Should treatment of mild to moderate hypertension be targeted? Results from a Markov cohort model incorporating multiple risk factors.
A series of guidelines for the treatment of mild to moderate hypertension have recommended that individuals with multiple cardiovascular risk factors should start treatment sooner, or at a lower level of diastolic pressure, compared with patients with an isolated elevation of blood pressure. A Markov cohort model was constructed to examine this claim. The cohorts consisted of mild to moderately hypertensive men with added cardiovascular risk factors: smoking, raised serum cholesterol, and presence of left ventricular hypertrophy on electrocardiogram. The results of the model confirm that the prognosis of hypertension is highly dependent on the presence of other risk factors. The average remaining life expectancy of two patients of identical age and level of diastolic pressure varied by as much as 10 to 24 years, depending on the presence of other risk factors. Depending on the patient, the gain in life expectancy due to treatment of hypertension ranged from 0.11 years to 1.03 years. However, the results also indicated that the additional benefit as a result of 'targeting' in people with multiple risk factors did not exceed 0.47 years for any of the patient categories analysed. The nature of these conclusions remained unaltered despite the use of quality-adjusted life years (QALYs), and varying assumptions about the benefit of treatment. In comparison the model indicated that the benefits of smoking cessation among hypertensive men were three to eight times greater than the expected benefits from antihypertensive therapy.
Kawachi
I
I
Department of Community Health, Wellington School of Medicine, New Zealand.
Purdie
G
G
D000328:Adult; D000959:Antihypertensive Agents / Q000627:therapeutic use; D001794:Blood Pressure / Q000187:drug effects; D006332:Cardiomegaly / Q000453:epidemiology / Q000503:physiopathology; D002784:Cholesterol / Q000097:blood; D015331:Cohort Studies; D004562:Electrocardiography; D006287:Health Planning Guidelines; D006801:Humans; D006973:Hypertension / Q000188:drug therapy* / Q000453:epidemiology / Q000503:physiopathology; D008017:Life Expectancy; D008297:Male; D008875:Middle Aged; D008954:Models, Biological; D012307:Risk Factors; D012907:Smoking / Q000453:epidemiology / Q000503:physiopathology
D000959:Antihypertensive Agents; D002784:Cholesterol