FCAAIA Notes: Air cleaners have some utility for control of indoor asthma and allergy triggers. They are useful for particulates matter and irritant dusts. They have some utility in reducing indoor mold and animal dander levels. They actually are not that useful for dust mites or pollen that comes in through open windows, both of which are relatively heavy so they settle and do not remain air-borne very long. As far as second-hand smoke goes, there is a 100% effective control measure: Convince your loved ones to stop smoking…..for everyone’s health, including theirs!
(Source: http://www.medscape.org/viewarticle/747596?src=cmemp August 15, 2011 Adapted from Arch Pediatr Adolesc Med. 2011;165:741-748.)
Clinical Context Secondhand smoke exposure is a daily health risk encountered by too many children in the United States, with more than 30% of all children exposed to secondhand smoke in their homes. The prevalence of this problem increases to 40% or more among children living in poverty.
Smoking increases airborne levels of particulate matter (PM) by 25 to 45 µg/m3 vs increases of only 3 to 6 µg/m3 with activities such as indoor sweeping or cooking. It is this nonnicotine PM that particularly increases the risk for asthma symptoms among children with asthma. The current study by Butz and colleagues analyzes the efficacy of both air cleaners and health coaches to reduce PM and asthma symptoms among a cohort of inner-city children with asthma and exposure to secondhand smoke.
Study Synopsis and Perspective Air cleaners significantly reduce PM levels but are not enough to reduce exposure to secondhand smoke in inner-city children with asthma residing with a smoker, a new study has found……
Arlene M. Butz, ScD, MSN, CPNP, with the Division of General Pediatrics at The Johns Hopkins University School of Medicine, in Baltimore, Maryland, and colleagues reported the findings in the August issue of the Archives of Pediatrics & Adolescent Medicine.
……”Despite parental awareness that second-hand smoke exacerbates asthma, 40% to 67% of inner-city children with asthma reside in a household with at least 1 smoker,” the study authors note. According to the researchers, PM concentrations of secondhand smoke exposures have previously been found to be reduced with the use of air cleaners.
The current study sought to test the ability of an air cleaner only (n = 41), an air cleaner plus a health coach (n = 41), or delayed air cleaners (control; n = 44) in reducing PM, air nicotine, and urine cotinine concentrations. The number of symptom-free days was also evaluated.
Eligible children were aged 6 to 12 years, with clinician-diagnosed asthma, symptom frequency, and/or controller medication use signifying persistent asthma. A smoker, who smoked more than 5 cigarettes per day and resided in the home at least 4 days per week, was also present.
Reductions in mean fine and coarse PM (PM2.5 and PM2.5-10) concentrations from baseline to 6 months were significantly higher in both air cleaner groups vs the control group (PM2.5 concentrations, P = .003; and PM2.5-10 concentrations, P = .02 for differences between both air cleaner groups and control).
However, the presence of secondhand smoke, as measured by air nicotine and urine cotinine concentrations, was comparable among the groups. Use of a health coach did not further reduce PM concentrations.
Air cleaner groups, when combined, had a significant increase in symptom-free days during the past 2 weeks (1.36 vs 0.24 symptom-free days for control group children from baseline to follow-up), representing an increase of 14% to 18% symptom-free days, and yielding an additional 33 symptom-free days per year.
“Use of air cleaners in homes of children with asthma was associated with a significant reduction in indoor PM concentrations and increase in symptom-free days,” the study authors note. “However, the reduced indoor PM levels were not sufficiently decreased to meet EPA [Environmental Protection Agency] standards for outdoor air quality,” they add….
- Children eligible for study participation were between the ages of 6 and 12 years and had clinician-diagnosed persistent asthma. All children also had a smoker in the home who smoked more than 5 cigarettes per day.
- Children were randomly selected to 1 of 3 treatment groups: air cleaners only, air cleaners plus a health coach, or a control group (delayed air cleaners).
- The control group received 4 nurse home visits for asthma education. The air cleaner group received similar home visits plus 2 air cleaners in the child’s bedroom.
- The air cleaner plus health coach group received 4 home visits that combined asthma education with motivational interviewing to reduce secondhand smoke exposure, along with the 2 air cleaners.
- The trial period was 6 months. The primary outcome was the concentration of fine and coarse PM in participants’ homes. Researchers also measured caregivers’ assessment of their children’s exposure to secondhand smoke, as well as air nicotine and urine cotinine levels for a more objective assessment. Finally researchers measured asthma morbidity and healthcare utilization by participants.
- 126 families agreed to participate in the trial, and 91.3% of participating families completed questionnaire data at 6 months.
- The mean age of children in the study was 9.1 years, and 54.8% were boys. 96.8% of children were African American, and nearly 90% were enrolled in Medicaid. Nearly two thirds of children had either moderate or severe persistent asthma.
- Baseline characteristics were generally similar in comparing randomly selected groups, but children’s caregivers in the control group smoked more cigarettes vs the other treatment groups.
- Air cleaners were used on most days in these treatment groups.
- Between 98% and 100% of caregivers reported trying to keep their child away from cigarette smoke at both baseline and at 6 months.
- Air cleaners were significantly superior to control therapy in reducing the concentrations of both fine and coarse PM.
- However, air nicotine and urine cotinine concentrations were similar in comparing baseline and 6-month values in all treatment groups.
- Use of the air cleaner was associated with an average increase of 1.36 asthma symptom–free days during the past 2 weeks vs a mean decline of 0.24 symptom-free days in the control group.
- However, air cleaners were not more effective than control treatment in reducing symptom-free nights or healthcare utilization for acute asthma events.
- Although the number of symptom-free days was higher in the health coach plus cleaners group vs the cleaners-only group, this difference was not statistically significant.
- More than 30% of all children in the United States are exposed to secondhand smoke in their homes, with a higher rate among children living in poverty. Smoking increases airborne PM levels substantially more than activities such as indoor sweeping or cooking, and non-nicotine PM can increase the risk for asthma symptoms among children with asthma.
- The current study finds that air cleaners can reduce the concentrations of PM in the homes of smokers and the number of symptom-free days among children with asthma in these homes. However, these cleaners failed to reduce air nicotine levels, children’s urine cotinine levels, or healthcare utilization for acute asthma events. The addition of asthma health coaches did not improve the efficacy of air cleaners.