DNA methylation as a potential mediator of the association between indoor air pollution and neurodevelopmental delay in a South African birth cohort

Table 1 Study characteristics of the DCHS participants

Characteristic	Participants (N = 142)*
Ancestry
Black	69 (48.6%)
Mixed	73 (51.4%)
Sex
Female	57 (40.1%)
Alcohol use
Exposure	28 (19.7%)
Smoking^a
Non-smoker	38 (26.8%)
Passive smoker	57 (40.1%)
Active smoker	47 (33.1%)
Maternal HIV status
HIV +	30 (21.1%)
Birth weight (grams)	3120 (512)
Maternal age (years)	27.20 (5.98)
SES score^b	0.092 (2.25)
Bayley score—cognitive composite	85.14 (8.65)
Bayley’s score—language composite	84.31 (12.22)
Bayley’s score—motor composite	94.04 (13.74)
Bayley’s score—general adaptive composite	83.72 (13.29)
PM10 concentration (µg/m³)	64.6 (96.8)

*The number of participants includes those with data available for all covariates and a composite Bayley’s score in at least one of the relevant domains (Cognitive, General Adaptive, Language, and Motor)
^aSmoking status was determined by urine cotinine levels (ng/ml), defined as follows: < 10 ng/ml non-smoker, 10–49 ng/ml passive smoker, > = 500 ng/ml active smoker
^bSES score description can be found in the supplement section

ISSN: 1868-7083