Original Article
Quality of life impairment in patients of obstructive sleep apnea and its relation with the severity of disease Naveen Dutt, Ashok Kumar Janmeja1, Prasanta Raghab Mohapatra2, Anup Kumar Singh3 Department of Pulmonary Medicine, All India Institute of Medical Sciences (AIIMS), Jodhpur, Rajasthan, 1Department of Pulmonary Medicine, Government Medical College and Hospital, Chandigarh, 2All India Institute of Medical Sciences (AIIMS), Bhubeneswar, Orissa, India, 3Department of Internal Medicine, Unity Hospital, Rochester, New York, USA
ABSTRACT Background: Several studies have demonstrated considerable impairment of quality of life (QOL) in obstructive sleep apnea (OSA) patients, but its relation with severity of OSA is yet unclear. Study Objectives: To investigate the effects of OSA on the QOL and its association with the disease severity. Design and Setting: Observational, prospective case-control study. Materials and Methods: QOL of 69 OSA patients and 41 healthy controls were assessed using the Calgary sleep apnea quality of life index (SAQLI) on the morning following the polysomnography (PSG) study. Statistics: All statistical analyses were performed using the SPSS 17.0 (SPSS Inc., Chicago). Differences between sleep-related symptoms and SAQLI subscales scores were assessed with the Chi-square test and the Student t-test. Due to non-normal distribution, differences between SAQLI scores of controls and OSA patients were evaluated using a nonparametric Mann-Whitney test. Spearman correlation and backward multiple regression analysis were used to analyze the association between SAQLI scores and sleep indices and anthropometric variables and PSG variables. Results: Study included 69 cases (57 male and 12 females) with a mean age, weight, height, neck circumference, and body mass index 48.45 ± 10.12 years, 83.03 ± 16.48 kg, 159.75 ± 28.29 cm, 44.01 ± 3.23 cm and 30.77 ± 6.71 kg/m2. Mean apnea-hypopnea index was 26.39 ± 16.62. The median score of four SAQLI domains daily function, social interaction, emotional, symptoms and total mean SAQLI score were 3.64 (3.46-3.90), 3.77 (3.51-3.88), 3.64 (3.53-3.83), 4.80 (4.68-5.11), 4.09 (3.88-4.09) ,and 1.36 (1.29-1.71), 1.38 (1.24-1.62), 1.45 (1.23-1.62), 2.00 (1.78-2.26), 1.55 (1.46-1.73) for patients and controls respectively. All the individual domain scores and the mean SAQLI scores of patients were significantly higher than the controls. Conclusion: OSA causes significant impairment of QOL, but the severity of impairment is not directly proportional to the severity of OSA. KEY WORDS: Apnea, obstructive sleep, quality of life, sleep apnea quality of life index Address for correspondence: Dr. Naveen Dutt, Assistant Professor, Department of Pulmonary Medicine, All India Institute of Medical Sciences (AIIMS), Jodhpur, Rajasthan, India. E-mail: [email protected]
INTRODUCTION Obstructive sleep apnea (OSA) is characterized by the occurrence of daytime sleepiness, loud snoring, witnessed breathing interruptions, or awakenings due to gasping or choking in the presence of at least five obstructive Access this article online Quick Response Code:
Website: www.lungindia.com DOI: 10.4103/0970-2113.120603
respiratory events (apneas, hypopneas or respiratory effort related arousals) per hour of sleep. The presence of 15 or more obstructive respiratory events per hour of sleep in the absence of sleep related symptoms is also sufficient for the diagnosis of OSA due to the greater association of this severity of obstruction with important consequences such as increased cardiovascular disease risk. The combination of sleep-disordered breathing with daytime sleepiness is referred to as the OSA syndrome.[1] Prevalence surveys have estimated that about 4% of the middle-aged men and 2% of the middle-aged women are afflicted by OSA in developed countries.[2] Indian prevalence studies estimated disease prevalence rates of 3.5-13.7% (4.4-19.5% in males and 2.5-7.4% in females). Prevalence of OSAS in India is 1.7-3.6% (2.4-7.5% in males and 1-2.1% in females).[3-6]
Lung India • Vol 30 • Issue 4 • Oct ‑ Dec 2013 289
Dutt, et al.: Quality of life impairment in patients of obstructive sleep apnea
The daytime sleepiness is the most common manifestation of OSA. However, other common daytime effects include irritability, decreased concentration, memory impairment, decreased energy and depressive symptoms.[7] Nocturnal symptoms include, restlessness, diaphoresis, awakenings with a sensation of choking or dyspnea, esophageal reflux, heartburn, laryngospasm, frequent nocturia, dry mouth etc. The most catastrophic result of excessive daytime sleepiness (EDS) is falling asleep behind the wheel and causing fatal automobile accidents.[8] Many studies have indicated an association between sleep apnea and cardiovascular/cerebrovascular related morbidity and mortality. It has been associated with the hypertension, coronary artery disease, congestive heart failure, arrhythmias and stroke.[9-13] It has also been associated with an increased mortality.[14] Recently, the studies have confirmed that the impact of OSA on patient’s quality of life (QOL) is rather more widespread than EDS, increased risk of cerebrovascular/ cardiovascular events and other common features mentioned above. Certainly, there are many other domains of life, which remain unexplored in the sleep laboratory. In such cases, Flemons and Reimer and Lacasse et al. have outlined 4 such key domains of health related quality of life (HRQoL) viz. somatic sensation, physical function, emotional state, and social interaction.[15] As the measurements of physiological parameters alone cannot be taken surrogate markers of HRQoL, this emphasizes the need to measure QOL directly.[16] Diverse self-reported instruments have been used to assess resulting impairment like medical outcomes study survey, Short-form 36 health survey Questionnaire (SF-36), Satisfaction with Life Scale, Nottingham Health Profile, General health questionnaire-28. [17-21] These HRQoL instruments have multiple subclasses, each signifying different domains of life. Question mark on the ability of generic questionnaire to detect subtle effects of disease on QOL and effects on QOL brought about by various treatment modalities led to the development of disease specific questionnaire for OSA like Calgary sleep apnea quality of life index (SAQLI), functional outcome of sleepiness questionnaire (FOSQ), and OSA Patient-Oriented Severity Index.[22-24] These disease specific questionnaires have been compared with generic questionnaire. In a study, SAQLI was more responsive to changes in QOL in patients receiving OSA specific treatment than SF-36 and has strong content and constructive validity, but has to be administered by an interviewer.[16] These OSA specific questionnaires are being used increasingly in the newer studies and gradually replacing the generic scales. [25] A comparative study between these disease specific questionnaires have found SAQLI more sensitive than FOSQ.[26] We undertook this study to investigate the overall effect of OSA on human life and where does it affect so that a 290
complete therapy can be planned addressing the specific needs of the patient. Any treatment modality chosen on the basis of derangements in the physiological parameters only is unlikely to be complete as these parameters may not be the true representative of the extent of sufferings of the OSA patients. Thus, there is a need for a complete holistic treatment considering physiological, emotional, and social impairment of the individual patient. The HRQoL has cross-cultural and regional differences even in same clinical condition.[27] Thus, the conclusions drawn from researches done outside India cannot be used to gauge QOL impairment in Indian OSA patients. This study was the need of the hour as there has not been any such study in India.
MATERIALS AND METHODS The present study was conducted over a period of 18 months between March 2006 and August 2007, in an urban population in a North Indian City. The study was conducted after due approval from Ethics Committee of the Institute. During the 1.5 year period consecutive adult patients of either sex who had been referred for snoring, EDS, multiple sleep awakenings were screened with Berlin Questionnaire. Those scored as high-risk cases were subjected to overnight Polysomnography (PSG) following clinical and lab evaluation. Patients with an apnea/ hypopnea index ≥15 or ≥5 with symptoms of OSA were labeled as OSA cases. Those diagnosed as a case of OSA had their QOL assessed by SAQLI questionnaire. The original English version of the questionnaire developed by Flemons and Reimer was translated to the vernacular language of the patients.[22] The translated questionnaire was administered to each patient by the investigator, and the QOL was assessed by the ultimate score obtained by the patient. Subjects who had experienced chronic psychiatric disorders, alcoholism, drug abuse, psychotropic drug abuse, unstable medical disorder, other sleep disorder were excluded. Similarly, severe respiratory disease (FEV1
Quality of life impairment in patients of obstructive sleep apnea and its relation with the severity of disease Naveen Dutt, Ashok Kumar Janmeja1, Prasanta Raghab Mohapatra2, Anup Kumar Singh3 Department of Pulmonary Medicine, All India Institute of Medical Sciences (AIIMS), Jodhpur, Rajasthan, 1Department of Pulmonary Medicine, Government Medical College and Hospital, Chandigarh, 2All India Institute of Medical Sciences (AIIMS), Bhubeneswar, Orissa, India, 3Department of Internal Medicine, Unity Hospital, Rochester, New York, USA
ABSTRACT Background: Several studies have demonstrated considerable impairment of quality of life (QOL) in obstructive sleep apnea (OSA) patients, but its relation with severity of OSA is yet unclear. Study Objectives: To investigate the effects of OSA on the QOL and its association with the disease severity. Design and Setting: Observational, prospective case-control study. Materials and Methods: QOL of 69 OSA patients and 41 healthy controls were assessed using the Calgary sleep apnea quality of life index (SAQLI) on the morning following the polysomnography (PSG) study. Statistics: All statistical analyses were performed using the SPSS 17.0 (SPSS Inc., Chicago). Differences between sleep-related symptoms and SAQLI subscales scores were assessed with the Chi-square test and the Student t-test. Due to non-normal distribution, differences between SAQLI scores of controls and OSA patients were evaluated using a nonparametric Mann-Whitney test. Spearman correlation and backward multiple regression analysis were used to analyze the association between SAQLI scores and sleep indices and anthropometric variables and PSG variables. Results: Study included 69 cases (57 male and 12 females) with a mean age, weight, height, neck circumference, and body mass index 48.45 ± 10.12 years, 83.03 ± 16.48 kg, 159.75 ± 28.29 cm, 44.01 ± 3.23 cm and 30.77 ± 6.71 kg/m2. Mean apnea-hypopnea index was 26.39 ± 16.62. The median score of four SAQLI domains daily function, social interaction, emotional, symptoms and total mean SAQLI score were 3.64 (3.46-3.90), 3.77 (3.51-3.88), 3.64 (3.53-3.83), 4.80 (4.68-5.11), 4.09 (3.88-4.09) ,and 1.36 (1.29-1.71), 1.38 (1.24-1.62), 1.45 (1.23-1.62), 2.00 (1.78-2.26), 1.55 (1.46-1.73) for patients and controls respectively. All the individual domain scores and the mean SAQLI scores of patients were significantly higher than the controls. Conclusion: OSA causes significant impairment of QOL, but the severity of impairment is not directly proportional to the severity of OSA. KEY WORDS: Apnea, obstructive sleep, quality of life, sleep apnea quality of life index Address for correspondence: Dr. Naveen Dutt, Assistant Professor, Department of Pulmonary Medicine, All India Institute of Medical Sciences (AIIMS), Jodhpur, Rajasthan, India. E-mail: [email protected]
INTRODUCTION Obstructive sleep apnea (OSA) is characterized by the occurrence of daytime sleepiness, loud snoring, witnessed breathing interruptions, or awakenings due to gasping or choking in the presence of at least five obstructive Access this article online Quick Response Code:
Website: www.lungindia.com DOI: 10.4103/0970-2113.120603
respiratory events (apneas, hypopneas or respiratory effort related arousals) per hour of sleep. The presence of 15 or more obstructive respiratory events per hour of sleep in the absence of sleep related symptoms is also sufficient for the diagnosis of OSA due to the greater association of this severity of obstruction with important consequences such as increased cardiovascular disease risk. The combination of sleep-disordered breathing with daytime sleepiness is referred to as the OSA syndrome.[1] Prevalence surveys have estimated that about 4% of the middle-aged men and 2% of the middle-aged women are afflicted by OSA in developed countries.[2] Indian prevalence studies estimated disease prevalence rates of 3.5-13.7% (4.4-19.5% in males and 2.5-7.4% in females). Prevalence of OSAS in India is 1.7-3.6% (2.4-7.5% in males and 1-2.1% in females).[3-6]
Lung India • Vol 30 • Issue 4 • Oct ‑ Dec 2013 289
Dutt, et al.: Quality of life impairment in patients of obstructive sleep apnea
The daytime sleepiness is the most common manifestation of OSA. However, other common daytime effects include irritability, decreased concentration, memory impairment, decreased energy and depressive symptoms.[7] Nocturnal symptoms include, restlessness, diaphoresis, awakenings with a sensation of choking or dyspnea, esophageal reflux, heartburn, laryngospasm, frequent nocturia, dry mouth etc. The most catastrophic result of excessive daytime sleepiness (EDS) is falling asleep behind the wheel and causing fatal automobile accidents.[8] Many studies have indicated an association between sleep apnea and cardiovascular/cerebrovascular related morbidity and mortality. It has been associated with the hypertension, coronary artery disease, congestive heart failure, arrhythmias and stroke.[9-13] It has also been associated with an increased mortality.[14] Recently, the studies have confirmed that the impact of OSA on patient’s quality of life (QOL) is rather more widespread than EDS, increased risk of cerebrovascular/ cardiovascular events and other common features mentioned above. Certainly, there are many other domains of life, which remain unexplored in the sleep laboratory. In such cases, Flemons and Reimer and Lacasse et al. have outlined 4 such key domains of health related quality of life (HRQoL) viz. somatic sensation, physical function, emotional state, and social interaction.[15] As the measurements of physiological parameters alone cannot be taken surrogate markers of HRQoL, this emphasizes the need to measure QOL directly.[16] Diverse self-reported instruments have been used to assess resulting impairment like medical outcomes study survey, Short-form 36 health survey Questionnaire (SF-36), Satisfaction with Life Scale, Nottingham Health Profile, General health questionnaire-28. [17-21] These HRQoL instruments have multiple subclasses, each signifying different domains of life. Question mark on the ability of generic questionnaire to detect subtle effects of disease on QOL and effects on QOL brought about by various treatment modalities led to the development of disease specific questionnaire for OSA like Calgary sleep apnea quality of life index (SAQLI), functional outcome of sleepiness questionnaire (FOSQ), and OSA Patient-Oriented Severity Index.[22-24] These disease specific questionnaires have been compared with generic questionnaire. In a study, SAQLI was more responsive to changes in QOL in patients receiving OSA specific treatment than SF-36 and has strong content and constructive validity, but has to be administered by an interviewer.[16] These OSA specific questionnaires are being used increasingly in the newer studies and gradually replacing the generic scales. [25] A comparative study between these disease specific questionnaires have found SAQLI more sensitive than FOSQ.[26] We undertook this study to investigate the overall effect of OSA on human life and where does it affect so that a 290
complete therapy can be planned addressing the specific needs of the patient. Any treatment modality chosen on the basis of derangements in the physiological parameters only is unlikely to be complete as these parameters may not be the true representative of the extent of sufferings of the OSA patients. Thus, there is a need for a complete holistic treatment considering physiological, emotional, and social impairment of the individual patient. The HRQoL has cross-cultural and regional differences even in same clinical condition.[27] Thus, the conclusions drawn from researches done outside India cannot be used to gauge QOL impairment in Indian OSA patients. This study was the need of the hour as there has not been any such study in India.
MATERIALS AND METHODS The present study was conducted over a period of 18 months between March 2006 and August 2007, in an urban population in a North Indian City. The study was conducted after due approval from Ethics Committee of the Institute. During the 1.5 year period consecutive adult patients of either sex who had been referred for snoring, EDS, multiple sleep awakenings were screened with Berlin Questionnaire. Those scored as high-risk cases were subjected to overnight Polysomnography (PSG) following clinical and lab evaluation. Patients with an apnea/ hypopnea index ≥15 or ≥5 with symptoms of OSA were labeled as OSA cases. Those diagnosed as a case of OSA had their QOL assessed by SAQLI questionnaire. The original English version of the questionnaire developed by Flemons and Reimer was translated to the vernacular language of the patients.[22] The translated questionnaire was administered to each patient by the investigator, and the QOL was assessed by the ultimate score obtained by the patient. Subjects who had experienced chronic psychiatric disorders, alcoholism, drug abuse, psychotropic drug abuse, unstable medical disorder, other sleep disorder were excluded. Similarly, severe respiratory disease (FEV1
