Table 4.
Summary of risk factors for infant mortality by underlying disease.
| Risk factor | Included study | Risk estimate+(95%CI) | Risk factor definitions |
|---|---|---|---|
| DIARRHEA (n = 4 STUDIES) | |||
| Dehydration | Sachdev et al. (49) | 1.96 (0.5–8.2) | Severe dehydration |
| Islam et al. (62)* | NSS, estimate NR | Severe dehydration | |
| Maternal education | Islam et al. (62)* | 2.12 (1.37–3.28) | < 1 year of schooling |
| Teka et al. (58) | 1.96 (0.5–0.82) | No education | |
| Non-breastfed | Santhanakrishnan et al. (51) | 2.29, estimate NR | Not exclusively breastfed |
| Teka et al. (58) | 4.19 (1.3–13.2) | Non-breastfed | |
| Islam et al. (62)* | 2.35 (1.44–3.84) | Non-breastfed | |
| Poor nutritional status | Sachdev et al. (49) | 3.3 (2.7–4) | Weight for age < 50% |
| Sachdev et al. (49) | 1.9 (1.6–23) | Height for age < 85% | |
| Santhanakrishnan et al. (51) | 4.94, estimate NR | Degree of malnutrition of 2 or 3 on Gomez scale | |
| Teka et al. (58) | 84.16 (9.1–775.9) | Weight for height < 70% | |
| Islam et al. (62)* | 2.97 (1.43–6.16) | Height for age < 85% | |
| Young age | Islam et al. (62)* | 4.57 (2.9–7.18) | Age < 6 months |
| Santhanakrishnan et al. (51) | NSS, estimate NR | Age < 6 months | |
| Sachdev et al. (49) | NSS, estimate NR | Age < 6 months | |
| ACUTE RESPIRATORY INFECTION OR PNEUMONIA (n = 13 STUDIES) | |||
| Alteration of status | Demers et al. (24) | 3.23 (1.17–8.94) | Moderate/severe mental alteration |
| Sehgal et al. (53) | NSS, estimate NR | NR | |
| Sehgal et al. (53) | NSS, estimate NR | NR | |
| Zhang et al. (61) | NSS, estimate NR | NR | |
| Cyanosis | Zhang et al. (61) | NSS, estimate NR | Central cyanosis |
| Duke et al. (27) | 1.46 (0.79–3.45) | NR | |
| Sehgal et al. (53) | NSS, estimate NR | NR | |
| Nantada et al. (42) | NSS, estimate NR | NR | |
| Low oxygen saturation | Djelantik et al. (26) | 2.7 (2.1–3.5) | SpO2 < 85% |
| Duke et al. (27) | 2.46 (1.3–4.65) | SpO2 < 70% | |
| Nantanda et al. (42) | SS > 1, estimate NR | NR | |
| Smyth et al. (57) | SS > 1, estimate NR | NR | |
| Ramakishna et al. (47) | 2.96 (0.94–0.29) | SpO2 < 90% | |
| Zhang et al. (61) | NSS, estimate NR | SpO2 < 90% | |
| Low respiratory rate | Djelantik et al. (26) | 4.6 (2.5–8.5) | < 40 breaths per minute |
| Shann et al. (54) | NSS, estimate NR | < 40 breaths per minute | |
| Malnutrition | Djelantik et al. (26) | 1.1(0.93–1.3) | Weight for age < 5th percentile |
| Demers et al. (24) | 2.74 (0.96–7.76) | Weight for height >2SD less than median for age | |
| Nantanda et al. (42) | SS > 1, estimate NR | NR | |
| Nathoo et al. (43) | 3.8 (2.7–5.4) | Weight for age < 60% | |
| Sehgal et al. (53)* | 3.9 (1.01–9.07) | WAZ < −3 | |
| Tupasi et al. (59) | 4.4 (2–9.52) | First degree malnutrition on Gomez Scale | |
| Duke et al. (27) | 6.32 (2.74–14.57) | Weight for age < 60% | |
| Smyth et al. (57) | SS > 1, estimate NR | Low WAZ& | |
| Shann et al. (54) | NSS, estimate NR | Weight for age < 80% | |
| Young age | Djelantik et al. (26) | 3.6 (2.8–4.6) | Age < 4 months |
| Nathoo et al. (43) | 2.4 (1.6–3.5) | Age < 6 months | |
| Rodriguez et al. (48) | 1.11(0.51–2.41) | Age < 6 months | |
| Smyth et al. (57) | NSS, estimate NR | Age < 6 months | |
| SERIOUS INFECTION OR SEPSIS (n = 3 STUDIES) | |||
| Bacteremia | Mulholland et al. (41) | SS > 1, estimate NR | NR |
| Need for >2 inotropes | Khan et al. (34) | 3.5 (1.3–9.2) | >2 inotropes |
| Organ dysfunction | Khan et al. (34) | 18 (2.2–144) | >2 dysfunctional organs |
| PRISM score >10 | Bhatnagar et al. (19)Intervention | 0.57 (0.27–1.23) | 10 mg zinc intake daily |
| Zinc intake | Khan et al. (34) | 1.5 (0.6–4) | >10 |
Denotes that post-discharge populations were assessed.
Bolded risk factors are statistically significant.
Denotes all risk estimates are odds ratios, unless relative risk ratio denoted by RR.
Denotes low weight-for-age Z score.
NR denotes “Not Reported.”
NA denotes “Not Applicable.”
SS>1, statistically significant association with risk estimate >1.
SS < 1, statistically significant association with risk estimate < 1.
Intervention: In this study, the intervention was zinc intake and the comparator was normal care. The exposure (suspected bacterial infection) was the same for both groups. In all other studies included in this systematic review, the intervention is usual care with exposure to the risk factor, and the comparator is intervention without exposure to risk factor.