International Consensus Statement on Obstructive Sleep Apnea.

BACKGROUND: Evaluation and interpretation of the literature on obstructive sleep apnea (OSA) allows for consolidation and determination of the key factors important for clinical management of the adult OSA patient. Toward this goal, an international collaborative of multidisciplinary experts in sleep apnea evaluation and treatment have produced the International Consensus statement on Obstructive Sleep Apnea (ICS:OSA). METHODS: Using previously defined methodology, focal topics in OSA were assigned as literature review (LR), evidence-based review (EBR), or evidence-based review with recommendations (EBR-R) formats. Each topic incorporated the available and relevant evidence which was summarized and graded on study quality. Each topic and section underwent iterative review and the ICS:OSA was created and reviewed by all authors for consensus. RESULTS: The ICS:OSA addresses OSA syndrome definitions, pathophysiology, epidemiology, risk factors for disease, screening methods, diagnostic testing types, multiple treatment modalities, and effects of OSA treatment on multiple OSA-associated comorbidities. Specific focus on outcomes with positive airway pressure (PAP) and surgical treatments were evaluated. CONCLUSION: This review of the literature consolidates the available knowledge and identifies the limitations of the current evidence on OSA. This effort aims to create a resource for OSA evidence-based practice and identify future research needs. Knowledge gaps and research opportunities include improving the metrics of OSA disease, determining the optimal OSA screening paradigms, developing strategies for PAP adherence and longitudinal care, enhancing selection of PAP alternatives and surgery, understanding health risk outcomes, and translating evidence into individualized approaches to therapy.

INCREASING SLEEP DURATION IS ASSOCIATED WITH GEOGRAPHIC ATROPHY AND AGE-RELATED MACULAR DEGENERATION.

PURPOSE: Sleeping too much or too little has been associated with adverse health outcomes including total mortality, cardiovascular disease, Type 2 diabetes, and hypertension. This study explored the relationship between sleep patterns and age-related macular degeneration (AMD). METHODS: One thousand and three consecutive patients in a retina practice were prospectively surveyed regarding sleep histories. Each patient then had a masked ophthalmic examination and was graded on the modified Wisconsin Age-Related Maculopathy System. The relationship between AMD grade and sleep hours was analyzed in a logistic regression model. Multivariable analysis was performed after adjustment for age, gender, and smoking history. RESULTS: In multivariable analysis, controlling for age, gender, and smoking history, sleep hours are not associated with neovascular AMD (P = 0.97) but are associated with geographic atrophy (P = 0.02). Sleeping >8 hours is associated with geographic atrophy (age-adjusted odds ratio, 7.09; 95% confidence interval, 1.59-31.6) compared with patients without AMD. CONCLUSION: Longer sleep duration is associated with geographic atrophy secondary to AMD. These altered sleep patterns may be another morbidity of AMD, but further study is necessary.

Hypoglossal nerve stimulation improves obstructive sleep apnea: 12-month outcomes.

Reduced upper airway muscle activity during sleep is a key contributor to obstructive sleep apnea pathogenesis. Hypoglossal nerve stimulation activates upper airway dilator muscles, including the genioglossus, and has the potential to reduce obstructive sleep apnea severity. The objective of this study was to examine the safety, feasibility and efficacy of a novel hypoglossal nerve stimulation system (HGNS; Apnex Medical, St Paul, MN, USA) in treating obstructive sleep apnea at 12 months following implantation. Thirty-one subjects (35% female, age 52.4 ± 9.4 years) with moderate to severe obstructive sleep apnea and unable to tolerate positive airway pressure underwent surgical implantation and activation of the hypoglossal nerve stimulation system in a prospective single-arm interventional trial. Primary outcomes were changes in obstructive sleep apnea severity (apnea-hypopnea index, from in-laboratory polysomnogram) and sleep-related quality of life [Functional Outcomes of Sleep Questionnaire (FOSQ)]. Hypoglossal nerve stimulation was used on 86 ± 16% of nights for 5.4 ± 1.4 h per night. There was a significant improvement (P < 0.001) from baseline to 12 months in apnea-hypopnea index (45.4 ± 17.5 to 25.3 ± 20.6 events h(-1) ) and Functional Outcomes of Sleep Questionnaire score (14.2 ± 2.0 to 17.0 ± 2.4), as well as other polysomnogram and symptom measures. Outcomes were stable compared with 6 months following implantation. Three serious device-related adverse events occurred: an infection requiring device removal; and two stimulation lead cuff dislodgements requiring replacement. There were no significant adverse events with onset later than 6 months following implantation. Hypoglossal nerve stimulation demonstrated favourable safety, feasibility and efficacy.

Periodic leg movements are associated with reduced sleep quality in older men: the MrOS Sleep Study.

STUDY OBJECTIVES: Periodic limb movements in sleep (PLMS) are common in the elderly. A previous large polysomnographic (PSG) study examining the relationship of PLMS to sleep architecture and arousals from sleep in women found that leg movements were common in elderly women, and PLMS which were associated with EEG arousals had a strong and consistent association with markers of disturbed sleep. Since sleep differs in men and women, we now investigate the association between PLMS and PSG indices of sleep quality in a large community-based sample of older men. DESIGN: Observational study, cross-sectional analyses. SETTING: Six clinical sites participating in the Osteoporotic Fractures in Men (MrOS) Study. PARTICIPANTS: 2,872 older community-dwelling men (mean age 76.4 years) who completed in-home PSG from 2003-2005. INTERVENTIONS: N/A. MEASUREMENTS AND RESULTS: In-home PSG was performed which included bilateral measurement of leg movements. The total number of leg movements per hour of sleep (PLMI) and the number of leg movements causing EEG-documented arousals per hour of sleep (PLMA) were computed. A PLMI ≥ 5 (70.8%) and PLMA ≥ 5 (27.4%) were both prevalent. Linear regression models were used to examine the relationship between PLMS as predictors and sleep architecture, arousal index, and sleep efficiency as outcomes. The highest quintiles of PLMI (≥ 65.1) and PLMA (≥ 6.8) showed the largest association with indices of sleep architecture; PLMA showed a larger magnitude of effect. After multivariate adjustment, participants with a higher PLMA had a small but significantly higher arousal index, lower sleep efficiency, higher percentages of stages 1 and 2 sleep, and lower percentages of stage 3-4 and REM sleep (p < 0.01). An increased PLMI was similarly associated with a higher arousal index, higher percentage of stage 2 sleep, and lower percentage of stage 3-4 (p < 0.0001), but not with an increase in stage 1, REM sleep, or sleep efficiency. Neither PLMI nor PMLA was associated with subjective sleepiness measured by the Epworth Sleepiness Scale. CONCLUSIONS: This study demonstrated that periodic leg movements are very common in older community-dwelling men and regardless of associated arousals, are associated with evidence of lighter and more fragmented sleep.

HIV infection is associated with diffusing capacity impairment in women.

Respiratory dysfunction is common with HIV infection, but few studies have directly assessed whether HIV remains an independent risk factor for pulmonary function abnormalities in the antiretroviral therapy era. Additionally, few studies have focused on pulmonary outcomes in HIV+ women. We tested associations between risk factors for respiratory dysfunction and pulmonary outcomes in 63 HIV+ and 36 HIV-uninfected women enrolled in the Women's Interagency HIV Study. Diffusing capacity (DL(CO)) was significantly lower in HIV+ women (65.5% predicted vs. 72.7% predicted, P = 0.01), and self-reported dyspnea in HIV+ participants was associated with both DL(CO) impairment and airflow obstruction. Providers should be aware that DL(CO) impairment is common in HIV infection, and that either DL(CO) impairment or airflow obstruction may cause respiratory symptoms in this population.

Disturbed sleep among COPD patients is longitudinally associated with mortality and adverse COPD outcomes.

OBJECTIVE: To investigate the cross-sectional association between COPD severity and disturbed sleep and the longitudinal association between disturbed sleep and poor health outcomes. METHODS: Ninety eight adults with spirometrically-confirmed COPD were recruited through population-based, random-digit telephone dialing. Sleep disturbance was evaluated using a 4-item scale assessing insomnia symptoms as: difficulty falling asleep, nocturnal awakening, morning tiredness, and sleep duration adequacy. COPD severity was quantified by: FEV(1) and COPD Severity Score, which incorporates COPD symptoms, requirement for COPD medications and oxygen, and hospital-based utilization. Subjects were assessed one year after baseline to determine longitudinal COPD exacerbations and emergency utilization and were followed for a median 2.4 years to assess all-cause mortality. RESULTS: Sleep disturbance was cross-sectionally associated with cough, dyspnea, and COPD Severity Score, but not FEV(1). In multivariable logistic regression, controlling for sociodemographics and body-mass index, sleep disturbance longitudinally predicted both incident COPD exacerbations (OR=4.7; p=0.018) and respiratory-related emergency utilization (OR=11.5; p=0.004). In Cox proportional hazards analysis, controlling for the same covariates, sleep disturbance predicted poorer survival (HR=5.0; p=0.013). For all outcomes, these relationships persisted after also controlling for baseline FEV(1) and COPD Severity Score. CONCLUSIONS: Disturbed sleep is cross-sectionally associated with worse COPD and is longitudinally predictive of COPD exacerbations, emergency health care utilization, and mortality.

Obstructive sleep apnea: a risk factor for work disability.

STUDY OBJECTIVE: To examine obstructive sleep apnea (OSA) as a risk factor for work disability. PATIENTS AND SETTING: Consecutive patients referred to the University of California San Francisco Sleep Disorders Center with suspected OSA (n = 183). DESIGN: All patients underwent overnight polysomnography after completing a written survey which assessed work disability due to sleep problems, occupational characteristics and excessive daytime sleepiness (EDS) defined as an Epworth Sleepiness Scale score > 10. RESULTS: Among 150 currently employed patients, 83 had OSA on polysomnography (apnea-hypopnea index > or = 5). Compared with patients in whom both OSA and EDS were absent, patients with the combination of OSA and EDS were at higher risk of both recent work disability (adjusted odds ratio [OR], 13.7; 95% confidence interval [CI], 3.9-48) and longer-term work duty modification (OR, 3.6; CI, 1.1-12). When either OSA or EDS were absent, the strength of the association with work disability was less than when both OSA and EDS were present. When OSA was examined without respect to EDS, patients with OSA were at increased risk of recent work disability relative to patients without OSA (OR 2.6; 95% CI 1.2-5.8), but the association of OSA with longer-term work duty modification did not meet standard criteria for statistical significance (OR = 2.0, 95% CI 0.8-5.0). CONCLUSIONS: The combination of OSA and EDS contributes to work disability, and OSA by itself contributes to recent work disability. These findings should highlight to employers and clinicians the importance of OSA in the workplace to encourage patients to be screened for OSA, particularly in situations of decreased productivity associated with EDS.

Behavioral correlates of sleep-disordered breathing in older men.

STUDY OBJECTIVES: To examine the association between sleep-disordered breathing (SDB) and subjective measures of daytime sleepiness, sleep quality, and sleep-related quality of life in a large cohort of community-dwelling older men and to determine whether any association remained after adjustment for sleep duration. DESIGN: Cross-sectional. The functional outcome measures of interest were daytime sleepiness (Epworth Sleepiness Scale, ESS), sleep-related symptoms (Pittsburgh Sleep Quality Index, PSQI), and sleep-related quality of life (Functional Outcomes of Sleep Questionnaire, FOSQ). Analysis of variance and adjusted regression analyses examined the association between these outcome measures and SDB severity and actigraphy-determined total sleep time (TST). We then explored whether associations with SDB were confounded by sleep duration by adjusting models for TST. SETTING: Community-based sample in home and research clinic settings. PARTICIPANTS: Two-thousand eight-hundred forty-nine older men from the multicenter Osteoporotic Fractures in Men Study that began in 2000. All participants underwent in-home polysomnography for 1 night and wrist actigraphy for a minimum of 5 consecutive nights. INTERVENTIONS: N/A. MEASUREMENTS AND RESULTS: Participants were aged 76.4 + 5.5 years and had an apnea-hypopnea index (AHI) of 17.0 + 15.0. AHI and TST were weakly correlated. ESS scores individually were modestly associated with AHI and TST, but the association with AHI was attenuated by adjustment for TST. PSQI and FOSQ scores were largely not associated with measures of SDB severity but were modestly associated with TST. CONCLUSIONS: Daytime sleepiness, nighttime sleep disturbances, and sleep-related quality of life were modestly associated with TST. After adjustment for TST, there was no independent association with SDB severity. These results underscore the potential differences in SDB functional outcomes in older versus young and middle-aged adults.

Actigraphy-measured sleep characteristics and risk of falls in older women.

BACKGROUND: Prior studies have suggested that insomnia and self-reported poor sleep are associated with increased risk of falls. However, no previous study, to our knowledge, has tested the independent associations of objectively estimated characteristics of sleep and risk of falls, accounting for the use of commonly prescribed treatments for insomnia. METHODS: Study subjects were participants in the Study of Osteoporotic Fractures. In 2978 primarily community-dwelling women 70 years and older (mean age, 84 years), sleep and daytime inactivity were estimated using wrist actigraphy data collected for a minimum of 3 consecutive 24-hour periods (mean duration, 86.3 hours). Fall frequency during the subsequent year was ascertained by a triannual questionnaire. Use of medications was obtained by examiner interview. RESULTS: In multivariate-adjusted models, relative to those with "normal" nighttime sleep duration (>7 to 8 hours per night), the odds of having 2 or more falls in the subsequent year was elevated for women who slept 5 hours or less per night (odds ratio, 1.52; 95% confidence interval, 1.03-2.24). This association was not explained by the use of benzodiazepines. Indexes of sleep fragmentation were also associated with an increased risk of falls. For example, women with poor sleep efficiency (<70% of time in bed spent sleeping) had 1.36-fold increased odds of falling compared with others (odds ratio, 1.36; 95% confidence interval, 1.07-1.74). CONCLUSION: Short nighttime sleep duration and increased sleep fragmentation are associated with increased risk of falls in older women, independent of benzodiazepine use and other risk factors for falls.

Behavioral correlates of sleep-disordered breathing in older women.

STUDY OBJECTIVES: To examine the association between SDB and subjective measures of daytime sleepiness, sleep quality, and sleep related quality of life in a large cohort of primarily community-dwelling older women, specifically considering the relative importance of sleep duration in mediating these associations. DESIGN: Cross-sectional. The functional outcome measures of interest were daytime sleepiness (using the Epworth Sleepiness Scale, ESS), sleep-related symptoms (Pittsburgh Sleep Quality Index, PSQI), and sleep related quality of life (Functional Outcomes of Sleep Questionnaire, FOSQ). ANOVA and regression analyses examined the association between SDB severity (measured by indices of breathing disturbances and overnight oxygen saturation) and sleep time (by actigraphy) and these outcome measures. Regression models were adjusted for age, body mass index (BMI), and a medical comorbidity index. We specifically explored whether associations with indices of SDB were mediated by sleep deprivation by adjusting models for actigraphy-determined average total sleep time (TST) during the night. SETTING: Community-based sample examined in home and outpatient settings. PARTICIPANTS: 461 surviving older women from the multicenter Study of Osteoporotic Fractures were examined during Visit 8 from 2002-03. All participants underwent in-home overnight polysomnography for one night and wrist actigraphy for a minimum of 3 24-h periods and completed the above functional outcomes questionnaires. INTERVENTIONS: N/A. MEASUREMENTS AND RESULTS: Participants were aged 82.9 +/- 3.5 (mean +/- SD) years, had BMI of 27.9 +/- 5.1 kg/m2, and had an apnea-hypopnea index (AHI) of 15.7 +/- 15.1. AHI and TST demonstrated a weak correlation (r = -0.15). ESS score individually demonstrated a modest association with AHI, oxygen desaturation, and TST. The association of ESS score and AHI--but not oxygen desaturation-was attenuated to some extent by adjustment for TST. PSQI and FOSQ scores were not associated with measures of SDB severity or TST. CONCLUSIONS: After adjustment for TST, SDB severity in community-dwelling older women was not independently associated with self-reported daytime sleepiness, although there may be a modest association that is mediated through reduced TST. In older women, SDB severity was not associated with indices of sleep related symptoms or sleep related quality of life.

Clinical guidelines for the use of unattended portable monitors in the diagnosis of obstructive sleep apnea in adult patients. Portable Monitoring Task Force of the American Academy of Sleep Medicine.

Based on a review of literature and consensus, the Portable Monitoring Task Force of the American Academy of Sleep Medicine (AASM) makes the following recommendations: unattended portable monitoring (PM) for the diagnosis of obstructive sleep apnea (OSA) should be performed only in conjunction with a comprehensive sleep evaluation. Clinical sleep evaluations using PM must be supervised by a practitioner with board certification in sleep medicine or an individual who fulfills the eligibility criteria for the sleep medicine certification examination. PM may be used as an alternative to polysomnography (PSG) for the diagnosis of OSA in patients with a high pretest probability of moderate to severe OSA. PM is not appropriate for the diagnosis of OSA in patients with significant comorbid medical conditions that may degrade the accuracy of PM. PM is not appropriate for the diagnostic evaluation of patients suspected of having comorbid sleep disorders. PM is not appropriate for general screening of asymptomatic populations. PM may be indicated for the diagnosis of OSA in patients for whom in-laboratory PSG is not possible by virtue of immobility, safety, or critical illness. PM may also be indicated to monitor the response to non-CPAP treatments for sleep apnea. At a minimum, PM must record airflow, respiratory effort, and blood oxygenation. The airflow, effort, and oximetric biosensors conventionally used for in-laboratory PSG should be used in PM. The Task Force recommends that PM testing be performed under the auspices of an AASM-accredited comprehensive sleep medicine program with written policies and procedures. An experienced sleep technologist/technician must apply the sensors or directly educate patients in sensor application. The PM device must allow for display of raw data with the capability of manual scoring or editing of automated scoring by a qualified sleep technician/technologist. A board certified sleep specialist, or an individual who fulfills the eligibility criteria for the sleep medicine certification examination, must review the raw data from PM using scoring criteria consistent with current published AASM standards. Under the conditions specified above, PM may be used for unattended studies in the patient's home. Afollow-up visit to review test results should be performed for all patients undergoing PM. Negative or technically inadequate PM tests in patients with a high pretest probability of moderate to severe OSA should prompt in-laboratory polysomnography.

Use of selective serotonin reuptake inhibitors and sleep disturbances in community-dwelling older women.

OBJECTIVES: To determine the association between use of selective serotonin reuptake inhibitors (SSRIs) and objective measures of sleep disturbances in older community-dwelling women, including women without evidence of depression. DESIGN: Cross-sectional study. SETTING: Four U.S. clinical centers. PARTICIPANTS: Two thousand eight hundred fifty-three women aged 71 and older (2,630 nonusers of antidepressants and 223 taking SSRIs alone, not in combination with other antidepressants). MEASUREMENTS: Medication use, assessed using an interviewer-administered questionnaire with verification of use from medication containers and computerized dictionary used to categorize type of medication; evidence of depression assessed using self-report or a score of 6 or higher on the Geriatric Depression Scale; and sleep parameters measured using a wrist actigraph, with data collected for an average of four consecutive 24-hour periods. RESULTS: Of the overall cohort of 2,853 women and of 2,337 women without evidence of depression, sleep disturbances were more common in women taking SSRIs than in those not taking antidepressants. After excluding women with evidence of depression and adjusting for multiple potential confounders, women taking SSRIs were more likely to have a sleep duration of 5 hours or less (multivariate odds ratio (MOR)=2.15, 95% confidence interval (CI)=1.04-4.47), sleep efficiency less than 70% (MOR=2.37, 95% CI=1.32-4.25), sleep latency of 1 hour or more (MOR=3.99, 95% CI=2.29-6.96) and eight or more long wake episodes (MOR=1.75, 95% CI=0.99-3.10). CONCLUSION: SSRI use by older women, including those without evidence of depression, is associated with a greater likelihood of sleep disturbances, including poorer sleep efficiency, longer sleep latency, and sleep fragmentation, manifested by multiple long wake episodes. These results add to the uncertainty regarding risks and benefits of SSRI use in aged populations.

Physical examination: Mallampati score as an independent predictor of obstructive sleep apnea.

STUDY OBJECTIVE: To assess the clinical usefulness of the Mallampati score in patients with obstructive sleep apnea. Mallampati scoring of the orophyarynx is a simple noninvasive method used to assess the difficulty of endotracheal intubation, but its clinical usefulness has not been validated in patients with sleep-disordered breathing. DESIGN: Prospective multivariate assessment of a predictor variable. SETTING: The UCSF Sleep Disorders Center. PATIENTS OR PARTICIPANTS: One hundred thirty-seven adult patients who were evaluated for possible obstructive sleep apnea. INTERVENTIONS: Prospective determination of the Mallampati score, assessment of other variables for multivariate analysis, and subsequent overnight polysomnography. MEASUREMENTS AND RESULTS: The Mallampati score was an independent predictor of both the presence and severity of obstructive sleep apnea. On average, for every 1-point increase in the Mallampati score, the odds of having obstructive sleep apnea (apnea-hypopnea index> or = 5) increased more than 2-fold (odds ratio [per 1-point increase] = 2.5; 95% confidence interval: 1.2-5.0; p = .01), and the apnea-hypopnea index increased by more than 5 events per hour (coefficient = 5.2; 95% confidence interval: 0.2-10; p = .04). These results were independent of more than 30 variables that reflected airway anatomy, body habitus, symptoms, and medical history. CONCLUSION: Our results indicate that Mallampati scoring is a useful part of the physical examination of patients prior to polysomnography. The independent association between Mallampati score and presence and severity of obstructive sleep apnea suggests that this scoring system will have practical value in clinical settings and prospective studies of sleep-disordered breathing.

Prevalence and correlates of periodic limb movements in older women.

STUDY OBJECTIVES: Periodic limb movements of sleep (PLMS) are common in the elderly. However, no large polysomnographic study has closely examined the relationship of PLMS to sleep architecture and arousals from sleep. We investigated the prevalence and correlates of PLMS in a community-based sample of older women. DESIGN: Observational study, cross-sectional analyses. SETTING: Two clinical sites participating in the Study of Osteoporotic Fractures (SOF). PARTICIPANTS: 455 older community-dwelling women (mean age 82.9 years) who completed in-home polysomnography at SOF visit 8. INTERVENTIONS: N/A. MEASUREMENTS AND RESULTS: In-home 12 channel polysomnography was performed with measurement of leg movements by bilateral piezo sensors. Measures of PLMS included the number of leg movements per hour of sleep (PLMI) and the number of leg movements causing EEG-documented arousals per hour of sleep (PLMA). An elevated PLMI was common, with 66% showing PLMI > or =5 and 52% showing PLMI > or =15. A PLMA > or =5 and > or =15 were observed in 124 (27%) and 26 (6%) participants respectively. After adjustment for the potential confounders of antidepressant medication use, age, race, body mass index, and apnea-hypopnea index, participants with a higher PLMA had a significantly higher arousal index, lower sleep efficiency, higher percentages of sleep stages 1 and 2 and lower percentages of stages 3-4 and REM (p < .001). An increased PLMI was associated with a higher arousal index, but not with other indices of sleep quality. Neither PLMI or PMLA was associated with subjective sleepiness or other known comorbidities. CONCLUSIONS: Periodic leg movements are very common in older community-dwelling women. PLMS which were associated with EEG arousals had a strong and consistent association with markers of disturbed sleep. PLMS associated with arousals thus appear to be more clinically relevant and should be considered when examining health outcomes associated with PLMS.

Oral nonprescription treatment for insomnia: an evaluation of products with limited evidence.

PURPOSE: To evaluate the level of evidence regarding the safety and efficacy of nonprescription therapies used for insomnia. REVIEWERS: Members of the American Academy of Sleep Medicine's Clinical Practice Review Committee. METHODS: A search of the World Wide Web was conducted using the terms insomnia, herbal remedies, and alternative treatments to develop a list of therapies. Therapies in this review include passionflower, valerian, Jamaican dogwood, hops, California poppy, chamomile, lemon balm, St. John's wort, kava kava, wild lettuce, scullcap, Patrinia root, first-generation histamine-1-receptor antagonists, alcohol, calcium, vitamin A, nicotinamide, magnesium, vitamin B12, I-tryptophan, 5-hydroxytryptophan, dietary changes, Natrum muriaticum, and Yoku-kan-san-ka-chimpi-hange. A search of the PubMed database was conducted in October 2002 using MeSH terms insomnia and each product listed in this paper, including only articles published in English between 1980 and 2002. Additional relevant articles from reference lists were also reviewed. Given the paucity of pediatric publications, this age group was excluded from this review. RESULTS AND CONCLUSIONS: Although randomized, placebo-controlled studies were available for a few compounds, rigorous scientific data supporting a beneficial effect were not found for the majority of herbal supplements, dietary changes, and other nutritional supplements popularly used for treating insomnia symptoms. Nevertheless, such treatments are described as alternative remedies for insomnia. Studies are limited by small numbers of participants and, in some instances, inadequate design, lack of statistical analysis, and sparse use of objective measurements. Sparse or no scientific data were found to support the efficacy of most products as hypnotics, including chamomile and St. John's wort. There is preliminary but conflicting evidence suggesting Valerian officinalis L. and first-generation histamine-1-receptor antagonists have efficacy as mild hypnotics over short-term use. There are significant potential risks associated with the use of Jamaican dogwood, kava kava, alcohol, and I-tryptophan. Physicians may find this information useful in counseling their patients.

Hypothermia from prolonged immersion: biophysical parameters of a survivor.

We report a case of survival following prolonged immersion and hypothermia. The patient survived for over 9 h in open water, after his vessel capsized and sank in the Pacific Ocean off the coast of Northern California. Water temperature on the day of the sinking was 14.4 degrees C (58.0 degrees F). Although he did have adequate flotation, the patient did not wear a survival suit. On initial physical examination in the Emergency Department (ED), the patient's rectal temperature was 30.0 degrees C (86.0 degrees F). With active rewarming, his temperature returned to normal (37.0 degrees C (98.6 degrees F)) within 5 h. Body fat of the patient was 19.6%, near the 50th percentile for his age (19.0%). Surface/volume ratio of the patient (.0228 m(2)/L) was 19% smaller than a predicted average (.0282 m(2)/L). We believe that the patient's large body habitus contributed to survival and that surface/volume ratio was likely the biophysical variable most closely associated with decreased cooling.