Cannabis Use Linked to Slightly Lower Risk of Post-Retinal Detachment Complications: JAMA
A retrospective cohort study has revealed that patients using cannabis after retinal detachment repair had a reduced risk of developing proliferative vitreoretinopathy (PVR) and needing complex reoperations. However, the absolute risk reduction was modest (~2%). Researchers suggest anti-inflammatory properties of cannabis may contribute to the observed benefits. The study was published in JAMA by Ahmed M. and fellow researchers.
This retrospective cohort study used data from February 1, 2005, to February 1, 2025, drawn from a multicenter electronic health record network. The population was adult patients who had initial RD repair by PPV with or without SB, primary SB, or pneumatic retinopexy. The two groups were contrasted: one with confirmed cannabis-related disorder through medical records and testing by urine or blood, and a matched control group who had no history of cannabis use. Exclusion criteria of note were a prior diagnosis of proliferative diabetic retinopathy and follow-up for fewer than 6 months.
Patients were matched by propensity score techniques, which left 1,193 in each cohort. The mean age of the participants was 53.2 years (±16.1), of whom 69.7% were male (n=1,662) and 26.9% female (n=641). The main exposures assessed were recorded cannabis use and the nature of RD repair undertaken. The main outcomes monitored were PVR incidence and subsequent complex retinal repair at 6 months and 1 year postoperation. Cox regression analyses were applied to analyze the outcomes.
Key Findings
At 6 months after surgery, patients with cannabis use showed a statistically significant reduction in the risk of developing PVR (25 events, 2.10%) compared to non-users (52 events, 4.36%), with a relative risk (RR) of 0.48 (95% CI: 0.30–0.77; P = 0.002).
They also required fewer complicated RD repair surgeries (37 events, 3.10%) compared to the control group (60 events, 5.03%), with an RR of 0.62 (95% CI: 0.41–0.92; P = 0.02). These protective tendencies persisted through the 1-year follow-up.
Cannabis chemicals, especially cannabinoids, have been reported to possess anti-inflammatory and neuroprotective actions, which can theoretically regulate the fibrotic mechanisms that lead to PVR.
The large matched cohort study discovered that patients who underwent primary repair of retinal detachment and had recorded cannabis use were less likely to develop PVR and need advanced retinal surgery than those with no cannabis use. Although absolute outcome differences were small, the results justify further research on cannabis-related mechanisms in ocular fibrosis and retinal recovery. If confirmed in controlled trials, this may result in novel prevention strategies for PVR, a disease that has no very effective prophylaxis at present.
Reference:
Alshaikhsalama AM, Alsoudi AF, Mukhtar A, et al. Long-Term Cannabis Use and Risk of Postoperative Proliferative Vitreoretinopathy. JAMA Ophthalmol. Published online July 03, 2025. doi:10.1001/jamaophthalmol.2025.1851
