Hypothyroidism is associated with increased intestinally derived lipoprotein particles and postprandial endothelial dysfunction
A. McGowan, W. Widdowson, G. Boran & J. Gibney
Atheroma is accelerated in overt hypothyroidism (OH) and possibly in subclinical-hypothyroidism (SCH), and is not completely explained by increased LDL-cholesterol. There is little data available regarding post-prandial metabolic changes in OH or SCH.
Subjects with OH (n=21), SCH (n=28) and age, sex and BMI matched controls (n=50) were studied fasting and for up to 8-h following a mixed-meal. Investigations included apolipoprotein(apo)B48, a marker of intestinally-derived lipoproteins, and flow-mediated-dilatation (FMD) of the brachial artery, a measure of endothelial dysfunction.
Under fasting conditions, lipid variables and FMD did not differ between groups. Data from SCH subjects were similar to normal subjects and are not shown. Triglyceride concentrations increased similarly in all groups postprandially, while apoB48 levels increased more markedly and significantly in overtly hypothyroid subjects compared to fasting conditions. FMD decreased significantly postprandially in the OH group only. At the 4-h time-point, apoB48 and FMD differed significantly between OH and normal subjects.
Intestinally-derived lipoprotein particles are increased and endothelial function impaired post-prandially in overt but not sub-clinically hypothyroid patients.
Declaration of interest: The authors declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project.
Funding: This work was supported, however funding details unavailable.