Trends in Prescription of Antihypertensive Medications in UK Primary Care Practices, 1988-2018

Date of ISAC Approval: 
26/07/2019
Lay Summary: 
Antihypertensive drugs are drugs prescribed to treat high blood pressure. They are one of the most commonly prescribed drugs in the world. Previous studies have found that the number of prescriptions of antihypertensive drugs have increased over time in the UK, however these studies are either outdated or are limited in scope. Using data from the Clinical Practice Research Datalink, we will describe prescribing patterns of antihypertensive drugs in UK clinical practices from 1988 to 2019. Findings from this study will provide an updated picture of the prescribing trends of antihypertensive drugs from the last 31 years.
Technical Summary: 
Antihypertensive drugs are one of the most commonly prescribed drugs worldwide. Few comprehensive studies exist that explore the prescription patterns of these drugs in UK clinical practices; most are either outdated, limited in scope, or too broad to accurately describe the prescription trends of antihypertensive drugs. An updated, comprehensive study describing prescription trends is currently needed. We will address this gap by using the UK CPRD to examine the annual prescription trends of antihypertensive drugs between April 1, 1988 and April 1, 2019. Crude and adjusted prescription rate and corresponding 95% confidence intervals will be determined using Poisson regression, and annual prescription rates will be stratified by age, sex, and type of antihypertensive drug class.
Health Outcomes to be Measured: 
The measured outcomes will be the annual number of patients with a prescription for each antihypertensive drug overall, by age group and by sex; crude and age-adjusted annual prevalence proportion, difference in prevalence and ratio of prevalence for each antihypertensive drug overall; crude annual prevalence proportion, difference in prevalence and ratio of prevalence between the years 1988 and 2019 only for each antihypertensive drug by age group and by sex. The crude and adjusted annual prevalence proportion, difference in prevalence and ratio of prevalence between the years 1988 and 2019 will also be calculated for each antihypertensive drug class.
Collaborators: 

Samy Suissa - Chief Investigator - McGill University
James Brophy - Collaborator - McGill University
Julie Rouette - Collaborator - McGill University
Dr Laurent Azoulay - Collaborator - McGill University
Samy Suissa - Corresponding Applicant - McGill University
Dr Tibor Schuster - Collaborator - McGill University