Table 4. Association of outdoor air pollutants with pterygium recurrence after surgery: multivariate logistic regression (n = 1,060).
| Variables | Model 1 Multivariate OR (95% CI, P value) |
Model 2 Multivariate OR (95% CI, P value) |
|---|---|---|
| Air pollution factors (average during 2 years) | ||
| Humidity, % (5% increase) | 1.59 (0.87–2.91, 0.129) | 1.50 (0.82–2.76, 0.191) |
| PM10, µg/m3 (5 µg/m3 increase) | 0.99 (0.67–1.46, 0.971) | 0.93 (0.63–1.37, 0.700) |
| O3, ppm (0.003 ppm increase) | 0.94 (0.63–1.40, 0.749) | 0.92 (0.61–1.39, 0.704) |
| NO2, ppm (0.003 ppm increase) | 1.10 (0.90–1.35, 0.333) | 1.10 (0.89–1.36, 0.375) |
| SO2, ppm (0.003 ppm increase) | 0.42 (0.17–1.05, 0.062) | 0.45 (0.17–1.18, 0.103) |
| Sociodemographic factors | ||
| Age (10-year increase) | 0.94 (0.76–1.15, 0.718) | 0.88 (0.69–1.10, 0.268) |
| Sex (men/women)* | 0.35 (0.20–0.60, < 0.001) | 0.32 (0.18–0.57, < 0.001) |
| Region of residence (urban/rural) | 1.70 (0.61–4.73, 0.308) | 1.54 (0.53–4.51, 0.431) |
| Education level (university or higher/high school or less) | 0.51 (0.11–2.25, 0.370) | 0.57 (0.13–2.51, 0.456) |
| Income level (high/low) | 1.14 (0.65–2.01, 0.638) | 0.87 (0.50–1.51, 0.615) |
| Other factors | ||
| Sun exposure (more than 5 hours a day/less) | NA | 0.75 (0.39–1.43, 0.379) |
| Myopia (+/−)* | NA | 0.44 (0.21–0.91, 0.029) |
Model 1: sociodemographic factors were modeled as covariates; Model 2: sociodemographic factors, sun exposure, and myopia were modeled as covariates.
OR = odds ratio, CI = confidence interval, PM10 = particulate matter with aerodynamic diameter less than 10 µm, O3 = ozone, NO2 = nitrogen dioxide, SO2 = sulfur dioxide, NA = not available.
*Associated with pterygium in multivariate logistic regression.