Columbia: While cigarette smoking has long been on the
decline, marijuana use is on the rise and, disproportionately, marijuana
users also smoke cigarettes. A new study by researchers at Columbia University’s Mailman School of Public Health and
the City University of New York reports that cannabis use was
associated with an increased initiation of cigarette smoking among
non-cigarette smokers. They also found adults who smoke cigarettes and
use cannabis are less likely to quit smoking cigarettes than those who
do not use cannabis. Former smokers who use cannabis are also more
likely to relapse to cigarette smoking. Results are published online in
the Journal of Clinical Psychiatry.
Until
now, little was known about the association between cannabis use and
smoking cessation or relapse over time in the general adult population.
The
analyses were based on data from the National Epidemiologic Survey on
Alcohol and Related Conditions in 2001–2002 and 2004–2005, and responses
from 34,639 individuals to questions about cannabis use and smoking
status.
“Developing a better understanding of the relationship
between marijuana use and cigarette use transitions is critical and
timely as cigarette smoking remains the leading preventable cause of
premature death and disease, and use of cannabis is on the rise in the
U.S.,” said Renee Goodwin, PhD, in the Department of Epidemiology at the Mailman School of Public Health, and senior author.
The
study suggests that marijuana use—even in the absence of cannabis use
disorder (characterized by problematic use of cannabis due to impairment
in functioning or difficulty quitting or cutting down on use)—is
associated with increased odds of smoking onset, relapse, and
persistence. As cannabis use is much more common than cannabis use
disorder, its potential impact on cigarette use in the general community
may be greater than estimates based on studies of cannabis use disorder
alone, according to the researchers.
An earlier study by Goodwin and
colleagues showed that the use of cannabis by cigarette smokers had
increased dramatically over the past two decades to the point where
smokers are more than 5 times as likely as nonsmokers to use marijuana
daily.
Goodwin advises that additional attention to cannabis use
in tobacco control efforts and in clinical settings aimed at reducing
cigarette smoking and smoking related negative consequences may be
warranted. She also points out that understanding the potential links
between cannabis use and cigarette initiation in youth is needed given
that recent data suggest cannabis use is more common among adolescents
than cigarette use.
Co-authors include Andrea H. Weinberger,
Albert Einstein College of Medicine; Jonathan Platt, Mailman School of
Public Health; and Jan Copeland, National Drug and Alcohol Research
Centre, University of New South Wales Medicine, Sydney, Australia.
The
study was supported by National Institutes of Health/National Institute
on Drug Abuse, (grant DA20892). The authors reported no financial
conflicts.