Review article: Environmental heatstroke and long‐term clinical neurological outcomes: A literature review of case reports and case series 2000–2016

Abstract Global temperatures are rising; extreme environmental heat can result in adverse health effects including heatstroke. Acute effects of heat are well recognised, but there is less understanding of potential long‐term adverse outcomes. Our aim was to review recent medical literature for clinical cases of environmental heatstroke with a focus on neurological outcome. Structured search strategies were designed to retrieve publications of heatstroke case reports using Ovid Medline and Embase (2000–2016). One thousand and forty‐nine abstracts were identified, and after application of exclusion criteria 71 articles deemed relevant. Ninety cases were identified from 71 articles. 100% presented with acute neurological symptoms; 87.8% presented with non‐neurological symptoms. 44.4% patients recovered fully, 23.3% died, 23.3% suffered convalescent or long‐term neurological sequelae, and in 8.9% no long‐term follow up was available. 57.1% of the patients who died or had a neurological deficit had no documented co‐morbidity. Patterns of neurological deficits included 66.7% patients with motor dysfunction, 9.5% cognitive impairment, 19% both motor and cognitive impairment and 4.7% other. In total 71.4% of the impaired patients had long‐term cerebellar dysfunction. Adverse long‐term neurological outcomes were common in surviving patients presenting with environmental heatstroke. Permanent neurological deficits were present in 34.4% of survivors where outcome was known; many were young, healthy individuals. Cerebellar injury was common suggesting cerebellar structures are vulnerable to heat. These findings highlight that people of all ages and pre‐morbid states are at risk of severe heat‐related illness. In the face of climate change, effective interventions for heat‐related illness, including both treatment and prevention are necessary.