Insomnia and Daytime Function in Osteoarthritis

To assess the efficacy and safety of zolpidem at doses up to 10 mg compared to placebo in patients with insomnia associated with osteoarthritis


Eligibility Criteria:
Inclusion Criteria:

* Patients that are male or female aged 45 years or older.
* Patients having given their written informed consent prior to participating in the trial.
* Patients who have had OA of the knee or hip for at least 6 months, as diagnosed using the American College of Rheumatology Classification Criteria for Osteoarthritis.
* Patients who, based on historical data, developed insomnia together with or after development of arthritic symptoms and presently have difficulty in maintaining sleep or have non-restorative sleep for at least three months preceding study entry and have difficulties with daytime activities because of problems with sleeping.
* Patients who, based on historical data, experience sleep disturbance at least 3 nights per week.
* Patients must have a score of greater than 1 on the Likert Pain Scale within two weeks of study participation while taking pain medication
* Patients must have been on a stable dosing regimen of analgesic/anti-inflammatory medication for one month prior to study entry and agree to maintain the dose throughout the study. Patient must agree not to exceed 4000 mg (i.e., 1000 mg acetaminophen, 4 times per day) as rescue medication in case of unexpected arthritis pain. Acetaminophen is the only rescue medication allowed in addition to the patient's stable dosing regimen.

Exclusion Criteria:

* Female patients that are pregnant or are breast-feeding.
* Patients with reproductive potential not implementing adequate contraceptive measures.
* Patients with mental disorders or who cannot be relied upon to understand the trial requirements and comply with the treatment regimen.
* Patients that are shift workers or have required a change in their regular sleep schedule by at least three hours within the last three months.
* Patients that have been treated for insomnia within 2 years prior to the onset of osteoarthritis.
* Patients that have a history of recurrent major depressive disorder over the last 3 years or any single episode of major depression over the last 2 years.
* Patients having a history of seizures or other significant neurological diseases.
* Patients with a history of myasthenia gravis.
* Patients that have had serious head injury within the past 10 years.
* Patients with insulin dependent diabetes poorly controlled in the opinion of the investigator.
* Patients who have had a stroke or myocardial infarction in the 6 months before the screening visit.
* Patients with unstable angina or severe heart failure.
* Patients with a history of significant impairment of any organ system that could impair the ability of the patient to participate in the study.
* Patients with abnormal clinical laboratory tests judged by the Investigator to require clinical intervention.
* Patients that fail to complete at least 3 of 7 consecutive nights and days (day must follow night to be consecutive) on their Evening and Morning Questionnaires during the screening period and have not satisfied the following:

  1. scored 2 or greater on the Evening Questionnaire, AND
  2. Slept a total of less than 6 hours, as determined by:

a Wake Time after Sleep Onset of greater than 1 hour, and/or having time to fall asleep (sleep latency) of 45 minutes or greater.

* Patients that have used any drug (e.g. beta-blockers, antihistamines) and subsequently reported significant CNS side effects.
* Patients with a history of hypersensitivity/exaggerated drug response to sedative/hypnotic drugs (allergic or paradoxical), including zolpidem.
* Patients with a history of sleep apnea or current signs/symptoms associated with sleep apnea
* Patients with a history of symptoms compatible with diagnosis of periodic leg movement or restless legs syndrome.
* Patients with a history of cancer within the last 5 years or that have suspected neoplastic disease (with the exception of nonmelanomatous skin cancer).
* Patients that are taking any drugs of abuse or psychotropic drugs (including, but not limited to antidepressants, antipsychotics, or anxiolytics) or drugs with demonstrated effects on sleep-wake function (including, but not limited to herbal supplements, diphenhydramine, and theophylline).
* Patients that have used over-the-counter sleep medication within seven days prior to study entry. Prescription sleep medications must have been discontinued at least 7-25 days prior to study entry, depending upon the half-life of the particular compound.
* Patients who have taken investigational drugs within 30 days of the screening visit.