Death rates in Scotland are higher than in England and Wales, and a new study published on bmj.com finds that drug abuse in Scotland is a key factor contributing to this difference. In fact, researchers report that about a third of Scotland’s higher death rate can be explained by drug abuse.
In the past, higher levels of deprivation in Scotland have been cited as the cause of the relatively higher – and increasingly higher – death rates in Scotland compared to England and Wales. However, higher levels of deprivation only really explain less than half of the difference in death rates between Scotland and England, leaving more than 50% unaccounted. Researchers have termed this strange “excess” of deaths in Scotland the “Scottish effect.”
Professor Michael Bloor (University of Glasgow) and colleagues set out to determine whether drug abuse could explain part of the difference in these unaccounted-for deaths. They first analyzed published data on drug-related deaths in Scotland, but found that the data have a particular weakness. They only count death as drug-related if it results from a pharmacological effect of taking the drug, such as an overdose. Therefore, deaths due to drug-related blood-borne infections, suicide, and violent assaults are not included, perhaps masking a much larger problem of drug-related deaths.
The researchers relied on an estimate of the number of deaths in a drug-user population by matching mortality data from Scotland’s General Register Office with participants in the Drug Outcomes Research in Scotland (DORIS) study. In the DORIS study, researchers interviewed (in 2001 and 2002) 1033 problem drug users who started new treatment in any of 33 Scottish drug treatment centers. Some of the patients had follow-up interviews between 2004 and 2005.
Thirty-eight of the patients who failed to have follow-up interviews had died, and 22 of these had been marked as drug-related. Other deaths were due to suicide (6 cases, including three from overdoses of drugs such as paracetamol), an “infection associated with drug abuse” (3 cases), assault (2 cases), “alcoholic liver disease” (1 case), and exposure (1 case).
Other studies have demonstrated that 1.84% of the Scottish population battled drug abuse, while only 0.99% of the English population does. Bloor and colleagues integrated the death rates for drug users in the DORIS study with the general problem of drug abuse in Scotland to estimate that 32% of the excess mortality rate in Scotland can be explained by the country’s greater prevalence of drug abuse.
“Problem drug use is a low prevalence risk behaviour compared with tobacco consumption, high alcohol consumption, and low levels of physical activity, but it carries a high mortality: mortality in the DORIS sample was 12 times that of the general Scottish population aged 15 to 54Compared to smoking, excess drinking, or lack of exercise, relatively few people have a problem with drug abuse.” write the authors. They conclude that, “Successful public health initiatives to reduce the prevalence of problem drug use or to reduce deaths among drug users would have a strong impact on overall mortality in both Scotland and England.”
Contribution of problem drug users’ deaths to excess mortality in Scotland: secondary analysis of cohort study
Michael Bloor, Maria Gannon, Gordon Hay, Graham Jackson, Alastair H Leyland, Neil McKeganey
BMJ (2008). 337: a478.
Written by: Peter M Crosta