Iron deficiency (ID) is associated with sleep disorders, but standardized assessment of iron status in the diagnostic work-up and iron supplementation as treatment have not been considered in clinical practice. We investigated associations of ID with type and severity of sleep disorders and whether iron supplementation improves sleep-related symptoms. In 2017, we conducted a scoping review for the period 1972-2016 using the terms “iron deficiency anemia” and “sleep” on biomedical database search engines, and in 2019, we updated our review with an ad-hoc search. Among the 93 articles meeting our inclusion criteria, 74/93 studies investigated restless legs syndrome (RLS), 8/93 periodic limb movements in sleep (PLMs), 3/93 sleep disordered breathing (SDB), 6/93 general sleep disturbances (GSD), and 2/93 attention-deficit/ hyperactivity disorder related sleep disorders (ADHD-SDs). A statistically supported positive association with ID was found in 22/42 RLS, 3/8 PLMs, 1/2 SDB, 3/4 GSD, and 1/2 ADHD-SDs association studies. The ad-hoc literature search revealed eight additional association studies with a statistically supported positive association in 2/5 RLS, 1/1 SDB, 1/1 ADHD-SDs, and 1/1 restless sleep disorder (RSD) studies. Iron supplementation was beneficial in 29/30 RLS (including five randomized controlled trials [RCTs]), 1/1 SDB, and 2/2 GSD treatment studies. Iron supplementation was also beneficial in 2/2 RLS (including two RCTs), 1/1 GSD (RCT), and 1/1 RSD studies identified in the ad-hoc search. In pediatric populations, 1/1 RLS, 1/1 SDB, 2/5 PLMs, 2/3 GSD and 1/2 ADHD-SDs studies found positive associations, and 6/6 RLS and 2/2 GSD studies demonstrated a benefit with iron supplementation. In conclusion, iron investigation and supplementation should be considered in patients presenting with sleep disorders. To investigate the role of ID in sleep in the future, a harmonization of study designs, including outcome measures and standardized iron and inflammation status is necessary.

铁缺乏症（ID）与睡眠障碍有关，但是在临床实践中尚未考虑对诊断工作和补充铁剂进行标准化的铁质评估。我们调查了ID与睡眠障碍的类型和严重程度以及铁补充是否改善了睡眠相关症状之间的关系。2017年，我们在生物医学数据库搜索引擎上使用“缺铁性贫血”和“睡眠”一词对1972-2016年进行了范围界定审查，并在2019年通过临时搜索更新了该审查。在符合我们纳入标准的93篇文章中，74/93研究调查了不安腿综合征（RLS），8/93周期性肢体睡眠中的运动（PLM），3/93睡眠呼吸障碍（SDB），6/93的一般睡眠障碍（ GSD），和2/93注意缺陷/多动障碍相关的睡眠障碍（ADHD-SD）。在22/42 RLS，3/8 PLM，1/2 SDB，3/4 GSD和1/2 ADHD-SDs关联研究中发现了与ID有统计学支持的正相关。临时文献搜索显示，在2/5个RLS，1/1个SDB，1/1个A​​DHD-SD和1/1个躁动性睡眠障碍（RSD）研究中，有八项具有统计学支持的正相关的关联研究。铁补充在29/30 RLS（包括5个随机对照试验[RCT]），1/1 SDB和2/2 GSD治疗研究中是有益的。在临时搜索中确定的2/2 RLS（包括两个RCT），1/1 GSD（RCT）和1/1 RSD研究中，补铁也是有益的。在儿科人群中，1/1 RLS，1/1 SDB，2/5 PLM，2/3 GSD和1/2 ADHD-SDs发现存在正相关，6/6 RLS和2/2 GSD研究证明补铁有益。总之，患有睡眠障碍的患者应考虑铁的检查和补充。为了研究ID在未来睡眠中的作用，必须对研究设计进行统一，包括结果测量和标准化的铁和炎症状态。