Association Between Serum Vitamin D Levels And Lipid Profiles Among Medium-elderly Individuals In Beijing

ObjectiveTo investigate the Vitamin D(25(OH)D) status of medium-elderly population in Beijing, analyze the correlation of serum 25(OH)D levels and dyslipidemia risk and explore the effect of Vitamin D supplementation on lipid profiles.Methods1.448 cases of individuals over 40 years old had been enrolled for the cross-sectional survey. They were conducted through questionnaires, physical examination and blood tests. The clinic history, life style, levels of serum 25(OH)D and lipid profiles and other information were gathered. To compare 25(OH)D levels, subjects were divided to dyslipidemia group and non-dyslipidemia group. According to quartiles of 25(OH)D, subjects were divided into four groups to compare lipid profiles. The correlation of 25(OH)D levels and dyslipidemia risk was analyzed by logistic regression analysis.2.106 subjects with 25(OH)D below 30ng/ml were randomly recruited from the above baseline population and were divided into control group and experimental group at random. The control group was given daily life guidance while the experimental group was given 5000 IU/day of vitamin D for ones with vitamin D insufficiency,1000 IU/day for ones with vitamin D deficiency,15000 IU/day for ones with vitamin D severe deficiency for 9 months. The general data of same group before and after the intervention were compared with paired t test. The general data between the two groups were compared with independent sample t test.Result1. The mean value of serum 25(OH)D was (17.54 ± 7.80)ng/mL. The proportion of 25(OH)D deficiency was 91.07%. The percent of dyslipidemia was 52.23%. Dyslipidemia group's 25(OH)D of different gender was significantly lower than non-dyslipidemia group's(P<0.05).As quartiles of 25(OH)D levels increased, the prevalence of dyslipidemia, total cholesterol, triglyceride and low density lipoprotein cholesterol decreased and high density lipoprotein cholesterol increased(P<0.05). The logistic regression analysis showed that after adjustment for confounding factors, the dyslipidemia's risk of the lowest 25(OH)D quartile group was higher than the highest quartile group's.2. Finally there were 100 cases included in the statistical analysis of the prospective study. The intervention successful rate of adequate vitamin D in the experimental group was 72%.There was a significant increase in the mean value of 25(OH)D level after supplementation in the experimental group (baseline level 15.27±4.49ng/ml vs after supplement level 33.18±7.18ng/ml, p<0.001). After intervention, TC and LDL-C level of the experimental group were lower than the control group(p<0.05). LDL-C level were significantly decreased after supplementation in the experimental group(p=0.024).ConclusionThese findings indicate that the 25(OH)D insufficiency is highly prevalent among medium-elderly individuals. The condition was more serious in dyslipidemia patients. Lower vitamin D may increase dyslipidemia risk. Different doses of vitamin D supplement according to the different nutrition diagnosis stratification can significantly improve vitamin D deficiency status and lower levels of TC and LDL-C.