Response of obstructive sleep apnea to fluoxetine and protriptyline

Protripyline is the pharmacologic agent most commonly used to treat obstructive sleep apnea (OSA); however, its anticholinergic side effects make it intolerable to many patients. Because serotonin may be a central respiratory stimulant and because the serotonin-uptake inhibitor, fluoxetine, is usually well tolerated, we wanted to try fluoxetine in the treatment of OSA. Therefore, we compared the effect of fluoxetine to that of protriptyline in 12 patients with OSA. Both drugs significantly decreased the proportion of REM sleep time and decreased the number of apneas or hypopneas in NREM sleep. The response to fluoxetine was equivalent to that of protriptyline; however, for the group as a whole, there was no significant improvement in the number of arterial oxygen desaturation events, the level of arterial oxygen desaturation, or the number of arousals with either agent. Although there was wide variability in the response to each medication, six of the 12 patients had good responses, including improvement in oxygenation, to either fluoxetine or protriptyline. Three patients could not complete the trial of protriptyline. We conclude that fluoxetine is beneficial to some, but not all, patients with OSA. Fluoxetine was better tolerated than protriptyline.

[Therapy of sleep apnea with theophylline (Uniphylline) administration every evening]

Sleep apnoea (SA) has a prevalence of 1-10% in men. The physiological sleep is disturbed. SA is associated with cardiopulmonary disease (systemic arterial hypertension, cardiac arrhythmics, cor pulmonale) and the quality of the patient's life is reduced. Thirty male patients participated in a study to investigate the influence of an oral dose of theophylline on sleep apnoea. Under theophylline a significant reduction of apnoea events and of the apnoea index was seen.

[Long-term follow-up of sleep apnea therapy with sustained-release theophylline administered every evening]

Sleep apnoea increases mortality and morbidity. The physiological sleep profile is disturbed and functional capacity is decreased. At present nasal CPAP breathing (continuous positive airway pressure) seems to be the best treatment method in obstructive sleep apnoea. However, this therapy is expensive, imposing a strain on the patient, and hence some patients will not tolerate it. Medical treatment of sleep apnoea with theophylline has proved effective. In 40 patients suffering from sleep apnoea, long-term treatment with sustained-release theophylline was investigated. Responders show a significant reduction of apnoeic phases and of apnoea index at the beginning and after long-term treatment. Using an individual theophylline dosage with morning theophylline concentration between 5 and 8 micrograms/ml, only few side-effects occurred. Positive effects on cardiopulmonary capacity could be detected. The Broca index does not change significantly. Sustained-release theophylline applied in the evening showed a positive effect on sleep apnoea in responders.

First experience with cilazapril in the treatment of sleep apnoea-related hypertension

Sleep-related breathing disorders are associated with considerably impaired vitality and reduced life expectancy. In this respect, a particularly important role is played by obstructive snoring and obstructive or mixed sleep apnoea. Because of the often underestimated prevalence of sleep-related breathing disorders and their association with hypertension in greater than 50% of patients, it is important to introduce antihypertensive drug therapy that does not exacerbate the effects and the degree of these disorders, and that above all produces an adequate lowering of blood pressure by night. In the present study in 12 patients, it has been shown that the new ACE inhibitor, cilazapril, achieves a good reduction in blood pressure over 24 hours and during all stages of sleep, without any negative influence on the ratio of REM: nonREM sleep. The apnoea index was reduced from 40 (range 12 to 84) to 27 (range 0 to 72) apnoeas per hour of sleep (p less than 0.01). It will be increasingly important to take into account the effects of antihypertensive therapy on other clinical parameters, especially the nocturnal blood pressure profile and its association with sleep-related breathing disorders.

Influence of antihypertensive drug therapy on sleep pattern and sleep apnea activity

Sleep apnea, which affects 10% of men in the mean age group, is a common illness, and arterial hypertension one of its early symptoms. For the large group of, mainly young, patients with mild to moderate sleep apnea and arterial hypertension it is important to have a drug treatment available which will effectively control blood pressure without exacerbating symptoms of sleep apnea. We studied the effects of antihypertensive agents on blood pressure, sleep and sleep apnea in a randomized double-blind study of 24 patients with a sleep apnea activity of more than 10 apnea phases per hour of sleep and arterial hypertension with diastolic blood pressure values in the sitting position greater than or equal to 95 mm Hg. Mean age was 51 (range: 33-69) years, mean body mass index 31.4 (24.9-40.6) kg/m2. The study protocol envisaged two baseline measurements in the sleep laboratory, after which the medication was administered for 8 days. On the last 2 days of the treatment, polysomnographic leads were once again recorded in the sleep laboratory. The patients received either the beta-blocker metoprolol (1 x 100 mg/day) or the angiotensin-converting enzyme inhibitor cilazapril (1 x 2.5 mg/day). Systolic and diastolic blood pressure were decreased by both substances as expected. Total sleep time was 358 (233-425) min vs. 332 (255-383) min in the metoprolol group and 368 (295-424) min vs. 341 (265-434) min in the cilazapril group which is statistically not different between the two groups nor between the proportions of non-REM and REM sleep.(ABSTRACT TRUNCATED AT 250 WORDS)

Drug therapy of sleep-related hypoxaemia

In patients with chronic obstructive pulmonary disease (COPD) exhibiting daytime hypoxaemia, a worsening of the latter occurs during sleep, particularly during REM sleep. The most efficient therapy of this sleep-related hypoxaemia is the nocturnal administration of O2 at a flow rate of 1.5-3 l/min. An alternative therapy, when daytime hypoxaemia is not too severe (PaO2 greater than 55 mmHg), is the use of almitrine (100 mg/day), a drug which improves daytime hypoxaemia in most COPD patients. The improvement of sleep hypoxaemia with almitrine is related to the increased daytime PaO2 and cannot be considered as a specific effect of almitrine on sleep-related respiratory events. It must be emphasized that almitrine is ineffective in about 25% of COPD patients ("nonresponders") and that almitrine can be used with conventional O2 therapy in patients with severe hypoxemia (daytime PaO2 less than 55 mmHg).

Influence of metoprolol and cilazapril on blood pressure and on sleep apnea activity

Up to 50% of hypertensive men are subject to sleep apnea (SA). With a prevalence in men of up to 10%, SA is a common illness and hypertension (HT) one of its early symptoms. It is important to have available a drug treatment that will effectively control blood pressure (BP) without exacerbating symptoms of SA. Twelve patients with SA and HT were investigated in a double-blind, comparative trial. Patients were randomly allocated to either metoprolol (M) 100 mg daily or cilazapril (C) 2.5 mg daily. Polysomnographic measurements under standardized conditions including intraarterial BP monitoring were taken on two consecutive nights each before and after the 1-week treatment. Values in the M group were (mean +/- 95% CI) systolic BP 161 +/- 2.1 vs. 148 +/- 2.2 mm Hg (p less than 0.01); diastolic BP 98 +/- 1.8 vs. 93 +/- 1.8 mm Hg (p less than 0.01); and HR 73 +/- 1.2 vs 65 +/- 1.1 beats/min (p less than 0.01). Corresponding figures for the C group were systolic BP 140 +/- 2.1 vs. 127 +/- 2.1 mm Hg (p less than 0.01); diastolic BP 95 +/- 1.7 vs. 78 +/- 1.7 mm Hg (p less than 0.01); and HR 82 +/- 1.1 vs. 79 +/- 1.2 beats/min (p less than 0.01). Whereas C reduced both BP and HR in all sleep phases, M produced no changes during REM sleep. SA activity was 45 (range 15-91) vs. 34 (range 2-57) apneas per hour of sleep in the M group and 54 (range 21-84) vs. 40 (range 8-72) apneas per hour in the C group (p less than 0.01). There were no changes in total sleep time or in the proportions of non-REM to REM sleep. Both M and C reduce nocturnal BP in SA patients, but the effect of C is seen in all sleep phases. C has a more favorable effect on the disturbed nocturnal blood pressure of SA patients.

Recent advances in sudden infant death syndrome: possible autonomic dysfunction of the airways in infants at risk

Epidemiological studies of sudden infant death syndrome (SIDS) reveal a progressive increase in the incidence of cases, suggesting that the in utero environment and postneonatal care were less than optimal. Subtle differences in symptoms could indicate that, since birth, the SIDS infants are different from control infants, some having an autonomic dysfunction of the airway controls. These observations could contribute to a better understanding of some of the causes of sudden death in infants and could eventually lead to new therapeutic approaches.

[The choice between theophylline and caffeine in the treatment of apnea in premature infants]

In a double blind study, two comparable groups (each n = 10) of premature infants less than 34 weeks of gestational age, with idiopathic apnea were given an IV treatment of either theophylline or caffeine. The loading doses were respectively 6 and 10 mg/kg and the maintenance doses were 2 and 1.25 mg/kg every 12 hours. In both groups, apneas greater than or equal to 15 s. with or without bradycardia were similarly reduced (p less than 0.01). Both drugs increased significantly the respiratory rate. Compared to caffeine, theophylline induced a significant acceleration of heart rates, an increase in urinary sodium excretion, more frequent gastrointestinal intolerance and behavioral changes. Plasma concentrations of theophylline were less stable than those of caffeine. These data suggest that a single daily dose of caffeine should be preferentially used in the treatment of idiopathic apneas of prematurity.

[Effect of methylxanthines on periodic respiration and acid gastroesophageal reflux in newborn infants]

The treatment of neonatal apnea and bradycardia with methylated xanthines--theophylline and caffeine--is generally accepted. Besides the desired effects of these drugs they induce a wide range of side effects including relaxation of smooth muscles and increased gastric secretion. The aims of this study were, at first to investigate the coincidence of periodic breathing (PA) and acid gastro-esophageal reflux (GER) in neonates (n = 15) without therapy; at second to examine the influence of the consecutive medication with theophylline and caffeine on these parameters in patients (n = 10) with recurrent episodes of bradycardia and apnea. A 24 h esophageal pH-monitoring and 24 h cardiorespirography were performed simultaneously under standarized conditions. In the 15 neonates studied a weak correlation was found between the time spent breathing periodically and the duration of GER; the overlap of PB and GER was minimal. Theophylline and caffeine medication resulted in a marked reduction of PB which was more pronounced than it could be expected from maturation. The total time of a 24 h esophageal pH-monitoring was subdivided in an early postprandial time (FPP: first two hours after the beginning of a meal) and a late postprandial time (SPP: remaining time until the following meal). An increased duration of acid GER was observed during the SPP under therapy with theophylline and even more distinct with caffeine treatment.

Clinical neuropharmacology of sleep

Sleep affects, and is in turn affected by, cardiovascular, thermal, respiratory, endocrine, circadian, and sensory processes. Integrative areas of the basal forebrain play a crucial role, as does interaction with cholinergic and aminergic areas of the brain stem. AD, which affects a wide range of structures and functions, alters sleep in a manner distinguishable from depressive pseudodementia and may involve changes in autonomic function. Sleep apnea occurs with a high incidence in patients with AD, and the possibility should be explored that treating sleep apnea might be beneficial to their cognitive and affective status. Long-acting hypnotics can adversely affect daytime functioning. This might occur because of either direct effects on structures mediating sleep and cognition or, alternatively, exacerbation of sleep-related respiratory dysfunction. Studies of the benzodiazepine receptor complex may lead to the development of new drugs to aid sleep and wakefulness.

Naltrexone therapy of apnea in children with elevated cerebrospinal fluid beta-endorphin

Previous studies have indicated increased immunoreactivity of the endogenous opioid peptide beta-endorphin in the cerebrospinal fluid (CSF) of infants under 2 years of age with apnea. To assess the role of endogenous opioids in the pathogenesis of apnea in children, the effect of oral treatment with the opioid antagonist naltrexone was studied in apneic infants, as well as in older apneic children, with demonstrated increases in CSF immunoreactive beta-endorphin (i-BE). In the 8 apneic infants with elevated i-BE in lumbar CSF (range, 55-155 pg/ml; normal, 17-52 pg/ml), no further apnea occurred during naltrexone therapy (1 mg/kg/day, by mouth). Five children (2-8 years old) with apnea of unknown cause had elevated CSF i-BE (range, 74-276 pg/ml) compared to 6 age-matched nonapneic children (range, 15-48 pg/ml). No apneic events occurred during naltrexone therapy, except in 1 child during stressful events, but apnea recurred in some patients after attempts to discontinue naltrexone treatment. Adverse effects of naltrexone included complaints of headaches in 2 children and symptoms of a narcotic withdrawal syndrome during the first 3 days of treatment in 1 child. Three children with Leigh's syndrome had elevated CSF i-BE (range, 104-291 pg/ml) and their apnea also responded to naltrexone. We conclude that elevated endogenous opioids contribute to the pathogenesis of apnea in children and may even result in physical dependence.

[Relation between dose, plasma concentration and therapeutic effect of theophylline in children with sleep apnea]

The plasma concentration of theophylline was determined in twelve children with infantile sleep apnea (average age 48.5 days). The purpose of the study was to correlate concentrations with the dosages given, the therapeutic response and any adverse effects which could arise. In addition, other pharmacokinetic values were found, half-life (t 1/2) and clearance concentrations (Clss). The oral maintenance dose used was 4 mg/kg/24 h. The serum concentration of theophylline was determined by a homogeneous immunoassay enzyme technique (EMIT). A bad correlation was found (r = 0.45) between the oral dosage given and the plasma concentrations found. This was probably due to variations in the clearance of the drug. Yet, plasma concentrations fell between 3.0 and 12.6 micrograms/mL, enough to satisfactorily control apneic episodes in all the children included in the study without undesirable side-effects. Only one patient had some trouble in falling asleep and showed signs of irritability. The half-life was 13.30 +/- 7.46 hours and Clss was 36.64 +/- 12.98 mL/h/kg. In general, our results correlate with those reported in the literature. The accuracy of the pharmacokinetic parameters with two samples is reliable, therefore avoiding the use of multiple sampling in this group of children.

[Treatment of nocturnal bronchial asthma]

To date, the pathogenesis of nocturnal bronchiale asthma has not been completely clarified. For the treatment of nocturnal asthma that fails to respond to beta-2-sympathomimetics or inhalative glucocorticosteroids, theophylline in a delayed release form or delayed-release oral beta-2-sympathomimetics are available. In a double-blind crossover study, 10 patients with nocturnal or early-morning bronchial asthma were treated for one week with theophylline 390-900 mg daily (1/3 of the total dose being given in the morning, 2/3 in the evening) and one week with terbutaline 15 mg daily (7.5 mg in the morning and 7.5 mg in the evening). No significant differences were observed with respect to the measured peak flow values in the night and early morning. However, those receiving terbutaline more frequently required the additional application of inhalative beta-2-sympathomimetics for respiratory distress. Thus, the sustained-release form of theophylline is the more suitable drug for the treatment of nocturnal bronchial asthma. As a further study revealed, the sole administration of a sustained-release form of theophylline in the evening suffices. In the future, apart from theophylline in a delayed-release form, inhalative beta-2-sympathomimetics with a long-term effect will play an important role in the treatment of nocturnal breathing disorders.

[Long-term effects of treatment with SMS 201-995 on sleep apnea syndrome associated with acromegaly]

A 60-year-old woman with acromegaly associated with sleep apnea was treated with the somatostatin analogue SMS 201-995 (Sandoz) for several months. Growth hormone levels were normalized and a rapid improvement in sleep apnea was controlled with polygraphic nocturnal monitoring. Hypophysectomy seems to have variable effects on sleep apnea in acromegaly. The origin of obstructive apnea in acromegaly is therefore unclear.

[Medical treatment of sleep apneas]

The authors review the medical treatment of the sleep apnea syndrome. They also discuss the mechanical possibilities such as continuous positive airway pressure ventilation. The limits of these various treatments are presented in order to better define the indications for upper airway surgery.

Indices of severity of obstructive sleep apnea syndrome do not change during medroxyprogesterone acetate therapy

Medroxyprogesterone acetate (MPA) could change the frequency and/or duration of disordered breathing events (DBEs) in patients with the obstructive sleep apnea (OSA) syndrome by altering pharyngeal muscle function relative to diaphragm and external intercostal function. Ten male patients with OSA syndrome underwent an initial polysomnogram with monitoring of EEG, EOG, myohyoid EMG, oral and nasal airflow, abdominal and thoracic movement, and SaO2. The patients were then entered into a randomized, double-blind crossover study using MPA, 150 mg/day, and MPA placebo. Each patient took tablets for one week and then had a second polysomnogram. After a three week washout, the patient again took tablets for a week prior to the third and final sleep study. There was no significant difference between drug and placebo for DBE time (expressed as a percentage of sleep time), DBE frequency, DBE mean duration or mean fall in O2 saturation during DBEs. We conclude that treatment with MPA does not alter indices of severity of the OSA syndrome.

Progesterone therapy for sleep apnea syndrome evaluated by occlusion pressure responses to exogenous loading

We investigated the mechanisms of the beneficial effect derived from progesterone therapy for sleep apnea syndrome (SAS). Nine patients with SAS were treated for 7 days with chlormadinone acetate (CMA), a respiratory stimulant known to increase not only CO2 and hypoxic chemosensitivity but also respiratory drive response for ventilatory loading. They were examined as to sleep events and ventilatory control during wakefulness before and during CMA treatment. Apnea-hypopnea index was significantly reduced from 51.1 +/- 5.7 to 43.6 +/- 8.1 episodes/h (p less than 0.05). The ratio of desaturation time with more than 4% SaO2 fall to total sleep time was diminished in seven of nine patients, and its mean value decreased from 44.9 +/- 8.6 to 28.7 +/- 8.1% (p less than 0.05). Both hypercapnic ventilatory response (HCVR) and load response during wakefulness were significantly increased, although isocapnic hypoxic ventilatory response (HVR) was not significantly enhanced by CMA. The degree of augmentation in awake load response as well as in HCVR was positively correlated with that of improvement in sleep-disordered breathing. Moreover, patients who did not show amelioration in oxygen desaturation were found to be incapable of increasing load response despite increased HCVR. We conclude that CMA therapy for sleep apnea syndrome is effective in the patients whose load response as well as respiratory control activity are augmented during wakefulness.

Progestin and estrogen reduce sleep-disordered breathing in postmenopausal women

Women exhibit sleep-disordered breathing syndromes less commonly than men before but not after the age of menopause, suggesting that female hormones may exert a protective effect. We sought to determine whether combined progestin and estrogen treatment decreased sleep-disordered breathing in healthy postmenopausal women. Nine ovarihysterectomized women [50 +/- 2 (SE) yr of age] were studied after 1 wk of treatment with placebo (lactose) or combined progestin and estrogen (medroxyprogesterone acetate, 20 mg tid, and Premarin, 1.25 mg bid). Subjects showed few respiratory disturbances during placebo treatment. Despite this, combined progestin and estrogen administration reduced the number of sleep-disordered breathing episodes in every subject, decreasing the average number of episodes per subject from 15 +/- 4 to 3 +/- 1. The duration of hypopneas also decreased with hormone treatment. Thus the presence of progestin and estrogen may be involved in protecting premenopausal women against sleep-disordered breathing.