Factors Associated with a Positive Screen for Cognitive Impairment in Older People with Type 2 Diabetes in South Auckland

Abstract

The prevalence of type 2 diabetes is rising. Amongst its multiple effects it increases the risk of cognitive impairment in older adults. The thesis aims to (1) quantify the association of commonly measured clinical and social factors with a positive cognitive impairment screen (2) quantify the effect of English as second language on the Montreal Cognitive Assessment(MoCA) and Rowlands Universal Dementia Assessment(RUDAS) (3) estimate the prevalence of screen positive cognitive impairment in persons with diabetes aged 65-90. Methods Participants were aged 65-90. They were recruited from the diabetes outpatient services of a large health board in Auckland, New Zealand. The MoCA and/or RUDAS were administered to each participant to screen for cognitive impairment and data was collected on glycaemic, microvascular and macrovascular complications, metabolic, orthostatic hypotension, frailty, mood, medications and social factors. Results 96 participants were recruited. 82 did MoCA, 83 did RUDAS and 69 did both. On univariate analysis hypoglycaemia, retinopathy, peripheral neuropathy, orthostatic hypotension and frailty were associated with CI on both MoCA and RUDAS. Previous cerebrovascular accident, English as a second language and less years of schooling was associated with CI on MoCA but not RUDAS. On multivariate analysis retinopathy, cerebrovascular accident, language and schooling were associated with positive screen for MoCA while orthostatic hypotension and depression were associated with positive screen for RUDAS. Prevalence of screen positive for MoCA was 45.1% versus RUDAS of 16.8%. Conclusion There are specific clinical factors that are associated with increased risk of screen positive cognitive impairment in older persons with diabetes. The impact of English as a second language on the results of the cognitive screen warrants further investigation.