Charcot-Marie-Tooth Disease Type 1A: Influence of Body Mass Index on Nerve Conduction Studies and on the Charcot-Marie-Tooth Examination Score.

PURPOSE: Charcot-Marie-Tooth Disease type 1A (CMT1A) is caused by a duplication of the peripheral myelin protein gene 22 at chromosome 17p11.2-12. There is limited data regarding whether body mass index (BMI) affects electrophysiological or clinical data in those with CMT1A.
METHODS: Electrophysiological data, the Charcot-Marie-Tooth examination score (CMTES) and BMI from 101 patients with known CMT1A were obtained and analyzed.
RESULTS: When controlling for age, a higher BMI does not affect ulnar motor nerve conduction studies in those with CMT1A, but rather components of the CMTES (loss of pinprick and motor strength in the lower extremities).
CONCLUSIONS: BMI and clinical components of the CMTES are correlated, but it is uncertain which came first-whether the loss of lower extremity pinprick sensation and motor strength results in a higher BMI or if higher BMI results in these signs.