Obstructive sleep apnoea (OSA) is a common condition where the walls of the throat relax and narrow during sleep, interrupting normal breathing. It affects 510% of the adult population. OSA patients are more likely to get beta-blocker treatment (a type of cardiac medication) because of co-existing conditions of hypertension, chest pain, heart attack, abnormal heart rhythm and chronic heart failure. However beta blockers may increase or decrease the risk of sudden death in OSA patients. The proposed study is to investigate whether the use of beta-blockers is associated with harm or benefit when given to OSA patients using the UK routinely collected primary care health data. The results will answer an important research question of the role of beta-blockers in OSA patients and provide solid evidence in helping decision making of clinical practice in term of drug management in OSA patients.
Methods: This is a population-based cohort study using the Clinical Practice Research Datalink (CPRD) database. Patients with OSA who were prescribed at least two prescriptions of beta-blockers between 1986 and 2016 will form the exposure cohort. A propensity score matched cohort (1:2 matching) will be selected from patients who were not prescribed beta-blockers. The primary outcome will be sudden death during the follow up time. The secondary outcomes will include pacemaker insertion, myocardial infarction, heart failure, atrial fibrillation, cancer and all-cause mortality.
Data analysis: Cox proportional hazards regression models will be used to determine the association between the use of beta-blockers and the study outcomes. Univariate and multivariate analyses will be carried out. In the multivariate models the hazard ratios will be adjusted for all known covariates. The results will be expressed as hazards ratios and 95% confidence intervals. We will also perform a number of sensitivity analyses to address missing data and to make sure the results are robust.
Sudden death
Pacemaker insertion
Myocardial infarction
Heart failure
Atrial fibrillation
Cancer
All-cause mortality
Li Wei - Chief Investigator - University College London ( UCL )
Li Wei - Corresponding Applicant - University College London ( UCL )
Allan Struthers - Collaborator - University of Dundee
Thomas MacDonald - Collaborator - University of Dundee