Identifying phenotypes and factors impacting outcomes in older adults with asthma: A research protocol and recruitment results

Abstract

Success in testing research outcomes requires identification of effective recruitment strategies in the targeted population. In this paper, we present the protocol for our NIH-funded study as well as success rates for the various recruitment strategies employed. This longitudinal observational study is: developing a phenotyping algorithm for asthma in older adults, exploring the effects of the asthma phenotype and of volatile organic compounds on asthma control, and developing a predictive model of asthma quality of life. A sub-aim is to characterize barriers to successful medication management in older adults with asthma. Individuals are eligible if they are ≥60 years, have a positive response to at least 1 of 6 asthma screening questions, non-smokers, and demonstrate bronchodilator reversibility or a positive bronchial challenge test with methacholine. Exclusion criteria are smokers who quit <5 years ago or with a >20 pack year smoking history, and those having other chronic pulmonary diseases. Participants (N=190) complete baseline pulmonary function testing, questionnaires, sputum induction, skin prick testing, and have blood drawn for Vitamin D and Immunoglobulin E. Home environmental assessments are completed including 24-hour particulate and volatile organic compound measurements. At 9-months post-baseline, home spirometry, medication assessment, and assessment of asthma quality of life and asthma control are assessed. At 18-months post-baseline, home spirometry, completion of baseline questionnaires, and a home environmental assessment are completed. We have employed multiple recruitment efforts including referrals from clinical offices, no-cost media events, flyers, and ads. The most successful efforts have been referrals from clinical offices and media events.

Advancing the symptom science model with environmental health

“…Environmental exposures during early life can affect the risk of developing acute diseases, such as pneumonia, or chronic diseases, such as diabetes and asthma, at any point across the life span (Landrigan et al, ). In older adults, exposure to air pollution has been associated with increased rates of chronic obstructive pulmonary disease, chronic bronchitis, asthma, and emphysema, mortality, and hospital admissions/emergency‐department visits (Polivka et al, ; Simoni et al, ). In addition, chronic exposure to air pollutants, such as particulate matter and heavy metals, has been linked to hypertension, stroke, Parkinson's disease, Alzheimer's disease, and cancers (Pope, Ezzati, & Dockery, ; Thurston et al, ).…”

CE: Environments & Health: Chemicals in the Home That Can Exacerbate Asthma

“…Inclusion and exclusion criteria . Participants were required to be nonsmokers, to be at least 60 years of age, and to have a confirmed diagnosis of asthma 11. Excluded were current smokers, former smokers who quit less than five years ago or had a smoking history of 20 pack-years or more, those who had a comorbid pulmonary disease or resided in a skilled nursing facility, and those with a prognostic index score of 10 or higher,11 which is predictive of a 42% four-year mortality risk 13…”

“…To determine participants' level of asthma control over the past four weeks, we asked them to complete the five-item ACT. 11,14 Based on their ACT scores, participants' asthma control was categorized as follows 15 :…”

“…We recently conducted a study to determine whether asthma control varied based on older adults' cleaning practices (participant recruitment and data collection procedures are published elsewhere 11 ). Between 2015 and 2020, we collected data on the cleaning practices of older adults with asthma and the cleaning and disinfectant products they used.…”

“…Participants were primarily female, White, college graduates, and retired or unemployed; most had health insurance, owned their own homes, were diagnosed with asthma as adults, and ranged in age from 60 to 96. 11 Data collection. Data were collected at baseline and at nine and 18 months postbaseline.…”