Treat-to-Target Strategy Achieves High Remission Rates with Sex Differences Attenuated Under Treat-to-Target Management in Rheumatoid Arthritis: A Longitudinal Analysis From the Rheumatoid Arthritis Saudi Database (RASD)

Hani M Almoallim,1 Sami M Bahlas,2 Yasser Bawazir,3 Albadr H Hussein,4 Gamal Mahmoud Attia,5 Hanady Manasfi,6 Zain A Bafadhl,6 Raja Adib Bakhsh,7 Alhussain Mohammed Asiri,8 Ayda Rahma Ali,8 Mohammed M Alomair,8 Hanan Almalki,8 Mona Alsharaif,8 Muhammad Irfanullah Siddiqui,9 Aous S Alhazmi,10 Suzan M Attar31Department of Internal Medicine, Faculty of Medicine, Umm Al-Qura University, Makkah, Saudi Arabia; 2Department of Medicine, International Medical Center, Jeddah, Saudi Arabia; 3Department of Medicine, Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia; 4Department of Rheumatology, King Fahad Hospital, Madinah Munawara, Saudi Arabia; 5Department of Rheumatol-Ogy, Faculty of Medicine, Al-Azhar University, Cairo, Egypt; 6Department of Internal Medicine, SMC Healthcare Hospitals, Riyadh, Saudi Arabia; 7Internal Medicine Department, King Faisal Hospital, Makkah, Saudi Arabia; 8Department of Internal Medicine, Aseer Central Hospital, Abha, Saudi Arabia; 9Department of Preventive Medicine, Almualij Alamin Clinics Medical, Makkah, Saudi Arabia; 10Department of Academic and Training Affairs, Saudi German Hospital, Makkah, Saudi ArabiaCorrespondence: Hani M Almoallim, Department of Internal Medicine, Faculty of Medicine, Umm Al-Qura University, Makkah, 21955, Saudi Arabia, Email hmmoallim@uqu.edu.saPurpose: Rheumatoid arthritis (RA) affects women two–three times more frequently than men, and registries report sex-based differences in disease activity and remission. However, sex-stratified outcome data from Saudi Arabia are limited. We evaluated sex differences in disease activity, remission rates, and predictors of remission in the Rheumatoid Arthritis Saudi Database (RASD).Patients and Methods: We conducted a prospective cohort study of 647 patients with RA receiving biological or targeted synthetic DMARDs (574 female and 73 male) with at least 12 months of follow-up. Disease activity was assessed using DAS28-CRP, CDAI, FSS, and HAQ-DI across three visits. Remission was defined as DAS28-CRP < 2.6. Linear mixed-effects models examined disease activity trajectories by sex, and multivariable logistic regression identified predictors of remission at visit 3. Benjamini–Hochberg correction was applied across six Stage-4 chi-square tests and across three pairwise sex comparisons within each outcome.Results: Overall remission rates rose from 50.9% at visit 1 to 83.5% at visit 3, with no significant sex differences after correction for multiple comparisons. DAS28-CRP declined significantly over time in both sexes (p < 0.001). Males had higher adjusted CDAI at Visit 1 (13.43 vs 11.12; BH-adjusted p = 0.007), but not at visits 2 or 3; the visit-by-sex interaction was significant (unadjusted Type III p = 0.032). Fatigue and functional disability did not differ by sex. ACPA positivity was associated with higher odds of remission (OR 1.67, 95% CI 1.03– 2.68, p = 0.036), while RF positivity was associated with lower odds (OR 0.61, 95% CI 0.38– 0.96; p = 0.034). Sex was not an independent predictor.Conclusion: In this Saudi RA cohort, both sexes achieved high remission rates under treat-to-target management, and sex differences in disease activity did not persist after multiple-comparison correction. RF and ACPA, rather than sex, were the dominant predictors of remission.Keywords: rheumatoid arthritis, sex differences, remission, DAS28-CRP, ACPA, rheumatoid factor, Saudi Arabia