Table 1. Associations between antibiotic use in the first two years of life and characteristics of children and their families among 1741 children who remained in the MAL-ED cohort for at least two years, 2009–2014.
| Characteristic | All children | Children with high antibiotic usea | Difference in proportion of days on antibioticsb (95% CI) | RR for high antibiotic usea,b (95% CI) |
|---|---|---|---|---|
| Child’s sex, no. of children | ||||
| Female | 853 | 436 (51.1) | 0.00 (ref) | 1.00 (ref) |
| Male | 888 | 543 (61.2) | 0.01 (0.00 to 0.01) | 1.13 (0.99 to 1.28) |
| Socioeconomic status (per 0.5 increase in WAMI score),c mean (SD) | 0.57 (0.22) | 0.57 (0.22) | 0.02 (0.01 to 0.03) | 1.10 (0.86 to 1.40) |
| Household monthly income,c no. of children | ||||
| Below site-specific median | 1093 | 615 (56.3) | 0.00 (ref) | 1.00 (ref) |
| At or above site-specific median | 647 | 364 (56.3) | 0.01 (0.00 to 0.01) | 1.02 (0.90 to 1.17) |
| Mother’s age (per 5 year increase),c mean (SD) | 26 (5.9) | 26 (6.0) | 0.00 (0.00 to 0.00) | 0.99 (0.94 to 1.05) |
| Mother’s education,c no. of children | ||||
| < 6 years | 637 | 347 (54.5) | 0.00 (ref) | 1.00 (ref) |
| ≥ 6 years | 1102 | 630 (57.2) | 0.00 (0.00 to 0.01) | 1.02 (0.88 to 1.19) |
| Crowding (per 1 person increase in mean people per household room),c mean (SD) | 2.4 (1.5) | 2.4 (1.5) | 0.00 (0.00 to 0.00) | 0.98 (0.93 to 1.04) |
| Birth weight,c no. of children | ||||
| Normal | 1275 | 711 (55.8) | 0.00 (ref) | 1.00 (ref) |
| Low | 295 | 166 (56.3) | 0.00 (0.00 to 0.01) | 1.05 (0.86 to 1.29) |
| Age at first milk or solids introduced (per 1 month increase),c mean (SD) | 2.7 (2.0) | 2.7 (2.0) | 0.00 (0.00 to 0.00) | 1.00 (0.97 to 1.04) |
| Age at stopping all breastfeeding (per 1 month increase),c mean (SD) | 21.0 (7.6) | 20.9 (7.7) | 0.00 (0.00 to 0.00) | 1.00 (0.99 to 1.01) |
| Sanitation,c no. of children | ||||
| Unimproved | 496 | 281 (56.7) | 0.00 (ref) | 1.00 (ref) |
| Improved | 1243 | 697 (56.1) | 0.01 (0.00 to 0.02) | 1.09 (0.86 to 1.38) |
| Water source,c no. of children | ||||
| Unimproved | 171 | 100 (58.5) | 0.00 (ref) | 1.00 (ref) |
| Improved | 1568 | 878 (56.0) | 0.00 (−0.01 to 0.01) | 0.94 (0.68 to 1.28) |
CI: confidence interval; MAL-ED: Etiology, Risk Factors, and Interactions of Enteric Infections and Malnutrition and the Consequences for Child Health and Development Project; ref: reference; RR: risk ratio; SD: standard deviation; WAMI: water and sanitation, assets, maternal education and income.
a High antibiotic use was defined as receiving at or above the site-specific median number of antibiotic courses in the first two years of life.
b In the first two years of life among children followed for at least two years. All estimates were adjusted for site; proportion of days ill with diarrhoea, cough, fever, vomiting or fieldworker-confirmed acute lower respiratory tract illness in the first 2 years of life; and the interaction between the proportion of days ill and study site.
c Data on income, mother’s age and education, crowding, sanitation and water source missing for 2 children; income missing for 1 child; birth weight missing for 171 children; age at first milk or solids missing for 17 children; age at stopping all breastfeeding missing for 8 children.