A Meta-Analysis of Cognitive Functioning in Nondemented Adults with Type 2 Diabetes Mellitus

Abstract

Type 2 diabetes leads to mild to moderate deficits in all measured cognitive abilities. There was a lack of published studies investigating type 2 diabetes-associated variables; therefore, additional meta-analyses investigating the impact of these variables on cognitive functioning in type 2 diabetes could not be performed. As such, data from individual studies must be reported consistently to allow for investigation of variables that may affect the relationship between type 2 diabetes and cognitive functioning. Given the present findings, clinicians working with patients with type 2 diabetes should be alerted to the possibility of cognitive changes that could impact type 2 diabetes treatment management or require referral for neuropsychological assessment.

Diabetes mellitus is independently associated with more severe cognitive impairment in Parkinson disease

“…The largest effect sizes were found for attention and processing speeds (26). Our findings in PD-DM subjects also showed the greatest impairments in attentional function, followed by executive function deficits.…”

“…A recent meta-analysis of cognitive functioning in non-demented adults with type II DM found that diabetic patients performed significantly lower than nondiabetic controls on all cognitive abilities evaluated, with effects size ranging from −0.14 to −0.37 (26). The largest effect sizes were found for attention and processing speeds (26).…”

Diabetes and Cognitive Impairment

“…Overall, the data shows a stronger association between dementia in T2DM than T1DM. Specifically, T2DM is associated with a 50 % increase in the risk for dementia [2] and has been associated with impaired attention, processing and motor speed, executive functioning, and verbal memory [1, 4••, 5]. Among the components of metabolic syndrome, hyperglycemia has the strongest association with the risk of developing cognitive impairment [6].…”

Association between intake of dairy products and short-term memory with and without adjustment for genetic and family environmental factors: A twin study

“…Previous longitudinal studies have shown that higher intake of dairy products was associated with lower risk of developing type 2 diabetes [35] and hypertension [36], and these conditions are reported to be potential risk factors for cognitive decline [37,38]. Specifically, under conditions of hypertension, and diabetes, high intake of dairy products may prevent cognitive decline [10].…”