OBJECTIVES: To identify the factors that can potentially affect the ability of electrodiagnostic tests such as sural/radial amplitude ratio or SRAR and the presence of carpal tunnel syndrome or CTS to detect early subclinical neuropathy in diabetes mellitus (DM). Likewise, to investigate the likelihood of developing subclinical neuropathy that can be detected by a positive CTS or SRAR abnormalities, because of the presence of anthropometric factors and sugar levels, in addition to DM duration
METHODOLOGY: A retrospective cohort study was undertaken among 144 DM type 2 patients with confirmed subclinical neuropathy. Demographic data such as age, height and age, body mass index (BMI) and blood glucose profiles were obtained. Nerve conduction findings (SRAR and CTS protocols) were statistically analyzed using two sample t-test and multiple logistic regression ratios
RESULTS: Patients who were positive in the CTS protocols were taller and had lower BMI. They had shorter duration of DM but with extreme elevations in blood glucose. Variables that are independently associated with a (+) CTS are duration of DM, FBS, BMI, height and weight. Patients with SRAR abnormalities were older and obese, with longer duration of DM and less marked elevations in blood glucose. Variables that are independently associated with SRAR abnormalities are age, duration of DM, weight and BMI
CONCLUSION: Factors such as age, duration of DM, weight and height, BMI as well as glucose control can potentially affect the ability of various electrodiagnostic tests (SRAR and the presence of CTS) to detect early subclinical neuropathy. Since confounding factors was different between CTS and SRAR, the pathogenesis of these conditions may be different. The likelihood of developing subclinical neuropathy that can be detected by a (+) CTS or SRAR abnormalities because of the presence of certain factors, were documented.