The Role of Sex in Body Composition Differences in Hidradenitis Suppurativa: Insights from Bioelectrical Impedance Analysis

<b>Background</b>: Hidradenitis suppurativa (HS) is a rare, debilitating, chronic inflammatory skin disease. This study aimed to investigate differences in body composition between patients with hidradenitis suppurativa (HS) and healthy controls, with a particular focus on sex-specific disparities, while also exploring secondary associations with muscle health and quality of life. <b>Methods</b>: Body composition was measured using a bioanalyzer and compared between HS individuals (<i>n</i> = 53) and controls (<i>n</i> = 50). <b>Results:</b> The mean BMI was significantly higher in the HS group than in the controls (median 29.6 vs. median 22.1; <i>p</i> < 0.001, effect size -0.581). The patients with HS had a significantly higher fat mass (mean 26.2 ± 22.7 vs. 16.3 ± 6.0; <i>p</i> < 0.001, effect size -0.400), level of visceral fat (median 9 vs. 2; <i>p</i> < 0.001, effect size -0.473), percentage of total body water (mean 45.9 ± 12.3 vs. 31.9 ± 14.3; <i>p</i> < 0.001, effect size -0.508), skeletal muscle index (median 8.9 vs. 7.3; <i>p</i> < 0.001, effect size -0.445), and bone mass (median 3.2 vs. 2.5; <i>p</i> < 0.001, effect size -0.421); at the same time, they had a significantly lower predicted muscle mass (median 19.8 vs. 47.3; <i>p</i> < 0.001, effect size -0.740) and percentage of skeletal muscle mass (mean 38.2 ± 7.8 vs. 42.3 ± 5.5; <i>p</i> = 0.008, effect size -0.263) in comparison to the controls. The HS group was also characterized by a higher metabolic age (median 65 vs. 21 years; <i>p</i> < 0.001, effect size -0.760) and basal metabolic rate (median 1927 vs. 1489 kcal; <i>p</i> < 0.001, effect size -0.444). <b>Conclusions</b>: Patients with HS exhibit a distinctive pattern in body composition parameters when compared to healthy controls, which may hold significant potential for enhancing diagnostic accuracy and monitoring disease progression. This study highlighted sex-specific differences in body composition, emphasizing the need to consider biological sex in the pathophysiology and clinical evaluation of HS. Further research is needed to explore the clinical utility of body composition analysis in disease progression, therapeutic response, and personalized management.