Antihypertensive treatment after stroke and all-cause mortality--an analysis of the General Practitioner Research Database (GPRD).
BACKGROUND
Randomised controlled trials have shown a beneficial effect of antihypertensive treatment on stroke recurrence. The effect of antihypertensive treatment on survival and recurrence in an unselected sample of the general population, using the General Practice Research Database, was analysed.


METHODS
Cox regression estimating the effect of antihypertensive treatment on survival and stroke recurrence >1 year among 44,244 first-ever strokes in the UK from 1997 to 2006 was adjusted by propensity score analysis considering gender, age, general practice, stroke year, drug prescriptions and diagnostic codes from other diseases.


RESULTS
The EU standardised stroke incidence was 118 per 100,000 (95% CI = 117-120). The 90-day case fatality was 19%. By 90 days after stroke 20,147 (58%) were diagnosed as having hypertension, of whom 75% had received antihypertensive treatment after stroke. After 5 years 68% of the hypertensive stroke patients receiving antihypertensive treatment were alive, while this proportion for patients not prescribed antihypertensive treatment was 59%. This could not be explained by potential confounders with an adjusted relative risk of 0.62 (95% CI = 0.58-0.66; p < 0.001) for antihypertensive treatment and premature death. The adjusted relative risk of antihypertensive treatment on stroke recurrence after 1 year, which was observed in 35% until 5 years after stroke, was 0.92 (95% CI = 0.84-1.01; p = 0.092).


CONCLUSIONS
A high proportion of hypertensive stroke patients did not receive antihypertensive treatment. The protective effect of antihypertensive treatment on survival was higher in this general population than reported in randomised controlled trials, while an effect of antihypertensive treatment on late stroke recurrence was borderline, but not significant.
Toschke
André Michael
AM
Department of Public Health Sciences,Division of Health and Social Care, King's College London, London, UK. michael.toschke@kcl.ac.uk
Wolfe
Charles D A
CD
Heuschmann
Peter Ulrich
PU
Rudd
Anthony G
AG
Gulliford
Martin
M
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000959:Antihypertensive Agents / Q000627:therapeutic use*; D016022:Case-Control Studies; D019992:Databases as Topic; D018572:Disease-Free Survival; D011307:Drug Prescriptions / Q000706:statistics & numerical data; D004739:England / Q000453:epidemiology; D005194:Family Practice / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D006973:Hypertension / Q000150:complications / Q000188:drug therapy* / Q000401:mortality*; D015994:Incidence; D008297:Male; D008875:Middle Aged; D016016:Proportional Hazards Models; D012008:Recurrence; D012042:Registries; D018570:Risk Assessment; D012307:Risk Factors; D020521:Stroke / Q000209:etiology / Q000401:mortality* / Q000517:prevention & control*; D013997:Time Factors; D016896:Treatment Outcome
D000959:Antihypertensive Agents