원저 J Kor Sleep Res / Volume 7 / June, 2010 단국대학교의과대학신경과학교실 Common Side Effects and Compliance with Nasal Continuous Positive Airway Pressure in Korean OSA patients: Short-term Follow Up Seon-Min Lee, Yong-Joo Lee, Jee Hyun Kim Department of Neurology, Dankook University College of Medicine Objectives : The aim of this study was to investigate factors affecting compliance and acceptance of nasal CPAP in Korean OSA patients. Methods : Forty patients with OSA who underwent nasal CPAP titration with either full night or split night polysomnogram (PSG) at Dankook University hospital were enrolled. Sleep questionnaire, PSG results and medical records were retrospectively reviewed. The telephone interview was done for questions regarding CPAP side effects. Smart card data from nasal CPAP were reviewed. We compared CPAP trial group to patients who refused CPAP. Patients who kept using CPAP (user) were compared to patients who stopped using CPAP within a month (CPAP failure group). Follow-up duration was 7.8±2.9 months. Results : Twenty-eight patients (26 male, 45.6±8.5years) accepted CPAP trial after titration. The trial group had more prevalent history of drowsy driving, higher respiratory arousal index (RAI), higher apnea index and shorter sleep latency than no trial group. Sixty-four percent of trial group continued using nasal CPAP. The user group had significant higher BMI, higher RAI and higher ratio of supine/lateral respiratory disturbance index (RDI) than the CPAP failure group. The most common complaint in user group was mask leak whereas the CPAP failure group most commonly complained of mask discomfort and difficulty in falling asleep. Conclusions : Our study showed that 70% of OSA patients accept CPAP and among them 64% continued using CPAP. History of drowsy driving can be a good motivation factor encouraging CPAP. CPAP users were more obese and showed non-positional OSA than CPAP failure group. Key Words: Nasal CPAP, Compliance, Adherence, Sleep apnea, Acceptance 서론 Received 15 June 2010 Revised 23 June 2010 Accepted 23 June 2010 * Address of correspondence Jee Hyun Kim, MD, PhD Department of Neurology, Dankook University College of Medicine Anseo-dong San 16-5, Cheonan, Chungcheongnam-do, 330-714, Korea Tel: +82-41-550-3292 Fax: +82-41-550-6245 E-mail: fever26@paran.com 비강양압기 (Nasal continuous positive airway pressure) 는폐쇄성수면무호흡의표준치료법이며반복적인폐쇄성수면무호흡을정상호흡으로만드는효과적인치료이나지속적으로사용을해야한다는큰단점이있고사용중여러가지의불편감이따를수있는치료이다. 이로인하여환자가지속적으로사용해야하는노력이필요한치료이기때문에환자의비강양압기사용의순응도와지속적인착용여부를결정하는인자에대한관심이높고많은연구가이루어지고있다. 비강양압기의순응도 (compliance) 는연구에따라차이가많으며매일 5시간을사용하는것을 adherent 하다고하였을때대략 46-83% 가비강 Vol.7, No.1 / June, 2010 1
양압기를위와같이규칙적으로사용하지않는것으로보고되어있다 (non-adherent). 1 또한비강양압기치료의장기순응도는연구기간에따라차이가있으며최근국내한보고에의하면비강양압기사용한달후는 59.4%, 석달후는 34.7% 의순응도를보이는것으로시간이지날수록줄어드는것으로나타났다. 2 그러나아직국내에서는비강양압기치료의장기순응도및순응도에영향을미치는인자들에대한구체적연구와개선방향에대한연구가부족한실정이다. 따라서본연구에서는국내폐쇄성수면무호흡환자들의비강양압기사용의순응도및사용에영향을미치는인자들을알아보고자하였다. 또한흔하게호소하는불편감이어떤것인지함께조사하였다. 대상과방법대상본연구는 2008 년 5월부터 2009 년 4월까지단국대학교병원신경과수면다원검사실에서야간수면다원검사를통해폐쇄성수면무호흡을진단받고, 비강양압기적정압력측정검사 (CPAP titration) 를시행받은 40명의환자를대상으로하였다. 환자중 34명은하룻밤전체비강양압기압력측정검사 (Full night titration) 을시행받았고 6명은분할검사 (split night titration) 을시행받았다. 환자군은적정압력측정검사를시행후비강양압기사용을착용하기로결정한시도군과사용을거절한비시도군으로분류하였으며, 시도군은다시한달이상의지속적인사용을한사용군과사용후한달이경과하기이전에사용을포기한실패군으로구분하여분석하였다. 방법 1) 각환자군들의진료기록및수면다원검사시시행한수면설문지를후향적으로분석하여인구학적인자료및내과적질환, 정신과질환등의다른질병이환률및수면다원검사시시행한신장과체중으로계산한체질량지수와목둘레길이를포함한이학적자료를분석하였다. 또한수면설문지는폐쇄성수면무호흡증을진단받은일차수면다원 검사시에시행한것으로 Epworth Sleepiness scale (ESS) 3 과 Stanford sleepiness scale (SSS) 4 을포함한주간졸림증에대한설문, Insomnia severity scale (ISS) 5, Beck depression Index (BDI) 6 의우울증설문, 졸음운전의경험, 자신이주간증상이있어서내원한경우와배우자또는다른가족의권유에의해검사를받은경우에대한정보를포함하고있다. 수면다원검사결과를분석하여시간당무호흡- 저호흡지수 (Apnea-hypopnea index, AHI), 총호흡저하지수 (respiratory disturbance index, RDI), 각성지수 (arousal index, AI), 최저산소포화도, 자세에따른 AHI 및 RDI를포함한수면다원검사결과를분석하였다. 2) 순응도및비강양압기사용시불편감및부작용, 비강양압기사용후수면및주간기능에대한호전에대한질문은외래진료및전화를통한인터뷰를통해수집하였고순응도및총사용시간은기록이가능한환자에서비강양압기내의 smart card 의자료를분석하였다. 3) 수면다원검사수면다원검사는 6개의뇌파채널 (F3, F4, C3, C4, O1, O2), 4개의안전도 (LE, RE, SO, IO), 호흡을보기위한비강압력센서 (nasal pressure transducer of airflow, PTAF), 열전도센서 (thermistor), 호흡운동을보기위한흉곽과복부의 respiratory inductance plethysmography 센서, 다리근전도, 산소포화도와심전도의전극을부착하였다. 수면검사의판독은 2007년미국수면학회에서출간한 scoring 지침을바탕으로시행하였다. 이때저호흡에대한규칙은대안규칙을사용하였고이규칙에서는 10초이상 PTAF 의신호의감소가기저보다 50% 이상이면서 3% 이상의산소포화도의저하나또는각성이동반이되는경우로정의하였다. 비강양압술시행시에는시작압력은 5cmH 2 O에서시작하였고무호흡, 저호흡, 호흡노력관련각성및코골이가모두없어질때까지압력을순차적으로올렸다. 최종압력은훈련된수면전문의의판독에의해결정되었다. 2 수면
통계분석 비강양압기시도군과비시도군간의인구학적인자료및진단수면다원검사의결과와비강양압기압력을비교하였다. 또한비강양압기사용군과실패군의인구학적인자료와수면다원검사결과및비강양압기압력을비교하였고 Kruskal-Wallis test 및 Chi square test를시행하였다. 통계분석은 SPSS Ver.13.0 을사용하였으며통계적유의성은 P < 0.05 로설정하였다. 결과 전체조사대상군의특징 (Table 1) 연구대상군인 40명의환자들 ( 남자 34명, 여자 6명, 평균연령 47.1±10.0 세 ) 중 34명은하룻밤전체비강양압기적정압력측정검사를시행하였고 6명은분할검사로비강양압기적정압력측정검사를시행하였다. 평균체질량지수는 28.3±4.2 kg/m 2 로과체중환자들이었으며이환질환으로는고혈압이 47.5% 로많았다. 환자군의 57.5% 가운전중졸림을호소하였으며, 평균호흡저하지수는 51.2± 24.5/hr 였다. 환자들은주로신경과에서권유를받고비강양압기압력검사처방을받은환자들이많았고그외이 Table 1. Demographic data of Subjects Total (n=40) Sex Male : 34 Female : 6 Age 47.1±10.0 (28~76) Body mass index 28.3±4.2 kg/m 2 Titration Full night:34, Split night: 6 Respiratory disturbance index 51.2±24.5/hr Epworth sleepiness scale 9.8±5.2/hr Insomnia severity index 10.0±8.1 Comorbidity DM 15% (6/40) HTN 47.5% (19/40) IHD 7.5% (3/40) Stroke 15% (6/40) Referring Physician Neurology: 67.5% otorhinolaryngologist:27.5% Others : 5% History of drowsy driving 57.5% (23/40) DM; diabetes mellitus, HTN; hypertension, IHD; ischemic heart disease. 비인후과에서도일부처방을받았다. 평균 ESS 는 9.8±5.2 였고평균 ISS는 10.0±8.2였다. 비강양압기시도군과비시도군의비교 (Table 2) 비강양압기압력결정검사를마친 40명의환자중비강양압기를사용해보기로결정한시도군은 28명 (70%) 이었으 Table 2. Comparison between trial group and no trial group of CPAP Trial N=28 No trial N=12 p-value Sex (Female, %) 7.1 33.3 0.055 Age (years) 45.6±8.5 50.6±12.6 0.237 Body mass index(kg/m 2 ) 28.5±4.6 27.7±3.2 0.839 Marital Status (Married, %) 10.7 25.0 0.341 Split night titration (%) 10.7 25.0 0.341 Epworth sleepiness scale 10.4±4.6 8.3±6.5 0.089 History of drowsy driving (%) 75 16.7 0.001* Stanford sleepiness scale 3.3±1.4 3.9±1.1 0.138 Beck depression index 7.1±5.3 12.1±6.9 0.022* Insomnia severity index 9.4±7.6 11.6±9.7 0.614 CPAP pressure (cmh 2O) 10.8±2.7 11.2±3.5 0.442 Comorbidity (%) DM 10.7 25 0.341 HTN 42.9 58.3 0.369 IHD 7.1 33.3 0.869 Stoke 10.7 25 0.341 Arousal index (/hr) 43.4±20.4 21.5±10.3 0.002* Respiratory arousal index (/hr) 40.8±21.2 18.9±10.9 0.002* Apnea index (/hr) 24.1±23.8 5.1±7.4 0.007* Hypopnea index (/hr) 28.7±15.4 29.0±23.3 0.616 Lowest SaO 2 (/hr) 78.9±9.7 82.8±9.2 0.165 Mean SaO 2 (/hr) 94.9±20.3 95.8±1.9 0.072 Total RDI (/hr) 54.9±23.8 43.4±24.2 0.275 Lateral RDI (/hr) 35.6±30.7 11.7±9.5 0.100 Supine RDI (/hr) 64.4±26.1 46.0±32.5 0.326 Sleep latency (min) 4.7±5.6 12.7±14.1 0.032* REM latency (min) 122.0±80.5 130.7±73.7 0.535 Supine time (%) 63.2±25.3 72.6±25.2 0.288 Sleep Efficiency (%) 88.9±6.1 87.3±6.5 0.392 Self-referral (%)** 71.4 75 0.570 *, p value <0.05;** self-referral means that patients came to the clinic to seek the treatment due to subjective symptoms rather than being forced by bed partner or family members. CPAP; continuous positive airway pressure, DM; diabetes mellitus, HTN; hypertension, IHD; ischemic heart disease, RDI; respiratory disturbance index (apnea-hypopnea index + respiratory effort related arousal index). Vol.7, No.1 / June, 2010 3
며수술적치료의선호, 재정적인이유, 치료자체를원치않는등의이유로비강양압기의사용시도자체를거절한비시도군은 12명 (30%) 이었다. 전체 6명의여자환자중에서 2명만시도하여여자들이비강양압기를시도하지않는경향을보였다. 그외연령및체질량지수, 결혼여부, 본인이증상을느껴서검사를하게되었는지주변이나보호자의권유로검사를받았는지는비강양압기시도군과비시도군간의차이가없었으나시도군에서는운전시졸립다고보고한환자가 75%(21/28) 로비시도군의 16.7%(2/12) 에비해유의하게높았다 (p=0.001). ESS는시도군에서비시도군에비해약간높은경향을보였으나 SSS와 ISI는큰차이가없었다. 그리고우울증지수인 BDI가시도군에서비시도군에비해유의하게낮았다 (7.1±5.3 vs. 12.1±6.9, p=0.022). 수면검사결과를비교하였을때에는총호흡저하지수, 앙와위및측와위자세에서의호흡저하지수는시도군에서약간높았으나통계적으로유의하지는않았다. 그러나무호흡지수는시도군에서비시도군에비해의미있게높았고 (24.1±23.7/hr vs. 5.1±7.4/hr) 총각성지수및호흡각성이역시시도군에서의미있게높았다. 그리고수면잠복기가시도군에서의미있게짧았다. 비강양압기사용군과실패군의비교 (Table 3) 전체 40명의환자에서비강양압기를사용한 28명의시도군중한달이후에도지속적으로사용한사용군은 18명 (64.3%) 이었으며나머지 10명 (35.7%) 은한달경과이전에사용을포기하였다. 사용군과실패군을비교하였을때사용군의체질량지수가실패군에비해의미있게높았다. 수면다원검사결과를비교하였을때에는총호흡저하지수및앙와위호흡저하지수는사용군에서높은경항을보였으나통계적으로유의하지는않았다. 반면에측와위호흡저하지수는사용군에서실패군에비해유의하게높았다. 또한측와위시무호흡및저호흡의호전여부를반영하는앙와위호흡저하지수를비교시실패군에서사용군에비해유의하게훨씬높아 (8.3±8.2 vs. 2.3±1.6, p=0.010) 실패군에서는자세의변화시수면무호흡이호전되는양상이사용군에비해뚜렷함을알수있었다. 또한호흡각성 지수가사용군에서실패군에비해높았다. 수면잠복기를포함한그외의다른수면변수들은통계적으로유의한차이는없었다. 적정압력은사용군에서는 12.7±2.6 cmh 2 O 이고실패군에서는 10.0±2.2 cmh 2O로의미있게사용군에서더높았다. Table 3. Comparison between CPAP user group and CPAP failure group CPAP user N=18 CPAP failure N=10 p-value Sex (Female, %) 11.1 0 0.524 Age (years) 44.7±9.1 47.3±7.5 0.349 Body mass index(kg/m 2 ) 29.8±5.3 26.3±1.6 0.020* Marital Status (Married, %) 88.9 90.0 0.927 Split night titration (%) 11.1 10.0 0.927 Epworth sleepiness scale 11.1±4.8 9.1±4.0 0.177 History of drowsy driving (%) 72.2 80.0 0.649 Stanford sleepiness scale 3.3±1.6 3.3±1.3 0.684 Beck depression index 7.1±4.9 7.1±6.3 0.754 Insomnia severity index 9.4±7.5 9.3±8.3 0.825 CPAP pressure (cmh 2O) 12.7±2.6 10.0±2.2 0.010* Comorbidity (%) DM 11.1 10.0 0.827 HTN 50.0 30.0 0.306 IHD 11.1 10.0 0.524 Stoke 11.1 10.0 0.927 Arousal index (/hr) 48.1±21.1 34.5±17.3 0.065 Respiratory arousal index (/hr) 46.3±21.1 30.7±18.2 0.039* Apnea index (/hr) 27.8±23.1 17.3±24.5 0.084 Hypopnea index (/hr) 30.0±17.0 25.1±13.5 0.303 Lowest SaO 2 (/hr) 76.9±24.3 82.3±6.6 0.259 Mean SaO 2 (/hr) 94.4±2.0 95.6±1.8 0.250 Total RDI (/hr) 60.9±20.7 44.3±26.1 0.068 Lateral RDI (/hr) 46.7±30.6 13.5±15.6 0.005* Supine RDI (/hr) 70.6±24.3 50.8±26.1 0.050 Sleep latency (min) 5.3±6.8 3.8±2.0 0.981 REM latency (min) 129.3±86.6 109.0±70.6 0.338 Supine time (%) 61.3±26.3 66.7±24.2 0.649 Sleep Efficiency (%) 89.0±7.1 88.7±4.5 0.472 Self-referral (%)** 55.6 100 0.025* *, p value <0.05;**, self-referral means that patients came to the clinic to seek the treatment due to subjective symptoms rather than being forced by bed partner or family members. CPAP; continuous positive airway pressure, DM; diabetes mellitus, HTN; hypertension, IHD; ischemic heart disease, RDI; respiratory disturbance index (apnea-hypopnea index + respiratory effort-related arousal index). 4 수면
비강양압기사용시호소하는불편감및부작용 (Fig 1, 2) 비강양압기를시도한군에서비강양압기를사용할때느낄수있는불편감이나부작용에대해전화나병원방문시의인터뷰결과를분석하였을때사용군과실패군에서약간의차이를보였다. 사용군에서는마스크의공기누출이가장흔하게경험하는불편감이었고 (62.5%) 이어서수면중마스크탈착 (56.2%), 구강건조 (50.0%) 및공기의구강누출 (50.0%), 마스크착용시불편감 (37.5%) 의순서로응답하였다. 반면실패군에서는마스크착용시불편감이가장흔하게느끼는불편한점이었고 (77.8%) 이어서비강양압기착용시잠들기가어려움 (55.6%) 및공기의구강누출 (55.6%), 구강건조 (22.2%) 및마스크의공기누출 (22.2%) 의순서였다. 사용군에서잠들기가어렵다고응답한경우는 6.25% 에불과하였다. 사용군의비강양압기순응도및효과사용군의총추적기간은 7.8±2.9 개월 (4~12개월) 이였으며하루사용시간은평균적으로 5.0±4.2 시간이었다. 그리고주중비강양압기의비사용비율은 14.5±17.7% 로나타났다. 사용군에서비강양압기이후개선점에대해물은설문에서는 56.3% 에서주간졸림증이감소되었다고하였고 43.7% 에서아침에개운하게느낀다고보고하였다또한 43.7% 에서예전보다수면중덜깬다고대답하였다. 실제평균 ESS 도사용전 11.1±4.8 에서 5.4±4.1 로뚜렷한호전을보였다. 고찰 Figure 1. The prevalence of complaints associated with nasal CPAP usage in CPAP user group The number above each column is the percentage of the complaint. Figure 2. The prevalence of complaints associated with nasal CPAP usage in CPAP failure group The number above each column is the percentage of the complaint. 폐쇄성수면무호흡증은반복적인상기도의폐쇄로인하여저산소증및잦은각성으로인한다양한주간증상을나타내게되며심혈관계질환, 뇌졸중및대사성장애의독립적위험요인이된다. 7-10 수면중반복적인무호흡과저호흡은급성으로는교감신경계의흥분을촉진하여혈압과심박수를증가시키며만성적으로는고혈압, 뇌졸중, 관상동맥질환등으로인한심혈관계관련유병률및사망률을증가시키게된다. 7-10 따라서이학적검사및수면다원검사를통한폐쇄성수면무호흡의정확한진단과정도를파악하고치료하는것이중요하다. 폐쇄성수면무호흡의치료는비강양압기가가장효과적인치료로성인에서는표준치료로권장되고있다. 비강양압기의미국수면학회에서권장한적응증은무호흡-저호흡지수가 15/hr 이상인경우와, 무호흡-저호흡지수가 5-15/hr 이면서지나친주간졸림, 불면증, 우울증, 인지장애, 고혈압, 뇌졸중병력, 허혈성심장질환이동반되어있는경우로권장되고있다. 11 비강양압기사용은주간졸림의소실, 정상수면구조로의회복, 교통사고의감소, 혈압의하강및다른심혈관계질환의이환률감소등에유의한효과가있는것은잘알려져있으나 12 이는비강양압기를지속적으로일정시간이상꾸준히사용시에얻을수있는효과이다. 13 그러나비강양압기를시도 Vol.7, No.1 / June, 2010 5
하는많은수의환자가비강양압기를지속적으로유지하지못하여이를증가시키고비강양압기의순응도에영향을주는인자를찾으려는많은연구가여전히이루어지고있다. 본연구는총 40명의비강양압기적정압력측정을받은환자들을대상으로한연구로비강양압기를폐쇄성수면무호흡증의치료로받아들이고시도하려는환자의분율과비강양압기시도군에서약 1년이내의단기간의추적관찰기간동안의비강양압기의순응도및불편감을조사한연구이다. 환자군의평균호흡저하지수는 51.2±24.5/hr로중증폐쇄성수면무호흡을가지는환자들로 70% 에서비강양압기를시도하기로결정하였다. 이는외국의한연구에서비강양압기를쓰기로결정하는수용률이 95.5% 에비해낮은편으로 14 우리나라에서아직까지비강양압기의치료에적극적이지않음을알수있다. 외국의연구에서마찬가지로여자환자에서비강양압기를선호하지않는경향을보인경우가있었으나 14 성별은나이와결혼여부, 사회경제적지위와마찬가지로일관성을보이지는않는인자로알려져있다. 1 본연구에서는대상군의숫자가매우적어좀더많은환자를대상으로한연구가필요하다. 본연구에서흥미로운것은시도군과비시도군의중요한차이점을보인인자로운전중졸림을경험했는지의여부였다. 주간졸림증을나타내는 ESS 는약간높은경향이있었으나통계적으로유의하지않았고 SSS도뚜렷한차이가없었던반면에운전중졸림을경험한경우가시도군에서월등히높았다. 이는운전중졸림은환자에게수면무호흡증을치료할수있는동기를부여할수있는중요한주간기능장애인것으로생각되기때문에수면무호흡환자에게병력청취를함에있어중요한문항으로생각된다. 실제로많은연구에서수면무호흡이교통사고를많이증가시킨다는것을보여주고있다. 15 또한다른연구에서는기분은비강양압기를유지하는것에는큰영향이없었다고하였으나 16,17 본연구에서는시도군에서비시도군에비해우울증지수가유의하게낮아정서적인측면도양압기의시도에영향을미치는것을보여주었다. 그외시도군에서비시도군에비해총호흡저하지수나무호흡-저호흡지수에는차이가없으나각성지수특히호 흡각성지수의빈도가높았다. 이는사용군과실패군에서도보였던차이로다른연구와달리무호흡이나저호흡으로인한미세각성의빈도가비강양압기의수용및지속적인착용의예측인자로생각된다. 또한짧은수면잠복기는상대적으로비강양압기를착용하였을때의불편감을느낄기회가적어비강양압기의사용을더시도하였을것으로추측된다. 지속적으로비강양압기를사용한군과실패군의중요한차이를보인인자는체질량지수와측와위에서의수면무호흡의호전여부로옆으로누워서호전이되는경우, 즉다시말해자세치료와같은다른대안치료가있는경우에는양압기를중단하는경우가많아지는것으로생각된다. 그외에호흡각성이높은경우양압기를지속하는것으로보여진다. 기존의연구들을보았을때비강양압기를지속적으로사용하는데있어수면무호흡의심한정도는약한관련이있다고하였고 12,14 수면중의산소포화도의저하는관련이없다고하였다. 18 기존의연구에서도높은체질량지수도비강양압기를지속적으로사용하게하는결정인자중의하나였다. 14 또한높은 ESS 와같이주간증상의유무가비강양압기를지속적으로사용하게하는데중요한인자임을보여주었다. 14 그러나자세에따른수면무호흡의호전여부와같은인자에대해서는언급이없었다. 본연구에서는실제총호흡저하지수는실패군과사용군에서차이가없었으나옆으로누었을때에도뚜렷이호전이안되는군, 즉비체위성수면무호흡환자에서양압기를지속적으로사용하는것을보여지며적은수의환자를대상으로우리나라에서시행한다른연구에서도앙와위에서의자는시간이길수록비강양압기를잘사용하는것으로보고하고있다. 2 본연구에서는앙와위에서의자는시간의차이는없었으나이러한자세와의관련은한국인에서의비강양압기의사용에있어체위성수면무호흡인지비체위성수면무호흡인지가중요한인자임을시사한다. 이러한비체위성수면무호흡은높은체질량지수를가진수면무호흡환자에서보이는특징이다. 19 실패군에서는사용시가장불편한점으로마스크착용시불편감과잠들기어려운것과마스크공기누출인반면에사용군에서는착용시불편감보다는마스크의공기누출이었다. 그리고사용군에서는중간에무의식적으로마스크를 6 수면
벗는경우및구강건조도많은편이었다. 그러나사용군에서는잠들기어렵다고한경우는매우낮아실패군과의큰차이를보여초기에수면제를사용하여사용시불편감을줄이는방법을고려해볼수있을것으로생각된다. 마스크사용시불편감및공기누출을최대한막기위하여초기에개개인에맞는적절한마스크의선택과교육이필요할것으로생각되며또한사용자에서도불편감에대한사용초기의빠른개선이 CPAP 순응도를보다올릴수있을것으로생각된다. 흥미롭게도마스크의압력은사용군에서시도군에비해유의하게높았다. 이는통계적으로아주유의하진않으나사용군이총호흡저하지수가높은편이어서나타난결과로생각된다. 그러나일반적으로예상하게되는높은압력이양압기사용의순응도를낮출것이라고생각하는것에반하는결과로적절한압력을선택하여치료함이오히려순응도에중요할수있음을시사하며이는다른연구에서도유사한결과를보여주었다. 14 본연구는 40명이라는적은환자수와 1년미만의짧은추적기간으로인하여비강양압기를사용하는환자들의대표성을반영하기는한계가있다. 또한여성의비율이전체환자군의 15% 로성별에대한차이를알기에는한계가있다. 비강양압기의 1년이상의장기간동안의순응도에대한결과를알기위해서지속적인기간의연구를통한데이터의분석이더필요할것으로생각된다. REFERENCES 1. Weaver TE, Grunstein RR. Adherence to continuous positive pressure therapy: the challenge to effective treatment. Proc Am Thorac Soc 2008;5:173-178. 2. Kim JH, Kwon MS, Song HM, Lee BJ, Jang YJ, Chung YS. Compliance with positive airway pressure treatment for obstructive sleep apnea. Clin Exp Otorhinolaryngol 2009;2:90-96. 3. Johns MW. A new method for measuring daytime sleepiness: the Epworth sleepiness scale. Sleep 1991;14:540-545. 4. Hoddes E, Zarcone V, Smythe H, Phillips R, Dement WC. Quantification of sleepiness: a new approach. Psychophysiology 1973; 10:431-436. 5. Bastien CH, Vallières A, Morin CM. Validation of the Insomnia Severity Index as an outcome measure for insomnia research. Sleep Med 2001;2:297-307. 6. Beck AT, Ward CH, Mendelson M, Mock J, Erbaugh J. An inventory for measuring depression. Arch Gen Psychiatry 1961;4:561-571. 7. Peker Y, Kraiczi H, Hedner J, Löth S, Johansson A, Bende M. An independent association between obstructive sleep apnoea and coronary artery disease. Eur Respir J 1999;14:179-184. 8. Lavie P, Herer P, Hoffstein V. Obstructive sleep apnoea syndrome as a risk factor for hypertension: population study. BMJ 2000;320: 479-482. 9. Bassetti C, Aldrich MS. Sleep apnea in acute cerebrovascular diseases: final report on 128 patients. Sleep 1999;22:217-223. 10. Parish JM, Somers VK. Obstructive sleep apnea and cardiovascular disease. Mayo Clin Proc 2004;79:1036-1046. 11. Kushida CA, Littner MR, Hirshkowitz M, Morgenthaler TI, Alessi CA, Bailey D, et al. Practice parameters for the use of continuous and bilevel positive airway pressure devices to treat adult patients with sleep related breathing disorders. Sleep 2006;29:375-380 12. Gay P, Weaver T, Loube D, Iber C; Positive Airway Pressure Task Force; Standards of Practice Committee, et al. Evaluation of positive airway pressure treatment for sleep related breathing disorders in adults. Sleep 2006;29:381-401. 13. Weaver TE, Maislin G, Dinges DF, Bloxham T, George CF, Greenberg H, et al. Relationship between hours of CPAP use and achieving normal levels of sleepiness and daily functioning. Sleep 2007; 30:711-719. 14. McArdle N, Devereux G, Heidarnejad H, Engleman HM, Mackay TW, Douglas NJ. Long-term use of CPAP therapy for sleep apnea/ hypopnea syndrome. Am J Respir Crit Care Med 1999;159:1108-1114. 15. Tregear S, Reston J, Schoelles K, Phillips B. Obstructive sleep apnea and risk of motor vehicle crash: systematic review and metaanalysis. J Clin Sleep Med 2009;5:573-581. 16. Stepnowsky CJ Jr, Bardwell WA, Moore PJ, Ancoli-Israel S, Dimsdale JE. Psychologic correlates of compliance with continuous positive airway pressure. Sleep 2002;25:758-762. 17. Wells RD, Freedland KE, Carney RM, Duntley SP, Stepanski EJ. Adherence, reports of benefits, and depression among patients treated with continuous positive airway pressure. Psychosom Med 2007; 69:449-454. 18. Budhiraja R, Parthasarathy S, Drake CL, Roth T, Sharief I, Budhiraja P, et al. Early CPAP use identifies subsequent adherence to CPAP therapy. Sleep 2007;30:320-324. 19. Oksenberg A, Silverberg DS, Arons E, Radwan H. Positional vs nonpositional obstructive sleep apnea patients: anthropomorphic, nocturnal polysomnographic, and multiple sleep latency test data. Chest 1997;112:629-639. Vol.7, No.1 / June, 2010 7