Cocaine use and the likelihood of cardiovascular and all-cause mortality: data from the Third National Health and Nutrition Examination Survey Mortality Follow-up Study.

BACKGROUND

Numerous case series have implicated cocaine use as a cause of both myocardial infarction (MI) and stroke on the basis of the temporal relationship between drug use and event onset. The relatively high prevalence of cocaine use in the US population, especially in younger individuals, mandates a more extensive investigation of this relationship.

METHODS

We determined the relationship between cocaine use and cardiovascular and all-cause mortality in a nationally representative sample of 9013 US adults aged 18 to 45 years who participated in the Third National Health and Nutrition Examination Survey Mortality Follow-up Study using Cox proportional hazards analyses. We categorized the participants as nonusers if they responded to the lifetime cocaine use question as never used, as infrequent users if they responded as using <10 times, and as frequent or regular users if they reported using 10-99 times or >100 times, respectively. Potential confounding factors in the association between cocaine use and death (cardiovascular and all cause) included age, sex, race/ethnicity, cigarette smoking, hypertension, diabetes mellitus, hyperlipidemia, educational attainment, body mass index, and insurance status. To estimate the impact of cocaine use on MI or stroke, we calculated the population attributable risk (PAR) percent for cocaine use with cardiovascular and all-cause mortality. We also estimated the years of life lost and total annual financial cost due to premature deaths in persons who reported regular use of cocaine.

RESULTS

A total of 60 cardiovascular deaths and 384 all causes deaths were reported during a mean follow-up period of 14.7 ± 2.6 years. After adjusting for differences in potential confounders, persons who reported regular lifetime cocaine use had a significantly higher likelihood of all-cause mortality (relative risk [RR], 1.9; 95% confidence interval [CI], 1.2-3.0 for ≥100 times in lifetime) but not cardiovascular mortality (RR, 0.6; 95% CI, 0.1-4.7 for ≥100 times in lifetime). The PAR of regular cocaine use for all cause mortality among was 1.79%. The years of life lost due to regular cocaine use was 10.3 years for an adult aged 31 years. The overall yearly cost incurred due to premature deaths related to regular cocaine use was $1.1 billion.

CONCLUSION

Regular cocaine use was associated with an increased risk of all cause mortality but this effect was not mediated through cardiovascular events. Behavior modification by public awareness and education may reduce the mortality and financial burden associated with cocaine use.