journal articles
VITAMIN D DEFICIENCY/INSUFFICIENCY AND OBESITY AND METABOLIC DISORDERS IN COMMUNITY-LIVING CHILEAN ELDERLY PEOPLE
B. Angel, H. Sanchez, L. Lera, X. Cea, C. Albala
J Aging Res Clin Practice 2013;2(3):251-256
Background: Objective: To examine obesity and metabolic disorders associated with vitamin D (VitD) deficiency/insufficiency in community-living Chilean older people. Methods: Cross sectional study in 1186 community dwelling subjects 60-98 years old (807 women) residing in Santiago Chile. Plasma levels of 25-hydroxyvitamin D (25(OH)D) were determined by radioimmunoassay. Glucose, insulin and US-CRP, were measured in a fasting blood sample. Blood pressure and complete anthropometry were evaluated. Diabetes was defined as ≥ 126 mg/dl or use of anti-diabetic agents, fasting glucose intolerance (FGI) was defined as glucose ≥100 mg/dL and insulin resistance as HOMA-IR ≥ 2.6. VitD deficiency was defined as a serum 25(OH)D concentration <50 nmol/L and VitD insufficiency as 50-74 nmol/L. The relationship between VitD and metabolic disorders was studied using multivariable logistic regression models. Results: Mean serum 25(OH)D was 63.2 nmol/L ± 33.1 (men 66.0 ± 33.0; women 62.0 ± 33.2, p=0.48) the lowest in people ≥70 years (55.8 ± 26.6). VitD levels were under 75nmol/L in 67.0% of men and 73.0% of women (p=0.020). The prevalence of VitD deficiency was 36.5% in men and more prevalent in women 40.8% (p=0.045). Obesity was present in 37.6% of women and 26.3% of men p<0.001. Significant negative crude association between VitD across BMI categories was found in the total sample (p<0.001). Crude association of VitD <50nmol/L with obesity (p=0.002), waist circumference (p=0.011), Insulin resistance (p<0.001), Metabolic syndrome (p=0.004), HTA (p<0.001) and Age ≥ 70 years (p<0.001) was observed. After adjustment by age, sex, waist circumference and season, VitD <50nmol/L was associated with increased risk of insulin resistance, OR 3.12 (95%CI 1.66 – 5.86), p<0.001. Conclusion: High prevalence of VitD deficiency/insufficiency was observed in the Chilean older people. VitD deficiency is associated with insulin resistance. In the future, randomized controlled trials are needed to establish a cause-effect relationship between VitD deficiency, obesity and its metabolic consequences.