Respiration 1999;66:128–135

Nasopharyngeal Symptoms in Patients with Obstructive Sleep Apnea Syndrome

Effect of Nasal CPAP Treatment

Brander P.E.a · Soirinsuo M.b · Lohela P.c
Departments of aPulmonary Medicine, bOtorhinolaryngology, and cRadiology, Kiljava Hospital, Kiljava, Finland
email Corresponding Author


 goto top of outline Key Words

  • Nasal CPAP therapy
  • Nasal symptoms
  • Side effects
  • Sleep apnea

 goto top of outline Abstract

Background: Nasal side effects are often reported during nasal continuous positive airway pressure (CPAP) treatment of obstructive sleep apnea syndrome (OSAS) and may make the use of nasal CPAP difficult. Objective: The aim of this study was to evaluate the effect of nasal CPAP on nasopharyngeal symptoms in OSAS patients. Methods: The frequency and severity of nasopharyngeal symptoms and signs were prospectively evaluated in 49 consecutive OSAS patients (37 men, 12 women, mean (SD) age 54 (7) years, body mass index 35 (6) kg/m2) immediately before and after 6 months’ treatment with nasal CPAP. Results: Nasopharyngeal symptoms were common already before starting nasal CPAP: 74% of patients reported dryness, 53% sneezing, 51% mucus in the throat, 45% blocked nose, and 37% rhinorrhea. During nasal CPAP treatment, severity and frequency of sneezing (75%) and rhinorrhea (57%) increased. This increase was related to the season when nasal CPAP was applied, and was more profound in winter than in summer. Mild abnormalities on rhinoscopy and paranasal sinus X-rays were common both at baseline and at follow-up with no significant change during treatment. Conclusions: Nasopharyngeal problems were found to be frequent in patients with OSAS before nasal CPAP treatment, and tended to increase during the treatment.

goto top of outline introduction

Nasal continuous positive airway pressure (CPAP) is the treatment of choice for obstructive sleep apnea syndrome (OSAS) [1]. It has been shown to effectively eliminate sleep apneas and hypopneas and to improve daytime symptoms of OSAS [2, 3, 4]. Side effects have mostly been related to local irritation caused by the nasal mask and by mouth leaks causing high unidirectional nasal airflows [5, 6]. These side effects may cause substantial discomfort to the patients, and may even lead to cessation of the treatment despite improvement of sleep apnea symptoms as such. Serious side effects such as massive epistaxis [7], meningitis [8] and pneumocephalus [9] are rare.

Nasal obstruction increases the tendency to upper airways obstruction during sleep and thus favors the occurrence of snoring and sleep apneas [10]. Nasal obstruction and other nasal disorders often exist in snorers and OSAS patients already before any treatment [11, 12], and possibly increase the susceptibility to nasal side effects during nasal CPAP treatment.

The aim of the present prospective follow-up study was to evaluate nasopharyngeal symptoms, and findings on nasal examination and paranasal sinus X-rays in patients with OSAS both before and after 6 months’ treatment with nasal CPAP.


goto top of outline patients and methods

goto top of outline patients

Fifty-two consecutive OSAS patients starting nasal CPAP treatment were included in the study. All patients underwent a diagnostic limited overnight polygraphic study including simultaneous monitoring of oronasal airflow (thermistors), body and respiratory movements (Static Charge Sensitive Bed, SCSB, Bio-matt, Biorec Inc., Finland), body position and transcutaneous arterial oxygen saturation (SaO2) (pulse oximeter, Biox 3700 Ohmeda, Colo., USA), which was analyzed as described previously [13]. Nasal CPAP treatment was started if the patients had subjective symptoms of OSAS, and the polygraphic recording showed oxygen desaturation index (ODI4), i.e. oxygen desaturation events >4% associated with periodic apneas and hypopneas more than 10/h of time in bed, and the patients agreed to start the treatment. Patients received education about nasal CPAP treatment and practical demonstration of the CPAP equipment, and underwent a mask fitting session during the daytime before the CPAP titration. The pressure of the CPAP device was adjusted during two nights in hospital using overnight oximetry; the minimum pressure level sufficient to prevent oxygen desaturations and normalize nocturnal SaO2 trace in all positions was chosen for the final pressure. Three patients refused to commence home CPAP treatment after the in-hospital trial, and were excluded from further analysis. All patients gave their informed consent. The study was approved by the local ethics committee.

goto top of outline study design

The study was a prospective follow-up study. Nasopharyngeal symptoms and findings on nasopharyngeal examination were evaluated both immediately (the day) before starting nasal CPAP treatment and 6 months later by the same otorhinolaryngologist (M.S.), using a standard questionnaire designed for rhinologic studies. Paranasal sinus X-rays were taken during both visits, checked by another clinician for findings requiring immediate treatment, and then interpreted later blindly by an independent radiologist. If the patients wanted to give up nasal CPAP treatment earlier, the follow-up evaluation was performed after the treatment cessation.

goto top of outline nasopharyngeal examinations

Nasopharyngeal examination consisted of a careful evaluation of nasopharyngeal history, current symptoms, physical examination of nose by rhinoscopy and paranasal sinus X-rays. The patients were asked about following symptoms: recurrent nose bleeding, nasal stuffiness, rhinorrhea, sneezing, feeling of mucus in the throat, dryness of nose, mouth and throat, and blocked ears. In rhinoscopy, nasal mucosal congestion, the color of nasal turbinates and nasal mucosa, nasal crusting, septum deviation, nasal secretion, polyposis and postnasal drip were noted. The use of nasal medication was recorded. Both nasopharyngeal symptoms and findings were scored either using two categories (no abnormality or symptom/abnormal finding present) or a scale from 0 to 3 where 0 denoted no symptom or normal finding and 3 denoted severe symptom/severe abnormality. Mucosal thickening of paranasal sinuses and nasal passages, opacification of paranasal sinuses, fluid levels and paranasal cysts and polyps were looked for in paranasal sinus X-rays.

goto top of outline cpap compliance

Compliance with nasal CPAP treatment was checked both by recording the run time of the nasal CPAP device and by asking the patients how many nights per week they used their CPAP. The mean rate of use (h/day and nights/week) was calculated. Patients were asked whether they have experienced subjective benefit from the treatment. If the patients no longer used nasal CPAP at the time of follow-up, the time and main reason for the treatment cessation were recorded.

goto top of outline statistical analysis

The significance of differences in individual symptoms and findings at baseline and at follow-up were tested by McNemar’s test (frequency analysis) and Wilcoxon signed rank test (symptom scores). Correlations between patient characteristic variables, CPAP pressure and run time, and nasopharyngeal symptoms and findings at follow-up were analyzed by Spearman’s rank test. Unpaired t test, Mann-Whitney U statistics and =χ2 test were conducted to compare differences between separate patient groups.


goto top of outline results

Patient characteristics are shown in table 1. Sixteen patients were current smokers with a mean of (range) 29 (3–70) packyears of smoking, 19 were exsmokers with 24 (1–65) packyears and 14 were never-smokers. There was no change in smoking habits during the study. Two of the 49 patients studied at baseline (both discontinuing the treatment during the first month) did not attend the follow-up examination. Four different types of CPAP machines were used: Sleep Easy III (n = 6) or Rem Star (n = 1) (Respironics Inc, Murraysville, Colo., USA); Rem plus (n = 6) (Stafem, Nancy-Cedex, France), and Tranquility plus (n = 36) (Healthdyne, Marietta, Ga., USA). The patients used silicone nasal masks from Respironics, Sefam, and Healthdyne (Soft Series) or Nasal Seal devices from Healthdyne.


Table 1. Patient characteristics

goto top of outline nasopharyngeal history and symptoms

Sixteen (33%) patients reported a history of chronic rhinitis, 2 of them were on intranasal steroid treatment. Twenty (41%) patients had had at least one paranasal sinus infection before nasal CPAP treatment.

Nasal symptoms were common already before starting nasal CPAP treatment. Dry nose, mouth or throat, sneezing and feeling of mucus in the throat were reported by more than half of the patients (fig. 1). There was an overall increase in the frequency of most of the symptoms during nasal CPAP treatment. A significant increase was observed in the frequency of rhinorrhea and sneezing (p = 0.013) (fig. 1). These symptoms showed also a significant increase in the severity (table 2).


Fig. 1. Prevalence of nasopharyngeal symptoms in all patients at baseline (before starting nasal CPAP) and at follow-up.


Table 2. Nasopharyngeal symptom scores (mean (SD)) at baseline (before starting nasal CPAP) and at follow-up

Twelve patients (24%) gave up nasal CPAP treatment during the 6 months’ study period, 7 of them because of disturbing nasopharyngeal symptoms (table 3). The increase in nasopharyngeal symptoms during nasal CPAP was similar when only those 37 patients who were still using nasal CPAP at follow-up were included in the analysis.


Table 3. Details of the 12 patients who discontinued nasal CPAP treatment during the study (nonusers)

To further examine the change in nasopharyngeal symptoms during nasal CPAP treatment, the patients still using nasal CPAP were divided into two groups according to the season when they had been on nasal CPAP treatment. Group 1 (21 patients) started the treatment during the warmer season (between May and October) and had the follow-up 6 months later, between November and April. Group 2 (16 patients) started nasal CPAP during the cold season (between November and April) and had the follow-up between May and October. A significant increase in the symptom scores for rhinorrhea and sneezing during the treatment was seen in group 1 patients but this was only a trend in group 2 (p = 0.11–0.18) (fig. 2).


Fig. 2. Severity of rhinorrhea and sneezing before (baseline) and after 6 months (follow-up) treatment with nasal CPAP. Only patients (n = 37) still using CPAP at follow-up were included. Group 1 = Patients starting treatment in summer (May–October) and having follow-up in winter; group 2 = patients starting treatment in winter (November–April) and having follow-up in summer.

CPAP pressure was not correlated with the severity of nasal symptoms at follow-up. There were no significant differences in nasopharyngeal symptoms at follow-up between patients using nasal CPAP with a pressure above the median pressure of 10 cm H2O and patients with a pressure of 10 cm H2O or lower. The sum of symptom scores at follow-up was 6.2 (2.8) (pressure >10 cm H2O) and 5.6 (3.3) (pressure <10 cm H2O, p > 0.05), respectively. The type of nasal CPAP device did not effect the development of nasopharyngeal symptoms or treatment continuation.

Nine patients (19%) used regularly either intranasal ipratropium bromide (4 patients) or steroid (beclomethasone or fluticasone, 5 patients) for long-term treatment of nasal symptoms during nasal CPAP. Two of them used intranasal saline and decongestants for temporal relief. Four uncomplicated cases (8%) of acute paranasal sinusitis were observed during the study period.

goto top of outline rhinoscopy and paranasal sinus x-ray findings

Abnormal findings in rhinoscopy were common before nasal CPAP. There were no significant changes either in the frequency (fig. 3) or in the severity of the findings during the study.


Fig. 3. Prevalence of findings innasopharyngeal examination at baseline (before nasal CPAP) and at follow-up.

Swelling of nasal turbinates was a common finding in paranasal sinus X-rays both at baseline (in 71% of patients) and at follow-up (76%). Twenty percent of patients showed radiologic abnormalities in paranasal sinuses both at baseline and at follow-up, the most common finding being mild mucosal congestion of the paranasal sinuses. No significant changes occurred during the study period.

goto top of outline use of nasal cpap treatment

The mean (range) run time of nasal CPAP was 4.0 (1.0–8.1) h/day and the mean reported use of CPAP was 6 (1–7) nights/week. Twelve patients quit nasal CPAP during the study (non-users) (table 3). Eight of them started their treatment in summer, and 4 in winter (NS). All patients in the latter group reported nasopharyngeal problems as the main cause for treatment cessation.

No significant differences were observed between users (i.e. those wo were still using nasal CPAP at follow-up) and nonusers as regards patient characteristics, severity of sleep apnea, CPAP pressure or nasal history. Before nasal CPAP treatment, the symptom score for feeling of mucus in the throat was higher (1.0 vs. 0.5, p < 0.05) in those patients who later discontinued the treatment (fig. 4). At follow-up, dry nose was more common in users (78%) than in nonusers (40%) (p < 0.05). There was a significant difference in the perception of overall treatment benefit obtained from nasal CPAP treatment: 97% of those who were still on nasal CPAP but only 50% of those who have quit the treatment regarded nasal CPAP as beneficial (p < 0.001).


Fig. 4. Severity of nasopharyngeal symptoms (symptom scores 0–3) at baseline in the 12 nonusers (i.e. the patients who discontinued nasal CPAP during the study period) and users (n = 37).


goto top of outline discussion

This study showed that nasopharnygeal symptoms were common in sleep apnea patients before nasal CPAP treatment was started, but that there was an increase in most of these symptoms during 6 months’ treatment. The most profound increase occurred in sneezing and rhinorrhea. This increase seemed to be related to the season when nasal CPAP was used. Severe side effects were not observed. The level of CPAP pressure was not related to nasal side effects. Mild abnormalities in rhinoscopy and paranasal sinus X-ray findings were also common before nasal CPAP treatment, showing no significant changes during the treatment.

Previously, nasal side effects have been reported to occur in 15–65% of patients during nasal CPAP treatment, nasal stuffiness, rhinorrhea and nasal and pharyngeal mucosal drying being the most common symptoms [5, 6, 14, 15, 16]. The frequency of most of the nasopharyngeal symptoms during nasal CPAP treatment was higher in our patients than in previous reports. This may be explained by our prospective study design, the detailed evaluation of the symptoms performed by the investigator during a clinical examination, and the use of symptom scores. In the frequency of symptoms, also mild symptoms (score ≥1) were noted. When only moderate-to-severe symptoms of findings (scores 2–3) were taken into account, the frequency figures were lower and consistent with previous reports. However, a significant increase in the frequency or rhinorrhea and sneezing was observed also with the higher scores.

There may have been several reasons for the discrepancy between increasing rhinorrhea and sneezing, and the rhinoscopy and paranasal sinus X-ray findings which showed no change during nasal CPAP treatment. The patients were asked whether they had experienced symptoms during nasal CPAP treatment, whereas findings on rhinoscopy and X-rays were related to the day of examination. Rhinorrhea and recurrent sneezing were usually most troublesome in the morning immediately after the nasal CPAP use, and often had already subsided when the physical and radiologic investigations were performed later during the day. In addition, most of the patients had mild symptoms (mean symptom scores for rhinorrhea and sneezing during nasal CPAP 1.0 and 1.3). Rhinoscopy and paranasal sinus X-rays could be too insensitive methods to detect changes associated with such mild symptoms, and it also might take more than 6 months of nasal CPAP treatment before permanent mucosal changes could be seen.

One reason for the relative high frequency of nasal problems found in this study may be our nordic climate. Nasal complaints such as rhinorrhea are relatively common in Nordic populations [17]. Dry indoor air during the long cold season might increase nasopharyngeal problems especially during the winter. We tried to analyze this further and separated the patients according to the season when they were on nasal CPAP treatment (group 1 starting treatment between May and October and group 2 starting treatment between November and April). The number of patients in both groups was roughly similar. There were no differences between the two groups either at baseline or at follow-up. However, with respect to change in symptoms during nasal CPAP, the increase in rhinorrhea and sneezing was significant only in patients who had their follow-up examinations during the cold season (group 1). Nasopharyngeal problems were the cause for treatment cessation more often in winter than in summer. These findings suggest that nasal side effects of CPAP may be most troublesome during the winter. As we did not have a control group of sleep apnea patients not using nasal CPAP, we do not know what is the effect of the season alone on nasopharyngeal symptoms. However, when we similarly followed up nasopharyngeal symptoms in a group of snorers (younger and less obese than the sleep apnea patients in the present study) who underwent upper airway surgery [18], no seasonal effect was observed.

Blocked nose has been one of the most common complaints during nasal CPAP treatment [5, 6, 14, 15, 16]. In normal subjects, short-term application of nasal CPAP has been shown to increase mucosal blood flux and nasal resistance during mouth breathing but not during nasal breathing [19, 20]. As far as we know, there are no studies reporting the effect of long-term nasal CPAP treatment on nasal resistance in OSAS patients. In this study nasal resistance or nasal mucosal blood flux was not measured. Nose blockage was evaluated by symptoms, rhinoscopy and by paranasal sinus X-rays. These indirect measurements showed that nasal stuffiness was a common symptom and nasal mucosal congestion was a common finding both in rhinoscopy and in paranasal sinus X-rays already at baseline and that there was no significant increase after 6 months’ treatment with nasal CPAP. Nasal stuffiness was reported as the main cause for treatment cessation by 3 patients who all quit their treatment during the first week. This might suggest that nasal stuffiness is more problematic at the beginning of the treatment.

The level of compliance in terms of the run time of the nasal CPAP was similar to that in most published studies (mean run time 4 h/day) [3, 4, 21, 22, 23]. There was no relationship between the frequency or severity of nasopharyngeal problems either before or during nasal CPAP treatment, and the subjective (nights/week) or objective (run time) CPAP usage. Nasal side effects did affect CPAP compliance in terms of treatment continuation. Slightly more than half of the 12 nonusers (i.e. patients who gave up the treatment), that is 14% of patients who originally started CPAP, reported disturbing nasopharyngeal side effects as the major cause for treatment cessation. As regards long-term continuation of this kind of relatively cumbersome treatment as nasal CPAP, the subjective response to the treatment probably plays a critial role. As observed also previously, lack of subjective improvement seemed to be the only factor which was different between nonusers and users [14]. Fifty percent of the patients who perceived no subjective benefit of the treatment also quit the treatment.

Various kinds of treatments have been used for management of nasal side effects of nasal CPAP treatment. Some patients may benefit from local medication (intranasal saline, decongestants, steroids and anticholinergics) or corrective surgery for obstructive lesions (deviated septum, polyps) [6]. Mouth leaks during application of nasal CPAP have been shown to play a major role in the development of nasal symptoms. During mouth leaks there are high unidirectional airflows which increase nasal mucosal blood flux and disrupt the normal physiologic humidification mechanisms of nasal mucosa and lead to nasal drying, mucosal congestion and increased nasal secretions. Recent studies suggest that the effects of mouth leak on nasal mucosal blood flux and nasal resistance during nasal CPAP can be prevented by fully humidifying the inspired air [19, 20]. Adding a humidification system to the CPAP circuit is probably the most effective way to prevent and treat nasal problems during nasal CPAP treatment [5, 6]. During the present study, external humidifiers were not available to our patients. Local medication – although prescribed to most of the patients – was used to relieve the symptoms only by a few (19%) patients with no obvious success. The frequency of nasal symptoms was similar at follow-up whether the patient was on regular local medication or not. Further research is needed to evaluate whether more active treatment of pre-existing nasal disorders before starting nasal CPAP, and more effective treatment of nasal side effects during nasal CPAP would improve treatment success and compliance rates.

Acute or recurrent sinus or ear infections are relative contraindications of nasal CPAP treatment [2, 5]. Increased pressure in the paranasal sinuses may reduce mucosal drainage and thus predispose to sinus problems. Bacterial meningitis has occurred as a complication of acute paranasal sinus infection during nasal CPAP treatment [8]. We have previously observed several recurrent and prolonged cases of paranasal sinusitis during nasal CPAP treatment especially in patients with preexisting nasal problems (polyposis, chronic rhinitis). Therefore, one specific aim of this study was to prospectively evaluate the incidence of acute sinusitis during nasal CPAP treatment. Four cases (8%) of uncomplicated sinusitis occurred during the 6 months’ treatment period. This is more than in a large retrospective French study, in which during a much longer time period (8 years) the incidence of acute sinusitis was similar [15]. In paranasal sinus X-rays, the frequency of abnormal findings in paranasal sinuses was relatively high but similar both before and during nasal CPAP treatment. However, in patients using nasal CPAP who complain of prolonged respiratory tract infections, the possibility of paranasal sinusitis should be kept in mind.

In conclusion, nasopharyngeal problems were shown to be frequent in patients with OSAS both before and during nasal CPAP treatment. Rhinorrhea and sneezing increased significantly during nasal CPAP. This increase seemed to be related to the season when CPAP was applied. In a few patients nasopharyngeal problems led to treatment cessation.


goto top of outline acknowledgement

We wish to thank Prof. N.J. Douglas for critical review of the manuscript.

 goto top of outline References
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 goto top of outline Author Contacts

Dr. Pirkko E. Brander
Hyvinkää District Hospital
Sairaalakatu 1
FIN–05850 Hyvinkää (Finland)
Fax 358 19 45872407

 goto top of outline Article Information

Received: Received: May 4, 1998
Accepted after revision: September 2, 1998
Number of Print Pages : 8
Number of Figures : 4, Number of Tables : 3, Number of References : 23

 goto top of outline Publication Details

Respiration (International Review of Thoracic Diseases)
Founded 1944 as ‘Schweizerische Zeitschrift für Tuberkulose und Pneumonologie’ by E. Bachmann, M. Gilbert, F. Häberlin, W. Löffler, P. Steiner and E. Uehlinger, continued 1962–1967 as ‘Medicina Thoracalis’

Vol. 66, No. 2, Year 1999 (Cover Date: March-April 1999)

Journal Editor: C.T. Bolliger, Basel; H. Zerzog, Basel
ISSN: 0025–7931 (print), 1423–0356 (Online)

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