Effect of Physical Therapy and Yoga on Quality of Life in Children with Duchenne Muscular Dystrophy – A Randomised Comparative Study

Introduction

Duchenne Muscular Dystrophy (DMD) is considered as the commonest of myopathies, caused due to the mutation of dystrophin gene, and is progressive.¹ In this condition, necrosis of the muscle fibers which are replaced with adipose tissue is seen. It usually presents with a symmetrical pattern of muscle weakness, starting proximally at the shoulder, pelvic girdle and the trunk. By the age of five, the children with DMD demonstrate limitations in performing daily activities. Difficulty in stair climbing is reported between seven and thirteen years, progressing to a loss of ambulation at around the age of nine.²

Quality of Life (QOL) is an extremely important issue, particularly to patients with chronic, debilitating and terminal diseases that can hamper physical, psychological, and social well-being.³ It was identified that increased weightage was given to QOL than physical functioning by the parents of DMD children which is not much addressed by most of the physical therapists dealing with rehabilitation.⁴ This in fact may hamper the relationship between the family and the therapist causing a reduced quality of treatment deliverance and adherence to exercise protocols. The progressive nature of the disease makes the children experience social isolation and exclusion from peers due to the loss of ability to participate in the activities. The above-mentioned factors play a role in how these individuals and their caregivers perceive QOL for goal setting in rehabilitation. Evidence found no relationship of physical impairment or a need for non-invasive ventilation with QOL in patients with DMD.⁵ Upon consideration as an outcome for rehabilitation, QOL may be influenced based on physical activity, level of disability and the involvement of psychosocial factors leading to positive and negative consequences.⁶

Physical therapy is considered essential for patients with impaired mobility,⁷ which focuses on deformity prevention, prolonging ADL independence, facilitating movement, controlling discomfort, and educating the caregivers. Whereas yoga is a mind-body therapy, originated in ancient India, popularised and accepted globally for its health and therapeutic benefits. Benefits of yoga include improvements in motor control, ventilatory functions, subjective measures of wellbeing, as well as a reduction in depression and anxiety.^8,9 The QOL in this patient population has been found to be related with the physical functioning,^10,11 but the effects of the physical therapy or yoga interventions on QOL are least explored.

DMD, is a chronic progressive disabling condition leading to a reduction in the QOL of patients. Physiotherapist, who has a major role in the multidisciplinary care team, must incorporate interventions in a view to enhance the QOL of their patients. The investigators identified a paucity in the evidence reporting changes in QOL in patients with specific interventions. Identifying the importance of physical therapy and yoga in influencing QOL in this population helps the therapist in the planning and execution of specific strategies in order to determine potential exercise load thresholds to avoid injuries as well as to improve QOL. A home-based exercise regimen would be more cost-effective in the implementation and perhaps in ensuring better and longer participation from the patients’ family. Hence, this study was intended to identify the efficacy of a home based physiotherapy exercise programs versus a combination of physiotherapy with yoga in children with DMD.

Materials and Methods

We adopted a randomized comparative study with a duration of four years. Institution ethics committee approval was obtained for the same. Patients with a confirmed diagnosis of DMD, within the age group of five to ten years were recruited. The patients were included if they could ambulate independently or with minimal assistance. Patients diagnosed with other myopathies, those under regular yoga or physiotherapy treatment, and those under steroids or having cardio-pulmonary issues were excluded. Those who expressed willingness to participate in the study and have provided the consent were randomly divided into two groups using Tippet’s random number table. Patients in group I received two sessions of physiotherapy per day in the morning and in the evening. Those recruited to the second group received single session of yoga and physiotherapy, in the morning and evening respectively. Each session lasted for about 45 minutes. The details of the protocol are provided in Table 1. The patients were taught exercises under supervision for a period of one week. They were then asked to perform the same as home exercise program for a period of one year and to maintain an exercise diary to assess compliance. Regular follow up was done every three months for inspecting compliance and reviewing the exercises.

The demographic details of the patients were recorded on the day of recruitment to the study. QOL was measured using Pediatric quality of life (PedsQLTM) neuromuscular module 3.0 version, which was found to be reliable in DMD.^12,13 It is composed of 25 items comprising three dimensions: my neuromuscular disease, communication, and family resources. Item was scored on a 5 point Likert scale, 0 being ‘it is never a problem’ and 4 being ‘it is almost always a problem.’ The responses were reverse scored and converted into a total score of 100, so that higher scores indicate better QOL.

The PedsQL was assessed during baseline, and at every three months follow up, for a period of one year. Baseline data was analysed using Independent t-test to assess homogeneity. Follow up data was analysed using Repeated measures ANOVA to identify the significant difference within the groups upon each assessment timeframes. Pairwise analysis was performed using Fisher’s Least Significant Difference (LSD) post hoc analysis. 

Results

The study recruited 87 subjects and were randomised into 44 in group I and 43 in group II. Homogeneity was maintained between the groups with respect to the age and duration of the disease. The mean age of subjects in group I was 96.95±16.08 months, whereas in group II the mean age was 99.02±18.41 months (p=0.578). The duration of the disease in the groups were 61.20±16.56 and 65.05±18.64 months respectively (p=0.312). The baseline PedsQL scores demonstrated homogeneity between the groups (Table 2).

Repeated measures ANOVA was performed within each group to identify the variation in outcome measures according to the follow-up assessment. Group I had a significant time effect for ‘My neuromuscular disease’ subscore and the total score, whereas Group II demonstrated significant time effect for ‘My neuromuscular disease’ sub-score alone. Group II showed a reduction in scores after 12 months for communication, family resources, and total score, denoting a negative effect. Pairwise analysis performed using Fisher’s LSD did not show any significant difference between timeframes for communication sub-score in Group II and family resources sub-score in Group I (Table 3). Independent t test analysis performed to identify differences between the groups in each timeframe did not show any significant difference between the groups except for communication sub-score at 6 months follow-up.

Discussion

The ability to perform day-to-day tasks decline progressively in children with DMD, and it is noticed usually at the age of three years. The limitations in the performance of ADL activities are evident with the onset of muscle weakness.¹⁴ The loss of functional independence in-turn affects patient and their family, leading to a reduced QOL. The measure of Quality of life is used in various domains of the healthcare field to identify the effect of a disease, compare the outcomes, and also as part of clinical trials.¹⁵ Fewer studies have reported the effectiveness of therapeutic interventions on the QOL in DMD.¹⁶ In the present study, self-report by the child was not considered, as most of the items in the questionnaire are not age appropriate as per Indian standards. Also some children were school drop outs and their intelligent quotient was low. Hence parents’ proxy reports were considered. No similar studies are available on the effect of physiotherapy and yoga intervention on QOL in DMD for comparison with our findings.

Physiotherapy has been beneficial in various aspects in patients with DMD which include improving muscle power and ambulatory status, maintaining range of movement, preventing contractures and improving subjective well-being of individuals. It maintains the functional status of the individual to a greater extent, thereby prolonging the need of assistance in daily activities. Physiotherapy also provides easiness for those dependent on wheelchairs or assisted ventilation to cope with their situation. There is a significant improvement of QOL with physiotherapy sessions suggesting an improvement in the functioning of patients with DMD and his communication skills. Patient himself is aware of the changes occurring within himself and is able to identify and explain to the therapist what he expects from the treatment sessions. Mild to moderate strengthening exercise programs are found to be beneficial in improving the strength and function in DMD.¹⁷ The studies performed on mouse as well as human models suggest a focus on endurance training in these patient population to elicit therapeutic potential.¹⁸ But the studies have failed to reflect on the benefits pertaining to their quality of life with these interventions.

Significant time effect was observed in the ‘My Neuromuscular Disease’ subgroup of PedsQL in our study groups. Both groups failed to demonstrate time effect in ‘Communication’. It was observed that group I alone demonstrated significant time effect for the total score in PedsQL. Upon analysis, it was worth noting that group I who received two sessions of physiotherapy in a day had demonstrated an increase in quality of life scores (mean difference = 82.39±7.48) when compared to group II who received both yoga and physiotherapy sessions (mean difference = -11.05±50.77) suggesting that physiotherapy intervention is indeed beneficial in improving the QOL in DMD. Group II showed a reduction in scores in Communication, Family Resources, as well for Total scores demonstrating a negative effect with treatment.

Regular practice of yoga has been beneficial in improving the QOL, providing a feeling of self-esteem and promoting positive health.¹⁹ Integration of movements of body segments with the effort of breathing activates the parasympathetic system leading to reduction in heart rate, blood pressure and muscle tone.^20,21 Upon weighing the beneficial effects of yoga, the minimal to no side effects and its cost effectiveness, yoga can be considered as one of the independent treatment strategies in patients with DMD in managing emotional distress and improving QOL through self-regulation of their condition.²² Studies have also identified an add-on effect of yoga with physiotherapy in modulating heart rate variability in patients with DMD.²³ The existing evidence was contradicting to our results as we could not demonstrate a better effect with a combination of yoga and physical therapy in group II. The total scores PedsQL in group I were lower at 12 months, compared to the baseline. But yoga was more acceptable among the patients with DMD than just exercises alone as the family members also took part in sessions along with the patient. Parents also considered it as a recreational moment along with their child.

It has been identified that respiratory functions of DMD patients are poor compared to healthy controls, which was identified through lower values of pulmonary function test.²⁴ This can influence their function leading to poor performance in daily activities and a reduced quality of living. Grootenhuis et al., have shown that DMD influences the QOL in motor, emotional, and social functioning aspects. Ambulant children reported a worse health related QOL for motor functioning. They concluded that a lower QOL does not necessarily relate to a more severe, progressive disease.²⁵ But Baiardini et al., have identified a negative correlation between QOL and wheelchair ambulation and assisted ventilation,²⁶ whereas no association was identified by Kohler et al. ⁵ Parental and patient education status, relationship between family and friends, as well as response shift  (positive feeling about oneself despite facing a chronic illness) can influence the QOL assessment of individuals with DMD.¹⁰

Conclusion

Maintaining a good psychosocial health is imperative for patients with DMD. Younger patients tend to take longer to cope with the disease and adjust emotionally to their condition. This can also influence their peer relationship. Thus, medical professionals must also focus on improving the quality of life of these individuals to maintain their individual function and to tackle the social stigma. We conclude that two physiotherapy sessions in a day are beneficial in improving the quality of life status of this patient population. We also suggest the use of yoga in patients with DMD as a recreational session along with the whole family, which aids in relaxation and building strong social relationships.

Conflict of interests

None

Financial support

Nil