Effects of Cannabis on Multiple Visual Parameters and Self-Perceived Eyesight: A Cross-Sectional Study in Cannabis Users in Morocco

Cannabis is one of the most common intoxicants used worldwide. Cannabis is widely consumed worldwide and can lead to visual alterations. However, most of the available information on its effects comes from studies conducted in developed countries, while data remain limited in developing regions such as Morocco, despite its significant role in cannabis cultivation. The aim of this study was to explore multiple visual parameters and self-perceived eyesight in cannabis users in Morocco. A cross-sectional study was conducted between March 2022 and April 2023 in Marrakesh, Morocco, in cannabis consumers. Data collection was performed in two phases. First a hetero-administrated questionnaire was used to collect socio-demographics, intoxicant consumption habit information, and eye health information. Then, several visual acuity tests were performed, including a preliminary examination, a visual function assessment, and an eye health assessment. Ninety-five cannabis users participated in this study. The majority were single (62.1%) males (87.4%). All lived in the Marrakesh-Safi region (100%), and most had daily activities such as having a job or being a student (77.9%). Most had vision conditions like astigmatism or myopia (83.4%). The majority had multiple addictions (66.5%), mainly to tobacco (43.7%). Hashish was the main cannabis type used (57.9%), and smoked cannabis was the principal mode of consumption (94.7%). Many had a family history of cannabis addiction (58.9%). Day light sensitivity (66.3%) and appearance of eye symptoms after cannabis use (90.5%) were declared by the majority. In most cases, no impact on far or near vision or vision impairment due to cannabis use were declared. Our results showed that using cannabis could have significant adverse effects on visual functions.