Table 2.
Recent Studies of High Ambient Temperature and Mortality Examining Air Pollutants as Potential Confounders and/or Effect Modifiers
| Reference | Study location | Method | Exposure | Causes of death | Result |
|---|---|---|---|---|---|
| Basu 2008 [6] | 9 California counties, May to September 1999-2003 | Time-series and case-crossover | Same day mean apparent temperature; daily mean O3, also PM2.5, PM10, NO2, CO, SO2, lag 0 for PM, lag01 for gases | All-cause mortality | Confounders: none found Effect modifiers: none found |
| Bell 2008 [15] | Sao Paulo, Brazil, Santiago, Chile and Mexico City, Mexico, 1998-2002 | Case-crossover | Same day apparent temperature compared with days at 75th percentile, same day lag O3, same-day lag PM10 except Santiago lag 1 PM10 | All-cause daily mortality | Confounders: O3, PM10 Effect modifiers: not studied |
| McMichael 2008 [45] | Delhi, Monterrey, Mexico City, Chiang Mai, Bangkok, Salvador, Sao Paulo, Santiago, Cape Town, Ljubljana, Bucharest, Sofia, 2 to 5-year series (1991-1999) | Time-series | Daily maximum threshold (16°C-31°C) temperature, relative humidity, precipitation data, PM10, BS, or TSP | All-cause mortality | Confounders: none found Effect modifiers: not studied |
| Ren 2008 [22] | US 95 NMMAPS counties, June to September 1987-2000 | Time-series | Daily maximum temperature (same-day, lag 1), maximum hourly O3 | CVD mortality | Confounders: not studied Effect modifier: O3 |
| Vaneckova 2008a [46] | Sydney, Australia, October to March 1993-2001 | Time-series | Temporal Synoptic Index (TSI) on the highest 10% mortality days, O3, PM10 | All-cause, circulatory, cerebrovascular | Confounders: O3 on warm, humid days and PM10 on hot, dry days Effect modifiers: not studied |
| Vaneckova 2008b [19] | Sydney, Australia, October to March 1993-2004 | Time-series | Daily maximum temperature, maximum O3 | Underlying and associated causes of death | Confounders: O3, PM10 Effect modifiers: not studied |
| Zanobetti and Schwartz 2008 [7] | 9 U.S. counties, May to September 1999-2002 | Time series and case-crossover | Daily apparent temperature (minimum, mean, maximum); daily mean O3, PM2.5 | All-cause mortality | Confounders: none found Effect modifiers: none found |
| Kolb 2007 [32] | Montreal, Canada 1984-1993 | Case-crossover | Mean daily and maximum temperature, barometric pressure, relative humidity, adjusted for O3 and both NO2 and O3 | Daily all-cause mortality | Confounders: none found Effect modifiers: not studied |
| Medina-Ramon 2007 [21] | 50 US cities in cold (November to March) and warm (May to September) seasons | Case-crossover | Binary variable as extreme temperature and continuous; O3 | All-cause and CVD mortality | Confounder: O3 Effect modifiers: not studied |
| Filleul 2006 [23] | 9 French cities, all year and heat wave August 2003 | Time-series | Minimum and maximum temperature, 8-hour maximum O3 | Daily all-cause mortality | Confounders: not studied Effect modifier: O3 for some cities |
| Ren 2006 [51] | Brisbane, Australia (all year January 1996 to December 2001) | Time-series | Minimum temperature, daily PM10 as modifier | Cardiorespiratory mortality | Confounders: not studied Effect modifier: PM10 |
| Stafoggia 2006 [16] | Bologna, Milan, Rome, Turin, 1997-2003 | Case-crossover | 30°C mean apparent temperature (lag01) relative to 20°C, O3 | All-cause mortality | Confounders: none found Effect modifiers: not studied |
| Basu 2005 [5] | 20 US metropolitan areas, seasonal analysis 1992 | Time series (and case-crossover | Mean daily temperature per 10°F adjusted for dew point temperature; daily O3 | Individual and daily cardiorespiratory mortality | Confounders: PM10 in summer Effect modifiers: not studied |
| O'Neill 2005 [18] | Mexico City (1996-98) and Monterrey (1996-99) |
Time series; % change |
Heat (35-36°C for Monterrey), mean temperature (25°C Monterrey, 15°C Mexico City), daily O3 | Daily all-cause mortality | Confounders: O3 and PM10 on hot days Effect modifiers: not studied |
| Rainham and Smoyer-Tomic 2003 [17] | Toronto, May 1 to September 30, 1980-1996 | Time-series; relative risk (RR) | Humidex, O3, also CO, NO2, SO2 | Daily all-cause mortality | Confounders: none found Effect modifiers: not studied |
| Pattenden 2003 [49] | Sofia, Bulgaria (1996-1999) and London, England (1993-1996) | Time-series; % change |
Daily weather (2-day mean) and PM (black smoke for London and total suspended particulates for Sofia) | Daily all-cause mortality | Confounders: none found Effect modifiers: not studied |