Initial postural hypotension risk with antidepressant use in older patients

By Dr Emily Lathlean MB BS, FRACGP

Analysis of UK primary care data has found a substantially increased risk of postural hypotension in older patients prescribed antidepressants during the first month of exposure.

The self-controlled case series study, published in the British Journal of General Practice, obtained data from more than 41,000 adults aged 60 years and older with incident postural hypotension between 2000 and 2018. About one-fifth (22%) of participants had been prescribed a selective serotonin reuptake inhibitor (SSRI), one-fifth had been prescribed a tricyclic antidepressant (TCA) and 11% had been prescribed an ‘other antidepressant’.

All antidepressants were associated with a consistent increased risk of postural hypotension during the first 28 days of exposure, particularly SSRIs, followed by ‘other antidepressants’ and then TCAs. The risk of postural hypotension reduced from day 28 onwards for all antidepressants.

‘This is an important study as there have been very few reports of adverse effects of antidepressants in a large elderly general practice population,’ said Professor Philip Mitchell AM, Scientia Professor in the Discipline of Psychiatry and Mental Health at UNSW Sydney.

The researchers emphasised that postural hypotension was a common issue in older people that could be associated with serious complications, and noted that although it had been described as an adverse effect of antidepressants in previous studies with limitations, it was rarely recognised in practice.

‘While clinicians are aware of the potential for postural hypotension with TCAs, this is usually not considered likely in those on other antidepressants, particularly SSRIs,’ Professor Mitchell said. ‘A possible explanation for the findings of high rates of postural hypotension in those on SSRIs may be found in the already greater rates of postural hypotension in the three months before prescription, suggesting that the SSRIs may be being used in a more physically frail population.’

Professor Mitchell said that the study findings should alert clinicians to carefully monitor for postural hypotension during the first month of prescription of any antidepressant in older patients.

Br J Gen Pract 2025; doi: https://doi.org/10.3399/BJGP.2024.0429.