REVIEW OF: Weinstein AM et al, Am J Geriatr Psychiatry 2022;30(1):54–64

STUDY TYPE: Cross-sectional study

When we want to screen an elderly patient for mild cognitive impairment (MCI), should we refer them to full-scale neuropsychological testing, or is it sufficient to use the Montreal Cognitive Assessment (MoCA), which we can do ourselves during an appointment? A recent study aimed to provide some guidance for this common clinical issue.

Researchers looked at baseline data from a study of older adults who had been enrolled in a large randomized controlled trial. These patients had a history of major depressive disorder in remission, MCI, or both. An unblinded group of experts attempted to compare diagnoses using two approaches. The first used “gold standard” neuropsychological testing; the second approach combined MoCA scores with DSM-5 criteria. The study sample included 431 older adults with a mean age of 71 years. The subjects were primarily White (78%), female (63%), and highly educated (74% had a four-year college degree). Mean baseline score on the Montgomery–Åsberg Depression Rating Scale was 3.7, and the average MoCA score was 24.7.

Although the researchers found moderate agreement between the two diagnostic approaches (p<0.0005), there was discrepancy in 103 cases (23.8%). In 91 of those cases, neuropsych testing reported more severe cognitive impairment than the MoCA. Diagnostic discrepancies were more likely to occur in patients with a history of a major depressive episode or ApoE4 carrier status, both established risk factors for cognitive decline. Study limitations included small sample size, lack of blinding, and lack of generalizability.

Carlat Take

The majority of patients don’t need full-scale neuropsychological testing to screen for MCI. As the MoCA is now proprietary, clinicians may consider alternative options, such as the Saint Louis University Mental Status (SLUMS) examination. Although screening tools are quite helpful, the MoCA may miss almost a quarter of MCI cases, so neuropsych testing remains the gold standard. You might also consider a neuropsych referral when a patient has a history of depression or a family history of Alzheimer’s disease, or when a patient and their family members have highly disparate reports related to degree of impairment.