For the first time in Spain, a large population-based multicenter study confirmed the prolongation of hospital stay and has quantified the related costs in patients admitted for acute myocardial infarction associated with cocaine use. Moreover, the report provides complementary data on annual hospital admissions attributable to cocaine (0.44%) and on the incidence of acute myocardial infarctions due to its consumption (2.2%).1 However, we would like to comment on certain aspects that we believe could complement the epidemiological data provided in that report.
As the authors indicate in their article, there may be a risk of underreporting and underestimation of the prevalence, as we do not know whether the diagnosis of cocaine use was corroborated by an analytical study or was based solely on the patient's medical history. In the series described by Rodríguez-Esteban et al2 involving hospitalized patients with acute coronary syndrome, the prevalence of cocaine use was somewhat higher (3.7%), although that study showed the same methodological bias. These authors carried out a greater number of coronary angiographies (94% vs 82.4%; P<.01), but most of the patients had no significant coronary lesions or had single-vessel disease. Unfortunately, the authors did not evaluate the length or costs of the hospital stays.
The 1996-2009 Report on Emergency Hospital Care for users of psychoactive substances issued by the Spanish National Plan on Drugs,3 based on data from 2009, included patients with diagnoses coded according to the 10th revision of the International Classification of Diseases (ICD-10) and whose medical history made reference to cocaine consumption. In this report, the latter was the most commonly used drug (61.3%), and the incidence of hospital admission ranged between 7.2% and 9.8%, depending on whether there was a direct or a secondary relationship between cocaine use and the need for hospital care. In a review carried out by our group based on data on emergency care in cocaine users,4 cardiovascular symptoms were detected in 30% (standard deviation, 22.7%).
As the authors point out, there may also be cases of undisclosed cocaine use which, according to our findings in emergency departments, ranges between 6.4% and 21%, depending on the populations studied and the diagnosis or the reported reason for consultation.5–7 Likewise, some patients may have taken a substance other than cocaine.8 However, in this case, it would have no bearing on the phenomenon of cardiovascular risk associated with chronic use or on prevention strategies. As the authors indicate, all this may increase the impact of cocaine, although perhaps the economic costs could go in the opposite direction.
In cost analyses, it is also necessary to take into account previous visits to the emergency department by these patients, with the resulting health care expense or cost associated with cocaine consumption. Other elements to consider are cases of sudden death in the out-of-hospital setting9 and repeat emergency department visits.10 Lastly, since the study covered a 3-year period, some patients probably experienced more than one coronary ischemic event requiring hospital readmission.11
Finally, we agree with Gili et al that interventions aimed at identifying the risks associated with the use of these substances and the treatment of addiction are essential for the prevention of recurrence of cardiovascular events in this patient group, and an important part of the hospital stay should be devoted to these aims, although it may prolong hospitalization.10