Association between blood glucose control and mild cognitive impairment in patients with diabetes mellitus and small-artery occlusion

Abstract

Objective To study the association between blood glucose control and mild cognitive impairment (MCI) in patients with diabetes mellitus and small-artery occlusion (SAO). Methods A screening study of cognitive impairment was conducted in the 676 patients diagnosed with SAO who had been treated at Department of Neurology, Huanhu Hospital from January 2010 through June 2017. They were divided into a normal cognition group (n=629) and an MCI group (n=47) according to the screening results. They were also divided into 4 groups according to their history of diabetes and levels of hemoglobin A1c: normal blood glucose group (n=398), stringent goals group (n=59), general goals group (n=46) and goals-not-met group (n=173). The differences were compared in terms of Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment Scale (MoCA) scores between the normal blood glucose, stringent goals, general goals and goals-not-met groups. We also analyzed the general clinical data and risk factors between the normal cognition and MCI groups. Variables of confounders that were identified as significant were entered into logistic regression. Results There were significant differences in MMSE and MoCA scores between the 4 groups (P<0.05). Between the normal cognition and MCI groups, significant differences were found in proportion of smokers, blood glucose level and severity of stroke (P<0.05). Logistic regression analysis showed that compared with the normal blood glucose group the incidence of MCI was 2.707-fold higher in the stringent goals group (OR=2.707, 95% CI: 1.035~7.083, P=0.042), 2.963-fold higher in the general goals group (OR=2.963, 95% CI: 1.064~8.277, P=0.038) and 2.604-fold higher in the goals-not-met group (OR=2.604, 95% CI: 1.269~5.341, P=0.009). Conclusions MCI is more likely to occur in acute phase in patients with diabetes and SAO stroke. The patients can benefit from joint managements of diabetes, stroke and cognitive dysfunction in clinical practice. Key words: Stroke; Small-artery occlusion; Diabetes mellitus; Blood glucose control; Mild cognitive impairment