title: Unresolved subclinical hypothyroidism is independently associated with progression of chronic kidney disease.
abstract: OBJECTIVE
  Patients with chronic kidney disease (CKD) often have subclinical hypothyroidism. However, few reports have investigated changes in the status of subclinical hypothyroidism in CKD patients and its clinical significance in CKD progression.
  
  
  METHODS
  We included 168 patients with nondialysis-dependent CKD stages 2-4. The normalization of subclinical hypothyroidism during follow-up was assessed, and the association between transitions in subclinical hypothyroid status and the rate of decline of the estimated glomerular filtration rate (eGFR) was investigated.
  
  
  RESULTS
  At baseline, 127 patients were euthyroid and 41 (24.4%) patients were diagnosed with subclinical hypothyroidism. Of these 41 patients, 21 (51.2%) spontaneously resolved to euthyroid during follow-up. The rate of eGFR decline of patients with resolved subclinical hypothyroidism was similar to that of euthyroid patients. The patients with unresolved subclinical hypothyroidism showed a steeper renal function decline than patients with euthyroidism or resolved subclinical hypothyroidism (all p < 0.05). The progression to end-stage renal disease was more frequent in those with unresolved subclinical hypothyroidism than in those who were euthyroid (p = 0.006). In multivariate linear regression for rate of eGFR decrease, unresolved subclinical hypothyroidism (β = -5.77, p = 0.001), baseline renal function (β = -0.12, p < 0.001) and level of proteinuria (β = -2.36, p = 0.015) were independently associated with the rate of renal function decline.
  
  
  CONCLUSIONS
  Half of the CKD patients with subclinical hypothyroidism did not resolve to euthyroidism, and this lack of resolution was independently associated with rapid renal function decline.
authors.affiliation: 1. Division of Nephrology, Departments of Internal Medicine, The Catholic University of Korea, Seoul, Korea.
authors.forename: Eun Oh
authors.initials: EO
authors.lastname: Kim
authors.affiliation: 2. Division of Endocrinology, Departments of Internal Medicine, The Catholic University of Korea, Seoul, Korea.
authors.forename: Ihn Suk
authors.initials: IS
authors.lastname: Lee
authors.affiliation: 1. Division of Nephrology, Departments of Internal Medicine, The Catholic University of Korea, Seoul, Korea.
authors.forename: Yoo A
authors.initials: YA
authors.lastname: Choi
authors.affiliation: 1. Division of Nephrology, Departments of Internal Medicine, The Catholic University of Korea, Seoul, Korea.
authors.forename: Sang Ju
authors.initials: SJ
authors.lastname: Lee
authors.affiliation: 1. Division of Nephrology, Departments of Internal Medicine, The Catholic University of Korea, Seoul, Korea.
authors.forename: Yoon Kyung
authors.initials: YK
authors.lastname: Chang
authors.affiliation: 1. Division of Nephrology, Departments of Internal Medicine, The Catholic University of Korea, Seoul, Korea.
authors.forename: Hye Eun
authors.initials: HE
authors.lastname: Yoon
authors.affiliation: 2. Division of Endocrinology, Departments of Internal Medicine, The Catholic University of Korea, Seoul, Korea.
authors.forename: Yi Sun
authors.initials: YS
authors.lastname: Jang
authors.affiliation: 2. Division of Endocrinology, Departments of Internal Medicine, The Catholic University of Korea, Seoul, Korea.
authors.forename: Jong Min
authors.initials: JM
authors.lastname: Lee
authors.affiliation: 2. Division of Endocrinology, Departments of Internal Medicine, The Catholic University of Korea, Seoul, Korea.
authors.forename: Hye Soo
authors.initials: HS
authors.lastname: Kim
authors.affiliation: 1. Division of Nephrology, Departments of Internal Medicine, The Catholic University of Korea, Seoul, Korea.
authors.forename: Chul Woo
authors.initials: CW
authors.lastname: Yang
authors.affiliation: 1. Division of Nephrology, Departments of Internal Medicine, The Catholic University of Korea, Seoul, Korea.
authors.forename: Suk Young
authors.initials: SY
authors.lastname: Kim
authors.affiliation: 1. Division of Nephrology, Departments of Internal Medicine, The Catholic University of Korea, Seoul, Korea.
authors.forename: Hyeon Seok
authors.initials: HS
authors.lastname: Hwang
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000959:Antihypertensive Agents / Q000627:therapeutic use; D005260:Female; D005500:Follow-Up Studies; D005919:Glomerular Filtration Rate; D006801:Humans; D007037:Hypothyroidism / Q000209:etiology*; D053208:Kaplan-Meier Estimate; D007676:Kidney Failure, Chronic / Q000209:etiology; D008297:Male; D008875:Middle Aged; D051436:Renal Insufficiency, Chronic / Q000150:complications* / Q000401:mortality / Q000503:physiopathology*; D012307:Risk Factors
chemical_list: D000959:Antihypertensive Agents
keywords: chronic kidney disease; progression; subclinical hypothyroidism.