Phrenic nerve conduction studies as a biomarker of XXXX in amyotrophic lateral sclerosis.

@entity1 @entity1353 @entity2655 @entity1576 @entity7404 @entity551
UNASSIGNED: Our objective was to examine the value of phrenic nerve conduction studies (PNCS) in quantifying diaphragm dysfunction in @entity2655 , as no ideal test of @entity1576 exists in @entity2655 . We prospectively recorded bilateral PNCS, forced vital capacity (FVC), @entity551 ( @entity551 ), sniff nasal inspiratory pressure (SNIP), respiratory rate, ALSFRS-R, and respiratory symptoms in 100 @entity2655 @entity1 attending our clinic over a nine-month period. Survival data were collected for two years. Results showed that PNCS were reproducible and well tolerated. When the @entity7404 was abnormal (<0.3 mV), the relative risk of a respiratory rate   >18 was 7.2 (95% CI 2.2-37.2, p   <0.01) compared with a @entity7404   >= 0.3 mV. Similarly, the relative risk of orthopnea was 3.5 (95% CI 1.6-8.7, p   <0.01) and @entity1353 2.4 (95% CI 1.4-4.0, p   <0.01). FVC had the strongest correlation with @entity7404 (R(2)   =   0.48 (p   <0.001)). Fourteen of 15 @entity1 with a FVC   <50% had a @entity7404   <0.3 mV. However, eight with a @entity7404   <0.3 had a FVC   >80%. The median survival was 1.07 years when the @entity7404 was   <0.3 mV and   >2 years when the @entity7404 was   >0.3 mV (p   <0.001). In conclusion, the phrenic @entity7404 correlated closely with multiple symptoms, signs, and laboratory measures of @entity1576 and may prove to be a useful biomarker of @entity1576 in @entity2655 .
