Abnormal things happening during sleep: parasomnias.

Parasomnias are characterized by abnormal experiences, dreams, movements and behavior during sleep. They may occur in the middle of the sleep during REM (rapid eye movement) or NREM (non-rapid eye movement), during falling asleep or waking up. Characteristically for REM behavior disorder is an increased muscle tone although usually REM is defined by an absence of muscle tone. For these forms aggressive dreams may lead to violating bed partners or self-injury of the sleeping person. Even killing bed partners has been described. Many of the patients develop a kind of Parkinson's disease (synucleinopathies). The rate of phenoconversion is more than 30% in 5 years and nearly 100% after 15 years. There are several recommendations regarding a safe sleeping environment. Medicinal treatment consists of either melatonin or clonazepam.

Fifth metacarpal instability and its effect on hamatometacarpal arthritis patterns-a cadaver study.

Osteoarthritis (OA) of the fifth carpometacarpal joint is a rare diagnosis with most cases occurring post-traumatically. The joint's ligamentous supports have not been described extensively; however we know that the volar and intermetacarpal ligaments acts as the primary stabilizers. The major deforming forces on this joint are the extensor carpi ulnaris (ECU) dorsally and the flexor carpi ulnaris volarly, via the pisimetacarpal ligament. The aim of this study was to determine how the different joint stabilizers contribute to fifth carpometacarpal joint stability and biomechanics. We also sought to describe the OA patterns affecting the fifth carpometacarpal joint. A study was performed on 10 embalmed cadavers. The fifth carpometacarpal joint was evaluated biomechanically through ECU traction and sequential transection of the joint stabilizers. Gross macroscopic evaluation of degenerative changes in the articular surface was conducted and graded on a scale of 0-3 (with 0 representing normal cartilage with no visible lesions). Biomechanical data were available from 18 specimens (10 right; 8 left) and arthritic patterns were available from all 20 specimens (10 right; 10 left). Based on the biomechanical data, the proximal and distal intermetacarpal ligaments were found to be major contributors to stability. The volar stabilizer was a minor contributor to stability and the dorsal stabilizer was a minimal contributor to stability. OA was present in 16/20 specimens (80%) with an average arthritis grade of 1.6 on the right hand and 1.0 on the left hand. The most common site of OA was the dorso-ulnar quadrant.

[Sleep at Altitude]. / Schlaf in der Höhe.

Advancing infrastructure of mountain regions allows not only well-prepared mountaineers, but also elderly people with pre-existing illness the stay at high altitudes. Based on the hypoxic conditions, low oxygen saturation values are reached, which cause severe hypoxemia in the tissue. Symptoms of acute mountain sickness appear even at moderate altitude, which are manifested during sleep. Patients suffering from sleep apnea are at high risk, because of the obstructive ventilation disorder in combination with less oxygen availability. Concurrently, gender differences play a decisive role. Due to the respiratory stabilizing impact of estrogen, women are faster in adapting to altitude differences. A reduction of sleep duration and extended wake phases are shown, which causes lower sleep sufficiency. With continued rise of altitude, the arousal-index increases. For individual differences concerning altitude induced problems, individual acclimatization protocols are needed. Well prepared pre-acclimatization could prevent altitude induced sleep problems, as well as the treatment of such.

Right ventricle dimensions and function in response to acute hypoxia in healthy human subjects.

AIM: Acute hypoxia produces acute vasoconstriction in the pulmonary circulation with consequences on right ventricular (RV) structure and function. Previous investigations in healthy humans have been restricted to measurements after altitude acclimatization or were interrupted by normoxia. We hypothesized that immediate changes in RV dimensions in healthy subjects in response to normobaric hypoxia differ without the aforementioned constraints. METHODS: Transthoracic echocardiography was performed in 35 young, healthy subjects exposed to 11% oxygen, as well as six controls under sham hypoxia (20.6% oxygen, single blind) first at normoxia and after 30, 60, 100, 150 min of hypoxia or normoxia respectively. A subgroup of 15 subjects continued with 3-min cycling exercise in hypoxia with subsequent evaluation followed by an assessment 1 min at rest while breathing 4 L min-1 oxygen. RESULTS: During hypoxia, there was a significant linear increase of all RV dimensions (RVD1 + 29 mm, RVD2 + 42 mm, RVD3 + 41 mm, RVOT + 13 mm, RVEDA + 18 mm, P < 0.01) in the exposure group vs. the control group. In response to hypoxia, right ventricular systolic pressure (RVSP) showed a modest increase in hypoxia at rest (+7.3 mmHg, P < 0.01) and increased further with physical effort (+11.8 mmHg, P < 0.01). After 1 min of oxygen at rest, it fell by 50% of the maximum increase. CONCLUSION: Acute changes in RV morphology occur quickly after exposure to normobaric hypoxia. The changes were out of proportion to a relatively low-estimated increase in pulmonary pressure, indicating direct effects on RV structure. The results in healthy subjects are basis for future clinically oriented interventional studies in normobaric hypoxia.

Effect of weekly hiking on cardiovascular risk factors in the elderly.

BACKGROUND: Hiking is one of the most popular activities among the elderly in Alpine regions. Due to the long-lasting, moderately intensive nature of this form of physical activity, hiking is generally considered to be beneficial to health. However, it is currently unclear whether once-weekly hiking--as commonly practiced at weekends--really does yield such positive effects in elderly persons aged 60 years and over. OBJECTIVES: This study investigated the effect of a single weekly mountain hiking session on cardiovascular risk factors. MATERIALS AND METHODS: A 9-month mountain hiking program was completed by 14 male (age 65.6 ± 2.7 years) and 10 female (age 66.2 ± 4.4 years) elderly participants. The program consisted of a single weekly hiking session with the goal of achieving a 500-m altitude increase within 3 h. Before and after the 9-month program, an electrocardiogram (ECG) was performed and blood pressure, glycated hemoglobin (HbA1c), high-density (HDL) and low-density lipoprotein (LDL) measurements were made. RESULTS: The elderly participants showed a normal cardiovascular risk profile at the start of the investigation. The estimated net energy expenditure for one hiking session was approximately 521 ± 91 kcal. Over the 9-month period, no changes were found in any of the investigated parameters for the entire group. However, participants with untreated hypertension showed a reduced systolic blood pressure. CONCLUSION: The present investigation showed that moderate-intensity activity only at weekends does not improve cardiovascular risk factors in elderly persons with a relatively normal cardiovascular risk profile. Conversely, elderly persons suffering from hypertension might profit from such a practice.

Effects of supervised exercise on gamma-glutamyl transferase levels in patients with isolated impaired fasting glucose and those with impaired fasting glucose plus impaired glucose tolerance.

AIM: To study the effects of a supervised exercise program on serum gamma-glutamyl transferase (GGT), glycemic control and cardiovascular risk factors in pre-diabetic patients with isolated impaired fasting glucose (IFG) and those with IFG plus impaired glucose tolerance (IGT). METHODS: Out of 60 pre-diabetic patients (30 with isolated IFG and 30 with IFG + IGT) 24 were randomly assigned to the supervised exercise program (1 h twice a week) and 36 only obtained counselling on the risk of diabetes and its prevention. Patients have been followed over a 12-month period. RESULTS: The main findings were that patients with IFG + IGT had increased GGT levels at baseline (49.2±27.4 U/L) compared to subjects with isolated IFG (28.1±21.9 U/L) (p<0.01), and that GGT levels improved only after the supervised exercise intervention within the IFG + IGT subjects ( - 17.7±19.6 U/L). Similarly, baseline triglyceride levels were also higher in IFG + IGT patients (p<0.001) and there was a decrease through exercise intervention in these patients only (p<0.05). CONCLUSION: GGT is an unspecific marker of oxidative stress and both high plasma glucose and triglycerides levels may produce oxidative stress. Thus, patients with IFG + IGT seem to have higher levels of oxidative stress than those with isolated IFG. Based on the known association between GGT levels and cardiovascular risk factors, IFG + IGT patients may be at higher risk for the development of cardiovascular diseases. The specific effect of regular exercise on GGT in pre-diabetic patients may contribute to the understanding of the preventive effects related to exercise.

Two weeks of buspirone protects against posthypoxic ventilatory pauses in the C57BL/6J mouse strain.

The purpose was to determine if 2 weeks of buspirone suppressed post-hypoxic breathing instability and pauses in the C57BL/6J (B6) mouse. Study groups were vehicle (saline, n=8), low-dose (1.5 mg/kg, n=8), and high-dose buspirone (5.0 mg/kg, n=8). Frequency, measured by plethysmography, was the major metric, and a pause defined by breathing cessation >2.5 times the average frequency. Mice were tested after 16 days of ip injections of vehicle or drug. On day 17, 4 mice in each group were tested after buspirone and the 5-HT(1A) receptor antagonist, 4-iodo-N-{2-[4-(methoxyphenyl)-1-piperazinyl] ethyl}-N-2-pyridinyl-benzamide (p-MPPI, 5 mg/kg). A post-hypoxic pause was present in 6/8 animals given vehicle and 1/16 animals given buspirone at either dose, but always present (8/8) with p-MPPI, regardless of buspirone dose. Post-hypoxic frequency decline was blunted by buspirone (-10% vehicle vs. -5% at both doses) and restored by p-MPPI; ventilatory stability as described by the coefficient of variation which was reduced by buspirone (p<0.04) was increased by p-MPPI (0.01). In conclusion, buspirone administration after 2 weeks acts through the 5-HT(1A) receptor to reduce post-hypoxic ventilatory instability in the B6 strain.

Cromoglycate, reproterol, or both--what's best for exercise-induced asthma?

OBJECTIVE: International guidelines recommend short- (SABA) or long-acting b-agonists for the prevention of bronchoconstriction after exercise (EIB) in patients with exercise-induced asthma (EIA). However, other drugs are still in discussion for the prevention of EIB. We investigated the efficacy of a combination of inhaled sodium cromoglycate and the ß-mimetic drug reproterol versus inhaled reproterol alone and both versus inhaled placebo in subjects with exercise-induced asthma (EIA). METHODS: The study aimed to prove the preventive effect of a combination of 1-mg reproterol and 2-mg disodium cromoglycate (DSCG) and its single components vs. placebo, measuring the decrease of FEV1 after a standardized treadmill test in 11 patients with recorded EIA. The study medication was twice as high as those of drugs which are commercially available (e.g., Allergospasmin®, Aarane®). RESULTS: The results revealed that the combination of reproterol and DSCG was significantly effective against a decrease of FEV1 after a standardized exercise challenge test (ECT) compared to placebo. The short-acting b-agonist reproterol alone had almost the same effectiveness as the combination of reproterol and DNCG. The difference between the combination with DNCG and reproterol alone was less than 10% and insignificant (p 0.48). DNCG alone did not show a difference in the effectiveness compared to placebo. CONCLUSION: Prevention of EIA with the combination of reproterol and DSCG or with reproterol only is effective. An exclusive recommendation in favor of the combination cannot be given due to the low difference in the effectiveness versus reproterol alone. Due to the limited number of subjects and some probands showing protection under DSCG, it cannot be completely excluded that there is some preventive power of DSCG in individual cases.

Cheyne stokes breathing at high altitude: a helpful response or a troublemaker?

Sleep disorders at high altitude are common and well-known for centuries. One symptom of the complex is periodic breathing (PB). PB occurs from a disbalance of the negative feedback loop of ventilation control, and at high altitude, it is increased by a phase shift of 180 degrees between hyperventilation and hypoxia. This paper explains the mechanisms that trigger the problem and discusses whether PB may be of advantage or disadvantage for the person going to high altitude. Up to about 3,000-3,500 m, PB may be of advantage because it stabilizes oxygen saturation at a relatively high level. At higher altitudes, disadvantages predominate because frequent arousals cause total sleep deprivation and mental and physical impairment of the victim. Correct acclimatization and "defensive" altitude profiles are gold standard, which minimize PB and optimizes recreative sleep, although they cannot mask PB completely, especially at extreme altitude.

Telemedicine in the sleep laboratory: feasibility and economic advantages of polysomnograms transferred online.

The costs for polysomnography (PSG) and alternative diagnostic procedures for sleep-disordered breathing are challenging public health care systems. We wanted to determine if a telemedicine protocol with online transfer of PSGs from a remote site could be cost-effective and clinically useful while improving patient access to full PSG. Fifty-nine PSGs were performed in 54 pulmonary patients with suspected sleep-disordered breathing at a remote hospital. The data were transferred by File Transfer Protocol (FTP) via the Internet to Walter Reed Army Medical Center (WRAMC) for scoring and interpretation. The results were faxed back to the remote hospital. Clinical utility was assessed by evaluating the reasons for patient referral and the resulting diagnoses. The economic benefits were calculated by comparing direct expenses of the telemedicine protocol with costs for contracting PSGs at outside sleep laboratories. A total of 93% (55) of all PSGs were transferred successfully online. Of the 54 patients, 47 had PSGs performed for diagnosis (including three split-night studies), 8 underwent treatment titration, and 1 patient had both overnight studies. Diagnoses were obstructive sleep apnea in 43 patients, central sleep apnea in 2, and upper airway resistance syndrome in 2. The disease conditions were defined as severe in 27 patients, moderate in 12 patients, and mild in 8 patients. Each PSG cost $700 (including costs for lost transmissions) compared to $1,250 for referral to a private sleep laboratory. A savings of $550 per study was realized with the telemedicine protocol. The online transfer of PSGs from a remote site to a centralized sleep laboratory is technically feasible and clinically useful. Telemedicine offers an effective alternative for cost reduction in sleep medicine while improving patient access to specialized care in remote areas.

Overnight pulse oximetry for sleep-disordered breathing in adults: a review.

Pulse oximetry is a well-established tool routinely used in many settings of modern medicine to determine a patient's arterial oxygen saturation and heart rate. The decreasing size of pulse oximeters over recent years has broadened their spectrum of use. For diagnosis and treatment of sleep-disordered breathing, overnight pulse oximetry helps determine the severity of disease and is used as an economical means to detect sleep apnea. In this article, we outline the clinical utility and economical benefit of overnight pulse oximetry in sleep and breathing disorders in adults and highlight the controversies regarding its limitations as presented in published studies.

REM sleep and catecholamine excretion: a study in elite athletes.

We investigated the potential influence of catecholamines on sleep architecture in endurance-trained athletes. The hypothesis was that endogenous levels of aminergic neurotransmitters influence sleep architecture. Thirteen well-trained male street cyclists (all members of the German national amateur team, mean age 23.9 years, mean body mass index 21.9 kg/m2) completed the protocol. Each subject was studied during training after a race competition (C) and later in a recovery/rest period (R) with no training and no competition. Polysomnography (PSG) was performed for one night (C) and for a second night some weeks later (R). Urinary levels of catecholamines collected during the preceding day and over the night of PSG were used as an index of excretion rate of circulating adrenergic agonists. Nighttime and daytime excretion of epinephrine and norepinephrine was significantly elevated after exercise (C vs R; P<0.01). Rapid-eye-movement sleep (REM) onset latency was significantly increased (P=0.03) and REM was significantly decreased in the first half of the night in the training compared to the resting condition (C vs R, P=0.05). REM latency was correlated with increased epinephrine excretion on the day of exercise (C, r=0.63, P=0.02). The temporal appearance of REM during the night appears to be affected in part by the intense exercise associated with race competition, and urinary catecholamines are markers that are correlated with this alteration in REM appearance.

Application of telemedicine to sleep medicine.

Polysomnograms (PSGs) in specialized sleep centers with physicians and technicians trained in sleep medicine are still considered to be the most accurate form of diagnosis in patients with sleep disorders. But they are also very costly. Internet online transfer of PSGs from nonstaffed to very well-staffed sleep centers might be a solution in the future to reduce costs.

Using the Berlin Questionnaire to identify patients at risk for the sleep apnea syndrome.

BACKGROUND: Although sleep apnea is common, it often goes undiagnosed in primary care encounters. OBJECTIVE: To test the Berlin Questionnaire as a means of identifying patients with sleep apnea. DESIGN: Survey followed by portable, unattended sleep studies in a subset of patients. SETTING: Five primary care sites in Cleveland, Ohio. PATIENTS: 744 adults (of 1008 surveyed [74%]), of whom 100 underwent sleep studies. MEASUREMENTS: Survey items addressed the presence and frequency of snoring behavior, waketime sleepiness or fatigue, and history of obesity or hypertension. Patients with persistent and frequent symptoms in any two of these three domains were considered to be at high risk for sleep apnea. Portable sleep monitoring was conducted to measure the number of respiratory events per hour in bed (respiratory disturbance index [RDI]). RESULTS: Questions about symptoms demonstrated internal consistency (Cronbach correlations, 0.86 to 0.92). Of the 744 respondents, 279 (37.5%) were in a high-risk group that was defined a priori. For the 100 patients who underwent sleep studies, risk grouping was useful in prediction of the RDI. For example, being in the high-risk group predicted an RDI greater than 5 with a sensitivity of 0.86, a specificity of 0.77, a positive predictive value of 0.89, and a likelihood ratio of 3.79. CONCLUSION: The Berlin Questionnaire provides a means of identifying patients who are likely to have sleep apnea.

Blood flow of the middle cerebral artery with sleep-disordered breathing: correlation with obstructive hypopneas.

BACKGROUND AND PURPOSE: Epidemiological data link heavy snoring to an increased risk for stroke, an association often ascribed to hypertension and/or sleep apnea. The aim of this study was to determine whether obstructive hypopneas, central apneas, or obstructive apneas during sleep alter blood flow of the middle cerebral artery (MCA). METHODS: Doppler sonography of the MCA was performed in conjunction with nightly polysomnography in 11 men and one woman. RESULTS: A significant decline in blood flow occurred in 76% (169/223) of obstructive hypopneas and in 80% (98/123) of obstructive apneas, compared with only 14% (13/96) of central apneas (P<.0001). While duration of events was not significantly different, MCA blood flow reductions were associated only with the duration of the obstructive hypopneas (P< or =.01) and not with the duration of central (P=.17) or obstructive (P=.07) apneas. The magnitude of fall in arterial oxygen saturation from baseline correlated with a reduced blood flow with obstructive hypopneas but not with obstructive or central apneas. CONCLUSIONS: With obstructive hypopneas and obstructive apneas, MCA blood flow is more often decreased in comparison to central apneas. MCA blood flow reductions occur with longer obstructive hypopneas and with those hypopneas with greater falls in oxygen saturation. These observations indicate pathophysiology relevant to an increased risk for stroke in heavy snorers and patients with obstructive hypopneas and apneas.

[Sleep and respiration at an altitude of 6,400 m (Aconcagua, Argentina]. / Schlaf und Atmung in 6400 m Höhe (Aconcagua, Argentinien).

UNLABELLED: Persons at extreme altitudes are known to experience disturbances in the regulation of ventilation and sleep structure. However, except for simulated studies using the decompression chamber, only single events of sleep or ventilation were measured so far in field studies up to an altitude of 5800 m. Modifying a portable sleep lab (Vitalog HMS 5000), we were able to conduct 7 channel polygraphy on our ascent to the Aconcagua up to an altitude of 6400 m. METHODS: In 6 climbers (age 38-62 y, 1 f, 6 m), ECG, EOG, SaO2, chest and abdominal movements, breathing and snoring sounds, body position, nasal and oral airflow were measured 4 weeks prior to the expedition at an altitude of 500 m, at base camp (4200 m) and in 3 climbers at 6400 m (2nd base camp) at the Aconcagua mountain. All participants had a repeat study at 500 m altitude 4 weeks after the expedition. RESULTS: The total number of obstructive apnoeas and hypopnoeas (OA/H) at night increased at an altitude of 4200 m in the mean of all 6 climbers from 36 to 67.7 compared to 500 m altitude, Central Apneas and Cheyne stokes (CA/CS) increased from 6.7 to 45.2. At 6400 m altitude the OA/H fell to 3 and 4 respectively in 2 climbers and CA to 1 and 2 respectively. In one climber, suffering from recurrent snoring with oxygen desaturation at 500 m altitude level, the number of OA/H and CA/CS increased further to 201 and 322, respectively, at 6400 m. Total sleep time including the REM position increased in all 6 climbers by 10% at base camp in comparison to an altitude of 500 m. Whereas the total sleep time remained constant in the 3 climbers at 6400 m altitude, the REM position declined by 10% in comparison to base camp (4200 m). However, significant fluctuations between individuals were noticed. CONCLUSION: Although significant alterations in sleep and breathing are noticeable at altitudes above 300 m, the respiratory drive in healthy subjects provides for a regular ventilation at high frequency at the extreme altitude above 6000 m. Sleep-related breathing disturbances at low altitude appear to be amplified at high altitudes.

[Physical training of patients with sleep apnea]. / Körperliches Training bei Patienten mit Schlafapnoe.

PURPOSE: It is a common question of sleep apnoea patients in the sleep lab whether they stand a chance to decrease the symptoms and severity of their disease by physical exercise. As far as we know, there is no data about this specific question until now, even though this has been subject to speculation. A few studies, however, report on an improvement of the respiratory drive (and chemoreceptor sensitivity) after physical exercise in athletes. The aim of this study was to prove whether physical exercise in sleep apnoea patients could improve the symptoms of their disease in an open trial. METHODS: 11 Patients with mild to severe sleep apnoea syndrome (1 f, 10 m, mean age 53.8x) took part in a 6-month period of physical exercise twice a week 2 h each time under the instructions of physical therapists. Before and after the 6mo period a full PSG without CPAP or BIPAP, a bicycle exercise test with lactate profile, echocardiography, blood test, and body weight and body height measurement was performed. Statistical analysis was done using Wilcoxon ranked test and multiple regression analysis. RESULTS: There was no significant bodyweight reduction in all patients after the 6mo period of physical training, no significant difference in either basal SaO2 nor mean SaO2 and no significant improvement in physical status by the p at 4 mmol lactate on the lactate profile. Echocardiographic changes were not found; there was no significant change in the blood pressure profiles during the bicycle test. No cardiopulmonary problems including exercise-induced high blood pressure were reported during the training period. There was, however, a significant decrease of the RDI (p < 0.05), but no significant change in the REM-sleep % of total sleep time (TST) and the TST itself. CONCLUSIONS: There was an improvement of the sleep apnoea syndrome correlated to a decrease of the RDI in the studied patient population due to a possible increase in the respiratory drive or a stabilised muscle tone ine the upper airways after physical exercise, as reported by other authors, because weight reduction could not be the reason in our patients. Our trial showed that the exercise does not increase the severity of symptoms of sleep apnoea by changing the REM/non REM ratio or for any other reasons. A physical training programme for sleep apnoea patients as an additional treatment should therefore be considered.