Little is known about whether patients with moderately high blood pressure (mild hypertension) and a low risk of heart attack/stroke should be given medication to lower blood pressure. A definitive trial is unlikely to happen because it would be too expensive and require too many patients. Yet many guidelines encourage pharmacological treatment, and many patients receive it despite little evidence of benefit.
This study will examine the extent to which patients are prescribed pharmacological treatment for low risk mild hypertension, and explore the safety and effectiveness of this treatment using data from a large database of Primary Care records. Death from all causes will be compared in patients prescribed blood pressure lowering medication and those not prescribed medication, matched by characteristics such as age, sex, smoking status, prescription of other medications and history of disease. This approach will allow the effectiveness of pharmacological treatment to be examined in a large number of patients, followed-up for many years. This study will inform hypertension management guidelines, potentially leading to improved patient care.
Evidence to guide the pharmacological treatment of patients with uncomplicated (low cardiovascular disease risk), mild hypertension (blood pressure 140/90-159/99mmHg) is lacking. A definitive trial is unlikely due to the costs and numbers of patients required because of low event rates in this population. Yet many guidelines encourage treatment, and many patients are thought to receive it, despite little evidence of benefit.
This study will examine the extent to which patients are prescribed treatment for uncomplicated, mild hypertension in routine practice and the safety and efficacy of this treatment for using data from a large database of Primary Care records. The primary outcome of the study will be the rate of all-cause mortality in patients with uncomplicated mild hypertension prescribed antihypertensive treatment vs. those not prescribed therapy, matched using propensity scores estimating the likelihood of receiving treatment. Secondary outcomes will include the rate of cardiovascular morbidity/mortality, side effects to medication and rate of cancer in treated vs. non treated patients. These outcomes will be assessed using Cox proportional hazards modelling. The proportion of patients given lifestyle advice and/or pharmacological treatment for uncomplicated mild hypertension will also be estimated by year, and predictors of lifestyle advice/pharmacological treatment will be examined using logistic regression.
Richard McManus - Chief Investigator - University of Oxford
James Sheppard - Corresponding Applicant - University of Oxford
Jonathan Mant - Collaborator - University of Cambridge
Richard Hobbs - Collaborator - University of Oxford
Richard Stevens - Collaborator - University of Oxford
Sarah Lay-Flurrie - Collaborator - University of Oxford
HES Admitted Patient Care;ONS Death Registration Data;Patient Level Index of Multiple Deprivation;Practice Level Index of Multiple Deprivation