Temporal trends and ethnic variations in asthma mortality in Singapore, 1976-1995

Background-A study was undertaken to examine temporal trends and ethnic dif ferences in the asthma mortality rate in Singapore. Methods-Asthma mortality rates in Singapore were estimated from vital data for the years from 1976 to 1995. Trends in sex and age specific (5-14, 15-3 4, 35-59, 60+ years) rates were obtained for four periods (1976-80, 1981-85 , 1986-90, 1991-95) and for Chinese, Malay, and Indian subjects for the yea rs when these data were available (1989-95). Results-An increase in asthma mortality was observed in children aged 5-14 years from 0.21 per 100 000 person years in 1976-80 to 0.72 per 100 000 per son years in 1991-95. No increases were noted in the other age groups but a small decrease was observed in the 1991-95 period for the 35-59 year age g roup. Marked ethnic differences in mortality rates were observed. In the gr oup aged 5-34 years the asthma mortality rates were 0.5 per 100 000 in Chin ese subjects, 1.3 per 100 000 in Indians, and 2.5 per 100 000 in Malay subj ects. Similar 2-4 fold differences were observed in all other age groups. Conclusions-Apart from genetic factors, environmental exposures and medical care factors which influence asthma prevalence and severity are most Likel y to be the causes of the observed temporal trends and ethnic differences i n the asthma mortality rate in Singapore, but further studies are needed to elucidate these more fully.