Alcohol and Tobacco Use : Prevalence

by National Institute of Health

(Page 2 of 3)

Researchers used the NHSDA data gathered between 1995 and 1997 to estimate the prevalence of recent use of alcohol and/or tobacco. The researchers analyzed the data for all age groups, either for all respondents or separately by gender.

Alcohol Use

With respect to alcohol use, the youngest respondents already showed a relatively high prevalence of recent use. Thus, 45 to 55 percent of these adolescents had consumed alcohol at least once during the past year. The prevalence of alcohol use was highest among young adults ages 25 to 34, of whom approximately 80 percent had used alcohol during the past year. Among respondents age 35 and older, the prevalence of alcohol use generally declined in a linear fashion with increasing age. In 1 of the 3 survey years, however, an intriguing increase in alcohol consumption was noted in men ages 55 to approximately 70. Although this "uptick" in the curve may simply reflect some statistical instability, the variation may merit a more detailed investigation (to assess its potential association with retirement or bereavement). Overall, however, alcohol use prevalence among the oldest respondents was similar to that observed during late adolescence. Moreover, with the exception noted here, differences in the prevalence of alcohol consumption between men and women generally were moderate.

Tobacco Use

The NHSDA similarly estimated the prevalence of recent tobacco smoking in various age groups of the population. These estimates show a pattern similar to that noted for recent alcohol consumption. Thus, prevalence rates were lowest among young adolescents (approximately 10 percent among 12-year-olds) but increased sharply during the adolescent

and young-adult years, reaching peak values (approximately 45 to 50 percent) among young adults. Subsequently, a generally linear decline in smoking prevalence occurred among respondents from approximately age 30 to the oldest age groups. As a result, the oldest survey respondents were just as likely as teenagers were to have smoked tobacco in the past year.

Only moderate differences in smoking prevalence existed between male and female survey respondents. The patterns of age-specific prevalence rates also generally were congruent for both genders.

Concurrent Alcohol and Tobacco Use

The NHSDA allowed researchers to estimate the numbers of people in the U.S. population who had consumed both alcohol and tobacco during the year before the survey was conducted. The analyses found that among the youngest and oldest respondents, approximately 10 to 15 percent of both men and women had consumed both alcohol and tobacco within the past year. Among the young adults, the prevalence of recent concurrent alcohol and tobacco use was approximately 35 to 45 percent. These estimates and their age-specific patterns indicate that a majority of the recent tobacco smokers had also consumed alcohol, whereas the proportion of recent alcohol consumers who had also smoked tobacco recently was smaller.

Prevalence of Alcohol and Tobacco Dependence

Dependence Rates Among Alcohol and Tobacco Users

For some people, initial occasional consumption of alcohol and/or tobacco leads to the development of the clinical syndromes of alcohol and/or tobacco dependence. For example, according to the NCS estimates for 15- to 54- year-old U.S. residents, approximately 15 percent of alcohol users had become alcohol dependent and approximately 32 percent of tobacco users had become tobacco dependent.

In order to examine the salience of alcohol and tobacco dependence as determinants of continued alcohol and tobacco consumption among the population, epidemiologists have analyzed data from the NCS to estimate the proportion of recent alcohol and tobacco users who were alcohol and tobacco dependent.

Based on the DSM - III - R criteria, an estimated 10 to 30 percent of recent alcohol consumers ages 15 to 24 were designated as alcohol dependent. With increasing age, the prevalence of alcohol dependence among recent users declined almost linearly.

The age-related pattern for tobacco dependence differed from the pattern for alcohol dependence. For example, unlike alcohol dependence, tobacco dependence was lowest among the youngest tobacco smokers. The prevalence of tobacco dependence increased to approximately 25 to 35 percent among young adult smokers and remained high (approximately 25 percent) before it declined again among the oldest segment of the study population.

Finally, the NCS assessed the respondents' concurrent alcohol and tobacco dependence in the year preceding the survey interview. As with the estimated prevalence rates for tobacco dependence, concurrent alcohol and tobacco dependence appeared to be less prevalent among 15- to 18-year-old users than among older adolescent and young adult users (approximately 10 percent among 21- to 25-year-olds).

The variation in age-specific prevalence of alcohol dependence and tobacco dependence is particularly pronounced among female alcohol and tobacco users. Thus, alcohol dependence is more prevalent among young-adult female drinkers (approximately 20 to 25 percent) than among adolescent and older female drinkers (approximately 10 percent or less). For tobacco, however, women around age 40 who smoke are almost as likely to be tobacco dependent (approximately 25 percent) as are young adult women. Conversely, adolescent female smokers have lower rates of tobacco dependence (less than 20 percent). Concurrent alcohol and tobacco dependence affects approximately 8 to 10 percent of young female smokers, with a subsequent linear decline. These values are slightly lower than those observed among male alcohol and tobacco users, in whom dual dependence prevalence peaks at approximately 14 percent at ages 22 to 25.

Dependence Rates in the Entire Population

The NCS data also provided estimates of the prevalence of dependence on alcohol and tobacco in the population at large (considering both consumers and nonconsumers of both drugs). When all age groups were combined, the NCS data indicated that approximately 14 percent of 15- to 54-year-olds in the United States had become alcohol dependent and approximately 24 percent of people in those age groups had become tobacco dependent. Accordingly, if alcohol dependence and tobacco dependence occurred together only by chance, one would expect approximately 3.4 percent of the study population (24 percent of 14 percent) to be both alcohol and tobacco dependent. In fact, however, the NCS found the prevalence of concurrent alcohol and tobacco dependence to be approximately twice as high, suggesting a need for research on mechanisms that may contribute to co-dependence on both drugs.

About the Author

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