Antipyretic Efficacy of Bromocriptine in Central Fever: an Exploratory Analysis.

Abstract

'Central' fevers are thought to result from disruption of hypothalamic thermoregulatory pathways following severe brain injuries. Bromocriptine, due to its central dopamine receptor agonism, has been hypothesized to have antipyretic effect in this setting. However, clinical evidence for this off-label use is limited to a few case reports. In this retrospective cohort study, we analyzed the effect of bromocriptine administration on body temperature in acute brain injury patients with suspected central fever. We screened a cohort of adult patients that received bromocriptine in the neurologic-intensive care unit of a tertiary care hospital between January 2018 and December 2021. Indication of central fever was ascertained by review of clinical documentation. A generalized additive mixed model (GAMM) was used to model temperature as a function of time relative to bromocriptine initiation. We adjusted for potential confounding due to the following covariates: temperature recording method (invasive vs surface), concurrent antipyretic administration within 8h, and surface cooling device use within 4h of temperature measurement. Temperature-time function was modeled using a cubic spline with k = 10 knots. A total of 33 patients were included in the analysis (14 women; mean age: 50 y, standard deviation 14 y). Median dose of bromocriptine was 7.5mg (range 2.5-40) for a median of 13 d (range 5-160). Age and sex did not impact the function of temperature over time. Predicted temperatures were significantly (p < 0.05) higher by 0.4°C with invasive compared to surface recording methods, lower by 0.2°C in the presence of cooling device use and lower by 0.1°C with concurrent antipyretic use. On adjusted analysis with the GAMM, there was decline (p < 0.05) in temperature following bromocriptine initiation by - 0.3°C at 24h, - 0.5°C at 48h, and - 0.7°C at 72h. Bromocriptine use was associated with modest but statistically significant decline in temperature, with nadir at 72h post initiation. The findings provide a data driven basis for prospective evaluation.