RESUMO
BACKGROUND: Several studies have suggested an association between vitamin deficiency and the development of tuberculosis; however, the precise impact remains unclear. This study aimed to elucidate the relationship between distinct vitamin statuses and the occurrence of tuberculosis. MATERIALS AND METHODS: Retrieval was conducted using several databases without language restrictions to capture the eligible studies on tuberculosis and vitamin status. Pooled odds ratios (ORs), relative risks (RRs), and hazard ratios (HRs) were used with 95% confidence intervals (CIs) to clarify the relationship between the different vitamin statuses (A, B, D, and E) and the occurrence of tuberculosis. Subgroup analysis, sensitivity analysis, meta-regression analysis, and Galbraith plot were performed to determine sources of heterogeneity. Potential publication biases were detected using Begg's test, Egger's test, and the trim-and-fill test. RESULTS: We identified 10,266 original records from our database searches, and 69 eligible studies were considered in this study. The random-effect model showed that people with tuberculosis may exhibit vitamin A deficiency (OR = 10.66, 95%CI: 2.61-43.63, p = .001), while limited cohort studies showed that vitamin A supplementation may reduce tuberculosis occurrence. Additionally, vitamin D deficiency was identified as a risk factor for tuberculosis development (RR = 1.69, 95%CI: 1.06-2.67, p = .026), and people with tuberculosis generally had lower vitamin D levels (OR = 2.19, 95%CI: 1.76-2.73, p < .001) compared to other groups. No publication bias was detected. CONCLUSIONS: This meta-analysis indicated that people with tuberculosis exhibited low levels of vitamins A and D, while vitamin D deficiency was identified as a risk factor for tuberculosis. More randomized controlled interventions at the community levels should be recommended to determine the association between specific vitamin supplementation and tuberculosis onset.
Assuntos
Tuberculose , Deficiência de Vitamina A , Deficiência de Vitamina D , Humanos , Tuberculose/epidemiologia , Deficiência de Vitamina D/epidemiologia , Deficiência de Vitamina D/complicações , Deficiência de Vitamina A/epidemiologia , Deficiência de Vitamina A/complicações , Deficiência de Vitamina A/sangue , Fatores de Risco , Vitamina A/sangue , Suplementos Nutricionais , Vitaminas/sangue , Vitamina D/sangue , Deficiência de Vitamina E/epidemiologia , Deficiência de Vitamina E/complicações , Deficiência de Vitamina E/sangue , Feminino , Masculino , Razão de Chances , Adulto , Vitamina E/sangueRESUMO
BACKGROUND: This study evaluates the association between vitamin A levels, AIP (the atherogenic index of plasma), and subclinical hypothyroidism. METHODS: A cross-sectional analysis was conducted involving a representative sample of 3530 Chinese adults. Linear and logistic regression models were utilized to evaluate the associations between AIP and subclinical hypothyroidism, stratified by vitamin A levels. These analyses were further differentiated by sex and age groups to identify any demographic-specific associations. RESULTS: In the vitamin A-sufficient group, an increase in AIP was associated with elevated total triiodothyronine (TT3) levels (ß = 0.26, 95%CI: 0.09, 0.41, p = 0.003). Conversely, in the group with severe vitamin A deficiency, higher AIP levels were linked to increased free triiodothyronine (fT3) and TT3 levels and decreased free thyroxine (fT4) levels (ß = 0.12, 0.03, and -0.29, respectively). Additionally, severe vitamin A deficiency increased the risk associated with AIP and subclinical hypothyroidism (OR = 1.66, 95%CI: 1.07, 2.58, p = 0.025). This risk was notably more pronounced in women and older adults, with odds ratios of 2.44 (95%CI: 1.55, 3.86, p < 0.001) and 2.14 (95%CI: 1.36, 3.38, p = 0.001), respectively. CONCLUSIONS: Vitamin A deficiency may increase the risk of the association between AIP and subclinical hypothyroidism, particularly among women and the elderly.
Assuntos
Hipotireoidismo , Deficiência de Vitamina A , Vitamina A , Humanos , Hipotireoidismo/sangue , Hipotireoidismo/epidemiologia , Feminino , Masculino , Estudos Transversais , China/epidemiologia , Pessoa de Meia-Idade , Adulto , Deficiência de Vitamina A/sangue , Deficiência de Vitamina A/epidemiologia , Vitamina A/sangue , Aterosclerose/sangue , Aterosclerose/epidemiologia , Aterosclerose/etiologia , Idoso , Tri-Iodotironina/sangue , Fatores de Risco , Tiroxina/sangue , Doenças AssintomáticasRESUMO
Introduction: Maternal nutritional and vitamin status during pregnancy may have long-term effects on offspring health and disease. The aim of this study was to examine the associations between maternal vitamin A and D status in pregnancy and offspring bone mineral content (BMC) at nine years of age. Methods: This is a post-hoc study of a randomized control trial including 855 pregnant women from two Norwegian cities; Trondheim and Stavanger. The women were randomized into an exercise intervention or standard antenatal care. Mother and child pairs for the present study were recruited from those still living in Trondheim after 8-10 years. Serum vitamin A (retinol) and vitamin D (25(OH)D) were measured in the 2nd and 3rd trimesters of pregnancy, and active vitamin D (1,25(OH)2D) in serum was measured in a subgroup. Spine BMC and trabecular bone score were measured in the children at nine years of age. Associations were analyzed with linear regression models. Results: A total of 119 mother and child pairs were included in the analyses. Vitamin A insufficiency (retinol< 1.05 µmol/L) and vitamin D deficiency (25(OH)D< 50 mmol/L) increased from ~7% to ~43% and from ~28% to ~33%, respectively, from the 2nd to the 3rd trimester. An increase in serum 1,25(OH)2D from the 2nd to the 3rd trimester was observed in the subgroup. There was a negative association between serum retinol in the 2nd trimester and spine BMC in the boys, but not in the girls, when adjusted for maternal and child confounders. No other associations between maternal serum vitamin A or D and BMC in the children were found. Conclusion: We observed a high prevalence of vitamin A insufficiency and vitamin D deficiency during pregnancy. A negative association between mid-pregnancy vitamin A status and spine BMC was observed in boys, but not girls, while no associations were found between maternal vitamin D status and child BMC. The implications of optimal vitamin A and D status in pregnancy for offspring bone health, remains a subject for further investigations.
Assuntos
Densidade Óssea , Segundo Trimestre da Gravidez , Terceiro Trimestre da Gravidez , Vitamina A , Vitamina D , Humanos , Feminino , Gravidez , Vitamina A/sangue , Vitamina D/sangue , Terceiro Trimestre da Gravidez/sangue , Masculino , Criança , Adulto , Segundo Trimestre da Gravidez/sangue , Deficiência de Vitamina D/epidemiologia , Deficiência de Vitamina D/sangue , Deficiência de Vitamina A/sangue , Deficiência de Vitamina A/epidemiologia , Noruega/epidemiologia , Fenômenos Fisiológicos da Nutrição Materna , Efeitos Tardios da Exposição Pré-Natal/sangue , Efeitos Tardios da Exposição Pré-Natal/epidemiologiaRESUMO
Excessive vitamin A (VA) negatively impacts bone. Interactions between VA and vitamin D (VD) in bone health are not well-understood. This study used a traditional two-by-two factorial design. Pigs were weaned and randomized to four treatments (n = 13/group): -A-D, -A+D, +A-D, and +A+D for 3 and 5 wk. Serum, liver, kidney, adrenal glands, spleen, and lung were analyzed by ultra-performance LC. Growth was evaluated by weight measured weekly and BMD by DXA. Weights were higher in -A+D (18.1 ± 1.0 kg) and +A+D (18.2 ± 2.3 kg) at 5 wk than in -A-D (15.5 ± 2.1 kg) and +A-D (15.8 ± 1.5 kg). Serum retinol concentrations were 0.25 ± 0.023, 0.22 ± 0.10, 0.77 ± 0.12, and 0.84 ± 0.28 µmol/L; and liver VA concentrations were 0.016 ± 0.015, 0.0065 ± 0.0035, 2.97 ± 0.43, 3.05 ± 0.68 µmol/g in -A-D, -A+D, +A-D, and +A+D, respectively. Serum 25(OH)D3 concentrations were 1.5 ± 1.11, 1.8 ± 0.43, 27.7 ± 8.91, and 23.9 ± 6.67 ng/mL in -A-D, +A-D, -A+D, +A+D, respectively, indicating a deficiency in -D and adequacy in +D. BMD was highest in +D (p < 0.001). VA and the interaction had no effect on BMD. Dietary VD influenced weight gain, BMD, and health despite VA status.
Assuntos
Densidade Óssea , Deficiência de Vitamina A , Vitamina A , Vitamina D , Animais , Densidade Óssea/efeitos dos fármacos , Vitamina D/sangue , Suínos , Vitamina A/sangue , Feminino , Masculino , Modelos Animais de Doenças , Fígado/metabolismo , Fígado/efeitos dos fármacos , Suplementos NutricionaisRESUMO
BACKGROUND: This study aimed to investigate the impact of Vitamin A (VA) on intestinal glucose metabolic phenotypes. METHODS: Male C57BL/6 mice were randomized assigned to a VA-normal diet (VAN) or a VA-deficient diet (VAD) for 12 weeks. After12 weeks, the VAD mice were given 30 IU/g/d retinol for 10 days and VAN diet (VADN) for 10 weeks. By using glucose tolerance tests, immunofluorescence staining, quantitative polymerase chain reaction, siRNA transduction, and enzyme-linked immunosorbent assay, the glucose metabolic phenotypes as well as secretory function and intracellular hormone changes of STC-1 were assessed. RESULTS: VAD mice showed a decrease of glucose-stimulated insulin secretion and a loss of intestinal glucagon-like peptide-1 (GLP-1) expression. Through reintroducing dietary VA to VAD mice, the intestinal VA levels, GLP-1 expression and normal glucose can be restored. The incubation with retinol increased VA signaling factors expression within STC-1 cells, especially retinoic acid receptor ß (RARß). The activation of RARß restored intracellular incretin hormone synthesis and secretory function. CONCLUSIONS: VA deficiency leads to an imbalance of intestinal glucose metabolic phenotypes through a mechanism involving RARß signaling pathway, suggesting a new method to achieve the treatment for VAD induced glucose metabolism impairment.
Assuntos
Peptídeo 1 Semelhante ao Glucagon , Incretinas , Camundongos Endogâmicos C57BL , Receptores do Ácido Retinoico , Vitamina A , Animais , Masculino , Vitamina A/metabolismo , Camundongos , Receptores do Ácido Retinoico/metabolismo , Receptores do Ácido Retinoico/genética , Incretinas/metabolismo , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Deficiência de Vitamina A/metabolismo , Mucosa Intestinal/metabolismo , Mucosa Intestinal/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Secreção de Insulina/efeitos dos fármacos , Secreção de Insulina/fisiologiaRESUMO
BACKGROUND: Micronutrient deficiencies associated with malnutrition in patients with inflammatory bowel disease (IBD) can lead to complications including anemia, coagulopathy, poor wound healing, and colorectal cancer. This study aimed to investigate micronutrient deficiencies (copper, vitamins A, B 9 , E, and K) in IBD patients and highlight associated symptoms to aid in the recognition of micronutrient deficiencies. METHODS: A retrospective electronic chart review was performed on adults diagnosed with Crohn's disease or ulcerative colitis hospitalized at a tertiary care center for IBD flare between January 2013 and June 2017. Patients with serum or whole blood micronutrient levels were included. Pregnant and incarcerated patients were excluded. RESULTS: A total of 611 IBD patients (440 Crohn's disease, 171 ulcerative colitis) met the inclusion criteria. Micronutrients were assessed in a subset of IBD patients (copper: 12.3%, A: 10.1%, B 9 â :â 95.9%, E: 10.3%, and K: 4.6%). Overall, 10.1% of patients had micronutrient deficiencies. The proportion of patients with copper, A, B 9 , E, and K deficiencies were 25.4, 53.3, 1.9, 23.7, and 29.4% for Crohn's disease and 50, 52.9, 1.2, 43.8, and 18.2% for ulcerative colitis, respectively. The most common symptoms or historical features associated with micronutrient deficiency were anemia (copper, B 9 ), muscle weakness (copper, E) thrombocytopenia, fatigue (copper, B 9 ), diarrhea (B 9 ), dry skin, hyperkeratosis, pruritus, significant weight loss, elevated C-reactive protein (A), bleeding, and osteoporosis (K). CONCLUSION: Micronutrient deficiencies are common in IBD patients, yet they are not routinely assessed. Copper, vitamins A, E, and K deficiencies are particularly underrecognized. Associated historical features should raise suspicion and prompt assessment and treatment.
Assuntos
Colite Ulcerativa , Cobre , Doença de Crohn , Micronutrientes , Humanos , Feminino , Masculino , Estudos Retrospectivos , Adulto , Micronutrientes/deficiência , Micronutrientes/sangue , Pessoa de Meia-Idade , Doença de Crohn/epidemiologia , Doença de Crohn/sangue , Doença de Crohn/complicações , Doença de Crohn/diagnóstico , Colite Ulcerativa/epidemiologia , Colite Ulcerativa/diagnóstico , Colite Ulcerativa/complicações , Colite Ulcerativa/sangue , Cobre/deficiência , Cobre/sangue , Incidência , Deficiência de Vitamina A/epidemiologia , Deficiência de Vitamina A/complicações , Deficiência de Vitamina A/sangue , Deficiência de Vitamina A/diagnóstico , Deficiência de Vitamina E/epidemiologia , Deficiência de Vitamina E/sangue , Deficiência de Vitamina E/complicações , Deficiência de Vitamina E/diagnóstico , Desnutrição/epidemiologia , Desnutrição/diagnóstico , Desnutrição/sangue , Vitamina E/sangue , Vitamina A/sangue , Idoso , Estado Nutricional , Adulto JovemRESUMO
Vitamin A (VA) has many functions in the body, some of which are key for the development and functioning of the nervous system, while some others might indirectly influence neural function. Both hypovitaminosis and hypervitaminosis A can lead to clinical manifestations of concern for individuals and for general global health. Scientific evidence on the link between VA and autism spectrum disorder (ASD) is growing, with some clinical studies and accumulating results obtained from basic research using cellular and animal models. Remarkably, it has been shown that VA deficiency can exacerbate autistic symptomatology. In turn, VA supplementation has been shown to be able to improve autistic symptomatology in selected groups of individuals with ASD. However, it is important to recognize that ASD is a highly heterogeneous condition. Therefore, it is important to clarify how and when VA supplementation can be of benefit for affected individuals. Here we delve into the relationship between VA and ASD, discussing clinical observations and mechanistic insights obtained from research on selected autistic syndromes and laboratory models to advance in defining how the VA signaling pathway can be exploited for treatment of ASD.
Assuntos
Transtorno do Espectro Autista , Vitamina A , Transtorno do Espectro Autista/metabolismo , Humanos , Vitamina A/metabolismo , Animais , Deficiência de Vitamina A/complicações , Deficiência de Vitamina A/metabolismo , Suplementos NutricionaisRESUMO
BACKGROUND: Inadequate vitamin A (VA) intake is common among lactating women in many communities worldwide, but high-dose VA supplementation for postpartum women is not recommended by the World Health Organization as an effective intervention. OBJECTIVES: To simulate the impact of VA intake via diet and daily VA supplements on VA total body stores (TBS) and balance in theoretical lactating women with low/moderate TBS. METHODS: We studied 6 theoretical subjects with assigned values for TBS from 219-624 µmol. Using Simulation, Analysis, and Modeling software and a previously published compartmental model for whole-body VA metabolism, we simulated TBS over 6 mo of established lactation for each subject under 4 conditions: 1) prelactation VA intake was increased to maintain VA balance (LSS); 2) prelactation VA intake was maintained (NLSS); 3) VA intake was the same as 2) but a daily VA supplement (2.8 µmol/d) was added (NLSS+S); and 4) VA intake was as 1) and the daily VA supplement was included (LSS+S). RESULTS: To compensate for the loss of VA via milk while VA balance was maintained (LSS) over 6 mo of lactation, VA intake had to increase by 0.8-1.87 µmol/d (n = 6) compared with NLSS. Over 6 mo of NLSS treatment, VA balance was negative (geometric mean, -0.77 µmol/d) compared with LSS, whereas balance was positive under NLSS+S and LSS+S conditions (0.75 and 1.5 µmol/d, respectively). For LSS, the proportion of total VA disposal was 37% via breastmilk, 32% from VA stores, and 32% from nonstorage tissues. CONCLUSIONS: Adding a daily VA supplement (2.8 µmol/d) to the diet of lactating women with suboptimal VA intake may effectively counterbalance the negative VA balance resulting from the output of VA via breastmilk and thus benefit both mother and infant by maintaining or increasing VA stores and breastmilk VA concentration.
Assuntos
Suplementos Nutricionais , Lactação , Vitamina A , Humanos , Feminino , Vitamina A/administração & dosagem , Modelos Biológicos , Adulto , Leite Humano/química , Deficiência de Vitamina ARESUMO
BACKGROUND: A Bartholin's gland abscess is one of the most common infections in women of reproductive age. Although Bartholin's gland abscesses have been reported in prepubertal children, they are rarer in prepubertal children than in adults. Herein, we report a case of bilateral Bartholin's gland abscesses in a 4-year-old girl with vitamin A deficiency. CASE PRESENTATION: A 4-year-old girl diagnosed with autism spectrum disorder was admitted to the hospital for close examination and treatment because of persistent fever and malaise. The child was a marked fussy eater and was diagnosed with corneal ulceration and night blindness secondary to vitamin A deficiency. Both of the patient's labia were swollen, and a diagnosis of a bilateral Bartholin's gland abscess was made using computed tomography. Incisional drainage was performed under general anesthesia. The patient's postoperative course was uneventful, and she was discharged from the hospital on day 8 after the surgery. During hospitalization, attempts were made to correct the vitamin deficiency by adding nutritional supplements to the diet. Three months after the surgery, no recurrence of abscesses was noted. CONCLUSIONS: Decreased immunocompetence and mucosal barrier function due to vitamin A deficiency is thought to be the underlying cause of Bartholin's gland abscesses. Although prepubertal Bartholin's gland abscesses have been reported, they are rare. To the best of our knowledge, no reports of bilateral Bartholin's gland abscesses potentially caused by vitamin A deficiency have been reported. When prepubertal girls present with Bartholin's gland abscesses, the presence of immunodeficiency due to vitamin or trace element deficiency should also be considered.
Assuntos
Abscesso , Glândulas Vestibulares Maiores , Deficiência de Vitamina A , Humanos , Feminino , Pré-Escolar , Abscesso/etiologia , Glândulas Vestibulares Maiores/patologia , Deficiência de Vitamina A/complicações , Tomografia Computadorizada por Raios X , Doenças da Vulva/microbiologia , Doenças da Vulva/cirurgia , Doenças da Vulva/patologia , Doenças da Vulva/etiologiaRESUMO
Porcine epidemic diarrhea virus (PEDV) causes a highly contagious enteric disease with major economic losses to swine production worldwide. Due to the immaturity of the neonatal piglet immune system and given the high virulence of PEDV, improving passive lactogenic immunity is the best approach to protect suckling piglets against the lethal infection. We tested whether oral vitamin A (VA) supplementation and PEDV exposure of gestating and lactating VA-deficient (VAD) sows would enhance their primary immune responses and boost passive lactogenic protection against the PEDV challenge of their piglets. We demonstrated that PEDV inoculation of pregnant VAD sows in the third trimester provided higher levels of lactogenic protection of piglets as demonstrated by >87% survival rates of their litters compared with <10% in mock litters and that VA supplementation to VAD sows further improved the piglets' survival rates to >98%. We observed significantly elevated PEDV IgA and IgG antibody (Ab) titers and Ab-secreting cells (ASCs) in VA-sufficient (VAS)+PEDV and VAD+VA+PEDV sows, with the latter maintaining higher Ab titers in blood prior to parturition and in blood and milk throughout lactation. The litters of VAD+VA+PEDV sows also had the highest serum PEDV-neutralizing Ab titers at piglet post-challenge days (PCD) 0 and 7, coinciding with higher PEDV IgA ASCs and Ab titers in the blood and milk of their sows, suggesting an immunomodulatory role of VA in sows. Thus, sows that delivered sufficient lactogenic immunity to their piglets provided the highest passive protection against the PEDV challenge. Maternal immunization during pregnancy (± VA) and VA sufficiency enhanced the sow primary immune responses, expression of gut-mammary gland trafficking molecules, and passive protection of their offspring. Our findings are relevant to understanding the role of VA in the Ab responses to oral attenuated vaccines that are critical for successful maternal vaccination programs against enteric infections in infants and young animals.
Assuntos
Imunidade Adaptativa , Anticorpos Antivirais , Infecções por Coronavirus , Imunidade Materno-Adquirida , Vírus da Diarreia Epidêmica Suína , Doenças dos Suínos , Vitamina A , Animais , Vírus da Diarreia Epidêmica Suína/imunologia , Feminino , Suínos , Gravidez , Vitamina A/administração & dosagem , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/veterinária , Infecções por Coronavirus/virologia , Anticorpos Antivirais/sangue , Doenças dos Suínos/imunologia , Doenças dos Suínos/prevenção & controle , Doenças dos Suínos/virologia , Animais Recém-Nascidos , Lactação/imunologia , Suplementos Nutricionais , Deficiência de Vitamina A/imunologia , ImunizaçãoRESUMO
BACKGROUND: According to global prevalence analysis studies, acute upper respiratory tract infections (URTIs) are the most common acute infectious disease in children, especially in preschool children. Acute URTIs lead to an economic burden on families and society. Vitamin A refers to the fat-soluble compound all-trans-retinol and also represents retinol and its active metabolites. Vitamin A interacts with both the innate immune system and the adaptive immune system and improves the host's defences against infections. Correlation studies show that serum retinol deficiency was associated with a higher risk of respiratory tract infections. Therefore, vitamin A supplementation may be important in preventing acute URTIs. OBJECTIVES: To assess the effectiveness and safety of vitamin A supplements for preventing acute upper respiratory tract infections in children up to seven years of age. SEARCH METHODS: We searched CENTRAL, MEDLINE, Embase, the Chinese Biomedical Literature Database, and two trial registration platforms to 8 June 2023. We also checked the reference lists of all primary studies and reviewed relevant systematic reviews and trials for additional references. We imposed no language or publication restrictions. SELECTION CRITERIA: We included randomised controlled trials (RCTs), which evaluated the role of vitamin A supplementation in the prevention of acute URTIs in children up to seven years of age. DATA COLLECTION AND ANALYSIS: We used the standard methodological procedures expected by Cochrane. MAIN RESULTS: We included six studies (27,351 participants). Four studies were RCTs and two were cluster-RCTs. The included studies were all conducted in lower-middle-income countries (two in India, two in South Africa, one in Ecuador, and one in Haiti). Three studies included healthy children who had no vitamin A deficiency, one study included children born to HIV-infected women, one study included low-birthweight neonates, and one study included children in areas with a high local prevalence of malnutrition and xerophthalmia. In two studies, vitamin E was a co-treatment administered in addition to vitamin A. We judged the included studies to be at either a high or unclear risk of bias for random sequence generation, incomplete outcome data, and blinding. Primary outcomes Six studies reported the incidence of acute URTIs during the study period. Five studies reported the number of acute URTIs over a period of time, but there was population heterogeneity and the results were presented in different forms, therefore only three studies were meta-analysed. We are uncertain of the effect of vitamin A supplementation on the number of acute URTIs over two weeks (risk ratio (RR) 1.00, 95% confidence interval (CI) 0.92 to 1.09; I2 = 44%; 3 studies, 22,668 participants; low-certainty evidence). Two studies reported the proportion of participants with an acute URTI. We are uncertain of the effect of vitamin A supplementation on the proportion of participants with an acute URTI (2 studies, 15,535 participants; low-certainty evidence). Only one study (116 participants) reported adverse events. No infant in either the placebo or vitamin A group was found to have feeding difficulties (failure to feed or vomiting), a bulging fontanelle, or neurological signs before or after vitamin A administration (very low-certainty evidence). Secondary outcomes Two studies (296 participants) reported the severity of subjective symptoms, presented by the mean duration of acute URTI. Vitamin A may have little to no effect on the mean duration of acute URTI (very low-certainty evidence). AUTHORS' CONCLUSIONS: The evidence for the use of vitamin A supplementation to prevent acute URTI is uncertain, because population, dose and duration of interventions, and outcomes vary between studies. From generally very low- to low-certainty evidence, we found that there may be no benefit in the use of vitamin A supplementation to prevent acute URTI in children up to seven years of age. More RCTs are needed to strengthen the current evidence. Future research should report over longer time frames using validated tools and consistent reporting, and ensure adequate power calculations, to allow for easier synthesis of data. Finally, it is important to assess vitamin A supplementation for preschool children with vitamin A deficiency.
Assuntos
Suplementos Nutricionais , Ensaios Clínicos Controlados Aleatórios como Assunto , Infecções Respiratórias , Vitamina A , Vitaminas , Humanos , Vitamina A/administração & dosagem , Infecções Respiratórias/prevenção & controle , Pré-Escolar , Lactente , Doença Aguda , Criança , Vitaminas/administração & dosagem , Deficiência de Vitamina A/prevenção & controle , Administração Oral , ViésRESUMO
BACKGROUND: Vitamin A (VA) deficiency and excess negatively affect development, growth, and bone health. The World Health Organization's standard of care for xerophthalmia due to VA deficiency, is 3 high-dose VA supplements of 50,000-200,000 IU, based on age, which may cause hypervitaminosis A in some individuals. OBJECTIVES: This study measured VA status following 3 VA doses in 2 piglet studies. METHODS: In Study 1, 5 groups of piglets (n = 10/group) were weaned 10 d postbirth to VA-free feed and orally administered 0; 25,000; 50,000; 100,000; or 200,000 IU VA ester on days 0, 1, and 7. On days 14 and 15, the piglets underwent the modified relative dose-response (MRDR) test for VA deficiency, and were killed. Tissues were collected for high-pressure liquid chromatography analysis. Study 2 used the same design in 3 groups (n = 13/group) weaned at 16 d and administered 0; 25,000; and 200,000 IU doses. RESULTS: In Study 1 (final weight: 3.6 ± 0.7 kg), liver VA concentration was hypervitaminotic in 40%, 90%, and 100% of 50,000; 100,000; and 200,000 IU groups, respectively. The 25,000 IU group was 100% adequate, and the placebo group was 40% deficient. In Study 2 (final weight: 8.7 ± 0.8 kg), where 200,000 IU could be prescribed to infants with a similar body weight, 31% of the piglets were hypervitaminotic, the 25,000 IU group was 100% VA adequate, and the placebo group was 100% deficient. The MRDR test measured deficiency in 50% and 70% of the placebo group in each study but had 3 false positives among hypervitaminotic piglets in Study 1. CONCLUSIONS: Repeated high-dose VA may cause hypervitaminosis, indicating dose sizes may need reduction. The MRDR resulted in false positives in a hypervitaminotic state during malnutrition and should be paired with serum retinyl ester evaluation to enhance VA status assessment in populations with overlapping interventions.
Assuntos
Suplementos Nutricionais , Hipervitaminose A , Vitamina A , Xeroftalmia , Animais , Vitamina A/administração & dosagem , Suínos , Xeroftalmia/tratamento farmacológico , Relação Dose-Resposta a Droga , Doenças dos Suínos/tratamento farmacológico , Deficiência de Vitamina A/tratamento farmacológico , Deficiência de Vitamina A/veterinária , Feminino , Masculino , Fígado/metabolismo , Fígado/efeitos dos fármacosRESUMO
The first evidence of the existence of vitamin A was the observation 1881 that a substance present in small amounts in milk was necessary for normal development and life. It was not until more than 100 years later that it was understood that vitamin A acts as a hormone through nuclear receptors. Unlike classical hormones, vitamin A cannot be synthesized by the body but needs to be supplied by the food as retinyl esters in animal products and ß-carotene in vegetables and fruits. Globally, vitamin A deficiency is a huge health problem, but in the industrialized world excess of vitamin A has been suggested to be a risk factor for secondary osteoporosis and enhanced susceptibility to fractures. Preclinical studies unequivocally have shown that increased amounts of vitamin A cause decreased cortical bone mass and weaker bones due to enhanced periosteal bone resorption. Initial clinical studies demonstrated a negative association between intake of vitamin A, as well as serum levels of vitamin A, and bone mass and fracture susceptibility. In some studies, these observations have been confirmed, but in other studies no such associations have been observed. One meta-analysis found that both low and high serum levels of vitamin A were associated with increased relative risk of hip fractures. Another meta-analysis also found that low levels of serum vitamin A increased the risk for hip fracture but could not find any association with high serum levels of vitamin A and hip fracture. It is apparent that more clinical studies, including large numbers of incident fractures, are needed to determine which levels of vitamin A that are harmful or beneficial for bone mass and fracture. It is the aim of the present review to describe how vitamin A was discovered and how vitamin A is absorbed, metabolized and is acting as a ligand for nuclear receptors. The effects by vitamin A in preclinical studies are summarized and the clinical investigations studying the effect by vitamin A on bone mass and fracture susceptibility are discussed in detail.
Assuntos
Densidade Óssea , Fraturas Ósseas , Vitamina A , Humanos , Vitamina A/metabolismo , Vitamina A/sangue , Animais , Fraturas Ósseas/metabolismo , Fraturas Ósseas/etiologia , Fraturas Ósseas/epidemiologia , Transdução de Sinais , Osteoporose/metabolismo , Deficiência de Vitamina A/metabolismo , Deficiência de Vitamina A/complicações , Osso e Ossos/metabolismoRESUMO
BACKGROUND: Vitamin A deficiency (VAD) is a leading contributor to the poor health and nutrition of young children in sub-Saharan Africa. Funding constraints are compelling many countries to shift from longstanding campaigns to integrating vitamin A supplementation (VAS) into routine health services. We assessed child VAS coverage and associated factors for integrated delivery systems in Mozambique, Senegal, and Sierra Leone and for a campaign-based delivery strategy in Tanzania. METHODS: Data were obtained using representative household surveys administered to primary caregivers of N = 16,343 children aged 6-59 months (Mozambique: N = 1,659; Senegal: N = 7,254; Sierra Leone: N = 4,149; Tanzania: N = 3,281). Single-dose VAS coverage was assessed and bivariate and multivariable associations were examined for child VAS receipt with respect to rural or urban residence; child age and sex; maternal age, education, and VAS program knowledge; and household wealth. RESULTS: VAS coverage for children aged 6-59 months was 42.8% (95% CI: 40.2, 45.6) in Mozambique, 46.1% (95% CI: 44.9, 47.4) in Senegal, 86.9% (95% CI: 85.8, 87.9) in Sierra Leone, and 42.4% (95% CI: 40.2, 44.6) in Tanzania and was significantly higher for children 6-11 vs. 24-59 months in Mozambique, Senegal, and Tanzania. In Sierra Leone, children aged 12-23 months (aOR = 1.86; 95% CI: 1.20, 2.86) and 24-59 months (aOR = 1.55; 95% CI: 1.07, 2.25) were more likely to receive VAS, compared to those 6-11 months. Maternal awareness of VAS programs was associated with higher uptake in Mozambique (aOR = 4.00; 95% CI: 2.81, 5.68), Senegal (aOR = 2.72; 95% CI: 2.35, 3.15), and Tanzania (aOR = 14.50; 95% CI: 10.98, 19.17). Increased household wealth was associated with a higher likelihood of child VAS in Senegal and Tanzania. CONCLUSIONS: Our findings indicate routine delivery approaches for VAS are not achieving the level of coverage needed for public health impact in these settings. Intensive outreach efforts contributed to the higher coverage in Sierra Leone and highlight the importance of reducing the burdens associated with seeking supplementation at health facilities. As countries move towards incorporating VAS into routine health services, the essentiality of informed communities and potential losses for older children and socio-economically disadvantaged populations are key considerations in the sub-Saharan African context.
Assuntos
Suplementos Nutricionais , Deficiência de Vitamina A , Vitamina A , Humanos , Lactente , Feminino , Masculino , Pré-Escolar , Suplementos Nutricionais/estatística & dados numéricos , África Subsaariana , Deficiência de Vitamina A/prevenção & controle , Deficiência de Vitamina A/tratamento farmacológico , Deficiência de Vitamina A/epidemiologia , Vitamina A/administração & dosagem , Vitamina A/uso terapêutico , Prestação Integrada de Cuidados de Saúde , Adulto , Promoção da Saúde/métodos , MoçambiqueRESUMO
PURPOSE: This review examined existing literature to determine various ocular manifestations of liver pathologies, with a focus on metabolic deficiencies as well as viral and immune liver conditions. METHODS: Recent data were compiled from PubMed from 2000 to 2020 using keywords that were relevant to the assessed pathologies. Ocular presentations of several liver pathologies were researched and then summarized in a comprehensive form. RESULTS: Several ocular manifestations of liver disease were related to vitamin A deficiency, as liver disease is associated with impaired vitamin A homeostasis. Alcoholic liver cirrhosis can result in vitamin A deficiency, presenting with Bitot spots, xerosis, and corneal necrosis. Congenital liver diseases such as mucopolysaccharidoses and peroxisomal disorders are also linked with ocular signs. Viral causes of liver disease have associations with conditions like retinal vasculitis, keratoconjunctivitis sicca, retinopathies, Mooren's ulcer, and Sjogren's syndrome. Autoimmune hepatitis has been linked to peripheral ulcerative keratitis and uveitis. CONCLUSIONS: Building strong associations between ocular and liver pathology will allow for early detection of such conditions, leading to the early implementation of management strategies. While this review outlines several of the existing connections between hepatic and ophthalmic disease, further research is needed in the area in order to strengthen these associations.
Assuntos
Úlcera da Córnea , Síndromes do Olho Seco , Ceratoconjuntivite Seca , Hepatopatias , Vasculite Retiniana , Síndrome de Sjogren , Deficiência de Vitamina A , Humanos , Deficiência de Vitamina A/complicações , Ceratoconjuntivite Seca/etiologia , Úlcera da Córnea/diagnóstico , Síndrome de Sjogren/complicações , Síndromes do Olho Seco/complicações , Hepatopatias/etiologia , Hepatopatias/complicações , Vasculite Retiniana/complicaçõesRESUMO
This case study reports on the presence of vitamin A deficiency in an adult with asymmetric normal tension glaucoma. The retinal OCT findings demonstrated not only expected loss of the outer retinal layers, typically seen in vitamin A deficiency, but also severe and bilateral loss of the inner retinal layers. After vitamin A supplementation, visual acuity, dark adaptation, and color vision normalized. The outer retinal layers had a restoration of thickness after vitamin A supplementation, but the inner layers did not change. This case is unique because it may give us an insight into the role of vitamin A on the inner retina and demonstrate the recovery of the outer retinal layers with vitamin A supplementation.
Assuntos
Pressão Intraocular , Tomografia de Coerência Óptica , Acuidade Visual , Deficiência de Vitamina A , Vitamina A , Humanos , Tomografia de Coerência Óptica/métodos , Deficiência de Vitamina A/complicações , Deficiência de Vitamina A/diagnóstico , Vitamina A/administração & dosagem , Acuidade Visual/fisiologia , Pressão Intraocular/fisiologia , Glaucoma de Baixa Tensão/diagnóstico , Glaucoma de Baixa Tensão/complicações , Pessoa de Meia-Idade , Feminino , Masculino , Células Ganglionares da Retina/patologia , Vitaminas/administração & dosagem , Adaptação à Escuridão/fisiologia , Campos Visuais/fisiologiaRESUMO
In the developing world, the twin challenges of depleted health and growing issue of food waste management loom large, demanding simultaneous attention and innovative solutions. This review explores how these issues can be effectively mitigated while shedding light on the transformative impact of food waste valorization on health management. A spotlight is cast on vitamin A deficiency (VAD), an acute public health concern, especially prevalent in South Asia, driven by economic constraints, sociocultural factors, inadequate diets, and poor nutrient absorption. VAD's devastating effects are exacerbated by limited education, lack of sanitation, ineffective food regulations, and fragile monitoring systems, disproportionately affecting children and women of childbearing age. Recent studies in South Asian countries have revealed rising rates of illness and death, notably among children and women of childbearing age, due to VAD. To address inadequate dietary intake in children utilizing vegetable waste, particularly from carrots and beetroot, which are rich in ß-carotene, and betalains, respectively, offers a sustainable solution. Extracting these compounds from vegetable waste for supplementation, fortification, and dietary diversification could significantly improve public health, addressing both food waste and health disparities economically. This approach presents a compelling avenue for exploration and implementation. In summary, this review presents an integrated approach to tackle health and food waste challenges in the developing world. By tapping into the nutritional treasure troves within vegetable waste, we can enhance health outcomes while addressing food waste, forging a brighter and healthier future for communities in need.
Assuntos
Deficiência de Vitamina A , Humanos , Deficiência de Vitamina A/epidemiologia , Ásia , Dieta/métodos , Dieta/estatística & dados numéricos , Vitamina A/administração & dosagem , Feminino , Verduras , Criança , Países em Desenvolvimento , Ásia MeridionalRESUMO
BACKGROUND: Evidence of the effectiveness of biofortified maize with higher provitamin A (PVA) to address vitamin A deficiency in rural Africa remains scant. OBJECTIVES: This study projects the impact of adopting PVA maize for a diversity of households in an area typical of rural Zimbabwe and models the cost and composition of diets adequate in vitamin A. METHODS: Household-level weighed food records were generated from 30 rural households during a week in April and November 2021. Weekly household intakes were calculated, as well as indicative costs of diets using data from market surveys. The impact of PVA maize adoption was modeled assuming all maize products contained observed vitamin A concentrations. The composition and cost of the least expensive indicative diets adequate in vitamin A were calculated using linear programming. RESULTS: Very few households would reach adequate intake of vitamin A with the consumption of PVA maize. However, from a current situation of 33%, 50%-70% of households were projected to reach ≥50% of their requirements (the target of PVA), even with the modest vitamin A concentrations achieved on-farm (mean of 28.3 µg RAE per 100 g). This proportion would increase if higher concentrations recorded on-station were achieved. The estimated daily costs of current diets (mean ± standard deviation) were USD 1.43 ± 0.59 in the wet season and USD 0.96 ± 0.40 in the dry season. By comparison, optimization models suggest that diets adequate in vitamin A could be achieved at daily costs of USD 0.97 and USD 0.79 in the wet and dry seasons, respectively. CONCLUSIONS: The adoption of PVA maize would bring a substantial improvement in vitamin A intake in rural Zimbabwe but should be combined with other interventions (e.g., diet diversification) to fully address vitamin A deficiency.