High prevalence of duodenal ulcer in Indochinese immigrants attending an Australian university hospital.

Indochinese migrants to Australia appear to have a high prevalence of duodenal ulcer (DU). To examine this hypothesis a 2 year audit of the prevalence of symptomatic DU among patients attending a general hospital was conducted. The last 6 months of this period included a prospective assessment of ulcer risk factors. In Australian-born patients DU prevalence was 8.4 per 1000 admissions. By comparison, prevalence in Indochinese was 24.6 per 1000 admissions (P < 0.001) with an age standardized prevalence of 30.3 per 1000 (P < 0.001). This represented a relative risk in Indochinese of 2.9 using crude data and 3.6 after age standardization. The increased risk was demonstrated only in males: very few DU were diagnosed in female Indochinese. Ulcer prevalence increased in Indochinese for each age decile between 10 and 80 years, with statistical significance (P < 0.01) reached in the age brackets 0-19, 20-39 and 60-79 years. Ulcer prevalence was also increased in some other ethnic groups. However, when referral bias was taken into account (by calculating the ratio of endoscopies to total admissions for each group), a significant increase in DU prevalence could only be confidently demonstrated in Indochinese. Analysis of risk factors showed that among DU patients, Indochinese were significantly less likely to smoke (P < 0.05) and also had a tendency to ingest less non-steroidal anti-inflammatory drugs (NSAID) and to consume less alcohol.