Despite a declining trend, the number of adults in the U.S. who say they did not adhere to their asthma treatment because of costs remains high, according to an observational study.
From 2011-2022, the prevalence of cost-related non-adherence decreased from 23.2% to 13.1%. However, about one in six adults with asthma (17.8%) reported they did not adhere to their asthma medications in the previous year because of cost, Chung-Hsuen Wu, PhD, of Taipei Medical University in Taiwan, and colleagues reported in .
Wu told 鶹ý his team was "very surprised that the cost-related events went down in the past 12 years -- however, cost-related events are still a problem for patients with asthma."
"And you can see from our study that, compared to patients without cost-related non-adherence, patients with cost-related non-adherence ... are more likely to have asthma attacks and ER visits," he added.
Indeed, adults with asthma who reported skipping or delaying medication for their asthma because of cost had significantly higher odds of having asthma attacks (adjusted OR 1.95, 95% CI 1.78-2.13) and emergency room visits for asthma (adjusted OR 1.63, 95% CI 1.44-1.84) compared with patients who did not report cost-related non-adherence.
Nearly has asthma, making it one of the most common chronic diseases, with a high economic and societal burden. Financial hardship is a major factor in high rates of non-adherence to asthma medications, which has ranged from 22%-66% in past estimates. When patients delay or skip doses in an effort to save money, they may be at higher risk for hospitalization.
Patients who were younger and female were significantly more likely to report cost-related non-adherence. People who were non-Hispanic Black, lived in the South, had educational attainment less than high school, lacked health coverage, reported low income, smoked, had poor perceived health, and who were single or lived alone were also more likely to report non-adherence to asthma medication because of cost.
Wu also noted that the "near-poor," who have an income just over the federal poverty level and may not qualify for Medicaid, had the greatest cost-related non-adherence.
Accordingly, co-author Chun-Tse Hung, PharmD, also of Taipei Medical University, told 鶹ý that the decline in this problem in recent years may be due to 2010's Affordable Care Act (ACA) and the expansion of Medicaid, "so the financial burdens [for] some kinds of patients might decrease, so they have less financial burden to receive these medications."
Emily Graul, of Emory University School of Medicine in Atlanta, and Christer Janson, PhD, of Uppsala University in Sweden, emphasized in an the "greater burden" of the problem in the southern U.S.
"These results should be contextualized by history and the present," they wrote. "The legacy of racism and inequality built within healthcare, labor, and unionization policy in the South has contributed to higher proportions of people being uninsured and facing cost-related barriers to healthcare."
They also noted that the recent Inflation Reduction Act's Medicare Drug Price Negotiation Program lowered drug costs for some chronic conditions, but not asthma, adding, "The results of this study beg the question: Should certain asthma medications be part of the next batch of drug negotiations?"
Wu stressed that healthcare providers should consider cost, not just treatment effects, when prescribing asthma medication.
Researchers used data from the 2011 to 2022 National Health Interview Survey (NHIS), which includes information from questionnaires administered by trained interviewers. Adults with current asthma were included. In all, 2,985,882 participants indicated cost-related non-adherence to asthma medication, which was defined as having answered "yes" to any of three questions:
- Did you skip medication doses to save money over the past 12 months?
- Did you take less medication to save money over the past 12 months?
- Did you delay refilling medications to save money over the past 12 months?
To evaluate asthma-related adverse events, researchers used responses to questions about asthma attacks and visits to the emergency room or urgent care because of asthma in the past 12 months. To evaluate factors associated with cost-related medication non-adherence, researchers included covariates like age, sex, race/ethnicity, region, educational level, health insurance, poverty status, work status, and various health indicators.
The authors were limited by NHIS data, which is self-reported, and did not include information on asthma severity. The study design meant that results cannot be interpreted as causal. Researchers also could not include variables reflecting economic indicators, such as the consumer price index. It is also possible that medical compliance related to cost had more to do with other comorbidities and not asthma, as the questions were broad.
Disclosures
The researchers reported no financial conflicts of interest.
Janson disclosed financial relationships with AstraZeneca, Chiesi, GlaxoSmithKline, Novartis, Orion, and Sanofi. Graul had no disclosures.
Primary Source
Thorax
Hung C-T, et al "Cost-related non-adherence to medications among adults with asthma in the USA, 2011-2022" Thorax 2024; DOI: 10.1136/thorax-2024-221778.
Secondary Source
Thorax
Graul EL, Janson C "Cost-related nonadherence to medication among people with asthma in the United States: Findings that reinforce the relevance of history and healthcare reform" Thorax 2024; DOI: 10.1136/thorax-2024-222662.