Instrumental activities of daily living in adults with the DM1 childhood phenotype: going beyond motor impairments.

Myotonic dystrophy type 1 (DM1) is the most common muscular dystrophy among adults. This cross-sectional study documents the level of independence in the instrumental activities of daily living (IADL) and explores the impact of executive functions and apathy on IADL accomplishment level among adults with the childhood phenotype of DM1. IADL accomplishment level was assessed with the Independent Living Scale (ILS) and the Activities of Daily Living Profile (ADL Profile). The later considered four operations related to executive functions: formulating a goal, planning, carrying out the task and goal attainment. Thirty-three individuals (19 females; mean age 39y, standard deviation 10y 6mo; range 23-57y) were recruited. According to the ILS total score, half of the participants were categorised as dependent. In financial management, no participant obtained the minimal score for independence. In the ADL Profile, higher dependence levels were frequent in IADL. Formulating a goal was the most difficult operation. Dependence level was more frequent in participants with apathy. Adults with the childhood phenotype exhibit significant difficulties in IADL accomplishment, especially considering their age. High levels of dependency observed with both outcome measures highlight their need for services to achieve optimal living conditions.