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Table 1 Descriptive statistics showing covariates and exposures in the cohort of non-Alzheimer’s dementia and Parkinson’s disease, 45–85 years old, 1994–1998

From: Road proximity, air pollution, noise, green space and neurologic disease incidence: a population-based cohort study

LevelCovariates Non-Alzheimer’s dementia (N = 633949)Parkinson’s disease (N = 634432)
Case (N = 13170)Non-case (N = 620779)Case (N = 4201)Non-case (N = 630231)
IndividualAgeMinimum45454545
Median76577258
Maximum83838383
Interquartile9181218
 Count%Count%Count%Count%
SexFemale778559.132596752.5194146.233225552.7
Male538540.929481247.5226053.829797647.3
ComorbidityaNo668450.745439973.2231955.245899672.8
Yes648649.316638026.8188244.817123527.2
NeighborhoodHousehold incomeLowest342626.011300218.296823.011556618.4
Low271320.611350518.385720.411544118.3
Middle230717.512212219.777218.412378119.6
Upper middle232317.613084320.174517.713250921.0
Upper240118.314130723.785920.514293422.7
EducationLess than secondary185114.08050112.957413.78188313.0
Secondary357527.216815627.1110826.417075627.1
Post-secondary774458.837212260.0251959.937759259.9
Chinese<10% of population in Neighborhood632548.029544247.6202448.230003547.6
> 10% of population in Neighborhood684552.032533752.4217751.833019652.4
South Asian<10% of population in Neighborhood653849.729483447.5201948.129960847.5
> 10% of population in Neighborhood663250.332594552.5218251.933062352.5
Visible minority<10% of population in Neighborhood1029378.248714278.5330578.749447778.5
> 10% of population in Neighborhood287721.813363721.589621.313575421.5
Exposures  Non-Alzheimer’s dementia (N = 633949)Parkinson’s disease (N = 634432)
Case (N = 13170)Non-case (N = 620779)Case (N = 4201)Non-case (N = 630231)
Road proximity  Count%Count%Count%Count%
Highway <50mNo1289697.960759497.9410497.727974197.9
 Yes2742.1131852.1972.3133752.1
Highway <150mNo1241794.358608994.4396194.359500594.4
 Yes7535.7346905.62405.7352265.6
Major road <50mNo1211291.957581892.8387892.358449392.7
Yes10588.1449617.23237.7457387.3
Major road <50m or Highway <150mNo1147287.154656388.0367987.655478388.0
Yes169812.97421612.052212.47544812.0
Air pollution MinimumMediumMaximumInterquartileMinimumMediumMaximumInterquartileMinimumMediumMaximumInterquartileMinimumMediumMaximumInterquartile
PM2.5 (μg/m³)0.004.110.31.50.004.010.61.60.14.110.41.70.04.010.61.6
Black carbon (μg/m³)0.001.15.021.20.000.85.61.00.01.15.01.30.01.05.61.0
NO2 (ppb)12.031.161.49.210.929.966.69.012.031.357.79.210.929.966.69.0
NO (ppb)6.829.5119.312.16.628.4176.613.68.229.7101.013.76.628.4176.613.6
Noise (Lden dB(A)) 33.060.886.56.04.460.792.45.535.460.879.75.64.460.792.45.5
Greenness (NDVI) -0.10.20.60.1-0.10.30.60.1-0.00.30.60.1-0.10.30.60.1
  1. aComorbidities include traumatic brain injury, diabetes, hypertension, stroke, coronary heart disease, congestive heart failure and arrhythmia