To the editor;
We have read with great interest the article published by Somuncu et al. which was about the association between obstructive sleep apnea (OSA) and subclinical atherosclerosis. It is impressed in the article that; prevalance of mixed/calcified coronary plaques is significantly higher in patients with OSA than healthy counterparts and atherosclerotic plaque burden is correlated with OSA severity.1
There are conflicting results about the relationship between hypothyroidism and OSA. Although the general opinion is; the frequency of hypothyroidism in patients with OSA is similar with general population and there are controversial data that implies that hypothyrodism is both more frequent in patients with OSA and cause of OSA. Hira et al. reported that OSA is more frequent in patients with hypothyroidism.2 It is reported in another study that it is not recommended to screen thyroid function tests routinely in patients with OSA. Thyroid replacement therapy improves OSA related symptoms but it may take one year period for disappearence of snore.3 Hypothyroidism is also related with dyslipidemia and metabolic syndrome. Triglyceride levels are higher in patients with hypothyroidism. Both hypothyroidism itself and hypothyroidism related hypertriglyceridemia can cause and accelerate atherosclerosis.4 Correlation between OSA and subclinical atherosclerosis was also demonstrated by another study which is reported by Kent et al. It is impressed that OSA is a predictor of subclinical atherosclerosis after adjusting the parameters including fasting plasma glucose and dyslipidemia.5
We think that, thyroid functions is associated with both OSA and atherosclerosis. It could be better if thyroid functions were evaluated.
REFERENCES
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