Sex dimorphisms in inflammatory markers and adiposity in African-American youth.

OBJECTIVE: There are demonstrated sex differences in the association between adiposity and inflammation in adults. Our aim was to determine sex differences in inflammatory markers and in the association between adiposity and inflammation in a sample of African-American adolescents. METHODS: Adiposity variables including body mass index (BMI), waist circumference, weight, total fat, trunk fat, and inflammatory markers including interleukin-6 (IL-6), leptin, monocyte chemotactic protein 1 (MCP1), C-reactive Protein (CRP), adiponectin were examined in 166 (53% female) African-American adolescents, aged 14-19 years. Total fat and trunk fat were measured using Dual-Energy X-ray Absorptiometry (DXA). RESULTS: Results revealed males had higher weight (p=0.01); females had higher BMI, trunk fat, and total fat (p's <0.01). With inflammation, males had higher MCP1 (p=0.024); females had higher leptin (p<0.001), adiponectin (p=0.006), and IL-6 (p=0.026). Partial correlations in males indicated associations of adiposity variables with leptin, adiponectin (all p's <0.01), and CRP (p<0.05); in females, leptin, CRP, and IL-6 were associated with adiposity variables (all p's <0.05). multiple regression analyses revealed female adiposity variables predicted CRP, (R(2)=0.254), IL-6 (R(2)=0.167), and MCP1 (R(2)=0.220). Adiposity variables in males predicted lower adiponectin (R(2)=0245). For both, leptin was predicted by adiposity (males R(2)=0.420 and females R(2)=0.410). CONCLUSIONS: Data indicate clear sex dimorphisms in the associations between inflammatory markers and adiposity in African-American adolescents, suggesting that preventive measures and treatments for adolescent obesity may need to be sex-specific.