Gender differences in associations of serum ferritin and diabetes, metabolic syndrome, and obesity in the China Health and Nutrition Survey

Scope: This study examines gender differences in associations of serum ferritin and diabetes, metabolic syndrome (MetS), and obesity in Chinese. Methods and results: Based on a nationwide, population-based China Health and Nutrition survey this study included 8564 men and women aged 18 years or older. Anthropometric and fasting blood glucose, insulin, lipids, ferritin, and transferrin data were collected. Ferritin concentrations were higher in men than women (201.55 +/- 3.6 versus 80.46 +/- 1.64 ng/mL, p < 0.0001). The prevalences of MetS, diabetes, obesity, and overweight were 8.05, 8.97, 4.67, 25.88% among men and 14.23, 6.58, 5.81, 26.82% among women, respectively. Elevated ferritin concentrations were associated with higher body mass index, waist circumference, lipids, insulin, glucose (all p < 0.0001). Serum ferritin concentrations increased gradually with aging among women. The inverted U-shaped association between serum ferritin and age was observed among men. Elevated concentration of ferritins were significantly related with higher risk of MetS (p < 0.0001), obesity (p = 0.010), overweight (p < 0.0001), and diabetes (p < 0.0001) among men, but not among women. Conclusion: There was a gender difference in associations between ferritin and MetS, obesity, and diabetes in Chinese adults. Further evaluations of the variation in gender on these associations are warranted to understand the mechanisms behind gender differences.