Disability and quality of life in Charcot-Marie-Tooth disease type 1.

OBJECTIVES Charcot-Marie-Tooth disease type I (CMT1) is a hereditary sensorimotor neuropathy causing variable degrees of handicap. The risk for relevant disability in respect to genetic counselling is unknown. An attempt was made to define it. METHODS Disability and ambulation of 50 patients with CMT1 were scored by the Hauser ambulation index score and the Rankin scale. Rankin score 2 was subdivided into 2a (independent without relevant slowness) and 2b (independent, though at the cost of excessive time consumption). The sickness impact profile was assessed and compared with patients 6 months after stroke who were without mental deficit. To define at which degree sickness and disability become relevant for genetic counselling, the patients were asked whether they would refrain from childbearing if the children were at risk of inheriting a disease that caused as much disability as they experienced themselves. RESULTS Subdivision of Rankin score 2 was reliable and improved validity. High disability significantly predicted an attitude against childbearing (stepwise logistic regression) only with this subdivision. Thirty six per cent of the patients voted against childbearing. The cut off for relevant disability in respect to childbearing was a Rankin score higher than 2a, which was present in 44% of the patients. Psychosocial impact was comparable with patients with stroke and similar disability. Depression was present in 18% of the patients. CONCLUSION Subdivision of Rankin score 2 is recommended for the assessment of longstanding disability in neuromuscular disorders. Disability becomes relevant for the attitude towards childbearing as soon as everyday activities become markedly slow (Rankin score 2b). Relevant disability occurred in 44% of the patients. Emotional stress in CMT is similar to that of patients with stroke and comparable disability.