We found a match
Your institution may have rights to this item. Sign in to continue.
- Title
The effect of levothyroxine replacement on PON1 activity in patients with subclinical hypothyroidism.
- Authors
Dag, Ömer Faruk; Tabur, Suzan; Eren, Mehmet Ali; Aksoy, Nurten; Sabuncu, Tevfik; Torun, Ayse Nur
- Abstract
Background: Subclinical hypothyroidism (SCH) is known to be related with atherosclerosis and coronary artery disease, and cardiovascular mortality is increased in patients with SCH. Paraoxonase/arylesterase (PON1) is a high-density lipoprotein (HDL) associated enzyme which prevents lipid peroxidation. The association between PON1 activity and atherosclerosis in SCH is not clear and need to be evaluated. We aimed to assess PON1 activity in SCH patients, and to determine the effect of levothyroxine replacement on PON1 activity and lipid profile. Methods: Thirty-nine patients with SCH having TSH levels between 4.2-10 µlU/L were included. Subjects were divided into three groups in order to their need for levothyroxine replacement, treatment group (n=19), without treatment (n=20) and control groups (n=20). Samples for total cholesterol (TC), LDL cholesterol (LDL-C), HDL cholesterol (HDL-C), triglyceride (TG), paraoxonase and arylesterase were determined from all subjects at the beginning of the study. Levothyroxine 50 µg/day was started to the subjects in the treatment group. All of the laboratory parameters were repeated after one month in both treatment and without treatment groups. Results: The initial demographic characteristics and TC, HDL-C, TG, paraoxonase and arylesterase levels of each group were similar. TSH level, paraoxonase and arylesterase activities significantly decreased in the treatment group after one month (p<0,001; p = 0,008; p<0,001, respectively). In the group without treatment a significant decrease was observed for only paraoxonase activity (p = 0,009). Levothyroxine replacement did not exert a significant effect on lipid profile. Conclusion: Although it seems that PON1 activity is not affected in patients with SCH who do not have very high TSH levels, levothyroxine replacement alters oxidant/antioxidant balance. It is not clear whether these alterations occur at which level of TSH increase. Further and long-term studies are needed to understand this and to determine the effect of levothyroxine replacement in SCH patients.
- Publication
Journal of Harran University Medical Faculty / Harran Üniversitesi Tıp Fakültesi Dergisi, 2011, Vol 8, Issue 2, p59
- ISSN
1304-9623
- Publication type
Journal Article