Serum ferritin and obstructive sleep apnea-epidemiological study.

• Published in: Sleep and Breathing
• Main Authors: Thorarinsdottir, Elin H, Arnardottir, Erna S, Benediktsdottir, Bryndis, Janson, Christer, Olafsson, Isleifur, Pack, Allan I, Gislason, Thorarinn, Keenan, Brendan T
• Other Authors: 1 Faculty of Medicine, The National University of Iceland, Reykjavík, Iceland. 2 Sleep Department (E7), Landspitali-The National University Hospital of Iceland, 108, Reykjavík, Iceland. 3 Department of Medical Sciences: Respiratory, Allergy and Sleep Research, Uppsala University, Uppsala, Sweden. 4 Department of Clinical Biochemistry, Landspitali-The National University Hospital of Iceland, Reykjavík, Iceland. 5 Center for Sleep and Circadian Neurobiology and Division of Sleep Medicine/ Department of Medicine, University of Pennsylvania School of Medicine, Philadelphia, PA, USA. 6 Faculty of Medicine, The National University of Iceland, Reykjavík, Iceland. [e-mail]. 7 Sleep Department (E7), Landspitali-The National University Hospital of Iceland, 108, Reykjavík, Iceland. [e-mail].
• Format: Article in Journal/Newspaper
• Language: English
• Published: Springer Heidelberg 2018
• Subjects: BOLD; Ferritin; ISAC; Inflammation; OSA; Járn (næringarefni); Kæfisvefn; Ferritins; Sleep Apnea; Obstructive; Iceland
• Online Access: http://hdl.handle.net/2336/620710; https://doi.org/10.1007/s11325-017-1598-y

To access publisher's full text version of this article click on the hyperlink below Ferritin is an intracellular iron storage protein and a marker of inflammation. Studies have shown that subjects with obstructive sleep apnea (OSA) have higher levels of circulating pro-inflammatory cytokines, but little is known about the association between ferritin and OSA. The aims of the study were to evaluate serum ferritin (S-Ferritin) levels in OSA patients compared to levels in the general population and also examine the effect of obesity level and treatment with positive airway pressure (PAP) on S-Ferritin levels. The OSA subjects (n = 796) were part of the Icelandic Sleep Apnea Cohort. The control subjects (n = 637) were randomly chosen Icelanders who participated in an epidemiological study. Propensity score (PS) methodologies were employed to minimize selection bias and strengthen causal inferences when comparing non-randomized groups. S-Ferritin levels were measured and all participants answered the same detailed questionnaire about sleep and health. Only OSA patients underwent a sleep study and were re-invited for a 2-year follow-up. S-Ferritin levels were significantly higher in OSA males than controls (213.3 vs. 197.3 μg/L, p = 0.007). However, after adjusting for confounders and using our PS methodology, no significant difference was found. S-Ferritin levels were not correlated with severity of OSA, obesity level, or clinical symptoms. Also, no significant change in S-Ferritin levels was found with 2 years of PAP treatment. S-Ferritin levels are comparable in OSA patients and controls and do not change consistently with obesity level or PAP treatment in our sample. NIH Eimskip Fund of the University of Iceland Landspitali University Hospital Research Fund