A study of body mass index, waist circumference, body fat percentage, blood sugar levels, and lipid profile in patients of facial acanthosis Nigricans

Introduction: Facial acanthosis nigricans (FAN) is a term used synonymously and interchangeably with metabolic melanosis and metabolic melasma. FAN is described as brown-to-black macular pigmentation with blurred ill-defined margins, commonly found on the forehead and zygomatic and malar areas with varying degrees of textural changes ranging from mild roughness to frank verrucous appearance of the affected areas. Aims and Objective: (i) The aims and objectives were to study the clinical patterns of FAN; (ii) to determine the prevalence of obesity, dyslipidemia, and blood sugar levels in patients of FAN; and (iii) to determine the association of body fat percentage (BFP) with sex, body mass index (BMI), serum triglycerides, and waist circumference (WC). Materials and Methods: This was a prospective descriptive study. One-hundred patients of FAN were included in the study that carried out over a period of 1 year. The BMI and WC of the included patients were used as parameters of obesity. BFP, lipid profile, and blood sugar levels were measured. Data were also obtained on the basis of history and clinical examination. Results: The patterns of facial pigmentation seen included the forehead and zygomatic (43%), zygomatic and malar (16%), involving the forehead (32%), and diffuse darkening of the face (9%). Overall periorbital and perioral darkening were seen in 22% of the patients, while acanthosis nigricans of other sites was found in 65% of the patients. Eighty-eight patients (88%) reported exposure to sunlight of >2 h. Twenty-one percentage of patients were overweight and 61% obese on basis of the BMI, WC was high in 62% of the patients, and BFP was high in 74% of the patients. High-density lipoprotein (HDL) levels were low in 50% of the cases, while hypertriglyceridemia was found in 38% of the cases. However, no derangement of blood sugar levels was found in any patient. A significant statistical association was found between high BFP with male sex (P = 0.004), high BMI (P = 0.0002), high WC (P < 0.001), and low serum HDL levels (P = 0.039). Conclusion: We document an increased prevalence of obesity, deranged lipid profile, and high BFP in patients presenting with FAN, and it should be considered a cutaneous marker of obesity. Furthermore, a simple tool such as BFP can be used to screen patients of FAN for obesity.