The clinical relevance of the use of age-, education- and sex- adjusted normative data for the Montreal Cognitive Assessment; a cohort study

Abstract

Background: Cognitive impairment is a major source of morbidity. The Montreal Cognitive Assessment (MoCA) is a validated screening instrument to assess cognitive performance. Recent literature introduced an age-, education- and sex-adjusted interpretation method to enhance clinical accuracy of the MoCA. However, its clinical applicability in brain injury patients is currently unknown. Objective: To evaluate the clinical relevance of the demographic-adjusted MoCA (DA-MoCA) interpretation to detect cognitive impairment among acquired brain injuries patients. Methods: We studied two brain injury cohorts. Firstly, a data analysis of the Restore4stroke Cohort (n=347) at 2 months post-stroke was performed. Secondly, a prospective cohort including 51 brain injury patients admitted at the University Medical Center Utrecht (UMCU) was studied. We compared cognitive impairment rates between the original- and DA-MoCA interpretation. Differences in patient characteristics in patients with opposite outcome were explored. Results: We compared cognitive impairment rates between the original- and DA-MoCA interpretation. According to the DA-MoCA cognitive impairment rates dropped by 19.8% (Restore4Stroke) and 7.8% (UMCU), and no participants were newly diagnosed as cognitively impaired. Participants reclassified as not cognitively impaired according to the DA-MoCA were characterized by significantly lower levels of education in the Restore4Stroke cohort and by older age in the clinical brain injury cohort (UMCU). Conclusion: The DA-MoCA interpretation reduces the number of participants diagnosed with cognitive impairment, primary by correcting for the influence of age and education on cognitive functioning. The DA-MoCA interpretation could particularly be relevant for populations characterized by extremes in age and education.