of current nicotine dependence is greate r among Native American and Alaska Natives
(23%) than among whites (14%) but is less am ong African Americans (10%), Asian Amer-
icans and Pacific Islanders (6%), and Hispan ics (6%). The prevalence among current daily
smokers is approximately 50%.
In many developing nations, the prevalence  of smoking is much greater in males than
in females, but this is not the case in develope d nations. However, ther e often is a lag in the
demographic transition such that smoking increases in females at a later time. 
Development and Course
The majority of U.S. adolescents experiment with tobacco use, and by age 18 years, about
20% smoke at least monthly. Most of these in dividuals become daily tobacco users. Initi-
ation of smoking after age 21 years is rare. In general, some of the to bacco use disorder cri-
teria symptoms occur soon after beginning to bacco use, and many individuals’ pattern of
use meets current tobacco use diso rder criteria by late adolescence. More than 80% of in-
dividuals who use tobacco atte mpt to quit at some time, but 60% relapse within 1 week
and less than 5% remain abstinent for life . However, most indivi duals who use tobacco
make multiple attempts such that one-half of  tobacco users eventually abstain. Individuals
who use tobacco who do quit usually do not do  so until after age 30 years. Although non-
daily smoking in the United States was previ ously rare, it has beco me more prevalent in
the last decade, especially among younger individuals who use tobacco. 
Risk and Prognostic Factors 
Temperamental. Individuals with externalizing pers onality traits are more likely to