Weight loss intervention may improve COPD symptoms

In addition to cardiometabolic benefits, a lifestyle intervention aimed at weight loss in patients with chronic obstructive pulmonary disease (COPD) who are overweight or obese may reduce COPD symptoms, according to results of the INSIGHT COPD trial presented at ATS 2022.

The INSIGHT COPD trial was a 12-month, multicentre trial involving 684 individuals (mean age 67 years, 41.2 percent female) with COPD (generally moderate severity with FEV₁ 58.1 percent) from 38 clinics in the US. Inclusion criteria were BMI 25.0–44.9 kg/m² (mean BMI 33 kg/m²) and a modified Medical Research Council (mMRC) dyspnoea score of ≥1. They were randomized to a self-directed low-intensity lifestyle intervention for 12 months or a control group (n=340 in each group).

At 12 months, there was a significant improvement in the six-minute walk test (6MWT) among patients in the intervention vs control group (adjusted difference, 42.29 feet, 95 percent confidence interval [CI], 7.93–76.65; p=0.02). [ATS 2022, session B14]

Dyspnoea at the end of the 6MWT was also significantly reduced among patients in the intervention vs control arm (adjusted difference, -0.36, 95 percent CI, -0.63 to -0.09; p=0.008), while weight loss was greater in the intervention arm (adjusted difference, -1.34 kg, 95 percent CI, -2.33 to -0.34; p=0.008).

Framingham Risk Score was also significantly improved among patients in the intervention vs control arm (adjusted difference, -0.41, 95 percent CI, -0.71 to -0.10; p=0.009), as was BMI (adjusted difference, -0.51, 95 percent CI, -0.85 to -0.17; p=0.004), health-related quality of life (QoL) as per Short-Form 12 Physical Component Summary (PCS) score (adjusted difference, 1.48, 95 percent CI, 0.35–2.60; p=0.01), and COPD symptom-related QoL as per St George’s Respiratory Questionnaire for COPD total score (adjusted difference, -2.42, 95 percent CI, -4.55 to -0.28; p=0.03).

Overweight and obesity are common comorbidities in COPD, with about 70 percent of patients with COPD being overweight or obese, said the authors. “In addition to the deleterious cardiometabolic effects, excess weight also increases the work of breathing,” they continued.

Guidelines on management of COPD symptoms focus on inhaled medications, and there is a missed opportunity to identify whether lifestyle interventions for weight loss could improve COPD symptoms, they said.

“[Results from the INSIGHT COPD trial showed that] among participants with COPD who were overweight or obese, a self-guided video-based lifestyle [intervention] led to modest improvements in exercise capacity, dyspnoea, and weight loss,” the authors said.

“The intervention also led to improvements in cardiovascular risk and modest improvements in QoL,” they added, suggesting that the beneficial outcomes may have been driven by the prevention of decline. “[Furthermore,] the impact on cardiovascular disease risk measures was not seen in pulmonary rehabilitation,” they said.