Relationship between vitamin D and abdominal obesity in non-diabetic population in Taiyuan community / 中华临床营养杂志

ABSTRACT

Objective To evaluate the serum 25-hydroxyvitamin D [25 (OH)D3] levels in non-diabetic people in Taiyuan community,and its relationship with obesity and abdominal obesity.Methods This crosssectional study enrolled 417 non-diabetic people in Tainyuan community from July to September in 2011 [225 males and 192 females,mean age (47.6 ±7.8) years].For all the enrolled subjects,we collected data about anthropometric indexes,medical history,blood glucose,lipid profile,25 (OH) D3,fasting insulin (Fins) level,homeostasis model assessement for insulin resistance (HOMA-IR),body fat content (％) measured with dualenergy X-ray absorptiometry (DEXA),and intra-abdominal adipose tissue (IAAT) and abdominal subcutaneous adipose tissue (SCAT) calculated based on magnetic resonance imaging at the 4th to 5th lumbar disc level (IAAT≥80 cm2 was considered abdominal obesity).Correlation analysis was performed to assess the relationships of serum 25 (OH) D3 levels with biochemical and body fat indexes.Results The average serum level of 25 (OH) D3 was 44.5 nmol/L in the 417 people,with vitamin D deficiency in 261 cases (62.6％) and vitamin D insufficiency in 109 cases (26.1％).Of the vitamin D deficient and insufficient people,77.6％ had abdominal obesity according to IAAT (IAAT ≥ 80 cm2).According to Pearson analysis result,lg 25 (OH)D3 was negatively correlated with lg Fins,lg HOMA-IR,waist circumference,systolic blood pressure,diastolic blood pressure,total abdominal adipose tissue (TAAT),IAAT (all P ＜0.05).It was also negatively correlated with waist-to-hip-ratio,body mass index (BMI),and body fat content (％),but without statistical significance (all P ＞0.05).In stepwise multiple linear regression model,lg HOMA-IR (t =-4.278,P =0.001) and TAAT (t =-5.146,P =0.002) were independently correlated with lg 25 (OH) D3.Conclusions About 90％ of all non-diabetic population in Taiyuan community have vitamin D deficiency or insufficiency,of whom 4/5 have abdominal obesity.Serum 25 (OH)D3 level is negatively correlated with abdominal adipose tissue,but not significantly associated with BMI.HOMA-IR and TAAT are independent risk factors for vitamin D deficiency.