Relationship between cognitive impairment and serum amyloid β-protein, adiponectin, and C-reactive protein levels in type II diabetes patients.

Background: This study sought to explore the plausible mechanism of the cognitive impairment of patients with type 2 diabetes by analyzing the levels of serum amyloid β-protein (Aβl-42), adiponectin, and C-reactive protein (CRP).

Methods: Eighty-four patients diagnosed with type 2 diabetes and 60 healthy people were selected as the participants for this study. Clinical data were collected using self-made questionnaires. The Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) scale was used to access cognitive functions. The serum Aβl-42 and adiponectin levels were individually determined by an enzyme-linked immunoassay (ELISA). CRP was detected using a Siemens BNP II specific-protein analyzer.

Results: Patients in the case group had significantly lower immediate memory, visual span, speech function, attention, and delayed memory scores on the RBANS scale than patients in the control group. The Aβl-42 levels of patients in case group were significantly higher than those of patients in the control group. The age of patients was significantly negatively correlated to RBANS scale subtest scores and standard scores in the case group. The number of years of schooling was significantly positively correlated to immediate memory, visual span, attention, delayed memory scores, and standard scores, but negatively correlated with speech function. After adjusting for age and the number of years of schooling, the Aβl-42 levels of patients in the case group were significantly negatively correlated with immediate memory, attention, delayed memory scores, and standard scores (P<0.05). The adiponectin levels of patients in the case group were positively correlated with RBANS scale subtest scores and standard scores (P<0.05).

Conclusions: Type 2 diabetes patients suffered from cognitive impairment. It appears that the mechanism may be associated with increased serum Aβl-42 levels, decreased adiponectin levels and inflammation reaction. The detection of serum Aβl-42 and adiponectin could be used as indicators of the degree of cognitive impairment in patients with type 2 diabetes.