The short-term effect of particulate matter on cardiorespiratory drug prescription, as a proxy of mild adverse events
AbstractIntroduction and aims
The association between particulate matter < 10 μm in aerodynamic diameter (PM10) and mild disease episodes, not leading to hospitalization or death, has been rarely investigated.Introduction and aims
We studied the short-term effect of PM10 on purchases of specific cardiorespiratory medications, as proxies of mild episodes, in 7 small- and medium-sized cities of Northern Italy, during 2005–2006.Materials and methods
We extracted information on purchased prescriptions from healthcare administrative databases, and we obtained daily PM10 concentrations from fixed monitoring stations. We applied a time-stratified case-crossover design, using the time-series of antidiabetic drugs purchases to control for confounding due to irregularities in daily purchase frequencies.Results
During the warm season, we estimated a delayed (lags 2–6) increased risk of buying glucocorticoid (4.53%, 95% Confidence Interval (CI): 2.62, 6.48) and adrenergic inhalants (1.66%, 95% CI: 0.10, 3.24), following an increment (10 μg/m3) in PM10 concentration. During the cold season, we observed an immediate (lags 0–1) increased risk of purchasing antiarrhythmics (0.76%; 95% CI: 0.16, 1.36) and vasodilators (0.72%; 95% CI: 0.30, 1.13), followed by a risk reduction (lags 2–6), probably due to harvesting.Conclusions
Focusing on drug purchases, we reached sufficient statistical power to study PM10 effect outside large urban areas and conclude that short-term increments in PM10 concentrations might cause mild cardiorespiratory disease episodes.