Clinical Question

Are there any medications that can prevent or delay cognitive decline, cognitive impairment, or dementia?

Bottom Line

None of the medications in this systematic review prevented or delayed cognitive decline, cognitive impairment, or dementia. (Level of Evidence = 1a–)

Synopsis

These researchers searched four databases, including the Cochrane Library, to identify randomized and nonrandomized controlled trials in English that enrolled adults without dementia. They also searched reference lists of previous studies and included a previous report that evaluated interventions to prevent cognitive decline. Two reviewers evaluated the quality of the studies, and one reviewer extracted the data from the studies, which were checked by another reviewer. This wide-ranging review identified three studies of acetylcholinesterase inhibitors, although most of the impact was from a single study of donepezil (Aricept) in 512 patients with preexisting cognitive deficit. After three years, active treatment did not affect the progression to Alzheimer disease, nor did it affect any cognitive test result as compared with placebo. Other treatments were also ineffective, including antihypertensives, diabetes medication, lipid-lowering medication, nonsteroidal anti-inflammatory drugs, and testosterone. Estrogen alone or with progestin increased the risk of dementia in one low-quality trial. High-dose raloxifene (Evista), but not the usual dosage of 60 mg daily, decreased the likelihood of developing mild cognitive impairment, but not dementia, in a single study (low-quality evidence).

Study design: Meta-analysis (randomized controlled trials)

Funding source: Government

Setting: Various (meta-analysis)

Reference:FinkHAJutkowitzEMcCartenRet alPharmacologic interventions to prevent cognitive decline, mild cognitive impairment, and clinical Alzheimer-type dementia: a systematic review. Ann Intern Med2018;168(1):39–51.