected. The aim of this study was to describe 25OH vitamin D levels in patients aged 5 to 18 years with a diagnosis of Hashimoto's thyroiditis in three pediatric endocrinology outpatient centers in Medellín, Colombia. METHODS: We conducted a cross-sectional observational study with retrospective data collection. We evaluated the sociodemographic characteristics, diagnoses, presence of comorbidities, and frequency of vitamin D deficiency. RESULTS: Sixty patients were included. The 25OH vitamin D levels were sufficient in 65% of the cases according to the Institute of Medicine (IOM) criteria and in 10% of the cases according to the Endocrine Society criteria. Serum calcium and phosphorus values were normal in 53% and 45% of the patients, respectively. All patients had normal magnesium and parathyroid hormone levels. No differences were found in the exploratory analysis when comparing 25OH vitamin D levels, thyroid antibody levels, and thyroid volume. CONCLUSIONS: In this chronic lymphocytic thyroiditis population, we did not find an increased prevalence of vitamin D deficiency according to IOM or the Endocrine Society criteria compared with previous data from the general population. No statistically significant differences were found in the exploratory analysis.

INTRODUCCIÓN: La tiroiditis linfocítica crónica o tiroiditis de Hashimoto es la causa más frecuente de hipotiroidismo adquirido en la edad pediátrica. Se ha detectado una asociación entre concentraciones bajas de 25-hidroxivitamina D (25OH vitamina D) y el desarrollo de la enfermedad. El objetivo de este trabajo fue describir las concentraciones de 25OH vitamina D en pacientes de 5 a 18 años con diagnóstico de tiroiditis linfocítica crónica en tres centros de consulta externa de endocrinología pediátrica enMedellín,Colombia. MÉTODOS: Se llevó a cabo un estudio observacional de corte transversal con recolección retrospectiva de la información. Se evaluaron características sociodemográficas, particularidades del diagnóstico, presencia de comorbilidad y frecuencia de deficiencia de vitamina D. RESULTADOS: Se incluyeron 60 pacientes. La concentración de 25OH vitamina D fue suficiente en el 65% de los casos según los criterios de Institute of Medicine (IOM) y en el 10% de los casos según los criterios de la Endocrine Society. Los valores de calcio y fósforo sérico fueron normales en el 53% y el 45% de los pacientes, respectivamente. Todos los pacientes presentaron concentraciones normales de magnesio y paratohormona. No se encontraron diferencias en el análisis exploratorio al comparar la concentración de 25OH vitamina D, de anticuerpos tiroideos y el volumen tiroideo. CONCLUSIONES: En esta población con tiroiditis linfocítica crónica no se encontró una mayor prevalencia de deficiencia de 25OH vitamina D según los criterios del IOM y de la Endocrine Society en comparación con datos previos de la población general. En el análisis exploratorio no se encontraron diferencias estadísticamente significativas.

Cardiometabolic risk factors and hypovitaminosis D in adolescents with overweight from a sunny region in northeast Brazil: a cross-sectional study.

INTRODUCTION: Background: obesity can influence vitamin D levels, which in turn might be associated with cardiometabolic risk factors. Objectives: this study assessed the association between 25-hydroxyvitamin D [25(OH)D] levels and cardiometabolic risk factors in adolescents with overweight living in a region of northeastern Brazil. Material and methods: a cross-sectional study was carried out by non-probabilistic sampling in adolescents diagnosed with overweight or obesity. The subjects were divided according to their 25(OH)D status into two groups: sufficient vitamin D and hypovitaminosis D. Biodemographic, lifestyle, cardiometabolic, and biochemical factors were evaluated. A logistic regression model was applied to determine the predictors of hypovitaminosis D. Results: we found a high frequency of hypovitaminosis D (45.6 %) in adolescents. Weekly sun exposure was negatively associated with hypovitaminosis D (OR = 0.96; 95 % CI: 0.92-0.99), while significant positive associations were observed between hypovitaminosis D and blood pressure above the 95th percentile (OR = 4.00; 95 % CI: 1.19-13.37), body weight (OR = 1.04; 95 % CI: 1.01-1.07), and fasting insulin (OR = 1.13; 95 % CI: 1.05-1.22). Conclusion: hypovitaminosis D showed a high prevalence in adolescents with overweight living in a sunny region of northeastern Brazil, and cardiometabolic risk factors such as systemic arterial hypertension, high body weight, and hyperinsulinemia are predictors of hypovitaminosis D.

INTRODUCCIÓN: Introducción: la obesidad puede influir en los niveles de vitamina D, lo que a su vez podría estar asociado con factores de riesgo cardiometabólico. Objetivos: este estudio evaluó la asociación entre los niveles de 25-hidroxivitamina D [25(OH)D] y los factores de riesgo cardiometabólico en adolescentes con sobrepeso que viven en una región del noreste de Brasil. Material y métodos: se realizó un estudio transversal mediante muestreo no probabilístico con adolescentes diagnosticados de sobrepeso u obesidad. Los sujetos se dividieron según su estado de 25(OH)D en dos grupos: suficiente vitamina D e hipovitaminosis D. Se evaluaron factores biodemográficos, de estilo de vida, cardiometabólicos y bioquímicos. Se aplicó un modelo de regresión logística para determinar los predictores de la hipovitaminosis D. Resultados: encontramos una alta frecuencia de hipovitaminosis D (45,6 %) en los adolescentes. La exposición semanal al sol se asoció negativamente a la hipovitaminosis D (OR = 0,96; IC 95 %: 0,92-0,99), mientras que se observaron asociaciones positivas significativas entre hipovitaminosis D y presión arterial por encima del percentil 95 (OR = 4,00; IC 95 %: 1,19-13,37), peso corporal (OR = 1,04; IC del 95 %: 1,01-1,07) e insulina en ayunas (OR = 1,13; IC del 95 %: 1,05-1,22). Conclusión: la hipovitaminosis D mostró una alta prevalencia entre los adolescentes con sobrepeso que viven en una región soleada del noreste de Brasil, y los factores de riesgo cardiometabólico, como hipertensión arterial sistémica, peso corporal elevado e hiperinsulinemia, son predictores de hipovitaminosis D.

Trabecular bone score and 25-hydroxyvitamin D levels in microvascular complications of type 2 diabetes mellitus. / Índice trabecular óseo y niveles de 25-hidroxivitamina D en las complicaciones microvasculares de la diabetes mellitus tipo 2.

BACKGROUND AND OBJECTIVE: Diabetic microvascular disease (MVD) has been associated with increased bone fragility. The objective was to analyse the relationship between MVD and trabecular microstructure -assessed by the trabecular bone score (TBS)- in type 2 diabetic (T2D) patients. A second aim was to know the relationship between vitamin D and MVD. PATIENTS AND METHODS: Cross-sectional study, which included men >50 years and postmenopausal women participating in a population-based cohort, diagnosed with T2D. The presence of nephropathy, neuropathy and/or retinopathy was classified as MVD+. Clinical and laboratory variables, TBS, 25(OH)D and BMD by DXA, were evaluated. Bivariate and multivariate analysis were performed. RESULTS: We evaluated 361 patients (51.1% women), 63.8 (9) years old. Of them, 92 were MVD+ and presented poorer metabolic control, longer duration of T2D, lower TBS [1.235 (.1) vs. 1.287 (.1); p=.007] and lower levels of 25(OH)D [18.3 (7) vs. 21.6 (8) ng/ml; p=.0001). There were no differences between MVD+ and MVD- with regard to BMD or P1NP and ß-CTX markers. After adjusting for confounders, including HbA1c and duration of T2D, the TBS value in MVD+ was 1.252 (95% CI 1.230-1.274) vs. 1.281 (95% CI 1.267-1.295) in MVD- (p=.034). MVD was associated with a 25(OH)D level <20 ng ml with an adjusted OR of 1.88 (95% CI 1.06-3.31; p=.028). CONCLUSIONS: The MVD+ patients presented a significantly lower TBS, after adjusting for confounders. Furthermore, multivariable analysis showed a significant relationship between a low 25(OH)D level and a prevalent MVD.

[Vitamin D insufficiency in a healthy pediatric population. The importance of early prophylaxis]. / Déficit de vitamina D en una población pediátrica sana. La importancia de una adecuada profilaxis.

INTRODUCTION: Introduction: vitamin D maintains the concentration of calcium and phosphorus within the physiological range, allowing normal metabolism and bone mineralization. Recently, vitamin D deficiency has been related not only with rickets but also with an increased risk of other pathologies. The aim of this descriptive, observational, cross-sectional study was to assess vitamin D concentration levels in a healthy pediatric population, as well as the current situation of prophylaxis. Vitamin D determination was measured by serum 25-hydroxyvitamin D (25(OH)D) concentration. Methods: a total of 258 healthy patients between 3 months and 15 years of age were enrolled (6.77 ± 3.95 years; 73.6 % were male). Results: the mean value of 25-hydroxyvitamin D was 26.60 ng/mL ± 8.02 ng/mL, and up to 20.9 % of the population showed insufficient levels. Statistically significant differences in vitamin D levels were observed between ages (p = 0.002), ethnicity groups (p = 0.038), and skin types (p = 0.000). In addition, a higher prevalence of vitamin D insufficiency in children who had never previously received vitamin D supplementation (41.6 %) was observed compared to those that had taken supplementation in the first year of life (16.7 %). Conclusion: our study shows a high prevalence of vitamin D deficiency among healthy children, and the benefit of prophylaxis with vitamin D supplementation.

INTRODUCCIÓN: Introducción: la vitamina D mantiene la concentración de calcio y fósforo dentro del rango fisiológico, permitiendo un metabolismo normal y la correcta mineralización de los huesos. Recientemente, la deficiencia de vitamina D se ha relacionado no solo con el raquitismo sino también con el aumento del riesgo de otras patologías. El objetivo de este estudio descriptivo, observacional y transversal fue conocer los niveles de concentración de vitamina D en una población pediátrica sana y la situación actual en cuanto a la profilaxis. La determinación de la vitamina D se midió mediante la concentración sérica de 25-hidroxivitamina D (25(OH)D). Material y métodos: se inscribieron 258 pacientes sanos de entre 3 meses y 15 años (6,77 ± 3,95 años; 73,6 % de hombres). Resultados: el valor medio de 25(OH)D fue de 26,60 ng/ml ± 8,02 ng/ml; el 20,9 % de la población mostró un nivel insuficiente. Se observaron diferencias estadísticamente significativas entre los niveles de vitamina D de las distintas edades (p = 0,002), grupos étnicos (p = 0,038) y fototipos (p = 0,000). Además, se observó una mayor prevalencia de la insuficiencia de vitamina D en los niños que nunca antes habían recibido suplementos de vitamina D (41,6 %) en comparación con los que habían tomado suplementos en el primer año de vida (16,7 %). Conclusiones: el presente estudio muestra una alta prevalencia del déficit de vitamina D en los niños sanos y el beneficio de una correcta profilaxis en edades tempranas con suplementos de vitamina D.

Vitamin D deficiency in primary health care users at risk in Spain.

INTRODUCTION: Background and objectives: despite long hours of sunlight in Spain, vitamin D deficiency has been rising of late. We aimed to describe vitamin D deficiency and insufficiency in at-risk patients in La Rioja, a region in northern Spain. Methods: a retrospective, cross-sectional study involving 21,490 patients (74.3 % women) aged 14-105 years, who were primary health care (PHC) users in La Rioja, with an available 25-hidroxyvitamin D (25(OH)D) test result corresponding to the first request from January 2013 to October 2015. Vitamin D deficiency, insufficiency, and sufficiency were defined as 25(OH)D levels < 12 ng/mL, 12-20 ng/mL, and ≥ 20 ng/mL, respectively. Hypovitaminosis D was defined considering 2 cut-off points for 25(OH)D: < 20 ng/mL and < 30 ng/mL. Results: mean 25(OH)D levels were 18.3 (SD, 11.6) ng/mL in the whole sample, being lower in men than in women (17.6 vs 18.5 ng/mL, p < 0.001). Significantly higher 25(OH)D levels were found in the groups with 55-59, 60-64, 65-69, and 70-74 years of age (range, 19.4-20.4 ng/mL), and lower levels were found in the groups with 80-85 years and older (16.7 and 14.5 ng/mL), as compared to other groups. Two thirds of the population were vitamin D-deficient (< 12 ng/mL, 30.9 %) or insufficient (12-20 ng/mL, 32.8 %), and only 32.8 % of patients were found to be vitamin D-sufficient (> 20 ng/ml). Hypovitaminosis D rate was higher (89.7 %) when the 25(OH)D cut-off point was set at < 30 ng/mL. A higher hypovitaminosis D rate (< 20 ng/mL) was found in men (67.1 %) vs women (62.6 %) (p < 0.001), and it was more prevalent in patients over 75 years (72.6 %). The prevalence of hypovitaminosis D followed a seasonal pattern ranging from 51.8 % to 76.5 %; the lowest 25(OH)D levels were found in winter, and the highest in summer, with levels above 20 ng/mL in all age groups except for patients over 75 years (17.7 ng/mL). Patients over 75 years exhibited high rates of deficiency or insufficiency across all seasons of the year. Conclusions: in La Rioja, Spain, hypovitaminosis D was highly prevalent among PHC users, and especially in older age groups and during the winter months.

INTRODUCCIÓN: Justificación y objetivos: a pesar de las largas horas de exposición solar en España, la deficiencia de vitamina D ha ido en aumento. Nuestro objetivo fue describir la deficiencia e insuficiencia de vitamina D en pacientes de riesgo en La Rioja, España. Métodos: estudio transversal retrospectivo en el que participaron 21.490 pacientes (74,3 % mujeres), usuarios de Atención Primaria (APS) en La Rioja, con resultado de prueba de 25-hidroxivitamina D (25(OH) D) disponible, correspondiente a las solicitudes efectuadas entre enero de 2013 y octubre de 2015. La deficiencia, insuficiencia y suficiencia de vitamina D se definieron como niveles de 25(OH)D < 12 ng/mL, = 12-20 ng/mL y ≥ 20 ng/mL, respectivamente. La hipovitaminosis D se definió considerando 2 puntos de corte de 25(OH)D: < 20 ng/mL y < 30 ng/mL. Resultados: los valores medios de 25(OH)D fueron de 18,3 (DE: 11,6) ng/mL en toda la muestra, siendo menores en los hombres que en las mujeres (17,6 vs. 18,5 ng/mL, p < 0,001). Se encontraron niveles de 25(OH)D significativamente más altos en los grupos de 55-59, 60-64, 65-69 y 70-74 años (rango, 19,4-20,4 ng/mL), y más bajos en los grupos de 80-85 años y mayores (16,7 y 14,5 ng/mL) en comparación con otros grupos. Dos tercios de la población presentaban deficiencia de vitamina D (< 12 ng/mL, 30,9 %) o insuficiencia (12-20 ng/mL, 32,8 %), y solo el 32,8 % de los pacientes presentaban niveles suficientes de vitamina D (> 20 ng/mL). La hipovitaminosis D fue mayor (89,7 %) cuando el punto de corte de 25(OH)D se estableció en < 30 ng/mL. Se encontró una mayor tasa de hipovitaminosis D (< 20 ng/mL) en los hombres (67,1 %) que en las mujeres (62,6 %) (p < 0,001), y dicha hipovitaminosis fue más prevalente en los pacientes mayores de 75 años (72,6 %). La prevalencia de la hipovitaminosis D siguió un patrón estacional que varió del 51,8 % al 76,5 %. Los niveles más bajos de 25(OH)D se encontraron en invierno y los más altos en verano, con niveles por encima de 20 ng/mL en todos los grupos de edad excepto en los pacientes mayores de 75 años (17,7 ng/mL). Los pacientes mayores de 75 años presentaron altas tasas de deficiencia o insuficiencia durante todas las estaciones del año. Conclusiones: en La Rioja, España, la hipovitaminosis D fue altamente prevalente entre los usuarios de APS y, especialmente, en los grupos de mayor edad y durante los meses de invierno.

Niveles de 25(OH)D durante la pandemia de COVID-19: impacto del confinamiento y la radiación ultravioleta / 25(OH)D levels during the COVID-19 pandemic: impact of lockdown and ultraviolet radiation

Resumen Antecedentes: Las políticas de confinamiento domiciliario durante la pandemia de COVID-19 limitaron la exposición solar y pudieron influir en los niveles de vitamina D. Objetivo: Evaluar los cambios en 25(OH)D durante la pandemia de COVID-19 y el impacto del aislamiento social, preventivo y obligatorio (ASPO) en la dosis recomendada de radiación UV modificada por las nubes para la síntesis de vitamina D (UVDVC). Material y métodos: Se realizó un estudio retrospectivo de 15 908 pacientes en quienes se determinó el nivel de 25(OH)D entre enero de 2019 y diciembre de 2021 en un laboratorio centralizado en Rosario, Argentina. Resultados: Se constataron niveles más bajos de 25(OH)D en menores de 40 años durante 2020, así como una variación durante el período pandémico, con menores valores en la primera ola. Se registraron menores niveles de 25(OH)D en el período posterior al ASPO en comparación con el período de ASPO (p < 0.00001), además de mayor frecuencia de hipovitaminosis D (48.6 % versus 36.1 %). No se observaron estas diferencias en la comparación de los mismos períodos de 2019. La UVDVC no varió entre 2019 y 2020. Conclusiones: Las restricciones por la pandemia de COVID-19 llevaron a mayor frecuencia de hipovitaminosis D y menor frecuencia de valores óptimos.

Abstract Background: Home confinement policies during the COVID-19 pandemic limited sun exposure and may have influenced on vitamin D levels. Objective: To assess changes in 25(OH)D during the COVID-19 pandemic and the impact of Mandatory Preventive Social Isolation (MPSI) on UV radiation recommended dose modified by clouds for the synthesis of vitamin D (UVDVC). Material and methods: A retrospective study was carried out on 15,908 patients in whom the level of 25(OH)D was determined between January 2019 and December 2021 in a centralized laboratory in Rosario, Argentina. Results: Lower levels of 25(OH)D were documented in people younger than 40 years during 2020, as well as a variation during the pandemic period, with lower values in the first wave. Lower levels of 25(OH)D were recorded in the post-MPSI period in comparison with the MPSI period (p < 0.00001), in addition to a higher frequency of hypovitaminosis D (48.6% vs. 36.1%). These differences were not observed in the comparison of the same periods of 2019. UVDVC did not vary between 2019 and 2020. Conclusions: The restrictions due to the COVID-19 pandemic led to a higher frequency of hypovitaminosis D and lower frequency of optimal values.

VITAMINA D EN LA PREVENCIÓN Y EVOLUCIÓN DE LA DIABETES MELLITUS / VITAMIN D IN THE PREVENTION AND EVOLUTION OF DIABETES MELLITUS

Introducción: El déficit de vitamina D y la diabetes son dos situaciones prevalentes en todas las edades, regiones geográficas y niveles socioeconómicos. La presencia de receptores para 1,25(OH)2D y la existencia de la enzima 1-α-hidroxilasa en la célula beta ­que permite la síntesis del metabolito activo­ sugieren que la vitamina D juega un papel importante en dichas células y que su deficiencia podría ser un factor capaz de acelerar el inicio y la evolución de la enfermedad. Objetivos: Se realizó una revisión del tema vitamina D y Diabetes. A su vez, se analizó el rol de la vitamina D en la insulinorresistencia y en la DM2, así como en la autoinmunidad y la DM1. También se indagó en el estado actual sobre los efectos de la suplementación con vitamina D en la prevención, el control glucémico y la evolución de las complicaciones asociadas a esta enfermedad. Materiales y Métodos: Se realizó una búsqueda bibliográfica utilizando los buscadores PubMed, MEDLINE, Cochrane, Research Gate. Los criterios de búsqueda fueron "vitamin D", "vitamin D and diabetes", "vitamin D and supplementation". Conclusiones: Existe suficiente evidencia acerca de que los niveles séricos de 25(OH)D deberían alcanzar valores entre 30 y 50 ng/ml para influir en las funciones metabólicas. Se enfatiza en la importancia de incluir el dosaje de 25(OH)D en el control clínico de rutina. Teniendo en cuenta la escasa distribución de la vitamina D en los alimentos naturales, el bajo consumo de los alimentos fuente en la población argentina y las recomendaciones actuales de limitar la exposición al sol por el cáncer de piel, emerge como necesario contar con alimentos fortificados de consumo masivo, además de la leche

Introduction: Vitamin D deficiency and diabetes are two prevalent situations in all ages, geographic regions and socioeconomic levels. The presence of receptors for 1,25(OH)2D and the existence of the enzyme 1-α-hydroxylase in the beta cell ­which allows the synthesis of the active metabolite­ suggest that vitamin D plays an important role in these cells and that vitamin deficiency could be a factor that can accelerate the onset and progression of the disease. Objectives: The subject vitamin D and Diabetes was review. The role of vitamin D in insulin resistance and DM2, as well as autoimmunity and DM1, were analyze. We also evaluated the effects of vitamin D supplementation on prevention, glycemic control and evolution of associated complications. Materials and methods: A bibliographic search was carried out using the search engines PubMed, MEDLINE, Cochrane, Research Gate. The search criteria were "vitamin D", "vitamin D and diabetes", "vitamin D and supplementation". Conclusions: There is sufficient evidence that blood levels of 25(OH)D should reach values between 30 and 50 ng/ml to influence metabolic functions. The importance of including 25(OH)D dosage in routine clinical control is emphasized. Taking into account the scarce distribution of vitamin D in natural foods, the low consumption of source foods in the Argentine population and the current recommendations to limit sun exposure due to skin cancer, it emerges as necessary to have fortified foods for mass consumption, in addition to milk

Risk of vitamin D deficit in asthmatic children hospitalized in the north area of Santiago / Riesgo de déficit de vitamina D en niños asmáticos hospitalizados en el área norte de Santiago

Introduction: in recent years asthma hospitalization rate in Chilean children has doubled. Numerous studies have shown an association between hypovitaminosis D and frequent, severe asthmatic exacerbations in children. Objective: to estimate the risk of vitamin D (vitD) deficiency and insufficiency in hospitalized asthmatic children compared with patients who are monitored on an outpatient basis and do not have records of hospitalization in one year. Material and methods: an observational, analytic, and case-control study carried out in one calendar year including asthmatic children between 5 and 15 years of age. This study registered: sociodemographic and clinical data, asthma control test, severity score of hospitalization and measurements of vitD blood levels. Associations between variables were analyzed using the t-test and chi-squared test. The risk for hypovitaminosis D and deficiency was calculated through logistic regression. The data was fed into the Stata 14 software. Results: a total of 117 patients, 9 ± 2.7 years old, were admitted, 64 % were male and 51 % presented with malnutrition by excess. Six out of ten children presented moderate asthma and 55 % had a poor control of their pathology; 73.5 % presented hypovitaminosis D (insufficiency and deficiency), hospitalized patients had 2.8 times more risk of presenting vitD deficiency, adjusted according to seasonality and age (95 %CI, 1.07-7.5, p < 0.05) without being associated with a higher severity score of hospitalization. Conclusion: Most of the asthmatic children in the sample presented with hypovitaminosis D, with a higher percentage of deficiency in hospitalized patients, which is not associated with greater severity of hospitalization. (AU)

Introducción: la tasa de hospitalización por asma se ha duplicado en los últimos años en Chile. Numerosos estudios demuestran una asociación entre la hipovitaminosis D y la presencia de exacerbaciones frecuentes y severas. Objetivo: comparar el riesgo de déficit e insuficiencia de vitamina D (vitD) en niños asmáticos que se hospitalizan en relación con los que se tratan ambulatoriamente. Material y métodos: estudio observacional, analítico, de casos y controles realizado durante 1 año calendario. Se incluyó a pacientes asmáticos de 5 a 15 años. Se registraron datos sociodemográficos, clínicos, nivel de control de asma, puntaje de severidad de hospitalización y se midió la concentración sanguínea de vitD. Se analizó la asociación entre las variables mediante la prueba de la t y la del chi cuadrado. Mediante regresión logística se calculó el riesgo de hipovitaminosis D y déficit de vitD en los sujetos. Los datos se analizaron con el software Stata 14. Resultados: se enrolaron 117 pacientes de 9 ± 2,7 años, 64 % de varones y 51 % con malnutrición por exceso. Seis de cada diez niños presentaban asma moderada y el 55 % tenían mal control de su enfermedad. El 73,5 % de los sujetos presentaban hipovitaminosis D (déficit o insuficiencia). Los hospitalizados tuvieron 2,8 veces más riesgo de presentar déficit de vitD (IC 95 %: 1,07-7,5), ajustado según estacionalidad y edad, sin asociarse a mayor puntaje de severidad de la hospitalización. Conclusión: la mayoría de los niños asmáticos de la muestra presentan hipovitaminosis D, siendo mayor el porcentaje de déficit en los hospitalizados, lo que no se asocia a mayor severidad de la hospitalización. (AU)

Variaciones y diferentes percepciones en la suplementación con vitamina D en la edad pediátrica en España / Variations and different perceptions in vitamin D supplementation in paediatric age in Spain

Introducción: el raquitismo es un problema de salud a nivel global. La deficiencia de vitamina D se ha convertido en una pandemia, su interés ha aumentado por la implicación de la misma en múltiples acciones extraesqueléticas. Material y métodos: se realizó una encuesta a través de correo electrónico entre pediatras españoles para estudiar su actitud en relación con la suplementación profiláctica de vitamina D. Resultados: un 83% de los pediatras tienen políticas de profilaxis de vitamina D en su área. Un 61,6% inicia la profilaxis en las dos primeras semanas y un 81,5% la mantiene el primer año. Un 57,2% realiza una búsqueda de deficiencia de vitamina D, sobre todo si trabajan en medio hospitalario. Conclusiones: las políticas de profilaxis con vitamina D son bastantes uniformes. Más de la mitad de los pediatras españoles realizan una búsqueda sistemática mediante analítica de deficiencia de vitamina D en sus pacientes con factores de riesgo durante la infancia y adolescencia (AU)

Introduction: rickets is a global health problem. Vitamin D deficiency has become a pandemic, its interest has increased due to its implication in multiple extraskeletal actions.Material and methods: a survey was conducted by e-mail among spanish paediatricians to study their attitude regarding prophylactic vitamin D supplementation.Results: 83% of pediatricians have vitamin D prophylaxis policies in their area. 61.6% start prophylaxis in the first two weeks, 81.5% maintain it the first year. 57.2% search for vitamin D deficiency, especially if they work in a hospital.Conclusions: vitamin D prophylaxis policies are uniform. More than a half of Spanish pediatricians conduct a systematic search for vitamin D deficiency in their patients with risk factors during childhood and adolescence (AU)

Níveis séricos de vitamina D e urinários de KIM-1 e MCP-1 em pacientes com anemia falciforme / Serum levels of vitamin D, and urinary levels of KIM-1 and MCP-1 in patients with sickle cell anemia

Objetivo: realizar dosagens de biomarcadores de função renal não convencionais em pacientes com anemia falciforme e associar com os níveis séricos de vitamina D. Métodos: trata-se de um estudo observacional, analítico de corte transversal. Participaram do estudo 51 pacientes adultos com anemia falciforme, e o grupo controle foi composto por 17 adultos saudáveis doadores de sangue. Os níveis séricos de 25- hidroxi-vitamina D foram determinados por imunoensaio quimioluminecente de micropartículas (CMIA), e a função renal foi avaliada pelas dosagens de molécula-1 de lesão renal (KIM-1) e proteína-1 quimiotática de monócitos (MCP-1). Os resultados foram expressos como mediana (intervalo interquartil). Os testes t-Student de amostras independentes, análise de variância de Welch e teste não paramétrico de Kruskal-Wallis foram realizados para comparar as diferenças entre os grupos. Resultados: os pacientes apresentaram níveis séricos de vitamina D superiores ao grupo controle, além de uma maior prevalência de suficiência de vitamina D. Os níveis urinários de KIM-1 e MCP-1 estavam aumentados nos pacientes em relação ao grupo controle. Não houve relação entre baixos níveis séricos de vitamina D e a probabilidade de desenvolvimento de doença renal. Conclusões: este estudo fornece dados importantes sobre a prevalência da deficiência de vitamina D em pacientes com anemia falciforme e demonstra não haver relação entre baixos níveis de vitamina D e desenvolvimento de doença renal.

Objective: to measure non-conventional renal function biomarkers in patients with sickle cell anemia and associate them with serum levels of vitamin D. Method: this is an observational, analytical, cross-sectional study. Fifty-one adult patients with sickle cell anemia participated in the study, and the control group consisted of 17 healthy adult blood donors. Serum levels of 25-hydroxyvitamin D were determined by chemiluminescent microparticle immunoassay (CMIA), and renal function was assessed by measuring urinary Kidney Injury Molecule-1 (KIM-1) and Monocyte Chemoattractant Protein-1 (MCP-1). Results were expressed as median (interquartile range). Student's t-test, Welch analysis of variance, and non-parametric Kruskal-Wallis test were performed to compare differences between groups. Results: patients had higher serum levels of vitamin D than the control group, besides a higher prevalence of vitamin D sufficiency. Urinary levels of KIM-1 and MCP-1 were increased in patients compared to the control group. There was no relationship between low serum vitamin D levels and the likelihood of developing kidney disease. Conclusions: this study provides important data on the prevalence of vitamin D deficiency in patients with sickle cell anemia and demonstrates that there is no relationship between low levels of vitamin D and the development of kidney disease.

Programa de resistência muscular para membros inferiores melhora sarcopenia urêmica / Muscular resistance program for lower limbs improves uremic sarcopenia

Insuficiência renal crônica (IRC) é caracterizada pela deterioração irreversível dos néfrons, que causa uma condição crônica com prejuízo do desempenho físico dos indivíduos, principalmente de membros inferiores (MMII), devido a sarcopenia urêmica e déficit de vitamina D. Objetivo: Avaliar a eficiência de um programa de resistência muscular para MMII de pacientes com IRC. Métodos: Cinco pacientes com IRC participaram do programa de reabilitação que ocorreu 30 minutos antes do início da hemodiálise (HD), duas vezes por semana, cada sessão teve duração de 20 minutos, totalizando 14 sessões, sendo a primeira e última, destinadas a avaliação. A intervenção consistiu de circuito funcional e exercícios resistidos, isotônicos de cadeia cinética aberta e fechada. Foi avaliado o teste de sentar e levantar em 30 segundos e teste de uma repetição máxima (1RM). Resultados: Após a aplicação, foi verificado que a força muscular pós (2,92 ± 1,10) foi estatisticamente maior que a pré (1,90 ± 1,29, p= 0,02), além de evidenciar que as variáveis da progressão da carga e força muscular pós, estão diretamente correlacionadas (r² 0,976, p= 0,005). O desempenho no teste de sentar e levantar em 30 segundos obteve diferença significativa pré (6,8 ± 2,28) e pós intervenção (10,4 ± 1,67, p= 0,004). Conclusão: O programa de resistência muscular de MMII foi eficaz, visto que aumentou o desempenho físico funcional com ganho de força e resistência muscular em pacientes em HD

Chronic renal failure (CRF) is characterized by the irreversible deterioration of the nephrons, which causes a chronic condition with impaired physical performance of individuals, mainly of the lower limbs (LL), due to uremic sarcopenia and vitamin D deficit. Objective: To evaluate the efficiency of a muscular resistance program for the lower limbs of patients with CRF. Methods: Five patients with CRF participated in the rehabilitation program that took place thirty minutes before the beginning of hemodialysis (HD), twice a week, each session lasted 20 minutes, totaling 14 sessions, the first and last ones were destinated for evaluation. The intervention consisted of functional circuit and resistance exercises, isotonic with open and closed kinetic chain. The 30-second sit-and-stand test and the one maximum repetition test (1MR) were evaluated. Results: After application, it was found that post muscle strength (2.92 ± 1.10) was statistically higher than pre (1.90 ± 1.29, p= 0.02), in addition to showing that the variables of load progression and post muscle strength are directly correlated (r² 0.976, p= 0.005). The performance in the 30-second sit and stand test showed a significant difference pre (6.8 ± 2.28) and post intervention (10.4 ± 1.67, p= 0.004). Conclusion: The lower limbs muscular resistance program was effective, as it increased functional physical performance with gains in muscle strength and endurance in hemodialysis patients

Prevalencia de niveles bajos de 25(OH)-vitamina D en universitarios costarricenses / Prevalence of low 25 OH-Vitamin D levels in Costa Rican university students

Resumen Objetivo: Describir la prevalencia de hipovitaminosis D3 y sus características clínicas y bioquímicas en una población de universitarios costarricenses. Métodos: Investigación transversal y descriptiva en un total de 118 individuos sanos, de ambos sexos, con edades entre los 18-43 años. Se preguntó sobre historia familiar de enfermedades crónicas, nivel de exposición al sol, uso de protectores solares, presión arterial. En el laboratorio, se analizaron en suero: glucosa, calcio, fosfato, hormona paratiroidea, insulina, 25 OH-Vitamina D e inmunoglobulina E. Se calcularon el índice de masa corporal y el modelo matemático de evaluación para la homeostasis de la resistencia a la insulina. Resultados: La prevalencia de hipovitaminosis D3 (<30 ng/mL) en este estudio fue de 25% sin diferencia significativa por sexo. La concentración promedio de 25 OH-vitamina D fue 36,2 ng/mL, con valores que van desde 14,5 a 59,5 ng/mL. Un total de 26 estudiantes presentaba insuficiencia de 25 OH-vitamina D (21-29 ng/mL) y solamente 4 fueron clasificados con una deficiencia grave (<20 ng/mL). No se encontraron casos de hipervitaminosis D3 (>100 ng/mL) en la muestra de estudio. Al comparar aquellos sujetos con deficiencia de 25 OH-Vitamina D3 contra los que presentaron niveles séricos normales de esta vitamina, se observaron diferencias significativas solamente en dos parámetros bioquímicos: insulina (10,9 ± 7,4 µUI/ mL vs 8,3 ± 4,1 µUI/mL; p=0,017) y el índice HOMA IR (2,48 ± 1,86 vs 1,85 ± 0,3; p=0,002). Cerca de la mitad de los estudiantes relataron antecedentes familiares de diabetes mellitus (49,2%) e hipertensión arterial (52,9%). El 29% de los participantes tenía sobrepeso y obesidad. Conclusiones: El 25% de los sujetos estudiados presentó deficiencia de 25 OH-Vitamina D. Estos sujetos, a su vez, presentaron una mayor prevalencia de hiperinsulinemia y resistencia a la insulina en comparación con personas con concentraciones normales de esta vitamina. También existe una alta prevalencia de factores de riesgo entre los familiares de la población joven, los cuales podrían aumentar el riesgo de estos estudiantes de padecer diabetes mellitus o enfermedades cardiovasculares en un futuro cercano.

Abstract Objective: To determine the prevalence of hypovitaminosis D3 in a population of Costa Rican University students and describe its clinical and biochemical characteristics. Methods: Cross-sectional and descriptive research with a total of 118 healthy individuals of both genders aged between 18-43 years. Questions were asked about family history of chronic diseases, level of sun exposure, use of sunscreens, blood pressure. In the laboratory, glucose, calcium, phosphate, parathyroid hormone, insulin, 25 OH-Vitamin D and immunoglobulin E were analyzed in serum. Body Mass Index and the mathematical assessment model for the homeostasis of insulin resistance were calculated. Results: The prevalence of hypovitaminosis D3 (<30 ng/mL) in this study was 25% with no significant difference by sex. The average concentration of 25 OH-Vitamin D was 36.2 ng/mL, with values ranging from 14.5 to 59.5 ng/mL. A total of 26 students had 25 OH- Vitamin D insufficiency (21-29 ng/mL) and only 4 were classified as severely deficient (<20 ng/mL). No cases of hypervitaminosis D3 (> 100 ng/mL) were found in the study sample. When comparing those subjects with 25 OH-Vitamin D3 deficiency against those with normal serum levels of this vitamin, significant differences were observed only in two biochemical parameters: insulin (10.9 ± 7.4 µIU/mL vs 8.3 ± 4.1 µUI/mL; p=0.017) and the HOMA IR index (2.48 ± 1.86 vs 1.85 ± 0.3; p=0.002). Nearly half of the students reported a family history of Diabetes Mellitus (49.2%) and arterial hypertension (52.9%). Near 29% of the participants were overweight and obese. Conclusions: Around 25% of the subjects studied presented 25 OH-Vitamin D deficiency. These subjects, in turn, presented a higher prevalence of hyperinsulinemia and insulin resistance compared with people with normal concentrations of this vitamin. There is also a high prevalence of risk factors among the relatives of the young population that could increase the risk of these students of suffering from Diabetes Mellitus or cardiovascular diseases in the future.

O que as revisões sistemáticas Cochrane mostram sobre a vitamina D? / What do Cochrane systematic reviews show about vitamin D?

Contextualização: A vitamina D tem sido utilizada na prática clínica e amplamente divulgada na mídia como opção preventiva ou terapêutica em muitas doenças esqueléticas e não esqueléticas, mas sua efetividade, em muitos casos, é ainda incerta. Objetivos: Sumarizar as evidências de revisões sistemáticas da Cochrane, referentes à efetividade da vitamina D para tratamento e prevenção de doenças. Métodos: Trata-se de overview de revisões sistemáticas Cochrane. Procedeu-se à busca na Cochrane Library (2023), sendo utilizado o descritor MeSH "VITAMIN D". Todas as revisões sistemáticas de ensaios clínicos foram incluídas. O desfecho primário de análise foi a melhora clínica, a redução dos sintomas ou a prevenção da doença. Resultados: 22 estudos foram incluídos, totalizando 284.404 participantes. Há evidência de baixa qualidade relativa a benefícios da suplementação da vitamina D na gestação para mãe e recém-nascido, não sendo encontrados, até o momento, benefícios para outras condições avaliadas. Discussão: Nenhuma intervenção mostrou efetividade com evidência de boa qualidade. Embora haja descrição de benefícios na redução do risco de pré-eclâmpsia, diabetes gestacional, baixo peso do bebê ao nascimento, redução no risco de hemorragia grave pós-parto e redução de fraturas em idosos (quando associada à suplementação de cálcio), esses achados têm evidência limitada e carecem de melhor análise no futuro próximo, a partir de novos ensaios clínicos. Conclusão: Atualmente, não há suporte com bom nível de evidência para a maioria das intervenções com suplementação de vitamina D, sendo recomendada a realização de novos ensaios clínicos para melhor robustez dos achados desses estudos.