1524 DRUG-INDUCED POSTURAL HYPOTENSION: CLUSTER ANALYSIS OF CO-PRESCRIPTION PATTERNS IN OLDER PEOPLE IN UK PRIMARY CARE

Introduction Over 250 medications are reported to cause postural hypotension, associated with serious adverse outcomes in older adults. Studies in the literature and guidelines suggest a harmful cumulative risk of postural hypotension with multiple medication use. However, there is limited evidence on the potential for harm in practice, particularly which drugs are co-prescribed and may increase risk of postural hypotension. Methods Retrospective cohort study and cluster analysis using general practice data from IQVIA Medical Research Data (IMRD) in patients aged ≥50 contributing data between 1 Jan 2018 and 31 Dec 2018. Thirteen drug groups known to be associated with postural hypotension by mechanism were analysed and clusters generated by sex and age-band. Results 602,713 individuals aged ≥50 with 283,912 (47%) men and 318,801 (53%) women were included. The most prevalent prescriptions that might contribute to postural hypotension were angiotensin converting enzyme (ACE) inhibitors, calcium-channel blockers, beta-blockers, selective serotonin reuptake inhibitors and uroselective alpha-blockers. We identified distinct clusters of cardiovascular system (CVS) drugs in men and women at all ages. CVS plus psychoactive drug clusters were common in women at all ages, and in men aged ≤70. CVS plus uroselective alpha-blockers were identified in men aged ≥70. Conclusion Distinct clusters of drugs associated with postural hypotension are commonly prescribed in practice, which change over the life course in men and women. Our findings highlight potentially harmful drug combinations that may cause a cumulative risk of postural hypotension in older people. This may guide clinicians about the potential of synergistic harm and to monitor for postural hypotension if using such combinations – particularly in patients aged ≥70 or at high-risk due to comorbidity.