Non-linear association between admission temperature and neonatal mortality in a low-resource setting

Both neonatal hypothermia and hyperthermia represent important risk factors for neonatal
mortality, but information on mortality risk across a full range of neonatal temperatures is lacking
in low‑resource settings. We evaluated the association between neonatal mortality and a full range
of admission temperatures in a low‑resource setting. This retrospective observational study was
conducted at Beira Central Hospital, Mozambique. The relationship between admission temperature
and mortality was evaluated using multivariable analyses with temperature modeled as non‑linear
term. Among 2098 neonates admitted to the Special Care Unit between January–December 2017,
admission temperature was available in 1344 neonates (64%) who were included in the analysis.
A non‑linear association between mortality rate and temperature was identified. Mortality rate
decreased from 84% at 32 °C to 64% at 34.6 °C (− 8% per °C), to 41% at 36 °C (− 16% per °C), to 26% to
36.6 °C (− 25% per °C) and to 22% at 38.3 °C (− 2% per °C), then increased to 40% at 41 °C (+ 7% per °C).
Mortality rate was estimated to be at minimum at admission temperature of 37.5 °C. In conclusions,
the non‑linear relationship highlighted different mortality risks across a full range of neonatal
temperatures in a low‑resource setting. Admission temperature was not recorded in one third of
neonates