Performance of bioelectrical impedance analysis compared to dual X-ray absorptiometry (DXA) in Veterans with COPD

We examined the performance of a commercially-available handheld bioimpedance (BIA) device relative to dual X-ray absorptiometry (DXA) to assess body composition differences among Veterans with chronic obstructive pulmonary disease (COPD). Body composition was measured using DXA and BIA (Omron HBF-306C) at a single time point. Correlations between BIA- and DXA-assessed percent fat, fat mass, and fat-free mass were analyzed using Spearman (ρ) and Lin Concordance Correlation Coefficients (ρ_c). Mean differences in fat mass were visualized using Bland–Altman plots. Subgroup analyses by obesity status (BMI < 30 versus ≥ 30) were performed. Among 50 participants (96% male; mean age: 69.5 ± 6.0 years), BIA-assessed fat mass was strongly correlated (ρ = 0.94) and demonstrate excellent concordance (ρ_c = 0.95, [95%CI: 0.93–0.98]) with DXA, with a mean difference of 2.7 ± 3.2 kg between BIA and DXA. Although Spearman correlations between BIA- and DXA-assessed percent fat and fat-free mass were strong (ρ = 0.8 and 0.91, respectively), concordance values were only moderate (ρ_c = 0.67 and 0.74, respectively). Significantly stronger correlations were observed for obese relative to non-obese subjects for total percent fat (ρ_obese = 0.85 versus ρ_non-obese = 0.5) and fat mass (ρ_obese = 0.96 versus ρ_non-obese = 0.84). A handheld BIA device demonstrated high concordance with DXA for fat mass and moderate concordance for total percent fat and fat-free mass.

ClinicalTrials.gov: NCT02099799.

The Effect of a web-based physical activity intervention on COPD knowledge: A secondary cohort study

BACKGROUND

Novel strategies to complement current methods of education delivery by healthcare providers in clinic encounters or in pulmonary rehabilitation are needed to promote COPD self-management.

METHODS

We developed a COPD web-based platform that delivers education as part of a physical activity intervention. We examined COPD knowledge in persons with COPD who used a web-mediated, pedometer-based physical activity intervention. Knowledge was assessed with the Bristol COPD Knowledge Questionnaire (BCKQ) at baseline, 3, 6, 9, and 12 months. Scores range from 0 to 100, with higher scores indicating greater knowledge. Repeated measures ANOVA (PROC MIXED, SAS 9.4) examined trends across the 12 months and identified changes from baseline at 3, 6, 9, and 12 months.

RESULTS

We enrolled 72 participants with COPD, 93% males with mean ± sd age of 69 ± 7 years and FEV1% predicted of 60 ± 23%. There was a significant increase from baseline to 9 months (p = 0.012), although this increase did not persist at 12 months. Among the 13 topics, participants scored the highest at baseline on smoking knowledge (65.3 ± 17.4) and the lowest on inhaled steroids (9.7 ± 15.4). Across the 12 months, there were significant increases in knowledge about inhaled bronchodilators (p = 0.011) and inhaled steroids (p = 0.035). At 12 months, there were significant improvements in knowledge about exercise (p = 0.004), vaccination (p = 0.027), inhaled bronchodilators (p = 0.002), and inhaled steroids (p = 0.002).

CONCLUSION

An internet-mediated intervention may provide another option for COPD education delivery and support for disease self-management.

A randomised trial of a web-based physical activity self-management intervention in COPD

Improving exercise capacity is a primary objective in COPD. Declines in exercise capacity result in reduced physical activity and health-related quality of life (HRQoL). Self-management interventions can teach patients skills and behaviours to manage their disease. Technology-mediated interventions have the potential to provide easily accessible support for disease self-management. We evaluated the effectiveness of a web-based self-management intervention, focused on physical activity promotion, on exercise capacity in COPD. This 6-month randomised controlled trial (NCT02099799) enrolled 153 persons with COPD at two US sites (VABoston, n=108; VABirmingham, n=45). Participants were allocated (1:1) to the web-based self-management intervention (physical activity promotion through personalised, progressive step-count goals, feedback, online COPD-related education and social support via an online community) or usual care. The primary outcome was exercise capacity (6-min walk distance (6 MWD)). Secondary outcomes included physical activity (daily steps per day), HRQoL (St. George's Respiratory Questionnaire Total Score), dyspnoea, COPD-related knowledge and social support. Change in step-count goals reflected intervention engagement. Participants' mean age was 69 (sd=7), and mean forced expiratory volume in 1 s % predicted was 61% (sd=21%). Change in 6MWD did not differ between groups. Intervention participants improved their mean daily step counts by 1312 more than those in the usual care group (p<0.001). Groups did not differ on other secondary outcomes. VABirmingham participants were significantly more engaged with the intervention, although site did not modify the effect of the intervention on 6MWD or secondary outcomes. The intervention did not improve exercise capacity but improved physical activity at 6 months. Additional intervention modifications are needed to optimise its COPD self-management capabilities.

A web-based self-management intervention improved physical activity but not exercise capacity. There is a need to develop and study accessible self-management interventions for COPD.https://bit.ly/3iT1yvU

Co-occurrence of pain and dyspnea in Veterans with COPD: Relationship to functional status and a pilot study of neural correlates using structural and functional magnetic resonance imaging

Persons with COPD experience co-occurring dyspnea and pain. Little is known about the relationship between symptom co-occurrence with physical activity (PA) and exercise. Novel diagnostic tools are needed for accurate symptom discrimination. In this secondary analysis, we examined relationships between baseline assessments of pain, dyspnea, objectively measured PA, and exercise capacity in persons with COPD who previously enrolled in three PA studies. Pain was assessed with the bodily pain domain of the Veterans RAND-36 (VR-36), and dyspnea with the modified Medical Research Council (mMRC) scale. Average daily step count was assessed with the Omron HJ-720ITC or FitBit Zip pedometer, and exercise capacity with 6-minute walk test (6MWT). We also conducted a pilot neuroimaging study. Neuroimaging data were acquired on a Siemens 3-Tesla Magnetom Prisma^fit whole-body scanner. Analysis of variance assessed trends in daily step count and 6MWT distance across categories of co-occurring pain and dyspnea. General linear models examined relationships between cortical thickness and resting state functional connectivity (fc) with symptoms and functional status. In 373 Veterans, 98% were male with mean age 70.5± 8.3 years and FEV₁% predicted 59 ± 21%. Compared to those with no co-occurrence of pain and dyspnea, those with co-occurrence walked 1,291–1,444 fewer steps per day and had an 80–85 m lower 6MWT distance. Ten males participated in the pilot neuroimaging study. Predominant findings were that lower cortical thickness and greater fc were associated with higher pain and dyspnea, p<0.05. Greater cortical thickness and lower fc were associated with higher daily step count and 6MWT distance, p<0.05. Regional patterns of associations differed for pain and dyspnea, suggesting that cortical thickness and fc may discriminate symptoms. Co-occurring dyspnea and pain in COPD are associated with significant reductions in PA and exercise capacity. It may be feasible for neuroimaging markers to discriminate between pain and dyspnea.