The Experts below are selected from a list of 22035 Experts worldwide ranked by ideXlab platform
Einar Wildersmith - One of the best experts on this subject based on the ideXlab platform.
-
stimulated skin wrinkling as an indicator of limb Sympathetic Function
Clinical Neurophysiology, 2015Co-Authors: Einar WildersmithAbstract:Abstract Skin wrinkling upon water immersion has been used as an indicator of limb nerve Function for more than 80 years. Until recently, routine use of the test has been hampered by a poor understanding of the physiology and lack of standardization. The process underlying stimulated skin wrinkling has been recently identified as dependent on digital vasoconstriction mediated via Sympathetic nerve fibers. Vasoconstriction is postulated to drive wrinkling through loss of digit volume, which induces a negative pressure in the digit pulp and exerts a downward pull on the overlying skin and ultimately results in wrinkles. Improved test standardization has been achieved through substituting water with EMLA for inducing skin wrinkling. This has made testing much easier and has helped implement stimulated skin wrinkling as a practical routine clinical bedside test. A literature search identified 10 studies of sufficient quality for evaluating stimulated skin wrinkling as a diagnostic test of Sympathetic under or over Function. Seven studies provide level 1 or 2 evidence as a diagnostic test of small fiber neuropathy and three provide level 1 or 2 evidence for cystic fibrosis. There is reasonable evidence allowing the test to be employed as a simple and effective marker for small fiber neuropathy and cystic fibrosis.
-
water immersion wrinkling physiology and use as an indicator of Sympathetic Function
Clinical Autonomic Research, 2004Co-Authors: Einar WildersmithAbstract:: Water immersion skin wrinkling is an indicator of limb Sympathetic Function. Routine clinical usage of this enigmatic phenomenon is hampered by poor endpoint quantification, which involves counting skin folds. The recent discovery of the importance of vasoconstriction in immersion wrinkling suggests digital blood flow or volume changes as better endpoints. Water probably initiates the wrinkling process by altering epidermal electrolyte homeostasis as it diffuses into the porous skin of the hands and soles via its many sweat ducts. Altered epidermal electrolyte homeostasis would lead to a change in membrane stability of the surrounding dense network of nerve fibers and trigger increased vasomotor firing with subsequent vasoconstriction. Vasoconstriction, through loss of volume, leads to negative digit pulp pressure resulting in a downward pull on the overlying skin, which wrinkles as it is distorted. The degree of wrinkling would directly depend on the change in digit tip volume and implies any process inducing loss of digit volume will precipitate wrinkling. This review discusses the physiology of water immersion wrinkling and explores its potential as an indicator of limb Sympathetic dysFunction.
S Sasayama - One of the best experts on this subject based on the ideXlab platform.
-
plasma leptin levels and cardiac Sympathetic Function in patients with obstructive sleep apnoea hypopnoea syndrome
Thorax, 2002Co-Authors: Kouichi Shimizu, Kazuo Chin, Ryuji Nohara, Ryohei Hosokawa, Takaya Nakamura, Hiroaki Masuzaki, Yoshihiro Ogawa, Akio Niimi, Noboru Hattori, S SasayamaAbstract:Background: The control of body weight and cardiac Sympathetic Function in patients with obstructive sleep apnoea-hypopnoea syndrome (OSAHS) are important because both factors have significant effects on the mortality of these patients. It has recently been reported that OSAHS has a significant effect on the secretion of leptin, a hormone involved in the control of body weight and Sympathetic nerve activity. In addition to the circadian rhythm of leptin secretion, the effects of one night of treatment with nasal continuous positive airway pressure (nCPAP) and the mechanism of the effects of nCPAP on nocturnal leptin secretion in patients with OSAHS has not yet been elucidated. Methods: Blood samples were obtained at 21.00 hours, 00.00 hours, 03.00 hours, and 06.30 hours from 21 subjects with OSAHS (mean apnoea and hypopnoea index 52.4/h), with and without nCPAP treatment. Iodine-123 (I123)-meta-iodobenzylguanidine (MIBG) imaging was used to evaluate myocardial Sympathetic Function before nCPAP treatment. Results: Plasma leptin reached a peak level at 00:00 hours (p<0.01) in patients with OSAHS, both with and without nCPAP treatment. The first night of nCPAP treatment significantly decreased the plasma leptin levels at 03.00 hours (without nCPAP: mean (SE) 21.6 (4.7) ng/ml; with nCPAP: 19.3 (4.1) ng/ml, p<0.02) and at 06.30 hours (without nCPAP: 17.6 (3.8) ng/ml; with nCPAP: 15.2 (3.2) ng/ml, p<0.01). The magnitude of the decrease in leptin levels after nCPAP treatment was significantly correlated with cardiac Sympathetic Function measured before nCPAP treatment (p<0.03). Conclusions: Patients with OSAHS undergo nocturnal increases in leptin levels in spite of interruption of sleep due to apnoea and hypopnoea, a trend seen in normal subjects. Plasma leptin levels in patients with OSAHS decreased significantly after the first night of nCPAP treatment. Enhanced cardiac Sympathetic Function in these patients may contribute to the leptin levels before nCPAP treatment and vice versa.
-
Plasma leptin levels and cardiac Sympathetic Function in patients with obstructive sleep apnoea-hypopnoea syndrome
Thorax, 2002Co-Authors: Kouichi Shimizu, Kazuo Chin, Ryuji Nohara, Ryohei Hosokawa, Takaya Nakamura, Hiroaki Masuzaki, Yoshihiro Ogawa, Akio Niimi, Noboru Hattori, S SasayamaAbstract:Background: The control of body weight and cardiac Sympathetic Function in patients with obstructive sleep apnoea-hypopnoea syndrome (OSAHS) are important because both factors have significant effects on the mortality of these patients. It has recently been reported that OSAHS has a significant effect on the secretion of leptin, a hormone involved in the control of body weight and Sympathetic nerve activity. In addition to the circadian rhythm of leptin secretion, the effects of one night of treatment with nasal continuous positive airway pressure (nCPAP) and the mechanism of the effects of nCPAP on nocturnal leptin secretion in patients with OSAHS has not yet been elucidated. Methods: Blood samples were obtained at 21.00 hours, 00.00 hours, 03.00 hours, and 06.30 hours from 21 subjects with OSAHS (mean apnoea and hypopnoea index 52.4/h), with and without nCPAP treatment. Iodine-123 (I123)-meta-iodobenzylguanidine (MIBG) imaging was used to evaluate myocardial Sympathetic Function before nCPAP treatment. Results: Plasma leptin reached a peak level at 00:00 hours (p
Kouichi Shimizu - One of the best experts on this subject based on the ideXlab platform.
-
plasma leptin levels and cardiac Sympathetic Function in patients with obstructive sleep apnoea hypopnoea syndrome
Thorax, 2002Co-Authors: Kouichi Shimizu, Kazuo Chin, Ryuji Nohara, Ryohei Hosokawa, Takaya Nakamura, Hiroaki Masuzaki, Yoshihiro Ogawa, Akio Niimi, Noboru Hattori, S SasayamaAbstract:Background: The control of body weight and cardiac Sympathetic Function in patients with obstructive sleep apnoea-hypopnoea syndrome (OSAHS) are important because both factors have significant effects on the mortality of these patients. It has recently been reported that OSAHS has a significant effect on the secretion of leptin, a hormone involved in the control of body weight and Sympathetic nerve activity. In addition to the circadian rhythm of leptin secretion, the effects of one night of treatment with nasal continuous positive airway pressure (nCPAP) and the mechanism of the effects of nCPAP on nocturnal leptin secretion in patients with OSAHS has not yet been elucidated. Methods: Blood samples were obtained at 21.00 hours, 00.00 hours, 03.00 hours, and 06.30 hours from 21 subjects with OSAHS (mean apnoea and hypopnoea index 52.4/h), with and without nCPAP treatment. Iodine-123 (I123)-meta-iodobenzylguanidine (MIBG) imaging was used to evaluate myocardial Sympathetic Function before nCPAP treatment. Results: Plasma leptin reached a peak level at 00:00 hours (p<0.01) in patients with OSAHS, both with and without nCPAP treatment. The first night of nCPAP treatment significantly decreased the plasma leptin levels at 03.00 hours (without nCPAP: mean (SE) 21.6 (4.7) ng/ml; with nCPAP: 19.3 (4.1) ng/ml, p<0.02) and at 06.30 hours (without nCPAP: 17.6 (3.8) ng/ml; with nCPAP: 15.2 (3.2) ng/ml, p<0.01). The magnitude of the decrease in leptin levels after nCPAP treatment was significantly correlated with cardiac Sympathetic Function measured before nCPAP treatment (p<0.03). Conclusions: Patients with OSAHS undergo nocturnal increases in leptin levels in spite of interruption of sleep due to apnoea and hypopnoea, a trend seen in normal subjects. Plasma leptin levels in patients with OSAHS decreased significantly after the first night of nCPAP treatment. Enhanced cardiac Sympathetic Function in these patients may contribute to the leptin levels before nCPAP treatment and vice versa.
-
Plasma leptin levels and cardiac Sympathetic Function in patients with obstructive sleep apnoea-hypopnoea syndrome
Thorax, 2002Co-Authors: Kouichi Shimizu, Kazuo Chin, Ryuji Nohara, Ryohei Hosokawa, Takaya Nakamura, Hiroaki Masuzaki, Yoshihiro Ogawa, Akio Niimi, Noboru Hattori, S SasayamaAbstract:Background: The control of body weight and cardiac Sympathetic Function in patients with obstructive sleep apnoea-hypopnoea syndrome (OSAHS) are important because both factors have significant effects on the mortality of these patients. It has recently been reported that OSAHS has a significant effect on the secretion of leptin, a hormone involved in the control of body weight and Sympathetic nerve activity. In addition to the circadian rhythm of leptin secretion, the effects of one night of treatment with nasal continuous positive airway pressure (nCPAP) and the mechanism of the effects of nCPAP on nocturnal leptin secretion in patients with OSAHS has not yet been elucidated. Methods: Blood samples were obtained at 21.00 hours, 00.00 hours, 03.00 hours, and 06.30 hours from 21 subjects with OSAHS (mean apnoea and hypopnoea index 52.4/h), with and without nCPAP treatment. Iodine-123 (I123)-meta-iodobenzylguanidine (MIBG) imaging was used to evaluate myocardial Sympathetic Function before nCPAP treatment. Results: Plasma leptin reached a peak level at 00:00 hours (p
Kazuo Chin - One of the best experts on this subject based on the ideXlab platform.
-
Corrected QT dispersion and cardiac Sympathetic Function in patients with obstructive sleep apnea-hypopnea syndrome.
Chest, 2004Co-Authors: Takaya Nakamura, Motoharu Ohi, Kazuo Chin, Ryohei Hosokawa, Ken-ichi Takahashi, Kensuke Sumi, Michiaki MishimaAbstract:Study objectives: Hypoxemia increases corrected QT dispersion (QTcD), which is the difference between the maximum and minimum QT intervals and is a strong risk factor for cardiovascular mortality. The aim of this study was to investigate the QTcD in patients with obstructive sleep apnea-hypopnea syndrome (OSAHS), and the relationship between the QTcD and 123 I-metaiodobenzylguanidine (MIBG) cardiac imaging, which reflects cardiac Sympathetic activity. Setting: A university hospital. Patients: Forty-eight OSAHS patients without cardiac diseases (mean [ SD] age, 45.9 10.8 years; apnea-hypopnea index [AHI] 51.9 18.5 events per hour) who underwent polysomnography before treatment and on the first night of nasal continuous positive airway pressure (nCPAP) treatment. Methods: Before and after nCPAP treatment was started, we measured the QTcD with computer software, before, during, and after sleep, as well as the washout rate of the MIBG administered for cardiac imaging. As a control, QTcD was also measured in the morning from 26 healthy subjects. Results: Before treatment, the mean QTcD during sleep (65.0 14.6 ms) was greater than that before sleep (57.0 13.5 ms; p < 0.0001). Meanwhile, after 1 night of nCPAP therapy, the QTcD during sleep (50.6 11.4 ms) decreased from that before treatment (p < 0.0001) and was smaller than the QTcD before sleep (56.2 13.3 ms; p 0.003). Before treatment, the QTcD during sleep correlated with the AHI (r 0.38; p 0.009) and the percentage of time that SaO2 was < 90% (SaO2 < 90% time) [r 0.34; p 0.018]. The QTcD did not correlate with the body mass index or the washout rate of MIBG. However, the washout rate of MIBG correlated with the AHI and the SaO2 < 90% time. Conclusions: Nocturnal QTcD is increased in OSAHS patients but is decreased by nCPAP therapy independently of cardiac Sympathetic Function. (CHEST 2004; 125:2107–2114)
-
Plasma leptin levels and cardiac Sympathetic Function in patients with obstructive sleep apnoea-hypopnoea syndrome
Thorax, 2002Co-Authors: Kouichi Shimizu, Kazuo Chin, Ryuji Nohara, Ryohei Hosokawa, Takaya Nakamura, Hiroaki Masuzaki, Yoshihiro Ogawa, Akio Niimi, Noboru Hattori, S SasayamaAbstract:Background: The control of body weight and cardiac Sympathetic Function in patients with obstructive sleep apnoea-hypopnoea syndrome (OSAHS) are important because both factors have significant effects on the mortality of these patients. It has recently been reported that OSAHS has a significant effect on the secretion of leptin, a hormone involved in the control of body weight and Sympathetic nerve activity. In addition to the circadian rhythm of leptin secretion, the effects of one night of treatment with nasal continuous positive airway pressure (nCPAP) and the mechanism of the effects of nCPAP on nocturnal leptin secretion in patients with OSAHS has not yet been elucidated. Methods: Blood samples were obtained at 21.00 hours, 00.00 hours, 03.00 hours, and 06.30 hours from 21 subjects with OSAHS (mean apnoea and hypopnoea index 52.4/h), with and without nCPAP treatment. Iodine-123 (I123)-meta-iodobenzylguanidine (MIBG) imaging was used to evaluate myocardial Sympathetic Function before nCPAP treatment. Results: Plasma leptin reached a peak level at 00:00 hours (p
-
plasma leptin levels and cardiac Sympathetic Function in patients with obstructive sleep apnoea hypopnoea syndrome
Thorax, 2002Co-Authors: Kouichi Shimizu, Kazuo Chin, Ryuji Nohara, Ryohei Hosokawa, Takaya Nakamura, Hiroaki Masuzaki, Yoshihiro Ogawa, Akio Niimi, Noboru Hattori, S SasayamaAbstract:Background: The control of body weight and cardiac Sympathetic Function in patients with obstructive sleep apnoea-hypopnoea syndrome (OSAHS) are important because both factors have significant effects on the mortality of these patients. It has recently been reported that OSAHS has a significant effect on the secretion of leptin, a hormone involved in the control of body weight and Sympathetic nerve activity. In addition to the circadian rhythm of leptin secretion, the effects of one night of treatment with nasal continuous positive airway pressure (nCPAP) and the mechanism of the effects of nCPAP on nocturnal leptin secretion in patients with OSAHS has not yet been elucidated. Methods: Blood samples were obtained at 21.00 hours, 00.00 hours, 03.00 hours, and 06.30 hours from 21 subjects with OSAHS (mean apnoea and hypopnoea index 52.4/h), with and without nCPAP treatment. Iodine-123 (I123)-meta-iodobenzylguanidine (MIBG) imaging was used to evaluate myocardial Sympathetic Function before nCPAP treatment. Results: Plasma leptin reached a peak level at 00:00 hours (p<0.01) in patients with OSAHS, both with and without nCPAP treatment. The first night of nCPAP treatment significantly decreased the plasma leptin levels at 03.00 hours (without nCPAP: mean (SE) 21.6 (4.7) ng/ml; with nCPAP: 19.3 (4.1) ng/ml, p<0.02) and at 06.30 hours (without nCPAP: 17.6 (3.8) ng/ml; with nCPAP: 15.2 (3.2) ng/ml, p<0.01). The magnitude of the decrease in leptin levels after nCPAP treatment was significantly correlated with cardiac Sympathetic Function measured before nCPAP treatment (p<0.03). Conclusions: Patients with OSAHS undergo nocturnal increases in leptin levels in spite of interruption of sleep due to apnoea and hypopnoea, a trend seen in normal subjects. Plasma leptin levels in patients with OSAHS decreased significantly after the first night of nCPAP treatment. Enhanced cardiac Sympathetic Function in these patients may contribute to the leptin levels before nCPAP treatment and vice versa.
-
Assessment of Cardiac Sympathetic Function with Iodine-123-MIBG Imaging in Obstructive Sleep Apnea Syndrome
Journal of nuclear medicine : official publication Society of Nuclear Medicine, 1997Co-Authors: Naoki Otsuka, Motoharu Ohi, Kazuo Chin, Hideo Kita, Tetsuo Noguchi, Tatsuhiko Hata, Ryuji Nohara, Ryohei Hosokawa, Masatoshi Fujita, Kenshi KunoAbstract:UNLABELLED Iodine-123-MIBG imaging has been used to evaluate myocardial Sympathetic Function in various cardiac diseases. In patients with obstructive sleep apnea syndrome (OSAS), increased Sympathetic activity has been widely recognized, as assessed by measuring the plasma concentration and urinary excretion of catecholamines and by measuring muscle Sympathetic nerve activity. However, these measurements are not specific indices of cardiac Sympathetic Function. Therefore, this study was undertaken to assess cardiac Sympathetic Function in patients with OSAS using MIBG cardiac scintigraphy. METHODS This study consisted of 11 patients (10 men, 1 woman; mean age 43 +/- 16 yr) with a diagnosis of OSAS established by polysomnography, and 8 age-matched normal control subjects (7 men, 1 woman; mean age 45 +/- 18 yr). Early (15 min) and delayed (3 hr) planar images were taken after the injection of 111 MBq of [123I]MIBG. The mean counts of the whole heart and the mediastinum were obtained to calculate heart-to-mediastinum count ratios from the early images (H/Me) and from the delayed images (H/Md) and the myocardial washout rate (WR). Eight patients were restudied after 1 mo of nasal continuous positive airway pressure treatment. RESULTS The H/Me and H/Md ratios were significantly lower in the patients than in the control subjects (H/Me, 2.49 +/- 0.32 versus 2.84 +/- 0.34, p = 0.0207; and H/Md, 2.33 +/- 0.30 versus 3.02 +/- 0.36, p = 0.0013). The WR was higher in the patients than in the control subjects (36.2 +/- 9.0% versus 23.6 +/- 4.9%, p = 0.0022). The H/Me and H/Md ratios in the patients were significantly correlated with the apnea-hypopnea index and the degree of hypoxemia during sleep. After treatment, H/Me and H/Md remained unchanged, but WR significantly recovered (from 34.9 +/- 10.4% to 26.3 +/- 7.7%, p = 0.0357). CONCLUSION Cardiac Sympathetic Function and integrity are impaired in subjects with OSAS when compared with age-matched control subjects. MIBG cardiac imaging can be helpful in evaluating cardiac involvement and efficacy of therapy in OSAS.
Ryohei Hosokawa - One of the best experts on this subject based on the ideXlab platform.
-
Corrected QT dispersion and cardiac Sympathetic Function in patients with obstructive sleep apnea-hypopnea syndrome.
Chest, 2004Co-Authors: Takaya Nakamura, Motoharu Ohi, Kazuo Chin, Ryohei Hosokawa, Ken-ichi Takahashi, Kensuke Sumi, Michiaki MishimaAbstract:Study objectives: Hypoxemia increases corrected QT dispersion (QTcD), which is the difference between the maximum and minimum QT intervals and is a strong risk factor for cardiovascular mortality. The aim of this study was to investigate the QTcD in patients with obstructive sleep apnea-hypopnea syndrome (OSAHS), and the relationship between the QTcD and 123 I-metaiodobenzylguanidine (MIBG) cardiac imaging, which reflects cardiac Sympathetic activity. Setting: A university hospital. Patients: Forty-eight OSAHS patients without cardiac diseases (mean [ SD] age, 45.9 10.8 years; apnea-hypopnea index [AHI] 51.9 18.5 events per hour) who underwent polysomnography before treatment and on the first night of nasal continuous positive airway pressure (nCPAP) treatment. Methods: Before and after nCPAP treatment was started, we measured the QTcD with computer software, before, during, and after sleep, as well as the washout rate of the MIBG administered for cardiac imaging. As a control, QTcD was also measured in the morning from 26 healthy subjects. Results: Before treatment, the mean QTcD during sleep (65.0 14.6 ms) was greater than that before sleep (57.0 13.5 ms; p < 0.0001). Meanwhile, after 1 night of nCPAP therapy, the QTcD during sleep (50.6 11.4 ms) decreased from that before treatment (p < 0.0001) and was smaller than the QTcD before sleep (56.2 13.3 ms; p 0.003). Before treatment, the QTcD during sleep correlated with the AHI (r 0.38; p 0.009) and the percentage of time that SaO2 was < 90% (SaO2 < 90% time) [r 0.34; p 0.018]. The QTcD did not correlate with the body mass index or the washout rate of MIBG. However, the washout rate of MIBG correlated with the AHI and the SaO2 < 90% time. Conclusions: Nocturnal QTcD is increased in OSAHS patients but is decreased by nCPAP therapy independently of cardiac Sympathetic Function. (CHEST 2004; 125:2107–2114)
-
Plasma leptin levels and cardiac Sympathetic Function in patients with obstructive sleep apnoea-hypopnoea syndrome
Thorax, 2002Co-Authors: Kouichi Shimizu, Kazuo Chin, Ryuji Nohara, Ryohei Hosokawa, Takaya Nakamura, Hiroaki Masuzaki, Yoshihiro Ogawa, Akio Niimi, Noboru Hattori, S SasayamaAbstract:Background: The control of body weight and cardiac Sympathetic Function in patients with obstructive sleep apnoea-hypopnoea syndrome (OSAHS) are important because both factors have significant effects on the mortality of these patients. It has recently been reported that OSAHS has a significant effect on the secretion of leptin, a hormone involved in the control of body weight and Sympathetic nerve activity. In addition to the circadian rhythm of leptin secretion, the effects of one night of treatment with nasal continuous positive airway pressure (nCPAP) and the mechanism of the effects of nCPAP on nocturnal leptin secretion in patients with OSAHS has not yet been elucidated. Methods: Blood samples were obtained at 21.00 hours, 00.00 hours, 03.00 hours, and 06.30 hours from 21 subjects with OSAHS (mean apnoea and hypopnoea index 52.4/h), with and without nCPAP treatment. Iodine-123 (I123)-meta-iodobenzylguanidine (MIBG) imaging was used to evaluate myocardial Sympathetic Function before nCPAP treatment. Results: Plasma leptin reached a peak level at 00:00 hours (p
-
plasma leptin levels and cardiac Sympathetic Function in patients with obstructive sleep apnoea hypopnoea syndrome
Thorax, 2002Co-Authors: Kouichi Shimizu, Kazuo Chin, Ryuji Nohara, Ryohei Hosokawa, Takaya Nakamura, Hiroaki Masuzaki, Yoshihiro Ogawa, Akio Niimi, Noboru Hattori, S SasayamaAbstract:Background: The control of body weight and cardiac Sympathetic Function in patients with obstructive sleep apnoea-hypopnoea syndrome (OSAHS) are important because both factors have significant effects on the mortality of these patients. It has recently been reported that OSAHS has a significant effect on the secretion of leptin, a hormone involved in the control of body weight and Sympathetic nerve activity. In addition to the circadian rhythm of leptin secretion, the effects of one night of treatment with nasal continuous positive airway pressure (nCPAP) and the mechanism of the effects of nCPAP on nocturnal leptin secretion in patients with OSAHS has not yet been elucidated. Methods: Blood samples were obtained at 21.00 hours, 00.00 hours, 03.00 hours, and 06.30 hours from 21 subjects with OSAHS (mean apnoea and hypopnoea index 52.4/h), with and without nCPAP treatment. Iodine-123 (I123)-meta-iodobenzylguanidine (MIBG) imaging was used to evaluate myocardial Sympathetic Function before nCPAP treatment. Results: Plasma leptin reached a peak level at 00:00 hours (p<0.01) in patients with OSAHS, both with and without nCPAP treatment. The first night of nCPAP treatment significantly decreased the plasma leptin levels at 03.00 hours (without nCPAP: mean (SE) 21.6 (4.7) ng/ml; with nCPAP: 19.3 (4.1) ng/ml, p<0.02) and at 06.30 hours (without nCPAP: 17.6 (3.8) ng/ml; with nCPAP: 15.2 (3.2) ng/ml, p<0.01). The magnitude of the decrease in leptin levels after nCPAP treatment was significantly correlated with cardiac Sympathetic Function measured before nCPAP treatment (p<0.03). Conclusions: Patients with OSAHS undergo nocturnal increases in leptin levels in spite of interruption of sleep due to apnoea and hypopnoea, a trend seen in normal subjects. Plasma leptin levels in patients with OSAHS decreased significantly after the first night of nCPAP treatment. Enhanced cardiac Sympathetic Function in these patients may contribute to the leptin levels before nCPAP treatment and vice versa.
-
Assessment of Cardiac Sympathetic Function with Iodine-123-MIBG Imaging in Obstructive Sleep Apnea Syndrome
Journal of nuclear medicine : official publication Society of Nuclear Medicine, 1997Co-Authors: Naoki Otsuka, Motoharu Ohi, Kazuo Chin, Hideo Kita, Tetsuo Noguchi, Tatsuhiko Hata, Ryuji Nohara, Ryohei Hosokawa, Masatoshi Fujita, Kenshi KunoAbstract:UNLABELLED Iodine-123-MIBG imaging has been used to evaluate myocardial Sympathetic Function in various cardiac diseases. In patients with obstructive sleep apnea syndrome (OSAS), increased Sympathetic activity has been widely recognized, as assessed by measuring the plasma concentration and urinary excretion of catecholamines and by measuring muscle Sympathetic nerve activity. However, these measurements are not specific indices of cardiac Sympathetic Function. Therefore, this study was undertaken to assess cardiac Sympathetic Function in patients with OSAS using MIBG cardiac scintigraphy. METHODS This study consisted of 11 patients (10 men, 1 woman; mean age 43 +/- 16 yr) with a diagnosis of OSAS established by polysomnography, and 8 age-matched normal control subjects (7 men, 1 woman; mean age 45 +/- 18 yr). Early (15 min) and delayed (3 hr) planar images were taken after the injection of 111 MBq of [123I]MIBG. The mean counts of the whole heart and the mediastinum were obtained to calculate heart-to-mediastinum count ratios from the early images (H/Me) and from the delayed images (H/Md) and the myocardial washout rate (WR). Eight patients were restudied after 1 mo of nasal continuous positive airway pressure treatment. RESULTS The H/Me and H/Md ratios were significantly lower in the patients than in the control subjects (H/Me, 2.49 +/- 0.32 versus 2.84 +/- 0.34, p = 0.0207; and H/Md, 2.33 +/- 0.30 versus 3.02 +/- 0.36, p = 0.0013). The WR was higher in the patients than in the control subjects (36.2 +/- 9.0% versus 23.6 +/- 4.9%, p = 0.0022). The H/Me and H/Md ratios in the patients were significantly correlated with the apnea-hypopnea index and the degree of hypoxemia during sleep. After treatment, H/Me and H/Md remained unchanged, but WR significantly recovered (from 34.9 +/- 10.4% to 26.3 +/- 7.7%, p = 0.0357). CONCLUSION Cardiac Sympathetic Function and integrity are impaired in subjects with OSAS when compared with age-matched control subjects. MIBG cardiac imaging can be helpful in evaluating cardiac involvement and efficacy of therapy in OSAS.
