Anupam Kotwal1,2, Tiffany Cortes3, Natalia Genere4, Oksana Hamidi5, Sina Jasim6, Connie B Newman7, Larry J Prokop8, M Hassan Murad1, Fares Alahdab1. 1. Evidence-Based Practice Center, Mayo Clinic, Rochester, Minnesota. 2. Division of Diabetes, Endocrinology and Metabolism, University of Nebraska Medical Center, Omaha, Nebraska. 3. Division of Endocrinology, University of Texas, San Antonio, Texas. 4. Division of Endocrinology, Diabetes, Metabolism and Nutrition, Mayo Clinic, Rochester, Minnesota. 5. Division of Endocrinology and Metabolism, University of Texas Southwestern Medical Center, Dallas, Texas. 6. Division of Endocrinology, Metabolism and Lipid Research, Washington University, St. Louis, Missouri. 7. Department of Medicine, Division of Endocrinology, Diabetes, and Metabolism, New York University School of Medicine, New York, New York. 8. Mayo Clinic Libraries, Mayo Clinic, Rochester, Minnesota.
Abstract
CONTEXT: Hyperthyroidism is associated with low levels of cholesterol and triglycerides, and hypothyroidism is associated with hypercholesterolemia and hypertriglyceridemia. OBJECTIVE: The aim of this systematic review was to investigate the impact of therapy for overt and subclinical hyper- and hypothyroidism on serum lipids. DATA SOURCES: We searched MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials, the Cochrane Database of Systematic Reviews, and Scopus from 1970 through April 5, 2018. STUDY SELECTION: Pairs of independent reviewers selected randomized and observational studies evaluating lipid parameters in patients undergoing treatment for hyper- or hypothyroidism. DATA EXTRACTION: Pairs of independent reviewers extracted data and appraised studies. DATA SYNTHESIS: Treatment of overt hyperthyroidism showed a significant increase in total cholesterol (TC) by 44.50 mg/dL (95% confidence interval [CI]: 37.99, 51.02), low-density lipoprotein cholesterol (LDL-C) by 31.13 mg/dL (95% CI: 24.33, 37.93), high-density lipoprotein cholesterol (HDL-C) by 5.52 mg/dL (95% CI: 1.48, 9.56), apolipoprotein A (Apo A) by 15.6 mg/dL (95% CI: 10.38, 20.81), apolipoprotein B (apo B) by 26.12 mg/dL (95% CI: 22.67, 29.57), and lipoprotein (Lp[a]) by 4.18 mg/dL (95% CI: 1.65, 6.71). There was no significant change in triglyceride (TG) levels. Treatment of subclinical hyperthyroidism did not change any lipid parameters significantly. Levothyroxine therapy in overt hypothyroidism showed a statistically significant decrease in TC by -58.4 mg/dL (95% CI: -64.70, -52.09), LDL-C by -41.11 mg/dL (95% CI: -46.53, -35.69), HDL-C by -4.14 mg/dL (95% CI: -5.67, -2.61), TGs by -7.25 mg/dL (95% CI: -36.63, 17.87), apo A by -12.59 mg/dL (95% CI: -17.98, -7.19), apo B by -33.96 mg/dL (95% CI: 41.14, -26.77), and Lp(a) by -5.6 mg/dL (95% CI: -9.06, -2.14). Levothyroxine therapy in subclinical hypothyroidism showed similar changes but with a smaller magnitude. The studies contained varied population characteristics, severity of thyroid dysfunction, and follow-up duration. CONCLUSIONS: Treatment of overt but not subclinical hyperthyroidism is associated with worsening of the lipid profile. Levothyroxine therapy in both overt and subclinical hypothyroidism leads to improvement in the lipid profile, with a smaller magnitude of improvement in subclinical hypothyroidism.
CONTEXT: Hyperthyroidism is associated with low levels of cholesterol and triglycerides, and hypothyroidism is associated with hypercholesterolemia and hypertriglyceridemia. OBJECTIVE: The aim of this systematic review was to investigate the impact of therapy for overt and subclinical hyper- and hypothyroidism on serum lipids. DATA SOURCES: We searched MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials, the Cochrane Database of Systematic Reviews, and Scopus from 1970 through April 5, 2018. STUDY SELECTION: Pairs of independent reviewers selected randomized and observational studies evaluating lipid parameters in patients undergoing treatment for hyper- or hypothyroidism. DATA EXTRACTION: Pairs of independent reviewers extracted data and appraised studies. DATA SYNTHESIS: Treatment of overt hyperthyroidism showed a significant increase in total cholesterol (TC) by 44.50 mg/dL (95% confidence interval [CI]: 37.99, 51.02), low-density lipoprotein cholesterol (LDL-C) by 31.13 mg/dL (95% CI: 24.33, 37.93), high-density lipoprotein cholesterol (HDL-C) by 5.52 mg/dL (95% CI: 1.48, 9.56), apolipoprotein A (Apo A) by 15.6 mg/dL (95% CI: 10.38, 20.81), apolipoprotein B (apo B) by 26.12 mg/dL (95% CI: 22.67, 29.57), and lipoprotein (Lp[a]) by 4.18 mg/dL (95% CI: 1.65, 6.71). There was no significant change in triglyceride (TG) levels. Treatment of subclinical hyperthyroidism did not change any lipid parameters significantly. Levothyroxine therapy in overt hypothyroidism showed a statistically significant decrease in TC by -58.4 mg/dL (95% CI: -64.70, -52.09), LDL-C by -41.11 mg/dL (95% CI: -46.53, -35.69), HDL-C by -4.14 mg/dL (95% CI: -5.67, -2.61), TGs by -7.25 mg/dL (95% CI: -36.63, 17.87), apo A by -12.59 mg/dL (95% CI: -17.98, -7.19), apo B by -33.96 mg/dL (95% CI: 41.14, -26.77), and Lp(a) by -5.6 mg/dL (95% CI: -9.06, -2.14). Levothyroxine therapy in subclinical hypothyroidism showed similar changes but with a smaller magnitude. The studies contained varied population characteristics, severity of thyroid dysfunction, and follow-up duration. CONCLUSIONS: Treatment of overt but not subclinical hyperthyroidism is associated with worsening of the lipid profile. Levothyroxine therapy in both overt and subclinical hypothyroidism leads to improvement in the lipid profile, with a smaller magnitude of improvement in subclinical hypothyroidism.
Authors: G Corona; L Croce; C Sparano; L Petrone; A Sforza; M Maggi; L Chiovato; M Rotondi Journal: J Endocrinol Invest Date: 2021-05-25 Impact factor: 4.256
Authors: Thaer Idrees; Wesley H Prieto; Sabina Casula; Aswathy Ajith; Matthew Ettleson; Flavia A Andreotti Narchi; Pedro S T Russo; Fernando Fernandes; Julie Johnson; Anoop Mayampurath; Rui M B Maciel; Antonio C Bianco Journal: J Endocr Soc Date: 2021-03-06