The relationship between obstructive sleep apnea and white coat hypertension has not been clearly delineated. The study by García-Río et al in this issue of CHEST is the first attempt to analyze this association. The authors designed a very simple study in which 99 patients with obstructive sleep apnea were divided into groups according to their BP status: normotensive subjects, patients with white coat hypertension, and patients with sustained hypertension. All these patients underwent several laboratory tests such as 24-h BP monitoring and urinary catecholamine measurement, while at the same time a polysomnographic study was performed. García-Río et al demonstrate that the prevalence of white coat hypertension in patients with sleep apnea is 33% (15 patients) and that these patients have higher values of sleep-onset latency and waking after sleep onset. In addition, in a logistic regression model gender, age, smoking, diabetes, sleep-onset latency, and waking after sleep onset were predictors of white coat hypertension. Although the data are interesting, there are many questions and limitations that arise from this study. First, the difference in the sleep patterns between patients with white coat hypertension and hypertension do not have any clinical meaning, since we certainly do not know the characteristics of sleep in patients with white coat hypertension. It would have been more consequential to perform polysomnographic studies in patients with white coat hypertension and to define the sleep pattern of these patients. The latter has never been explored. It is possible that one of the reasons that patients had white coat hypertension is the fact that they have undiagnosed sleep apnea. Interestingly, in this article a great proportion of patients with sleep apnea and white coat hypertension consists of nondippers (73%). Second, will these data allow us to treat these patients differently? Third, should the conclusion of the article be applied just to patients with sleep apnea or just to patients with white coat hypertension? In other words, we do not know how many patients with white coat hypertension have sleep apnea. Finally, it seems that the authors propose to use ambulatory BP monitoring to assess the prevalence of white coat hypertension in patients with sleep apnea. Many of the patients with sleep apnea have hypertension, as the epidemiologic data have demonstrated, whether white coat or established, thus the sleep-breathing disorders should be treated, regardless, in order to improve cardiovascular complications and quality of life in these patients.