Background: Asthma is a chronic lung disease characterized by airway hyperresponsiveness leading to reduction in quality of life. Volatile organic compounds (VOCs), easily evaporable chemicals found in fragrances, cleaning chemicals, and personal care products, are known to exacerbate asthma. The home can be a source of asthma triggers, including VOCs, leading to uncontrolled disease. Minimizing triggers in the home is essential for controlling asthma. Given that women are more likely to have greater severity of asthma than men, it is unknown whether there are gender differences in home VOC exposure. The purpose of this project is to examine any differences in VOC levels in the home by gender and education in older adults with asthma.

Methods: In this secondary analysis of a retrospective observational study, older adults ages 60 and above with asthma had VOC levels measured in their homes over a 24-hour period. Participants also completed baseline metrics of lung function and asthma control including forced expiratory volume (FEV-1), asthma control test (ACT), and Fractional Exhaled Nitric Oxide (FeNO). The 19 specific VOCs included in this analysis were detected indoors in 90% of homes or higher.

Results: Participants (N=184) were primarily White (77%), had a mean age at enrollment of 69±6.2 years, and included a female to male ratio of 2.7:1. Almost half (27.8%) were college educated, however 5.4% had less than a high school education. About one-third (33.7%) had an FEV1 percent predicted ≤79%, 36.4% had FeNO ≥25, and 56% had an ACT ≤19. The average of the total VOCs in each home was 68.36±87.37 parts per billion (ppb), the maximum was 603.69 ppb, minimum was 3.41 ppb, and the interquartile range (IQR) was 55.22 ppb. Acetone had the highest mean, median, and IQR of the 19 VOCs across the homes. Males had significantly higher levels of 124-trimethlybenzene in their homes (p= 0.005). Participants with less than a high school education had significantly higher levels of indoor freon113 and of carbon tetrachloride (p=0.019 and p= 0.013, respectively).

Conclusion: Differences in the concentration of specific VOCs in the homes of older adults with asthma by gender and education were identified. These findings may inform education and intervention strategies to reduce residential VOC exposure and improve asthma control in vulnerable populations.