Heart rate response to cannabis in active older adults

PURPOSE: Cannabis use is increasing among older adults. Given reported associations between delta-9-tetrahydrocannabinol (THC) and increased acute heart rate, there is concern regarding the impact of cannabis on cardiovascular health in older adults. Engaging in regular physical activity (PA) is associated with reduced heart rate and cardiovascular disease risk, but it has yet to be explored whether PA status influences the acute effects of THC on heart rate in older adults. METHODS: This data is from a larger observational study of older adults using cannabis for sleep, pain, or mood problems. Based on participants’ self-report Leisure-Time Activity Categorical (L-Cat) responses, they were grouped into high, moderate, or low PA groups. Participant heart rate was measured pre- and 2 h post edible cannabis consumption. Self-reported THC dose (mg) was recorded, and blood THC was assessed pre- and 2 h post-consumption. RESULTS: Two separate ANOVA models, controlling for age, assessed interactions between L-Cat group and blood or self-reported THC on change in heart rate pre- to post-use. The L-Cat group x self-reported THC interaction was not significant, but the L-Cat group x blood THC interaction was (F(2,202) = 6.45, partial η2 = 0.06, p = 0.002) such that higher blood THC was associated with a greater increase in heart rate, an effect most pronounced in the low PA group. CONCLUSION: These results align with previous research where THC is associated with higher heart rate but provide novel insight as to the potential protective effects of high levels of PA in older adults. CLINICAL TRIAL REGISTRATION: The study was pre-registered on Clinicaltrials.gov (NCT05188404).