Clinical outcome and cost-effectiveness of a 1-year nutritional intervention programme in COPD patients with low muscle mass: The randomized controlled NUTRAIN trial.

BACKGROUND AND AIMS: The efficacy of nutritional intervention to enhance short- and long-term outcomes of pulmonary rehabilitation in COPD is still unclear, hence this paper aims to investigate the clinical outcome and cost-effectiveness of a 12-month nutritional intervention strategy in muscle-wasted COPD patients. METHODS: Prior to a 4-month pulmonary rehabilitation programme, 81 muscle-wasted COPD patients (51% males, aged 62.5 ± 0.9 years) with moderate airflow obstruction (FEV1 55.1 ± 2.2% predicted) and impaired exercise capacity (Wmax 63.5 ± 2.4% predicted) were randomized to 3 portions of nutritional supplementation per day (enriched with leucine, vitamin D and polyunsaturated fatty acids) [NUTRITION] or PLACEBO (phase 1). In the unblinded 8-month maintenance phase (phase 2), both groups received structured feedback on their physical activity level assessed by accelerometry. NUTRITION additionally received 1 portion of supplemental nutrition per day and motivational interviewing-based nutritional counselling. A 3-month follow-up (phase 3) was included. RESULTS: After 12 months, physical capacity measured by quadriceps muscle strength and cycle endurance time were not different, but physical activity was higher in NUTRITION than in PLACEBO (Δ1030 steps/day, p = 0.025). Plasma levels of the enriched nutrients (p < 0.001) were higher in NUTRITION than PLACEBO. Trends towards weight gain in NUTRITION and weight loss in PLACEBO led to a significant between-group difference after 12 months (Δ1.54 kg, p = 0.041). The HADS anxiety and depression scores improved in NUTRITION only (Δ-1.92 points, p = 0.037). Generic quality of life (EQ-5D) was decreased in PLACEBO but not in NUTRITION (between-group difference after 15 months 0.072 points, p = 0.009). Overall motivation towards exercising and healthy eating was high and did not change significantly after 12 months; only amotivation towards healthy eating yielded a significant between-group difference (Δ1.022 points, p = 0.015). The cost per quality-adjusted life-year after 15 months was EUR 16,750. CONCLUSIONS: Nutritional intervention in muscle-wasted patients with moderate COPD does not enhance long-term outcome of exercise training on physical capacity but ameliorates plasma levels of the supplemented nutrients, total body weight, physical activity and generic health status, at an acceptable increase of costs for patients with high disease burden.

A randomized clinical trial investigating the efficacy of targeted nutrition as adjunct to exercise training in COPD.

BACKGROUND: Evidence regarding the efficacy of nutritional supplementation to enhance exercise training responses in COPD patients with low muscle mass is limited. The objective was to study if nutritional supplementation targeting muscle derangements enhances outcome of exercise training in COPD patients with low muscle mass. METHODS: Eighty-one COPD patients with low muscle mass, admitted to out-patient pulmonary rehabilitation, randomly received oral nutritional supplementation, enriched with leucine, vitamin D, and omega-3 fatty acids (NUTRITION) or PLACEBO as adjunct to 4 months supervised high intensity exercise training. RESULTS: The study population (51% males, aged 43-80) showed moderate airflow limitation, low diffusion capacity, normal protein intake, low plasma vitamin D, and docosahexaenoic acid. Intention-to-treat analysis revealed significant differences after 4 months favouring NUTRITION for body mass (mean difference ± SEM) (+1.5 ± 0.6 kg, P = 0.01), plasma vitamin D (+24%, P = 0.004), eicosapentaenoic acid (+91%,P < 0.001), docosahexaenoic acid (+31%, P < 0.001), and steps/day (+24%, P = 0.048). After 4 months, both groups improved skeletal muscle mass (+0.4 ± 0.1 kg, P < 0.001), quadriceps muscle strength (+12.3 ± 2.3 Nm,P < 0.001), and cycle endurance time (+191.4 ± 34.3 s, P < 0.001). Inspiratory muscle strength only improved in NUTRITION (+0.5 ± 0.1 kPa, P = 0.001) and steps/day declined in PLACEBO (-18%,P = 0.005). CONCLUSIONS: High intensity exercise training is effective in improving lower limb muscle strength and exercise performance in COPD patients with low muscle mass and moderate airflow obstruction. Specific nutritional supplementation had additional effects on nutritional status, inspiratory muscle strength, and physical activity compared with placebo.

Nutritional targets to enhance exercise performance in chronic obstructive pulmonary disease.

PURPOSE OF REVIEW: This review presents current knowledge regarding the rationale and efficacy of nutrition as an ergogenic aid to enhance the effects of exercise and training in chronic obstructive pulmonary disease (COPD). RECENT FINDINGS: Altered body composition and skeletal muscle dysfunction in COPD suggest that exercise capacity can be targeted via several metabolic routes. Muscle metabolic alterations in COPD include a reduced oxidative metabolism and enhanced susceptibility for oxidative stress. Muscle wasting may be associated with deficiencies of vitamin D and low branched-chain amino acid levels. Exercise training is of established benefit in COPD but clear-cut clinical trial evidence to support the performance enhancing effect of nutritional intervention is lacking. One randomized controlled trial suggested that augmentation of training with polyunsaturated fatty acids may improve exercise capacity. Conflicting results are reported on dietary creatine supplementation in patients with COPD receiving pulmonary rehabilitation and results from acute intervention studies do not directly imply long-term effects of glutamate or glutamine supplementation as an ergogenic aid in COPD. Recent data indicate that not only muscle but also visceral fat may be an important additional target for combined nutrition and exercise intervention in COPD to improve physical performance and decrease cardiometabolic risk. SUMMARY: There is a clear need for adequately powered and controlled intervention and maintenance trials to establish the role of nutritional supplementation in the enhancement of exercise performance and training and the wider management of the systemic features of the disease.