Comparison of usefulness of systolic, diastolic, and mean blood pressure and pulse pressure as predictors of cardiovascular death in patients ≥60 years of age (The Dubbo Study)

Abstract

Blood pressure (BP) is an important predictor of future cardiovascular risk. Clinicians have traditionally recognized the importance of systolic BP, especially in older adults. 1 The sixth report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure. Arch Intern Med. 1997; 157: 2413-2446 Crossref PubMed Google Scholar BP is also characterized by its pulsatile (estimated by pulse pressure [PP]) and steady (estimated by mean arterial pressure) components. 2 Darne B. Girerd X. Safar M. Cambien F. Guize L. Pulsatile versus steady component of blood pressure a cross-sectional analysis and a prospective analysis on cardiovascular mortality. Hypertension. 1989; 13: 392-400 Crossref PubMed Scopus (533) Google Scholar Two recent studies 3 Glynn R.J. Chae C.U. Guralnik J.M. Taylor J.O. Hennekens C.H. Pulse pressure and mortality in older people. Arch Intern Med. 2000; 160: 2765-2772 Crossref PubMed Scopus (196) Google Scholar , 4 Staessen J.A. Gasowski J. Wang J.G. Thijs L. Den Hond E. Boissel J.P. Coope J. Ekbom T. Gueyffier F. Liu L. et al. Risks of untreated and treated isolated systolic hypertension in the elderly meta-analysis of outcome trials. Lancet. 2000; 355: 865-872 Abstract Full Text Full Text PDF PubMed Scopus (1029) Google Scholar have emphasized the importance of PP, defined as systolic BP minus diastolic BP, as a predictor of cardiovascular events or mortality in the elderly. Another study 5 Domanski M.J. Davis B.R. Pfeffer M.A. Kastantin M. Mitchell G.F. Isolated systolic hypertension prognostic information provided by pulse pressure. Hypertension. 1999; 34: 375-380 Crossref PubMed Scopus (329) Google Scholar highlighted mean BP, defined as 1/3 systolic BP plus 2/3 diastolic BP, as a predictor of cardiovascular disease risk. Data from the Framingham Heart Study 6 Franklin S.S. Gustin W.T. Wong N.D. Larson M.G. Weber M.A. Kannel W.B. Levy D. Hemodynamic patterns of age-related changes in blood pressure. The Framingham Heart Study. Circulation. 1997; 96: 308-315 Crossref PubMed Scopus (1755) Google Scholar and other studies 7 Tate R.B. Manfreda J. Krahn A.D. Cuddy T.E. Tracking of blood pressure over a 40-year period in the University of Manitoba Follow-up Study, 1948–1988. Am J Epidemiol. 1995; 142: 946-954 PubMed Google Scholar indicate that systolic BP increases continuously with age, whereas diastolic BP increases until age 60 years and then begins to decrease steadily. As a result, PP may become a more important BP measurement associated with cardiovascular disease in older persons. 8 Franklin S.S. Khan S.A. Wong N.D. Larson M.G. Levy D. Is pulse pressure useful in predicting risk for coronary heart Disease? The Framingham Heart Study. Circulation. 1999; 100: 354-360 Crossref PubMed Scopus (1497) Google Scholar Darne et al 2 Darne B. Girerd X. Safar M. Cambien F. Guize L. Pulsatile versus steady component of blood pressure a cross-sectional analysis and a prospective analysis on cardiovascular mortality. Hypertension. 1989; 13: 392-400 Crossref PubMed Scopus (533) Google Scholar were among the first to report that PP, in addition to mean BP, was an independent cardiovascular risk factor. Mean BP has not been as extensively studied, with positive associations with cardiovascular disease in some 5 Domanski M.J. Davis B.R. Pfeffer M.A. Kastantin M. Mitchell G.F. Isolated systolic hypertension prognostic information provided by pulse pressure. Hypertension. 1999; 34: 375-380 Crossref PubMed Scopus (329) Google Scholar , 9 Benetos A. Safar M. Rudnichi A. Smulyan H. Richard J.L. Ducimetieere P. Guize L. Pulse pressure a predictor of long-term cardiovascular mortality in a French male population. Hypertension. 1997; 30: 1410-1415 Crossref PubMed Scopus (958) Google Scholar , 10 Dyer A.R. Stamler J. Shekelle R.B. Schoenberger J.A. Stamler R. Shekelle S. Collette P. Berkson D.M. Paul O. Lepper M.H. Lindberg H.A. Pulse pressure-III. Prognostic significance in four Chicago epidemiologic studies. J Chronic Dis. 1982; 35: 283-294 Abstract Full Text PDF PubMed Scopus (55) Google Scholar but not all 11 Franklin S.S. Sutton-Tyrrell K. Belle S.H. Weber M.A. Kuller L.H. The importance of pulsatile components of hypertension in predicting carotid stenosis in older adults. J Hypertens. 1997; 15: 1143-1150 Crossref PubMed Scopus (122) Google Scholar studies. It remains unclear which measures of BP, either alone or in combination, best predict the risk of cardiovascular disease mortality. Therefore, we studied the use of systolic BP, diastolic BP, PP, and mean BP in an elderly cohort of men and women aged ≥60 years at baseline with no history of cardiovascular disease. Using BP values at baseline, we compared the associations of each BP measure with the risk of cardiovascular disease mortality prospectively over 12 to 13 years of follow-up.