Commentary on Chang <i>et al</i> .: Drugs, disease and death

The mechanisms of opioid and psychostimulant ‘overdoses’ are distinct, as are their chronic effects. Understanding these differences is crucial to inform interventions to improve the quality of life for people who use these drugs, and to reduce their risk of death from drug toxicity. The work by Chang and colleagues [1] is an important contribution to our understanding of drug-related death. Why does understanding death matter? The dead have much to teach the living. If we can understand why, and how, people die from various forms of drug toxicity, we will be better informed to prevent such deaths. In this work, the authors draw our attention to the important differences between opioid and psychostimulant toxicity deaths, and the role of cardiovascular and cerebrovascular disease in the latter. There are two important points here. First, that the mechanisms of opioid and psychostimulant ‘overdoses’ are distinct. Opioids lead to depressed respiration resulting from central nervous system (CNS) depression. Heart failure may occur secondary to respiratory failure, but it is respiration that is the primary mechanism. In contrast, psychostimulant toxicity relates primarily to the cardiovascular system, leading to psychostimulant-induced arrhythmia, coronary infarction and stroke. Indeed, the term overdose may not be appropriate for psychostimulant-related deaths. The second important point raised in this article that distinguishes opioids from psychostimulants is the chronic effect of psychostimulants on the cardiovascular system. Chronic pathologies caused by psychostimulant use include cardiomegaly, ventricular hypertrophy, accelerated atherosclerotic coronary artery disease, ischaemic heart disease, hypertensive heart disease and cardiomyopathy. Indeed, it has been observed that we frequently see 70-year-old hearts in 30-year-old bodies. The use of a psychostimulant in the presence of such pathology increases the risk of acute cardiovascular effects, such as a fatal arrhythmia. In contrast, opioids have no such effects upon the cardiovascular system. Consistent with what we know about psychostimulants, Chang and colleagues found that psychostimulant-only deaths were significantly more likely than those involving opioids to have cardiovascular and cerebrovascular disease noted in the cause of death. These deaths were more likely to be a complex interaction of acute drug effects and chronic disease than an overdose per se. A great deal of attention has been devoted over the years to psychiatric co-morbidity. The work of Chang and colleagues reminds us of the clinical importance of physical comorbidity. My colleagues and I recently drew attention to the underappreciated role of chronic obstructive pulmonary disease in heroin overdose deaths [2]. Chang and colleagues draw our attention to the importance of cardiovascular disease in psychostimulant deaths. The clinical monitoring and treatment of such comorbidities may not only improve the quality of life for people who use these drugs, but reduce their risk of death from drug toxicity. Shane Darke: Conceptualization; writing—original draft. None. None.