Physical activity and inactivity among different body composition phenotypes in individuals with moderate to very severe chronic obstructive pulmonary disease.

BACKGROUND: The phenotype profiling of individuals with chronic obstructive pulmonary disease (COPD) according to impairments in body composition and level of physical activity in daily life (PADL) needs to be determined. OBJECTIVE: To verify if individuals with COPD classified as physically active/inactive present different characteristics within different body composition phenotypes. METHODS: Individuals with COPD were cross-sectionally stratified into four groups according to fat-free and fat mass indexes: Normal Body Composition (NBC), Obese (Ob), Sarcopenic (Sarc), and Sarcopenic/Obese (Sarc/Ob). Additionally, individuals had their PADL level objectively assessed through activity monitoring during two weekdays for at least 10h/day, and then were classified as physically active (Act) or inactive (Inact) according to international recommendations. Lung function (spirometry), exercise capacity (6-minute walking test [6MWT]) and peripheral muscle strength (1-repetition maximum [1RM]) were also assessed. RESULTS: 176 individuals with COPD (mean±standard deviation age: 67±8 years, body mass index 26±6kg/m2, FEV1 47±16%predicted) were classified as: NBC+Act (17%), NBC+Inact (22%), Ob+Act (6%), Ob+Inact (10%), Sarc+Act (12%), Sarc+Inact (9%), Sarc/Ob+Act (8%) and Sarc/Ob+Inact (16%). The Sarc/Ob+Inact group presented lower 6MWT and 1RM for knee extension compared to NBC+Act, NBC+Inact, and Ob+Act groups (p<0.05). The Sarc/Ob+Inact group also presented lower FEV1% predicted, 1RM for elbow flexion and elbow extension compared to the NBC+Act and NBC+Inact groups and lower 1RM for elbow extension compared to Ob+Inact group (p<0.05). CONCLUSION: The combination of sarcopenia, obesity, and physical inactivity was shown to be detrimental in individuals with COPD. Therefore, this profile is a main therapeutic target for improving PADL level and/or body composition.

Maximum Voluntary Ventilation and Its Relationship With Clinical Outcomes in Subjects With COPD.

BACKGROUND: Previous studies have reported that maximum voluntary ventilation (MVV) may be better associated with commonly used outcomes in COPD than FEV1 and may provide information on respiratory mechanics. In this study, we aimed to investigate the relationship between MVV and clinical outcomes in COPD and to verify whether MVV predicts these outcomes better than FEV1. METHODS: We conducted a cross-sectional study involving individuals with COPD. Lung function was assessed with spirometry; maximum inspiratory and expiratory pressures (PImax and PEmax, respectively) were assessed with manuvacuometry; and functional exercise capacity was assessed with the 6-min-walk test (6MWT). Dyspnea was assessed with the modified Medical Research Council (mMRC) scale; functional status was assessed with the modified Pulmonary Functional Status and Dyspnea Questionnaire (PFSDQ-m); and health status was assessed with the COPD Assessment Test (CAT). Correlations were verified with the Spearman coefficient, and stepwise multiple linear regression models investigated the predictors of clinical outcomes. RESULTS: Our study included 157 subjects: 82 males; median (interquartile range) age 66 (61-73) y; FEV1 46 (33-57) % predicted; 6MWT 86 (76-96) % predicted; PFSDQ-m total score 34 (14-57); and CAT total score 13 (7-19). Moderate correlations were found between MVV and PImax (r = 0.40), 6MWT (r = 0.50), mMRC (r = -0.56), and total scores on the PFSDQ-m (r = -0.40) and the CAT (r = -0.54). In the regression models, MVV was a predictor of almost all clinical outcomes, unlike FEV1. CONCLUSIONS: MVV correlates moderately with clinical outcomes commonly used in the evaluation of individuals with COPD, and MVV is a better predictor of respiratory muscle strength, functional exercise capacity, and patient-reported outcomes than FEV1.

Clinical impact of body composition phenotypes in patients with COPD: a retrospective analysis.

BACKGROUND/OBJECTIVES: Abnormal body composition is an independent determinant of COPD outcomes. To date, it is already known that patient stratification into body composition phenotypes are associated with important outcomes, such as exercise capacity and inflammation, but there are no data comparing physical activity and muscle strength among these phenotypes. Thus, the aim of this study was to compare clinical characteristics and physical function in patients with COPD stratified into body composition phenotypes. SUBJECTS/METHODS: Two-hundred and seventy stable COPD patients were classified according to the 10th and 90th percentiles of sex-age-BMI-specific reference values for fat-free and fat mass indexes into four groups: Normal body composition (NBC), Obese, Sarcopenic, and Sarcopenic-obese (SO). Patients underwent assessment of exercise capacity, peripheral and respiratory muscle strength, physical activity, dyspnea severity, functional status, and symptoms of anxiety and depression. RESULTS: The prevalence of patients classified as NBC, Obese, Sarcopenic, and SO was 39%, 13%, 21%, or 27%, respectively. SO presented lower 6MWT compared with NBC (P < 0.05). Sarcopenic and SO groups presented worse muscle strength compared with NBC (P < 0.05). Sarcopenic group presented more time in moderate-to-vigorous physical activity compared to all other groups (P < 0.05) and less sedentary time when compared with NBC and obese groups (P < 0.05). There were no differences regarding dyspnea severity, functional status, and symptoms of anxiety and depression (P > 0.16). Sarcopenic and SO groups had, respectively, 7.8 [95% CI: 1.6-37.7] and 9.5 [2.2-41.7] times higher odds to have a 6MWT equal or lower to 350 meters. CONCLUSIONS: Body composition phenotypes are associated with physical function in patients with COPD. Sarcopenic-obese patients were the most impaired.

Sedentary Behaviour and Physical Inactivity in Patients with Chronic Obstructive Pulmonary Disease: Two Sides of the Same Coin?

Despite the growing interest in sedentarism, there is no available information on the profile of patients with COPD according to sedentary behaviour (SB) and with a detailed analysis of minute-by-minute bouts. Hence, the aims of this study were to quantify the time spent in SB, light activities and moderate-to-vigorous physical activities (MVPA) and to verify the relationship of MVPA and SB in individuals with COPD, as well as to identify the profile of those physically (in)active and (non)-sedentary. A cross-sectional study in which physical activity in daily life was objectively assessed through the use of SenseWear Pro 2 Armband (BodyMedia) during 2 consecutive weekdays, 12 h/day. Analysis was performed minute-by-minute for each day of each patient. MVPA comprised time spent >3 metabolic equivalents (MET), whereas light activities corresponded to time spent between 1.5 and 3 MET and SB to time spent <1.5 MET. A total of 137 subjects with COPD (66 ± 8years; FEV1 46 [31-57] %pred; BMI 26 [22-30] kg/m2) were analysed. Time spent in MVPA and SB presented strong negative correlation (r = -0.72, P < 0.001). Minute-by-minute analysis showed that patients with COPD spend most of their time in SB. SB accounted for 40% of all bouts >1 minute, whereas only 14% these bouts concern MVPA. Patients combining two positive characteristics (physically active and non-sedentary) have better clinical profile than others. In conclusion, SB is negatively correlated with MVPA in patients with COPD. Furthermore, patients classified as physically active (i.e., those who reach MVPA recommendations) in combination with a non-sedentary lifestyle present markedly better clinical conditions.

Sedentary Behavior Is an Independent Predictor of Mortality in Subjects With COPD.

BACKGROUND: The terms sedentary behavior and physical inactivity have been confusingly mixed. Although the association between physical inactivity and mortality has been shown previously in subjects with COPD, this association had not yet been investigated with regard to sedentarism. The aim of this work was to investigate the impact of sedentary behavior on mortality of subjects with COPD and to propose a cutoff point of sedentarism with prognostic value. METHODS: In this retrospective cohort study, sedentary behavior was assessed with 2 activity monitors (DynaPort and Sensewear armband) in 101 subjects with COPD from 2006 to 2011. Vital status was then ascertained in 2015. The following 6 variables of sedentary behavior were analyzed: average of metabolic equivalent of task (MET)/d (reflecting intensity); time spent/d lying, sitting, and lying + sitting (reflecting duration of sedentary postures); and time spent/d in activities requiring <1.5 MET and <2 MET (reflecting intensity and duration of sedentary time). Cutoff points for sedentarism and their respective prognostic values were investigated for each variable. RESULTS: Forty-one subjects (41%) died over a median (interquartile range) follow-up period of 62 (43-88) months. After adjusting for potential confounders in the Cox regression model, cutoff points from variables that combine duration of sedentary time and intensity <1.5 MET or <2 MET were associated with the increased risk of mortality. The strongest independent cutoff for predicting mortality was ≥8.5 h/d spent in sedentary activities <1.5 MET (area under the curve 0.76; hazard ratio 4.09, 95% CI 1.90-8.78; P < .001). CONCLUSIONS: Sedentary behavior was an independent predictor of mortality in subjects with COPD, even adjusting for moderate-to-vigorous physical activity and a number of other variables. Mortality was higher in subjects with COPD who spend ≥8.5 h/d in activities requiring <1.5 MET. These findings may open room for future studies aiming at decreasing sedentary time as a promising strategy to reduce mortality risk in subjects with COPD.