Evaluation of sleep architecture and cyclic alternating pattern rates in depressed insomniac patients treated with nefazodone hydrochloride.

The standard methods of scoring sleep patterns do not ensure an accurate clinical impression of sleep quality. This is important especially in depressed insomniacs because persistent poor sleep increases the likelihood of recurrent depressive episodes. Changes in cyclic alternating patterns (CAP) in sleep have been shown to reflect corresponding changes in sleep quality. We evaluated the effects of nefazodone on CAP and standard sleep architecture in depressed insomniacs. The study was a single-center, single-blind, 6-week treatment of nefazodone hydrochloride followed by placebo withdrawal in 16 subjects meeting the DSM-IV criteria for depression who had a score of at least 18 on the 17-item Hamilton Depression Rating Scale, with insomnia-related items 4, 5, and 6 having a total score of 3 or greater. A mean daily dose of 339.1 +/- 141.7 mg at endpoint of nefazodone significantly reduced Hamilton Depression Scores from 21.7 +/- 3.0 on baseline to 5.8 +/- 5.3 (P <.05) by the end of the study. Polysomnography showed an improvement in sleep latency and sleep efficiency (P <.05), but no alterations in rapid-eye-movement or slow-wave sleep. Subjective estimates of sleep quality improved throughout the study, but CAP rates did not show a significant improvement. The disparity between CAP rates and sleep quality in depressed insomniacs is discussed.

Outcome evaluation of long-term nasal continuous positive airway pressure therapy in obstructive sleep apnea.

A study was conducted at the Tri-State Sleep Disorders Center of Cincinnati, Ohio, to evaluate both quantitative and qualitative daily function and productivity outcomes of treating obstructive sleep apnea (OSA) with nasal continuous positive airway pressure (NCPAP). This was a prospective outcome study conducted in 316 patients with diagnosed and treated OSA. There were 234 men and 82 women, mean age, 48.79 +/- 0.67 years; weight averaged 250.39 +/- 3.55 pounds; mean pretreatment respiratory disturbance index was 42.9 +/- 1.7 episodes per hour and 2.8 +/- 0.2 episodes per hour with NCPAP treatment. Patients were surveyed by questionnaire, administered on polysomnographic confirmation of OSA and after 6 months of nightly treatment with NCPAP as to their perceptions of their level of daytime functioning and quality of life over the previous 6 months. Main outcome measures included number of incidents of excessive daytime sleepiness; number of headaches on awakening; number of automobile accidents and near-miss automobile accidents; number of days absent from work; number of physician visits; and a series of subjective scales, measuring job productivity, quality of life, general physical and mental condition, short-term memory, and changes in blood pressure. Significant decreases were found in the number of incidents of excessive daytime sleepiness, headaches on awakening, physician visits, days absent from work, and automobile accidents or near misses with NCPAP therapy. Patients also reported subjective increases in productivity, quality of life, physical and mental condition, and short-term memory and reduction in both diastolic and systolic blood pressure. Effective treatment of OSA results in improvement both in preexisting symptoms and in quality of life. Improvement in many of the major problems experienced by patients seeking treatment has important implications for preventive medicine as well as health care cost containment.

Effects of estrogen replacement therapy on rates of cyclic alternating patterns and hot-flush events during sleep in postmenopausal women: a pilot study.

The objective of this pilot study was to evaluate the effects of conjugated estrogens on the rates of cyclic alternating patterns of sleep (CAPS) and nocturnal hot flushes in symptomatic postmenopausal women. Seven postmenopausal or posthysterectomy women aged 45 to 60 years with nocturnal diaphoresis and/or hot flushes participated in this study. The study was conducted with a single-masked design using a matching placebo. The placebo baseline was followed by a 4-week, single-masked treatment of conjugated estrogens 0.625 mg taken 4 hours before bedtime. Each patient's sleep was monitored in the laboratory for 3 consecutive nights during placebo baseline and again for 3 consecutive nights after an at-home period of at least 24 days of estrogen replacement therapy. Estrogen therapy resulted in a statistically significant decrease in the overall number of hot flushes and the number of hot hot flushes associated with awakenings, as well as improvement in sleep efficiency and a reduction in the rate of CAPS. These data confirm earlier well-established reports that estrogens reduce the frequency of hot flushes and suggest that the frequency of nocturnal arousals decreases and sleep quality improves in conjunction with a reduction in the rate of CAPS.

Comparative effects of sleep on a standard mattress to an experimental foam surface on sleep architecture and CAP rates.

The comparative effects of sleep patterns and rates of cyclic alternating patterns (CAP rate) in a high quality innerspring mattress were compared to those on a unique foam support mattress in 10 normal subjects. Results showed no differences in sleep stages, number of wakes, or total sleep time between the two conditions. CAP rates were significantly reduced on the foam surface. CAP rate was sensitive to the first-night effect on both surfaces, but was blunted on the foam mattress.

Effects of an external nasal dilator on sleep and breathing patterns in newborn infants with and without congestion.

BACKGROUND: We recently demonstrated that the use of an external nasal dilator reduced subjective snoring levels and improved sleep quality. Our study polysomnographically evaluated the effects of this device on the frequency of obstructive airway events during sleep in infants with and without congestion. METHODS: We used a crossover study to monitor 20 infants between the ages of 2 and 4 months (15 infants without congestion and 5 with congestion). Monitoring was conducted during two daytime sleep sessions in a crossover study in which infants slept with or without a cutdown version of an external nasal dilator (Breathe Right Nasal Strips, CNS, Inc., Bloomington, Minn.) in the first session with crossover to the other condition in the second session. A respiratory disturbance index consisting of apneas (pauses in respiration of at least 8 seconds) or hypopneas (decreased airflow resulting in oxygen desaturation of at least 3%) was determined. RESULTS: Babies without congestion showed a greater than 50% reduction in respiratory disturbance index from 3.2 +/- 2.8 to 1.2 +/- 1.2 events per hour (p < 0.005). Congested infants showed a decrease from 6.9 +/- 2.9 to 1.5 +/- 1.6 events per hour (p < 0.05). Babies with the greatest number of events showed the greatest improvement. CONCLUSION: The use of an external nasal dilator reduces the frequency of obstructive respiratory events in infants.

Cyclic alternating pattern sequences in non-apneic snorers with and without nasal dilation.

A study was conducted to polysomnographically evaluate the effects of external nasal dilation on sleep quality in mild snorers by examining the amount of sleep fragmentation and cyclic alternating pattern sequences (CAPS) rates. A two-night, open-label, one-way crossover polysomnographic evaluation, with and without use of an external nasal dilator, was done at the Tri-State Sleep Disorders Center in Cincinnati, Ohio. Nine snorers, polysomnographically determined to be free of clinically significant levels of obstructive sleep apnea, were studied. CAPS rates with nasal dilation were 28.4% as compared to 37.9% without nasal dilation (p < 0.05). We conclude that external nasal dilation reduces arousal instability in snorers without obstructive sleep apnea.

Computerized adjustable versus fixed NCPAP treatment of obstructive sleep apnea.

An automated positive airway pressure device that monitors respiratory patterns and provides dynamic, real-time, relational pressure has been developed for the treatment of obstructive sleep apnea (OSA). The purpose of this study was to compare self-adjusting pressure to classical nasal continuous positive airway pressure (NCPAP). Subjects were newly diagnosed patients with a minimum respiratory disturbance index (RDI) of 15 episodes per hour who had undergone NCPAP titration and been using classical NCPAP at home on a nightly basis for at least 2 weeks. Patients then underwent repeat standard polysomnographic (PSG) evaluations for 2 nights using a self-adjusting pressure mode and a standard NCPAP mode randomly assigned in a single-blind crossover fashion. Eight males and four females (n = 12), aged 48.4 +/- 12.2 years [mean +/- and standard deviation (SD)], completed the study. During initial diagnostic PSG, the RDI was 57.3 +/- 30.8 episodes per hour. The RDI and minimum oxygen saturation for both treatment nights were significantly improved from those of the diagnostic PSGs (p < 0.001). The subjects spent 63.1 +/- 34.2% of total sleep time below prescribed pressure while on automatic pressure Percent of total sleep time in stage 3/4 sleep was significantly higher during self-adjusting pressure, at 8.6 +/- 7.5%, compared to standard NCPAP, at 4.6 +/- 6.0% (p < 0.05). Computerized adjustable nasal positive airway pressure effectively controls OSA, fluidly providing the minimal pressure necessary to control respiratory events without causing sleep disruption.