Sleep Quality Improved Early and Stayed Better Over 12 Months of Medical Cannabis Use
Adults initiating medical cannabis in Pennsylvania reported significant improvements in sleep quality within 3 months that were sustained through 12 months.
Quick Facts
What This Study Found
Global sleep quality scores (PSQI) were significantly higher at baseline than at each follow-up point (p < 0.0001), with no significant differences among the 3-, 6-, 9-, and 12-month follow-ups, indicating early and sustained improvement. Benefits were seen across all PSQI subscales regardless of administration route or referring condition.
Key Numbers
137 participants followed for 12 months. Significant improvement in PSQI global scores at each follow-up vs. baseline (p < 0.0001). Improvements observed across all PSQI subscales. No differences by administration route (oral vs. other) or referring condition (chronic pain, anxiety, PTSD).
How They Did This
Prospective observational study of 137 adults newly referred for medical cannabis in Pennsylvania. Participants completed the Pittsburgh Sleep Quality Index at baseline and at 3, 6, 9, and 12 months. Linear mixed effects models assessed changes over time and whether route of administration or referring condition modified outcomes.
Why This Research Matters
Poor sleep is one of the most common reasons people seek medical cannabis, but most evidence comes from short-term studies. This 12-month follow-up provides longer-term data on whether sleep improvements persist.
The Bigger Picture
These findings add to growing evidence that medical cannabis may help with sleep, but the lack of a control group means improvements could reflect placebo effects, natural symptom fluctuation, or concurrent treatments.
What This Study Doesn't Tell Us
No control group or blinding. Self-reported sleep quality only, no objective sleep measures. Relatively small sample size (137). Potential selection bias from participants willing to complete multiple follow-ups. Products and doses were not standardized.
Questions This Raises
- ?Would objective sleep measures like actigraphy confirm these self-reported improvements?
- ?Do sleep benefits persist beyond 12 months?
Trust & Context
- Key Stat:
- Evidence Grade:
- Prospective design with repeated measures and validated instrument strengthens findings, but lack of control group and reliance on self-report limit the evidence to moderate.
- Study Age:
- Recent prospective study from Pennsylvania's medical cannabis program.
- Original Title:
- Changes in sleep quality during the 12 months following medical cannabis initiation.
- Published In:
- Journal of cannabis research, 7(1), 106 (2025)
- Authors:
- Short, Megan M, Lent, Michelle R(3), McCalmont, Thomas R, Dugosh, Karen L
- Database ID:
- RTHC-07646
Evidence Hierarchy
Watches what happens naturally without intervening.
What do these levels mean? →Frequently Asked Questions
Did the type of cannabis product matter?
No. The study found no significant differences in sleep improvement between oral and other administration routes.
Did the reason for using medical cannabis affect sleep outcomes?
No. Improvements were similar whether the referring condition was chronic pain, anxiety, or PTSD.
Read More on RethinkTHC
Cite This Study
https://rethinkthc.com/research/RTHC-07646APA
Short, Megan M; Lent, Michelle R; McCalmont, Thomas R; Dugosh, Karen L. (2025). Changes in sleep quality during the 12 months following medical cannabis initiation.. Journal of cannabis research, 7(1), 106. https://doi.org/10.1186/s42238-025-00376-7
MLA
Short, Megan M, et al. "Changes in sleep quality during the 12 months following medical cannabis initiation.." Journal of cannabis research, 2025. https://doi.org/10.1186/s42238-025-00376-7
RethinkTHC
RethinkTHC Research Database. "Changes in sleep quality during the 12 months following medi..." RTHC-07646. Retrieved from https://rethinkthc.com/research/short-2025-changes-in-sleep-quality
Access the Original Study
Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.
This study breakdown was produced by the RethinkTHC research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.