Plasma 25-hydroxyvitamin D Concentration and Metabolic Syndrome among Middle-aged and Elderly Chinese
- Ling Lu, MSc1,
- An Pan, MSc1,
- Frank B. Hu, MD, PhD2,
- Oscar H. Franco, MD, DSc, PhD3,
- Huaixing Li, PhD1,
- Xiaoying Li, MD4,
- Xilin Yang, PhD5,
- Yan Chen, PhD1,
- Zhijie Yu, PhD (zjyu{at}sibs.ac.cn)1 and
- Xu Lin, MD, PhD (xlin{at}sibs.ac.cn)1
- 1 Key Laboratory of Nutrition and Metabolism, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences and Graduate School of the Chinese Academy of Sciences, Shanghai, 200031, China
- 2 Departments of Nutrition and Epidemiology, Harvard School of Public Health, Boston, MA 02115, Massachusetts
- 3 Health Sciences Research Institute, University of Warwick, Coventry, CV4 7AL, United Kingdom
- 4 Shanghai Clinical Center for Endocrine and Metabolic Diseases, Shanghai Institute of Endocrinology and Metabolism, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
- 5 Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Hong Kong SAR, China
Abstract
Objective: To evaluate the association between 25-hydroxyvitamin D [25(OH)D] and metabolic syndrome (MetS) in Chinese population.
Research design and methods: Plasma 25(OH)D was measured in a cross-sectional sample of 1443 men and 1819 women aged 50-70 years from Beijing and Shanghai. MetS was defined according to the updated National Cholesterol Education Program Adult Treatment Panel III criteria for Asian Americans. Fasting plasma glucose, insulin, lipid profile, HbA1c and inflammatory markers were measured.
Results: The geometric mean of plasma 25(OH)D was 40.4 nmol/l and percentages of vitamin D deficiency [25(OH)D <50 nmol/l] and insufficiency (50 ≤25(OH)D <75 nmol/l) were 69.2% and 24.4%, respectively. Compared with the highest 25(OH)D quintile (≥57.7 nmol/l), the odds ratio for MetS in the lowest quintile (≤28.7 nmol/l) was 1.52 (95% CI 1.17-1.98, P for trend = 0.0002), after multiple adjustment. Significant inverse associations existed also between 25(OH)D and individual MetS components, plus HbA1c. Moreover, we observed significant inverse associations of 25(OH)D with fasting insulin and insulin resistance index (homeostasis model assessment of insulin resistance, HOMA-IR) in overweight and obese individuals (BMI ≥24 kg/m2), but not in their normal weight counterparts (test for interaction: P = 0.0363 and 0.0187 for insulin and HOMA-IR, respectively).
Conclusions: Vitamin D deficiency is common in the middle-aged and elderly Chinese and low 25(OH)D level is significantly associated with increased risk of having MetS and insulin resistance. Prospective studies and randomized clinical trials are warranted to determine the role of 25(OH)D in the development of MetS and related metabolic diseases.
Footnotes
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- Received February 14, 2009.
- Accepted April 4, 2009.
- Copyright © American Diabetes Association
