Reacción a "A study associates a type of antidepressant with accelerated cognitive decline in people with dementia"

This large population-level study from Sweden uses real-world data and is well-conducted. However, there are some important limitations that should be considered. One major issue is that the severity of depression in dementia patients wasn't fully accounted for, which has the potential to bias the results. Additionally, there may be a "channelling bias," meaning that certain antidepressants like citalopram and sertraline might have been more commonly prescribed to patients with severe dementia, which could also bias the results. 

“Another key limitation is that the study found only a small change in MMSE (Mini-Mental State Examination) scores, which may not be meaningful in everyday clinical practice. Previous research has shown that older adults taking tricyclic antidepressants can experience faster cognitive decline because these drugs interfere with the activity of acetylcholine—a chemical in our brain critical for maintaining cognition. Even among SSRIs (a common type of antidepressant), some, like paroxetine, are known to have stronger anticholinergic effects that could impact cognition negatively. There is also a problem of “residual confounding”,- meaning there could be other risk factors that can affect cognition, and it is unclear if they have accounted for other anticholinergic drugs like oxybutynin, which many dementia patients take to treat their urinary incontinence. The analyses were done on dispensed data (medication sold by pharmacists), and it is unclear if patients actually took them. 

“This study suggests that SSRIs like citalopram and sertraline might also speed up cognitive decline. However, it doesn’t explain how or why this happens at a biological level. Because of these limitations, the study's findings should be interpreted with caution and ideally replicated using other real-world data sources.