James R. Walsh

Balance is impaired in people with chronic obstructive pulmonary disease

BACKGROUND It has recently been suggested that people with chronic obstructive pulmonary disease have an increased risk of falls. Although falls risk is multifactorial, impaired balance may contribute. The primary aim of this study was to compare balance between people with and without chronic obstructive pulmonary disease and the secondary aim was to determine if balance deteriorates when respiratory demand is increased by upper limb exercise. METHODS Twelve people with chronic obstructive pulmonary disease and 12 healthy control subjects participated in this study. Participants stood on a force plate to record centre of pressure displacement during a range of conditions that challenge balance. Lumbar spine and hip motion were measured with inclinometers. Balance trials were performed before and after participation in upper limb exercise that increased respiratory demand in those with chronic obstructive pulmonary disease. FINDINGS People with chronic obstructive pulmonary disease had increased mediolateral centre of pressure displacement and increased angular motion of the hip compared to healthy controls. Mediolateral centre of pressure displacement was further increased in people with chronic obstructive pulmonary disease following exercise, but unchanged in controls. Anteroposterior centre of pressure displacement did not differ between groups. INTERPRETATION People with chronic obstructive pulmonary disease have reduced control of balance in the mediolateral direction. This may contribute to an increased risk of falls in this population.

Anxiety and depression—Important psychological comorbidities of COPD

Anxiety and depression are common and important comorbidities in patients with chronic obstructive pulmonary disease (COPD). The pathophysiology of these psychological comorbidities in COPD is complex and possibly explained by common risk factors, response to symptomatology and biochemical alterations. The presence of anxiety and/or depression in COPD patients is associated with increased mortality, exacerbation rates, length of hospital stay, and decreased quality of life and functional status. There is currently no consensus on the most appropriate approach to screening for anxiety and depression in COPD. Treatment options include psychological [relaxation, cognitive behavioural therapy (CBT), self-management] and pharmacological interventions. Although there is some evidence to support these treatments in COPD, the data are limited and mainly comprised by small studies. Pulmonary rehabilitation improves anxiety and depression, and conversely these conditions impact rehabilitation completion rates. Additional high quality studies are urgently required to optimise screening and effective treatment of anxiety and depression in patients with COPD, to enhance complex chronic disease management for these patients.

Predictive Utility of the 6-Minute Walk Distance on Survival in Patients Awaiting Lung Transplantation

BACKGROUND The 6-minute walk distance (6MWD) is a widely used clinical indicator of exercise capacity. Although used as part of the assessment process in determining a candidates suitability for lung transplantation (LT), the literature describing the impact of the 6MWD in predicting survival on LT waiting lists is limited. This study aimed to determine the hazard function associated with the 6MWD, and its utility relative to other prognostic variables. METHODS A retrospective chart review was conducted on 163 patients who were listed for single or double LT, and either survived to transplant or died while on the waiting list. A Cox regression for survival analysis, stratified by diagnostic group, was conducted utilizing the 6MWD, demographic variables and measures of cardiopulmonary function. RESULTS The 6MWD proved to be the only significant covariate in the Cox regression for survival analysis (p < 0.001), with all other variables eliminated as non-significant. Furthermore, there was a protective effect for each unit increase in the 6MWD [Exp (B) = 0.994, 95% confidence interval 0.990 to 0.997]. CONCLUSIONS This research demonstrates that the 6MWD is useful for stratifying patients on the LT waiting list by identifying those patients with a significantly higher risk of mortality.

Static balance is affected following an exercise task in chronic obstructive pulmonary disease.

PURPOSE To investigate balance following a submaximal exercise task (6-minute walk test [6MWT]) in patients with chronic obstructive pulmonary disease (COPD). METHODS A consecutive sample of 19 patients with COPD from an institutional pulmonary rehabilitation program served as participants. The following measures were recorded before and following a 6MWT: (1) timed-up and go (TUG) test, (2) step-up test, and (3) quiet standing for 30 seconds with eyes open and closed in a narrow and semi-tandem stance. Displacement of the body at the level of the waist was recorded using a swaymeter. Data were analyzed using a linear mixed model. RESULTS In the semi-tandem stance with eyes closed post-6MWT, increases in total sway (165.9 mm vs 240.0 mm, P = .043) and mediolateral sway (45.8 mm vs 66.6 mm, P = .011) were found in comparison with pre-6MWT measures. The exercise task did not affect the TUG test performance (8.3 seconds vs 9.0 seconds, P = .213), number of steps completed during the step-up test (10 vs 10, P = .233), or sway during the semi-tandem stance with eyes open; narrow base, eyes open or closed (P > .05). Conclusions A submaximal exercise task in patients with COPD affects balance during static standing tasks in the absence of visual input. This may have implications for functional performance following exercise in patients with chronic respiratory disease.

Impaired exercise capacity after lung transplantation is related to delayed recovery of muscle strength.

Lung transplant recipients report reduced exercise capacity despite satisfactory graft function. We analysed changes in lung function, six‐min walk distance (6MWD), and quadriceps strength in the first 26‐wk post‐transplant and examined what factors predict 6MWD recovery. All lung transplant recipients at a single institution between June 2007 and January 2011 were considered for inclusion. Lung function, 6MWD, and quadriceps strength corrected for body weight (QS%) were recorded pre‐ and two‐, six‐, 13‐, and 26‐wk post‐transplant. Fifty recipients, of mean (±SD) age 42 (±13) yr, were studied. Mean FEV1% and 6MWD improved from 26.4% to 88.9% and from 397 to 549 m at 26 wk, respectively (both p < 0.001). QS% declined in the first two wk but had improved to above pre‐transplant levels by 26 wk (p = 0.027). On multivariate analysis (n = 35), lower pre‐transplant exercise capacity and greater recovery in muscle strength explained most of the improvement in exercise capacity. Delayed recovery of exercise capacity after lung transplantation is unrelated to delay in improvement in graft function, but occurs secondary to the slow recovery of muscle strength. Our findings show that additional controlled trials are needed to better understand the influence of exercise rehabilitation on improvement in exercise capacity post‐transplantation.

Metabolic disease and participant age are independent predictors of response to pulmonary rehabilitation.

PURPOSE: The study aims were (1) to determine whether baseline measures—including the Body Mass Index, Airflow Obstruction, Dyspnea, and Exercise Capacity (BODE) index; Age, Dyspnea, and Airflow Obstruction (ADO) index; physical activity; comorbidities (cardiac, metabolic, or musculoskeletal disease); and the number of hospitalizations over the previous 12 months—can predict responders in 6-minute walk distance (6MWD) following pulmonary rehabilitation (PR) and (2) to determine whether different methods in defining improvement in 6MWD affected identifying responders to PR. METHODS: All participants with chronic obstructive pulmonary disease who attended PR at our institution between 2004 and 2009 were evaluated. A participant was classified as a responder with improvement in 6MWD (≥25 m or ≥2 SD of this dataset coefficient of repeatability). RESULTS: A total of 203 participants (mean age, 68.2 ± 8.7 years; mean predicted forced expiratory volume in 1 second, 52.5 ± 22.4%) were analyzed. One hundred twenty participants (59.1%) had a comorbidity categorized as cardiac, metabolic, or musculoskeletal disease. The binary logistic regression models showed that younger participants (P ⩽ .015) and, when using the coefficient of repeatability method (≥60.9 m), participants with metabolic disease (P = .040) were the only independent predictors of response. No other measure, including participant BODE or ADO index scores, contributed to either model. CONCLUSION: Identifying responders in exercise capacity following PR remains difficult, with only age and participants with metabolic disease identified as independent predictors.

A Simple Clinical Measure of Quadriceps Muscle Strength Identifies Responders to Pulmonary Rehabilitation

The aim was to determine if baseline measures can predict response to pulmonary rehabilitation in terms of six-minute walk distance (6MWD) or quality of life. Participants with COPD who attended pulmonary rehabilitation between 2010 and 2012 were recruited. Baseline measures evaluated included physical activity, quadriceps strength, comorbidities, inflammatory markers, and self-efficacy. Participants were classified as a responder with improvement in 6MWD (criteria of ≥25 m or ≥2SD) and Chronic Respiratory Questionnaire (CRQ; ≥0.5 points/question). Eighty-five participants with a mean (SD) age of 67(9) years and a mean forced expiratory volume in one second of 55(22)% were studied. Forty-nine and 19 participants were responders when using the 6MWD criteria of ≥25 m and ≥61.9 m, respectively, with forty-four participants improving in CRQ. In a regression model, responders in 6MWD (≥25 m criteria) had lower baseline quadriceps strength (P = 0.028) and higher baseline self-efficacy scores (P = 0.045). Independent predictors of 6MWD response (≥61.9 m criteria) were participants with metabolic disease (P = 0.007) and lower baseline quadriceps strength (P = 0.016). Lower baseline CRQ was the only independent predictor of CRQ response. A participant with relatively lower baseline quadriceps strength was the strongest independent predictor of 6MWD response. Metabolic disease may predict 6MWD response, but predictors of CRQ response remain unclear.

Quadriceps muscle weakness identifies responders to pulmonary rehabilitation

Abstract S-227 for Poster Session: Reproductive Immunology (Saturday, 3/24/2012, 9:00 AM - 11:00 AM)

Seasonal variation and living alone are related to non-completion in a pulmonary rehabilitation program

Despite the prevalence of acute cough in children (<2 weeks duration), the burden to parents and families is largely unknown. The objectives of this study were to determine the parental burden of children’s acute cough, and to evaluate psychological and other infl uences on the reported burden of acute cough in children. Methods Parents of children with a current acute cough (<2 weeks) at enrolment completed 4 questionnaires (state trait anxiety inventory (STAI); short form health survey (SF-8); depression, anxiety and stress 21-item scale (DASS21); and our preliminary 48-item parent acute cough specifi c quality of life (PAC-QOL48) questionnaire). In PAC-QOL48, lower scores refl ect worse QOL. Results Median age of the 104 children enrolled was 2.63 (IQR 1.42, 4.79) years, 54 were boys. Median length of cough at enrolment was 3 (IQR 2, 5) days. Median total PAC-QOL48 score of parents enrolled at presentation to the emergency department (n = 70) was signifi cantly worse than of parents enrolled through the community (n = 24) (p < 0.01). More than half (n = 55) had sought medical assistance more than once for the current acute coughing illness. PAC-QOL48 score was signifi cantly negatively correlated to verbal category descriptive and visual analogue scale cough scores (Spearman r = −0.26, p = 0.05 and r = −0.46, p = 0.01 respectively) and DASS21 total score (r = −0.36, p = 0.01), but not to child’s age. Conclusions Consistent with data on chronic cough, stress was the predominant factor of parental burden. This study highlights the ongoing need for clinicians to be cognizant of parental worries and concerns when their children are coughing, and for further research into safe and effective therapies for acute cough in children.