Question
What is the difference between subjective cognitive decline (SCD) and mild cognitive impairment (MCI)?
Answer
Normal aging involves changes in processing speed and working memory that do not interfere with daily function. Subjective cognitive decline (SCD) occurs when an individual reports perceived cognitive changes despite normal objective performance. Previously dismissed as "the worried well," SCD research now shows it can represent the earliest stages of neurodegeneration in some individuals (Jessen et al., 2020).
MCI is distinguished from SCD by objective impairment on standardized testing. Per Petersen et al.'s (2018) guideline update, the three diagnostic criteria are: subjective concern about cognitive changes (from the patient or an informant); objective impairment, typically 1.0–1.5 standard deviations below the mean; and preserved activities of daily living. When ADLs are significantly affected, the diagnosis shifts to dementia.
Jessen and colleagues (2020) introduced the SCD-Plus framework to identify features within the SCD population that increase the likelihood of progression to MCI and dementia. The six features are: a subjective memory complaint (specific to memory, not general cognition); onset within the past 5 years; age over 60; a high level of personal concern; informant confirmation; and minor neurological signs. Not all must be present, but the more that are, the greater the clinical concern.
This framework matters clinically because it moves you beyond the binary of "screen passed" or "screen failed." A patient who reports memory concerns with informant confirmation and a recent onset may meet SCD-Plus criteria even without objective impairment, which changes your clinical recommendation entirely.
This Ask the Expert is an edited excerpt from the course, What the Score Doesn't Tell You: Clinical Reasoning in Mild Cognitive Impairment, presented by Farzana Vela, MS, CCC-SLP, BSRC, RRT-NPS.
Continued and its subsidiaries provide professional education authored by qualified Subject Matter Experts for continuing education purposes. These materials are intended for educational purposes and do not constitute medical advice or a substitute for individual clinical judgment. Continued is not a clinical healthcare provider; the licensed professional is solely responsible for ensuring that the application of any techniques or information presented is within their legal scope of practice and jurisdictional requirements.
