More than 20% of persons aged 65 years and older in 2001-2002 reported having a substance use disorder during their lifetimes and most of them had an alcohol use disorder. Alcohol, tobacco, and non-medical drug use disorders were more likely in those who were younger, male, or divorced or separated. More than 5% reported having any substance use disorder in the past 12 months, and most of them had a tobacco use disorder. Less than 1% reported having a disorder involving non-medical use of drugs. Other individual or combined disorders occurred in less than 0.5% in this population. These rates are similar but higher than the prevalence rates observed in the 2002 National Survey on Drug Use and Health (NSDUH), another large nationally representative survey on overall substance use patterns and correlates.31
Among the sample of 2,019 adults aged 65 years and older surveyed in the 2002 NSDUH, the past 12-month prevalence rate of alcohol abuse or dependence was 1.1%, past 12-month illicit drug abuse or dependence was <0.1%, and past month nicotine dependence was 3.9%. The discrepancies between the two data sets have been attributed to factors related to privacy and anonymity, and differences in substance use disorder diagnostic instrumentation.32
Consistent with other studies, the prevalence rates of these disorders in older adults were lower compared to the general adult population.1-9
Among general U.S. adult population, lifetime prevalence of alcohol use disorder was approximately 18%,6, 33
tobacco dependence was 25%,34, 35
and drug use disorders were reported to be 8%.8, 36
Rates of past year alcohol use disorder among U.S. adults ranged from 5-7%,6, 37
tobacco dependence ranged from 15-20%,35, 38
and drug use disorders were approximately 2%.8, 36
In terms of the overlap of disorders involving different substances, other studies have found that combined past year alcohol and tobacco disorders occurred in approximately 3% of the adult population,4
and combined past year alcohol and drug use disorders occurred in approximately 1% of the population.7, 39
Our analyses highlighted that alcohol and tobacco were the two most common substance use disorders among older adults in 2001-2002, and although alcohol use disorder was the most common lifetime substance use disorder, tobacco use disorder was the most common substance use disorder in the past year for older adults. Although the prevalence of substance use disorders among older adults are lower than the younger adult population, a recent study using the 2005-2006 NSDUH found that among older adults ≥65 years, 13% of men and 8% of women reported at-risk drinking (≥2 drinks per day), and 14% of men and 3% of women reported binge drinking (≥5 drinks on one occasion).40
These results suggested a much higher prevalence of risky alcohol use among older adults, which could potentially lead to future development of abuse and dependence.
The prevalence of substance use disorders declines with increasing age, likely in part due to maturing out of abuse and dependence, but also due to increased mortality among those who had substance use disorders compared to those without such disorders.5, 41-43
Another reason for reduced prevalence of substance use disorders in older adults, compared to the younger population, is that such disorders are often under-detected or reported.44-46
Symptoms of substance abuse may be attributed to other problems common in older adults such as cognitive impairment, depression, weight loss, and gastrointestinal conditions. Older adults are also more likely than younger adults to conceal substance abuse problems and fail to seek help.22
Older adults are the group most prescribed psychoactive drugs with abuse potential, including sedatives and opioids,17, 47
which makes non-medical drug use disorder a potential concern in this group. However, our study found a low prevalence of drug use disorder among older adults. A study using 2005-2006 NSDUH to evaluate drug use in older adults also found only 0.33% met criteria for drug abuse or dependence; however, almost 4% of those in the 50-64 age group used marijuana, suggesting the prevalence of illicit drug use among older adults may increase in the future as the younger cohort ages.48
While we observed relatively few sociodemographic correlates of each of the substance use disorders examined, there were some consistent findings. The strongest correlates of substance use disorders among older adults were younger age, male gender, and being divorced or separated. Younger persons were more likely than older persons, and divorced or separated persons were more likely than married persons to report having an alcohol, tobacco, or non-medical drug use disorder over their lifetimes. Furthermore, men were more likely than women to have lifetime alcohol and tobacco use disorders and past 12-month alcohol use disorder, and those with very good or excellent health status were less likely than those with poor health to have both lifetime and past 12-month tobacco use disorders. Similar correlates have also been observed in general adult populations.4, 6-8, 34, 36, 39, 49
Limitations of this study included our restricted ability to fully examine the sociodemographic and health-related correlates of non-medical drug use disorder due to small sample sizes. Also, it is possible that rates of all three substance use disorders reported in this older cohort may be lower than expected because of premature mortality among those who had these disorders. The ability to examine associations of substance use disorders and sociodemographic and health-related correlates among older adults will likely increase as the Baby Boomer generation ages and the number of persons reporting substance use disorders increases.13
Recall bias and social undesirability of reporting a substance use disorder, particularly among women and some ethnic groups, may also have contributed to under-reporting. The cross-sectional design of this study was another limitation, but data from the 3-year follow-up of NESARC participants will enable us to evaluate longitudinal patterns and sociodemographic and health-related correlates of substance use disorders in future studies. Also, longitudinal data will enable future evaluation of patterns of relapse and remission of substance use problems among older adults. Finally, these findings were only descriptive of the non-institutionalized U.S. older adult population in 2001-2002, and other studies need to examine the rates and correlates of substance use disorders in older populations in more recent years, in other countries, and among those who are institutionalized including those in prison, where substance use disorders are likely to be higher, and assisted living and skilled nursing facilities where they are likely to be lower.
In summary, data from NESARC, a large population-based study of older adults addressing substance use disorders, indicated that more than 1 in 5 older adults had a substance use disorder in the past, primarily involving alcohol or tobacco. In addition, 5% of older adults met DSM-IV criteria for a past 12-month substance use disorders, primarily due to tobacco followed by alcohol. Very few older adults endorsed criteria for non-medical drug use disorders. Similar to findings in the general adult population, younger persons in this older cohort were more likely than older persons to report any type of substance use disorders. Furthermore, men were more likely than women to report alcohol or tobacco use disorders, a finding also observed in younger populations.
These data contribute to our understanding of alcohol, tobacco, and non-medical drug use disorders in the growing population of older adults in the U.S., and suggest that healthcare providers should ask older adults more regularly about use and be aware of clinical signs and symptoms of substance use disorders. If older adults who use these substances in a harmful way are more frequently identified, they can be offered interventions to reduce substance-associated morbidity, thereby improving overall quality of life and reducing health care costs.