Phenotypic Differences and Clinical Outcomes of South Asian Children With IBD: A Singapore-Malaysia Study From the...

Existing literature largely contrasts pediatric inflammatory bowel disease (PIBD) phenotypic differences and outcomes of South Asians (SAs) with Caucasians. No published comparative data exist between SAs and non-SAs within Asia-Pacific. We aim to validate these comparisons within Asia-Pacific, comparing SAs ("Indian," "Bangladeshi," "Nepali," "Pakistani," "Sri Lankan (Sinhalese/Tamil)," and "Maldivian") with their non-SA ("Chinese," "Malay," "Eurasian", or "Others") counterparts in the multiethnic populations of Singapore and Malaysia.

Clinical data from three centers in Singapore and Malaysia were compared, at baseline, 1-year (1YFU) and 5-year (5YFU) post-diagnosis, between SAs and non-SAs.

Baseline, 1YFU, and 5YFU data were analyzed in 366, 260 (71.0%), and 127 (34.7%) patients, respectively. Compared with non-SAs, SAs were significantly older (10.2 vs. 9.1 years, p = 0.013), had less very early-onset disease (15.5% vs. 33.0%, p = 0.001), a shorter time from symptom onset to diagnosis (5.9 vs. 8.9 months, p = 0.024), less growth retardation (5.9% vs. 14.0%, p = 0.035), and less comorbid liver diseases (1.4% vs. 9.4%, p = 0.002). SAs with Crohn's disease had more symptomatic perianal disease (18.3% vs. 9.4%, p = 0.016) and less isolated ileal L1 disease (10.2% vs. 20.7%, p = 0.057). No significant differences in induction therapies, maintenance immunosuppression or remission rates at 1YFU were noted, but at 5YFU, SAs had significantly lower rates of clinical remission (SA = 68.3% vs. non-SA = 84.9%, p = 0.036), steroid-free remission (SA = 53.7% vs. non-SA = 73.3%, p = 0.043), and mucosal healing (calprotectin < 300 ug/g, 0.0% vs. 80.0%, p = 0.048).

We report unique phenotypic differences in SA and non-SA children with IBD. SAs had poorer long-term clinical outcomes, although short-term outcomes and therapy usage patterns were comparable.