Table 3.
Adjusted Odds of Suicide Associated With Interquartile-Range Increases in PM2.5 and Nitrogen Dioxide Concentrations, by Lag and Subgroup, Salt Lake County, Utah, 2000–2010
| Subgroup and Air Pollutant | Lag or Lag Period |
|||||||
|---|---|---|---|---|---|---|---|---|
| Lag Day 2 |
Lag Day 3 |
Cumulative Lag 2 |
Cumulative Lag 3 |
|||||
| ORa | 95% CI | ORa | 95% CI | ORa | 95% CI | ORa | 95% CI | |
| Sex | ||||||||
| Male | ||||||||
| PM2.5 | 1.06 | 1.01, 1.12 | 1.06 | 1.01, 1.10 | 1.05 | 0.99, 1.11 | 1.06 | 1.00, 1.13 |
| NO2 | 1.18 | 1.04, 1.34 | 1.19 | 1.06, 1.33 | 1.16 | 0.98, 1.36 | 1.25 | 1.07, 1.47 |
| Female | ||||||||
| PM2.5 | 1.00 | 0.91, 1.09 | 0.95 | 0.87, 1.04 | 0.99 | 0.89, 1.11 | 0.97 | 0.87, 1.09 |
| NO2 | 0.97 | 0.76, 1.23 | 1.04 | 0.83, 1.29 | 1.03 | 0.75, 1.40 | 1.04 | 0.77, 1.41 |
| Age, years | ||||||||
| ≤35 | ||||||||
| PM2.5 | 1.02 | 0.95, 1.09 | 1.03 | 0.97, 1.09 | 1.04 | 0.96, 1.13 | 1.04 | 0.96, 1.13 |
| NO2 | 1.08 | 0.91, 1.28 | 1.06 | 0.90, 1.24 | 1.21 | 0.96, 1.51 | 1.20 | 0.96, 1.51 |
| 36–64 | ||||||||
| PM2.5 | 1.07 | 1.01, 1.15 | 1.03 | 0.97, 1.09 | 1.03 | 0.95, 1.11 | 1.03 | 0.96, 1.12 |
| NO2 | 1.15 | 0.97, 1.37 | 1.20 | 1.05, 1.39 | 1.01 | 0.82, 1.25 | 1.13 | 0.92, 1.39 |
| ≥65 | ||||||||
| PM2.5 | 1.06 | 0.91, 1.24 | 1.09 | 0.96, 1.24 | 1.00 | 0.81, 1.22 | 1.05 | 0.86, 1.28 |
| NO2 | 1.16 | 0.78, 1.72 | 1.36 | 0.96, 1.94 | 1.26 | 0.75, 2.13 | 1.51 | 0.88, 2.58 |
| Season | ||||||||
| Spring | ||||||||
| PM2.5 | 1.18 | 1.01, 1.38 | 1.08 | 0.94, 1.25 | 1.25 | 1.00, 1.56b | 1.28 | 1.01, 1.61 |
| NO2 | 1.23 | 0.98, 1.53 | 1.17 | 0.95, 1.45 | 1.28 | 0.92, 1.77 | 1.41 | 1.00, 1.99b |
| Summer | ||||||||
| PM2.5 | 1.05 | 0.86, 1.27 | 0.99 | 0.80, 1.21 | 1.02 | 0.79, 1.33 | 1.02 | 0.76, 1.35 |
| NO2 | 1.14 | 0.87, 1.50 | 1.06 | 0.83, 1.36 | 1.01 | 0.71, 1.44 | 1.05 | 0.73, 1.51 |
| Fall | ||||||||
| PM2.5 | 1.08 | 0.95, 1.22 | 1.05 | 0.94, 1.18 | 1.08 | 0.94, 1.25 | 1.09 | 0.94, 1.26 |
| NO2 | 1.08 | 0.87, 1.33 | 1.31 | 1.04, 1.65 | 1.17 | 0.87, 1.57 | 1.30 | 0.98, 1.73 |
| Winter | ||||||||
| PM2.5 | 1.00 | 0.93, 1.07 | 1.01 | 0.96, 1.07 | 0.95 | 0.87, 1.04 | 0.97 | 0.89, 1.06 |
| NO2 | 1.03 | 0.83, 1.28 | 1.04 | 0.88, 1.23 | 0.94 | 0.71, 1.26 | 0.98 | 0.75, 1.29 |
| Transition period (spring/fall) | ||||||||
| PM2.5 | 1.11 | 1.01, 1.22 | 1.06 | 0.98, 1.16 | 1.10 | 0.99, 1.23 | 1.11 | 0.99, 1.25 |
| NO2 | 1.15 | 0.99, 1.33 | 1.24 | 1.07, 1.44 | 1.22 | 0.99, 1.51 | 1.35 | 1.09, 1.66 |
| Stable period (summer/winter) | ||||||||
| PM2.5 | 1.02 | 0.96, 1.08 | 1.02 | 0.97, 1.07 | 0.99 | 0.92, 1.07 | 1.00 | 0.93, 1.08 |
| NO2 | 1.09 | 0.93, 1.29 | 1.06 | 0.92, 1.22 | 1.02 | 0.82, 1.25 | 1.05 | 0.85, 1.30 |
| Method of deathc | ||||||||
| Violent | ||||||||
| PM2.5 | 1.07 | 1.02, 1.12 | 1.06 | 1.01, 1.10 | 1.06 | 1.00, 1.12b | 1.07 | 1.01, 1.13 |
| NO2 | 1.16 | 1.02, 1.32 | 1.20 | 1.06, 1.35 | 1.17 | 0.99, 1.37 | 1.27 | 1.07, 1.50 |
| Nonviolent | ||||||||
| PM2.5 | 1.02 | 0.93, 1.11 | 0.99 | 0.91, 1.07 | 1.00 | 0.90, 1.13 | 1.00 | 0.89, 1.11 |
| NO2 | 1.09 | 0.86, 1.38 | 1.08 | 0.88, 1.33 | 1.09 | 0.80, 1.50 | 1.13 | 0.83, 1.52 |
Abbreviations: CI, confidence interval; NO2, nitrogen dioxide; OR, odds ratio; PM2.5, particulate matter with an aerodynamic diameter ≤2.5 μm.
a Adjusted for average daily sunlight during the previous 3 days, daily mean temperature, daily mean temperature for the previous 3 days, mean dew point temperature, mean dew point temperature for the previous 3 days, daily mean air pressure, and daily mean air pressure for the previous 3 days.
b 95% CI excluded 1.00 before rounding to 2 decimal places.
c Nonviolent methods of death included drug overdose, drowning, poisoning, and gas; all other methods of death were categorized as violent.