Introduction

Over the course of this book, we have examined many aspects of a particularly complex problem. In this chapter, we summarise the major findings from each of the areas covered and, briefly, look to the future.

Why should society care about drug-related death?

The question posed early in this book was: Does drug-related death matter? While it is undeniable that drug use and drug-related mortality have increased, should this be seen as a significant concern for society? As we saw, arguments could be made that these deaths are self-inflicted, and may even be of benefit to society due to reductions in crime and disease (Chapter 1). If we exclude simple compassion, which not all in a society would share, can the allocation of attention and resources to this problem be justified?

As was seen, the argument that death due to illicit drug use is an essentially self-inflicted harm does not stand up to any close intellectual scrutiny. Drug dependence is not an act of free will made in the absence of precipitating causes. There are a number of well-delineated psychosocial factors that engender dependent illicit drug use, most particularly the clinical picture of a “shattered childhood”. Furthermore, and most importantly, we have seen that the majority of drug-related fatalities occur amongst drug-dependent individuals.

Introduction

The preceding chapters have presented detailed analyses of the major causes of illicit drug-related mortality, as well as the demographic characteristics of drug-related fatalities, possible mechanisms, and risk factors for such deaths. In this chapter we examine various means of reducing such deaths. Some interventions are well established, such as the various treatment modalities for opioid dependence. Others have been proposed, but have yet to be implemented and/or evaluated. The area of drug-related traumatic injury has not been addressed at all by intervention, so any discussion is necessarily speculative.

Drug treatment

As noted in Chapter 3, drug-dependence treatment has a substantial role in reducing mortality and morbidity associated with illicit drug use. This is especially true in the context of opioid dependence, the drug class associated with the greatest risk of death (cf. Chapter 3). The strongest, and largest body, of research in this regard comes from studies of methadone-maintenance treatment (and other opioid replacement therapies), and its effect on drug-injecting behaviour and mortality rates. This is not, of course, to suggest that retention in other forms of long-term treatment, such as drug-free residential rehabilitation, do not reduce risk of death. Indeed, long-term retention in both maintenance and residential rehabilitation have been demonstrated to reduce the risk of non-fatal heroin overdose (Darke et al., 2005f; Stewart et al., 2002), and thus the risk of one of the major killers of opioid users.

Introduction

In this chapter we examine deaths attributable to trauma. Death from trauma among illicit drug users is understudied by comparison with overdose and human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS), but, nonetheless, there are strong reasons for believing that it plays a role in premature mortality. Firstly, there are lifestyle factors surrounding illicit drug use that suggest that trauma may play a significant role in causing illicit drug user deaths. Illicit drugs are expensive, and highly sought after by dependent drug users. The scope for violence in such circumstances is high. High levels of crime and sex work performed to support drug use are well documented (Flynn et al., 2003; Gossop et al., 1998; Kaye et al., 1998), activities that carry a high trauma risk. At the psychological level, there is a strong association between antisocial personality disorder (ASPD), borderline personality disorder (BPD) and dependent drug use, diagnoses specifically associated with impulsivity, risk-taking and violent behaviours (American Psychiatric Association, 2000). In addition to the more direct results of the illicit drug using lifestyle, there is also a strong association between motor vehicle accident (MVA) trauma, other accidents and illicit drug use (Kelly et al., 2004; Turk & Tsokos, 2004). Finally, there are the specific psychotropic effects of particular drugs to consider.

Introduction

This chapter will examine the major diseases associated with illicit drug use, and their contribution to mortality. As noted in Chapter 3, there are specific disease risks that are associated with illicit drug use that increase its salience as a cause of premature death. The impact that disease makes upon illicit drug using populations is illustrated in Table 5.1. In many of the studies of illicit drug user deaths conducted since the 1980s (after the advent of the human immunodeficiency virus (HIV) pandemic) the majority of the cohort have died as a result of disease, mostly commonly acquired immunodeficiency syndrome (AIDS) (Bargagli et al., 2001; Goedert et al., 1995; Langendam et al., 2001; Maxwell et al., 2005; Rehm et al., 2005; Zaccarelli et al., 1994).

In terms of the major diseases, drug injectors are at particular risk of infection with HIV or hepatitis C virus (HCV) through the sharing of injection equipment, and through unprotected sexual activity (in the case of HIV). HIV is a major cause of mortality among injecting drug users (IDU), as can clearly be seen in the studies presented in Table 5.1. Deaths related to chronic HCV infection may also constitute an increasingly important cause of mortality among this group.

Introduction

In this chapter we examine the epidemiology of illicit drug-related death. Specifically, this chapter presents rates of mortality amongst illicit drug users from all causes, the demography of cases, and the associated risk factors. As any discussion of illicit drug-related mortality must necessarily discuss the issues surrounding the estimation of drug-related mortality, they are examined first. Rates of death due to specific causes will be examined in subsequent chapters, as will the specific factors associated with these causes.

Problems in estimating mortality

A number of problems arise when attempting to estimate global mortality attributable to illicit drug use (cf. Degenhardt et al., 2004a). Part of the problem arises from the very fact that the drugs in question are illicit, and that these deaths thus occur amongst “hidden” populations. Whilst a death may be attributable to illicit drug use, the use of these drugs may well have been concealed by the individual. As such, the link to illicit drug use may not be formally recognised as the cause of death, or as a factor associated with the death. A good example is the completed suicide of an illicit drug user, an issue addressed in detail in a later chapter. If the suicide method is by means of an illicit drug overdose, then the death will be clearly attributable to illicit drug use.

Introduction

Over the course of the past 40 years, the use of illicit drugs has increased dramatically in developed nations. Over this period there have been substantial increases in the use of cannabis, opioids, cocaine, amphetamine, and, more recently, amphetamine-like substances such as MDMA (“ecstasy”) (cf. Chapter 2). While the initial increase in illicit drug use occurred within developed nations, recent years have seen large increases in illicit drug use in the developing world. In particular, since the 1990s there have been substantial increases in rates of drug use and drug-related problems in countries such as China, India, and the Republics of the former Soviet Union (Degenhardt et al., 2004a; United Nations Office for Drug Control, 2005).

Clearly, the use of illicit drugs has become an issue worldwide, although the nature of the problem may well vary from nation to nation. In some nations cocaine may be the primary focus, whilst in others opiates may dominate clinical concern. A natural corollary of any increase in the use of illicit substances of any sort, however, is an increase in rates of illicit drug-related death. The use of illicit drugs carries risks for morbidity and mortality, either directly related to the drug itself (e.g. overdose) or as a consequence of such use (e.g. intoxicated driving).

Introduction

The current chapter examines mortality attributable to drug overdose, the dynamics of which are still poorly understood. The two main drug classes implicated, and the ones upon which the most work has been conducted, are opioids and cocaine. Fatal overdoses from amphetamine toxicity, and from methylenedioxymethamphetamine (MDMA) and other so-called “party drugs”, are less well documented. In any discussion of overdose mortality, it is also clearly important to examine the related issue of non-fatal overdose. Non-fatal overdose is a far more common occurrence than fatal overdose, and is associated with a range of serious sequelae.

Rates of overdose

Opioid overdose is a major cause of premature death among heroin users (European Monitoring Centre for Drugs and Drug Addiction, 2004; US Department of Health and Human Services, 2005), and there have been strong trends internationally for the rates of such deaths to have increased dramatically in recent decades (Coffin et al., 2003; Drucker, 1999; Hall et al., 2000; Hickman et al., 2003; Preti et al., 2002; Steentoft et al., 1996). By way of example, between 1985–1995 the percentage of all deaths in Britain attributed to opioid overdose increased from 0.02% to 0.12%, and in Australia from 0.2 to 0.5% (Hall et al., 2000).

Introduction

Despite its salience as a cause of death amongst illicit drug users, suicide has been a relatively neglected area of research in the drug and alcohol field. This is curious because, as noted previously, it has long been known that there are extremely high levels of depressive disorders amongst this population (Darke & Ross, 2001; Degenhardt et al., 2001; Dinwiddie et al., 1997; Teesson et al., 2005), and suicide is a leading cause of death amongst illicit drug users. Despite its status as a “hidden issue” of the illicit drug field, however, suicide presents a major clinical challenge to those treating drug-dependent users, and needs to be recognised as such. The current chapter examines rates of suicide, methods employed, and risk factors amongst the general population and illicit drug users. Both completed and attempted suicide are examined, representing two aspects of a single phenomenon.

Suicide amongst the general population

Rates of completed suicide in the general population vary greatly from country to country. For example, rates higher than 0.3 per thousand are reported in Finland, Hungary, and Sri Lanka compared to rates of approximately 0.1 per thousand in the US, UK, and Australia (Diekstra & Gulbinat, 1993; Hassan, 1995; Lynskey et al., 2000).