Alopecia Areata Is Associated with an Increased Risk for Prediabetes and Obesity: A Nationwide Case—Control Study

Background and Aims: Alopecia areata (AA) is a non-scarring inflammatory hair loss condition associated with various immune-mediated comorbidities. Prediabetes, characterized by elevated blood glucose levels not yet high enough to be classified as diabetes, significantly increases the risk of developing type 2 diabetes mellitus (T2DM) and cardiovascular complications. The associations between AA obesity and prediabetes have long been investigated in an attempt to identify preventable risk factors, yet the literature is relatively scarce and inconclusive. This study aimed to explore the association between AA, prediabetes, obesity, and T2DM in a large population cohort. Methods: All patients diagnosed with AA between 2005 and 2019 within Maccabi Healthcare Services (MHS) in Israel were compared with age-matched and gender-matched healthy controls for prediabetes, T2DM and obesity, using logistic regression models for all analyses. A total of 33,401 patients with AA and 66,802 controls were included in the analysis. Results: The prevalence of prediabetes was significantly higher in AA patients (26.3%) compared to controls (18.1%), with an odds ratio (OR) of 1.62. Obesity prevalence was also higher in AA patients (17.2% vs. 13.3%, OR 1.35). T2DM prevalence was similar between groups. Prediabetes prevalence notably increased with age in AA patients, especially in those aged 40 and older (OR 2.02). Discussion: The study highlights a significant association between prediabetes and alopecia areata, with prediabetes risk emerging prominently in AA patients. Obesity also showed a strong link with AA. These findings suggest the need for regular screening and early management of prediabetes and obesity in patients with AA to potentially mitigate associated health risks.