Adipocytokine and Inflammatory Profile in Asian Indian Type 2 Diabetes Mellitus: A Case-Control Study

Abstract

Chronic low-grade inflammation and adipose tissue dysfunction are both implicated in the pathogenesis of type 2 diabetes mellitus (T2DM), though adipocytokine and inflammatory marker profiles appear to vary across populations. This hospital-based case-control study compared circulating adiponectin, leptin, interleukin-6 (IL-6), tumour necrosis factor-alpha (TNF-?), C-peptide, and high-sensitivity C-reactive protein (hsCRP) between 40 Asian Indian patients with T2DM and 40 non-diabetic controls, nested within a cohort recruited for femur bone surgery. Adiponectin, leptin, IL-6, TNF-?, and hsCRP were measured by ELISA; C-peptide was measured separately by chemiluminescent immunoassay. None of the six markers differed significantly between groups (all p>0.05). A post-hoc power analysis showed that observed effect sizes for adiponectin, leptin, TNF-?, C-peptide, and hsCRP were small (Cohen's d = 0.05–0.20), suggesting that any true between-group differences for these markers are likely to be small rather than simply undetected. IL-6 showed a larger observed effect (d = 0.44) that the study had only 49% power to detect, leaving that result inconclusive rather than negative. Adiponectin, leptin, TNF-?, C-peptide, and hsCRP are unlikely to discriminate T2DM from non-diabetic status in this population; IL-6 remains a candidate marker warranting a larger, adequately powered study. Keywords: Adipocytokines; Asian Indians; C-peptide; Inflammation; Interleukin-6; Type 2 diabetes mellitus