The effects of flurazepam on sleep studies in patients with chronic obstructive pulmonary disease

Medication effects on sleep and breathing

Sleep respiration is regulated by circadian, endocrine, mechanical and chemical factors, and characterized by diminished ventilatory drive and changes in Pao2 and Paco2 thresholds. Hypoxemia and hypercapnia are more pronounced during rapid eye movement. Breathing is influenced by sleep stage and airway muscle tone. Patient factors include medical comorbidities and body habitus. Medications partially improve obstructive sleep apnea and stabilize periodic breathing at altitude. Potential adverse consequences of medications include precipitation or worsening of disorders. Risk factors for adverse medication effects include aging, medical disorders, and use of multiple medications that affect respiration.

WITHDRAWN: Benzodiazepines and related drugs for insomnia in palliative care

This review is out of date, and the original authors are no longer available to update it.

The editorial group responsible for this previously published document have withdrawn it from publication.

Benzodiazepines and related drugs for insomnia in palliative care

BACKGROUND

Insomnia, a subjective complaint of poor sleep and associated impairment in daytime function, is a common problem. Currently, benzodiazepines are the most used pharmacological treatment for this complaint. They are considered helpful for occasional short-term use up to four weeks but longer term use is not advised due to potential problems regarding tolerance, dosing escalation, psychological addiction and physical dependence. There is no consensus on their utility in patients with progressive incurable conditions who may require assistance with sleep for many weeks as their condition deteriorates.

OBJECTIVES

To assess the effectiveness and safety of benzodiazepines or benzodiazepine receptor agonists such as Zolpidem, Zopiclone and Zaleplon for insomnia in palliative care.

SEARCH STRATEGY

Several electronic databases were searched including Cochrane PaPaS Group specialized register, Cochrane Library Issue 4, 2001, MEDLINE, EMBASE, BNI plus, CINAHL, BIOLOGICAL ABSTRACTS, PSYCINFO, CANCERLIT, HEALTHSTAR, WEB OF SCIENCE, SIGLE, Dissertation Abstracts, ZETOC and the MetaRegister of ongoing trials. These were searched from 1960 to 2001 or as much of this range as possible. Additional articles were sought by handsearching reference lists in standard textbooks and reviews in the field and by contacting academic centres in palliative care and pharmaceutical companies. There were no language restrictions.

SELECTION CRITERIA

Studies considered for inclusion were randomized controlled trials of adult patients in any setting, receiving palliative care or suffering an incurable progressive medical condition. (For example, cancers, AIDS, Motor Neurone Disease, Multiple Sclerosis, Parkinson's Disease, Chronic Obstructive Pulmonary Disease). There had to be an explicit complaint of insomnia in study participants, diagnosed by any of the three main classification systems (DSM-IV (APA 1994), ICSD (AASD 1990) or ICD (WHO 1992)), or as described in the study if it involved a subjective complaint of poor sleep. Studies had to compare a benzodiazepine or Zolpidem or Zopiclone or Zaleplon with placebo or active control for the treatment of insomnia. Any duration of therapy were considered.

DATA COLLECTION AND ANALYSIS

Abstracts were independently inspected by both reviewers, full papers were obtained where necessary. Where there was uncertainty advice was sought by a third (PW). Data extraction and quality assessments were undertaken independently by both reviewers.

MAIN RESULTS

No randomized controlled trials were identified meeting the a priori inclusion criteria. Thirty-seven studies were considered but all were excluded from the review.

REVIEWER'S CONCLUSIONS

Despite a comprehensive search no evidence from randomized controlled trials was identified. It was not possible to draw any conclusions regarding the use of benzodiazepines in palliative care.

Obstructive lung disease and sleep

There is a significant interaction between obstructive lung disease and sleep--sleep is associated with clinical deterioration in obstructive lung disease, and vice versa. Knowledge of the pathophysiology of deterioration in obstructive lung disease during sleep is essential to the understanding of the management of this problem. Recent information has helped to clarify this pathophysiology and has led to more aggressive treatment for deterioration of obstructive lung disease during sleep. Whether this newer and more aggressive treatment strategy improves survival or morbidity in these conditions is a challenge for future research.

Benzodiazepines, breathing, and sleep

The benzodiazepines are sedative hypnotic drugs, i.e., central nervous system depressant drugs, that may adversely affect the control of ventilation during sleep. Prescription of these drugs may worsen sleep-related breathing disorders, especially in patients with chronic obstructive pulmonary disease or cardiac failure. The most frequent users of sedative hypnotics are the polymorbid elderly with a secondary complaint of insomnia. Although the benzodiazepines may reduce sleep fragmentation, their long-term use may also cause health problems, such as complete obstructive sleep apnea in heavy snorers or short repetitive central sleep apnea in patients with recent myocardial infarction. Since drugs of this class vary in their effects, it is crucial to note the action of a given benzodiazepine on the control of vital functions during sleep.