Hypertension, commonly known as high blood pressure (BP), is a prevalent condition where the force of blood against the artery walls is elevated, potentially leading to heart diseases. This global issue affects around 1 billion adults worldwide. The severity of hypertension is determined by the level of BP, which also guides the treatment goal (known as target BP level). Over time, the target BP levels have changed. According to recent guidelines, which recommend a more aggressive approach to BP management, more patients will use BP lowering medications and will have lower treatment targets. However, certain aspects of these guidelines are based solely on expert opinion, and limited clinical evidence exists regarding this issue. There is therefore an urgent need to generate relevant evidence using real-world data to examine this issue.
We aim to examine different BP control plans using Clinical Practice Research Datalink by including patients who initiated any antihypertensive therapy between 1998 and 2018. Initially, we will investigate whether targeting a lower BP level for treatment-naive patients at low risk of heart problems results in delayed and reduced occurrences of heart diseases compared to higher BP levels. The ultimate goal is to devise a personalized BP control plan for patient with high blood pressure regardless of their cardiovascular risk level.
Blood pressure level is used to classify the severity of hypertension and to determine treatment goals (i.e., target BP level), both of which changed over time. Treatment guidelines were recently revised to incorporate the results from two large randomized controlled trials (RCTs), ACCORD and SPRINT. However, those studies did not assess BP for patients at low cardiovascular disease (CVD) risk. To address this important knowledge gap, we will emulate a target trial using a retrospective, population-based cohort study to compare the risk of adverse cardiovascular events among patients following different dynamic blood pressure treatment strategies. This study will involve CPRD Gold data linked to Hospital Episode Statistics Admitted Patient Care, Office for National Statistics, and Index of Multiple Deprivation data. In the primary analysis, we will compare an intensive BP control plan (systolic blood pressure [SBP] ≤130 mm Hg and diastolic blood pressure [DBP] ≤80 mm Hg) and conservative BP control plan (SBP ≤140 mm Hg and DBP ≤90 mm Hg) to an extremely loose BP control plan (SBP ≤150 mm Hg and DBP ≤90 mm Hg) for patients with hypertension at low CVD risk. In secondary analyses, we will explore dynamic, personalized plans for all patients with hypertension regardless of estimated CVD risk. The primary outcome will be the occurrence of major adverse cardiovascular events, a composite endpoint that include cardiovascular death, myocardial infarction, and ischemic stroke. Dynamic marginal structural modelling and inverse-intensity-rate-ratio weight will be applied to minimize time-dependent confounding and differences in covariate-dependent follow-ups, respectively.
• Major adverse cardiovascular events, defined as a composite endpoint comprising nonfatal myocardial infarction, nonfatal stroke, and cardiovascular death.
• Myocardial Infarction
• Stroke
• Cardiovascular death
• Coronary revascularization
• Hospitalization for congestive heart failure
• Hospitalization for angina
• Severe adverse events related to antihypertensive treatment (e.g., hypotension, syncope, electrolyte abnormalities, bradycardia, and acute kidney injury or failure resulting in emergency room visits or hospitalizations).
Samy Suissa - Chief Investigator - Sir Mortimer B Davis Jewish General Hospital
Robert Platt - Corresponding Applicant - McGill University
Antonios Douros - Collaborator - McGill University
Kristian Filion - Collaborator - McGill University
pauline reynier - Collaborator - Sir Mortimer B Davis Jewish General Hospital
Qi Zhang - Collaborator - Sir Mortimer B Davis Jewish General Hospital
Tianze Jiao - Collaborator - University of Florida
HES Admitted Patient Care;ONS Death Registration Data;Practice Level Index of Multiple Deprivation