A longitudinal psychometric evaluation of a context-sensitive positive health questionnaire for measuring broad health in Dutch adults.

Management of inflammatory bowel disease (IBD), including its most common forms—Crohn’s disease and ulcerative colitis—typically involves a combination of medication, lifestyle modifications, and surgery. (Rubin et al. ; Lichtenstein et al. ) The goal of a clinical remission is only achieved for a subset of patients over the lifetime disease course, (Rubin et al. ; Lichtenstein et al. ; Danese et al. ) emphasizing the need for new treatment modalities. Recent surveys suggest that 12–38% percent of patients with IBD use cannabis in countries with legal access, with more than half reporting use to relieve their IBD-related symptoms. (Lal et al. ; Velez-Santiago et al. ) Pre-clinical research has demonstrated that certain cannabinoids (including those contained in the cannabis plant) activate cannabinoid receptor (CBR) 1, which decreases release of acetylcholine, reducing gut motility, and downregulates transient receptor potential vanilloid 1 (TRPV1), potentially alleviating visceral pain. (Pesce et al. ; Landi et al. ; Esfandyari et al. ; Hong et al. ) CBR 2 agonists, including cannabidiol and fatty acid amide hydrolase (FAAH) reduce colonic inflammation in animal studies, further suggesting therapeutic potential of cannabis for IBD. (Couch et al. ). Several systematic reviews have evaluated the role of cannabis and cannabinoids in the treatment of patients with IBD and reported mixed findings. Two Cochrane systematic reviews of randomized trials in patients with ulcerative colitis and Crohn’s disease concluded that effectiveness remains uncertain. (Kafil et al. a; b) A subsequent systematic review including both trials and non-randomized studies reported no evidence of improvements in clinical remission or reduced inflammation, though noted improvements in patient-reported symptoms and quality of life. (Doeve et al. ) Both reviews relied on studies with small sample sizes, high potential for biases, and did not include several recently published studies. (Naftali et al. ; Coates et al. ) Three systematic reviews incorporating more recent studies collectively support that cannabis can improve quality of life in patients with Crohn’s disease, or ulcerative colitis, yet had conflicting results regarding cannabis impact on disease activity and remission. (Kumar ; Kumar et al. ; Kang et al. ) No recent reviews include non-interventional studies, examined patient reported outcomes beyond quality of life, such as pain or daily functioning, or focused on non-FDA approved cannabis products. In the light of these conflicting findings, the inclusion of non-interventional studies, alongside evidence on additional patient reported outcomes from randomized clinical trials could provide valuable real-world insights into the effectiveness of cannabis in treating patients with IBD. Providing a comprehensive synthesis of current evidence is critical to quantify cannabis risk–benefit, especially in chronic use, among the growing population of IBD patients who are seeking symptom relief. (Lal et al. ; Velez-Santiago et al. ; Hilton Boon et al. ; Pratt et al. ) Therefore, we aimed to summarize and critically evaluate evidence from controlled non-interventional studies and controlled interventional trials on the effectiveness of THC-containing cannabis in patients with IBD.