Estimation of Prevalence and Predictors of Sub-clinical Peripheral Neuropathy in Indian adolescents with Type-1 Diabetes: a Case-Control study

Abstract

Abstract Aims: Comparison of nerve conduction (NCS) parameters of adolescents with type-1 Diabetes (T1D) with controls. Assessment of sub-clinical peripheral neuropathy prevalence and predictors in Indian adolescents with T1D. Methods: Case-control study. Cases(n=120):10-19 years, T1D duration>2 years. Exclusion: Comorbidities, illnesses affecting nerve function. Controls(n=40):Healthy, age, sex-matched. Results: Mean age:15.1±3 years; diabetes duration:7±3.5 years, HbA1c:9.6±2.1% (81mmol/mol). None had symptoms/signs of peripheral neuropathy. Both groups were similar in anthropometry, physical activity. NCS comparison demonstrated significantly prolonged latency, reduced action potential duration and nerve conduction velocity (p<0.01) in motor nerves (median, ulnar, peroneal, tibial) in patients with T1D. Sensory action potential duration in median and ulnar nerves, and sural conduction velocity were significantly lesser in T1D (p<0.05). 70% had at least one abnormal NCS parameter. Sub-clinical neuropathy prevalence- demyelinating motor: upper limbs (UL)-5.8%, lower limbs (LL)-12.5%; demyelinating sensory:UL-52.5%, LL-5.0%; axonal motor:UL-19.2%, LL-10.8%; axonal sensory: UL-11.7%, LL-6.7%. Eight (6.6%) had stage-1a distal symmetrical polyneuropathy. Poor glycemic control (OR=2.0), reduced insulin sensitivity (OR=1.8), advancing age (OR=1.4), reduced iron intake (OR=0.8) were significant predictors of sub-clinical neuropathy. Conclusion: The prevalence of sub-clinical peripheral neuropathy in Indian adolescents with T1D was high, with the highest prevalence of sub-clinical neuropathy being noted in the upper limbs. Despite no symptoms, NCS parameters were adversely affected in T1D, highlighting the need for early NCS-based screening. Poor glycemic control, reduced insulin sensitivity, advancing age, reduced iron intake were predictors of sub-clinical neuropathy.