Exercise Plus High-Protein Diet May Benefit LOPD Patients on Lumizyme
Combining exercise training with a high-protein diet improves exercise tolerance, pulmonary function, and quality of life among late-onset Pompe disease (LOPD) patients taking Lumizyme (alglucosidase alfa) for years, a small study found.
The study, “Exercise training alone or in combination with high-protein diet in patients with late onset Pompe disease: results of a cross over study,” was published in the Orphanet Journal of Rare Diseases.
LOPD progressively affects exercise tolerance — the ability to produce and maintain adequate strength to accomplish a task — motor and respiratory functions, and quality of life.
Following the introduction of enzyme replacement therapy (ERT) with Sanofi Genzyme‘s Lumizyme as a regular treatment for Pompe patients, lifestyle interventions such as a high-protein diet and exercise training fell out of regular practice. Recent studies, however, show aerobic exercise benefits LOPD patients treated with ERT, but none are known to have looked at exercise plus a high-protein diet in this population.
While exercise can counteract general loss of muscle tone and the chronic inflammation that accompanies inactivity, a high-protein, low-carbohydrate diet can reduce glycogen accumulation in muscles, helping to ease damage.
Researchers in Italy hypothesized that the two interventions would be more beneficial than either alone. As such, their primary goal was to assess the effects of an individualized exercise training program, alone or given with a high-protein diet, on exercise tolerance, muscle and pulmonary health, and quality of life in people with LOPD treated with Lumizyme.
Their crossover study enrolled 13 patients with a median age of 49, taking Lumizyme for a median of six years. None were exercising regularly, and eight people were using non-invasive nighttime ventilation.
Each was assigned first to a control period of neither exercise nor diet restrictions, followed by assignment to one of two treatment types in a random order. Here, the treatments consisted of an exercise only period, and an exercise and controlled diet period. Each period lasted 26 weeks, separated by “washout” periods of 13 weeks for people crossing between exercise only and exercise plus diet.
Exercise sessions included warm-up exercises, stretching and balance exercises, moderate strength training, and moderate-intensity aerobic exercise on a cycle ergometer, a type of stationary exercise bicycle. The high-protein diet consisted of 25–30% protein, 30–35% carbohydrate, and 35–40% fat.
Two participants dropped out for personal reasons, and one completed only two of the three treatment periods.
Patients’ average body mass index decreased after the exercise with diet period, from a median value of 21.7 to 21.3 (18.5–24.9 is considered a normal weight range). No differences were observed in body composition.
Maximal aerobic power — as measured by oxygen intake with Quark b2 (from Cosmed) — dropped after the control period, then increased after exercise alone and, even more significantly, after exercise with diet. Peak work rate and time to exhaustion showed similar patterns, although a statistically significant difference was not always reached.
Blood levels of creatine kinase (a marker of muscle damage) and lactate dehydrogenase, an indicator of tissue damage, were significantly reduced following the exercise-plus-diet treatment when compared with exercise alone.
Likewise, results of pulmonary function tests did not change between the control and exercise only periods. In contrast, forced expiratory volume significantly improved after exercise and diet.
Patients’ quality of life was measured using the SF-36 questionnaire, a 36-item survey that scores various measures of physical, emotional, social, and mental well-being. Participants demonstrated a trend toward improvements in the mental component scale following the exercise period, and in the mental health and mental component scale after the exercise-plus-diet period.
The differences reached statistical significance in the areas of general health and vitality.
“Since LOPD in advanced stages causes significant disability and ERT efficacy seems to decrease during long-term treatment, moderate-intensity aerobic exercise training in association with a high-protein diet might be promoted as part of the standard care of these patients, in order to reduce their demand for assistance and improve their quality of life,” the investigators wrote.