TABLE 3.
Predictors and incidence of infectious-cause hospitalization comparing HIV-exposed uninfected to HIV-unexposed children between 7 days and 3 months of age: crude and adjusted incidence rate ratios from Poisson regression analysis
| Crude IRR (95% CI)1 | Adjusted IRR (95% CI)1 Model A2 | Adjusted IRR (95% CI)1 Model B3 | |
|---|---|---|---|
| HIV exposure (HEU vs HU) | 3·50 (1·68–7·30) | 3·49 (1·68–7·27) | 3·39 (1·64–7·02) |
| Maternal education4 | 0·51 (0·25–1·07) | - | - |
| Running water and flush toilet in home5 | 0·39 (0·18–0·88) | 0·40 (0·18–0·87) | 0·43 (0·19–0·94) |
| Poverty category6 | |||
| Most disadvantaged | 1·00 | - | - |
| Moderate disadvantage | 0·80 (0·41–1·56) | - | - |
| Least disadvantaged | 0·48 (0·21–1·11) | - | - |
| Cigarette smoking in home7 | 0·51 (0·24–1·06) | - | - |
| Biomass fuel or paraffin use in home8 | 1·22 (0·62–2·40) | - | - |
| Intimate partner violence, antenatal9 | 1·49 (0·71–3·11) | - | - |
| Risky drinking, antenatal10 | 0·80 (0·34–1·91) | - | - |
| Postpartum depression11 | 2·15 (0·66–6·95) | 2·53 (0·85–7·51) | 2·45 (0·82–7·30) |
| Preterm <37 weeks | 1·64 (0·73–3·69) | 0·79 (0·27–2·34) | - |
| Small-for-gestational age12 | 1·94 (0·90–4·18) | - | - |
| Male vs female | 0·81 (0·44–1·47) | - | - |
| Season of birth: warm vs cold months13 | 1·31 (0·71–2·43) | 1·16 (0·65–2·08) | 1·26 (0·70–2·27) |
| Early initiation of breastfeeding14 | 0·44 (0·20–1·00) | - | - |
| Ever exclusively breastfed (EBF)14 | 0·58 (0·28–1·21) | - | - |
| Optimal breastfeeding until 3 months14 | 0·42 (0·18–0·99) | 0·36 (0·14–0·92) | - |
| WAZ <−2 in previous age interval15 | 3·73 (1·73–8·03) | 2·87 (1·41–5·85) | - |
| Vaccination status, per age interval16 | |||
| Complete and timely | 1·00 | 1·00 | 1·00 |
| Delayed or incomplete | 5·47 (2·13–14·07) | 8·01 (2·18–29·43) | 9·25 (3·76–22·79) |
| Data not available | 0·68 (0·30–1·55) | 0·64 (0·27–1·49) | 0·66 (0·28–1·59) |
Abbreviations: IRR, incidence rate ratios; CI, confidence interval; HEU, HIV-exposed uninfected children; HU, HIV-unexposed children
Admission defined as 2 or more days; estimates from Poisson regression with robust variance estimates, clustered on mother-child pairs
Model A includes potential confounders and mediators of the HIV-exposure – hospitalization relationship (access to flush toilet and running water, maternal postpartum depression, preterm birth, breastfeeding, underweight, season of birth and vaccination status)
Model B only includes confounders (access to flush toilet and running water, postpartum depression, season of birth and vaccination status)
Completed vs did not complete secondary education
vs does not have both
Categories based on poverty “score” (combination of employment and a standardized asset score which includes running water and flush toilet)
Maternal report of own or other household members smoking, at 6 weeks’, 6 and/or 12 months’ study visits (vs never)
Maternal report of energy sources at 6 weeks’, 6 and/or 12 months’ study visits (vs. never)
Any physical, sexual or psychological violence as measured with World Health Organization violence against women questionnaire at first antenatal visit (vs none)
Risky drinking, defined as Alcohol use disorders identification test (AUDIT-C) score ≥3 vs <3, as reported at first antenatal visit
Edinburgh postnatal depression score ≥13 vs <13 at 6 weeks’ study visit
Birthweight for gestational age, percentile <10th, based on Intergrowth-21st growth reference standards (vs appropriate for gestational age)
Seasons defined as: Spring, 01 September to 30 November; Summer, 01 December to 28/29 February; Autumn, 01 March to 31 May; Winter, 01 June to 31 August
Based on 24 hour recall, maternal report; exclusive defined as only breastmilk with prescribed medicine; non-time-varying; early initiation defined as within 1 hour of birth; “optimal” defined for time period of 0–3 months, ie early initiation and exclusive breastfeeding for at least 3 months
Time-varying: weight-for-age Z-score < 2 (underweight) at any point during the preceding age interval
Time varying: based on Road to Health Booklet information; delayed vaccination defined as receipt >2 weeks after recommended age
Effect measure modification tests (interaction terms using adjusted model A): HEU status and infant sex, p=0·36; HEU status and optimal breastfeeding, p=0·80; HEU and vaccination status, p=0·17; HEU status and preterm birth, p=0·18; HEU status and SGA, p=0·52