Written by Kevin Liu
Spoon Feed
For adults ≥60 years, antidepressant initiation was associated with postural hypotension for the first month, regardless of drug mechanism.
Antidepressants – good vibes, surprise posture-related dives
We know that falls are associated with antidepressant initiation, suspected to be due to polypharmacy, sedation, and anticholinergic side effects, but this study suggests another cause: postural hypotension.
In a self-controlled case series that included all patients in the UK between 2000-2018, 18 million patients ≥60 years old had first-time antidepressant initiation, with 41,005 (1.6%) having associated postural hypotension. All antidepressant drug classes were associated with an increased risk of postural hypotension. In the first 28 days of initiation, tricyclic antidepressants (TCA) exposure carried an increased relative risk (IRR) 2.12 (95%CI 1.79-2.50); serotonin selective reuptake inhibitors (SSRI) IRR 4.22 (95%CI 3.76-4.74); “other antidepressants” – serotonin norepinephrine reuptake inhibitors (SNRI) and mirtazapine – IRR 2.17 (95%CI 1.76-2.68). Importantly, of the three classes, SSRIs maintained a persistent IRR 1.62 (95%CI 1.50-1.77) even after 57 days of initiation. While the risk of postural hypotension is low (<1.6%) in the total population ≥60 who received antidepressants, it merits consideration whether or not a fall on an SSRI warrants a transition to another drug class. Because this is a case series study, we can only generate the hypothesis that SSRIs likely have a stronger association with falls in an older population; but it raises the important question of whether future guidelines will be revised to recommend SNRIs or other drug classes as first-line treatment for depression in the elderly.
How does this change my practice?
We see depression in 11.5% of hospitalized patients, and antidepressants are often initiated inpatient for patients with a prognosis of > 6 months. Prior to this study, postural hypotension was not a well-known side effect associated with antidepressant initiation. Falls have historically been a well-known side effect of SSRIs, SNRIs, and TCAs, but this study encourages me to more carefully engage with conversations about the harms of antidepressant initiation, especially in the first month of treatment, and to encourage SNRIs first line. Depression is debilitating, but so is having a fall.
Source
Antidepressants and risk of postural hypotension: a self-controlled case series study in UK primary care. Br J Gen Pract. 2025 May 19:BJGP.2024.0429. doi: 10.3399/BJGP.2024.0429. Epub ahead of print. PMID: 39824621
