Post‐stroke circadian rhythm disruption and stroke prognosis: A systematic review

Circadian rhythm disruption has been frequently reported in stroke patients. However, its impact on prognosis remains unclear. This systematic review aimed to: (i) comprehensively characterize circadian rhythm disruption following stroke, and (ii) evaluate its relationship with various outcomes among stroke patients. We performed a systematic literature search on 4th May 2024 across Embase, Medline, CINAHL, and the Cochrane Register of Controlled Trials, with additional articles identified through related reviews. A total of 50 studies were included in the qualitative synthesis with 28 characterizing circadian rhythms in stroke patients, and 30 evaluating the relationship with stroke prognosis. Most studies were rated as moderate (55%) or high quality (28%). Across all studies characterizing circadian rhythm disruption, 26 studies (93%) found evidence of circadian rhythm disruption in stroke patients measured using hormonal, autonomic, behavioral, and genetic circadian markers. Most included studies (27 studies; 90%) also found a positive association between circadian rhythm disruption and at least one indicator of poor prognosis among stroke patients including poorer functional outcomes, cognitive impairment, mood disorder, impaired consciousness, sleep disturbances, increased in‐hospital mortality, as well as other stroke‐related complications. These findings highlight the commonality of circadian rhythm disruption and the importance of circadian rhythm assessments among stroke patients. Our results showing the adverse impact of circadian rhythm disruption also support further investigation into novel circadian‐based therapeutic interventions to optimize stroke recovery. This systematic review was registered with PROSPERO (CRD42024539223).