Publications

BACKGROUND

While exposure to outdoor particulate matter (PM) has been associated with poor asthma outcomes, few studies have investigated the combined effects of outdoor and indoor PM (including secondhand tobacco smoke).

OBJECTIVE

To examine the associations between PM and asthma outcomes.

METHODS

We analyzed data from a cohort of adults with asthma and rhinitis (n=302; 82% both conditions; 13% asthma only; 5% rhinitis alone) including measures of home PM, tobacco smoke exposure (hair nicotine and self-report), ambient PM from regional monitoring, distance to roadway, and season (wet or dry). The outcomes of interest were frequent respiratory symptoms and forced expiratory volume in 1 second (FEV1) below the lower limit of normal (NHANES reference values). Multivariable regression analyses examined the associations (Odds Ratio [OR] and 95% Confidence Interval [95%CI]) between exposures and these outcomes, adjusted by sociodemographic characteristics.

RESULTS

In adjusted analyses of each exposure, the highest tertile of home PM and season of interview were associated with increased odds for more frequent respiratory symptoms (OR=1.64 95%CI: [1.00, 2.69] and OR=1.66 95%CI: [1.09, 2.51]). The highest tertile of hair nicotine was significantly associated with FEV1 below the lower limit of normal (OR=1.80 95%CI: [1.00, 3.25]). In a model including home PM, ambient PM, hair nicotine, and season, only two associations remained strong: hair nicotine with FEV1 below the lower limit of normal and season of measurement (dry, April-October) with increased respiratory symptoms (OR=1.85 95%CI: [1.00, 3.41] and OR=1.54 95%CI: [1.0, 2.37]). When that model was stratified by sex, the highest tertiles of ambient PM and hair nicotine were associated with FEV1 below the lower limit of normal among women (OR=2.23 95%CI: [1.08, 4.61] and OR=2.90 95%CI: [1.32, 6.38]), but not men. The highest tertile of hair nicotine was also associated with increased respiratory symptoms in women but not men (OR=2.38 95%CI: [1.26, 4.49]). When stratified by age, the middle quartile of ambient PM and the highest hair nicotine tertile were associated with increased respiratory symptoms (OR=2.07 95%CI: [1.01, 4.24] and OR=2.55 95%CI: [1.21, 5.36]) in those under 55 but not in the older stratum.

CONCLUSIONS

Exposure to PM from both home and ambient sources is associated with increased symptoms and lower lung function in adults with asthma, although these associations vary by type of PM, the respiratory outcome studied, sex and age.

OBJECTIVE

Improved drug labelling for chronic pill-form medications has been shown to promote patient comprehension, adherence and safety. We extended health literacy principles and included patients' perspectives to improve instructions for: (1) non-pill form, (2) short term, (3) 'as needed,' (4) tapered and (5) escalating dose medications.

SETTING

Participants were recruited via convenience sampling from primary care clinics in Chicago, Illinois and San Francisco, California, USA.

PARTICIPANTS

40 adult, English-speaking participants who reported taking at least one prescription drug in the past 12 months were enrolled in the study.

PRIMARY AND SECONDARY OUTCOMES

Participant opinions, preferences and comprehension of standard and improved medication instructions were assessed during four iterative waves of discussion groups. Brief interviews preceding the discussion groups measured individuals' literacy skills, sociodemographic and health characteristics.

RESULTS

On average, participants were 46 years old, took four medications and reported two chronic health conditions. Patients varied sociodemographically; 40% were men and 33% had limited literacy skills. Patients agreed on the need for simpler terminology and specificity in instructions. Discussions addressed optimal ways of presenting numeric information, indication and duration of use information to promote comprehension and safe medication use. Consensus was reached on how to improve most of the instructions.

CONCLUSIONS

Through this patient-centred approach, we developed a set of health literacy-informed instructions for more challenging medications. Findings can inform current drug labelling initiatives and promote safe and appropriate medication use.