Insomnia and Benzodiazepine Dependency among Older Adults

Philippe Voyer, RN, PhD, Associate Professor, Faculty of Nursing, Laval University; Researcher, Laval University Geriatric Research Unit,St-Sacrement Hospital, Quebec, QC.
Michel Préville, MD, Associate Professor, Faculty of Medicine, Université de Sherbrooke; Researcher, Research Centre on Aging, Sherbrooke Geriatric University Institute, Sherbrooke, QC.
and Researchers of the Étude sur la santé des aînés team.

Sleep complaints by older adults constitute a very common situation faced by health care providers. However, not all professionals respond to the complaint the same way. Some will briefly assess the complaint and resort rather quickly to medication while others will assess the complaint carefully in order to exclude the diagnosis of primary insomnia and prescribe alternative interventions to improve sleep. When medicine is prescribed, the type of compound often selected is benzodiazepine. However, benzodiazepine carries a significant risk of adverse reaction, including drug dependency, both of which are clinical problems that should not be underrated, especially when treating a subjective complaint and not a specific diagnosis.
Key words: insomnia, benzodiazepine, dependency, addiction, older adults.

Sleep complaints are frequent among older people. Sleep-related problems affect nearly 50% of community-dwelling older adults.1 Diagnostic criteria for primary insomnia include a reduction in the duration, quality, or efficacy of sleep. There may be difficulty in getting to sleep at the beginning of the night, difficulty in staying asleep through the night, or premature awakening in the morning coupled with inability to fall back asleep, associated with significant distress or impairment of daytime functioning due to poor quality of sleep.2 Primary insomnia disorder is less common than sleep complaints and pharmacological intervention should be reserved to the former.

Insomnia and Aging
Change brought by the normal effects of aging should not be confused with a pathological sleep pattern. With aging there are alterations in the circadian rhythm, which result from an age-related loss of neurons and decreased dendritic connections, causing sleep to be distributed throughout the 24-hour day instead of being concentrated at night. Compared to younger adults, older individuals generally spend more time in bed but less time asleep, wake more often and remain awake for longer periods, and have less effective sleep.3 Sometimes age-related sleep changes are misinterpreted, which may lead to unneeded pharmacological treatment. This is the first pitfall to be avoided in the management of sleep disturbance among older adults.

Treatment of Insomnia with Benzodiazepines
Benzodiazepines (BZDs) are indicated for short-term treatment of primary insomnia. After 30 days of continuous use of BZD to treat insomnia, the drug’s effectiveness is either not superior to that of a placebo4 or it remains unknown.5 Although evidence has shown that BZD can improve sleep quality, it may also lead to adverse drug reactions.4

Because of altered pharmacodynamics (heightened reaction to BZD effect) and the pharmacokinetics related to aging (mainly distribution, metabolism and elimination), older individuals are especially prone to adverse drug reactions. Benzodiazepine medication may induce drowsiness, psychomotor slowing, cognitive impairment, forgetfulness, morning hangover effect, and ataxia. Furthermore, since older adults frequently use BZDs over a long period, they may be at particular risk for dependence. According to the conclusions of a meta-analysis among older adults,6 the benefits of BZDs in treating insomnia may not outweigh the associated increased risk, especially if the patient has additional risk factors for cognitive or psychomotor adverse events. On the other hand, for short-term treatment (less than 30 days), there is a strong rationale to support BZD use. Its use for longer than 30 days is much more debatable.

Long-term Use of Benzodiazepines and Drug Dependency
Not only is the long-term use of BZD not effective