Central cooling effects in patients with hypercholesterolaemia

Abstract

1. A prospective study has been carried out, and 68 patients with hypercholesterolaemia have been investigated to study the effects of central cooling on serum lipid levels. 2. Central cooling was obtained by the exposure of the whole body to cold water. All patients were trained to gradually reduce the water temperature from 22 to 14 degrees C and to increase the time of exposure from 5 to 20 min over a period of 90 days. The 33 male and 35 female patients were aged between 40 and 60 years at entry with total cholesterol of 6.0 mmol/l or greater and low-density lipoprotein (LDL)-cholesterol of 4. 0 mmol/l or greater. Thyroid-stimulating hormone, free thyroxine (FT4), total T3, total cholesterol, LDL-cholesterol, high-density lipoprotein (HDL)-cholesterol, triacylglycerols and total fat mass (determined by dual-energy X-ray absorptiometry scan) were obtained at baseline and after 3 months treatment with hydrotherapy. 3. Central cooling obtained by hydrotherapy results in a median fall in tympanic temperature from 0.2 degrees C (P<0.001) to 0.8 degrees C (P<0.001). We have observed in these patients a significant reduction in total cholesterol (-0.2 mmol/l, P=0.006) and LDL-cholesterol (-0.2 mmol/l, P=0.004). Serum FT4 level was higher than baseline results in 30 of these hypercholesterolaemic patients (15.5 pmol/l to 17.3 pmol/l) and there was no significant change in serum thyroid-stimulating hormone and total T3. 4. In conclusion, in our patients with hypercholesterolaemia we have observed a significant reduction of total cholesterol and LDL-cholesterol after body temperature regulation.

Could human cold adaptation decrease the risk of cardiovascular disease?

“…It may also have influenced the results obtained from our relatively small groups of subjects. Our data show that thyroid gland function changes after repeated cold exposure, which is in agreement with previous observations (De Lorenzo et al, 1998). By contrast, our results contradict a well-documented condition found in polar explorers (polar T3 syndrome), which is caused by alteration in the hypothalamic-thyroid axis, changes in T3 kinetics and decrease of plasmatic T3 concentration.…”

“…Only one study (De Lorenzo et al, 1998) has reported significant reduction of total and LDL cholesterol levels in a group of hypercholesterolaemic patients after 90 days of cold adaptation. Increased catecholamine secretion or altered sensitivity of catecholamine receptors could explain the decrease of total and LDL cholesterol after cold adaptation (De Lorenzo et al, 1998;Jansky et al, 2008). However, the opposite effect of corticosteroids should also be taken into account (Hermanussen et al, 1995).…”

Cardiovascular Manifestations Among Workers in Meat Production Exposed to Cold Environment

“…Also Meade and his co-authors (1993), demonstrated seasonal changes in low-density-lipoprotein cholesterol (LDL cholesterol) concentration, with peak levels in winter months and increase of total cholesterol as well. This in contrast to Lorenzo et al (1998) who reported a significant reduction of total and lowdensity lipoprotein (LDL) cholesterol in a group of patients with hypercholesterolemia after 90 days of cold adaptation.…”

Adipocyte Hypoxia-Inducible Factor 2α Suppresses Atherosclerosis by Promoting Adipose Ceramide Catabolism

“…Consistent with this protection, chronic mild cold exposure was reported to inhibit atherosclerosis through promoting plasma lipid clearance, decreasing inflammation, and improving endothelial dysfunction in an adipose-thermogenesis-dependent manner (Chang et al, 2012;Reyné s et al, 2017), while a chronic thermoneutral environment (30 C) aggravated atherosclerosis by promoting vascular inflammation (Tian et al, 2016). Improvement of hypercholesterolemia was also observed in humans after mild cold exposure (De Lorenzo et al, 1998). However, another study has shown that cold exposure promoted plaque instability (Dong et al, 2013).…”