An association between body mass index and high-sensitivity C-reactive protein concentrations is influenced by age in community-dwelling persons

Abstract

High sensitivity C-reactive protein (hsCRP) is an acute phase reactant and a sensitive marker of inflammation. Age and adiposity can potentially promote the production of C-reactive protein (CRP). However, only a few studies have investigated any interaction between age and adiposity on hsCRP concentrations. We recruited 822 men (mean age, 61 ± 14 years) and 1097 women (63 ± 12 years) during their annual health examination from a single community. We cross-sectionally examined whether age, body mass index (BMI), and the interaction are significantly associated with hsCRP concentrations, independent of confounding factors. Multiple linear regression analyses for hsCRP showed that in men, age ( β = 0.169, P < 0.001) and BMI ( β = 0.114, P = 0.004) as well as smoking status, triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), uric acid, and gamma-glutamyl transferase (GGT) were significantly associated with hsCRP; and in women, age ( β = 0.203, P < 0.001) and BMI ( β = 0.225, P < 0.001) as well as HDL-C, fasting plasma glucose (FPG), uric acid, GGT and high-molecular weight adiponectin were significantly associated with hsCRP. In addition to their direct associations, the interaction between age and BMI was also a significant and independent determinant for hsCRP in both men ( F = 4.407, P = 0.036) and women ( F = 5.487, P = 0.019). In participants aged < 75 years, overweight (BMI ≥25.0 kg/m²) persons were more likely to have a prevalence of elevated hsCRP concentrations (≥1.00 mg/L) compared with the normal-weight (BMI 2), but such an association was not observed in those aged ≥75 years. Adiposity promotes low-grade systemic inflammation in community-dwelling persons aged <75 years.