Chronoscopic reading in whole body reaction times can be a tool in detecting cognitive dysfunction in type 2 diabetics: a case control study

Abstract

Type 2 diabetes mellitus investigated as a risk factor for cognitive decline. It is known that the difference between simple and choice reaction time implies time required for cognition. Though delayed reaction times indicate involvement of cognition, they cannot quantify how much time is required for cognition. In whole body choice reaction time (WBCRT), reaction time is split into two chronoscopic readings: Chronoscopic reading-1 (C1) and chronoscopic reading-2 (C2). C1 measures time required for central processing that requires cognition and C2 measures the total reaction time. C2 — C1 measures time required for peripheral motor response. We hypothesized that WBCRT C1 will be delayed in diabetes and will have predictive value in detecting cognitive dysfunction. Settings and Design: Hospital- based case control study. Materials and Methods: Study was conducted on 120 subjects using visual and whole body reaction times having criteria of age (40-60 years) and diabetes, compared with equal number of age- and sex-matched controls. Statistical analysis was done by independent t-test and duration of diabetes was correlated with cognition times (WBCRT C1) using Pearson’s correlation. Predictive value of WBCRT C1 was calculated by using the receiver operating characteristic (ROC) curve. Results: WBCRT C1 (564 ± 107 ms) among diabetes patients was more delayed than WBCRT C1 (513 ± 86 ms) among controls indicating a cognitive dysfunction in patients with diabetes. There was no significant correlation between hemoglobin A1c (HbA1c) levels in patients with diabetes and diabetic duration with WBCRT C1. The best cutoff value for WBCRT C1, when predicting cognitive dysfunction in patients with diabetes, was 517 ms (sensitivity 50%, specificity 40%). Conclusions: WBCRT C1 can be used as a tool to detect cognitive dysfunction in patients with type 2 diabetes mellitus.