[Upper airway complaints of patients with obstructive sleep apnea - effect of CPAP]

The most common side effects of nocturnal CPAP treatment are problems affecting the mouth, nose and throat in patients with obstructive sleep apnea syndrome (OSAS). Employing a visual analogue scale, the extent of these complaints in OSAS patients who were investigated for the first time in a sleep laboratory was determined prior to and following the initiation of CPAP treatment. In comparison with a control group, the severity of the subjective complaints of dry nose, dry mouth and throat was significantly greater, even before initiation of CPAP therapy. After the first treatment night, the severity of the side effects increased further throughout the entire group. In a subgroup analysis, it was seen that, in particular, those patients with a low pre-treatment complaints index, or an apnea-hypopnea index (AHI) of less than 20, experienced an increase in these complaints while undergoing treatment, whereas those with a high baseline AHI experienced a decrease in complaints during therapy. We surmise that the reason behind this could be a decrease in oral breathing, in particular in those patients with a high AHI, while patients with a comparatively milder degree of disturbed nocturnal breathing experience more side effects involving the oropharyngeal mucosa. These patients may, perhaps, need greater care with the adjustment and fitting of the CPAP device and mask. However, when the data are interpreted it must not be forgotten that this effect might be a purely statistical phenomenon reflecting regression to the mean. Using the questionnaire described herein, the severity of such complaints can be determined.