Nerve Conduction Study in Early Diagnosed Cases of Hypothyroidism in Central India

Abstract

Thyroid gland has multiple effects on the neuromuscular system and brain, its dysfunction is associated with characteristic symptoms and signs with functional alterations in many organs and systems. Thyroid disease may cause signs and symptoms of neuromuscular dysfunction. Hypothyroidism has been associated with the clinical features of proximal muscle weakness, mononeuropathy and sensorimotor polyneuropathy.Nerve conduction studies (NCS) are useful adjunct to the clinical examination of the peripheral nervous system as it is helpful to test speed of signals through a nerve. They help to delineate the extent and distribution of the neural lesion and distinguish two major categories of peripheral nerve disease demyelination and axonal degeneration. Present cross sectional studywas conducted at Central Neurophysiology Laboratory in tertiary care teaching hospital, J.N.M.C, Sawangi (M), Wardha catering to rural population of central India to assess the nerve conduction in early diagnosed hypothyroid patients. Total twenty seven patients; 20-50yrs of age were screened for nerve conduction.In our study we got mixed type of peripheral neuropathy. Out of 27 patients with age 18-30 yrs-1(16.67%), 31-40 yrs-13(61.90%) and 41-50 yrs -7 (33.3 %) had abnormal NCS. Occurrence of neuropathy was more common in female patients 80.95% as compared to male patients 19.05%.Sensory nerve action potential (SNAP) amplitudes and conduction velocity were significantly reduced (p<0.05) in cases diagnosed as hypothyroidism in median (77%), sural (70%) and ulnar nerves (33%)as compared to controls.