2346: Back in Action: Six Months of Biological Therapy Improve Sexual Function in Men with Ankylosing Spondylitis

Background/Purpose: Ankylosing spondylitis (AS) significantly impacts quality of life across multiple domains. To date, no studies have evaluated the impact of initial biological therapy on sexual function, despite its critical role in overall quality of life.
We aimed to evaluate the impact of initial biologic/targeted synthetic disease modifying anti-rheumatic drug (b/tsDMARD) therapy on sexual function in men with AS.

Methods: Men with AS initiating b/tsDMARD therapy within the Czech ATTRA registry completed the International Index of Erectile Function (IIEF; higher score represents better function) at baseline (M0) and after six months (M6). Routine clinical and laboratory data was collected, with patient-reported outcomes regarding function and quality of life (Health Assessment Questionnaire (HAQ), 36-Item Short Form Health Survey (SF-36), EuroQoL 5-Dimension Questionnaire (EuroQoL) and Multidimensional Health Assessment Questionnaire (MDHAQ)). Comparisons were performed using the Wilcoxon test, with p-values adjusted for multiple comparisons using the Benjamini-Hochberg method. Variable selection for baseline predictors and factors associated with improvement in IIEF domains was performed using Elastic Net regression.

Results: 52 sexually active men completed the study (mean±SD age: 40±9 years; 92.3% HLA-B27 positive). 96.2% received anti‑TNF agents, 3.8% an IL‑17 inhibitor (Table 1). At M6, we observed significant reductions in inflammatory markers (ESR, CRP) and disease activity (ASDAS), as well as improvements in function and quality of life (HAQ, MDHAQ, EuroQoL, SF-36) (p< 0.05 for all). Due to the potential ceiling effect in IIEF scores, we stratified participants by baseline presence of erectile dysfunction (ED) (IIEF Erectile Function < 26, n=12). The patients with ED experienced a significant median (IQR) increase in erectile function from 17.5 (11.5-23.5) to 26.0 (23.3-28.3) (p=0.033). There were also significant improvements in the domains of sexual desire (p=0.046) and intercourse satisfaction (p=0.033) (Figure 1). In contrast, patients without ED at baseline (n=40) maintained consistently high scores.

On the level of bivariate analysis, improvements in sexual function were linked with reduced disease activity, and improvements in physical and mental health. LASSO regression identified baseline IIEF domain scores as the strongest predictors of sexual function outcomes. Weaker predictions were observed for functional status (thoracic expansion, occiput-to-wall distance, Schober test), quality of life (EuroQoL, SF-36 mental component score), comorbidities (cardiovascular disease, metabolic disease), medication use (antidepressants, NSAIDs, COX-2 inhibitors), and disease activity measures (ASDAS, CRP, ESR) (Table 2).

Conclusion: Initial biological therapy significantly improved sexual function in men with AS, with the most striking benefits observed in those with baseline erectile dysfunction. Improvements were linked to better quality of life and reduced disease activity. These findings highlight the broader benefits of b/tsDMARD therapy beyond disease control.

Supported by MHCR 023728