Age Related Burden of Swallowing in Adult Patients Affected by Duchenne Muscular Dystrophy.

BACKGROUND: In Duchenne muscular dystrophy (DMD), dysphagia is a common but often overlooked symptom, which may affect quality of life (QoL). Its possible causes are progressive deterioration of muscle groups involved in swallowing function (oropharyngeal, inspiratory muscles) or impairment of autonomic function. OBJECTIVES: In adult patients with DMD, we aimed to identify predictors of swallowing-related QoL and to compare swallowing-related QoL at different ages. METHODS: Forty-eight patients aged 30.0±6.6 years were enrolled. Questionnaires were administered: the Swallowing Quality of Life questionnaire (SWAL-QOL) for swallowing-related QoL assessment, and the Compass 31 for autonomic symptoms assessment. The Brooke Upper Extremity Scale was used for upper limbs muscular function assessment. Respiratory and muscle function tests were performed, including spirometry, arterial blood gases, polysomnography, maximal inspiratory pressure (MIP), maximal expiratory pressure and sniff nasal inspiratory pressure. RESULTS: An abnormal composite SWAL-QOL score (≤86) was found in 33 patients. Autonomic symptoms were mild, while a severe impairment was shown by the Brooke Upper Extremity Scale. Spirometry and muscle strength tests demonstrated severe alterations, while diurnal and nocturnal blood gases were normal, due to effective use of noninvasive ventilation. Independent predictors of the composite SWAL-QOL score were age, MIP and Compass 31. A MIP < 22 had an accuracy of 92% in predicting altered swallowing-related QoL. The composite SWAL-QOL score was worse in subjects > 30 years old than in younger patients (64.5±19.2 vs 76.6±16.3, p < 0.02), due to worse scores in items pertinent to mental and social functioning; scores in domains pertinent to the physical function were similar in both groups. CONCLUSIONS: In adult DMD, swallowing-related QoL, which is altered in most patients, can be predicted by age, inspiratory muscles strength and autonomic dysfunction symptoms. While swallowing function is already altered in young patients, swallowing-related QoL can progressively worsen with advancing age due to psychological and social factors.

Cardiovascular autonomic control during application of different modes of noninvasive ventilation in patients affected by amyotrophic lateral sclerosis.

BACKGROUND: Cardiovascular events commonly cause death in amyotrophic lateral sclerosis (ALS) even in patients treated by noninvasive ventilation (NIV). OBJECTIVES: to evaluate autonomic function with the assessment of heart rate variability (HRV) in ALS patients treated by assist pressure control ventilation (APCV) and assist control ventilation (ACV) during sleep. METHODS: Consecutive ALS patients underwent one polysomnography during APCV and one during ACV. HRV was analyzed both in the total sleep period (from first stage N1 to last awakening) and in a 5-minute period of stable stage N2. Time domain, frequency domain and nonlinear indexes of HRV were measured. RESULTS: Nineteen patients (age 62.0 ± 8.7, 9F/10 M) were studied. The analysis did not reveal differences in blood gasses between NIV modalities, but a longer expiratory time (3.01±0.6 vs 2.8 ± 0.6 s, respectively APCV vs ACV, p = 0.001) and a lower arousal index (17.5 ± 9.1 vs 23.1 ± 13.9, p = 0.02) during APCV. HRV was indicative of higher vagal activity during APCV, especially in the 5-minute periods. In the total sleep periods, the HRV time domain indexes reflecting parasympathetic activity were positively correlated with the expiratory time and negatively with the inspiratory/expiratory time ratio. Low frequencies were positively, and high frequencies negatively, correlated with inspiratory time. HRV and sleep structure parameters were not correlated, except very low frequencies that were correlated to the arousal index. CONCLUSIONS: Respiratory influences on autonomic control can be preserved in ALS. The slower breathing pattern during APCV may help to maintain a higher vagal activity. Through this mechanism, in the long-term APCV could more beneficial to ALS patients than ACV.

Short-Term Effects of Pressure Controlled Versus Volume Controlled Noninvasive Ventilation in Subjects With Amyotrophic Lateral Sclerosis.

BACKGROUND: Comparison of the effects of pressure controlled and volume controlled noninvasive ventilations (NIV) has usually been limited to the degree of improvement in blood gases. We compared sleep quality, abnormal respiratory events, and patient-ventilator asynchronies during administration of pressure controlled continuous mandatory ventilation (PC-CMV) and volume controlled continuous mandatory ventilation (VC-CMV) in subjects with amyotrophic lateral sclerosis naive to NIV after titration aimed at maximally improving nocturnal arterial blood gases. METHODS: A crossover evaluation of PC-CMV and VC-CMV was performed in 27 subjects with amyotrophic lateral sclerosis. After baseline polysomnography, ventilators were set in random order so as to warrant similar and satisfactory oxygen saturation and transcutaneous [Formula: see text] in both NIV modalities during day and night. Soon after titration, polysomnography was repeated during administration of each type of NIV. RESULTS: With respect to the baseline night, non-rapid eye movement 3, and rapid eye movement sleep stages increased, and the arousal index decreased during PC-CMV (P = .005, P = .02, and P = .01, PC-CMV vs VC-CMV, respectively) but not during VC-CMV. The arousal index during NIV was correlated to the peak pressure delivered by the ventilators (ρ = 0.47, P < .001). Few abnormal respiratory events were observed in both NIV modes. Patient-ventilator asynchronies were more frequent during VC-CMV (median [IQR] 20.8 [0.0 - 22.0] vs 31.8 [30.1 - 34.0] no./h, PC-CMV vs VC-CMV; P = .002). Twenty-one subjects declared that they preferred PC-CMV therapy. CONCLUSIONS: In the short term, PC-CMV may be a preferred NIV modality to VC-CMV for patients with amyotrophic lateral sclerosis, even when both NIV modes are similarly effective in the correction of hypoventilation. Evaluation of the effectiveness of NIV should not be limited to the assessment of blood gas correction.

Subjective sleep quality in adult patients affected by Duchenne muscular dystrophy. Beyond nocturnal hypoventilation.

OBJECTIVE: In stable neuromuscular patients under long-term non-invasive ventilation (NIV), subjective sleep quality may be predicted by chronic hypoventilation, as assessed by base excess (BE), and %N3 sleep stage duration. In this study, we explored how other variables, closely associated with self-reported health complaints, contributed to subjective sleep quality in adult patients with Duchenne muscular dystrophy (DMD). METHODS: This is a secondary analysis of a quality of life study in 48 adult DMD patients under NIV therapy, with little evidence of residual hypoventilation. Subjective sleep quality was evaluated by the Pittsburgh Sleep Quality Index (PSQI). A PSQI score >5 was considered indicative of poor sleep quality. Several other symptoms were evaluated: sleepiness, by the Epworth Sleepiness Scale (ESS); depression and anxiety, by the anxiety and depression subscales of the Hospital Anxiety and Depression Scale (HADS-A and HADS-D); autonomic symptoms, by the Composite Autonomic Symptom Score 31; pain, by the Numeric Pain Rating Scale (NPRS); and fatigue, by the Fatigue Severity Scale (FSS). RESULTS: Mean PSQI was 6.1 ± 2.9. Abnormal scores were found for NPRS in 40, for HADS-A in 10 and for FSS in 24 subjects. The NPRS, HADS-A and FSS scores and the N3 sleep stage, independently predicted PSQI (R2 = 0.47, p < 0.0001). CONCLUSIONS: In adult DMD patients, pain, fatigue and anxiety may have a prominent influence on subjective sleep quality. Improvement of sleep quality may be of utmost importance in DMD, as it may ameliorate quality of life and extend its benefits to cardiovascular morbidity and life expectancy.