Background and purpose: The PROGRESS trial (Perindopril Protection Against Recurrent Stroke Study) conducted in the early 1990s showed that blood pressure (BP) lowering therapy reduced the risks of recurrent stroke by about 50% after spontaneous intracerebral hemorrhage (ICH). However, the ICH subgroup was a minority, and trial cohorts are invariably selective. Therefore, it is unclear whether the impact of BP control on risk of recurrent stroke in ICH observed in PROGRESS would be as great in real-world practice.
Methods: We compared BP control (mean BP during study follow-up) and risks of recurrent stroke after first-ever primary ICH in 2 colocated population-based studies before and after the PROGRESS trial (1995–2001) in Oxfordshire: Oxfordshire Community Stroke Project (OCSP; 1981–1986) and OXVASC (Oxford Vascular Study; 2002–2018).
Results: Two hundred seventy-seven patients (753 patient-years of follow-up) with first-ever primary ICH were ascertained in OXVASC and OCSP. Baseline systolic BP was comparable between the 2 studies (mean/SD=183.8/36.5 in OXVASC versus 178.1/38.2 in OCSP, P=0.30) but among one hundred thirty-seven 90-day survivors, mean BP during follow-up was substantially lower in OXVASC versus OCSP (135.2/16.4 versus 157.3/17.8, P<0.0001). Risks of recurrent stroke (per 100 patient-years) decreased from 10.3 (95% CI, 4.7–19.5) in OCSP to 3.1 (1.8–4.8) in OXVASC (P=0.006), predominantly driven by a reduction at younger ages (5-year risk at age <75 years: 35.4% versus 6.9%, P=0.001; hazard ratio, 0.14 [0.04–0.54]).
Conclusions: Risks of recurrent stroke after primary ICH have fallen significantly in Oxfordshire over the past 4 decades, coinciding with substantial improvements in BP control during follow-up.
Keywords: blood pressure; cerebral hemorrhage; ischemic stroke; risk; survivors.