Acanthosis nigricans is a skin condition characterized by areas of dark, velvety discoloration in body folds and creases. The affected skin can become thickened. Most often, acanthosis nigricans affects your armpits, groin and neck.
Acanthosis nigricans is not contagious. It is not harmful. Sometimes, it is a warning sign of a health problem that requires medical attention Most people who have acanthosis nigricans have also become resistant to insulin. Insulin is a hormone secreted by the pancreas that allows your body to process sugar. Insulin resistance is what eventually causes type 2 diabetes.
The prevalence of Acanthosis nigricans in Japan was estimated to be about metabolic syndrome and type 2 diabetes mellitus were 17.4%, 34.8% and 19.6%, respectively. There was a strong association between AN and metabolic syndrome. The sensitivity, specificity, positive predictive value and negative predictive value of AN to detect metabolic syndrome were 28.2%, 89.0%, 45.9% and 79.0% for males, and 29.2%, 88.4%, 65.6% and 62.3% for females, respectively.