Features of dyslipidemia in chronic obstructive pulmonary disease and its combination with concomitant hypothyroidism

Systemic inflammation and external respiration dysfunction lead to blood lipid profile shift. As the frequent concomitant pathology, hypothyroidism causes lipid metabolism deviations as well. In this study, we aimed to investigate lipid metabolism features in chronic obstructive pulmonary disease including the presence of concomitant hypothyroidism. A direct method for determining total cholesterol and high- and low-density lipoproteins in blood serum, an enzymatic method for determining triacylglycerols in serum, automatic counting of the absolute number of the peripheral blood monocytes by a hematology analyzer, a fluorescent immunoassay method for determining thyroid-stimulating hormone and free thyroxine in serum were used all patients underwent postbroncho­dilator forced spirometry using a portable spirometer to obtain forced expiratory volume in the first second and forced vital capacity. There were assesed 65 patients with chronic obstructive pulmonary disease, 43 of them without con­comitant hypothyroidism (research group A), and the other 22 – with concomitant hypothyroidism (research group B); and 24 healthy controls examined as well. Comparing to controls, both research groups had significantly higher levels of total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol and triacylglycerols (p<0.05 for each parameter). Research group B patients had significantly higher serum concentrations of total cholesterol, low-density lipoprotein cholesterol and triacylglycerols and lower – of high-density lipoprotein cholesterol (p<0.05 for each), compared with research group A. Forward stepwise regression revealed that forced vital capacity decrease could be associated with total cholesterol content rise in all patients (p<0.001). We ascertained a negative correlation between total cholesterol level and forced expiratory volume during the first second, and also between total cholesterol level and forced vital capacity in both research groups (p<0.05). We also established a significant relationship between increased thyroid-stimulating hormone levels and increased total cholesterol concentrations based on stepwise regression analysis (p<0.001). A calculated monocyte-to-high density lipoprotein cholesterol ratio is perspective prognostic indicator of development of the final result of dyslipidemia – atherosclerosis, it was higher in the research group of patients with COPD and comorbidity (p<0.05). Investigation of blood lipid profile and the aforementioned index not only illustrates pathogenetic mutual burden of respiratory and thyroid pathologies, but also gives an opportunity to predict clinical parameters in chronic obstructive pulmonary disease patients like state of external ventilation function of lungs and cardiovascular risk.