Thyroid Dysfunction and Anemia: A Prospective Cohort Study and a Systematic Review.

Floriani, Carmen; Feller, Martin; Aubert, Carole E; M'Rabet-Bensalah, Khadija; Collet, Tinh-Hai; den Elzen, Wendy P J; Bauer, Douglas C; Angelillo, Anne; Aujesky, Drahomir; Rodondi, Nicolas (2018). Thyroid Dysfunction and Anemia: A Prospective Cohort Study and a Systematic Review. Thyroid, 28(5), pp. 575-582. Mary Ann Liebert 10.1089/thy.2017.0480

[img] Text
AAS_Tyroid Dysfunction and Anemia.pdf - Published Version
Restricted to registered users only
Available under License Publisher holds Copyright.

Download (158kB) | Request a copy

BACKGROUND Even though the association between thyroid dysfunction and anemia is commonly described, it is not known whether it is clinically relevant. This study set out to quantify the association of thyroid dysfunction on hemoglobin (Hb) concentration and risk of anemia. A systematic review (MEDLINE and EMBASE, from inception until May 15, 2017) was conducted to interpret the findings in context. METHODS Participants from the EPIC-Norfolk cohort with available baseline thyrotropin (TSH), free thyroxine (fT4), and Hb were included. Euthyroidism was defined as TSH 0.45-4.49 mIU/L (reference category), hypothyroidism as TSH ≥4.50 mIU/L (subclinical [SHypo] with normal fT4 or overt [OHypo] with low fT4), and hyperthyroidism as TSH ≤0.44 mIU/L (subclinical [SHyper] with normal fT4 or overt [OHyper] with elevated fT4). Anemia was defined as Hb <12 g/dL in women and Hb <13 g/dL in men. In the cross-sectional analyses, multiple linear regression was used to compare Hb across TSH categories. In the prospective analysis, participants with OHypo/OHyper at baseline were excluded, as it was assumed that they were treated for overt thyroid disease. A covariance model was used to determine change in Hb concentration from baseline to last follow-up, and multivariable Cox regression was used to analyze anemia risk. RESULTS In the cross-sectional population (n = 12,337), the adjusted Hb was 0.22 g/dL lower [confidence interval (CI) 0.07-0.38] in OHypo compared to euthyroids, and 0.08 g/dL lower [CI -0.23 to 0.38] in OHyper. In the prospective analysis, 460/7031 participants developed anemia over a median follow-up of 4.7 years. The adjusted mean Hb change over time was -0.04 g/dL in SHypo [CI -0.14 to 0.06] and 0.05 g/dL in SHyper [CI -0.10 to 0.20]. The adjusted hazard ratio for anemia was 0.99 [CI 0.67-1.48] in SHypo, and 0.52 [CI 0.23-1.16] in SHyper. The systematic review returned no other prospective studies on this association, but cross-sectional and case-control studies showed comparable results. CONCLUSION In this first prospective population-based cohort, subclinical thyroid dysfunction was not associated with a change in Hb concentration during follow-up and was not an independent risk factor for developing anemia; variations in Hb concentration in patients with overt thyroid dysfunction were not clinically relevant.

Item Type:

Journal Article (Original Article)

Division/Institute:

04 Faculty of Medicine > Department of General Internal Medicine (DAIM) > Clinic of General Internal Medicine > Centre of Competence for General Internal Medicine
04 Faculty of Medicine > Medical Education > Institute of General Practice and Primary Care (BIHAM)
04 Faculty of Medicine > Department of General Internal Medicine (DAIM) > Clinic of General Internal Medicine
04 Faculty of Medicine > Department of Haematology, Oncology, Infectious Diseases, Laboratory Medicine and Hospital Pharmacy (DOLS) > Clinic of Haematology and Central Haematological Laboratory
04 Faculty of Medicine > Pre-clinic Human Medicine > BioMedical Research (DBMR) > Unit Childrens Hospital > Forschungsgruppe Hämatologie (Erwachsene)

UniBE Contributor:

Floriani, Carmen; Feller, Martin; Aubert, Carole Elodie; Angelillo, Anne; Aujesky, Drahomir and Rodondi, Nicolas

Subjects:

600 Technology > 610 Medicine & health
300 Social sciences, sociology & anthropology > 360 Social problems & social services

ISSN:

1050-7256

Publisher:

Mary Ann Liebert

Language:

English

Submitter:

Pierrette Durand Lüthi

Date Deposited:

21 Aug 2018 11:41

Last Modified:

18 Sep 2018 11:41

Publisher DOI:

10.1089/thy.2017.0480

PubMed ID:

29631476

Additional Information:

Floriani and Feller contributed equally to this work.

Uncontrolled Keywords:

anemia clinical relevance hemoglobin prospective population-based cohort thyroid dysfuntion thyrotropin

BORIS DOI:

10.7892/boris.119395

URI:

https://boris.unibe.ch/id/eprint/119395

Actions (login required)

Edit item Edit item
Provide Feedback