Trial reportPain2011
Prescription opioid analgesics rapidly change the human brain.
Trial report in Pain, 2011. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 90 papers, 2 of them syntheses that pooled it.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
90 citing papers in PubMed, 2 syntheses or guidelines pooled it, 203 citations in OpenAlex.
- Cognitive and Motor Outcomes of Children With Prenatal Opioid Exposure: A Systematic Review and Meta-analysis.JAMA network open · 2019Pooled it
- Gray matter alterations in chronic pain: A network-oriented meta-analytic approach.NeuroImage. Clinical · 2014Pooled it
- One Month of Oral Morphine Decreases Gray Matter Volume in the Right Amygdala of Individuals with Low Back Pain: Confirmation of Previously Reported Magnetic Resonance Imaging Results.Pain medicine (Malden, Mass.) · 2016Trial
- Effects of morphine self-administration on brain structure and microglial phenotypic diversity in the absence of neuronal loss in male Wistar rats.Psychopharmacology · 2026Article
- Distinct Grey Matter Alterations in Untreated Mild to Moderate Chronic Low Back Pain: A Longitudinal Magnetic Resonance Imaging Study.European journal of pain (London, England) · 2026Observational
- Positive Emotion Regulation in Addiction: A New Frontier for Recovery Science.Current addiction reports · 2026Review
- Association of brain cortical changes with efficacy of treatment in patients with chronic neck and shoulder pain: a longitudinal surface-based morphometry study.Frontiers in neuroscience · 2026Article
- Prevalence and Associated Factors of Central Sensitization Among Patients with Chronic Low Back Pain at Mbarara Regional Referral Hospital, Uganda: A Cross-Sectional Study.Journal of pain research · 2026Article
- Animal Models of Prenatal Opioid Exposure: Insights into Impaired Neurodevelopment.Advances in experimental medicine and biology · 2026Review
- Beyond pain relief: the effects of chronic opioid use on brain structure and function in diabetic neuropathy-a multimodal neuroimaging study.Diabetologia · 2025Article
- Cross-sectional relationships between spinal cord gray matter volume and pain in individuals with fibromyalgia and opioid use.Scientific reports · 2025Article
- Osteoarthritis, osteoarthritis treatment and risk of incident dementia: a prospective cohort study based on UK Biobank.Age and ageing · 2024Article
- Neuroimaging of opioid effects in humans across conditions of acute administration, chronic pain therapy, and opioid use disorder.Trends in neurosciences · 2024Review
- Prescription Opioids and Brain Structure in Community-Dwelling Older Adults.Mayo Clinic proceedings · 2024Article
- Baseline Characteristics From a New Longitudinal Cohort of Patients With Noncancer Pain and Chronic Opioid Use in the United States.The journal of pain · 2024Article
- Macroscopic and Microscopic Cerebral Findings in Drug and Alcohol Abusers: The Point of View of the Forensic Pathologist.Biomedicines · 2024Review
- Pain, Opioid Analgesics, and Cognition: A Conceptual Framework in Older Adults.Pain medicine (Malden, Mass.) · 2023Article
- A scoping review of outpatient interventions to support the reduction of prescription opioid medication for chronic non cancer pain.Journal of clinical nursing · 2022Article
- Is there hemispheric specialization in the chronic pain brain?Experimental neurology · 2022Review
- Altered resting-state functional connectivity within corticostriatal and subcortical-striatal circuits in chronic pain.Scientific reports · 2022Article
30 more citing papers are in PubMed but not listed here.
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
6 authors at 2 institutions in 1 country.
Funding
Abstract
Chronic opioid exposure is known to produce neuroplastic changes in animals; however, it is not known if opioids used over short periods of time and at analgesic dosages can similarly change brain structure in humans. In this longitudinal, magnetic resonance imaging study, 10 individuals with chronic low back pain were administered oral morphine daily for 1 month. High-resolution anatomical images of the brain were acquired immediately before and after the morphine administration period. Regional changes in gray matter volume were assessed on the whole brain using tensor-based morphometry, and those significant regional changes were then independently tested for correlation with morphine dosage. Thirteen regions evidenced significant volumetric change, and degree of change in several of the regions was correlated with morphine dosage. Dosage-correlated volumetric decrease was observed primarily in the right amygdala. Dosage-correlated volumetric increase was seen in the right hypothalamus, left inferior frontal gyrus, right ventral posterior cingulate, and right caudal pons. Follow-up scans that were conducted an average of 4.7 months after cessation of opioids demonstrated many of the morphine-induced changes to be persistent. In a separate study, 9 individuals consuming blinded placebo capsules for 6 weeks evidenced no significant morphologic changes over time. The results add to a growing body of literature showing that opioid exposure causes structural and functional changes in reward- and affect-processing circuitry. Morphologic changes occur rapidly in humans during new exposure to prescription opioid analgesics. Further research is needed to determine the clinical impact of those opioid-induced gray matter changes.
Indexed as
Identifiers
What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.