Table 3.
Multivariable regression analysis of factors associated with inpatient and post-discharge mortality
Inpatient analysis | Post-discharge analysis | |||
Adjusted SHR* | P value | Adjusted HR | P value | |
Demographics | ||||
Age in days | ||||
0–2 | 2.12 (1.46–3.06) | <0.001 | 1.30 (0.73–2.31) | 0.37 |
3–7 | 3.88 (2.46–6.10) | <0.001 | 0.80 (0.38–1.68) | 0.56 |
8–28 | 1.42 (0.90–2.25) | 0.13 | 1.45 (0.81–2.59) | 0.21 |
>28 | Reference | Reference | ||
Sex (female) | 0.91 (0.78–1.07) | 0.26 | 0.98 (0.74–1.31) | 0.94 |
Born at KCH | ||||
Yes | † | Reference | ||
No | † | 1.59 (1.18–2.14) | 0.003 | |
Admission days (log) | † | 1.87 (1.54–2.26) | <0.001 | |
Type of discharge | ||||
Normal | † | Reference | ||
Absconded | † | 3.01 (1.22–7.46) | 0.02 | |
Transferred/referred | † | 12.8 (8.11–20.2) | <0.001 | |
Anthropometry | ||||
Weight (kg) | ||||
<1.5 | 2.16 (1.75–2.67) | <0.001 | 1.95 (1.38–2.74) | <0.001 |
1.5 to <2.5 | 1.42 (1.16–1.74) | 0.001 | 0.82 (0.48–1.42) | 0.49 |
≥2.5 | Reference | Reference | ||
Missing weight | 3.85 (2.59–5.71) | <0.001 | – | |
Clinical features | ||||
Axillary temperature | ||||
<36°C | 1.44 (1.17–1.78) | 0.001 | 1.06 (0.74–1.53) | 0.75 |
36–37.5°C | Reference | Reference | ||
>37.5°C | 1.09 (0.84–1.41) | 0.53 | 0.69 (0.47–0.99) | 0.04 |
Missing temperature | 1.03 (0.38–2.75) | 0.96 | 1.09 (0.15–8.22) | 0.93 |
Respiratory rate/min | ||||
Bradypnoea | 1.45 (1.09–1.93) | 0.01 | 1.66 (0.76–3.63) | 0.21 |
Normal | Reference | Reference | ||
Tachypnoea | 0.80 (0.67–0.95) | 0.01 | 1.24 (0.93–1.66) | 0.14 |
Missing | 1.51 (0.64–3.56) | 0.34 | 0.80 (0.11–5.82) | 0.82 |
Heart rate/min | ||||
Bradycardia | 1.40 (1.08–1.82) | 0.01 | † | |
Normal | Reference | |||
Tachycardia | 1.14 (0.94–1.37) | 0.18 | † | |
Missing | 0.41 (0.03–5.13) | 0.49 | † | |
Hypoxia (SaO2 <90%) | 1.62 (1.37–1.92) | <0.001 | † | |
Capillary refill >2 s | 1.34 (0.97–1.86) | 0.08 | † | |
Lower chest wall indrawing | 1.41 (1.14–1.75) | 0.002 | † | |
Stridor | 1.93 (0.92–4.03) | 0.08 | † | |
Breathing difficulty | 1.45 (1.15–1.82) | 0.001 | † | |
Weak pulse | 1.61 (1.19–2.17) | 0.002 | 2.22 (1.01–4.89) | 0.04 |
Bulging fontanel | 2.45 (0.91–6.65) | 0.08 | 2.59 (0.92–7.26) | 0.07 |
Impaired consciousness | 2.21 (1.72–2.84) | <0.001 | † | |
Pallor | 1.30 (0.98–1.71) | 0.07 | † | |
Laboratory features | ||||
Meningitis | 5.45 (2.50–11.8) | <0.001 | 2.16 (0.73–6.37) | 0.17 |
HIV antibody positive | 1.15 (0.81–1.63) | 0.43 | 0.94 (0.43–2.05) | 0.87 |
Bacteraemia | 2.21 (1.51–3.22) | <0.001 | † | |
White blood cells (10⁹ cells/L) | ||||
<4 | 2.17 (1.30–3.62) | 0.003 | † | |
4–20 | Reference | † | ||
>20 | 1.71 (1.43–2.04) | <0.001 | † | |
Unavailable | 1.09 (0.82–1.44) | 0.57 | † | |
Model performance | ||||
Bootstrapped AUC (95% CI) | 0.88 (0.86 to 0.89) | 0.76 (0.73 to 0.80) |
*The SHR are from the Fine and Gray’s proportional subhazards model, HR from the shared frailty Cox regression model.
†Variables not selected for inclusion in the multivariable model, AUC; area under receiver operating characteristics. Meningitis: positive CSF culture, or positive CSF microscopy, or positive CSF antigen test, or elevated CSF WBC count (≥0.02x10⁹/L in young infants aged 0–28 days OR, ≥0.01 x 10⁹/L in young infants aged 29–59 days) PLUS a positive blood culture for a known pathogen.
CSF, cerebrospinal fluid; KCH, Kilifi County Hospital; SHR, subdistribution HR; WBC, white blood cell.