Evaluation of the effect of duration of diabetes mellitus on peripheral neuropathy using the United Kingdom screening test scoring system, bio-thesiometry and aesthesiometry

Abstract

Background and objectives: Risk factors predisposing to foot ulceration in diabetic subjects are multiple. Long duration of diabetes mellitus is a major risk factor, likewise peripheral neuropathy (PN), which globally, is recognized as the commonest risk factor for foot disease in diabetic subjects.

Objectives: To evaluate the effect of duration of diabetes mellitus on peripheral neuropathy using the United Kingdom Screening Test (UKST) Scoring System, Bio-thesiometry and Aesthesiometry, in Nigerian diabetic subjects without current or previous foot ulceration.

Subjects and methods: One hundred and twenty (120) diabetes mellitus (DM) subjects with and without symptoms of peripheral neuropathy receiving care at the medical outpatient department (MOPD) and the diabetic clinic of the Nnamdi Azikiwe University Teaching Hospital Nnewi, Nigeria, were recruited consecutively as they presented. Data collected included subjects age (years), gender, age at first diagnosis of DM, duration of DM (years) and baseline fasting venous plasma glucose. The United Kingdom Screening Test (UKST) symptom score was used to separate the participants into two groups those with symptoms of PN and those without and the subjects further assessed by three methods the UKST Signs score, Bio-thesiometry and Aesthesiometry to determine the presence . of PN.

Results: Among the 120 diabetic participants, 83(69.2%) had neuropathic symptoms (the symptomatic participants) while 37 (30.8%) were asymptomatic (the asymptomatic participants). The different methods of diagnosing PN increasingly detected PN with increasing duration of diabetes. For the symptomatic group, the UKST method detected PN least in those with duration of DM <5 years (73.9%) and 100.0% in those with duration of DM >15 years while for the asymptomatic group, it detected PN in 25.0% of those with duration of DM <5 years, and 100.0% for those with duration of DM >15 years. For the symptomatic group, Aesthesiometry detected PN in 65.2% of those with duration of DM <5 years and 91.7% in those with duration of DM >15 years. For the asymptomatic group, it detected PN in 29.2% of those with duration of DM <5 years and 100.0% in those with duration of DM >15 years. Likewise, for the symptomatic group, Bio-thesiometry detected PN in 47.8% of those with duration of DM <5 years and 100.0% in those with duration of DM >15 years. For the asymptomatic group, it detected PN in 16.7% of those with duration of DM <5 years and 100.0% in those with duration of DM >15 years.

Conclusion: Long duration of diabetes mellitus and peripheral neuropathy are risk factors for foot complication in Nigerians with diabetes mellitus. Diabetic subjects with long duration of diabetes (>10 years) almost always have associated peripheral neuropathy, and should be recognized as a special group at high risk for foot disease from DM. Specific preventive programs should target this group to reduce the rate of avoidable loss of limbs to diabetes.