Abstract P427: Vitamin D Deficiency and Cardiovascular Disease (CVD) Risk Factors in American Indian Adolescents: The Strong Heart Family Study

Abstract

Introduction: Vitamin D deficiency (VDD) may be associated with CVD risk factors, such as obesity, diabetes, and dyslipidemia and is amenable to successful interventions through changes in diet and vitamin supplementation. Aims: To describe the prevalence of VDD among American Indian adolescents from SHFS and determine its association with obesity, diabetes, and dyslipidemia incidence in follow-up exams. Methods: We included adolescents (<20 years) from the SHFS, who had serum vitamin D measured on stored samples collected at the baseline examination, 2001-2003 (n=307). We defined VDD as ≤20ng/mL and obesity as baseline Body Mass Index (BMI) ≥95%, follow-up BMI ≥30kg/m 2 , waist-hip-ratio (WHR) ≥0.9 for males, or WHR ≥0.85 for females. Diabetes was defined as measured fasting plasma glucose level ≥126 mg/dL or taking hypoglycemic medication. We defined dyslipidemia as abnormal total cholesterol, LDL-C, HDL-C, non-HDL-C, triglycerides, or taking medication. We used log binomial generalized estimating equations to determine if the prevalence or incidence of obesity, diabetes, or dyslipidemia differed according to VDD, while controlling for age, gender, and center (Arizona, Oklahoma, or Dakotas). Results: VDD prevalence was 50.8% in AI adolescents, and it was associated with the prevalence of BMI≥95%, high WHR, and dyslipidemia. By the first follow-up, 28.8% developed a BMI≥30kg/m 2 , 58.8% developed high WHR, 6.2% developed diabetes, and 62.6% developed dyslipidemia. By the second follow-up, 11.4% developed diabetes. The risk of high WHR (RR=1.28, CI=1.04-1.58, follow-up=5.8 years), and the risk of diabetes (RR=2.32, CI=1.05-5.12, follow-up=13.3 years) was higher in those with baseline VDD while controlling for covariates (Table 1). Conclusions: These data suggest that VDD in adolescence may contribute to the development of high WHR and diabetes later in life, which are strongly associated with CVD. Thus, the results of this analysis may provide a critical step toward reducing or controlling CVD at an early age.