. 2023 Dec 1;131(12):127003. doi: 10.1289/EHP12141

Table 1.

Characteristics of the study populations $65 plus$ years of age in Medicare, CanCHEC, and ELAPSE cohorts.

	Medicare	Stacked CanCHEC	ELAPSE
	Medicare	Stacked CanCHEC	Belgian	Danish	Dutch	Norwegian	Roman	Swiss
Year of enrollment	2000–2016	1991, 1996, 2001	2001	2000	2008	2001	2001	2001
Follow-up
Start-end	2000–2016	1991–2016	2001–2011	2000–2015	2008–2012	2001–2016	2001–2015	2001–2014
Persons at risk
$n$	74,493,754	942,600^a	1,291,067	697,359	2,314,101	551,962	359,715	945,846
Person-years at risk
$n$	636,817,430	9,106,200^a	10,299,384	6,835,701	10,351,266	5,674,821	3,571,859	9,499,911
All-cause mortality
$Rate times 1,000$ person-years	40.5	51.9	54.5	72.3	46.4	68.0	53.3	54.5
Natural mortality^b
$Rate times 1,000$ person-years	—	50.3	52.1	70.0	45.1	65.0	51.0	52.4
Sex (%)
Males	44.6	42.9	45.8	41.9	43.4	41.2	41.6	42.0
Females	55.4	57.1	54.2	58.1	56.6	58.8	58.4	58.0
Baseline age (years)
$Mean \pm SD$	$69.2 \pm 6.7$	$70.6 \pm 4.6$	$74.5 \pm 6.7$	$75.2 \pm 7.1$	$74.5 \pm 7.1$	$75.9 \pm 7.0$	$74.6 \pm 6.9$	$74.8 \pm 6.9$
$particulate matter begin subscript 2.5 end subscript$ exposure during follow-up ( ${μ g / m}^{3}$ )
$Mean \pm SD$	$9.8 \pm 3.2$	$8.2 \pm 2.6$	$15.4 \pm 1.5$	$9.9 \pm 1.4$	$15.7 \pm 1.4$	$7.0 \pm 1.6$	$17.8 \pm 1.1$	$16.1 \pm 3.1$
5th−95th percentile	5.0–14.5	3.7–12.0	12.3–19.3	6.5–13.1	12.3–18.1	4.2–10.3	14.8–22.4	10.3–21.7
Individual-level SES and ethnicity
Country of origin/ immigration status
Local/nonimmigrant	—	74.0	99.2	96.7	87.9	—	—	—
Foreign/immigrant	—	26.0	0.8	3.3	12.1	—	—	—
Nationality (%)
Swiss	—	—	—	—	—	—	—	93.1
Non-Swiss	—	—	—	—	—	—	—	6.9
Mother tongue (%)
German and Rhaeto-Romansch	—	—	—	—	—	—	—	69.9
French	—	—	—	—	—	—	—	20.8
Italian	—	—	—	—	—	—	—	7.3
Other	—	—	—	—	—	—	—	2.1
Race (%)
White	84.1	—	—	—	—	—	—	—
Black	8.9	—	—	—	—	—	—	—
Asian	1.8	—	—	—	—	—	—	—
Hispanic	2.0	—	—	—	—	—	—	—
North American Native	0.3	—	—	—	—	—	—	—
Visible minority status (%)
Yes	—	4.9	—	—	—	—	—	—
No	—	95.1	—	—	—	—	—	—
Indigenous identity (%)
Yes	—	1.1	—	—	—	—	—	—
No	—	98.9	—	—	—	—	—	—
Medicaid eligibility (%)
Eligible	11.6	—	—	—	—	—	—	—
Ineligible	88.4	—	—	—	—	—	—	—
(Household) income in local currency
Levels	—	Quintiles	—	Deciles	Deciles	Quartiles	—	—
Educational level (%)
Primary or below	—	55.2	50.7	—	—	48.9	51.0	41.5
Secondary	—	37.2	38.8	—	—	40.4	37.9^c	45.5
Tertiary	—	7.5	10.5	—	—	10.7	11.1	13.0
Marital status (%)
Single	—	5.2	6.1	—	5.4	7.4	7.0	7.3
Married	—	66.7	57.9	—	58.5	52.3	57.4	58.7
Divorced/separated	—	6.0	4.6	—	7.3	6.3	3.4	6.0
Widowed	—	21.7	31.4	—	28.7	34.0	32.2	28.0
Employment status (%)
Employed	—	11.1	0.6	4.5	—	6.1	3.7	5.4
Unemployed	—	0.5	0	0.1	—	0.1	0.1	0.1
Homemaker	—	—	2.0	—	—	—	30.1	0
Retired	—	88.3^d	97.4	95.4^e	—	93.8	58.2	94.5

Note: —, no data; CanCHEC, Canadian Census Health and Environment Cohorts; ELAPSE, Effects of Low-Level Air Pollution: A Study in Europe; $particulate matter begin subscript 2.5 end subscript$ , particulate matter with aerodynamic diameter $less than or equal to 2.5 micrometers$ ; SD, standard deviation.

^{^a}

Rounded to nearest 100 for confidentiality.

^{^b}

Natural mortality was defined by the International Classification of Diseases, 9th revision (ICD-9) or 10th revision (ICD-10) codes: ICD-9: 1–779; ICD-10: A00–R99.

^{^c}

Grouped junior high school and high school.

^{^d}

Employment status has three classes in CanCHEC: employed, unemployed, and not in the labor force (i.e., persons who left on disability, had retired, or had never worked).

^{^e}

Employment status has three classes in the Danish cohort: employed, unemployed, and pensioner (i.e., retired, sick, cash support, student, pension, or others).