Comparison of Temazepam and Acetazolamide to Treat Difficulty Sleeping at High Altitude

Difficulty sleeping is very common with acute high altitude exposure. Sleep disturbances were reported by more than 70% of participants in acute mountain sickness pharmacologic treatment trials. Difficulty sleeping is one of the primary complaints of visitors to high altitude and some authors consider difficulty sleeping to be nearly universal at high altitudes. Acetazolamide, temazepam, zolpidem and zaleplon are all effective and safe in treating the acute insomnia of high altitude. No head-to-head trials have been performed to determine the best drug class for treatment of high altitude sleep disturbances. The purpose of this study is to compare temazepam and acetazolamide in the treatment of high altitude sleep disturbances. Such knowledge will benefit the hundreds of thousands of visitors to areas of high altitude throughout the world.

The study will be a convenience sample of 100 trekkers in Manang, Nepal (elevation 11,500 feet). The study will only enroll trekkers who have gained more than 200 meters (650 feet) over the preceding 24 hours. Subject enrollment will take place from March 1, 2012, through May 30, 2012. One hundred subjects will be enrolled.

All subjects will complete the study in Manang, Nepal. Once an individual decides to enroll in the study, they will be instructed on the risks of the study and informed consent will be obtained. Eligibility to participate will be verified.

Each subject will be randomly assigned to take 125 mg of acetazolamide or 7.5 mg of temazepam by mouth immediately prior to going to bed. Each subject will only take one dose of the medication as part of the trial. Subjects will wear a pulse oximeter and an actigraph to bed. An actigraph is an accelerometer that is worn like a wrist watch. Actigraphs can sense and record movement and for this reason are often used in sleep studies to help measure sleep duration and quality.

Study participants will keep a sleep log and will be asked to complete a Groningen Sleep Quality Questionnaire Survey and Lake Louise Acute Mountain Sickness questionnaire. Subjects will also complete a Stanford Sleepiness Scale every hour for eight hours.

Through both objective and subjective measurement of sleep quality, this study is designed to determine which medication is associated with improved sleep at high altitude.

Inclusion criteria

• Trekkers on the Annapurna circuit
• Must be in the process of ascent (> 200 meters over the previous 24 hours)
• Must be willing to stay 2 nights in Manang, Nepal
• Healthy adults, age 18-65
• Self-report of new difficulty sleeping over the previous two days

Exclusion criteria

• Recent (< 2 weeks) high altitude exposure (higher than 11, 500 feet or 3500 meters)
• Current acute illness
• Moderate to Severe Acute Mountain Sickness (Lake Louise AMS score > 4)
• High Altitude Cerebral Edema
• High Altitude Pulmonary Edema
• Any pre-existing sleep disorders or sleep related condition including obstructive sleep apnea, morbid obesity (BMI > 40), restless leg syndrome, etc.
• Any lung disease or condition affecting the lungs, including chronic obstructive pulmonary disease, asthma, cystic fibrosis, etc.
• Congestive heart failure, pulmonary hypertension, or cardiomyopathy
• Current oxygen use
• Kidney disease
• Liver disease
• Pregnancy or breast feeding
• Seizure disorder or other neurologic disorder
• Glaucoma
• Sulfa allergy
• Acetazolamide allergy
• Benzodiazepine allergy
• Temazepam allergy
• Currently on acetazolamide
• Currently taking any benzodiazepines
• Current medical treatment with any of the following: antidepressants, neuroleptics, anxiolytics, H1 antihistamines, barbiturates or hypnotics (including benzodiazepines or any other sleep aids).
• Major psychiatric diagnosis (depression, anxiety, schizophrenia)
• Recreational drug use
• Caffeine con¬sumption > 3 cups of coffee/day
• Alcohol consumption > 1 drink/day
• Mental Retardation or Developmental Disabilities
• Inability to provide informed consent