The association between antihypertensive treatment and serious adverse events by age and frailty: an observational cohort study of 3.8 million patients followed up for a decade

Conference:

SAPC ASM 2022 - UCLan

Talk Code:

3B.3

Presenter:

James Sheppard

Twitter:

@jamessheppard48

Co-authors:

Constantinos Koshiaris, Richard Stevens, Sarah Lay-Flurrie, Amitava Banerjee, Brandon K. Bellows, Andrew Clegg, FD Richard Hobbs, Subhashisa Swain, Juliet A Usher-Smith, Richard J McManus

Author institutions:

University of Oxford, University College London, Columbia University, University of Leeds, University of Cambridge

Problem

Antihypertensives are effective at reducing the risk of cardiovascular disease, but limited data exist quantifying their association with serious adverse events (SAEs), particularly in older people with frailty. This study examined this association using data from nationally representative electronic health record data.

Approach

This was a retrospective cohort study, utilising linked data from the Clinical Practice Research Datalink in England between 1998-2018. Eligible patients were aged 40+ years, with a systolic blood pressure reading between 130-179mmHg and not previously prescribed antihypertensive treatment. Outcomes were defined as hospitalisation or death within 10 years from falls (primary outcome), hypotension, syncope, fractures, acute kidney injury (AKI), electrolyte abnormalities and gout. The association between treatment and SAEs was examined by Cox regression adjusted for propensity score. Subgroup analyses were undertaken by age and frailty.

Findings

Of 3,834,056 patients followed for a median of 7.1 years, 484,187 (12.6%) were previously prescribed antihypertensive medication in the 12 months prior to the index date. Antihypertensives were associated with an increased risk of hospitalisation or death from falls (HR 1.23, 95%CI 1.21-1.26), hypotension (HR 1.32, 95%CI 1.29-1.35), syncope (HR 1.20, 95%CI 1.17-1.22), AKI (HR 1.44, 95%CI 1.41-1.47), electrolyte abnormalities (HR 1.42, 95%CI 1.43-1.48) and gout (HR 1.35, 95%CI 1.32-1.37). The absolute risk of SAEs with treatment was very low, with four fall events per 10,000 patients treated per year. In older patients (80-89 years) and those with severe frailty, this risk was increased, with 53 and 62 fall events per 10,000 patients treated per year (respectively).

Consequences

Antihypertensive treatment is associated with SAEs, but the absolute risk of harm is very low. However, in older patients and those with severe frailty, this absolute risk is increased and physicians should take this into consideration when making prescribing decisions.

Submitted by:

James Sheppard

Funding acknowledgement:

This study was funded by the Wellcome Trust, Royal Society, National Institute for Health Research