présente après une nuit de jeûne une concentration plasmatique de glucose (FPG) supérieure à 125 mg·dL. â1 ... augmentation des moyennes de 25(OH)D et une diminution de la prévalence du prédiabète. ... Corresponding author: Jian Liu (e-mai: [email protected]). 264 ..... nhanes_03_04/l06vid_c_met_Vitamin_D.pdf.
264
Serum 25(OH) vitamin D level, femur length, and risk of type 2 diabetes among adults
Appl. Physiol. Nutr. Metab. Downloaded from www.nrcresearchpress.com by Brock University on 07/06/11 For personal use only.
Jian Liu, Hongzhuan Tan, and Brian Jeynes
Abstract: The objective of this study was to examine the relationship between serum 25-hydroxyvitamin-D (25(OH)D) and femur length (FL) and their risk in association with diabetes in adults. A total of 3983 adults aged 20+ years from the National Health and Nutrition Examination Survey (2001–2002, 2003–2004) who had no missing measurements of FL or 25(OH)D were used in this analysis. Diabetes was defined as either being diagnosed with diabetes or an overnight fasting plasma glucose of (FPG) > 125 mg·dL–1. Prediabetes was defined as having an FPG of 100 mg·dL–1 < FPG < 126 mg·dL–1. In addition, each individual was grouped into a sex-specified quintile of FL (Q1–Q5). Overall, approximately 11% of males and 9% of females had diabetes and 33% of males and 20% of females had prediabetes. Although the Pearson correlation between 25(OH)D and FL was weak, since FL changed from Q1 to Q5, the adjusted means of 25(OH)D in both sexes increased, while the adjusted means of FPG, insulin, glycohemoglobin, and the adjusted prevalence of diabetes were all decreased (p for trends 0.05), and were weakly associated in women (r = 0.07, p < 0.001). When adjusted for age and Published by NRC Research Press
266
Appl. Physiol. Nutr. Metab. Vol. 36, 2011
Appl. Physiol. Nutr. Metab. Downloaded from www.nrcresearchpress.com by Brock University on 07/06/11 For personal use only.
Table 1. Characteristics of 3983 subjects by sex, obtained from the National Health and Nutrition Examination Survey (2001–2002, 2003–2004).
Age, y Ethnics, % White Black Mexican American Other Current smoking, % Annual family income, % Less than $25 000 $25 000–$55 000 Over $55 000 Total MET for activity,* kcal·kg–1·h–1 Blood relatives with diabetes, % Serum 25-OH-vitamin D, ng·mL–1 Femur length, cm Waist circumference, cm Body mass index, kg·m–2 Fasting plasma glucose, mg·dL–1 Fasting insulin, uu·mL–1 Glycohemoglobin, % Diabetes, % Impaired fasting glucose, %
Males
Females
n = 2021 44.8 (0.5)
n = 1962 46.4 (0.6)
72.9 10.0 8.3 8.7 23.0
72.5 11.7 6.4 9.3 18.7
28.9 31.2 39.8 15.3 (0.4) 23.5 24.6 (0.5) 42.9 (0.1) 100.0 (0.4) 28.1 (0.1) 104.0 (0.6) 10.8 (0.4) 5.49 (0.02) 11.2 32.8
38.7 28.1 33.2 12.8 (0.5) 26.4 23.9 (0.6) 38.9 (0.1) 93.5 (0.4) 28.2 (0.2) 97.5 (0.7) 9.2 (0.2) 5.42 (0.02) 9.1 20.4
Note: Data are weighted means or weighted proportions. Values with parentheses are means (SE). *Only 2331 individuals had no missing value.
ethnicity, however, the correlation coefficients in both sexes were similar (r = 0.08, p < 0.001). For individuals grouped into quintiles by sex-specific cutoff points of femur length, the adjusted mean levels and p values of trends for 25(OH)D, glucose, insulin, and glycohemoglobin are presented in Table 2. After adjustment for age, ethnicity, smoking, family income, family history of diabetes, and waist circumference, the mean levels of 25(OH)D in both sexes increased when femur length increased. The mean levels of fasting glucose, insulin, and glycohemoglobin all decreased when the femur length increased. The prevalence of diabetes was decreased when the femur length increased (p for trends
