Smoking and COPD Independently & Synergistically Drive BMI Decline, New Research Shows
LONDON - Individuals with chronic obstructive pulmonary disease (COPD), particularly those with a history of smoking, experience distinct and often accelerated declines in body mass index (BMI) over time, according to a new analysis of longitudinal data. The study underscores that both smoking and COPD independently contribute to this decline, with a particularly concerning synergistic effect when both conditions coexist. These findings, published in Thorax, have significant implications for nutritional support and early intervention strategies aimed at mitigating cachexia – the wasting syndrome - and improving outcomes for millions affected by respiratory illness.
The progressive loss of weight and muscle mass associated with COPD is a major predictor of morbidity and mortality, independent of disease severity. While low BMI is a known risk factor, this research highlights the dynamic nature of BMI trajectories and the critical roles of smoking history and COPD diagnosis. Understanding these independent and combined effects is crucial for identifying at-risk individuals and tailoring interventions to prevent or slow down the development of cachexia, ultimately improving quality of life and extending survival.
Researchers analyzed data from the ECLIPSE cohort, a large, multi-center study following over 2,000 individuals with and without COPD, over a period of five years.They identified three distinct BMI trajectories: a stable trajectory, a gradual decline, and a rapid decline. Individuals with COPD were significantly more likely to be in the rapid decline trajectory compared to those without the disease.
Importantly, the study revealed that current and former smokers exhibited lower baseline BMIs and were more prone to rapid BMI decline, even after accounting for COPD status. The most pronounced declines were observed in individuals with COPD and a history of smoking, suggesting a synergistic interaction between these two factors. Specifically, smokers with COPD experienced a significantly faster rate of BMI loss compared to non-smokers with COPD or smokers without COPD.
Further analysis indicated that factors such as age, gender, and disease severity also influenced BMI trajectories, but smoking and COPD remained significant independent predictors of decline. The findings reinforce the importance of smoking cessation as a key component of COPD management and highlight the need for proactive nutritional assessments and interventions in individuals with both conditions.
A 2016 study by Sanders et al. in J. Cachexia Sarcopenia Muscle provided new insights into cachexia in COPD and therapeutic perspectives, while McDonald et al. (2019) in Respir Res. emphasized that cachexia prevalence in COPD extends beyond simply low BMI, linking it to increased mortality. These studies,alongside the current research,collectively underscore the urgency of addressing weight loss and muscle wasting in COPD patients to improve clinical outcomes.