Microvascular Health is Reduced in Frequent Cannabis Users

BACKGROUND: Microvascular dysfunction is a marker of endothelial vascular damage and is considered one of the earliest indicators of cardiovascular disease (CVD) development. Frequent cannabis use has been previously linked to increased CVD risk. However, whether microvascular health is impacted by cannabis use in otherwise healthy young adults has not been explored yet. PURPOSE: The purpose of this study was to investigate the impact of frequent cannabis usage on microvascular health in young healthy adults. METHODS: Thirteen frequent cannabis users (CU, 5 males and 8 females; age:23±3 yo; used cannabis 2.5±2 days/week) and thirteen demographical matched never users (NU, 5 males and 8 females; age:22±1 yo) completed a comprehensive assessment of microvascular function. Microvascular health was assessed using Laser Doppler Imaging coupled with Post Occlusive Reactive Hyperemia (PORH), to evaluate overall microvascular function, and Local Thermal Hyperemia (LTH) to evaluate neurogenic and endothelial mechanisms of vascular function. Blood flow was calculated as cutaneous vascular conductance, considering red blood cell flux and mean arterial blood pressure. RESULTS: Cannabis users exhibited significantly ( p=0.01) lower microvascular function when compared to never users (PORH, CU: 0.68±0.18 vs. NU: 0.85±0.14 mmHg/PU). Of note, microvascular function was significantly ( p=0.03) reduced in those that use cannabis more than 2.5 days/week (n=5; 0.55±0.10) when compared to those who used it less frequently (n=8; 0.76±0.18 mmHg/PU). In addition, neurogenic mechanisms (CU:1.31±0.57 vs. NU: 1.89±0.48 mmHg/PU; p=0.009) and endothelial mechanisms (CU: 1.61±0.44 vs. NU: 1.96±0.35 mmHg/PU; p=0.03) were significantly lower in cannabis users when compared to never users. CONCLUSIONS: Our results suggest that frequent cannabis users exhibit reduced microvascular health in comparison to never users, suggesting worse long-term CVD outcomes. Specifically, those that use cannabis more than 2 times per week exhibit lower microvascular function. In addition, cannabis use negatively impact neurogenic and endothelial microvascular mechanisms that warrant further investigation. This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.