Liu ZS, Tang H, Zhang HM, Bai XY, Yang H, Li XF, Qian JM. Sex-specific differences in the efficacy and prognosis of 5-aminosalicylic acid therapy for ulcerative colitis: A 20-year retrospective cohort study. World J Gastroenterol 2026; 32(22): 118036 [DOI: 10.3748/wjg.v32.i22.118036]
Corresponding Author of This Article
Jia-Ming Qian, MD, Professor, Department of Gastroenterology, Peking Union Medical College Hospital, No. 1 Shuaifuyuan, Dongcheng District, Beijing 100730, China. qianjm@pumch.cn
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Gastroenterology & Hepatology
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Liu ZS, Tang H, Zhang HM, Bai XY, Yang H, Li XF, Qian JM. Sex-specific differences in the efficacy and prognosis of 5-aminosalicylic acid therapy for ulcerative colitis: A 20-year retrospective cohort study. World J Gastroenterol 2026; 32(22): 118036 [DOI: 10.3748/wjg.v32.i22.118036]
Zhao-Shi Liu, Xiao-Feng Li, Department of Gastroenterology, The Fifth Affiliated Hospital of Sun Yat-sen University, Zhuhai 519000, Guangdong Province, China
Zhao-Shi Liu, Hao Tang, Xiao-Yin Bai, Hong Yang, Jia-Ming Qian, Department of Gastroenterology, Peking Union Medical College Hospital, Beijing 100730, China
Hui-Min Zhang, Department of Gastroenterology, Henan Provincial People’s Hospital, Zhengzhou University People’s Hospital, Zhengzhou 450003, Henan Province, China
Author contributions: Liu ZS wrote the original draft; Liu ZS, Tang H, and Qian JM designed the study; Liu ZS, Tang H, and Zhang HM were responsible for developing the methodology; Liu ZS, Zhang HM, Bai XY, and Li XF collected and analyzed data; Liu ZS, Tang H, and Bai XY performed statistical analysis; Yang H, and Qian JM participated in the review and editing; all authors approved the final version.
Supported by the Health Research and Special Projects Grant of China, No. 201002020; and CAMS Innovation Fund for Medical Sciences, No. 2016-I2M-3-001.
Institutional review board statement: This study was approved by the Institutional Ethics Committee of Peking Union Medical College Hospital (Ethics approval No. S-K1889).
Informed consent statement: Written informed consent for participation was not required for this study in accordance with the national legislation and the institutional requirements.
Conflict-of-interest statement: The authors declare that they have no conflict of interest.
STROBE statement: The authors have read the STROBE Statement—a checklist of items, and the manuscript was prepared and revised according to the STROBE Statement-a checklist of items.
Data sharing statement: The original contributions presented in the study are included in the article/Supplementary material, further inquiries can be directed to the corresponding author.
Corresponding author: Jia-Ming Qian, MD, Professor, Department of Gastroenterology, Peking Union Medical College Hospital, No. 1 Shuaifuyuan, Dongcheng District, Beijing 100730, China. qianjm@pumch.cn
Received: December 26, 2025 Revised: February 13, 2026 Accepted: March 9, 2026 Published online: June 14, 2026 Processing time: 156 Days and 11.1 Hours
Abstract
BACKGROUND
Despite 5-aminosalicylic acid (5-ASA) being the first-line therapy for ulcerative colitis (UC), there is limited real-world evidence concerning sex-specific differences in the efficacy of 5-ASA therapy and patient prognosis.
AIM
To investigate sex-disparities in 5-ASA treatment responses and long-term outcomes in a Chinese large-scale UC cohort.
METHODS
A retrospective study was conducted on 554 consecutive UC patients treated with 5-ASA at Peking Union Medical College Hospital between January 2003 and June 2023. The rates of endoscopic mucosal healing (EMH) and colectomy were compared between the female and male cohorts, and 1:1 propensity score matching (PSM) was performed for demographics, comorbid conditions and drugs, disease conditions, laboratory parameters, and UC medication use. Cox regression analysis and Kaplan-Meier curves were constructed for survival analyses.
RESULTS
There were 243 patients in the female cohort (mean age, 34.8 ± 11.3 years; 21.4% with ulcerative proctitis) and 311 patients in the male cohort (mean age, 36.2 ± 13.5 years; 22.8% with ulcerative proctitis). After PSM, there was a higher risk of UC flare-up in the male vs female cohort [adjusted odds ratio = 2.78, 95% confidence interval (CI): 1.69-4.55, P < 0.001]. Male sex was an independent protective factor against EMH [adjusted hazard ratio (aHR) = 0.89, 95%CI: 0.87-0.91, P = 0.03] and a risk factor for colectomy (aHR = 1.93, 95%CI: 1.13-3.29, P = 0.02). Male patients had longer EMH-free survival (aHR = 0.63, 95%CI: 0.39-1.00, P = 0.048) and shorter colectomy-free survival (aHR = 1.80, 95%CI: 1.06-3.05, P = 0.027).
CONCLUSION
Pronounced sex-specific differences exist in 5-ASA therapy efficacy and patient prognosis. Male sex is associated with more frequent relapses, a lower likelihood of EMH, and a higher risk of colectomy.
Core Tip: Real-world data concerning sex-specific differences in the response to and long-term outcomes of 5-aminosalicylic acid (5-ASA) therapy for ulcerative colitis (UC) in large-scale UC cohorts are lacking. This retrospective study analyzed 354 patients receiving 5-ASA treatment after 1:1 propensity score matching. Male patients had an increased chance of frequent UC flare-ups, less frequent and delayed endoscopic mucosal healing, and a higher risk of surgery. These findings emphasize the need for sex-adapted therapeutic strategies to optimize 5-ASA utilization and improve individualized UC management.
Citation: Liu ZS, Tang H, Zhang HM, Bai XY, Yang H, Li XF, Qian JM. Sex-specific differences in the efficacy and prognosis of 5-aminosalicylic acid therapy for ulcerative colitis: A 20-year retrospective cohort study. World J Gastroenterol 2026; 32(22): 118036
The global burden of ulcerative colitis (UC) has increased dramatically over recent decades, with a worldwide prevalence ranging from 0.3% to 0.5%, and with females accounting for approximately 48.2% of cases[1]. In China, UC has undergone an epidemiological transition[2]: The incidence showed a rapid increase driven by urbanization, westernization of diets, and improved diagnostic capabilities. This rising prevalence has led to substantial healthcare expenditure, indicating an urgent need for cost-effective and optimized treatment strategies.
Despite the rapid development of advanced therapies (e.g., biologics and small-molecule drugs) for UC, 5-aminosalicylic acid (5-ASA) remains the first-line medication for mild-to-moderate UC and an adjuvant drug for severely active UC[3]. Its safety and efficacy have been fully validated across disease severities, particularly in inducing clinical remission, promoting mucosal healing, and reducing relapse rates[4-7]. However, not all patients benefit from initial or long-term use of 5-ASA[8]. This inter-patient variability emphasizes the critical need to identify predictive factors for stratifying patients based on their likelihood of response and guiding personalized care. A notable yet understudied contributor to this variability is biological sex. Regrettably, sex-stratified analyses are conspicuously absent in most clinical studies on 5-ASA. Only 23% of historical clinical studies have reported 5-ASA treatment outcomes specifically in female UC patients[4]. As 5-ASA is the cornerstone of UC treatment, clinical guidelines from different regions advocate for its routine use[3-5,9]. However, current clinical recommendations for 5-ASA only incorporate optimizations based on disease activity and lesion location, lacking sex-specific strategies[4,9]. This “one-size-fits-all” research paradigm has created a gap in clinical practice, resulting in the predominance of uniform “sex-agnostic” dosing and monitoring strategies[10].
To address this gap, we conducted a retrospective analysis of UC patients treated with 5-ASA at a tertiary referral center in China. The primary aim of this study was to explore distinct patterns of patient response to 5-ASA based on biological sex, with the goal of optimizing the benefit-risk ratio of 5-ASA therapy.
MATERIALS AND METHODS
Patient selection and data collection
Consecutive inpatients and outpatients diagnosed with UC at Peking Union Medical College Hospital between January 2003 and June 2023 were enrolled in this study. The study enrolment flowchart is shown in Figure 1.
Figure 1 Flowchart of cohort screening and enrollment.
5-ASA: 5-aminosalicylic acid; UC: Ulcerative colitis.
The inclusion criteria were as follows: (1) Aged 18-75 years and diagnosed with UC according to a comprehensive assessment combining medical history, laboratory tests, imaging findings, endoscopic observations, and pathological results[4]; and (2) Initial treatment with oral 5-ASA after UC diagnosis.
The exclusion criteria were: (1) Diagnosed with tumors before UC diagnosis; (2) Missing details about endoscopic examination, use of medications, and surgery; (3) Previous autoimmune diseases and receiving corticosteroids, immunomodulators, or biologics prior to UC diagnosis, or 5-ASA prescriptions; (4) Follow-up duration < 1 year; and (5) Primary diagnosis changed from UC to other disease, or loss to follow-up.
Demographic characteristics [biological sex, age at disease onset, body mass index (BMI) at diagnosis, and smoking status] and treatment details (oral 5-ASA regimen and use of 5-ASA enemas or suppositories) were systematically collected. Disease activity at onset was stratified as mild to moderate or severe according to the Mayo clinic disease activity index (DAI) score[11], while the severity of intestinal lesions was classified per the Montreal classification[12]. Detailed data on extraintestinal manifestations, comorbidities, severe UC-related complications, laboratory indices, endoscopic reports, medical or surgical interventions, and the occurrence of malignancy during follow-up were meticulously documented.
The primary endpoint was the earliest occurrence of primary outcome events, malignancy, loss to follow-up, or the last follow-up date (June 30, 2023). Follow-up involved the review of updated medical records via the hospital information system or telephone interviews. This study was approved by the Institutional Ethics Committee of Peking Union Medical College Hospital (Ethics approval No. S-K1889).
Definitions and outcomes
The types of oral 5-ASA included mesalazine (brand names: Pentasa; Salofalk; and Etiasa) and balsalazide. UC flare-up was defined as the occurrence of gastrointestinal symptoms after a period of remission. Endoscopic mucosal remission (EMR) was defined as a Mayo endoscopic score (MES) ≤ 1[3], and endoscopic mucosal healing (EMH) as a MES of 0[1]. Advanced therapy was defined as simultaneously using or subsequent addition of systemic steroid, immunosuppressants, or biologics on prescription of 5-ASA. Colectomy was defined as gastrointestinal resection or ostomy performed for UC-related indications, including refractory disease or life-threatening complications. Severe complications were defined as conditions diagnosed after the initial confirmation of UC, including intestinal perforation, intestinal obstruction, massive gastrointestinal hemorrhage, toxic megacolon, abdominal infection, septic shock, and colorectal cancer (CRC). Primary outcomes included EMH and colectomy. Secondary outcomes included the frequency of UC flare-up per year, and the occurrence of EMR and severe complications. For survival analyses, the follow-up time was defined as the interval between oral 5-ASA therapy initiation and the first occurrence of a predefined endpoint event.
Statistical analysis
All statistical analyses were conducted using SPSS software (version 26.0, SPSS Inc., Chicago, IL, United States). Baseline characteristics of cohorts were described using means, standard deviations, and proportions. Covariates (demographics, comorbid diseases, disease condition at onset, laboratory parameters, accompanying medication, 5-ASA regimen, and UC medication use) were identified. Propensity score matching (PSM) (1:1) was performed to balance the following covariates between groups: Follow-up period, age, disease duration, smoking status, BMI, diabetes mellitus, hypertension, opportunistic infections, DAI at onset, disease extent, and accompanying medications. PSM was also performed based on C-reactive protein and other UC medication use. Logistic regression analysis of the identified covariates was conducted using SPSS to obtain propensity scores for all individuals. The propensity scores were used to match patients using greedy nearest-neighbor algorithms, with a caliper width of 0.1 pooled standard deviations. The standardized mean difference after PSM indicates whether a covariate has been matched successfully between female and male cohorts. A standardized mean difference < 0.1 indicates that the difference between cohorts is small. After PSM, the risk of each outcome was calculated and expressed as the adjusted odds ratio (aOR), with 95% confidence intervals (CIs). Cox proportional hazards regression analyses were performed to assess covariates (selected based on prior published evidence and our institutional clinical experience) potentially associated with the primary outcomes, to mitigate any confounding effects of these variables on sex-specific outcome estimates. Kaplan-Meier curves for cumulative EMH survival and colectomy-free survival were generated, with log-rank tests used for basaloid group comparisons after 1:1 PSM. Statistical significance was defined as P < 0.05.
RESULTS
Characteristics of study cohort
A total of 554 patients were recruited, including 243 females and 311 males (Table 1). There was no difference in the mean follow-up period (P = 0.37) or disease duration (P = 0.36) between the female and male cohorts. During the follow-up period, 84 patients (110 person times) presented with extraintestinal manifestations (mainly joint and skin manifestations; Supplementary Table 1). Thirty-six patients developed malignancies, including 13 (2.3%) with CRC and 23 (4.2%) with extra-colorectal malignancies, before PSM. As shown in Supplementary Table 2, before PSM, male patients had a higher rate of CRC than female patients (11 patients vs 2 patients, P = 0.03), but there was no significant difference between the two cohorts after PSM. Additionally, males had significantly higher rates of smoking (40.5% vs 1.6%, P < 0.001) and overweight (BMI ≥ 24 kg/m2; 58.8% vs 40.3%, P < 0.001).
Table 1 Baseline characteristics of female and male ulcerative colitis patients receiving 5-aminosalicylic acid treatment before and after propensity score matching, mean ± SD/n (%).
As displayed in Table 2, 44.0% and 47.7% of females and males, respectively, with 5-ASA prescriptions experienced severe activity at onset. In the female cohort, 42.8% had ulcerative pancolitis, and 21.4% had ulcerative proctitis, vs 52.7% and 22.8% in the male cohort, respectively. However, no significant difference was observed in 5-ASA regimens between the sexes. In total, 77.4% and 72.0% of females and males had systemic steroid use, respectively. In the female cohort, 39.1% and 21.0% of patients had immunomodulators and biologics use, and in the male cohort the proportions were 32.8% and 15.1%, respectively. A complete list of demographic parameters, conditions at onset, comorbid conditions, laboratory parameters, and data on treatment before and after PSM is shown in Table 1.
Table 2 Comparison of 5-aminosalicylic acid therapy outcomes between the female and male cohorts after 1:1 propensity score matching, n (%).
Sex differences in 5-ASA treatment response and outcomes
We compared efficacy and prognosis outcomes between the male and female cohorts after PSM, and the results are summarized in Table 2. The data showed that 37.9% of male patients had UC flare-ups more than twice per year, while the proportion of female patients was only 18.1%. Additionally, males exhibited a significantly higher risk of frequent UC relapse than females (aOR = 2.78, 95%CI: 1.69-4.55). There were 60 patients (16.9%) with serious UC-related complications and 23 (6.5%) with malignancies. However, there was no difference in the risk of serious complications (aOR = 1.50, 95%CI: 0.85-2.63) or malignancies (aOR = 1.60, 95%CI: 0.68-3.81) between the two cohorts. Although there was no significant difference in the risk of EMR between the two cohorts, there was a lower chance of EMH in the male cohort (aOR = 0.58, 95%CI: 0.34-0.97). Notably, there was a higher risk of surgical intervention in the male cohort than in the female cohort (aOR = 1.86, 95%CI: 1.05-3.31).
Survival analysis of primary outcomes
As detailed in Table 2, 72 (20.3%) patients achieved EMH, while 59 (16.7%) underwent colectomy after PSM. Male patients had a lower rate of EMH (16.4% vs 25.4%) and a higher rate of colectomy (20.9% vs 12.4%) than female patients. Cox proportional hazards regression (Table 3) demonstrated that male sex was an independent protective factor against EMH [adjusted hazard ratio (aHR) = 0.89, 95%CI: 0.87-0.91, P < 0.001], and an independent risk factor for colectomy (aHR = 1.93, 95%CI: 1.13-3.29, P = 0.02). Sex-stratified Kaplan-Meier survival analysis indicated that male patients achieved EMH significantly later than female patients (aHR = 0.63, 95%CI: 0.39-1.00, P = 0.048) (Figure 2A). Male patients had a significantly shorter colectomy-free survival than female patients (aHR = 1.80, 95%CI: 1.06-3.05, P = 0.027), indicating a lower and delayed risk of colectomy in females (Figure 2B).
Figure 2 Kaplan-Meier curves.
A: Kaplan-Meier cumulative survival curves for endoscopic mucosal healing: Comparison between the female and male cohorts after 1:1 propensity score matching; B: Kaplan-Meier colectomy-free survival curves: Comparison between the female and male cohorts after 1:1 propensity score matching. aHR: Adjusted hazard ratio; EMH: Endoscopic mucosal healing; CI: Confidence interval.
Table 3 Univariate and multivariate Cox regression analysis of endoscopic mucosal healing and colectomy in ulcerative colitis patients receiving 5-aminosalicylic acid treatment after 1:1 propensity score matching.
To prevent bias associated with the DAI at onset, the efficacy and prognosis of 5-ASA therapy in mild-to-moderate-activity UC patients were analyzed separately. The baseline characteristics of the cohorts before and after PSM are displayed in Supplementary Table 3. Although there was no significant difference in the risk of UC flare-ups between the two cohorts (aOR = 1.58, 95%CI: 0.90-2.78), the risk of EMH (aOR = 0.49, 95%CI: 0.27-0.91) was lower in males than in females, whereas the risks of serious complications (aOR = 2.56, 95%CI: 1.21-5.40) and colectomy (aOR = 3.51, 95%CI: 1.42-8.66) were higher in males (Supplementary Table 4). The survival analysis was consistent with previous findings, indicating that male sex is associated with a lower rate of delayed EMH (aHR = 0.57, 95%CI: 0.34-0.95, P = 0.03), as well as a higher risk of earlier colectomy (aHR = 3.13, 95%CI: 1.33-7.37, P = 0.006) (Supplementary Figures 1 and 2, Supplementary Table 5).
DISCUSSION
In this long-term cohort study of Chinese UC patients, we identified distinct sex-specific responses to and long-term outcomes of 5-ASA therapy. Male sex elevated the risk of frequent UC flare-ups and was an independent protective factor against EMH and a risk factor for colectomy. Compared with females, males achieved EMH later and underwent colectomy earlier. Collectively, these results demonstrate the critical role of biological sex in modulating 5-ASA treatment outcomes and open the way for optimized “sex-adapted” therapeutic strategies in UC management.
UC is a gastrointestinal disease characterized by relapse and alternating periods of remission. There is a correlation between UC relapse and treatment response, and disease activity tends to decrease over time[13]. The severity of UC flare-ups and their response to treatment vary and are difficult to predict, ranging from local symptoms to life-threatening flares that requires colectomy[13]. Previous studies have found a strong interaction between sex and recurrence frequency. Contrary to our findings, one study reported that a greater number of prior relapses was associated with a shorter time to relapse in female, but not in male patients[14]. In the present study, 37.9% of male patients had UC flare-ups more than twice per year, with an increased risk of disease activity vs females (18.1%), indicating poorer symptomatic relief with 5-ASA treatment in males. After adjusting for various confounding factors that may affect disease activity, correlations of relapse with 5-ASA treatment and sex were found.
Historically, symptomatic relief was the primary therapeutic target in patients with UC because of the lack of an appropriate endoscopic technique. With the development of endoscopic technology, clinical remission has become a short-to-intermediate-term endpoint, and a necessary but insufficient treatment target[1]. EMH was treated as an important long-term endpoint in UC by the International Organization for the Study of Inflammatory Bowel Diseases in the Selecting Therapeutic Targets in inflammatory bowel disease II consensus guidelines[15]. EMH represents not only a core therapeutic goal for UC during remission induction but also a robust prognostic indicator for favorable long-term outcomes. After adjusting for disease activity, disease extent, and other UC medications, we found that male sex was associated with a decreased likelihood of, and delayed, EMH, though there was no significant difference in the rate of EMR between the two cohorts. Complete mucosal healing, defined as a MES of 0, has superior prognostic value compared with partial mucosal improvement (MES = 1), including reduced hospitalization rates and lower disease relapse risk[16-20]. Relief of UC symptoms is usually related to mucosal healing, and the risk of subsequent colectomy was significantly reduced compared to those without mucosal healing[21]. These results are consistent with the finding that male patients experienced poorer 5-ASA therapy efficacy and prognosis than female patients. Notably, consistent with the overall cohort, our subgroup analyses of patients with mild-to-moderate UC (Supplementary Figure 1, Supplementary Tables 3-5) reproduced these findings: Female sex remained associated with earlier and higher rates of EMH, confirming the robustness of the biological sex disparity in mucosal healing across disease activity strata.
The role of biological sex in the long-term efficacy of 5-ASA is currently poorly understood, and knowledge of its potential mechanisms is lacking. Male sex was identified as a negative predictor of EMH in our study, consistent with previous evidence supporting estrogen-mediated intestinal mucosal protection[22-24]. Critically, cotreatment with an estrogen receptor β-selective agonist synergistically enhanced the mucosal healing efficacy of 5-ASA. Intriguingly, a recent metagenomic study identified gut microbial acetyltransferase genes as key factors elevating the risk of 5-ASA treatment failure[8]. Given that 5-ASA is predominantly absorbed across the colonic mucosa, sex-specific disparities in colonic drug absorption kinetics may also influence its therapeutic efficacy[25]. Consistent with our findings and multiple independent investigations, male UC patients typically present with more extensive colonic lesion involvement. This phenotype can lead to uneven 5-ASA concentrations and reduced mucosal absorption efficiency, and consequently impaired anti-inflammatory activity and mucosal healing capacity in response to 5-ASA. These findings emphasize the clinical imperative of avoiding premature discontinuation of 5-ASA therapy in female UC patients to preserve the mucosal healing benefit. For male patients, using 5-ASA as an induction and long-term maintenance medication to achieve EMH requires a more cautious attitude.
Earlier studies typically reported cumulative probabilities of colectomy of about 20%-30% after 25 years, with rates being higher in studies involving referral centers[13]. Despite the availability of more advanced therapies in clinical practice, the drug failure rate in UC remains high. Over 10% of patients with a disease course > 10 years ultimately require surgery[26]. Due to the long study period of 20 years, our colectomy rate was 16.7% (Table 2), and even in the mild-to-moderate-UC patients, the rate of colectomy was still 13.5% (Supplementary Table 4).
Another important result was that male UC patients receiving 5-ASA treatment had a greater chance of colectomy than female patients. Male sex was an independent risk factor for colectomy, consistent with prior research suggesting poorer long-term clinical outcomes in male UC patients[27-31]. Given our supplemental analysis results, this conclusion also applies to the mild-to-moderate-activity cohorts (Supplementary Figure 2 and Supplementary Table 4). Several factors may contribute to this disparity. First, male patients had a higher prevalence of pancolitis, a disease phenotype well established as a strong predictor of severe disease progression and colectomy in UC[32]. Second, our male subgroup had higher rates of smoking, overweight, and comorbid hypertension, which are consistently associated with increased disease severity, treatment resistance, and severe complications[33-37]. Although disease severity and factors such as smoking were adjusted for through PSM, residual confounding may still exist, and bias cannot be ruled out. Third, unlike females, males lack estrogen-mediated intestinal mucosa-protective signaling pathways, leading to delayed mucosal repair and poor long-term prognosis[22-24]. Additionally, non-biological factors including healthcare-seeking behavior, sex-related social roles, clinician treatment bias, and patient-specific preferences and concerns exert a notable influence on surgical decision-making[38]. Female patients are often less willing to undergo colectomy due to heightened concerns regarding perioperative risks, potential impacts on fertility, and postsurgical body image changes[39,40].
This study possesses several notable strengths that enhance the credibility and clinical relevance of its findings. First, it involved a large, longterm, singlecenter retrospective cohort with detailed clinical, endoscopic, and pathological documentation, enabling robust assessment of the long-term response to and prognosis of 5-ASA therapy. Second, rigorous adjustment was conducted, including by PSM, for baseline imbalances in disease severity, comorbidities, and concomitant therapy, strengthening the credibility of causal inferences regarding sex-specific outcomes. Finally, validation of the key findings in the mild-to-moderate-UC subgroups (Supplementary Figures 1 and 2, Supplementary Tables 3-5) confirms the consistency of sex disparities in mucosal healing and prognosis across clinically relevant disease activity levels.
Several limitations of this study should also be acknowledged. First, as a retrospective observational study, residual confounding from uncollected variables (e.g., longitudinal medication dose changes, specific adverse events, and dietary factors) cannot be fully excluded. Second, due to temporal and clinical practice limitations, some severe UC patients were included in the cohort. Though selective bias was avoided, such that the results truly reflect the current application status of 5-ASA in UC patients differing in disease severity, confounding nevertheless may impact the generalizability of the results. Third, selection bias (given the single-tertiary-center design) means that the results may not fully generalize to UC patients diagnosed in community settings.
CONCLUSION
In this study, male sex was associated with poorer efficacy of 5-ASA therapy and prognosis in UC patients, suggesting a latent mechanism of 5-ASA related to biological sex. These results demonstrated that incorporating sex stratification into UC clinical trials and guidelines is essential for advancing precision medicine in UC management. In male cohort, early aggressive treatment and targeted management of modifiable risk factors are crucial for 5-ASA treatment response and long-term outcomes. Prospective and mechanistic research is needed to validate these findings.
ACKNOWLEDGEMENTS
We express our appreciation to all patients with UC for their collaboration in the current study.
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Lopes EW, Chan SSM, Song M, Ludvigsson JF, Håkansson N, Lochhead P, Clark A, Burke KE, Ananthakrishnan AN, Cross AJ, Palli D, Bergmann MM, Richter JM, Chan AT, Olén O, Wolk A, Khalili H; EPIC-IBD investigators. Lifestyle factors for the prevention of inflammatory bowel disease.Gut. 2022;gutjnl-2022.
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Creativity or innovation: Grade A, Grade B, Grade B, Grade C
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P-Reviewer: Dang LM, MD, Lecturer, Viet Nam; Elsayed MOK, MD, Professor, United Kingdom; You LW, PhD, China S-Editor: Fan M L-Editor: A P-Editor: Yu HG
