@article {1675186,
	title = {Associations Between Muscle Weakness and Clinical Outcomes in Current and Former Smokers},
	journal = {Chronic Obstr Pulm Dis},
	volume = {10},
	number = {1},
	year = {2023},
	month = {2023 Jan 25},
	pages = {112-121},
	abstract = {INTRODUCTION: Smokers with chronic obstructive pulmonary disease (COPD) are at increased risk of muscle weakness. There are limited data describing weakness in smokers with normal spirometry and preserved ratio-impaired spirometry (PRISm), 2 subgroups at risk of respiratory symptom burden and activity limitations. In this study, we evaluated the associations of 2 weakness measures, sit-to-stand (STS) and handgrip strength (HGS), with clinical outcomes in smokers with COPD, normal spirometry, and PRISm.

METHODS: We evaluated 1972 current and former smokers from the COPD Genetic Epidemiology (COPDGene{\textregistered}) cohort with STS and HGS measurements at their 10-year study visit. Multivariable regression modeling was used to assess associations between weakness measures and the 6-minute walk distance (6MWD) test, the St George{\textquoteright}s Respiratory Questionnaire (SGRQ), the Short-Form-36 (SF-36), severe exacerbations, and prospective mortality, reported as standardized coefficients (β), odds ratios (ORs), or hazard ratios (HRs).

RESULTS: Compared with HGS, STS was more strongly associated with the 6MWD (β=0.45, p\<0.001 versus. β=0.25, p\<0.001), SGRQ (β=-0.24, p\<0.001 versus β=-0.18, p\<0.001), SF-36 Physical Functioning (β=0.36, p\<0.001 versus β=0.25, p\<0.001), severe exacerbations (OR 0.95, p=0.04 versus OR 0.97, p=0.01), and prospective mortality (HR 0.83, p=0.001 versus HR 0.94, p=0.03). Correlations remained after stratification by spirometric subgroups. Compared with males, females had larger magnitude effect sizes between STS and clinical outcomes.

CONCLUSIONS: STS and HGS are easy to perform weakness measures that provide important information about functional performance, health-related quality of life, severe exacerbations, and survival in smokers, regardless of spirometric subgroup. This iterates the importance of screening current and former smokers for weakness in the outpatient setting.},
	issn = {2372-952X},
	doi = {10.15326/jcopdf.2022.0365},
	author = {Zou, Richard H and Nouraie, S Mehdi and Rossiter, Harry B and McDonald, Merry-Lynn and DeMeo, Dawn L and Mason, Stefanie and Washko, George R and Saha, Punam K and Make, Barry J and Casaburi, Richard and Regan, Elizabeth A and Bon, Jessica}
}