Abstract
Objective: Diabetes Mellitus is associated with a higher incidence of neurobehavioral symptoms, inordinate fatigue, and cognitive impairment. The protein known as visfatin which is present in fat cells has been reported to have a direct association with Type 2 diabetes mellitus (T2DM) and neuroinflanunation. Therefore, the aim of this study is to ascertain whether or not there is a correlation in teens of cognitive function with visfatin levels in patients with T2DM in relation to body composition indices.
Method: Sixty five participants (31 of whom suffer from T2DM along with 34 control subjects) were recruited from outpatient clinics for the purpose of this observational case-control study. Clinical and demographic characteristics were measured for each participant and these were then matched according to the Fatigue Severity Scale (FSS) and the Visual Analogue Fatigue Scale (VAFS), both of which were used as screening tests before the neurocognitive assessment procedure commenced. s. Cognition was assessed by using the following tests; a Stop Signal Task (SST) test, an Intra-Extra Dimensional Set Shift (LED) test and a Spatial Span (SSP) test using a Cambridge Neuropsychological Automated Battery (CANTAB). Blood samples were then collected in order to measure levels of both visfatin and glycosylated hemoglobin (HbA1c). Body composition was analyzed using a Bio Impedance Analyzer (BIA).
Results: Cognitive impairments in the form of longer reaction times and impaired spatial planning were detected in T2DM study subjects. The SST Stop Signal Reaction Time (SST SSRT) (p=0.03), IED errors (p=0.0412), as well as the SST Direction Errors during STOP and GO trials (p=0.0431) were significantly delayed in T2DM subjects versus control subjects. Moreover, the SSP length was significantly lower in T2DM participants indicating an impaired working memory capacity (p=0.0209). By using a general linear model, the degree of hyperglycemia was found to be independently predictive of impulse control. Visceral fat was also found to be significantly correlated with the total proportion of IED errors (r=0.333, p=0.0412).
Conclusions: The results of this study show that T2DM patients have impaired cognitive functions in terms of flexibility of impulse control, attention span, and working memory capacity. Moreover, the degree of hyperglycemia may be independently predictive of impulse control in these subjects.