METHODS: A population-wide hospital discharge database in Singapore was used to identify all hospital admissions with a primary discharge diagnosis of PACG (International Classification of Disease-CM code: 365.2). The Singapore census was used for denominator data.

RESULTS: Between 1993 and 1997 there were 894 hospital admissions for PACG. The mean annual rate of PACG admissions was 11.1 per 100 000 (95% confidence interval (CI), 10.4, 11.8) among people aged 30 years and over. The annual rate was highest for Chinese (age and sex adjusted rate: 12.2 per 100 000), which was twice that of Malays (6.0 per 100 000) and Indians (6.3 per 100 000). Females had two times higher rates than males in all three races (age adjusted relative risk: 2.0, 95% CI: 1.7, 2.3).