Ischaemic heart disease: trends in mortality in Hong Kong, 1970-89.
OBJECTIVE
To describe the time trends for ischaemic heart disease (IHD) mortality in Hong Kong between 1970 and 1989, and to examine these trends in relation to the risk factors for IHD.


METHODS
A descriptive epidemiological study of time trends using mortality and population data from the Hong Kong Census and Statistics Department. Direct standardisation using the world population was made to adjust for the changing age structure. Log-linear analyses for trends were performed for the whole period and separately for 1970-79 and 1980-89. The cohort effect was studied by regrouping the data into five year groups according to the year of birth. The influences of risk factors, including hypertension, diet, and smoking, on the time trends of IHD were explored. The role of improved hospital treatment of myocardial infarction on the trends of mortality from categories of IHD was also examined.


METHODS
The total Hong Kong population, 1970-89.


RESULTS
The substantial and steady decline of IHD mortality seen in most western countries in the past two decades was not observed in Hong Kong, which showed a plateau or slowly decreasing trend only in the past decade for both women and men. The decreasing trends were more apparent in the younger age groups, especially for women. Cohort analysis showed no significant cohort effect in men, but women born more recently had a lower mortality. Trends of risk factors did not show any close relationship with the mortality trends of IHD, except that a decrease in cigarette smoking might have contributed to the slight decrease in IHD mortality in recent years. Better detection and wider availability of treatment for hypertension might also have contributed to the decrease in IHD mortality.


CONCLUSIONS
Hong Kong started to show a slow decline in IHD mortality during the 1980s, about one to two decades later than in other western countries and with the decreasing trend less pronounced. The reasons for this decline are not clear. More detailed information from systematic, population based surveys on life style and risk factors for IHD among the general population are needed.
Yu
T S
TS
Department of Community and Family Medicine, Chinese University of Hong Kong, Lek Yuen Health Centre, Shatin, New Territories.
Wong
S L
SL
Lloyd
O L
OL
Wong
T W
TW
D000328:Adult; D000367:Age Factors; D000368:Aged; D015331:Cohort Studies; D005260:Female; D006723:Hong Kong / Q000453:epidemiology; D006760:Hospitalization; D006801:Humans; D006973:Hypertension / Q000401:mortality; D008019:Life Style; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000401:mortality; D017202:Myocardial Ischemia / Q000401:mortality*; D015995:Prevalence; D012044:Regression Analysis; D012737:Sex Factors; D012907:Smoking / Q000401:mortality; D013997:Time Factors