Prevalence and correlates of apathy in myotonic dystrophy type 1

Abstract

BackgroundApathy in DM1 has long been acknowledged in clinical practice. However, a major drawback is that the concept has been only sparsely explored in previous specific studies. This study aimed to determine the prevalence of apathy in myotonic dystrophy (DM1), to compare it with facioscapulohumeral dystrophy (FSHD) patients and normal healthy controls, and explore its relationship to psychopathological features and cognitive function.MethodsLevels of apathy in 38 DM1 patients with adult phenotypes were compared with 19 patients with FSHD and 20 matched controls. Patient participants were consecutively recruited, regarding their interdisciplinary annual evaluation at the neuromuscular pathology reference center (Institute of Myology, Paris, France), within an 18-month period. Additional measurements included motor disability, fatigue, depression, anxiety, and cognitive abilities. Inter-group comparisons were performed using non-parametric Kruskal-Wallis tests and Mann–Whitney U Tests. Intra-group comparisons were carried out with the Wilcoxon Signed rank and Friedman tests. Also, Spearman’s correlations were used to assess the strength of linear relationships between pairs of variables. The significance level was set at 0.05.ResultsGlobal score of apathy was significantly higher in DM1 patients than in FSHD patients (p < 0.01) and in controls (p < 0.001). Sixteen of 38 DM1 patients (39.5 %) met the criterion for apathy, contrasting with only 4 of the 19 (21.1 %) FSHD patients. No control subject was apathetic. Moreover, apathy in DM1 patients was negatively correlated to MMSE (r = −.46, p < .05) and Stroop Word (r = −.55, p < .01) scores, but not with age, educational level, disease duration, CTG repeats, motor functional disability, fatigue, depression, and anxiety.ConclusionsApathy is a frequent symptom in DM1 (almost 40 %). It is more prevalent than in a similarly disabled group of patients with FSHD and in controls. Results also show that apathy in DM1 is independent of the psychopathological domain, fatigue, age, and motor disability, but associated to general cognitive status. These results altogether could suggest a central cause for apathy in DM1 rather than an adjustment process to cope with the progressive and debilitating nature of the disease. Data emphasize the importance to evaluate this symptom in routine clinical management of DM1 patients.Electronic supplementary materialThe online version of this article (doi:10.1186/s12883-015-0401-6) contains supplementary material, which is available to authorized users.

Clinical neuropsychology in the management of myotonic dystrophy

“…Although their study included no controls for the impact of marked motor impairment, this finding adds to a body of work showing that many people with myotonic dystrophy type 1 have cognitive difficulties . Consistent with existing work, a significant proportion of participants in the sample recruited by Fujino et al . demonstrated comorbid behavioral symptoms/changes—with higher levels of apathy and depression apparent in the sample.…”

Disease awareness in myotonic dystrophy type 1: an observational cross-sectional study

“…Affective and depression-like symptoms are frequently observed in DM1 subjects, whereas only few patients fully match the criteria for a depressive disorder [ 16 , 23 ]. Lack of interest (apathetic behaviour), a decreased emotional participation and an increased irritability are common features, also defined as “an emotional imbalance” [ 24 , 25 ].…”

Intra-Rater Reliability and Concurrent Validity of Quantified Muscle Testing for Maximal Knee Extensors Strength in Men with Myotonic Dystrophy Type 1

“…While it is important that the participants are adequately stimulated throughout all populations, it is particularly important in DM1 since apathy is very frequent in this disease [6]. All of these factors, as well as a highly standardized technique should be respected while evaluating maximal muscle strength.…”

“…DM1 is a multisystemic disease, which affects cardiovascular, endocrine, neurological and musculoskeletal systems, to name a few [4]. Neurological affections can include cognitive impairments, daytime sleepiness and apathy [4][5][6]. Skeletal muscles are notably affected and patients with the disease experience slowly progressive muscle atrophy and weakness [4,7].…”