Skip to main content
. Author manuscript; available in PMC: 2019 Jan 1.
Published in final edited form as: Epidemiology. 2018 Jan;29(1):22–30. doi: 10.1097/EDE.0000000000000754

Table 1.

KAPPA cohort characteristics

Children with first year of life exposure data Children with prenatal exposure data
Characteristic n (%) Median first year of life n (%) Median prenatal
PM2.5 (μg/m3) NOX (ppb) CO (ppm) PM2.5 (μg/m3) NOX (ppb) CO (ppm)
Cohort 23,100 1.41 55.5 0.59 19,951 1.49 59.4 0.62
Sex
 Female 11,330 (49) 1.42 55.6 0.59 9,748 (49) 1.49 59.4 0.62
 Male 11,770 (51) 1.41 55.5 0.59 10,203 (51) 1.49 59.5 0.62
Race/Ethnicity
 Black 7,995 (35) 1.32 50.8 0.54 7,220 (36) 1.40 54.6 0.57
 White 9,034 (39) 1.37 54.3 0.57 8,467 (42) 1.45 58.0 0.60
 Other a 2,771 (12) 1.69 65.6 0.70 2,643 (13) 1.78 69.6 0.73
 Unknown race 3,300 (14) 1.54 61.6 0.63 1,621 (8) 1.70 69.7 0.69
 Hispanic ethnicity 1,839 (8) 1.42 54.2 0.60 1,759 (9) 1.51 58.7 0.63
Maternal education
 <12th grade 285 (1) 1.50 59.9 0.63 280 (1) 1.60 65.3 0.68
 High school/GED 2,605 (11) 1.25 48.6 0.52 2,524 (13) 1.32 52.3 0.54
 Some college or more 13,442 (58) 1.42 55.9 0.59 13,113 (66) 1.51 60.4 0.62
 Missing 6,768 (29) 1.45 57.3 0.60 4,034 (20) 1.56 61.1 0.64
Maternal asthma
 Yes 2,488 (11) 1.39 54.4 0.58 2,419 (12) 1.46 57.9 0.60
 No 17,998 (78) 1.41 55.5 0.59 17,532 (88) 1.50 59.6 0.62
 Missing 2,614 (11) 1.44 57.3 0.60 0 – – –
Neighborhood Socioeconomic Status b
 Highest SES 14,401 (62) 1.28 49.9 0.53 12,626 (63) 1.36 53.6 0.56
 Urban/Suburban 2,293 (10) 2.38 93.2 0.96 1,925 (10) 2.53 100.4 1.01
 Rural, average to low SES 1,130 (5) 0.95 37.7 0.40 974 (5) 1.02 41.5 0.43
 Lowest SES 5,272 (23) 1.65 64.2 0.68 4,423 (22) 1.74 68.9 0.71
City Region
 Metro Atlanta c 2,425 (11) 2.24 87.0 0.91 2,030 (10) 2.35 92.0 0.95
 ≤16 km from metro Atlanta 9,894 (43) 1.57 62.0 0.64 8,449 (42) 1.67 66.5 0.68
 >16 km from metro Atlanta 10,781 (47) 1.14 45.0 0.49 9,472 (47) 1.22 48.8 0.51
Kaiser Permanente enrollment duration d
 Enrolled until age 2 17,960 (78) 1.41 55.5 0.59 15,631 (78) 1.49 59.6 0.62
 Enrolled until age 3 14,251 (62) 1.42 56.0 0.59 12,434 (62) 1.50 60.4 0.62
 Enrolled until age 4 10,999 (48) 1.44 57.5 0.60 9,620 (48) 1.54 62.3 0.63
 Enrolled until age 5 8,592 (37) 1.46 59.0 0.60 7,521 (38) 1.57 64.5 0.64
 Enrolled until age 6 6,629 (29) 1.49 61.4 0.62 5,806 (29) 1.59 66.7 0.65
Cumulative asthma incidence e
 Age 2 1,994 (11) 1.37 54.6 0.57 1,731 (11) 1.45 58.6 0.60
 Age 3 2,627 (18) 1.39 55.0 0.58 2,316 (19) 1.47 59.4 0.60
 Age 4 2,650 (24) 1.42 56.8 0.59 2,309 (24) 1.51 61.4 0.61
 Age 5 2,465 (29) 1.47 58.9 0.60 2,132 (28) 1.55 64.0 0.63
 Age 6 2,149 (32) 1.51 61.6 0.62 1,854 (32) 1.59 67.1 0.66

SES indicates socioeconomic status, GED general educational development.

a

Includes Asian, American Indian, Alaska Native, Native Hawaiian or other Pacific Islander, and children identifying with more than one racial group

b

Neighborhood socioeconomic status was classified at census block group spatial resolution using child residence at time of birth and described using demographic clusters created by Georgia Department of Public Health32

c

Metro Atlanta defined as inside the I-285 perimeter of Atlanta

d

Reduction in sample size across follow-up reflects the shorter follow-up time available for children born in later years of the study (e.g., a child born in 2010 could be at most 3 years old at the time KAPPA follow-up ended in September 2013) as well as health maintenance organization enrollment attrition over time.

e

Cumulative asthma incidence (at least one asthma diagnosis (ICD-9 493.XX) and one asthma-related medication dispensing after the first year of life) calculated among children enrolled until each follow-up age