Jurisdictional trends in opioid overdose deaths, 1988-96

Risk markers for fatal and non-fatal prescription drug overdose: a meta-analysis

BACKGROUND

Drug overdose is a public health crisis in the United States, due in part to the unintended consequences of increases in prescribing of opioid analgesics. Many clinicians evaluate risk markers for opioid-related harms when prescribing opioids for chronic pain; however, more data on predictive risk markers are needed. Risk markers are attributes (modifiable and non-modifiable) that are associated with increased probability of an outcome. This review aims to identify risk markers associated with fatal and non-fatal prescription drug overdose by synthesizing findings in the existing peer-reviewed and grey literature. Eligible cohort, case-control, cross-sectional, and case-cohort studies were reviewed and data were extracted for qualitative and quantitative synthesis.

FINDINGS

Summary odds ratios (SOR) were estimated from 29 studies for six risk markers: sex, age, race, psychiatric disorders, substance use disorder (SUD), and urban/rural residence. Heterogeneity was assessed and effect estimates were stratified by study characteristics. Of the six risk markers identified, SUD had the strongest association with drug overdose death (SOR = 5.24, 95% confidence interval (CI) = 3.53 - 7.76), followed by psychiatric disorders (SOR = 3.94, 95% CI = 3.09 - 5.01), white race (SOR = 2.28, 95% CI = 1.93 - 2.70), the 35-44 year age group relative to the 25-34 year reference group (SOR = 1.52, 95% CI = 1.31 - 1.76), and male sex (SOR = 1.33, 95% CI = 1.17 - 1.51).

CONCLUSIONS

This review highlights fatal and non-fatal prescription drug risk markers most frequently assessed in peer-reviewed and grey literature. There is a need to better understand modifiable risk markers and underlying reasons for drug misuse in order to inform interventions that may prevent future drug overdoses.

Effects of a sustained heroin shortage in three Australian States

BACKGROUND

In early 2001 in Australia there was a sudden and dramatic decrease in heroin availability that occurred throughout the country that was evidenced by marked increases in heroin price and decreases in its purity.

AIM

This study examines the impact of this change in heroin supply on the following indicators of heroin use: fatal and non-fatal drug overdoses; treatment seeking for heroin dependence; injecting drug use; drug-specific offences; and general property offences. The study was conducted using data from three Australian States [New South Wales (NSW), Victoria (VIC) and South Australia (SA)].

METHODS

Data were obtained on fatal and non-fatal overdoses from hospital emergency departments (EDs), ambulance services and coronial systems; treatment entries for heroin dependence compiled by State health departments; numbers of needles and syringes distributed to drug users; and data on arrests for heroin-related incidents and property-related crime incidents compiled by State Police Services. Time-series analyses were conducted where possible to examine changes before and after the onset of the heroin shortage. These were supplemented with information drawn from studies involving interviews with injecting drug users.

RESULTS

After the reduction in heroin supply, fatal and non-fatal heroin overdoses decreased by between 40% and 85%. Despite some evidence of increased cocaine, methamphetamine and benzodiazepine use and reports of increases in harms related to their use, there were no increases recorded in the number of either non-fatal overdoses or deaths related to these drugs. There was a sustained decline in injecting drug use in NSW and VIC, as indicated by a substantial drop in the number of needles and syringes distributed (to 1999 levels in Victoria). There was a short-lived increase in property crime in NSW followed by a sustained reduction in such offences. SA and VIC did not show any marked change in the categories of property crime examined in the study.

CONCLUSIONS

Substantial reductions in heroin availability have not occurred often, but in this Australian case a reduction had an aggregate positive impact in that it was associated with: reduced fatal and non-fatal heroin overdoses; reduced the apparent extent of injecting drug use in VIC and NSW; and may have contributed to reduced crime in NSW. All these changes provide substantial benefits to the community and some to heroin users. Documented shifts to other forms of drug use did not appear sufficient to produce increases in deaths, non-fatal overdoses or treatment seeking related to those drugs.

Deaths by unintentional illicit drug overdose in Italy, 1984-2000

AIM

To determine whether there has been an increase in deaths by overdose in Italy, as elsewhere in the Western world, over the past fifteen years.

METHOD

This study's conclusions are based on analysis of official data on overdose deaths attributed to illicit drug addiction and abuse (ICD-9 codes 304 and 305) from 1984 to 2000, drawn from two archives of drug abuse information: the Direzione Centrale per i Servizi Antidroga (DADE) of the Italian Ministry of the Interior (1984-2000), and the Health Statistics held at the Italian Central Statistics Institute (ISTAT) (1984-1997). Mortality rates have been calculated for both genders in the following age groups: 15-24, 25-34, and 35-44 years.

RESULTS

Official data indicate that there has been a steady increase in the number of deaths by overdose in Italy over recent 15 years. This trend has affected both genders, but is more evident among males. Over the whole period females had consistently lower overdose rates than males. In both genders the age group 35-44 was subject to the highest mortality rate increase over the study period, however, the highest overdose rates for both males and females were observed in the 25-34 age group. Consistently higher rates were witnessed in the northern regions of Italy with an overall increase across all latitudes. However, the greatest increase over the study period occurred in the South. In 5190 cases evaluated by the Italian Forensic Toxicology Group, 95.9% of deaths were attributed to heroin, but in about half of these, mixtures of three or more substances (heroin, benzodiazepines, cannabinoids, cocaine, methadone) were found in the deceased at doses that were likely to have contributed to death.

CONCLUSIONS

The increase observed in the rates of death by overdose is likely to be a reflection of increased use of illicit drugs in the general population. Reporting practice by forensic pathologists might explain the extent of attribution of cause of death to heroin. Drop-out from addiction treatment is a commonly observed antecedent of fatal opioid overdose, therefore, caution is required when establishing treatment protocol for patients. Interventions that aim specifically at improving patient compliance with medical and psychiatric therapies should be favoured.

Opioid overdose mortality in Australia, 1964-1997: birth-cohort trends

OBJECTIVE

To examine trends in rates of opioid overdose deaths from 1964 to 1997 in different birth cohorts.

DESIGN

Age-period-cohort analysis of national data from the Australian Bureau of Statistics.

MAIN OUTCOME MEASURES

Annual population rates of death attributed to opioid dependence or accidental opioid poisoning in people aged 15-44 years, by sex and birth cohort (in five-year intervals, 1940-1944 to 1975-1979).

RESULTS

The rate of opioid overdose deaths increased 55-fold between 1964 and 1997, from 1.3 to 71.5 per million population aged 15-44 years. The rate of opioid overdose deaths also increased substantially over the eight birth cohorts, with an incidence rate ratio of 20.70 (95% confidence interval, 13.60-31.46) in the 1975-1979 cohort compared with the 1940-1944 cohort. The age at which the cumulative rate of opioid overdose deaths reached 300 per million fell in successive cohorts (for men, from 28 years among those born 1955-1959 to 22 years among those born 1965-1974; for women, from 33 years among those born 1955-1959 to 27 years among those born 1965-1969).

CONCLUSIONS

Heroin use in Australia largely began in the early 1970s and rates of heroin use have markedly increased in birth cohorts born since 1950.