Received February 15, 2008
Accepted on April 27, 2008

ORIGINAL ARTICLES

Prevalence of Subclinical Hypothyroidism in Patients with Chronic Kidney Disease

Michel Chonchol ^*1, Giuseppe Lippi , Gianluca Salvagno , Giacomo Zoppini , Michele Muggeo , and Giovanni Targher

*Division of Renal Diseases and Hypertension, University of Colorado Health Sciences Center, Denver, Colorado; Section of Clinical Chemistry, Department of Biomedical and Morphological Sciences, and Section of Endocrinology, Department of Biomedical and Surgical Sciences, University Hospital of Verona, Verona, Italy

¹ To whom correspondence should be addressed. E-mail: Michel.Chonchol{at}uchsc.edu.

	Abstract

Background and objectives: Subclinical primary hypothyroidism is highly prevalent in the general population, especially in the elderly. However, the prevalence of subclinical primary hypothyroidism in persons with chronic kidney disease (CKD) not requiring chronic dialysis is not well defined.

Design, setting, participants, and measurements: Cross-sectional data from 3089 adult outpatients, who were consecutively referred by general practitioners for routine blood testing over the last two years, were analyzed. Glomerular filtration rate (GFR) was estimated by the abbreviated Modification of Diet in Renal Disease equation. Multivariable logistic regression was used to evaluate the independent association between prevalent subclinical primary hypothyroidism and estimated GFR.

Results: Among 3089 adult participants, 293 (9.5%) had subclinical primary hypothyroidism and 277 (9%) had an estimated GFR <60 ml/min per 1.73 m². The prevalence of subclinical primary hypothyroidism increased from 7% at an estimated GFR 90 ml/min per 1.73 m² to 17.9% at an estimated GFR <60 ml/min per 1.73 m² (P < 0.0001 for trend). Compared with participants with an estimated GFR 60 ml/min per 1.73 m², those with estimated GFR <60 ml/min per 1.73 m² had an increased odds of subclinical primary hypothyroidism after adjusting for age, gender, fasting plasma glucose, total cholesterol, and triglyceride concentrations.

Conclusions: These findings suggest that subclinical primary hypothyroidism is a relatively common condition (18%) among persons with CKD not requiring chronic dialysis, and it is independently associated with progressively lower estimated GFR in a large cohort of unselected outpatient adults.