Effectiveness of Pollution Monitoring in Clinical Exercise Rehabilitation

EPIC-AIR is a single-site, stratified, blinded, two-arm randomised controlled feasibility trial conducted at University Hospitals of Leicester NHS Trust. Up to 80 participants comprising cardiac rehabilitation patients, pulmonary rehabilitation patients and healthy volunteers will be recruited. Following a 1-week baseline monitoring period, participants will be stratified by participant group (cardiac rehabilitation, pulmonary rehabilitation or healthy volunteer) and randomised 1:1 within strata using a computer-generated allocation sequence via the Sealed Envelope secure web-based system.

All participants will receive a Fitbit Charge 6 and a 12-week progressive walking programme delivered through the P-STEP platform. Participants allocated to the intervention arm will additionally receive real-time local PM2.5, PM10 and NO2 information and adaptive guidance concerning the timing, location, route or intensity of outdoor activity. Participants in the control arm will use the same platform and receive the same exercise guidance but without air-quality information or pollution-related guidance.

The primary outcomes are three co-primary pollutant-specific measures: weekly time-weighted mean modelled ambient PM2.5, PM10 and NO2 concentrations during moderate-to-vigorous physical activity (MVPA). Time-stamped GPS locations recorded during activity will be linked to wearable-derived activity data and contemporaneous modelled air-quality concentrations. These outcomes represent modelled ambient concentrations encountered during recorded activity rather than directly measured personal inhaled dose.

Weekly pollution exposure during the 12-week intervention will be analysed using repeated-measures mixed-effects models accounting for participant clustering, baseline exposure, study week, randomisation stratum, sex and calendar week. The principal treatment contrast will be the adjusted average intervention-control difference across the 12-week post-allocation period. Multiplicity across the three co-primary pollutants will be controlled using the Holm procedure.

The registered secondary outcome is weekly physical activity derived from wrist-worn accelerometry. Additional clinical, physiological and patient-reported outcomes will be explored. Feasibility outcomes include recruitment, retention, adherence, completeness of outcome data and adverse events. A final follow-up assessment will take place 3 months after completion of the 12-week intervention. No participants had been recruited at the time the registry record was revised.

• Progressive Walking Exercise Programme (Other): Participants will receive a progressive, personalised walking exercise programme aimed to increase their weekly levels of physical activity over a 12 week study period.
• Real-time air quality information and guidance (Behavioral): Real-time air quality information and guidance provided by the online platform.

Primary outcomes

• Weekly time-weighted mean modelled ambient PM2.5 concentration during moderate-to-vigorous physical activity [1-week baseline and weekly throughout the 12 week intervention]: Time-stamped GPS/GNSS locations recorded by the P-STEP platform during Fitbit-derived moderate-to-vigorous physical activity (MVPA) will be linked to contemporaneous modelled ambient PM2.5 concentration estimates. Concentrations will be time-weighted across eligible MVPA periods to derive a weekly mean ambient PM2.5 concentration for each participant.
• Weekly time-weighted mean modelled ambient PM10 concentration during moderate-to-vigorous physical activity [1-week baseline and weekly throughout the 12 week intervention]: Time-stamped GPS/GNSS locations recorded by the P-STEP platform during Fitbit-derived moderate-to-vigorous physical activity (MVPA) will be linked to contemporaneous modelled ambient PM10 concentration estimates. Concentrations will be time-weighted across eligible MVPA periods to derive a weekly mean ambient PM10 concentration for each participant.
• Weekly time-weighted mean modelled ambient NO2 concentration during moderate-to-vigorous physical activity [1-week baseline and weekly throughout the 12 week intervention]: Time-stamped GPS/GNSS locations recorded by the P-STEP platform during Fitbit-derived moderate-to-vigorous physical activity (MVPA) will be linked to contemporaneous modelled ambient NO2 concentration estimates. Concentrations will be time-weighted across eligible MVPA periods to derive a weekly mean ambient NO2 concentration for each participant.

Secondary outcomes

• Weekly physical activity (weekly minutes, measured by wrist-worn accelerometry) [1-week baseline and weekly throughout the 12-week intervention]: Mean minutes of moderate to vigorous physical activity measured continuously over the 12-week intervention period using a wrist-worn accelerometer. The comparison will be change from baseline in mean weekly minutes between the air quality information and control arms at 12 weeks.

Sex: All, ages: 18 Years to any, accepts healthy volunteers

Inclusion Criteria:

* Cohort A: Patients with long-term conditions Inclusion criteria for Cohort A are: male or female adults aged ≥18 years; clinical diagnosis of one or more of asthma, COPD, interstitial lung disease (ILD), coronary heart disease (CHD), or heart failure (HF), and signed off for exercise rehabilitation by a clinician; ownership of a GPS-enabled smartphone with internet access; ability to walk outdoors for a minimum of 5 minutes without feeling uneasy or unsteady; availability to complete the 1-week baseline period, 12-week intervention and 3-month post-intervention follow-up within the planned study period; willingness and ability to give informed consent; and willingness to wear a Fitbit device for >70% of the study duration.
* Inclusion criteria for Cohort B are identical to Cohort A, with the exception that participants must have no diagnosis of asthma, COPD, ILD, CHD, or HF.

Exclusion Criteria:

* Exclusion criteria for both cohorts are: diagnosis of dementia, learning disability, severe mental health disorders (excluding depression or anxiety), or epilepsy; receiving palliative care; insufficient English language ability to understand study documentation and use the platform; having been advised not to exercise by a healthcare professional within the past 12 months; currently pregnant; presence of chest pain at rest; and marked unsteadiness when standing or walking.

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• Andre Ng, Ph.D, MD, Principal investigator, University of Leicester