Alzheimer’s disease: effects of aerobic training and cognitive stimulation on cortisol levels and behavioral disorders

Sundowning syndrome (SDS) in individuals with Alzheimer’s disease (AD) is a clinical phenomenon characterized by the intensification of neuropsychiatric symptoms during the sunset. Currently, there are no specific treatments for SDS, but recent literature reported a strong relationship between high levels of cortisol and SDS symptoms. Both aerobic training (AT) and cognitive stimulation (CS) are capable to reduce the level of cortisol. However, it is not clear if SDS symptoms would benefit from AT and CS. PORPUSE: To evaluate the effects of AT and CS as potential treatments of SDS. The combination effects of AT and CS (AT+CS) was also assessed. METHODS: Eighty patients with advanced AD (Clinical Dementia Rate CDR2) were randomly assigned to: CS group (n: 20, 86±9 yrs), which was treated with a cognitive stimulation; AT group (n: 20, 84±7 yrs), treated with aerobic training; CS+AT (n: 20, 85±8 yrs) group, which performed both AT and CS. All groups were compared with a control group of AD patients treated with standard pharmacological therapy: CTRL (n: 20, 84±10 yrs). All treatments were performed 5 days a week, for 2 months, one hour before the sunset. Salivary levels of cortisol were collected 5 times a day before and after treatments, together with behavioral disorders test (Neuropsychiatric Inventory (NPI)). RESULTS: After the training period, cortisol levels decreased significantly in AT -50% and CS+AT -50%, while at contrary was similar to baseline in CS and CTRL. Similarly, behavioral disorders reduced by ~50% in AT and CS+AT groups. Dates are summarized in table 1 (Tab.1). CONCLUSION: The main outcome of this study was that a program of AT or the combination of AT and CS decreased the salivary levels of cortisol. Interestingly, SDS symptoms also decreased to a similar extent in the same groups, suggesting a possible strengthening of this neuro-endocrinal pathway associated with these interventions, and suggested that AT and AT+CS as potential treatments of SDS.