Table 2.
Logistic regression analysis of odds of delay (BSID-III score<85), for cognitive, motor and expressive language domains by maternal HIV viremia in pregnancy
| Variable | Cognitive delay10, 11 | Motor delay10, 11 | Expressive language* delay10, 11 | |||
|---|---|---|---|---|---|---|
| OR (95% CI) | aOR (95% CI) | OR (95% CI) | aOR (95% CI) | OR (95% CI) | aOR (95% CI) | |
| Maternal variables | ||||||
| Log10 viral copies x year/mL (VCY) | 1.24 (0.67; 2.30) | 1.68 (0.84; 3.34) | 1.72 (0.89; 3.32) | 3.32 (1.36; 8.14) | 2.42 (1.45; 4.04) | 2.79 (1.57; 4.94) |
| Log10 HIV viral load, ART initiation | 1.41 (0.79; 2.51) | - | 1.83 (0.96; 3.49) | - | 2.65 (1.58; 4.45) | - |
| HIV VL ≥50 copies/mL vs. <50, delivery | 1.00 (0.34; 2.90) | - | 2.56 (0.95; 6.88) | - | 2.05 (0.97; 4.33) | - |
| HIV VL ≥1000 copies/mL vs. <1000, delivery | 2.02 (0.41; 9.95) | - | 4.00 (0.98; 16.36) | - | 2.47 (0.70; 8.67) | - |
| Nadir CD4 cell count (cells/mm3) | 0.999 (0.996; 1.001) | - | 0.999 (0.997; 1.002) | - | 0.996 (0.994; 0.999) | - |
| <200 | Ref | - | Ref | - | Ref | - |
| 200 – 349 | 1.49 (0.37; 6.01) | - | 0.92 (0.25; 3.38) | - | 0.71 (0.29; 1.76) | - |
| 350 – 499 | 1.65 (0.38; 7.11) | - | 0.37 (0.06; 2.14) | - | 0.34 (0.11; 1.04) | - |
| ≥ 500 | 0.63 (0.12; 3.33) | - | 0.79 (0.20; 3.17) | - | 0.17 (0.05; 0.59) | - |
| Current/prior tuberculosis vs. none | 2.42 (0.80; 7.29) | - | 3.95 (1.34; 11.64) | - | 2.53 (1.04; 6.14) | - |
| Hemoglobin (g/dL) | 0.68 (0.46; 0.99) | - | 0.60 (0.39; 0.91) | - | 0.82 (0.61; 1.10) | - |
| Anemic (<11 g/dL vs ≥11 g/dL) | 1.64 (0.64; 4.19) | - | 2.00 (0.71; 5.64) | - | 1.15 (0.56; 2.34) | - |
| Maternal age (years) | 1.06 (0.98; 1.14) | - | 1.02 (0.93; 1.11) | - | 0.99 (0.93; 1.05) | - |
| Age ≥ 30 years (vs. <30) | 1.61 (0.64; 4.05) | 0.89 (0.71; 5.03) | 1.02 (0.39; 2.70) | 1.26 (0.38; 4.19) | 0.89 (0.44; 1.81) | 1.08 (0.50; 2.32) |
| Poverty score 1 | 0.85 (0.55; 1.29) | 0.84 (0.52; 1.34) | 0.98 (0.63; 1.53) | 0.82 (0.47; 1.43) | 1.07 (0.77; 1.48) | 1.26 (0.88; 1.80) |
| Education 2 | 0.44 (0.12; 1.56) | 0.37 (0.10; 1.48) | 1.01 (0.34; 2.98) | 0.70 (0.17; 2.96) | 0.43 (0.17; 1.10) | 0.26 (0.09; 0.76) |
| Depression 3 | 2.92 (0.86; 9.84) | - | 2.14 (0.56; 8.17) | - | 2.32 (0.82; 6.56) | - |
| Intimate partner violence 4 | 0.99 (0.32; 3.14) | 1.34 (0.33; 3.92) | 3.58 (1.31; 9.73) | 4.72 (1.36; 16.32) | 0.86 (0.35; 2.11) | 0.62 (0.23; 1.66) |
| Risky drinking 5 | 0.58 (0.19; 1.82) | 0.51 (0.15; 1.74) | 1.30 (0.46; 3.64) | 0.58 (0.16; 2.17) | 1.58 (0.75; 3.30) | 1.65 (0.72; 3.76) |
| Infant characteristics | ||||||
| Gestation at delivery (weeks) 6 | 0.82 (0.70; 0.96) | 0.77 (0.64; 0.92) | 0.65 (0.53; 0.78) | 0.54 (0.42; 0.70) | 1.14 (0.95; 1.38) | 1.11 (0.90; 1.37) |
| Preterm (<37 weeks) vs. term | 2.58 (0.85; 7.78) | - | 8.09 (2.82; 23.24) | - | 0.54 (0.15; 1.90) | - |
| Infant sex: male vs. female | 0.88 (0.35;2.22) | - | 1.16 (0.44; 3.07) | - | 0.97 (0.48; 1.96) | - |
| Small-for-gestational age 7 | 1.13 (0.31; 4.11) | - | 2.06 (0.62; 6.80) | - | 1.97 (0.80; 4.86) | - |
| Duration of any breastfeeding (months) 8 | 1.03 (0.95; 1.11) | - | 0.99 (0.91;1.07) | - | 0.98 (0.92; 1.04) | - |
| Duration of exclusive breastfeeding (weeks) 9 | 1.02 (0.97; 1.06) | - | 1.00 (0.96; 1.05) | - | 1.00 (0.97; 1.03) | - |
Language score based on expressive language subscale only; Abbreviations – BSID-III, Bayley Scales of Infant and Toddler Development Third Edition; ART, antiretroviral therapy; OR, odds ratio; aOR, adjusted odds ratio; CI, confidence interval; Except where otherwise indicated, maternal variables represent measures taken at first antenatal clinic booking, prior to ART initiation
Calculated using standardized asset score (access to flush toilet, running water, electricity in home, refrigerator, telephone, television, formal housing) and maternal employment; higher score indicates less relative disadvantage
Education: comparing women who completed secondary schooling vs. those who did not
Depression: EPDS (Edinburgh postnatal depression scale) score of ≥ 13, compared to score <13
Any physical, sexual or psychological violence as measured with World Health Organization violence against women questionnaire (compared to no IPV)
Risky drinking, defined as Alcohol use disorders identification test (AUDIT-C) score ≥3 (compared to scores <3)
Gestation at delivery: based on early ultrasound and/or last menstrual period as indicated
SGA, birthweight below 10th centile for gestational age (Intergrowth-21st reference standards); compared to appropriate for gestational age
Breastfeeding durations determined by maternal self-report: last study visit at which breastfeeding reported taken as last day of breastfeeding
Exclusivity defined as receiving only breastmilk and medication; non-time-varying; duration of exclusive breastfeeding among those who never exclusively fed set as zero
Interaction terms: VCY-gestational age for cognitive, p=0.84; motor, p=0.46; expressive language, p=0.40; VCY-sex: cognitive, p=0.13; motor, p=0.30; expressive language, p=0.16; VCY-breastfeeding duration: cognitive, p=0.10; motor, p=0.74; expressive language, p=0.62
Sensitivity analysis results:
Adjusting for maternal age, education, intimate partner violence, risky drinking and poverty score (not including gestational age): cognitive aOR 1.39 (95% CI 0.73; 2.63); motor aOR 1.70 (95% CI 0.87; 3.33); expressive language aOR 2.89 (95% CI 1.63; 5.11).
Adjusting for maternal age, education, intimate partner violence, risky drinking and poverty score; maternal history of tuberculosis and CD4 cell count (not including gestational age): cognitive aOR 1.21 (95% CI 0.57; 2.58); motor aOR 1.76 (95% CI 0.80; 3.90); expressive language aOR 2.04 (95% CI 1.05; 3.94).
Adjusting for maternal age, education, intimate partner violence, risky drinking and poverty score; maternal history of tuberculosis, CD4 cell count AND gestational age: cognitive aOR 1.55 (95% CI 0.70; 3.42); motor aOR 3.72 (95% CI 1.35; 10.26); expressive language aOR 1.89 (95% CI 0.96; 3.71).