Subclinical Hypothyroidism and the Risk of Hypercholesterolemia

Article Figures & Data

Table 1.

Demographics of the Sample Population

Characteristic	Subclincal Hypothyroidism(n = 215) No. (%)	Control (n = 8,013) No. (%)	PValue
Note: Percentages are weighted totals using SUDAAN to account for the complex sampling design of the NHANES III.
Sex			<.01
Male	72 (27.4)	3,890 (47.9)
Female	143 (72.6)	4,123 (52.1)
Race			<.01
Non-Hispanic white	142 (90.0)	4,025 (80.5)
Non-Hispanic black	20 (3.2)	1,916 (9.1)
Mexican-American	43 (3.0)	1,751 (3.5)
Other	10 (3.8)	321 (6.9)
Age			<.01
40–49 y	29 (23.0)	2,294 (37.9)
50–59 y	35 (17.3)	1,580 (24.1)
60–69 y	45 (23.4)	1,865 (20.4)
70–79 y	64 (27.7)	1,338 (12.8)
>80 y	42 (8.6)	936 (4.8)

Table 2.

Mean Lipid Values for Respondents with Subclinical Hypothyroidism and Controls

Lipids	Subclincal Hypothyroidism (n = 215) Mean (SD)	Control (n = 8,013) Mean (SD)	PValue
Total cholesterol, mg/dL	226.0 (44.2)	217.1 (43.7)	.003
High-density lipoprotein, mg/dL	50.9 (16.9)	50.9 (16.3)	.99
Low-density lipoprotein, mg/dL	139.7 (42.7)	136.2 (38.3)	.19
Triglycerides, mg/dL	178.1 (99.7)	157.5 (114.7)	.01

Table 3.

Comparison of Serum Lipid Profiles in Respondents with Subclinical Hypothyroidism and Controls

Lipids	Subclincal Hypothyroidism (n = 215) No. (%)	Control (n = 8,013) No. (%)	PValue
*Not all respondents had triglyceride determinations. Note: Percentages are weighted totals using SUDAAN to account for the complex sampling design of the NHANES III.
Total cholesterol			.02
>200 mg/dL	160 (74.2)	5,134 (63.9)
≤200 mg/dL	55 (25.8)	2,879 (36.1)
High-density lipoprotein			.08
<35 mg/dL	33 (9.9)	1,212 (15.3)
≤35 mg/dL	182 (90.1)	6,081 (84.7)
Lwo-density lipoprotein			.58
>130 mg/dL	62 (25.7)	1,892 (23.9)
≤130 mg/dL	153 (74.3)	6,121 (76.2)
Triglycerides *			.09
>250 mg/dL	39 (20.8)	1,034 (13.9)
≤250 mg/dL	176 (79.2)	6,979 (86.1)

Table 4.

Risk of Lipid Abnormality With Subclinical Hypothyroidism Adjusted for Potential Confounders

Lipids	Adjusted Relative Risk*	95% Confidence Interval
Adjusted with multivariate logistic regression for patient sex, race, age, and whether patient was taking a cholesterol-lowering medication.
Cholesterol >200 mg/dL	1.06	0.57–1.97
Low-density lipoprotein >130 mg/dL	0.89	0.59–1.35
High-density lipoprotein <35 mg/dL	0.94	0.36–2.48
Triglyceride >250 mg/dL	1.83	0.87–3.85

The Article in Brief

Hypothyroidism is a condition in which there is too little thyroid hormone circulating in the body. People with subclinical hypothyroidism have normal levels of thyroid hormone in circulation, but their thyroid-stimulating hormone is a little too high. Although hypothyroidism may lead to increased cholesterol levels, subclinical hypothyroidism does not lead to increased levels of cholesterol or triglycerides.