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(Chest. 2003;124:942-947.)
© 2003 American College of Chest Physicians

Quality of Life in Bed Partners of Patients With Obstructive Sleep Apnea or Hypopnea After Treatment With Continuous Positive Airway Pressure*

James M. Parish, MD, FCCP and Philip J. Lyng, MD

* From the Division of Pulmonary Medicine, Mayo Clinic, Scottsdale, AZ.

Correspondence to: James M. Parish, MD, FCCP, Division of Pulmonary Medicine, Mayo Clinic, 13400 East Shea Blvd, Scottsdale, AZ 85259


   Abstract
TOP
 Abstract
Introduction
 Materials and Methods
 Results
 Discussion
 References
 
Objective: Obstructive sleep apnea (OSA) has been shown to affect the quality of life (QOL) in patients, and QOL improves after treatment with nasal continuous positive airway pressure (CPAP). However, the effects on the bed partner of the patient with OSA have received little attention. We studied QOL in patients with OSA and their bed partners, and the effect of CPAP therapy on QOL.

Design: Fifty-four patients and their bed partners who had been seen for evaluation of OSA, had undergone polysomnography, and subsequently had received treatment with CPAP. Patients and bed partners completed the Epworth sleepiness scale (ESS) and QOL questionnaires before and after the patients’ therapy.

Setting: Sleep disorders center in an academic medical center.

Participants: Patients with documented OSA and regular bed partners.

Interventions: Both individuals completed the 36-item short-form health survey (SF-36), the ESS, and the Calgary sleep apnea quality of life index (SAQLI). At about 6 weeks after CPAP therapy, patients and their bed partners completed the same set of questionnaires again.

Results: Of the 54 subjects who completed the study, the mean (± SD) apnea-hypopnea index was 48.4 ± 33.3. For the subjects, the mean ESS decreased from 12.9 ± 4.4 to 7.3 ± 4.0 (p < 0.001) after treatment with CPAP. For the bed partners, the mean ESS decreased from 7.4 ± 6.1 to 5.8 ± 4.7 (p = 0.02). The mean scores on the SAQLI were 4.1 ± 1.0 for the subjects and 4.5 ± 1.3 for the bed partners. Following CPAP therapy, the SAQLI increased in the subjects to 4.9 ± 1.2 (p < 0.001), and in the bed partners to 5.1 ± 0.9 (p = 0.002). The SF-36 showed positive changes in both the subjects and the bed partners. Significant improvements were observed in the subjects in role-physical, vitality, social functioning, role-emotional, and mental health domains. In the bed partners, significant changes in the SF-36 were observed in role-physical, vitality, social functioning, and mental health domains.

Conclusion: OSA results in impaired QOL in both the patients and their bed partners. Treatment with CPAP improves QOL, as measured by the SF-36 and the SAQLI.

Key Words: continuous positive airway pressure therapy • Epworth sleepiness scale • obstructive sleep apnea • quality of life • short form 36 • sleep apnea syndromes


   Introduction
TOP
 Abstract
 Introduction
Materials and Methods
 Results
 Discussion
 References
 
Obstructive sleep apnea (OSA) is a common disorder that is characterized by repetitive episodes of upper airway occlusion during sleep that result in oxyhemoglobin desaturation and arousal from sleep. OSA has been associated with several health-related consequences.1 Its estimated prevalence is 2% in women and 4% in men.2

The most common treatment for OSA is continuous positive airway pressure (CPAP), which reverses upper airway occlusion and improves sleep quality, subsequently reducing daytime sleepiness. Several studies3 have shown that quality of life (QOL) is impaired in patients with OSA and that it improves with CPAP treatment. However, few studies have examined the QOL of the bed partners of patients with OSA. Yet, we have found that the spouse or bed partner of an individual with OSA also has disrupted sleep because of the patient’s snoring, gasping, or choking respirations, or because of the bed partner’s own concern about the patient’s breathing pauses or other abnormal breathing. Beninati et al4 have shown that the spouses of patients with OSA also must cope with frequent arousals from sleep. However, how this affects the spouses’ overall QOL or whether they benefit when treatment with CPAP is initiated remains unknown. The purpose of our study was to examine the effects of OSA on QOL in the patient with OSA and on the patient’s bed partner, and subsequently to examine the effects on the QOL of both parties after the patient has been treated with CPAP.


   Materials and Methods
TOP
 Abstract
 Introduction
 Materials and Methods
Results
 Discussion
 References
 
Subject Identification
Subjects for this study were identified from a pool of patients who were evaluated between January 2000 and September 2001 at the Mayo Clinic in Scottsdale, AZ, during a sleep disorders consultation. The study was approved by the Mayo Foundation Institutional Review Board prior to enrolling subjects. Patients who had symptoms of OSA syndrome and an apnea-hypopnea index of > 10 events per hour were asked to participate in the study if they had regular bed partners and if they agreed to treatment with CPAP. To determine the optimal CPAP pressure necessary to eliminate apneas, hypopneas, and snoring, we conducted in-laboratory polysomnography on all patients during either a split-night or a full-night study of attended CPAP titration. Those subjects qualifying for treatment with CPAP then were set up with a CPAP machine by a home health agency shortly after their polysomnogram.

Before patients were treated with CPAP, each patient and the patient’s bed partner who consented to participate in the study were asked to fill out the Epworth sleepiness scale (ESS) questionnaire, the 36-item short form health survey (SF-36), and the Calgary sleep apnea quality of life index (SAQLI). They were then asked to return in 6 weeks for a follow-up visit to complete the same questionnaires again. If a patient was unwilling or unable to return for follow-up, the questionnaires were mailed to the patient and the partner to be filled out with telephone assistance from a study coordinator.

Quality-of-Life Measures
The ESS5 6 is a widely used eight-item questionnaire that measures the subjective sensation of recent sleepiness. Subjects are asked to rate how likely they are to fall asleep, as opposed to just feeling tired, in eight specific quiet or relaxed situations. The scale runs from zero (unlikely to fall asleep in any of the eight relaxed situations) to 24 (high chance of falling asleep in all eight situations).

The SF-36 is a widely used and validated questionnaire that measures QOL in health-related states and conditions.7 This instrument does not contain questions related directly to the effects of sleep disorders but instead has questions that focus on QOL in general rather than in relation to any specific disease. The SF-36 produces a profile of eight dimensions of health status, but the following two summary scores can be extrapolated: a physical component summary; and a mental component summary. The SF-36 has been used in many studies of medical conditions. It also has been used to assess QOL in patients with OSA and, in particular, to measure the effects of CPAP. National norms for SF-36 by age and sex are available for the population of the United States.

The SAQLI is a validated questionnaire that was developed as a QOL instrument specifically for OSA.8 9 It was designed to identify symptoms and impairments of functioning that are sensitive to changes experienced by patients. The SAQLI, which assesses the possibility that treatment for OSA adversely affects QOL, consists of the following five domains: daily functioning (domain A); social interactions (domain B); emotional functioning (domain C); symptoms (domain D); and treatment-related symptoms (domain E).9 The total SAQLI score for domains A through D is obtained before the patient has received treatment with CPAP, and the score for domain E is factored in after the patient has received treatment.

Polysomnography
Polysomnography was performed by monitoring electrooculography, two electroencephalography leads, submental electromyogram, oronasal airflow either by thermocouple or by pressure transducer, respiratory effort by piezo belts, oxyhemoglobin saturation by oximetry, ECG, and anterior tibialis electromyogram.

Compliance with CPAP was monitored in all subjects in the study in two ways. Subjective information was obtained by asking patients at the 6-week follow-up visit how many hours per night they used CPAP. Objective data were obtained by measuring the actual hours of CPAP use from data recorded by a microprocessor in each CPAP blower unit.

Statistical Analysis
In the first analysis, pairwise comparisons between baseline scores and national norms were calculated, and statistical significance was calculated by using the paired t test. In the second analysis, pairwise comparisons between baseline and posttreatment mean scores for ESS, SAQLI (all subcategories), and SF-36 (all subcategories) were calculated for the patients and their bed partners who completed the study. Statistical significance was calculated by using the paired t test. The scores and means of several variables were calculated for both groups of subjects. These then were compared with the scores and means for patients and bed partners who did not complete the study. Statistical significance was calculated by using the t test.


   Results
TOP
 Abstract
 Introduction
 Materials and Methods
 Results
Discussion
 References
 
From the patients who were evaluated for sleep disorders consultations at Mayo Clinic Scottsdale between January 2000 and September 2001, 81 OSA patients and their bed partners were enrolled into the study. Of these 81 pairs, 54 completed the entire study. The data for 27 patients and their bed partners were excluded because these persons were unable or unwilling to return to complete the second part of the study, despite multiple telephone and mail requests by the study coordinator. The most common reason for not completing the study was the patient’s inability to tolerate CPAP or the ability to tolerate it only for minimal periods. Patients who did not complete the study did not differ significantly from patients who did complete both sets of questionnaires. Mean age, ratio of men to women, mean body mass index, mean apnea-hypopnea index, and scores on ESS, SAQLI, and SF-36 did not differ significantly between the two groups.

Of the 54 pairs who completed the study, the mean age of the patients was 58.9 years (SD, 14.1 years), and 47 were men and 7 were women (Table 1 ). The mean age of the bed partners was 56.3 years, and 47 were women and 7 were men. Patients who completed the study had an initial mean (± SD) apnea-hypopnea index of 48.4 ± 33.3 events per hour.


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  		Table 1. Characteristics of Patients in Study Group*

 
All patients who completed the study reported regular nightly use of CPAP. Objective data from microprocessor recordings from the CPAP units were obtained successfully in 48 of the 54 patients who completed the study. Objective compliance monitoring revealed a mean of 6.1 h of CPAP use nightly (range, 1.7 to 9.0 h per night). No patient in the study requested that the CPAP unit be returned to the home health company.

The SF-36 scores of each patient (Table 2 ) and the patient’s bed partner (Table 3 ) were compared with the norms established for the US population, adjusted for age. At baseline, the patients’ reported scores on the QOL domains were significantly lower than the national norms for those domains. Three of the four domains of physical health were significantly lower than the national norms (ie, physical functioning, role-physical, and bodily pain). In the area of mental health, the domains of vitality, social functioning, and role-emotional were all significantly lower than the national norms.


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  		Table 2. Comparison of the Baseline SF-36 Scores of Patients to National Norms*

 

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  		Table 3. Comparison of the Baseline SF-36 Scores of Bed Partners to National Norms*

 
In contrast, in the group of bed partners, the domains of physical functioning, role-physical, general health, vitality, social functioning, role-emotional, and mental health did not differ significantly from US norms. Only in the domain of bodily pain was the bed partners’ score significantly below the expected norm (Table 3) .

The SF-36 scores of both groups were compared before CPAP therapy and after 6 weeks of CPAP therapy (Tables 4 and 5 ). The patients as a group improved significantly after CPAP therapy, although physical functioning, bodily pain, and general health did not change significantly.


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  		Table 4. Change in the Scores of Patients on the ESS and on the SF-36 After Treatment With CPAP*

 

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  		Table 5. Change in the Scores of Bed Partners of Patients on the ESS and the SF-36 After Treatment With CPAP*

 
Bed partners’ baseline scores were compared with their posttreatment scores. There were significant improvements in the domains of role-physical, vitality, social functioning, and mental health. Posttreatment scores in the domains of physical functioning, general health, bodily pain, and role-emotional did not differ significantly from baseline scores.

On the SAQLI (Table 6 ), the mean score for bed partners was 4.5 ± 1.3 before treatment, increasing to 5.1 ± 0.9 after treatment (p = 0.002). Domains A, B, and C increased significantly for the bed partners (p < 0.001 for each domain). Domain D showed a trend toward improvement, but the change was not significant.


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  		Table 6. Change in the Scores of Patients and Their Bed Partners on the SAQLI After Treatment With CPAP*

 

   Discussion
TOP
 Abstract
 Introduction
 Materials and Methods
 Results
 Discussion
References
 
This study was designed to test the hypothesis that OSA affects not only persons with OSA but also their bed partners, resulting in decreased QOL and increased sleepiness for both that improves when patients receive CPAP therapy. We confirmed that patients with OSA have reduced QOL compared with the national norms established for the SF-36, a frequently used measure of QOL in disease states.

In our study, the baseline QOL for bed partners was not significantly different from national norms except in the domain of bodily pain. There is no clear explanation of why the bodily pain domain should be abnormal when the other domains are normal. However, after patients used CPAP, we observed significant increases in QOL scores for bed partners as well as for patients. After CPAP therapy, the patients as a group improved significantly in the domains of role-physical, vitality, social functioning, role-emotional, and mental health. However, their physical functioning, bodily pain, and general health did not change significantly. The bed partners improved significantly in the domains of role-physical, vitality, social functioning, and mental health. Physical functioning, general health, bodily pain, and role-emotional did not differ significantly from baseline in bed partners after the treatment of patients with CPAP. Hence, although baseline QOL was not low, at least in comparison with national norms, there was improvement for the bed partners after patients had received CPAP treatment. The improved QOL seemed to be in accordance with our clinical impression that not only patients but also bed partners improve when OSA is treated effectively.

Our study also showed that ESS scores of the OSA patient and the bed partner improved after effective treatment. Although the ESS is a subjective instrument, and studies10 11 12 have not found strong correlations between it and the multiple sleep latency test, it is a commonly used measure of sleepiness that correlated in at least one study13 with subjective improvement after CPAP therapy. The high mean ESS scores of our patients at baseline decreased significantly after treatment with CPAP. Although the mean ESS scores of bed partners before treatment were within the upper range of normal, the mean ESS score decreased significantly after the patients were treated with CPAP.

We also used a QOL instrument that was specific for sleep disorders, the SAQLI. We found that the mean score on the SAQLI increased for both the patients and the patients’ bed partners. Scores for all four domains increased for the patients, whereas scores for three of the four domains increased for the bed partners. Domain E is related to treatment effects and hence is not applicable because the bed partners did not receive treatment themselves.

One weakness of our study is the fairly high exclusion rate, despite vigorous efforts to obtain follow-up data. However, the baseline data for the group of nonresponders did not differ from the data for the group that finished the study. We believe that the group of nonresponders had more patients who did not comply with CPAP therapy or who could not tolerate CPAP and so "gave up" on the study. If such is the case, it would imply that our study is biased because it primarily included a group of patients who were more likely to comply with CPAP therapy and, thus, may not have been representative of the entire population of OSA patients. However, they would well represent patients who use CPAP regularly to treat OSA. Therefore, our data suggested that patients who use CPAP do indeed benefit from its use.

Other weaknesses of our study are that it is an observational study comparing baseline characteristics with posttreatment characteristics, and it was not randomized or placebo-controlled. Given that CPAP has been shown to be an effective therapy for OSA, we decided that an observational study conducted before treatment and after treatment would not result in a treatment delay for half the patients. In prospective, randomized, blinded studies, CPAP has been shown to be an effective treatment for OSA.14 15

Several investigators have shown that QOL is adversely affected in patients with OSA and that it improves with treatment.16 17 18 19 20 Other studies have examined the effects of OSA on the QOL of bed partners. Beninati et al4 have shown that a patient’s snoring causes increased arousals from sleep in the bed partner that decrease in number when the patient is treated with CPAP. Using the ESS and a nine-item nonvalidated questionnaire about sleep quality, daytime alertness, mood, QOL, and personal relationship, Kiely and McNicholas21 assessed bed partners’ responses to patients’ treatment for OSA after the partner began receiving CPAP therapy and found improvement in all the variables measured. McArdle et al22 showed that a bed partner often reports subjectively poor sleep before the patient is treated with CPAP and that reported sleep quality improves after CPAP treatment, but that objective measures of sleep do not differ between CPAP-treated patients and placebo-treated patients.

Our study was a systematic examination of the generic QOL and the disease-specific QOL of patients with OSA and of their regular bed partners. As expected, we found that QOL, as assessed by the SF-36 and the SAQLI, was impaired in patients with OSA and that it improved with CPAP therapy. Our data also showed that although QOL does not appear to be impaired in the bed partners of patients with OSA, as measured by the SF-36 and the SAQLI, it nevertheless improves significantly when the patient receives CPAP therapy.


   Acknowledgements
 
The authors thank Bernie W. Miller, RRT, Robin N. Cremer, PA-C, Lynda S. Facchiano, FNP, Carolyn J. Barbieri, Teresa E. Radam, and José L. Hernandez for their assistance with this project.


   Footnotes
 
Abbreviations: CPAP = continuous positive airway pressure; ESS = Epworth sleepiness scale; OSA = obstructive sleep apnea; QOL = quality of life; SAQLI = Calgary sleep apnea quality of life index; SF-36 = 36-item short form health survey

Received for publication October 24, 2002. Accepted for publication March 26, 2003.


   References
TOP
 Abstract
 Introduction
 Materials and Methods
 Results
 Discussion
 References
 

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