Fatigue in myotonic dystrophy type 1: a seven-year prospective study.

OBJECTIVES: Cross-sectional studies reported fatigue in 50-90% of patients with myotonic dystrophy type 1 (DM1). The aim of this research was to assess frequency of fatigue in DM1 patients during a seven-year period. MATERIALS AND METHODS: Study included 64 DM1 patients at baseline (50% males, age 42 ± 12 years), and 38 after seven years. Following scales were used: Muscular Impairment Rating Scale (MIRS), Fatigue Severity Scale (FSS, score equal to or greater than 36 indicates significant fatigue), and Daytime Sleepiness Scale (DSS, score of more than six is considered significant). RESULTS: At baseline, 54% of DM1 patients had fatigue and 46% had excessive daytime sleepiness (EDS). Ten (32%) patients with fatigue had no EDS. At the baseline, patients with fatigue were older, were more likely to had adult-onset DM1, worse MIRS and DSS compared to the patients without fatigue. After seven years, FSS score increased (34 ± 15 vs 48 14, p < 0.01), fatigue was found in 82% of patients, and EDS in 60%. Still eight (26%) patients with fatigue had no EDS. Fatigue progression did not parallel MIRS increase. CONCLUSIONS: Fatigue is a common symptom of DM1 and its progression during time did not correlate with the progression of muscle weakness.

Personality traits in patients with myotonic dystrophy type 2.

Myotonic dystrophy type 2 (DM2) is a multisystem disorder that affects many organs and systems, including the brain. The objective is to analyze personality patterns in myotonic dystrophy type 2 (DM2) compared to DM1 control group. The study comprised 27 consecutive genetically confirmed DM2 patients and control group of 44 DM1 patients. Personality traits were assessed with the Millon Multiaxial Clinical Inventory III (MMCI III). In DM2 group there were no scale with pathological scores, although compulsive and paranoid traits were the most prominent. DM2 patients had lower scores compared to DM1 patients in almost all scales. Pathological scores on clinical symptom scales were not observed, although anxiety scale almost approached this value. Patients with higher compulsive score had higher level of education (rho = +0.53, p < 0.01). On the other hand, higher paranoid score correlated with younger age at onset (rho = -0.34, p < 0.01) and lower educational level (rho = -0.26, p < 0.05). Our results did not show significant personality impairments in patients with DM2. However, following personality traits were predominant: compulsive (in patients with higher education) and paranoid (in patients with lower education and earlier age at onset). The most common clinical symptoms were anxiety and somatization.

Routine echocardiography in patients with myotonic dystrophy type 1.

BACKGROUND: Myotonic dystrophy type 1 (DM1) is an autosomal-dominant disease. One third of DM1 patients die suddenly, most of them due to the heart conduction abnormalities and arrhythmias. The aim of this study was to analyze echocardiographic findings in a large cohort of DM1 patients. METHODS: This retrospective study comprised 111 patients and 71 healthy controls (HCs) matched for gender and age. RESULTS: Mitral valve (MV) prolapse was observed in 23% of our DM1 patients vs. 8.5% of HCs (p < 0.05). Left ventricle (LV) systolic dysfunction was observed in 6% of patients and none of the HCs (p < 0.05). Frequency of diastolic dysfunction showed no significant difference between DM1 patients and HCs (8.1% vs. 15.5%, p > 0.05). Systolic dysfunction was more common in patients with severe electrocardiographic (ECG) abnormality (18.8% vs. 2.7%, p < 0.01). CONCLUSION: One fourth of DM1 patients have MV prolapse. Approximately 15% of DM1 patients have systolic or diastolic LV dysfunction. These patients should have benefit from medical therapy. Furthermore, it seems that treatment of conduction defects might prevent development of the heart failure (HF).

Quality of life in patients with myotonic dystrophy type 2.

AIM: To analyze quality of life (QoL) in a large cohort of myotonic dystrophy type 2 (DM2) patients in comparison to DM1 control group using both generic and disease specific questionnaires. In addition, we intended to identify different factors that might affect QoL of DM2 subjects. PATIENTS AND METHOD: 49 DM2 patients were compared with 42 adult-onset DM1 patients. Patients completed SF-36 questionnaire and individualized neuromuscular quality of life questionnaire (INQoL). Following measures were also included: Medical Research Council 0-5 point scale for muscle strength, Addenbrooke's cognitive examination revised for cognitive status, Hamilton rating scale for depression, Krupp's fatigue severity scale and daytime sleepiness scale (DSS) RESULTS: SF-36 total score and physical composite score did not differ between DM1 and DM2 patients (p>0.05). However, role emotional and mental composite score were better in DM2 (p<0.05). INQoL total score was similar in both groups (p>0.05), although DM2 patients showed less impairment in independence (p<0.05) and body image domains (p<0.01). Regarding symptoms assessed by INQoL, DM2 patients showed less severe complaint of myotonia (p<0.01). Multiple linear regression analysis showed that significant predictors of worse QoL in DM2 patients were older age, worse muscle strength and higher level of fatigue. CONCLUSION: QoL reports of DM2 patients with the most severe form of the disease are comparable to those of DM1 patients. Special attention of clinicians should be paid to DM2 patients with older age, more severe muscle weakness and higher level of fatigue since they may be at higher risk to have worse QoL.

Cardiologic predictors of sudden death in patients with myotonic dystrophy type 1.

The aim of this study was to analyze survival, causes of death and cardiologic predictors of sudden death in a large cohort of patients with myotonic dystrophy type 1 (DM1). The study was comprised of 171 adult DM1 patients hospitalized at the Neurology Clinic in a 20-year period. Severe electrocardiographic (ECG) abnormality included at least one of the following: rhythm other than sinus, PR interval of ≥240 ms, QRS complex duration of 120 ms or more, and second-degree or third-degree atrioventricular (AV) block. Survival data were analyzed by the Kaplan-Meier test, log-rank test and Cox regression analysis. During the mean follow-up period of 9.4±5.4 years, a pacemaker was implanted in 5.8% of DM1 patients and 14% of patients died. The mean age at death was 55.6±12.5 years. The most common causes of death in our cohort were sudden death (41.7%) and respiratory failure (29.2%). The presence of palpitations (hazard ratio [HR]=4.7, p<0.05) and increased systolic blood pressure (HR=9.8, p<0.05) were significant predictors of sudden death. Among ECG parameters, severe ECG abnormality (HR=4.7, p<0.05), right bundle branch block (RBBB; HR=3.9, p<0.05) and bifascicular block (HR=5.8, p<0.05) were significant predictors of sudden death.