Development and Validation of a Multivariable Exercise Adherence Prediction Model for Patients with COPD: A Prospective Cohort Study

Predicting Response to In-Hospital Pulmonary Rehabilitation in Individuals Recovering From Exacerbations of Chronic Obstructive Pulmonary Disease

BACKGROUND

Predicting the response to pulmonary rehabilitation (PR) could be valuable in defining admission priorities. We aimed to investigate whether the response of individuals recovering from a COPD exacerbation (ECOPD) could be forecasted using machine learning approaches.

METHOD

This multicenter, retrospective study recorded data on anthropometrics, demographics, physiological characteristics, post-PR changes in six-minute walking distance test (6MWT), Medical Research Council scale for dyspnea (MRC), Barthel Index dyspnea (BId), COPD assessment test (CAT) and proportion of participants reaching the minimal clinically important difference (MCID). The ability of multivariate approaches (linear regression, quantile regression, regression trees, and conditional inference trees) in predicting changes in each outcome measure has been assessed.

RESULTS

Individuals with lower baseline 6MWT, as well as those with less severe airway obstruction or admitted from acute care hospitals, exhibited greater improvements in 6MWT, whereas older as well as more dyspnoeic individuals had a lower forecasted improvement. Individuals with more severe CAT and dyspnea, and lower 6MWT had a greater potential improvement in CAT. More dyspnoeic individuals were also more likely to show improvement in BId and MRC. The Mean Absolute Error estimates of change prediction were 44.70m, 3.22 points, 5.35 points, and 0.32 points for 6MWT, CAT, BId, and MRC respectively. Sensitivity and specificity in discriminating individuals reaching the MCID of outcomes ranged from 61.78% to 98.99% and from 14.00% to 71.20%, respectively.

CONCLUSION

While the assessed models were not entirely satisfactory, predictive equations derived from clinical practice data might help in forecasting the response to PR in individuals recovering from an ECOPD. Future larger studies will be essential to confirm the methodology, variables, and utility.

Association of Frailty and Depressive Symptoms With the Establishment of Exercise Habits in Patients Undergoing Outpatient Cardiac Rehabilitation

Objective

To assess whether patients undergoing outpatient cardiac rehabilitation who have frailty and depressive symptoms at discharge are less likely than those without these condition to establish positive exercise habits.

Design

A retrospective cohort study that involved the assessment of frailty and depressive symptoms at the end of a 3-month course of cardiac rehabilitation. Frailty was defined as the patient noting 3 or more items using the criteria of Fried et al, while depressive symptoms were delineated by Patient Health Questionnaire-9 (PHQ-9) scores of 10 or greater.

Setting

General hospital (1048 beds) with outpatient cardiac rehabilitation in a suburb location in Japan.

Participants

344 individuals underwent outpatient cardiac rehabilitation during the January 1, 2019-June 1, 2022, study period. Of these, 48 individuals were excluded because they did not complete the course and 54 were excluded because they lacked outcome data. Finaly, 242 individuals (mean age: 68.2±11.1 years) were analyzed.

Interventions

Not applicable.

Main Outcome Variable

The establishment of an exercise habit defined as exercising at least 2 days per week and 30 minutes per day.

Results

Participants were divided into 4 groups depending upon the presence or absence of frailty and depressive symptoms: non-frail with no reported depressive symptoms (173 subjects), frailty-only (21 subjects), depressive symptoms-only (38 subjects), and frailty and depressive symptoms (10 subjects). Compared with patients who were not depressed and not frail, those with frailty only (odds ratio [OR]: 0.43, 95% confidence interval: 0.21-0.88, P=.02) and those with frailty and depressive symptoms (OR: 0.21, 95% confidence interval: 0.05-0.82, P=.025) had significantly lower ORs for establishing exercise habits. After multivariate adjustment, the OR of establishing an exercise habit was significantly lower in those with only frailty (OR: 0.35, 95% confidence interval: 0.14-0.85, P=.005).

Conclusions

This study, while limited by the small number of subjects with both frailty and depressive symptoms, indicates that interventions to prevent frailty during hospitalization and cardiac rehabilitation may be essential for cardiovascular disease patients with frailty whether or not associated with depressive symptoms.

Measuring Adherence to Pulmonary Rehabilitation: A Prospective Validation Study of the Dutch Version of the Rehabilitation Adherence Measure for Athletic Training (RAdMAT-NL)

Purpose

Measuring exercise adherence is important in patients with chronic obstructive pulmonary disease (COPD). For this, the Rehabilitation Adherence Measure for Athletic Training (RAdMAT) seems to be a promising instrument, and a Dutch version (RAdMAT-NL) is available. The aim of this study was to explore the dimensionality and construct validity of the RAdMAT-NL in patients with COPD. Secondly, we examined whether the items of the RAdMAT-NL could be summed to a single score.

Patients and Methods

This prospective study included 193 patients with COPD from 53 primary physiotherapy practices in The Netherlands and Belgium. Patients and their physiotherapist provided data including the RAdMAT-NL, at one, two, and three months after inclusion. Horn's parallel analysis and exploratory factor analysis (EFA) were used to assess the dimensionality of the RAdMAT-NL. Fit to the dichotomous Rasch model for measurement was used to confirm the unidimensionality of the extracted RAdMAT-NL subscales and total scale. To evaluate construct validity, Spearman correlations with other indicators of adherence were calculated, including SIRAS score, percentage attendance and change in exercise skills.

Results

EFA identified two dimensions of the RAdMAT-NL, "Participation" (13 items) and "Communication" (3 items), explaining 50.8% of the total variance. Rasch analysis confirmed the unidimensionality of the two dimensions. The unidimensional Rasch model was rejected for a summed score of all 16 RAdMAT-NL items. Medium to large significant positive correlations between the RAdMAT-NL subscale participation and different measures of adherence supported its convergent validity.

Conclusion

The RAdMAT-NL exhibited two subscales that fitted the unidimensional Rasch model for objective measurement. Construct validity was supported by convergence with other established measures of adherence.

Feasibility, effectiveness and safety of self-management in pulmonary rehabilitation: a study protocol using a hybrid type 1 effectiveness-implementation design

Background

As population ageing accelerates worldwide, chronic diseases will place an increasing burden on society and healthcare systems. Self-management interventions may become a key strategy for addressing chronic disease burden and healthcare costs, also in pulmonary rehabilitation (PR). One of the challenges here is long-term adherence. Understanding the level of adherence to PR may help inform clinical decision-making to focus more on self-management and less on clinical supervision. For this reason, a prediction model (PATCH) was developed. The presented protocol concerns a study that aims 1. to evaluate the safety and effectiveness of self-management within pulmonary rehabilitation (PR) on health outcomes in patients with chronic obstructive pulmonary disease (COPD), 2. to evaluate the predictive validity of the PATCH tool, and 3. to evaluate feasibility and acceptability of self-management and the PATCH tool by patients and physiotherapists.

Methods and analysis

This is a protocol of a hybrid type 1 effectiveness-implementation design, performed in primary physiotherapy practices in The Netherlands. The aim is to include 108 patients with COPD who have already followed PR for at least six weeks (maintenance stage of PR). According to the Dutch KNGF Guideline COPD, physiotherapists should reduce the number of supervised treatments after the maintenance phase and support self-management. In practice, this does not (always) happen. This protocol is based on implementing guideline advice: clinical supervision will be halved but patients are stimulated to engage in self-management by exercising unsupervised, leading to no change in the total planned exercise frequency. During the supervised sessions physiotherapists will assess and stimulate self-management. At baseline, and after 3, 6, 9 and 12 months, health outcomes (including adherence) will be evaluated as the primary outcome of this study. At each measurement, the physiotherapist will decide on the basis of individual scores whether the patient needs more clinical supervision or not. Secondary outcomes are the discriminatory power of the PATCH tool (can patients be correctly classified as adherent or non-adherent), and feasibility and acceptability of self-management and the PATCH tool by patients and physiotherapists. Questionnaires and semi-structured interviews will be used for assessment of the outcomes.Trial registration number: METc 2023/074.