Muscle force, balance and falls in muscular impaired individuals with myotonic dystrophy type 1: A five-year prospective cohort study

Individuals with myotonic dystrophy type 1 (DM1) have progressive muscle weakness with gait and balance impairments. We explored prospectively the natural history of muscle force, gait, balance, balance confidence and walking ability in muscular affected individuals with DM1. After five years data from 43 individuals (m/f: 18/25) were analysed. All measures of balance showed statistically significant deterioration (p < 0.001) with averaged yearly loss of function by 3-4%. In the group as a whole, loss of muscle force was statistically significant in all lower limb muscles measured after five years: changes relative to baseline force were median -6% to -18%. For males muscle force loss was statistically significant in all leg muscles, but only in hip flexors for women. After five years 100% of the men had fallen during the previous year and 67% three times or more, in contrast only 60% of the women had fallen in the previous year and 36% three times or more. The proportion of individuals seeking medical care the previous year, after falling, was more than doubled after five years, albeit the number of falls had not changed. Awareness of this increased risk of falls is important for caregivers and patients. (C) 2014 Elsevier B.V. All rights reserved.