Sleep, 15:S42-546 © 1992 American Sleep Disorders Association and Sleep Research Society
Long-Term Compliance With Nasal Continuous Positive Airway Pressure (CPAP) in Obstructive Sleep Apnea Patients and Nonapneic Snorers Jean Krieger Sleep Disorders Unit, University Hospital, Strasbourg, France
Summary: In a prospective study aimed at evaluating objectively the compliance with nasal continuous positive airway pressure (CPAP) treatment, 233 obstructive skep apnea (OSA) (apnea index, > 10 apneas/hour) patients and 36 nonapneic snorers were studied. The compliance to treatment was measured by the mean rate of use of the CPAP device, obtained from a built-in time counter. The follow-up period was 874 ± 48 in OSA patients and 675 ± 83 in snorers. CPAP was proposed to all OSA patients but only to those snorers who felt improved after an initial laboratory night on CPAP. Nineteen OSA patients refused CPAP. Of the 214 OSA patients who accepted CPAP, 181 are still on treatment, with a mean daily rate of use of 5.6 ± 0.1 hours (mean ± SEM); 22 patients stopped CPAP after a variable period of time; 10 patients died and one acromegalic patient was considered cured after hypophysectomy for a pituitary adenoma. Depending upon the definition of acceptable compliance, the compliance rate in this group was between 77% and 89%. The mean rate of use was correlated with indices of disease severity (apnea index, apnea + hypopnea index, minimal Sa02 during sleep, daytime Pa02, pulmonary artery pressure). Thirty-six nonapneic snorers accepted CPAP. In this group, 26 are still on CPAP, with a mean daily rate of use of 5.4 ± 0.5 hours; one patient died; one underwent uvolopalatopharyngoplasty without follow-up; and eight stopped CPAP. The compliance rate in this group was between 58% and 78%. This study shows that CPAP is reasonably accepted by OSA patients as well as by nonapneic snorers. Both within and between groups, disease severity seemed to playa role in the quality of compliance to treatment. Key Words: Obstructive sleep apnea-Continuous positive airway pressure-Snoring-Compliance to treatment.
Nasal continuous positive airway pressure (CPAP) has been shown to eliminate sleep apneas and apnea·· related hypoxemia (1). It also normalizes sleep pat.. tern, reduces intrathoracic pressure swings, stabilizes the heart rate and eliminates pulmonary hypertension peaks (2). Whereas the efficacy and safety of nasal con .. tinuous positive airway pressure (CPAP) are generally acknowledged, its acceptability has been questioned (3), mainly because of the constraints related to the necessity for the patient to wear a nasal mask connected to a pressure generator during sleep. Because the therapeutic success of CPAP relies on patient acceptance of the device, it is of paramount importance to evaluate the actual rate of use of the treatment. Most previous studies evaluating treatment acceptance were based on the patients' own reports (4,5), which are likely to be biased. Studies using an Accepted for publication June 1992. Address correspondence and reprint requests to Dr. Jean Krieger, Clinique Neurologique, University Hospital, F-67091 Strasbourg Cedex, France.
objective measure ofthe daily rate of use ofthe CPAP device included small patient samples (6,7, n = 46 and 20, respectively). Recent data from our group obtained in a prospective study ofa large group of patients with an objective measurement ofthe rate at which the patients use their treatment confirm and extend previously published results showing that nasal CPAP is generally well-accepted (4,6,7). METHODS The population studied comprised two different subgroups, investigated following the standard procedure used in our laboratory (8). Two hundred thirty-three patients had classical obstructive sleep apnea (OSA: apnea index> 10). Nasal CPAP was recommended for all these patients, regardless oftheir age or the severity of their condition, even when they felt that the treatment was inconvenient. The rationale behind this attitude was that the major alternative treatment, i.e.,
S42 Downloaded from https://academic.oup.com/sleep/article-abstract/15/suppl_6/S42/2749335 by guest on 14 March 2018
CPAP COMPLIANCE IN OSA PATIENTS
TABLE 1. Main characteristics and comparisons among the groups studied. A: OSA patients who refused CPAP; B: OSA patients who started CPAP treatment; F: nonapneic snorers. Among the OSA patients who started CPAP: C: patients still on treatment; D: deceased patients; E: patients who stopped treatment. BMI = Body mass index; AI = Apnea index; AHI = Apnea + hypopnea index; Rate = mean rate of use
Age BMI AI AHI Pa0 2 :....
PaC0 2 FEV,
CPAP Rate
I.'0
I
Snorers on CPAP
OSA on CPAP
OSA
I"
I
S43
n = 19 A
n = 214 B
n = 181 C
n = 10 D
E
54 ± 2 (39-65) 31 ± I (23-48) 52 ± 10 (12-189) 71 ± II (17-189) 73 ± 3 (46-92) 38 ± I (330-57) 2.7 ± 0.2 (0.7-3.8)
53 ± I (28-79) 32 ± 0 (19-65) 68 ± 2 (10-179) 82 ± 2 (12-179) 73 ± 1 (41-100) 39 ± 0 (22-54) 2.7 ± 0.1 (0.4-4.5) 9.6 ± 0.2 (3-18) 5.3 ± 0.2 (0.2-10.3)
53 ± I
64 ± 3
52 ± 3
32 ± 0
31 ± I
31 ± 2
69 ± 3
54 ± 10
67 ± 7
83 ± 2
75 ± 9
78 ± 7
73 ± I
65 ± 3
76 ± 2
39 ± 0
42 ± 2
37 ± 1
2.7 ± 0.1
1.9 ± 0.2
2.7 ± 0.2
9.7 ± 0.2
9.5 ± 0.9
9.0 ± 0.5
5.6 ± 0.1
4.4 ± 0.8
2.4 ± 0.6
n = 22
surgery, has a success rate of only about 50% and is not devoid of complications (9). This was clearly explained to the patients, as well as the possibility of an alternative treatment if they found the constraints of CPAP to be unacceptable. Thirty-six patients did not meet classical criteria for OSA (apnea index < 10), but were basically snorers who complained of chronic fatigue and whose recordings evidenced snoring associated with obvious signs of increased airway resistance (a 2- to 4-fold increase in inspiratory esophageal pressure swings as compared to wakefulness, along with a decrease in airflow) and, in some, repeated hypopneas. They were invited to test nasal CPAP for one night in the sleep laboratory. If they felt an improvement after a single treatment night and were willing to continue CPAP at home, they were given the opportunity to participate. The 233 OSA patients and 36 nonapneic snorers will be discussed separately. Nineteen of the 233 OSA patients (8.2%) refused the treatment after the first laboratory night on CPAP. They tended to have less severe OSA than the remaining 214 but were otherwise not significantly different with respect to age, overweight, or daytime Pa0 2 (Table 1). All but one ofthese 19 patients also refused the surgical treatment proposed as an alternative to nasal CPAP. Therefore, they cannot be considered as nonacceptance cases specific to CPAP. Accordingly, the percentage of compliance to treatment was calculated on the basis of the remaining 214 patients. The main characteristics of the 214 (199 males) OSA patients who accepted CPAP treatment as well as of
Unpaired t test
n = 36 F
AlB
CIC
C/E
B/F
52 ± 2 (30-67) 31 ± I (21-59) 5± I (0-10) 31 ± 4 (4-96) 75 ± 2 (50-99) 37 ± 1 (16-52) 2.6 ± 0.1 (1.0-4.2) 6.6 ± 0.3 (3-11) 4.5 ± 0.4
NS
Long-Term Compliance With Nasal Continuous Positive Airway Pressure (CPAP) in Obstructive Sleep Apnea Patients and Nonapneic Snorers Jean Krieger Sleep Disorders Unit, University Hospital, Strasbourg, France
Summary: In a prospective study aimed at evaluating objectively the compliance with nasal continuous positive airway pressure (CPAP) treatment, 233 obstructive skep apnea (OSA) (apnea index, > 10 apneas/hour) patients and 36 nonapneic snorers were studied. The compliance to treatment was measured by the mean rate of use of the CPAP device, obtained from a built-in time counter. The follow-up period was 874 ± 48 in OSA patients and 675 ± 83 in snorers. CPAP was proposed to all OSA patients but only to those snorers who felt improved after an initial laboratory night on CPAP. Nineteen OSA patients refused CPAP. Of the 214 OSA patients who accepted CPAP, 181 are still on treatment, with a mean daily rate of use of 5.6 ± 0.1 hours (mean ± SEM); 22 patients stopped CPAP after a variable period of time; 10 patients died and one acromegalic patient was considered cured after hypophysectomy for a pituitary adenoma. Depending upon the definition of acceptable compliance, the compliance rate in this group was between 77% and 89%. The mean rate of use was correlated with indices of disease severity (apnea index, apnea + hypopnea index, minimal Sa02 during sleep, daytime Pa02, pulmonary artery pressure). Thirty-six nonapneic snorers accepted CPAP. In this group, 26 are still on CPAP, with a mean daily rate of use of 5.4 ± 0.5 hours; one patient died; one underwent uvolopalatopharyngoplasty without follow-up; and eight stopped CPAP. The compliance rate in this group was between 58% and 78%. This study shows that CPAP is reasonably accepted by OSA patients as well as by nonapneic snorers. Both within and between groups, disease severity seemed to playa role in the quality of compliance to treatment. Key Words: Obstructive sleep apnea-Continuous positive airway pressure-Snoring-Compliance to treatment.
Nasal continuous positive airway pressure (CPAP) has been shown to eliminate sleep apneas and apnea·· related hypoxemia (1). It also normalizes sleep pat.. tern, reduces intrathoracic pressure swings, stabilizes the heart rate and eliminates pulmonary hypertension peaks (2). Whereas the efficacy and safety of nasal con .. tinuous positive airway pressure (CPAP) are generally acknowledged, its acceptability has been questioned (3), mainly because of the constraints related to the necessity for the patient to wear a nasal mask connected to a pressure generator during sleep. Because the therapeutic success of CPAP relies on patient acceptance of the device, it is of paramount importance to evaluate the actual rate of use of the treatment. Most previous studies evaluating treatment acceptance were based on the patients' own reports (4,5), which are likely to be biased. Studies using an Accepted for publication June 1992. Address correspondence and reprint requests to Dr. Jean Krieger, Clinique Neurologique, University Hospital, F-67091 Strasbourg Cedex, France.
objective measure ofthe daily rate of use ofthe CPAP device included small patient samples (6,7, n = 46 and 20, respectively). Recent data from our group obtained in a prospective study ofa large group of patients with an objective measurement ofthe rate at which the patients use their treatment confirm and extend previously published results showing that nasal CPAP is generally well-accepted (4,6,7). METHODS The population studied comprised two different subgroups, investigated following the standard procedure used in our laboratory (8). Two hundred thirty-three patients had classical obstructive sleep apnea (OSA: apnea index> 10). Nasal CPAP was recommended for all these patients, regardless oftheir age or the severity of their condition, even when they felt that the treatment was inconvenient. The rationale behind this attitude was that the major alternative treatment, i.e.,
S42 Downloaded from https://academic.oup.com/sleep/article-abstract/15/suppl_6/S42/2749335 by guest on 14 March 2018
CPAP COMPLIANCE IN OSA PATIENTS
TABLE 1. Main characteristics and comparisons among the groups studied. A: OSA patients who refused CPAP; B: OSA patients who started CPAP treatment; F: nonapneic snorers. Among the OSA patients who started CPAP: C: patients still on treatment; D: deceased patients; E: patients who stopped treatment. BMI = Body mass index; AI = Apnea index; AHI = Apnea + hypopnea index; Rate = mean rate of use
Age BMI AI AHI Pa0 2 :....
PaC0 2 FEV,
CPAP Rate
I.'0
I
Snorers on CPAP
OSA on CPAP
OSA
I"
I
S43
n = 19 A
n = 214 B
n = 181 C
n = 10 D
E
54 ± 2 (39-65) 31 ± I (23-48) 52 ± 10 (12-189) 71 ± II (17-189) 73 ± 3 (46-92) 38 ± I (330-57) 2.7 ± 0.2 (0.7-3.8)
53 ± I (28-79) 32 ± 0 (19-65) 68 ± 2 (10-179) 82 ± 2 (12-179) 73 ± 1 (41-100) 39 ± 0 (22-54) 2.7 ± 0.1 (0.4-4.5) 9.6 ± 0.2 (3-18) 5.3 ± 0.2 (0.2-10.3)
53 ± I
64 ± 3
52 ± 3
32 ± 0
31 ± I
31 ± 2
69 ± 3
54 ± 10
67 ± 7
83 ± 2
75 ± 9
78 ± 7
73 ± I
65 ± 3
76 ± 2
39 ± 0
42 ± 2
37 ± 1
2.7 ± 0.1
1.9 ± 0.2
2.7 ± 0.2
9.7 ± 0.2
9.5 ± 0.9
9.0 ± 0.5
5.6 ± 0.1
4.4 ± 0.8
2.4 ± 0.6
n = 22
surgery, has a success rate of only about 50% and is not devoid of complications (9). This was clearly explained to the patients, as well as the possibility of an alternative treatment if they found the constraints of CPAP to be unacceptable. Thirty-six patients did not meet classical criteria for OSA (apnea index < 10), but were basically snorers who complained of chronic fatigue and whose recordings evidenced snoring associated with obvious signs of increased airway resistance (a 2- to 4-fold increase in inspiratory esophageal pressure swings as compared to wakefulness, along with a decrease in airflow) and, in some, repeated hypopneas. They were invited to test nasal CPAP for one night in the sleep laboratory. If they felt an improvement after a single treatment night and were willing to continue CPAP at home, they were given the opportunity to participate. The 233 OSA patients and 36 nonapneic snorers will be discussed separately. Nineteen of the 233 OSA patients (8.2%) refused the treatment after the first laboratory night on CPAP. They tended to have less severe OSA than the remaining 214 but were otherwise not significantly different with respect to age, overweight, or daytime Pa0 2 (Table 1). All but one ofthese 19 patients also refused the surgical treatment proposed as an alternative to nasal CPAP. Therefore, they cannot be considered as nonacceptance cases specific to CPAP. Accordingly, the percentage of compliance to treatment was calculated on the basis of the remaining 214 patients. The main characteristics of the 214 (199 males) OSA patients who accepted CPAP treatment as well as of
Unpaired t test
n = 36 F
AlB
CIC
C/E
B/F
52 ± 2 (30-67) 31 ± I (21-59) 5± I (0-10) 31 ± 4 (4-96) 75 ± 2 (50-99) 37 ± 1 (16-52) 2.6 ± 0.1 (1.0-4.2) 6.6 ± 0.3 (3-11) 4.5 ± 0.4
NS
