Cannabis-Based Products for Chronic Pain : A Systematic Review.

BACKGROUND: Contemporary data are needed about the utility of cannabinoids in chronic pain. PURPOSE: To evaluate the benefits and harms of cannabinoids for chronic pain. DATA SOURCES: Ovid MEDLINE, PsycINFO, EMBASE, the Cochrane Library, and Scopus to January 2022. STUDY SELECTION: English-language, randomized, placebo-controlled trials and cohort studies (≥1 month duration) of cannabinoids for chronic pain. DATA EXTRACTION: Data abstraction, risk of bias, and strength of evidence assessments were dually reviewed. Cannabinoids were categorized by THC-to-CBD ratio (high, comparable, or low) and source (synthetic, extract or purified, or whole plant). DATA SYNTHESIS: Eighteen randomized, placebo-controlled trials (n = 1740) and 7 cohort studies (n = 13 095) assessed cannabinoids. Studies were primarily short term (1 to 6 months); 56% enrolled patients with neuropathic pain, with 3% to 89% female patients. Synthetic products with high THC-to-CBD ratios (>98% THC) may be associated with moderate improvement in pain severity and response (≥30% improvement) and an increased risk for sedation and are probably associated with a large increased risk for dizziness. Extracted products with high THC-to-CBD ratios (range, 3:1 to 47:1) may be associated with large increased risk for study withdrawal due to adverse events and dizziness. Sublingual spray with comparable THC-to-CBD ratio (1.1:1) probably is associated with small improvement in pain severity and overall function and may be associated with large increased risk for dizziness and sedation and moderate increased risk for nausea. Evidence for other products and outcomes, including longer-term harms, were not reported or were insufficient. LIMITATION: Variation in interventions; lack of study details, including unclear availability in the United States; and inadequate evidence for some products. CONCLUSION: Oral, synthetic cannabis products with high THC-to-CBD ratios and sublingual, extracted cannabis products with comparable THC-to-CBD ratios may be associated with short-term improvements in chronic pain and increased risk for dizziness and sedation. Studies are needed on long-term outcomes and further evaluation of product formulation effects. PRIMARY FUNDING SOURCE: Agency for Healthcare Research and Quality, U.S. Department of Health and Human Services. (PROSPERO: CRD42021229579).

Statin Use for the Primary Prevention of Cardiovascular Disease in Adults: Updated Evidence Report and Systematic Review for the US Preventive Services Task Force.

Importance: A 2016 review for the US Preventive Services Task Force (USPSTF) found use of statins for primary prevention of cardiovascular disease (CVD) was associated with reduced mortality and cardiovascular outcomes. Objective: To update the 2016 review on statins for primary prevention of CVD to inform the USPSTF. Data Sources: Ovid MEDLINE, Cochrane Central Register of Controlled Trials, and Cochrane Database of Systematic Reviews (to November 2021); surveillance through May 20, 2022. Study Selection: Randomized clinical trials on statins vs placebo or no statin and statin intensity in adults without prior cardiovascular events; large cohort studies on harms. Data Extraction and Synthesis: One investigator abstracted data; a second checked accuracy. Two investigators independently rated study quality. Main Outcomes and Measures: All-cause and cardiovascular mortality, myocardial infarction, stroke, composite cardiovascular outcomes, and adverse events. Results: Twenty-six studies were included: 22 trials (N = 90 624) with 6 months to 6 years of follow-up compared statins vs placebo or no statin, 1 trial (n = 5144) compared statin intensities, and 3 observational studies (n = 417 523) reported harms. Statins were significantly associated with decreased risk of all-cause mortality (risk ratio [RR], 0.92 [95% CI, 0.87 to 0.98]; absolute risk difference [ARD], -0.35% [95% CI, -0.57% to -0.14%]), stroke (RR, 0.78 [95% CI, 0.68 to 0.90]; ARD, -0.39% [95% CI, -0.54% to -0.25%]), myocardial infarction (RR, 0.67 [95% CI, 0.60 to 0.75]; ARD, -0.85% [95% CI, -1.22% to -0.47%]), and composite cardiovascular outcomes (RR, 0.72 [95% CI, 0.64 to 0.81]; ARD, -1.28% [95% CI, -1.61% to -0.95%]); the association with cardiovascular mortality was not statistically significant (RR, 0.91 [95% CI, 0.81 to 1.02]; ARD, -0.13%). Relative benefits were consistent in groups defined by demographic and clinical characteristics, although data for persons older than 75 years were sparse. Statin therapy was not significantly associated with increased risk of serious adverse events (RR, 0.97 [95% CI, 0.93 to 1.01]), myalgias (RR, 0.98 [95% CI, 0.86 to 1.11]), or elevated alanine aminotransferase level (RR, 0.94 [95% CI, 0.78 to 1.13]). Statin therapy was not significantly associated with increased diabetes risk overall (RR, 1.04 [95% CI, 0.92 to 1.19]), although 1 trial found high-intensity statin therapy was significantly associated with increased risk (RR, 1.25 [95% CI, 1.05 to 1.49]). Otherwise, there were no clear differences in outcomes based on statin intensity. Conclusions and Relevance: In adults at increased CVD risk but without prior CVD events, statin therapy for primary prevention of CVD was associated with reduced risk of all-cause mortality and CVD events. Benefits of statin therapy appear to be present across diverse demographic and clinical populations, with consistent relative benefits in groups defined by demographic and clinical characteristics.