Mortality in people who use illicit opioids in England
Authors: Gráinne Cousins, Kathleen E Bennett
Journal: The Lancet Public Health (2021)

People who use illicit opioids have a high risk of premature mortality, with a mortality rate ten times that of the general population.1Larney S Tran LT Leung J et al.All-cause and cause-specific mortality among people using extramedical opioids: a systematic review and meta-analysis.JAMA Psychiatry. 2020; 77: 493-502Crossref PubMed Scopus (34) Google Scholar However, causes of mortality in this group have changed over time in the UK, alongside an ageing and increasingly comorbid population of drug users. The trend in increasing age among people who use illicit opioid has been suggested to be driving the recent increases in drug-related mortality observed in national surveillance data in England.2Public Health EnglandUnderstanding and preventing drug-related deaths: the report of a national expert working group to investigate drug-related deaths in England.https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/669308/Understanding_and_preventing_drug_related_deaths_report.pdfDate: September, 2016Date accessed: November 18, 2021Google Scholar In The Lancet Public Health, Dan Lewer and colleagues3Lewer D Brother TD Van Hest N et al.Causes of death among people who used illicit opioids in England, 2001–18: a matched cohort study.Lancet Public Health. 2021; (published online Dec 11.)https://doi.org/10.1016/S2468-2667(21)00254-1Summary Full Text Full Text PDF PubMed Scopus (3) Google Scholar used a cohort study design to examine the causes of death among people who used illicit opioids in England between 2001–18 compared with a group of individuals matched for age, sex, and general practice with no recorded history of illicit opioid use. They also addressed, as a key policy question, whether population ageing is contributing to increased drug-related mortality. Lewer and colleagues examined data from the Clinical Practice Research Datalink (CPRD) linked to mortality records from the UK Office for National Statistics. In a cohort of 106 789 individuals with a history of illicit opioid use and 320 367 matched controls, the mortality rate among people with a history of illicit opioid use was higher than in the comparison group for all causes of death (13 209 [12·4%] of 106 789 vs 5914 [1·8%] of 320 367), with the most common including drug poisoning (4375 [33·1%] of 13 209), liver disease (1272 [9·6%]), chronic obstructive pulmonary disease (681 [5·2%]), and suicide (645 [4·9%]). In their analyses of age-specific mortality rates, adjusting for calendar year, time after cohort entry, and sex, the rate of drug-poisoning deaths increased gradually, peaking at age 44 years and then decreasing. By contrast, the mortality rate due to cardiovascular disease, respiratory diseases and cancers increased rapidly with age, with the rate of deaths due to non-communicable diseases surpassing the rate of drug-poisoning deaths at age 42 years. In their final analysis, the authors applied age-specific mortality rates from their cohort to the age structure of people who had a history of illicit opioid use in the UK, and observed a 9% increase in the rate of drug-poisoning deaths between 2010 and 2018, compared with an increase of 74% for non-communicable diseases over the same period. This study by Lewer and colleagues3Lewer D Brother TD Van Hest N et al.Causes of death among people who used illicit opioids in England, 2001–18: a matched cohort study.Lancet Public Health. 2021; (published online Dec 11.)https://doi.org/10.1016/S2468-2667(21)00254-1Summary Full Text Full Text PDF PubMed Scopus (3) Google Scholar makes an important contribution to our understanding of the mortality burden associated with illicit opioid use. It is clear from their findings that a one-size-fits-all response to this public health crisis will not protect this vulnerable population over their life course. Increasing access to, and promoting retention in, opioid agonist treatment, along with increased access to naloxone will go a long way to reducing excess mortality from drug poisoning.4Santo Jr, T Clark B Hickman M et al.Association of opioid agonist treatment with all-cause mortality and specific causes of death among people with opioid dependence: a systematic review and meta-analysis.JAMA Psychiatry. 2021; 78: 979-993Crossref PubMed Scopus (56) Google Scholar, 5McDonald R Strang J Are take-home naloxone programmes effective? Systematic review utilizing application of the Bradford Hill criteria.Addiction. 2016; 111: 1177-1187Crossref PubMed Scopus (238) Google Scholar, 6Bird SM McAuley A Scotland's national naloxone programme.Lancet. 2019; 393: 316-318Summary Full Text Full Text PDF PubMed Scopus (13) Google Scholar However, future work is needed to understand what is driving the increase in drug-related deaths, since Lewer and colleagues found that population ageing is an unlikely explanation. They propose, but do not test, alternative explanations for the observed increase in drug-related deaths, including availability and purity of heroin, increased poly-substance use, and reduced investment in community drug treatment and other services. These alternative hypotheses need further exploration. Additionally, increased efforts are needed to address the substantial burden of mortality due to non-communicable diseases among people who use illicit opioids. Lewer and colleagues showed that non-communicable diseases together cause more excess deaths in this population than drug poisonings, and population ageing appears to be driving this effect. Although opioid agonist treatment is associated with reduced mortality due to suicides, cancers, and alcohol-related and cardiovascular-related causes,4Santo Jr, T Clark B Hickman M et al.Association of opioid agonist treatment with all-cause mortality and specific causes of death among people with opioid dependence: a systematic review and meta-analysis.JAMA Psychiatry. 2021; 78: 979-993Crossref PubMed Scopus (56) Google Scholar drug treatment services need to look beyond treating a person's opioid use disorder in isolation from their general medical and health needs, particularly as they age. Lewer and colleagues' findings support conclusions drawn from a recent systematic review of all-cause and cause-specific mortality among people who use illicit opioids;1Larney S Tran LT Leung J et al.All-cause and cause-specific mortality among people using extramedical opioids: a systematic review and meta-analysis.JAMA Psychiatry. 2020; 77: 493-502Crossref PubMed Scopus (34) Google Scholar there is an urgent need to scale-up combination interventions across a wider range of health issues for people who use illicit opioids. With more than 78% of the exposed cohort in Lewer and colleagues' study being current smokers, incorporating smoking cessation programmes into drug treatment services has the potential to reduce excess mortality due to cardiovascular disease, respiratory disease, and cancer. Other interventions in this community that have been successful include the roll-out of direct-acting antiviral treatment of hepatitis C in the UK, which resulted in a reduction in hepatitis C related liver disease deaths.7Public Health EnglandHepatitis C in the UK 2020: working to eliminate hepatitis C as a major public health threat.https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/943154/HCV_in_the_UK_2020.pdfDate: 2020Date accessed: November 18, 2021Google Scholar Finally, because approximately two-thirds of people who use illicit opioids are men, combining data across men and women potentially masks important differences. Although, biological, social, and psychological differences might affect mortality outcomes, sex differences are rarely considered.8Lynn E Doyle A Keane M Bennett K Cousins G Drug poisoning deaths among women: a scoping review.J Stud Alcohol Drugs. 2020; 81: 543-555Crossref PubMed Scopus (3) Google Scholar Lewer and colleagues presented stratified analyses by sex in their appendix, and it is clear, from the sex-specific standardised mortality ratio, that the impact of some non-communicable diseases is more acute among women than men. For example, the rate of deaths due to suicide was 16 times the expected rate among women using illicit opioids compared with women in the general population, whereas for men the rate of deaths due to suicide was five times the expected rate. Drug policies and treatment services need to consider the particular challenges and needs of women who use illicit opioids over their life course.9McHugh RK Votaw VR Sugarman DE Greenfield SF Sex and gender differences in substance use disorders.Clin Psychol Rev. 2018; 66: 12-23Crossref PubMed Scopus (265) Google Scholar, 10Mazure CM Fiellin DA Women and opioids: something different is happening here.Lancet. 2018; 392: 9-11Summary Full Text Full Text PDF PubMed Scopus (54) Google Scholar We declare no competing interests. Causes of death among people who used illicit opioids in England, 2001–18: a matched cohort studyPeople who use illicit opioids have excess risk of death across all major causes of death we analysed. Our findings suggest that population ageing is unlikely to explain the increasing number of fatal drug poisonings seen in surveillance data, but is associated with many more deaths due to non-communicable diseases. Full-Text PDF Open Access