To the Editor:
We would like to express our appreciation for the comments of Arias et al. As mentioned, our study did not analyze the presence of obstructive sleep apneahypopnea syndrome (OSAHS) and its possible relationship with patient mortality. It is true that a potential OSAHS was not actively investigated in a generalized manner; however, the history of this syndrome was compiled from the patients' demographic data despite the fact that such details were not listed in the article. In fact, only 18 patients had been diagnosed with OSAHS (3.6%). An analysis of these patients' data did not show significant differences in terms of 2-year mortality, despite the low number of patients with the syndrome (mortality of OSAHS patients, 16.6%; mortality of OSAHS-free patients, 22.3%; P=.57). It is also true that the prevalence of OSAHS was higher among the obese (BMI>=30): 8.3% versus 1.4% (P<.001). A comparison of the mortality rates for obese patients with OSAHS (15%) and obese patients without OSAHS showed similar results (16%) (P=.94). Moreover, most of the patients diagnosed with OSAHS were receiving adequate therapy in the pneumology department, although exact figures have not been recorded. The assumption proposed by Arias et al with regard to the differences in mortality is interesting. As far as we are aware, however, it has not yet been shown that continuous positive airway pressure therapy improves the survival of patients with heart failure and OSAHS, even though ventricular function can be improved in some patients.1-3 Therefore, cannot be affirmed that the difference in mortality in favour of obese persons, would have been even higher if all obese individuals with OSAHS had been diagnosed and actively treated. As Arias et al mentioned, the results of future studies are needed to answer this hypothesis.