"Our results show dronabinol is an effective treatment for behavioral agitation in patients with Alzheimer's and may ultimately help reduce the stress often experienced by caregivers," said geriatrician Joel S. Ross, M.D. a member of the teaching faculty at Monmouth Medical Center and the lead investigator in the study. "While difficult for the patient, the effects of agitation can greatly impact the emotional and physical health of family members and caregivers. By reducing patients' agitation, caregivers are able to focus more time and energy on their patients' overall wellbeing."
Dronabinol, marketed as Marinol, is synthetic delta-9-tetrahydrocannabinol (delta-9-THC). Delta-9-THC also is a naturally occurring component of Cannabis sativa L (marijuana). Dronabinol has been approved by the U.S. Food and Drug Administration (FDA) for the treatment of anorexia in patients with HIV/AIDS and for the treatment of nausea and vomiting associated with cancer chemotherapy. Recent clinical tests also have examined dronabinol's potential to relieve symptoms of multiple sclerosis.1
Agitation is the most common behavioral management problem in patients with Alzheimer's and affects an estimated 75 percent of people with the disease. It may lead to a variety of symptoms ranging from physical and/or verbal abusive postures, physically non-aggressive conduct including pacing and restlessness, as well as verbally disturbed behaviors such as screaming and repetitive requests for attention.
More than 80 percent of caregivers report they frequently experience high levels of stress, and nearly half say they suffer from depression, according to the Alzheimer's Association.
The Phase II, open label, randomized, parallel-group study involved 54 community-dwelling patients at two sites, all who demonstrated behavioral agitation (mean age = 81). All patients were over the age of 50 years and met DSM-IV criteria for dementia related to Alzheimer's. The Mini-Mental State Exam (MMSE) and the Cohen-Mansfield Agitation Inventory (CMAI) were used to measure severity of Alzheimer's disease and agitation level, respectively. Following a one-week qualifying period to evaluate the degree of agitation, patients were screened on Day 0, evenly randomized to one of two treatment groups (dronabinol 2.5 mg bid or dronabinol 5 mg bid) on Day 7, and returned for clinic visits on Day 21, Day 35 and Day 63. The primary efficacy measurement was the CMAI, a 38-item rating scale that evaluates the prevalence of pathological and disruptive behaviors. The secondary efficacy measurements were the Caregiver's Burden Inventory (CBI), CGI Severity of Alzheimer's disease (CGI-S AD), Instrumental Activities of Daily Living Scale (IADL) and MMSE. Evaluation at nine weeks found significant reductions of CMAI scores in both groups. There also was a trend toward a decrease in CBI scores and increase in IADL scores in both groups, without a statistical difference between the two doses. The 5 mg bid group experienced a trend toward a decrease in CGI-S AD scores.
Doses could be adjusted during the study, allowing for a patient to receive both doses of the medication and be included in both groups at the time of evaluation for efficacy and adverse events. Adverse events experienced by more the five percent of patients involved in the study included abnormal gait, accidental injury, agitation, anxiety, asthenia, dizziness, somnolence, spontaneous bone fracture and vomiting. Two deaths occurred in the patient population, but investigators determined both were unrelated to the medication.
Monmouth Medical Center, an affiliate of the Saint Barnabas Health Care System, is a 527-bed community teaching hospital located in Long Branch, NJ. For two decades, Monmouth Medical Center's geriatric program has been a recognized leader in the development of unique health care services for seniors. In 1982, a multidisciplinary geriatric team was established in response to the growing needs of older adults. Today, the Greenwall Geriatric Program at Monmouth coordinates health and social services for the elderly and their families in a community-teaching-hospital environment.
1Zajicek, J. The Lancet, Nov. 8, 2003: vol 263;pp 1517-1526.