A systematic review of evidence on the association between cocaine use and seizures.
BACKGROUND
Institutional monographs/medical textbooks mention seizures as a neurological complication of cocaine, but no systematic reviews (SRs) have been published on this issue. We aimed to conduct a SR of the literature on the relationship between cocaine use and seizures and to summarize the biological plausibility of that relationship.


METHODS
The pathophysiological mechanisms that may underlie an association between cocaine and seizures were summarized; a SR was then performed using three databases (EMBASE, Medline, PsycINFO) and the Cochrane-library to search for published papers (1980-2012) aimed at quantifying the associations between cocaine use and seizures. The inclusion criteria for selection were: articles based on clinical trials, cohort, case-control (CC) or cross-sectional (CS) studies, participants ≥ 14 years old and not pregnant, and use of cocaine in the last 72 h. Information was extracted, evaluated and cross-checked independently by two researchers.


RESULTS
Of the 1243 potentially relevant articles initially identified; one CC and 22 CS studies were finally selected. The CC study did not find cocaine use to be a risk-factor for seizures. In addition to the limitations of the CS design, these studies had important methodological weaknesses and biases.


CONCLUSIONS
Despite its biological plausibility, no rigorous scientific evidence supports a causal relationship between cocaine use and seizures. The misinterpretation of the role of cocaine may have important implications in medical services. Well-conducted studies are urgently needed.
National Centre of Epidemiology, Carlos III Health Institute, Madrid, Spain; Department of Preventive Medicine and Public Health, Faculty of Medicine, Complutense University, Madrid, Spain; Network Biomedical Research Centers, Epidemiology and Public Health (CIBERESP in Spanish), Spain. Electronic address: lsordo@isciii.es.
L
L
Sordo
B I
BI
Indave
L
L
Degenhardt
G
G
Barrio
S
S
Kaye
I
I
Ruíz-Pérez
M J
MJ
Bravo
D001921:Brain / Q000187:drug effects; D003042:Cocaine / Q000633:toxicity*; D019970:Cocaine-Related Disorders / Q000150:complications*; D006801:Humans; D012640:Seizures / Q000139:chemically induced / Q000150:complications*
D003042:Cocaine
Cocaine use; Neurologic disorder; Seizures; Systematic review