OBJECTIVES:
Basic science and clinical studies suggest that sleep disturbance may be a modifiable risk factor for post-operative delirium (POD). We aimed to assess the association between pre-operative sleep disturbance and POD.
DATA SOURCES:
We searched PubMed, Embase, CINAHL, Web of Science, and Cochrane from inception until May 31st, 2017.
STUDY SELECTION:
We performed a systematic search of the literature for all studies that reported on sleep disruption and POD excluding cross-sectional studies, case reports and studies not reported in English language.
DATA EXTRACTION:
Two authors independently performed study selection and data extraction. We calculated pooled effects estimates with a random-effects model constructed in Stata® and evaluated the risk of bias by formal testing (Stata® Corp V.14, Texas, USA),
DATA SYNTHESIS:
We included 12 studies, from 1,238 citations that met our inclusion criteria. The pooled odds ratio for the association between sleep disturbance and POD was 5.24 (95% CI: 3.61 to 7.60, p <0.001; I2=0.0%, p=0.76). The pooled risk ratio for the association between sleep disturbance and POD in prospective studies (n = 6) was 2.90 (95% CI: 2.28 to 3.69, p <0.001; I2=0.0%, p=0.89). The odds ratio associated with obstructive sleep apnea and unspecified types of sleep disorder were 4.75 (95% CI: 2.65 to 8.54, p <0.001; I2=0.0%, p=0.85), and 5.60 (95% CI: 3.46 to 9.07, p <0.001; I2=0.0%, p=0.41), respectively. We performed Begg’s and Egger tests for publication bias and confirmed a null result for publication bias (P = .371 and .103, respectively).
CONCLUSIONS:
Pre-existing sleep disturbances are likely associated with POD. Whether system-level initiatives targeting patients with pre-operative sleep disturbance may help reduce the prevalence, morbidity and healthcare costs associated with POD remains to be determined.
