Howard Connie, Mukadam Naaheed, Hui Esther K, Livingston Gill
Division of Psychiatry, University College London, UK.
Division of Psychiatry, University College London, UK; Camden and Islington NHS Foundation Trust, UK.
Sleep Med. 2024 Dec;124:522-530. doi: 10.1016/j.sleep.2024.10.022. Epub 2024 Oct 20.
Sleep duration's association with future dementia could be a cause or consequence, or both. We searched electronic databases on 14 April 2023 for primary peer-reviewed, longitudinal studies examining the relationship between sleep duration and dementia with any follow-up duration. We meta-analysed studies examining brief (≤6 h/night) and extended sleep duration (≥9 h/night) separately and divided the studies into those with follow-up periods of less or more than 10 years. The quality of evidence was assessed using the Newcastle-Ottawa scale. 31 studies fulfilled the inclusion criteria. For brief sleep duration, a meta-analysis of short follow-up studies (≤10 years) found a 46 % increased risk of future dementia (relative risk [RR] - 1·46; 95 % Confidence Intervals [CIs] 1·48-1·77; I = 88·92 %, 6 studies). Studies with long follow-ups (>10 years) did not show a significantly increased risk (RR - 1·12; 0·95-1·29; I = 65·91 %; 5 studies). For extended sleep duration, a meta-analysis of short and long follow-up studies reported an increased risk of dementia (respectively RR - 2·20; 1·11-3·3; I = 94·17 %; 4 studies and RR - 1·74; 1·30-2·18; I = 86·56 %; 4 studies). Our findings suggest that brief sleep duration might be a prodromal symptom but not a risk factor of dementia. Extended sleep duration may be a risk factor. However, our results had high heterogeneity limiting external validity and generalisability.
睡眠时间与未来患痴呆症之间的关联可能是原因，也可能是结果，或者两者皆是。我们于2023年4月14日检索了电子数据库，以查找经同行评审的原发性纵向研究，这些研究考察了睡眠时间与痴呆症之间的关系，随访时长不限。我们分别对考察短睡眠时间（≤6小时/晚）和长睡眠时间（≥9小时/晚）的研究进行了荟萃分析，并将研究分为随访期少于或多于10年的两类。使用纽卡斯尔-渥太华量表评估证据质量。31项研究符合纳入标准。对于短睡眠时间，对随访期较短（≤10年）的研究进行的荟萃分析发现，未来患痴呆症的风险增加了46%（相对风险[RR] - 1.46；95%置信区间[CI] 1.48 - 1.77；I² = 88.92%，6项研究）。随访期较长（>10年）的研究未显示风险显著增加（RR - 1.12；0.95 - 1.29；I² = 65.91%；5项研究）。对于长睡眠时间，对随访期短和长的研究进行的荟萃分析均报告痴呆症风险增加（分别为RR - 2.20；1.11 - 3.3；I² = 94.17%；4项研究和RR - 1.74；1.30 - 2.18；I² = 86.56%；4项研究）。我们的研究结果表明，短睡眠时间可能是痴呆症的前驱症状，但不是风险因素。长睡眠时间可能是一个风险因素。然而，我们的结果具有高度异质性，限制了外部有效性和可推广性。
