Effect of Levo-Thyroxine Replacement on Non-High-Density Lipoprotein Cholesterol in Hypothyroid Patients

Background: The thyroid hormones are involved in controlling metabolism, growth and functions of various organ systems of our body. Hypothyroidism, a very common endocrinopathy features reduced production of thyroid hormones. In hypothyroidism we encounter abnormal circulating lipid fractions which is termed as ‘Dyslipidemia’. The coexistence of dyslipidemia and hypothyroidism is associated with development of atherosclerosis. Aim: This research is undertaken to assess the potential of TC/HDL-C ratio to disclose dyslipidemia in hypothyroidism. Methodology: The study consists of two major groups, the ‘Cases’ comprising of Fifty hypothyroid patients and ‘Controls’, with fifty age and gender matched healthy adults. The Cases are further subdivided into Twenty ‘Known cases’ of Hypothyroid patients, already receiving treatment and thirty ‘New cases’. The ‘New cases’ sub group further is subdivided as Twenty-one ‘Overt hypothyroids’(OH) and nine ‘Subclinical Hypothyroids’ (SCH). The Biochemical parameters estimated in all subjects of the study includes, Serum TSH, T3, T4, Total Cholesterol (TC) and High density lipoprotein-cholesterol(HDL-C). TC/HDL ratio was then calculated . Result: The study shows a significant elevation (p = 0.05) in the TC/HDL-C ratio in hypothyroid patients (3.67 ± 1.02) when compared to healthy controls (3.29 ± 0.95). TC/HDL-C ratio is more elevated in OH (4.01 ± 1.28) than in SCH (3.46 ± 0.92). The levels in ‘New cases’ sub-group and OH sub sub group have significantly higher ratio than in healthy controls (p = 0.02 and p = 0.01 respectively). TC/HDL-C ratio value in “known cases’ group who are those hypothyroid patients on Levo-thyroxine therapy is (3.40 ± 0.61) less than those who are newly diagnosed. Conclusion: TC/HDL-C ratio is not only raised in hypothyroid patients but it is seen increasing with severity and prolonged duration of disease. The calculation of TC/HDL-C ratio should be routinely put into practice to detect hypothyroid patients with dyslipidemia.

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Triglyceride to high density lipoprotein cholesterol ratio, total cholesterol to high density lipoprotein cholesterol ratio and low ankle brachial index in an elderly population

VASA ◽

10.1024/0301-1526/a000348 ◽

2014 ◽

Vol 43 (3) ◽

pp. 189-197 ◽

Cited By ~ 10

Author(s):

Yiqiang Zhan ◽

Jinming Yu ◽

Rongjing Ding ◽

Yihong Sun ◽

Dayi Hu

Keyword(s):

High Density Lipoprotein ◽

Total Cholesterol ◽

High Density Lipoprotein Cholesterol ◽

Ankle Brachial Index ◽

Density Lipoprotein ◽

High Density ◽

Lipoprotein Cholesterol ◽

Lipid Lowering ◽

Cholesterol Ratio ◽

Potential Biomarker

Background: The associations of triglyceride (TG) to high-density lipoprotein cholesterol ratio (HDL‑C) and total cholesterol (TC) to HDL‑C ratio and low ankle brachial index (ABI) were seldom investigated. Patients and methods: A population based cross-sectional survey was conducted and 2982 participants 60 years and over were recruited. TG, TC, HDL‑C, and low-density lipoprotein cholesterol (LDL-C) were assessed in all participants. Low ABI was defined as ABI ≤ 0.9 in either leg. Multiple logistic regression models were applied to study the association between TG/HDL‑C ratio, TC/HDL‑C ratio and low ABI. Results: The TG/HDL‑C ratios for those with ABI > 0.9 and ABI ≤ 0.9 were 1.28 ± 1.20 and 1.48 ± 1.13 (P < 0.0001), while the TC/HDL‑C ratios were 3.96 ± 1.09 and 4.32 ± 1.15 (P < 0.0001), respectively. After adjusting for age, gender, body mass index, obesity, current drinking, physical activity, hypertension, diabetes, lipid-lowering drugs, and cardiovascular disease history, the odds ratios (ORs) with 95 % confidence intervals (CIs) of low ABI for TG/HDL‑C ratio and TC/HDL‑C ratio were 1.10 (0.96, 1.26) and 1.34 (1.14, 1.59) in non-smokers. When TC was further adjusted, the ORs (95 % CIs) were 1.40 (0.79, 2.52) and 1.53 (1.21, 1.93) for TG/HDL‑C ratio and TC/HDL‑C ratio, respectively. Non-linear relationships were detected between TG/HDL‑C ratio and TC/HDL‑C ratio and low ABI in both smokers and non-smokers. Conclusions: TC/HDL‑C ratio was significantly associated with low ABI in non-smokers and the association was independent of TC, TG, HDL‑C, and LDL-C. TC/HDL‑C might be considered as a potential biomarker for early peripheral arterial disease screening.

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