Acne Keloidalis Nuchae and the Metabolic Syndrome: A Population-Based Study

Background: The association between acne keloidalis nuchae (AKN) and the metabolic syndrome (MS) has been reported anecdotally. However, it is yet to be investigated in the setting of controlled studies, leaving this topic inconclusive in the current literature. Objective: The aim was to estimate the association between AKN and the MS and its components, utilizing one of the largest cohorts of patients with AKN. Methods: A retrospective, population-based, cross-sectional study was performed between 2005 and 2018. We utilized the database of Clalit Health Services, the largest public healthcare provider organization in Israel. The current study encompassed data collected from general community clinics, primary care, and referral centers, as well as from ambulatory and hospital care. Results: A total of 2677 patients with AKN and 13,190 controls were included. The prevalence of the MS was greater in patients with AKN than in control subjects (16.1% vs. 6.6%, respectively; odds ratio [OR] 2.72; 95% confidence interval [CI] 2.40–3.08; P < 0.001). Obesity demonstrated the strongest association with AKN (OR 3.00; 95% CI 2.75–3.28), followed by type 2 diabetes mellitus (OR 2.47; 95% CI 2.20–2.77), hypertension (OR 1.82; 95% CI 1.63–2.05), and dyslipidemia (OR 1.60; 95% CI 1.46–1.75). Estimates were not altered significantly after controlling for putative confounding factors. Conclusions: A strong association was observed between AKN and the MS on the one hand, and with every one of its four components on the other. Physicians treating patients with AKN should be aware of this possible comorbidity. Patients with AKN should be carefully assessed for comorbid metabolic disorders.