Treatment setting, demographics impact adherence to biologic regimens for asthma care
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Factors such as administration setting and demographics impacted adherence to biologic treatment among patients with moderate to severe asthma, according to a study published in The Journal of Allergy and Clinical Immunology: In Practice.
Although adherence rates were generally high overall, researchers found that treatment in a clinic setting and higher patient costs tended to lower adherence, whereas specialist access increased adherence.
Hayden Bosworth, PhD, professor and vice chair for education with the department of population health sciences at Duke University School of Medicine, led stakeholders to better understand the relationship between asthma treatment and clinical inertia.
“We identified six barriers to asthma treatment,” Bosworth told Healio. “An important barrier identified was patient/provider communication and the role of patient adherence and provider-appropriate treatment of asthma.”
The study’s findings
Using the Optum Clinformatics Data Mart database of commercially and publicly insured enrollees, the researchers examined the role of patient behaviors and factors on adherence among 3,932 patients with moderate to severe asthma treated with asthma biologics between Jan. 1, 2016, and April 30, 2020.
“Given the introduction of this new class of medications, we realized it would be beneficial to better understand patient adherence with these expensive medications,” Bosworth said.
Researchers categorized patients based on whether they received treatment only in a clinic setting (n = 2,898), only at home (n = 786) or in a mixture of settings (n = 248).
The patients in the clinic-only cohort were relatively younger on average with a higher proportion of men. They also tended to be white, from the Midwest and higher educated, and they reported higher household incomes, commercial insurance and mostly point-of-service health plan types compared with the other cohorts.
Additionally, these patients had better overall health on average, with fewer comorbidities, other prior medications and health care use.
The home and hybrid care patients, however, were relatively older, with at least 70% of them on Medicare insurance. They also had a higher burden of comorbidities and significantly higher patient costs for index biologics or all medications in the previous 6 months.
The clinic-only patients had relatively lower adherence to their biologics treatment — calculated by dividing the number of observed biologic doses administered by the expected number of doses — (0.75; 95% CI, 0.5-1) compared with the home-only and hybrid cohorts (both, 0.83; 95% CI, 0.5-1).
The researchers also found an association between 10-year increases in age and 1% (adjusted RR = 1.01; 05% CI, 1-1.03) higher biologic adherence rates among the clinic-only cohort.
Additional factors associated with higher adherence in the clinic-only subgroup included a complex asthma regimen (aRR = 1.07; 95% CI, 1.03-1.11), any specialist visit during the previous 6 months (aRR = 1.08; 95% CI, 1.02-1.14) and comorbidities such as chronic sinusitis (aRR = 1.05; 95% CI, 1.01-1.09) and depression (aRR = 1.06; 95% CI, 1-1.12).
Among the clinic-only group, the adherence rates of patients with a high school education or less were 5% (aRR = 0.95; 95% CI, 0.91-0.99) lower than those patients with less than a bachelor’s degree.
Plus, patients in the clinic-only group whose household incomes were less than $40,000 a year had 5% (aRR = 1.05; 95% CI, 1-1.1) higher adherence rates compared with those with incomes between $40,000 and $99,000.
Also, each $1,000 in patient costs for the index biologic in the clinic-only group appeared associated with a 2% (aRR = 0.98; 95% CI, 0.96-1) decrease in adherence rates.
Researchers observed differences in adherence by race and ethnicity in the home subgroup, with 16% (aRR = 0.84; 95% CI, 0.72-0.99) lower adherence rates for Black patients and 13% (aRR = 0.87; 95% CI, 0.77-0.99) lower rates for Hispanic patients compared with white patients. Also in this group, patients with Medicare only had 26% (aRR = 0.74; 95% CI, 0.66-0.83) lower adherence rates than patients with commercial insurance.
Yet patients in the home group who had seen any specialist in the previous 6 months (aRR = 1.14; 95% CI, 1-1.29) or who had a respiratory infection (aRR = 1.09; 95% CI, 1-1.18) had higher adherence.
In the hybrid group, patients with unknown income had 19% (aRR = 1.19; 95% CI, 1.01-1.4) higher adherence rates compared with those with incomes between $40,000 and $99,000. Those with dementia had 33% (aRR = 0.67; 95% CI, 0.48-0.95) lower adherence.
Implications of the results
Overall, these trends reveal important factors affecting adherence that clinicians can consider.
“While we confirmed that racial and ethnic disparities in medication adherence continue to be a problem, we think the finding that adherence varied by administration setting, with the clinic-only tending to have lower levels of adherence compared to at-home or hybrid administration, was important,” Bosworth said.
Clinic-based care may have lower levels of adherence due to transportation barriers and potential implicit bias, as some people are offered clinic care instead of alternative administration, Bosworth explained.
“This finding leads one to consider the importance of patient/provider shared decision-making on the preferred mode of administration,” he said.
Also, a subspecialist visit in the 6 months before the onset of biologic therapy, the researchers wrote, corresponded with an 8% to 25% increase in adherence rates irrespective of the administration settings.
This improved adherence with access to a specialist also was surprising, Bosworth said, leading the researchers to conclude that appropriate care coordination is necessary to ensure that patients with moderate to severe asthma get that access.
The study offers several takeaways for doctors, Bosworth added.
“The recognition and treatment of severe asthma continues to be problematic, but specialist access is important to ensure adequate use and adherence to these efficacious but expensive treatments,” Bosworth said.
Better gateways and care coordination are necessary to ensure that patients with moderate to severe asthma who need further treatment get access to these medications, he continued.
“Second, adherence is a problem, along with clinical inertia. But one solution may be better alignment of patient/provider preference for the location of administration of these treatments,” Bosworth said.
Bosworth noted that clinicians can confidently prescribe biologics for at-home use in patients who are deemed capable of self-medicating, as the researchers found a positive association between home treatment and adherence.
Meanwhile, the researchers also found that the barrier to adherence regardless of administration setting represented by patient financial burden highlights the need for policies and strategies to increase patient access to these therapies despite race or socioeconomic status.
“Research focused on efforts to improve asthma biologic adherence are needed and should consider improving specialist access,” Bosworth said. “Research should also focus on better targeting patient subgroups with higher risk of suboptimal adherence.”
For more information:
Hayden Bosworth, PhD, can be reached at boswo001@duke.edu.