Comparing primary prevention with secondary prevention to explain decreasing coronary heart disease death rates in Ireland, 1985-2000.
BACKGROUND
To investigate whether primary prevention might be more favourable than secondary prevention (risk factor reduction in patients with coronary heart disease(CHD)).


METHODS
The cell-based IMPACT CHD mortality model was used to integrate data for Ireland describing CHD patient numbers, uptake of specific treatments, trends in major cardiovascular risk factors, and the mortality benefits of these specific risk factor changes in CHD patients and in healthy people without recognised CHD.


RESULTS
Between 1985 and 2000, approximately 2,530 fewer deaths were attributable to reductions in the three major risk factors in Ireland. Overall smoking prevalence declined by 14% between 1985 and 2000, resulting in about 685 fewer deaths (minimum estimate 330, maximum estimate 1,285) attributable to smoking cessation: about 275 in healthy people and 410 in known CHD patients. Population total cholesterol concentrations fell by 4.6%, resulting in approximately 1,300 (minimum estimate 1,115, maximum estimate 1,660) fewer deaths attributable to dietary changes(1,185 in healthy people and 115 in CHD patients) plus 305 fewer deaths attributable to statin treatment (45 in people without CHD and 260 in CHD patients). Mean population diastolic blood pressure fell by 7.2%, resulting in approximately 170 (minimum estimate 105, maximum estimate 300) fewer deaths attributable to secular falls in blood pressure (140 in healthy people and 30 in CHD patients), plus approximately 70 fewer deaths attributable to antihypertensive treatments in people without CHD. Of all the deaths attributable to risk factor falls, some 1,715 (68%) occurred in people without recognized CHD and 815(32%) in CHD patients.


CONCLUSIONS
Compared with secondary prevention, primary prevention achieved a two-fold larger reduction in CHD deaths. Future national CHD policies should therefore prioritize nationwide interventions to promote healthy diets and reduce smoking.
Kabir
Zubair
Z
Harvard School of Public Health, Division of Public Health Practice, Boston, USA. zkabir@hsph.harvard.edu <zkabir@hsph.harvard.edu>
Bennett
Kathleen
K
Shelley
Emer
E
Unal
Belgin
B
Critchley
Julia A
JA
Capewell
Simon
S
D000368:Aged; D000369:Aged, 80 and over; D003327:Coronary Disease / Q000401:mortality* / Q000517:prevention & control*; D005260:Female; D015438:Health Behavior; D006801:Humans; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors / Q000627:therapeutic use; D006937:Hypercholesterolemia / Q000453:epidemiology / Q000517:prevention & control*; D006973:Hypertension / Q000453:epidemiology / Q000517:prevention & control; D007494:Ireland / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D009026:Mortality / Q000639:trends; D012307:Risk Factors; D012907:Smoking / Q000453:epidemiology; D016540:Smoking Cessation; D000074606:Smoking Prevention
D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors