Cited by 307Opioid Use Disorder TreatmentSubstance Abuse Treatment and OutcomesHIV, Drug Use, Sexual Risk

The DOI matches its Crossref record; 45 of the 46 references it cites were found in a registry or an index; none of the 38 sources its claims cite is checked for support yet.

Risk of death during and after opiate substitution treatment in primary care: prospective observational study in UK General Practice Research Database

Open access

Abstract

OBJECTIVE: To investigate the effect of opiate substitution treatment at the beginning and end of treatment and according to duration of treatment. DESIGN: Prospective cohort study. Setting UK General Practice Research Database. PARTICIPANTS: Primary care patients with a diagnosis of substance misuse prescribed methadone or buprenorphine during 1990-2005. 5577 patients with 267 003 prescriptions for opiate substitution treatment followed-up (17 732 years) until one year after the expiry of their last prescription, the date of death before this time had elapsed, or the date of transfer away from the practice. MAIN OUTCOME MEASURES: Mortality rates and rate ratios comparing periods in and out of treatment adjusted for sex, age, calendar year, and comorbidity; standardised mortality ratios comparing opiate users' mortality with general population mortality rates. RESULTS: Crude mortality rates were 0.7 per 100 person years on opiate substitution treatment and 1.3 per 100 person years off treatment; standardised mortality ratios were 5.3 (95% confidence interval 4.0 to 6.8) on treatment and 10.9 (9.0 to 13.1) off treatment. Men using opiates had approximately twice the risk of death of women (morality rate ratio 2.0, 1.4 to 2.9). In the first two weeks of opiate substitution treatment the crude mortality rate was 1.7 per 100 person years: 3.1 (1.5 to 6.6) times higher (after adjustment for sex, age group, calendar period, and comorbidity) than the rate during the rest of time on treatment. The crude mortality rate was 4.8 per 100 person years in weeks 1-2 after treatment stopped, 4.3 in weeks 3-4, and 0.95 during the rest of time off treatment: 9 (5.4 to 14.9), 8 (4.7 to 13.7), and 1.9 (1.3 to 2.8) times higher than the baseline risk of mortality during treatment. Opiate substitution treatment has a greater than 85% chance of reducing overall mortality among opiate users if the average duration approaches or exceeds 12 months. CONCLUSIONS: Clinicians and patients should be aware of the increased mortality risk at the start of opiate substitution treatment and immediately after stopping treatment. Further research is needed to investigate the effect of average duration of opiate substitution treatment on drug related mortality.

Overview

AI snapshot

Written from the paper’s full text.

TL;DR

In a UK primary care cohort of opiate users prescribed methadone or buprenorphine, mortality was lower during opiate substitution treatment than off treatment, but risk was elevated in the first weeks of treatment and immediately after stopping. The authors estimate that treatment is likely to reduce overall mortality only when average duration approaches or exceeds 12 months.

Key findings

  • Crude mortality was 0.7 per 100 person years on treatment versus 1.3 per 100 person years off treatment; adjusted mortality rate ratio off versus on treatment was 2.29 (95% CI 1.67 to 3.14), and standardised mortality ratios were 5.3 (4.0 to 6.8) on treatment and 10.9 (9.0 to 13.1) off treatment.
  • In the first two weeks of treatment, crude mortality was 1.7 per 100 person years, with an adjusted rate ratio of 3.11 (1.47 to 6.59) compared with the remainder of time on treatment; weeks 3-4 had a crude rate of 1.32 per 100 person years and adjusted rate ratio 2.38 (0.95 to 5.99).
  • After treatment stopped, crude mortality was 4.80 per 100 person years in weeks 1-2 and 4.25 in weeks 3-4, with adjusted rate ratios of 9.01 (5.43 to 14.90) and 8.01 (4.70 to 13.66) versus the stable on-treatment period; during the remainder of time off treatment, the crude rate was 0.95 per 100 person years and adjusted rate ratio 1.91 (1.32 to 2.76).
  • The modelled probability that opiate substitution treatment reduces overall mortality was less than 25% at 20-30 weeks’ average duration, 65% at 40 weeks, and greater than 85% if average duration approaches or exceeds 12 months.

Methods

  • Prospective cohort study using the UK General Practice Research Database, including primary care patients with a diagnosis of substance misuse prescribed methadone or buprenorphine during 1990-2005: 5,577 patients, 267,003 prescriptions, and 17,732 person years of follow-up until one year after the last prescription, death, or transfer away from the practice.
  • Time on treatment was defined from prescription expiry, with gaps of less than 28 days counted as on treatment; oral dihydrocodeine prescriptions were included as opiate substitution treatment.
  • Poisson regression estimated mortality rate ratios adjusted for sex, age group, calendar period, comorbidity score, treatment episode, and episodes with at least one dose at or above recommended maintenance thresholds; indirect standardised mortality ratios used 1998 sex-specific death rates for England and Wales, with sensitivity analyses restricted to final treatment episodes and excluding dihydrocodeine.

Limitations

  • The paper states that classification of time on and off treatment was complicated by gaps in dose, duration, or quantity data, which may have diluted or exaggerated mortality differences; findings were similar in a sensitivity analysis restricted to the last treatment episode.
  • The paper states that patients transferring out of the database had no active follow-up, that their characteristics differed from those completing follow-up, and that unrecorded confounders could bias results; follow-up was restricted to 12 months after treatment to limit misclassification.
  • The paper states that covariates were limited, the comorbidity index was not ideal or opiate-specific, there was no measure of intervention quality or intensity, outcome was all-cause mortality without cause-specific data, and the duration analyses were modelled rather than directly observed; evident from the text, the observational design cannot establish causality.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.1136/bmj.c5475

Cites

45 of 45 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Figures

Fig 1 Adjusted risk of death, compared with not being on treatment, during and after opiate substitution treatment
Fig 1 Adjusted risk of death, compared with not being on treatment, during and after opiate substitution treatmentCC BY-NC · PubMed Central
Fig 2 Comparison of risk of death in patients exposed or not exposed to opiate substitution treatment (OST) by duration of treatment. Boxes are interquartile ranges (with median); lines are 95% confidence intervals
Fig 2 Comparison of risk of death in patients exposed or not exposed to opiate substitution treatment (OST) by duration of treatment. Boxes are interquartile ranges (with median); lines are 95% confidence intervalsCC BY-NC · PubMed Central
Fig 3 Probability that opiate substitution treatment (OST) reduces overall mortality for different durations of treatment
Fig 3 Probability that opiate substitution treatment (OST) reduces overall mortality for different durations of treatmentCC BY-NC · PubMed Central

Verification

Claims the paper makes

34 Own result · 24 Not checked yet · 19 Own method · 8 Own interpretation · 1 No basis given

Verify all 38 references — free account

Show all 48 claims

  • It may state two separate claims as one. 19
  • Probably not a substantial claim. 23
38 of 38
  • The paper relies on this without support.

    The General Practice Research Database accurately and completely records prescriptions, diagnoses, and deaths for the study population.

    “The data for this study come from the General Practice Research Database (www.gprd.com), a large database of anonymised patients’ records from more than 460 general practices in the UK. It collects data from 3.5 million patients, equivalent to around 5.5% of the UK’s population.”
  • The paper relies on this without support.

    Patients in the General Practice Research Database with a diagnosis of substance misuse prescribed methadone or buprenorphine are representative of opiate users receiving opiate substitution treatment in UK primary care.

    “The study cohort consisted of patients who received at least one prescription for methadone or buprenorphine between 1 January 1990 and 31 December 2005 and who had a recorded diagnosis of substance misuse.”
  • The paper relies on this without support.

    Patients do not genuinely stop and restart opiate substitution treatment within a four-week period in general practice.

    “We chose this period because the prescription data within long term treatment episodes could be incomplete and we considered it unlikely that a patient would genuinely stop and restart treatment in general practice within a four week period.”
  • The paper relies on this without support.

    The model used to project the effect of average duration of opiate substitution treatment on mortality is correctly specified.

    “Opiate substitution treatment has a greater than 85% chance of reducing overall mortality among opiate users if the average duration approaches or exceeds 12 months.”
  • The paper relies on this without support.

    The adjusted mortality rate ratios are not substantially confounded by unmeasured factors.

    “We used Poisson regression to estimate mortality rate ratios comparing periods in and out of treatment, adjusted for potential confounders (sex, age group, calendar period, comorbidity score, treatment episode, and episodes with one opiate substitution treatment at or above recommended levels for maintenance).”
  • The authors state this as an assumption.

    The mortality of patients who transferred out of the database was the same as for those who remained in their practice, given adjustment for the characteristics that were recorded.

    “We assumed, therefore, that the mortality of patients who transferred was the same as for those who remained in their practice, given adjustment for the characteristics that were recorded.”
  • The paper relies on this without support.

    The General Practice Research Database provides a large, reasonably representative sample of patients taking opiate substitution treatment.

    “The General Practice Research Database covers approximately 5% of the population in general practice and provides a large, reasonably representative sample of patients taking opiate substitution treatment.”
  • The paper relies on this without support.

    Some patients who left treatment will have stopped their opiate use and therefore have been at substantially less risk of death than patients who relapsed.

    “In addition, some patients who left treatment will have stopped their opiate use (and therefore have been at substantially less risk of death than were patients who relapsed).”
8 of 8

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

3 of 3

Citations

Cites

Show all 46 references

Cited by

Sorted by citations

See all 307

Metadata

Authors
Cornish, R., Macleod, J., Strang, J., Vickerman, P., & Hickman, M.
Affiliations
  • University of Bristol (GB)
  • King's College London (GB)
Corresponding author
Hickman, M.
Venue
BMJ
Publisher
BMJ
Published
2010-10-26
Volume
341
Issue
oct26 2
Pages
c5475-c5475
ISSN
  • 0007-1447 (ISSN-L)
  • 0959-8138
  • 1468-5833
OpenAlex
W1965862609
Cited by
307
References
46
Citations by year
2026: 2 · 2025: 13 · 2024: 11 · 2023: 11 · 2022: 11 · 2021: 30 · 2020: 27 · 2019: 21 · 2018: 24 · 2017: 23 · 2016: 19 · 2015: 28 · 2014: 23 · 2013: 20 · 2012: 21
FWCI
19.97
Type
journal article
Language
en
Open access
Licence
cc-by-nc
Locations
  • BMJ (publishedVersion, cc-by-nc)
  • PubMed Central (publishedVersion, cc-by-nc)
  • PubMed (publishedVersion)
  • LSHTM Research Online (London School of Hygiene and Tropical Medicine) (acceptedVersion)
  • Research Portal (King's College London) (submittedVersion)
  • Explore Bristol Research (submittedVersion)
Funders
Economic and Social Research Council (ES/G007543/1)
Topics
  • Health Sciences › Medicine › Public Health, Environmental and Occupational Health › Opioid Use Disorder Treatment
  • Health Sciences › Medicine › Epidemiology › Substance Abuse Treatment and Outcomes
  • Health Sciences › Medicine › Epidemiology › HIV, Drug Use, Sexual Risk
Keywords
opioid substitution therapy, mortality, methadone, buprenorphine, opioid use disorder, substance abuse, treatment duration, early mortality risk, sex differences in mortality, primary care, general practice
MeSH terms
Adolescent, Adult, Buprenorphine, Female, United Kingdom, Humans, Male, Methadone, Middle Aged, Opioid-Related Disorders, Narcotics, Prospective Studies, Risk Factors, Time Factors, Young Adult

About these checks

Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

A language model drew the claims from the paper on 2026-10-06, under version 3 of the claim definition (model deepseek-v4.1-flash, prompt extract-v3).

A second model labelled each claim on 2026-10-06 (model jev-1.13-20260917, definition revision gold-guideline-v0.2).

Statistics and arithmetic are recomputed, not judged.

Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.

What counts as a claim ›How we measure confidence ›How we check this ›

Are you an author, or do you see a problem with this page? Request a review