Vitamin D and risk of developing type 2 diabetes in the SUN project: a prospective cohort study.

PURPOSE: Vitamin D deficiency has been associated with multiple chronic diseases, including metabolic disorders such as insulin resistance and type 2 diabetes (T2D). The aim of the study was to analyze the association between validated predicted serum vitamin D status and the risk of developing T2D in a large prospective cohort based on a Mediterranean population. METHODS: The SUN project is a prospective and dynamic Spanish cohort that gathers university graduates who have answered lifestyle questionnaires, including a validated Food Frequency Questionnaire. The association between predicted serum vitamin D and the risk of T2D was assessed through Cox regression models according to quartiles (Q) of predicted vitamin D at baseline. The models were adjusted for potential confounders and sensitivity analyses were performed to ensure the robustness of our findings. RESULTS: Our study included a total of 18,594 participants and after a total follow-up of 238,078 person-years (median follow-up of 13.5 years), 209 individuals were diagnosed with incident T2D. We found a significant inverse association between predicted levels of serum vitamin D and the risk of developing T2D, after adjusting for potential confounders and performing different sensitivity analyses (hazard ratio Q4 vs. Q1: 0.48, 95% CI 0.26-0.88; p for trend = 0.032). CONCLUSION: The outcomes suggest that higher levels of vitamin D at baseline may be associated with a reduced risk of developing T2D.

The risk of incident depression when assessed with the Lifestyle and Well-Being Index.

OBJECTIVES: Novel findings indicate links between unhealthy lifestyles and depression based on active inflammatory processes. Thus, identifying participants with poor habits could reveal differences in trends of incident depression. This study aimed to examine the association between an objective lifestyle assessment, as measured by the Lifestyle and Well-Being Index (LWB-I), and incident depression in healthy participants of a Spanish cohort. STUDY DESIGN: This was a longitudinal analysis of a subsample of 10,063 participants from the Seguimiento Universidad de Navarra cohort study. METHODS: Group comparisons and Cox proportional hazard models were conducted using the LWB-I, which categorizes the sample into groups with healthy and unhealthy lifestyles and well-being. The main outcome was incident depression as well as secondary outcomes. RESULTS: Those classified to the transition category of LWB-I were associated with a hazard ratio of 0.67 (95% confidence interval: 0.52-0.87), and those in the excellent category showed a hazard ratio of 0.44 (95% confidence interval: 0.33-0.58), which in both groups reflects a significantly lower risk of incident depression compared with the group including those classified in the poor LWB-I level. Moreover, the available sensitivity analyses concerning time of depression diagnosis or antidepressant treatment further supported the role of nutrition and physical activity on incident depression. Interestingly, throughout the follow-up, incident depression was inversely related to healthier daily habits as measured by the LWB-I. CONCLUSIONS: A global assessment of lifestyles such as the LWB-I provides valuable insight into the complex relationship between lifestyle factors and their link to depression risk.

A U-shaped protection of altitude against mortality and infection of COVID-19 in Peru: an ecological study.

BACKGROUND: The COVID-19 pandemic has affected the world in multiple ways and has been a challenge for the health systems of each country. From the beginning, risk factors for the severity and mortality of the disease were considered, as the spread of the virus was related to the living conditions of each population. METHODS: In this ecological study we have evaluated the role of geography, precisely the altitude above sea level in the incidence and mortality of COVID-19 in Peru. Incidence and mortality data were taken from the open-access database of the government of Peru until March 2021. COVID-19 cases and COVID-19 mortality were treated as cases/density population and 1000 x cases/inhabitants while altitude was treated as continuous and as a categorical variable divided in 7 categories. The relationship between COVID-19 cases or deaths for COVID-19 and altitude as continuous variable was determined using Spearman correlation test. Meanwhile when altitude was considered as a categorical variable, Poisson regression or negative binomial analyses were applied. RESULTS: A significant inverse correlation was found between COVID-19 cases by population density and altitude (r=-0.37 p < 0.001). By altitude categories, the lowest risk for infection was observed between 3,000 and 3,500 m (IRR 0.08; 95% CI 0.05,0.12). Moreover, we found an inverse correlation between altitude and COVID-19 mortality (r=-0.39 p < 0.001). Also, the lowest risk for mortality was observed between 3,000 and 3,500 m (IRR 0.12; 95%CI 0.08; 0.18). Similar results were found when analyses were adjusted for inhabitants and stratified by sex. CONCLUSION: This study reports an inverse relationship between COVID-19 incidence and mortality with respect to the altitude of residence, particularly, a u-shaped protection is shown, with a highest benefit between 3000 and 3500 m. The possibility of using hypoxia as an alternative treatment requires more complex studies that should allow knowing the physiological and environmental mechanisms of the protective role.

Depression and metabolic syndrome in participants of the "Seguimiento Universidad de Navarra" (SUN) cohort study.

BACKGROUND: Depression is a major public health concern worldwide and its association with metabolic syndrome (MetS) remains unclear. Thus, we prospectively examined the association between depression and the risk of MetS, according to different diagnosis criteria. METHODS: This study included 9,237 participants of a Spanish dynamic prospective cohort of adult university graduates [mean (SD) age: 36.7 year (10.7)], initially free of any specific criterion of MetS, who were followed-up for a median of 8.3 years. The exposure variables were medical diagnosis of depression at baseline or in the first 2-year follow-up questionnaire. The outcome variable was the incidence of MetS, assessed according to each of three different criteria proposed by: International Diabetes Federation (IDF); National Cholesterol Education Program's Adult Treatment Panel III (NCEP-ATP III); IDF/NCEP-ATP III (updated harmonizing definition). Multivariable-adjusted Relative Risks (RR) of new-onset MetS and their 95% Confidence Intervals (95% CI) were estimated, using Poisson regression models. RESULTS: The cumulative incidences of MetS were 475 cases (IDF definition), 288 cases (NCEP-ATP III definition) and 492 cases (update harmonized definition). No association was observed between baseline depression and incidence of MetS, but the presence of depression after 2-years of follow-up was significantly associated with a higher risk of new-onset MetS, according to NCEP-ATP III definition (multivariable-adjusted RR, 2.46; 95% CI, 1.06-5.67). LIMITATIONS: Diagnosis of depression and MetS were self-reported. CONCLUSIONS: In this large prospective cohort of Spanish middle-aged adult university graduates, a direct association between depression and the risk of MetS according to NCEP-ATP III definition was found.

Body shape trajectories and incidence of depression in the "Seguimiento Universidad de Navarra" (SUN) prospective cohort.

BACKGROUNDS AND AIM: The association between trajectories of body-shape from early childhood to early adulthood (first 40 years of life) and subsequent depression risk has not been explored before. We assessed this association in a prospective cohort of university graduates. METHODS: We used a group-based modeling approach to assess the body shape trajectories from age 5 to 40 years, among 3888 women and 4124 men of the "Seguimiento Universidad de Navarra" (SUN) cohort study. All participants were free of depression at the beginning of the follow-up, and the occurrence of a new medical diagnosis of depression was evaluated every two years. RESULTS: Four distinct trajectories for women and men were found ("lean-moderate increase", "medium-stable", "heavy-medium" and "heavy-marked increase" for women and "lean-marked increase", "medium-marked increase", "medium-stable" and "heavy-stable" for men). Among 78,475 person-years of follow-up a total of 351 incident cases of depression were identified. Among women, compared to those who maintained a medium body shape during life span ("medium-stable" trajectory), women who were heavy at childhood and had a marked increase in their body shape during early adult life ("heavy-marked increase" trajectory) showed significantly higher risk of a new-onset depression [HR = 1.92 (1.18-3.13)]. No association was observed in men between body-shape trajectories and subsequent risk of depression. CONCLUSIONS: Our results suggest that in a Mediterranean cohort, women who were heavy at early childhood and showed marked increases in body shape during early adulthood were at higher risk of developing depression later in life.

Body shape trajectories and the incidence of hypertension in a Mediterranean cohort: The sun study.

AIMS: Our aim was to assess the association between trajectories of body-shape across the first 40 years of life and subsequent development of hypertension in a Mediterranean cohort. METHODS AND RESULTS: We used a group-based modeling approach to assess body shape trajectories from age 5 to 40 years, among 7514 participants included in the SUN study (1999-2016), and assessed the subsequent incidence of hypertension. To create the trajectories, we used a censored normal model as a polynomial function of age. Cox models were used to estimates hazard ratios (HR) for hypertension according to body shape trajectories. Identified trajectories were "childhood lean -mid-life increase", "childhood medium-mid-life stable", " childhood heavy -mid-life decrease", and "childhood heavy -mid-life increase" for women; and "childhood lean-mid-life increase", "childhood medium-mid-life stable", "childhood medium -mid-life increase" and "childhood heavy-mid-life stable" for men. After a follow-up of 63,068 person-years, 865 incident cases of hypertension were found. Among women, compared to those in the "childhood medium-mid-life stable" trajectory, those, in the "childhood heavy -mid-life increase" trajectory showed higher risk to develop hypertension [HR = 1.72 (1.17-2.53)]. In men, compared with those in the "childhood medium-mid-life stable" trajectory, those in the "childhood lean and childhood medium -mid-life increase" and the "childhood heavy- mid-life stable" trajectories showed higher subsequent incidence of hypertension [HR = 1.43 (1.11-1.85), HR = 1.52 (1.17-1.97) and HR = 1.56 (1.14-2.14), respectively] after adjusting for potential confounders (including age, lifestyles, dietary intake, personality traits, physical activity and sedentary behaviors). CONCLUSIONS: Our results suggest that mid-life increases in body shape or maintaining a heavy body shape during early and middle life in men and childhood heavy-mid-life increase in women is associated with a higher subsequent risk of developing hypertension in this Mediterranean population.

Yogurt consumption and abdominal obesity reversion in the PREDIMED study.

BACKGROUND AND AIMS: Evidence on the association yogurt consumption and obesity is not conclusive. The aim of this study was to prospectively evaluate the association between yogurt consumption, reversion of abdominal obesity status and waist circumference change in elderly. METHODS AND RESULTS: 4545 individuals at high cardiovascular risk were prospectively followed. Total, whole-fat and low-fat yogurt consumption were assessed using food frequency questionnaires. Generalized estimating equations were used to analyze the association between yogurt consumption and waist circumference change (measured at baseline and yearly during the follow-up). Logistic regression models were used to evaluate the odds ratios (ORs) and 95% CIs of the reversion rate of abdominal obesity for each quintile of yogurt consumption compared with the lowest quintile. After multivariable adjustment, the average yearly waist circumference change in the quintiles of whole-fat yogurt consumption was: Q1: 0.00, Q2: 0.00 (-0.23 to 0.23), Q3: -0.15 (-0.42 to 0.13), Q4: 0.10 (-0.21 to 0.42), and Q5: -0.23 (-0.46 to -0.00) cm; p for trend = 0.05. The ORs for the reversion of abdominal obesity for whole-fat yogurt consumption were Q1: 1.00, Q2: 1.40 (1.04-1.90), Q3: 1.33 (0.94-1.89), Q4: 1.21 (0.83-1.77), and Q5: 1.43 (1.06-1.93); p for trend = 0.26. CONCLUSION: Total yogurt consumption was not significantly associated with reversion of abdominal obesity status and a lower waist circumference. However, consumption of whole-fat yogurt was associated with changes in waist circumference and higher probability for reversion of abdominal obesity. Therefore, it seems that whole-fat yogurt has more beneficial effects in management of abdominal obesity in elderly population at high cardiovascular risk.

Carbohydrate quality, weight change and incident obesity in a Mediterranean cohort: the SUN Project.

BACKGROUND/OBJECTIVES: To evaluate the association between the carbohydrate quality index (CQI) and weight change or incident overweight/obesity (body mass index ⩾25 kg/m(2)) in the 'Seguimiento Universidad de Navarra (SUN)' cohort. SUBJECTS/METHODS: A total of 8741 participants who were initially free of overweight/obesity were followed up for a median of 7.9 years. We evaluated at baseline the CQI according to four criteria: dietary fiber intake, glycemic index, whole grains/total grains ratio and solid carbohydrates/total carbohydrates ratio. Subjects were classified into quintiles according to CQI. Weight was recorded at baseline and updated every 2 years during follow-up. RESULTS: Increasing CQI of diet was not significantly associated with lower weight gain, although participants in the highest quintile had the lowest average crude weight gain (+211 g/year). We observed 1862 incident cases of overweight/obesity during follow-up. CQI was significantly associated (P for trend 0.006) with a lower risk of overweight/obesity; adjusted odds ratio for the fourth and fifth quintiles were 0.81 (95% confidence interval (CI): 0.66-0.99) and 0.74 (95% CI: 0.60-0.92), respectively. CONCLUSIONS: In this Mediterranean cohort, CQI showed a significant inverse association with the incidence of overweight/obesity, which highlights that carbohydrate intake guidelines related to obesity prevention should be focused on improving the CQI of the diet.

Yogurt consumption, weight change and risk of overweight/obesity: the SUN cohort study.

BACKGROUND AND AIMS: Epidemiological studies on the association between yogurt consumption and the risk of overweight/obesity are scarce. We prospectively examined the association of yogurt consumption with overweight/obesity and average annual weight gain. METHODS AND RESULTS: Prospective cohort study of 8516 men and women (mean age 37.1, SD: 10.8 y). Participants were followed-up every two years. Participants were classified in 5 categories of yogurt consumption at baseline: 0-2, >2-<5, 5-<7, 7 and ≥ 7 servings/week. Outcomes were: 1) average yearly weight change during follow-up; and 2) incidence of overweight/obesity. Linear regression models and Cox models were used to adjust for potential confounders. After a median follow-up of 6.6 years, 1860 incident cases of overweight/obesity were identified. A high (>7 servings/week) consumption of total and whole-fat yogurt was associated with lower incidence of overweight/obesity [multivariable adjusted hazard ratios = 0.80 (95% CI: 0.68-0.94); and 0.62 (0.47-0.82) respectively] in comparison with low consumption (0-2 servings/week). This inverse association was stronger among participants with higher fruit consumption. CONCLUSION: In this Mediterranean cohort, yogurt consumption was inversely associated with the incidence of overweight/obesity, especially among participants with higher fruit consumption.

Association between dietary intakes of PCBs and the risk of obesity: the SUN project.

BACKGROUND: Polychlorinated biphenyls (PCB) are persistent organic pollutants (POP) that are consumed because of their bioaccumulation through the food chain. Recent studies have suggested the implication of POPs in the development of metabolic diseases such as type 2 diabetes and obesity. However, this relationship is not entirely consistent, and has not been investigated in longitudinal studies. The purpose of this study was to prospectively examine the association between dietary intake of PCBs and the incidence of obesity in the Seguimiento Universidad de Navarra (SUN) Project. METHODS: Our study included 12 313 participants without obesity at baseline, who were followed-up for a median of 8.1 years. Dietary intakes of PCBs, expressed as WHO toxic equivalents, were assessed at baseline through a 136-item semiquantitative food-frequency questionnaire. The published concentration levels of PCBs measured in samples of food consumed in Spain were used to estimate intakes. Multivariable Cox regression models were fitted to estimate HRs and 95% CI for incident obesity. RESULTS: During follow-up, we observed 621 incident cases of obesity. After adjustment for total energy intake and additional adjustment for potential confounders, participants in the fifth quintile of PCBs intake were at higher risk of becoming obese (adjusted HR: 1.58; (95% CI 1.21 to 2.06)) compared to those in the first quintile. The linear trend test was statistically significant (p<0.001). CONCLUSIONS: Dietary intake of PCBs as estimated using a food frequency questionnaire was associated with a higher incidence of obesity. Nevertheless, further longitudinal studies are needed to confirm our results.

Consumption of fried foods and risk of metabolic syndrome: the SUN cohort study.

BACKGROUND & AIMS: There is scarce evidence from long-term prospective studies relating the consumption of fried foods with the incidence of Metabolic Syndrome (MS). The aim of this study was to assess the association between fried food consumption and the incidence of MS. METHODS: We followed 8289 participants (2813 men and 5476 women, mean age = 35.9 y, SD = 10.4) during a median period of 8.3-y. They were initially free of any MS criteria. MS was defined according to the American Heart Association and the International Diabetes Federation criteria as outlined in the harmonized definition for MS. Each component of the MS was assessed at the 6th and 8th-y of follow-up. The outcome was defined as the presence of ≥3 of the components of MS after ≥6 years of follow-up. RESULTS: During 65335 person-years, 420 incident cases of MS were identified. Frequent consumption of fried foods was not associated with the incidence of MS [HR = 0.98 (95% CI: 0.77-1.26) p for trend = 0.862]. However, two components of the MS, central adiposity and high blood pressure were positively associated with fried food consumption [HR for consumption >4 times/week compared with ≤2 times/week = 1.10 (95% CI: 1.01-1.19) (p for trend 0.022) and HR = 1.16 (95% CI: 1.02-1.32) (p for trend 0.011), respectively] after multivariable adjustment. CONCLUSIONS: In this Mediterranean cohort of relatively young adults, frequent consumption of fried foods was not associated with MS. Two out of five components of MS (central adiposity and high blood pressure) were positively associated with frequent fried food consumption.

Consumption of fried foods and weight gain in a Mediterranean cohort: the SUN project.

BACKGROUND AND AIMS: The consumption of fried foods is believed to be linked with obesity and higher weight gain, however, the evidence from long-term randomized trials or prospective epidemiological studies is scarce. Therefore, the aim of our study was to prospectively evaluate the association between the consumption of fried foods and weight change and the incidence of overweight/obesity in a Mediterranean cohort. METHODS AND RESULTS: Prospective cohort study of 9850 men and women with a mean age of 38.1 years (SD 11.4) were followed-up for a median of 6.1 years to assess average yearly change in body weight, and incidence of overweight/obesity. The consumption of fried foods was associated with higher weight gain, but the differences were of small magnitude and statistically non-significant. The incidence of overweight/obesity during follow-up was also assessed in the subset of 6821 participants with initial body mass index <25 kg/m(2) (initially free of overweight/obesity), after adjusting for potential confounders, the odds ratio for developing overweight/obesity among participants who consumed fried foods >4 times/week was 1.37 (95% confidence interval: 1.08 to 1.73) in comparison with those who consumed fried foods <2 times/week (p for trend = 0.02). CONCLUSION: In this Mediterranean prospective cohort, a more frequent consumption of fried foods at baseline was associated with a higher risk of subsequently developing overweight/obesity during follow-up.