Estimation of Metabolic Syndrome in Acanthosis Nigricans - A Hospital Based Cross-Sectional Study

Acanthosis nigricans is characterized by hyperpigmentation and velvet-like thickening of the skin. It symmetrically involves the neck, axilla, groins, antecubital and popliteal fossae, umbilical, and perianal areas. Acanthosis nigricans is a marker for insulin resistance and is increasingly found to be associated with metabolic syndrome. We conducted this study to estimate the frequency of metabolic syndrome in acanthosis nigricans.

In this hospital-based, cross-sectional study, we evaluated 60 patients with acanthosis nigricans with neck involvement. They were examined for other areas of involvement by acanthosis nigricans. Axillary and neck severity was graded based on the scale described by Burke et al. Insulin resistance was interpreted using homeostatic model assessment (HOMA-IR). Metabolic syndrome was diagnosed according to the SAM-NCEP criteria. Collected data were analyzed using IBM SPSS Statistics, Version 22 (Armonk, NY: IBM Corp).

Axilla was the most common site involved in 51 patients (85%) followed by knuckles (55%). Metabolic syndrome was found in 78.3% of our patients, and 56.66% had insulin resistance. A statistically significant association of severity grading of axillary acanthosis nigricans with both metabolic syndrome (P = 0.001) and insulin resistance (P = 0.03) was noted. However, no meaningful association was found between the severity grading of neck acanthosis nigricans with both metabolic syndrome (P = 0.4) and insulin resistance (P = 0.08). The association of neck texture grading of acanthosis nigricans with insulin resistance was statistically significant (P = 0.005).

Metabolic syndrome was seen in 78.3% of acanthosis nigricans. Axillary severity grading was associated with metabolic syndrome.