Cor Vasa 2003, 44(5):249-255
Intervention of the risk factors of atherosclerosis and cardiovascular mortality. A 20-year primary prevention study from a statistician's point of view
- 1 EuroMISE centrum-Kardio, Ústav informatiky Akademie věd České republiky
- 2 EuroMISE centrum-Kardio, II. interní klinika, Všeobecná fakultní nemocnice a 1. lékařská fakulta Univerzity Karlovy, Praha, Česká republika
Aims:
To evaluate intervention of the risk factors of atherosclerosis (ARF) in relation to mortality from atherosclerotic cardiovascular disease (CVD) in a 20-year primary prevention multifactorial study, conducted by workers of the Department of Internal Medicine II, General University Hospital in Prague 2, and to point to methodological problems associated with this longitudinal study.
Patients and methods:
Entry examination in the years 1975-1979 was performed in 59.8% (1,417) of the 2,370 invited middle-aged men resident in Prague 2. Overall, 859 men were included into a risk group (RG) randomly divided into an intervened RG (IRG; n = 427) and a control group (CRG; n = 432). IRG was under the supervision by specialists while CRG patients continued to be taken care of by district or works physicians.
Results:
Statistically significant differences (medically not substantial) between IRG and CRG were present in only some years in the first half of the study in terms of the numbers of cigarettes in smokers, and in systolic blood pressure levels in hypertensives. The relative risk of death from atherosclerotic CVD was non-significantly lower in IRG (0.94; 95% confidence interval (0.65; 1.35)) compared with CRG.
Conclusion:
The non-significance of the difference in mortality rates between IRG (7.6 deaths per 1,000 person-years) and CRG (8.1 deaths per 1,000 person-years) was the consequence of methodological flaws of the study, particularly the low power of the study and inconsistent differentiation of health care (among other things, also for ethical reasons) between IRG and CRG.
Keywords: Primary prevention study; Longitudinal study; Risk factors; Atherosclerosis; Mortality; Cardiovascular disease
Published: May 1, 2003 Show citation