Clinical Features, Investigative Profile and Association with Metabolic Syndrome in Facial Acanthosis Nigricans: A Case–Control Study in Indian Patients

Abstract

Objectives: The present study was undertaken to study the clinical profile and laboratory abnormalities in patients with facial acanthosis nigricans (FANs). The significance of FAN as a marker of insulin resistance (IR), metabolic syndrome (MS) and its components was determined by comparing with controls without FAN. Materials and Methods: Fifty clinically diagnosed cases of FAN of all ages and both sexes were enrolled. Age- and sex-matched obese patients without FAN were included as controls. Waist circumference, blood pressure and body mass index were measured. Venous samples were taken from all patients and controls for measuring fasting glucose level, fasting insulin levels and fasting lipid profile. Statistical analysis was done using the Chi-square test and unpaired t-test. Results: The prevalence of hypertension, dysglycaemia, hyperlipidaemia, elevated Homeostatic Model Assessment for IR (HOMA-IR) and MS was significantly higher in cases of FAN than controls (P < 0.05). The mean levels of fasting blood sugar, HOMA-IR, hypertension, high-density lipoprotein and serum triglycerides were significantly higher in patients of FAN than controls (P < 0.05). The odds ratio for FAN cases developing MS was determined to be 5.31. Conclusion: FAN may be considered as a significant clinical marker of IR with increased risk for MS and its component when compared to controls. All patients with FAN should be considered for a thorough biochemical workup to rule out MS. In all detected cases, it is prudent to initiate prompt remedial measures including lifestyle changes and pharmacotherapy to prevent long-term morbidity and mortality.