Table 1. Summary of studies investigating the effects of pulmonary rehabilitation on components of the frailty phenotype.
| First author, year (reference) | Study design | n | Pulmonary rehabilitation | Observation | Main result | |
|---|---|---|---|---|---|---|
| Frequency | Duration | |||||
| Weight loss | ||||||
| van de Bool, 2017 (28) | RCT, double-blind | 81 | 2-3/week | 4 months | Total body mass, BMI, FM, SMM | After PR, body composition results demonstrated significantly increased body mass, skeletal muscle mass, and fat mass in the control group |
| Gurgun, 2013 (72) | RCT, prospective | 46 | 2/week | 8 weeks | Weight, BMI, FFMI | Combining oral NS with PR in depleted COPD patients improved body composition |
| Exhaustion | ||||||
| Van Herck, 2019 (33) | Responder analyses | 446 | 5 days/week | 12 weeks | CIS subjective fatigue | After PR, the mean CIS-Fatigue score improved significantly and was clinically relevant |
| Gordon, 2019 (36) | Meta-analysis | 734 | 2-5/week | 4-16 weeks | HADS-A, HADS-D | PR conferred significant, clinically relevant benefits on anxiety and depression symptoms |
| Peters, 2017 (37) | Cluster analysis | 160 | 5 days/week | 12 weeks | CIS subjective fatigue | After PR, the mean CIS-Fatigue score significantly improved, and the improvement persisted one year later |
| Weakness | ||||||
| Iepsen, 2015 (49) | Meta-analysis | 331 | 2-3/week | 3-12 weeks | Muscle strength | A combination of resistance and endurance training increased leg muscle strength in COPD |
| Vonbank, 2012 (73) | RCT | 36 | 2/week | 12 weeks | Muscle strength | Muscle strength improved in all groups |
| Chen, 2016 (50) | Meta-analysis | 276 | 2-7/week | 4-10 weeks | Quadriceps strength | NMES appeared to be effective in enhancing quadricep strength in patients with moderate-to-severe COPD |
| Slowness | ||||||
| Li, 2019 (54) | Meta-analysis | 414 | 2-7/week | 2-12 months | 6WMT | PR programs had beneficial influence in exercise function in elderly COPD patients |
| Kon, 2014 (56) | Longitudinal | 301 | 2/week | 8 weeks | 4MGS | The 4MGS improved with PR |
| Low physical activity | ||||||
| Probst, 2006 (63) | RCT | 11 | 3/week | 12 weeks | 6WMT, Wmax | As expected, training Wmax increased significantly after 12 weeks of exercise |
| Vogiatzis, 2002 (62) | RCT | 36 | 40 min/day & 2 days/week | 12 weeks | PWR, CRDQ | Interval training elicited substantial training effects. |
| Nagai, 2018 (67) | Cross-sectional | 886 | - | - | SB, LPA, MVPA, FP | Replacing 30 min of SB with an equivalent amount of LPA decreases the risk for frailty in older adults. Moreover, increasing LPA appeared more feasible than increasing MVPA in older adults, with substantial benefit |
Abbreviations: BMI, body mass index; CIS, Checklist Individual Strength; COPD, chronic obstructive pulmonary disease; CRDQ: Chronic Respiratory Disease Questionnaire; FM, fat mass; FP, frailty phenotype; HADS-A, Hospital Anxiety and Depression Scale-Anxiety; HADS-D, Hospital Anxiety and Depression Scale-Depression; LPA, light-intensity physical activity; MVPA, moderate-to-vigorous intensity physical activity; NMES, neuromuscular electrical stimulation; NS, nutritional supplementation; PR, pulmonary rehabilitation; RCT, randomized clinical trial; SB: sedentary behavior; SMM, skeletal muscle mass; Wmax: baseline maximal workload; WR: peak work-rate; 4MGS, 4-meter gait speed; 6MWT, 6-min walk test.