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Published on: June 18, 2014
Is peri-operative cortisol secretion related to post-operative cognitive dysfunction?
L S Rasmussen1, J T O'Brien, J H Silverstein
1Department of Anaesthesia, Centre of Head and Orthopaedics, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark.
Post-operative cognitive dysfunction (POCD) is linked to altered cortisol patterns after surgery. Flattening of the diurnal cortisol rhythm, indicated by reduced morning/afternoon ratios, is significantly associated with POCD development.
Area of Science:
- Endocrinology
- Neuroscience
- Geriatric Medicine
Background:
- Surgery significantly impacts cortisol secretion patterns.
- Cortisol's neurotoxic potential suggests a role in post-operative cognitive dysfunction (POCD).
- Hypothesis: POCD incidence correlates with cortisol level alterations.
Purpose of the Study:
- To investigate the relationship between cortisol secretion patterns and POCD incidence.
- To assess the impact of surgery on diurnal cortisol variation.
- To determine if altered cortisol rhythms predict cognitive decline post-surgery.
Main Methods:
- 187 patients over 60 undergoing major non-cardiac surgery were studied.
- Salivary cortisol levels measured pre- and post-operatively (1 day, 7 days, 3 months).
- Cognitive function assessed using neuropsychological tests; POCD defined by a Z score > 1.96.
Main Results:
- Salivary cortisol concentrations significantly increased post-surgery.
- POCD detected in 18.8% at 1 week and 15.2% at 3 months.
- A persistent flattening of the diurnal cortisol (am/pm) ratio post-operatively was significantly related to POCD at 1 week.
Conclusions:
- Diurnal cortisol variation patterns are significantly related to POCD.
- Circadian rhythm disturbance or metabolic endocrine stress may drive post-surgical cognitive dysfunction.
- Altered cortisol secretion is a potential mechanism underlying POCD.
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