Temporal trend of disease recognition, treatment paradigm, and clinical outcomes of Crohn disease in Thailand from 2000 through 2017: Is early use of thiopurines beneficial?

Comparison of 1-Year Clinical Course in Patients With Newly Diagnosed Inflammatory Bowel Disease Between Vietnam and Korea: A Multinational, Multicenter Retrospective Cohort Study

Background/Aims

The differences in the clinical course of Crohn's disease (CD) and ulcerative colitis (UC) among Asian countries remain unknown. Thus, we compared the clinical characteristics, treatment, and one-year outcomes of newly diagnosed inflammatory bowel disease (IBD) patients between Vietnam and Korea.

Methods

A retrospective cohort study was conducted at seven tertiary hospitals in these countries between January 2020 and January 2021. Data on demographics, diseases, treatment, and outcomes during 1 year after diagnosis were collected.

Results

Among 225 patients (60 from Vietnam and 165 from Korea), 140 and 85 were diagnosed with UC and CD, respectively. Severe activity (p < 0.01) and extensive colitis (p < 0.01) in UC, along with complicated behavior in CD (p < 0.01), were more frequently observed in Vietnamese patients compared to Korean patients. The proportion of UC patients using corticosteroids (p < 0.01), immunomodulators (p < 0.01), and biologics (p = 0.026) was significantly higher in Vietnam. In contrast, the proportion of UC patients using topical mesalamine (p < 0.01) was significantly higher in Korea. The intervals from CD diagnosis to biologic therapy initiation (p = 0.04), as well as from UC diagnosis to corticosteroid (p < 0.01), immunomodulator (p < 0.01), and biologic therapy (p < 0.01) commencement, were significantly shorter in Vietnamese patients compared to Korean patients. However, the proportions of endoscopic healing and complications at 1-year follow-up did not significantly differ between the countries (p > 0.05).

Conclusions

Although Vietnamese IBD patients had higher baseline clinical and phenotypic severity than their Korean counterparts, no significant differences in short-term outcomes were observed, potentially reflecting the impact of the higher rate and early biologic usage in Vietnamese patients.

Thiopurines Have Sustained Long-term Effectiveness in Patients with Inflammatory Bowel Disease, Which is Independent of Disease Duration at Initiation: A Propensity Score Matched Analysis

BACKGROUND AND AIMS

Thiopurines are viable option for the treatment of inflammatory bowel disease [IBD] in resource-limited countries. However, data on the effect of disease duration at thiopurines initiation on long-term effectiveness are limited.

METHOD

We performed a propensity matched analysis of a retrospective cohort of patients with ulcerative colitis [UC] and Crohn's disease [CD]. Patients initiated on thiopurines early in the disease course [≤2 years] were compared with those started late [>2 years]. Effectiveness was defined as no requirement for hospitalisation, anti-tumour necrosis factor [TNF] agents, or surgery, and minimum steroid requirement [≤1 steroid course in 2 years] during follow-up.

RESULTS

A total of 988 [UC: 720, CD: 268] patients were included (male: 665 [60.8%], median age: 40 [32-51] years, median follow-up: 40 [19-81] months). Overall effectiveness at 5 and 10 years was 79% and 72% in UC, and 69% and 63% in CD, respectively. After propensity score matching, there was no difference in 5- and 10-year effectiveness between early and late thiopurine initiation groups either for UC [81% and 80% vs 82% and 74%; p = 0.92] or CD [76% and 66% vs 72% and 51%, p = 0.32]. Male sex for UC (negative: hazard ratio [HR]: 0.67, 95% confidence interval [CI): 0.45-0.97; p = 0.03), and ileal involvement [positive: HR: 3.03, 95% CI: 1.32-6.71; p = 0.008], steroid-dependent disease [positive: HR: 2.70, 95% CI: 1.26-5.68; p = 0.01] and adverse events [negative: HR: 0.47, 95% CI:0.27-0.80; p = 0.005] for CD were predictors of thiopurine effectiveness.

CONCLUSION

Thiopurines have sustained long-term effectiveness in both UC and CD. However, early thiopurine initiation had no better effect on long-term disease outcome compared with late initiation.

The epidemiology of inflammatory bowel disease in Asia and Asian immigrants to Western countries

Inflammatory bowel disease (IBD), which comprises Crohn's disease and ulcerative colitis, is an idiopathic inflammatory condition of the gastrointestinal tract. The incidence and prevalence of IBD are rapidly increasing worldwide, particularly in newly industrialized regions such as Asia. Although a large medical armamentarium is available for treating this chronic disease, IBD imposes a marked global disease burden. To understand the complex etiopathogenesis of this condition, it is important to consider the rapidly changing trends in its epidemiology in Asia. During the past few decades, the incidence and prevalence of IBD have significantly increased in both Asian countries and Asian immigrants in Western countries. In this review, we aimed to study and update the epidemiology of IBD in diverse Asian regions and among Asian immigrants in North America and Europe. Moreover, we highlighted that this population exhibits a unique disease phenotype, such as male predominance and high frequency of perianal fistula in Crohn's disease. Also, a different disease phenotype including more complicated disease such as perianal complications was noted in Asian Americans and Asian Europeans.

Temporal Changes in the Treatment Paradigm and Long-term Prognosis of Patients With Crohn's Disease: A Hospital-Based Cohort Study in China

BACKGROUND

The temporal trends in medical treatment and long-term outcomes of patients with Crohn's disease (CD) have not been well elucidated in China over the past 2 decades. Accordingly, we aimed to evaluate the treatment paradigm and long-term clinical course of Chinese patients with CD in a hospital-based cohort.

METHODS

All adult patients newly diagnosed with CD (n = 1338) between 1999 and 2019 in the Sir Run Run Shaw Hospital were included in this cohort. Medication utilization, disease outcomes, and risk factors were investigated.

RESULTS

Overall, 48.7%, 35.6%, 67.8%, and 61.6% of patients used 5-aminosalicylates (5-ASA), corticosteroids, thiopurines, and infliximab (IFX), respectively. The cumulative risk of 5-ASA and corticosteroid initiation decreased during follow-up, whereas that of IFX initiation increased. Throughout a median follow-up duration of 26.4 (interquartile range, 12.0-49.2) months, a total of 486 and 300 patients underwent hospitalization and surgery, respectively. Of the 1097 patients with B1/B2 disease behavior at diagnosis, 10.3% experienced phenotype progression. The hospitalization rate decreased after 2015; however, surgery and phenotype progression rates did not significantly change. A Cox regression analysis indicated that IFX use since diagnosis was a contributing factor for lower rates of hospitalization and phenotype progression, whereas thiopurine use was associated with a lower surgery rate.

CONCLUSIONS

Infliximab use was observed to increase as 5-ASA and corticosteroid use decreased. Additionally, hospitalization rates decreased following temporal changes in IFX management, yet the surgery and phenotype progression rates remained the same.

Current status of IBD and surgery of Crohn's disease in Thailand

Inflammatory bowel disease (IBD) consists of two diseases: ulcerative colitis (UC) and Crohn's disease (CD). The incidence of IBD is much higher in Western countries compared to Asian countries, especially in Thailand. The incidence of UC in Thailand is quite low and seems less aggressive than in Western countries. Over the past two decades, the evolution of UC management in Thailand has led to a reduction in hospitalization and colectomy rate. Regarding CD, the majority of patients have an inflammatory phenotype at diagnosis. Diagnosis of CD remains challenging in Thailand as the time from onset of symptoms to diagnosis is quite delayed, possibly due to unawareness and difficulty in the differential diagnosis between CD and other infectious entero-colitis such as intestinal tuberculosis. With a significant trend to early initiation of immunomodulators and biologics, the cumulative rate of surgery after diagnosis has been improved. To improve the outcomes of CD treatment in Thailand, physicians need more awareness to recognize the disease, which results in early diagnosis, prevention of long-term complications, and reduction in the rate of surgery.