A randomized trial of a one-time pest intervention: impact on childhood asthma outcomes

Effect of School Integrated Pest Management or Classroom Air Filter Purifiers on Asthma Symptoms in Students With Active Asthma: A Randomized Clinical Trial

IMPORTANCE

School and classroom allergens and particles are associated with asthma morbidity, but the benefit of environmental remediation is not known.

OBJECTIVE

To determine whether use of a school-wide integrated pest management (IPM) program or high-efficiency particulate air (HEPA) filter purifiers in the classrooms improve asthma symptoms in students with active asthma.

DESIGN, SETTING, AND PARTICIPANTS

Factorial randomized clinical trial of a school-wide IPM program and HEPA filter purifiers in the classrooms was conducted from 2015 to 2020 (School Inner-City Asthma Intervention Study). There were 236 students with active asthma attending 41 participating urban elementary schools located in the Northeastern US who were randomized to IPM by school and HEPA filter purifiers by classroom. The date of final follow-up was June 20, 2020.

INTERVENTIONS

The school-wide IPM program consisted of application of rodenticide, sealing entry points, trap placement, targeted cleaning, and brief educational handouts for school staff. Infestation was assessed every 3 months, with additional treatments as needed. Control schools received no IPM, cleaning, or education. Classroom portable HEPA filter purifiers were deployed and the filters were changed every 3 months. Control classrooms received sham HEPA filters that looked and sounded like active HEPA filter purifiers. Randomization was done independently (split-plot design), with matching by the number of enrolled students to ensure a nearly exact 1:1 student ratio for each intervention with 118 students randomized to each group. Participants, investigators, and those assessing outcomes were blinded to the interventions.

MAIN OUTCOMES AND MEASURES

The primary outcome was the number of symptom-days with asthma during a 2-week period. Symptom-days were assessed every 2 months during the 10 months after randomization.

RESULTS

Among the 236 students who were randomized (mean age, 8.1 [SD, 2.0] years; 113 [48%] female), all completed the trial. At baseline, the 2-week mean was 2.2 (SD, 3.9) symptom-days with asthma and 98% of the classrooms had detectable levels of mouse allergen. The results were pooled because there was no statistically significant difference between the 2 interventions (P = .18 for interaction). During a 2-week period, the mean was 1.5 symptom-days with asthma after use of the school-wide IPM program vs 1.9 symptom-days after no IPM across the school year (incidence rate ratio, 0.71 [95% CI, 0.38-1.33]), which was not statistically significantly different. During a 2-week period, the mean was 1.6 symptom-days with asthma after use of HEPA filter purifiers in the classrooms vs 1.8 symptom-days after use of sham HEPA filter purifiers across the school year (incidence rate ratio, 1.47 [95% CI, 0.79-2.75]), which was not statistically significantly different. There were no intervention-related adverse events.

CONCLUSIONS AND RELEVANCE

Among children with active asthma, use of a school-wide IPM program or classroom HEPA filter purifiers did not significantly reduce symptom-days with asthma. However, interpretation of the study findings may need to consider allergen levels, particle exposures, and asthma symptoms at baseline.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02291302.

A randomized controlled trial of a community health worker delivered home-based asthma intervention to improve pediatric asthma outcomes

OBJECTIVE

The objective of this study was to evaluate the effects of using Community Health Workers (CHWs) to deliver the home-based Wee Wheezers asthma education program on asthma symptoms among children with persistent asthma.

METHODS

In this randomized controlled trial of 151 children aged 2-9 years with persistent asthma, we assigned 75 to the intervention and 76 to the control. The primary outcome was caregiver-reported asthma symptom days. Secondary outcomes included asthma-related healthcare utilization, caregivers' asthma knowledge, illness perception and management behaviors, MDI-spacer administration technique, and home environmental triggers. Outcomes were collected at baseline, 3, 6, 9 and 12 months. A repeated measurements analytic approach with generalized estimating equations was used. To account for missing data, multiple imputation methods were employed.

RESULTS

At 3 and 6 months, improvement in symptom days was not significantly different between groups. However, at 9 and 12 months, the reduction in asthma symptom days was 2.15 and 2.31 days more respectively for those in the intervention group compared to the control. Improvements in MDI-spacer technique, knowledge and attitudes were significant throughout follow-up. Improvement in habits regarding MDI use was significant at 3 and 6 months, and asthma routines were improved at 3 months. However, there was no change in asthma-related healthcare utilization or home environmental triggers.

CONCLUSION

Using CHWs to deliver a home-based asthma education program to caregivers of children with persistent asthma led to improvements in symptom days and several secondary outcomes. Expanding the use of CHWs to provide home-based interventions can help reduce disparities in children's health outcomes.