Cannabidiol and vitamin E on blood flow in the brain of older adults

The objective of this research is to investigate the effects of cannabidiol and vitamin E on cerebrovascular function and cognition in middle-aged to older adults. This will be a randomised, double-blind, placebo-controlled trial. We will aim to recruit 80 participants for this study. Recruitment will occur via an approved media release that incorporates physical advertisement, social media and information on the UniSQ website. The individuals will be recruited from in and around Darling Downs, South-West and West Moreton regions, the regions comprising south-east of Queensland, and the Northern New South Wales regions of Australia. Respondents will initially be screened for suitability using a medical history questionnaire to determine whether participants meet the inclusion and/or exclusion criteria. Once participants are recruited, voluntary written informed consent will be obtained prior to any assessment being performed and their allocation to one of the four arms of the study. The four arms of this study will consist of: A control group, which will be requested to take two placebo capsules (maltodextrin filler, taken orally) each evening, continuously for 16 weeks. A second arm (the cannabidiol group) that will be requested to take one 150mg cannabidiol oral capsule and one placebo capsule each evening, continuously for 16 weeks. A third arm (the vitamin E group) that will be requested to take one 400IU vitamin E oral capsule and one placebo capsule each evening, continuously for 16 weeks. A fourth arm (the combination group) that will be requested to take one 150mg cannabidiol oral capsule and one 400IU vitamin E oral capsule each evening, continuously for 16 weeks. Participants will be requested to record the time they consume their capsules in a participant diary provided. The study investigator will follow-up with participants via a telephone call every two weeks to check wellbeing and compliance. Any unused capsules will be returned at the end of the intervention and counted to demonstrate compliance. Once informed about the study and its requirements (by providing potential participants with a participant information sheet), participants that meet the inclusion criteria, and who voluntarily provide written informed consent, will be screened. Once screened and if still eligible, participants will undergo testing at UniSQ Ipswich or UniSQ Toowoomba. The baseline and follow-up visits will incorporate the following methods: Cerebrovascular responsiveness to hypercapnia (participant will breathe a 5% carbon dioxide gas for approximately 3 minutes) and cognitive stimuli (participant will complete a series of cognitive tasks from the NIH Toolbox and the Trail Making Task) using transcranial Doppler sonography; Profile of Mood States to ascertain current mood; EQ-5D-5L Quality of Life questionnaire; Anthropometry, determined by body weight and height (body mass index calculation), waist and hip circumferences (waist:hip ratio calculation) and Dual-energy X-ray absorptiometry (DEXA) which will ascertain body composition of total fat mass, lean mass, body fat percentage, and bone mineral content and density; Systolic and diastolic blood pressure and arterial elasticity will be measured non-invasively using a Research Cardiovascular Profiling System; Biomarker analyses after blood is collected; and Exercise capacity will be assessed using a 6 minute walk test, a 30-second sit-to-stand test, and handgrip strength will be determined using hand dynamometry.