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Table 1 Descriptive statistics of the cohort and PM2.5 O3, and NO2 exposure, with Cox proportional hazard ratios

From: Low concentrations of fine particle air pollution and mortality in the Canadian Community Health Survey cohort

    95% CI       
Covariate Person-yearsa HR Lower Upper PM2.5 S.D. O3 S.D. NO2 S.D.
All 4,452,700 5.9 2.0 36.0 7.5 8.6 5.9
Sex
 Male 1,995,100 5.9 2.0 35.9 7.6 8.5 5.9
 Female 2,457,600 6.0 2.0 36.0 7.5 8.6 5.9
Age group (years)
 25 to 29 381,100 5.9 2.0 35.7 7.6 8.8 5.9
 30 to 39 869,300 5.9 2.0 35.9 7.7 8.7 5.9
 40 to 49 887,000 5.9 2.0 35.8 7.6 8.7 6.0
 50 to 59 918,100 5.8 2.0 35.8 7.4 8.2 5.7
 60 to 69 753,800 5.9 2.0 36.2 7.3 8.3 5.8
 70 to 79 497,100 6.1 2.1 36.4 7.4 8.9 6.1
 80 to 89 146,200 6.2 2.1 36.3 7.6 9.6 6.3
Immigrant status
 Non-immigrants 3,945,800 1.00 5.8 2.0 35.7 7.4 8.1 5.6
 In Canada for 30+ years 317,900 0.86 0.83 0.88 6.8 2.1 38.5 8.0 11.2 6.5
 In Canada for 20–29 years 92,300 0.74 0.68 0.80 7.0 2.0 37.4 8.0 13.2 7.0
 In Canada for 10–19 years 96,800 0.62 0.56 0.69 7.2 1.9 37.6 7.7 14.5 7.0
Visible minority identity
 Not a visible minority 4,119,200 1.00 5.9 2.0 36.1 7.4 8.4 5.7
 Visible Minority 244,900 0.89 0.84 0.93 6.6 2.1 34.9 8.9 12.8 7.2
 Missing (dummy variable) 88,600 1.48 1.37 1.59 4.9 1.6 31.7 8.3 6.5 4.3
Indigenous identity
 Non-Indigenous or not stated 4,295,500 1.00 6.0 2.0 36.2 7.4 8.6 5.9
 Indigenous 146,000 1.58 1.50 1.67 4.9 1.7 30.3 8.8 6.9 4.7
 Missing (dummy variable) 11,300 1.16 0.99 1.35 5.6 1.8 35.0 7.5 8.2 5.6
Marital status
 Married or Common-law 2,823,000 1.00 5.8 2.0 36.1 7.6 8.1 5.5
 Separated, Widowed, or Divorced 945,100 1.42 1.39 1.45 6.1 2.1 36.1 7.5 9.1 6.2
 Single 681,400 1.57 1.52 1.62 6.2 2.1 35.4 7.5 9.8 6.8
 Missing (dummy variable) 3200 1.58 1.20 2.07 5.9 1.9 34.5 8.0 9.4 6.1
Educational attainment
 No high school diploma 980,900 1.00 5.7 2.1 35.2 7.5 7.8 5.8
 High School 757,200 0.82 0.80 0.84 6.0 2.0 36.6 7.7 8.6 5.8
 Any post-secondary 1,926,400 0.77 0.75 0.78 5.9 2.0 36.0 7.5 8.4 5.7
 University 752,100 0.55 0.54 0.57 6.2 2.0 36.4 7.4 10.1 6.5
 Missing (dummy variable) 36,000 0.98 0.91 1.06 5.9 2.0 35.6 7.7 8.8 5.8
Employment status
 Employed 2,701,800 1.00 5.9 2.0 36.0 7.6 8.7 5.8
 Unemployed 115,100 1.67 1.54 1.82 5.8 2.1 34.9 7.7 8.4 6.3
 Not in work force 1,630,100 2.02 1.96 2.08 6.0 2.1 36.0 7.4 8.5 6.0
 Missing (dummy variable) 5800 1.62 1.24 2.12 5.5 1.8 34.0 7.2 8.8 5.4
Income quintile
 Q1 (lowest income) 788,200 1.00 6.1 2.1 35.6 7.4 9.2 6.5
 Q2 788,700 0.76 0.74 0.78 6.0 2.0 36.1 7.4 8.7 6.1
 Q3 808,500 0.64 0.62 0.66 6.0 2.0 36.3 7.4 8.5 5.8
 Q4 828,500 0.53 0.52 0.55 5.9 2.0 36.2 7.5 8.4 5.7
 Q5 (highest income) 909,000 0.44 0.43 0.46 5.7 1.9 35.9 7.7 8.2 5.5
 Missing (dummy variable) 329,800 0.74 0.72 0.77 5.8 2.0 35.5 8.0 8.6 5.8
Alcohol consumption
 Never drinker 392,400 1.00 5.8 2.0 35.8 7.3 8.0 5.9
 Occasional drinker 840,300 0.84 0.81 0.86 5.8 2.0 35.7 7.6 8.3 5.8
 Regular drinker, binging unknown 1,332,300 0.64 0.62 0.66 6.1 2.0 36.7 7.3 9.1 6.0
 Regular, non-binge drinker 1,169,600 0.69 0.67 0.72 5.8 2.0 35.8 7.5 8.4 5.7
 Regular, binge drinker 260,400 1.08 1.03 1.14 5.9 2.0 35.8 7.8 8.1 5.8
 Former drinker 447,500 1.10 1.07 1.14 5.9 2.1 35.3 8.0 8.8 6.2
 Missing (dummy variable) 10,200 0.93 0.81 1.07 5.6 1.9 34.8 7.5 8.5 5.5
Smoking behaviours
 Never smoker 1,293,700 1.00 6.0 2.0 36.4 7.5 9.0 6.1
 Occasional smoker 177,200 2.11 2.00 2.23 6.0 2.0 35.6 7.7 9.0 6.3
 Smoke under 10 cigarettes/day 263,000 2.45 2.35 2.55 5.9 2.1 35.3 7.9 8.7 6.2
 Smoke 11–20 cigarettes /day 398,900 2.76 2.66 2.86 5.9 2.0 35.6 7.7 8.3 5.8
 Smoke 20+ cigarettes /day 255,300 3.69 3.55 3.82 5.9 2.1 36.0 7.6 8.2 5.9
 Former smoker 2,058,700 1.32 1.29 1.35 5.9 2.0 35.9 7.4 8.4 5.8
 Missing (dummy variable) 6100 1.51 1.26 1.80 5.7 1.8 35.6 7.4 8.3 5.7
Fruit and vegetable consumption
 Under 5 servings/day 2,411,900 1.00 5.9 2.0 36.0 7.7 8.6 5.9
 5–10 servings/day 1,450,300 0.82 0.80 0.83 6.0 2.0 36.6 7.5 8.8 5.9
 10+ servings/day 132,700 0.82 0.77 0.87 6.1 2.0 36.6 7.5 8.9 6.0
 Missing (dummy variable) 457,900 1.19 1.16 1.23 5.6 1.9 33.6 5.8 7.9 6.1
Leisure exercise frequency
 Active 1,005,700 1.00 5.9 2.0 36.1 7.6 8.6 5.7
 Moderate 1,123,600 1.10 1.07 1.14 5.9 2.0 36.1 7.5 8.6 5.8
 Inactive 2,224,700 1.70 1.65 1.74 5.9 2.0 35.9 7.5 8.5 6.0
 Missing (dummy variable) 98,700 2.49 2.39 2.60 5.9 2.1 35.2 7.8 9.0 6.2
Body mass index (BMI)
 Normal weight (18.5–24.9) 1,425,400 1.00 6.1 2.0 36.1 7.4 9.1 6.2
 Overweight (25.0–29.9) 1,671,700 0.81 0.80 0.83 5.9 2.0 36.0 7.5 8.5 5.8
 Obese 1 (30.0–34.9) 800,500 0.93 0.90 0.95 5.8 2.0 35.9 7.6 8.1 5.6
 Obese 2 (≥ 35) 355,300 1.33 1.28 1.37 5.7 2.0 35.7 7.7 7.9 5.5
 Underweight (< 18.5) 57,700 2.13 2.00 2.26 6.2 2.1 36.0 7.4 9.7 6.5
 Missing 142,200 1.61 1.53 1.68 5.8 2.0 35.8 7.8 8.2 5.5
Residential Instability
 Q1 (lowest marginalization) 993,500 1.00 5.3 1.8 36.9 7.8 7.1 4.8
 Q2 1,231,300 0.98 0.95 1.00 5.6 1.9 36.7 7.9 7.1 4.8
 Q3 957,500 0.98 0.95 1.01 5.9 2.0 34.6 7.7 8.6 5.5
 Q4 780,100 0.96 0.93 0.99 6.5 2.0 35.7 6.8 10.0 6.2
 Q5 (highest marginalization) 490,300 1.04 1.01 1.07 7.2 1.9 35.5 6.1 13.0 7.6
Dependency
 Q1 (lowest marginalization) 701,400 1.00 5.7 1.9 33.4 8.7 10.0 6.2
 Q2 601,900 0.96 0.92 0.99 6.1 1.9 35.8 7.3 9.9 6.0
 Q3 602,400 0.92 0.89 0.95 6.3 2.1 37.4 7.5 9.7 6.1
 Q4 945,800 0.90 0.87 0.93 6.2 2.1 37.6 7.5 8.6 5.8
 Q5 (highest marginalization) 1,601,300 0.88 0.86 0.91 5.7 2.0 35.7 6.7 7.0 5.3
Material deprivation
 Q1 (lowest marginalization) 713,600 1.00 6.0 1.8 37.7 7.4 9.8 5.2
 Q2 777,700 1.03 1.00 1.06 6.2 1.9 38.0 8.0 9.4 5.4
 Q3 897,400 1.04 1.01 1.07 6.2 1.9 37.5 7.3 8.8 5.5
 Q4 783,800 1.08 1.04 1.11 6.2 2.1 35.7 7.5 9.2 6.3
 Q5 (highest marginalization) 1,280,200 1.15 1.12 1.19 5.3 2.0 32.9 6.4 6.8 6.2
Ethnic concentration
 Q1 (lowest marginalization) 1,839,100 1.00 5.2 1.7 35.7 6.9 5.9 3.8
 Q2 1,211,600 1.02 1.00 1.04 6.0 2.0 36.7 8.0 8.0 4.8
 Q3 749,900 1.01 0.99 1.04 6.3 2.0 35.5 7.8 10.1 5.7
 Q4 409,500 1.04 1.00 1.07 7.0 2.1 35.7 8.2 14.2 6.9
 Q5 (highest marginalization) 242,600 0.98 0.94 1.02 7.7 1.7 36.4 7.5 17.7 6.2
Census Metropolitan Area/Census Agglomeration size
 Not applicable (non-CMA/CA) 1,485,900 1.00 4.7 1.3 33.9 7.1 4.9 2.7
 10,000–29,999 355,900 1.03 0.99 1.06 5.0 1.3 31.6 7.9 6.0 3.1
 30,000–99,999 570,900 1.03 1.00 1.06 5.8 1.8 36.6 6.9 7.1 3.3
 100,000–499,999 872,600 1.00 0.98 1.03 6.8 2.2 39.5 8.0 8.9 4.6
 500,000-1,499,999 506,400 0.94 0.91 0.97 6.7 1.7 36.5 6.2 13.2 6.2
  > 1,500,000 661,000 0.91 0.89 0.94 7.5 1.7 37.4 6.5 15.5 6.9
Urban form
 Active urban core 304,800 1.00 7.6 1.9 36.7 7.1 14.5 7.1
 Transit-reliant suburb 179,500 0.98 0.93 1.04 7.8 1.7 36.7 7.1 16.1 7.4
 Car-reliant suburb 1,242,700 0.81 0.78 0.84 7.0 1.9 38.3 7.0 12.1 6.0
 Exurban 216,400 0.83 0.78 0.87 5.5 1.6 38.7 7.0 6.8 3.6
 Non-CMA/CA 2,509,400 0.93 0.90 0.96 5.1 1.6 34.4 7.5 5.7 3.2
Airshed
 East Central 2,041,500 1.00 7.0 2.1 41.3 6.0 9.9 6.6
 Northern 117,800 1.18 1.11 1.27 3.9 1.2 26.0 7.0 4.7 2.6
 Southern Atlantic 711,700 1.11 1.08 1.13 4.4 1.0 30.7 3.1 3.9 2.6
 Prairie 666,900 1.00 0.97 1.02 5.2 1.4 34.1 5.7 9.5 4.9
 West Central 397,100 1.07 1.03 1.10 4.9 1.1 31.3 5.0 8.0 4.9
 Western 517,600 1.04 1.01 1.07 5.7 1.5 30.6 5.9 9.8 5.0
  1. Columns 6, 8, and 10 are mean values
  2. anumbers rounded to the nearest 100 for confidentiality