Long-term Cortisol Levels Research Articles

Long-Term Benzodiazepine Use and Salivary Cortisol

As benzodiazepines (BZDs) have anxiolytic effects, it is expected that they influence the stress system. During short-term treatment, BZD use was found to suppress cortisol levels. However, little research has been done on the effects of long-term BZD administration on the hypothalamic-pituitary-adrenal (HPA) axis. The association between long-term BZD use and cortisol levels was investigated in subjects of the Netherlands Study of Depression and Anxiety with a lifetime diagnosis of anxiety or depression (n = 1531). The subjects were categorized as "daily BZD users" (n = 96), "infrequent BZD users" (n = 172), and "nonusers" (n = 1263). Possible associations between characteristics of BZD use (dose, duration, and dependence) and salivary cortisol levels were analyzed. Subjects provided 7 saliva samples, from which 4 cortisol indicators were calculated: the cortisol awakening response, diurnal slope, evening cortisol, and cortisol suppression after ingestion of 0.5 mg of dexamethasone. Daily users used BZDs for a median duration of 26.5 months and had a median daily dosage of 6.0 mg as measured in diazepam equivalents. Evening cortisol levels were significantly lower in daily users (P = 0.004; effect size: d = 0.24) and infrequent users (P = 0.04; effect size: d = 0.12) compared to nonusers. We did not find significant differences in the cortisol awakening response, diurnal slope, or in the dexamethasone suppression test. Despite the finding of slightly lower evening cortisol levels in daily and infrequent BZD users compared to nonusers, results indicate that long-term BZD use is not convincingly associated with HPA axis alterations.

Overview: toward a dysregulation hypothesis of depression.

The authors suggest that the activity of neurotransmitter systems in the affective disorders and related psychiatric syndromes may be better understood as a reflection of a relative failure in their regulation, rather than as simple increases or decreases in their activity. A model organized around the concept of "dysregulation" posits that persistent impairment in one or more neurotransmitter homeostatic regulatory mechanisms confers a trait vulnerability to unstable or erratic neurotransmitter output. Evidence from clinical and animal model studies for dysregulation of the noradrenergic system in depression is examined with respect to criteria generated by such a general model, and a specific configuration of noradrenergic dysregulation in some forms of depression is proposed.