Skip to main content

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

Level

Covariates

 

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)

Individual

Age

Minimum

45

45

45

45

Median

76

57

72

58

Maximum

83

83

83

83

Interquartile

9

18

12

18

 

Count

%

Count

%

Count

%

Count

%

Sex

Female

7785

59.1

325967

52.5

1941

46.2

332255

52.7

Male

5385

40.9

294812

47.5

2260

53.8

297976

47.3

Comorbiditya

No

6684

50.7

454399

73.2

2319

55.2

458996

72.8

Yes

6486

49.3

166380

26.8

1882

44.8

171235

27.2

Neighborhood

Household income

Lowest

3426

26.0

113002

18.2

968

23.0

115566

18.4

Low

2713

20.6

113505

18.3

857

20.4

115441

18.3

Middle

2307

17.5

122122

19.7

772

18.4

123781

19.6

Upper middle

2323

17.6

130843

20.1

745

17.7

132509

21.0

Upper

2401

18.3

141307

23.7

859

20.5

142934

22.7

Education

Less than secondary

1851

14.0

80501

12.9

574

13.7

81883

13.0

Secondary

3575

27.2

168156

27.1

1108

26.4

170756

27.1

Post-secondary

7744

58.8

372122

60.0

2519

59.9

377592

59.9

Chinese

<10% of population in Neighborhood

6325

48.0

295442

47.6

2024

48.2

300035

47.6

> 10% of population in Neighborhood

6845

52.0

325337

52.4

2177

51.8

330196

52.4

South Asian

<10% of population in Neighborhood

6538

49.7

294834

47.5

2019

48.1

299608

47.5

> 10% of population in Neighborhood

6632

50.3

325945

52.5

2182

51.9

330623

52.5

Visible minority

<10% of population in Neighborhood

10293

78.2

487142

78.5

3305

78.7

494477

78.5

> 10% of population in Neighborhood

2877

21.8

133637

21.5

896

21.3

135754

21.5

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 <50m

No

12896

97.9

607594

97.9

4104

97.7

279741

97.9

 

Yes

274

2.1

13185

2.1

97

2.3

13375

2.1

Highway <150m

No

12417

94.3

586089

94.4

3961

94.3

595005

94.4

 

Yes

753

5.7

34690

5.6

240

5.7

35226

5.6

Major road <50m

No

12112

91.9

575818

92.8

3878

92.3

584493

92.7

Yes

1058

8.1

44961

7.2

323

7.7

45738

7.3

Major road <50m or Highway <150m

No

11472

87.1

546563

88.0

3679

87.6

554783

88.0

Yes

1698

12.9

74216

12.0

522

12.4

75448

12.0

Air pollution

 

Minimum

Medium

Maximum

Interquartile

Minimum

Medium

Maximum

Interquartile

Minimum

Medium

Maximum

Interquartile

Minimum

Medium

Maximum

Interquartile

PM2.5 (μg/m³)

0.00

4.1

10.3

1.5

0.00

4.0

10.6

1.6

0.1

4.1

10.4

1.7

0.0

4.0

10.6

1.6

Black carbon (μg/m³)

0.00

1.1

5.02

1.2

0.00

0.8

5.6

1.0

0.0

1.1

5.0

1.3

0.0

1.0

5.6

1.0

NO2 (ppb)

12.0

31.1

61.4

9.2

10.9

29.9

66.6

9.0

12.0

31.3

57.7

9.2

10.9

29.9

66.6

9.0

NO (ppb)

6.8

29.5

119.3

12.1

6.6

28.4

176.6

13.6

8.2

29.7

101.0

13.7

6.6

28.4

176.6

13.6

Noise (Lden dB(A))

 

33.0

60.8

86.5

6.0

4.4

60.7

92.4

5.5

35.4

60.8

79.7

5.6

4.4

60.7

92.4

5.5

Greenness (NDVI)

 

-0.1

0.2

0.6

0.1

-0.1

0.3

0.6

0.1

-0.0

0.3

0.6

0.1

-0.1

0.3

0.6

0.1

  1. aComorbidities include traumatic brain injury, diabetes, hypertension, stroke, coronary heart disease, congestive heart failure and arrhythmia