Objective: The overall cardiovascular prognosis of isolated systolic hypertension, isolated diastolic hypertension and pulse pressure defined with home blood pressure (BP) measurements remains unclear.
Methods: A prospective nationwide study was initiated in 2000–2001 on 1924 randomly selected participants aged 44–74 years. We determined home and office BP at baseline and classified the individuals into four groups according to their home BP levels: normotension, isolated diastolic hypertension, isolated systolic hypertension and systolic–diastolic hypertension. The primary endpoint was incidence of a composite cardiovascular event.
Results: After a median follow-up of 11.2 years, 236 individuals had suffered a cardiovascular event. In multivariable Cox proportional hazard models, the relative hazards and 95% confidence intervals (CIs) for cardiovascular events were significantly higher in participants with isolated diastolic hypertension (relative hazard 1.95; 95% CI, 1.06–3.57; P = 0.03), isolated systolic hypertension (relative hazard 2.08; 95% CI, 1.42–3.05; P < 0.001) and systolic–diastolic hypertension (relative hazard 2.79; 95% CI, 2.02–3.86; P < 0.001) than in participants with normotension. Home (relative hazard 1.21; 95% CI, 1.05–1.40; P = 0.009 per 10 mmHg increase), but not office (relative hazard 1.10; 95% CI, 1.00–1.21, P = 0.06) pulse pressure, adjusted for mean arterial pressure, was an independent predictor of cardiovascular risk.
Conclusion: Isolated diastolic and systolic hypertension defined with home measurements are associated with an increased cardiovascular risk. Close follow-up and possible treatment of these patients is therefore warranted. Home-measured pulse pressure is an independent predictor of cardiovascular events while office-measured pulse pressure is not, which fortifies the view that home BP provides more accurate risk prediction than office BP.
aPopulation Studies Unit, National Institute for Health and Welfare, Turku
bPopulation Health Research Unit, National Institute for Health and Welfare, Helsinki, Finland
Correspondence to Teemu Niiranen, MD, Population Studies Unit, National Institute for Health and Welfare, Peltolantie 3, 20720 Turku, Finland. Tel: +358 50 3306863; fax: +358 2 3316720; e-mail: firstname.lastname@example.org
Abbreviations: BP, blood pressure; IDH, isolated diastolic hypertension; ISH, isolated systolic hypertension; SDH, systolic–diastolic hypertension
Received 4 May, 2013
Revised 6 November, 2013
Accepted 6 November, 2013