Differences in Demographic and Clinical Characteristics Among Subtypes of Female Pattern Hair Loss

BACKGROUND: Female pattern hair loss (FPHL) is the most common hair loss disorder in women that can be classified into three patterns, including Ludwig, Olsen, and Hamilton-Norwood subtypes. Information regarding the comparison of demographics, clinical characteristics, and associated comorbidities among subtypes of FPHL is scarce and contradictory. OBJECTIVE: To evaluate and compare the epidemiology, clinical manifestations, and comorbid conditions of FPHL subtypes and determine their associated factors. METHODS: This retrospective study included patients who were diagnosed with FPHL between January 2000 and November 2021. Participants were classified into three subtypes, namely Ludwig, Olsen, and Hamilton-Norwood, and were statistically compared. Variables significantly associated with each FPHL subtype were identified using multivariable multinomial logistic regression analysis. RESULTS: Among the 519 patients with FPHL, the Ludwig subtype was the most prevalent (51.1%), followed by the Olsen (32.9%) and Hamilton-Norwood (16%) subtypes. The Hamilton-Norwood subtype revealed significantly higher frequencies of early disease onset (61.4%), menstrual irregularity (22.9%), polycystic ovary syndrome (PCOS, 18.1%), and seborrhea (30.1%) but lower frequencies of overweight (24.1%) and type 2 diabetes mellitus (DM, 2.4%). Multivariable multinomial regression analysis demonstrated that the Hamilton-Norwood subtype was a predictor for early disease onset and PCOS compared to Ludwig (early onset: odds ratio (OR) = 2.14, 95% confidence interval (CI) = 1.39–4.22, P = 0.02; PCOS: OR = 2.02, 95% CI = 1.55–4.84, P = 0.03), and Olsen (early onset: OR = 1.89, 95% CI = 1.03–3.92, P = 0.04; PCOS: OR = 2.24, 95% CI = 1.89–5.31, P = 0.01). In contrast, the Hamilton-Norwood pattern was at decreased risk for type 2 DM compared to Ludwig (OR = 0.51, 95% CI = 0.03–0.82, P = 0.02), and Olsen (OR = 0.68, 95% CI = 0.04–0.79, P = 0.03). CONCLUSION: The Ludwig pattern was found to be the most prevalent FPHL subtype among Thai patients. Moreover, the Hamilton-Norwood subtype was associated with early disease onset and PCOS, whereas the Ludwig and Olsen subtypes were associated with type 2 DM.