25-hydroxyvitamin-d-2 and Polyneuropathies

To quantify muscle strength and size in subjects with impaired glucose tolerance (IGT) in relation to intramuscular non-contractile tissue, the severity of neuropathy and vitamin D level.. A total of 20 subjects with impaired glucose tolerance and 20 control subjects underwent assessment of strength and size of knee extensor, flexor and ankle plantar and dorsi-flexor muscles, as well as quantification of intramuscular non-contractile tissue and detailed assessment of neuropathy and serum 25-hydroxy vitamin D levels.. In subjects with impaired glucose tolerance, proximal knee extensor strength (P = 0.17) and volume (P = 0.77), and knee flexor volume (P = 0.97) did not differ from those in control subjects. Ankle plantar flexor strength was significantly lower (P = 0.04) in the subjects with impaired glucose tolerance, with no difference in ankle plantar flexor (P = 0.62) or dorsiflexor volume (P = 0.06) between groups. Intramuscular non-contractile tissue level was significantly higher in the ankle plantar flexors and dorsiflexors (P = 0.03) of subjects with impaired glucose tolerance compared with control subjects, and it correlated with the severity of neuropathy. Ankle plantar flexor muscle strength correlated significantly with corneal nerve fibre density (r = 0.53; P = 0.01), a sensitive measure of small fibre neuropathy, and was significantly lower in subjects with vitamin D deficiency (P = 0.02).. People with impaired glucose tolerance have a significant reduction in distal but not proximal leg muscle strength, which is not associated with muscle atrophy, but with increased distal intramuscular non-contractile tissue, small fibre neuropathy and vitamin D deficiency.

Topics: 25-Hydroxyvitamin D 2; Adiposity; Aged; Ankle; Calcifediol; Early Diagnosis; Female; Glucose Intolerance; Humans; Knee; Leg; Lipid Metabolism; Magnetic Resonance Imaging; Male; Middle Aged; Muscle Strength; Muscle Weakness; Muscle, Skeletal; Polyneuropathies; Severity of Illness Index; Small Fiber Neuropathy; Vitamin D Deficiency