The Correlation Between Circulating Fetuin-A Levels and Fetuin-A to Adiponectin Ratio With Obesity in a Turkish Population: A Case-Control Study

The relationship between serum fetuin-A levels and obesity has not been fully understood. This study aims to elucidate the levels of serum fetuin-A and F/A ratio in obesity and contribute to the literature on whether they could be novel clinical predictors modulated through body composition and nutrition. The study included 73 participants who were obese and 71 participants with normal weight, aged between 18 and 65 years. Certain anthropometric measurements of the individuals were taken, and a body composition analysis was performed. In addition, 3-day food records (consecutive days: 2 weekdays and one weekend day) were taken. Serum levels of fetuin-A (ng/mL) and adiponectin (μg/mL) were measured using an enzyme-linked immunosorbent assay (ELISA) method. The F/A ratio was obtained by dividing fetuin-A (ng/mL) by adiponectin (μg/mL). Serum fetuin-A (ng/mL) level and F/A ratio are higher in obese participants than in normal weight (p < 0.05). Body weight (kg) (r = 0.553, p ≤ 0.001), body mass index (kg/m2) (r = 0.492, p ≤ 0.001), waist circumference (cm) (r = 0.522, p ≤ 0.001), body fat percentage (%) (r = 0.203, p = 0.015), serum fasting blood glucose levels (mg/dL) (r = 0.317, p ≤ 0.001), and dietary protein intake (kg) (r = 0.165, p = 0.048) were observed to be positively correlated with serum fetuin-A levels. Positive correlations were also observed between these parameters and the F/A ratio (p < 0.05). Negative correlations were found between serum adiponectin and these parameters (p < 0.05). In addition, when dietary cholesterol intake was kept constant, a 1-unit increase in dietary energy intake (kcal) resulted in a 0.043-fold increase in serum fetuin-A (p < 0.05). The study results support theories suggesting the involvement of serum fetuin-A levels and the F/A ratio in the pathogenesis of obesity. The higher serum fetuin-A levels and F/A ratio found in obese participants may be considered as new clinical determinants that could be regulated through body composition and nutrition.