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The Gerontologist cite as: Gerontologist, 2017, Vol. 00, No. 00, 1–7 doi:10.1093/geront/gnw166 Advance Access publication January 11, 2017

Policy Studies

The Increasing Use of Cannabis Among Older Americans: A Public Health Crisis or Viable Policy Alternative? Brian Kaskie, PhD,* Padmaja Ayyagari, PhD, Gary Milavetz, PharmD, Dan Shane, PhD, and Kanika Arora, PhD Department of Health Management and Policy, College of Public Health, University of Iowa. *Address correspondence to Brian Kaskie, PhD, Department of Health Management and Policy, College of Public Health, University of Iowa, 105 N River Street, N214, Iowa City, IA 52242. E-mail: [email protected] Received June 7, 2016; Editorial Decision date October 11, 2016 Decision Editor: John B. Williamson, PhD

Abstract Cannabis use among older Americans is increasing. Although much of this growth has been attributed to the entry of a more tolerant baby boom cohort into older age, recent evidence suggests the pathways to cannabis are more complex. Some older persons have responded to changing social and legal environments and are increasingly likely to take cannabis recreationally. Other older persons are experiencing age-related health care needs, and some take cannabis for symptom management, as recommended by a medical doctor. Whether these pathways to recreational and medical cannabis are separate or somewhat tangled remains largely unknown. There have been few studies examining cannabis use among the growing population of Americans aged 65 and older. In this essay, we illuminate what is known about the intersection between cannabis and the aging American population. We review trends concerning cannabis use and apply the age–period–cohort paradigm to explicate varied pathways and outcomes. Then, after considering the public health problems posed by those who misuse or abuse cannabis, we turn our attention to how cannabis may be a viable policy alternative in terms of supporting the health and well-being of a substantial number of aging Americans. On the one hand, cannabis may be an effective substitute for prescription opioids and other misused medications; on the other hand, cannabis has emerged as an alternative for the undertreatment of pain at the end of life. As intriguing as these alternatives may be, policy makers must first address the need for empirically driven, representative research to advance the discourse. Keywords: Alternative and complementary medicine/care/therapy, Health care policy, Medications/prescriptions/OTC drugs/pharmacology, Pain management, Public policy

Cannabis use among persons older than 50 years has increased significantly, exceeding projections and outpacing the recent growth observed across all other age groups (Substance Abuse and Mental Health Services Administration, 2014). In 2000, past-year cannabis use among all persons older than 50 years was estimated as 1.0%, with rates reaching 2.0% among those aged between 50 and 59 years (i.e., the baby boomers). Projecting to the year 2020, use rates among those older than 50 years were expected to climb to 2.9%, largely as a function of the continued aging of a baby boom cohort with historically

higher rates of lifetime use (Colliver, Compton, Gfroerer, & Condon, 2006). However, when analyzing the 2008 National Survey of Drug Use and Health (NSDUH), DiNitto and Choi (2011) found past-year cannabis use for all persons older than 50 years already had reached 2.8%. When NSDUH data from 2008 through 2012 were pooled, Choi, DiNitto, Marti, and Choi (2015) found past-year cannabis use climbed to 3.9%. Using another nationally representative survey, the 2014 Summer Styles Consumer Panel Survey, Schauer, King, Bunnell, Promoff, and McAfee (2016) found that 5.1% of

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persons older than 50 years reported taking cannabis in the past month, suggesting use rates might be higher than indicated by the NSDUH data. Schauer and colleagues (2016) also reported that among all current cannabis users (including those older than 50 years), 10.5% reported medicinal-only use, 53.4% reported recreational-only use, and 36.1% reported both. In comparison to the NSDUH, these estimates were generated from a small subpopulation of older adults who were not recruited from a populationbased probability sample. Schauer and colleagues also did not stratify reasons for use by age (Figure 1). Although this prior work has been illuminating, policy makers have only been offered glimpses into this imminent public health challenge. Several substantive gaps exist in what is currently known about cannabis and older persons. What are the self-reported antecedents of taking cannabis? Does cannabis use lead to substance misuse or prescription substitution? As the United States is about to enter a period when the older adult population is projected to double (Ortman, Velkoff, & Hogan, 2014) and the cannabis economy may grow fivefold (Caulkins, Kilmer, Reuter, & Midgette, 2015), such critical questions need to be asked. Yet, at this time, there have been few directions charted for conducting the kind of research that would be most useful in providing empirically based answers. In this analytic essay, we apply the age–period–cohort paradigm to explore the intersection between cannabis and older persons. We consider how cannabis use among older adults is being shaped variably by social attitudes, state laws, and individual characteristics, such as health needs and prescription drug use, and rely on previous data analyses as well as original data collected from eight state medical cannabis programs to chart the different paths older adults are taking. We consider undesirable outcomes such as the misuse and abuse of cannabis. We then direct our attention to two other prominent public health issues, one concerning the increasing misuse of prescription medications (e.g., opioids) and the other focusing on the undertreatment of pain at the end of life, and consider how cannabis substitution may be a viable policy alternative to these more prominent public health problems.

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Antecedents of Cannabis Use Among Persons Older Than 50 Years The majority of persons older than 50 years who currently take cannabis are healthy and white, though there are several significant individual differences among the population of nearly 45 million older Americans (Choi et al., 2015; Colliver et al., 2006; DiNitto & Choi, 2011). The NSDUH data indicated that older persons who currently take cannabis were statistically more likely to have started taking cannabis before the age of 30 years, with many starting before the age of 18 years. These persons who initiated cannabis use before the age of 30 years make up half of all those older than 50 years who used it recently, and nearly a quarter of these consistent users took cannabis at least 3–4 times per week in the past year. Past-year cannabis use also has been associated with gender (men are more likely to use than women), marital status (those who are not married are more likely to use), and race (non-whites are more likely to use than whites). Persons older than 50 years who take cannabis are more likely to smoke cigarettes, drink alcohol, and use cocaine and other illicit drugs including opioids. The majority of all persons older than 50 years who took cannabis in the past year indicated they used less than once every 10 days, and 25% of all older persons used less than five times during the past year (Blazer & Wu, 2009). More than 9 out of 10 of all older persons who took cannabis in the past year reported having no emotional or functional problems, and the majority indicated they placed no self-limit on their use (Black & Joseph, 2014). Only 2.0% of persons older than 50 years indicated they have been diagnosed as having abused cannabis in their lifetime, and only 0.9% have ever received professional treatment for taking cannabis, though 20.7% individuals who used in the past year reported seeking treatment for alcohol or some other substance besides cannabis at some point in their life (Blazer & Wu, 2009; Wu & Blazer, 2011). Although there is reason to be concerned that increasing cannabis use among older persons may contribute to increased rates of substance misuse or other undesirable outcomes such as overdoses and traffic accidents, the overwhelming majority of older adults do not experience negative outcomes. In fact, an increasing number of reports have highlighted the benefits that older persons derive when taking cannabis (Ahmed, van den Elsen, van der Marck, & Rikkert, 2015).

Charting the Pathways Between Cannabis and Older Persons

Figure 1. Past-year cannabis use by age group.

One way to illuminate the growing intersection between cannabis use and United States’ aging population is to deploy a paradigm in which individual outcomes (e.g., taking cannabis) are assumed to be shaped by cohort effects (e.g., more favorable attitudes held by one generation but not another) as well as period effects (e.g., historical events such as cannabis legalization) and age effects that


Figure 2. Pathways to cannabis use among older adults.

occur over the life course (e.g., health problems). O’Malley, Bachman, and Johnston (1988) originally applied this perspective to examine the dynamic changes in cannabis use among nationally representative panels of high school seniors who graduated between 1976 and 1986 (Figure 2). In trying to understand why cannabis use increased and then decreased among succeeding graduating classes, they referred to a period effect. In particular, O’Malley and his colleagues attributed the decreasing cannabis use among seniors graduating after 1981 to national efforts to curtail illegal drug use initiated by the Reagan administration. O’Malley and his colleagues then linked the consistent decreases in cannabis use after the age of 21 years to maturation (age effect) and argued that taking cannabis declines as individuals assume more professional and personal responsibilities. Other researchers (e.g., Miech & Koester, 2012) have since deployed the age–period–cohort paradigm to examine contemporary patterns of cannabis use among nationally representative panels, but little effort has been made to analyze the pathways associated with varied cannabis use among older persons.

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O’Malley et al.), the boomers’ positive attitudes toward cannabis have been increasing steadily ever since. By 2000, as the leading edge of the baby boom cohort reached and surpassed their 50th birthdays, 34% were in favor of legalizing cannabis (Black & Joseph, 2014). Other researchers have found that as general public opinion about cannabis has become less negative, older individuals have become more likely to adopt favorable attitudes (Schuermeyer et al., 2014). Changing attitudes among older adults also have been tied to perceptions about the medical benefits of cannabis. Kalata (2004) reported that nearly 60% of persons over the age of 45 years believed cannabis provided a medical benefit and 72% believed doctors should be allowed to recommend medical cannabis. Although such attitudes were higher among those who previously had taken cannabis, nearly two out of every three who never took cannabis at any point during their life also held such favorable attitudes about medical benefits. Wang and Chen (2006) suggested that such attitude changes can occur when a person assigns a higher degree of relevance to an issue. In this case, when facing a health crisis, an older adult may be more likely to engage in processing new information that ultimately may alter a long-standing attitude about how to treat the health problem. For example, suppose some older person who historically has held negative attitudes toward cannabis begins to suffer with intractable pain. As the pain progresses and remains inadequately treated, the older adult may receive information about the potential benefits of taking cannabis from a patient advocacy organization such as the ALS (Amyotrophic Lateral Sclerosis) Foundation. The older patient may then inquire of his or her physician if cannabis may provide some sort of benefit. This sort of information processing reflects how a long-held attitude about cannabis can be altered. In 2014, favorable attitudes among aging baby boomers reached 52%, and Black and Joseph linked these increasingly more favorable views with increasing rates of pastyear use among those older than 50 years. In 2000, the percentage of older persons who had tried marijuana at least once in their lifetime reached 23% among 50–64 year olds and 3% among those aged 65 and older. By 2011, lifetime usage rates increased to 44% among those between 50 and 64 years old and 17% for persons older than 65 years (Black & Joseph, 2014).

Cohort Effects According to social learning theory, individual attitudes are developed through social interactions and are maintained through conditioning, imitation, and reinforcement (Black & Joseph, 2014). Persons born between 1946 and 1964 have consistently held more favorable attitudes toward legalizing cannabis than persons born prior to 1945 (e.g., the silent generation born between 1925 and 1945). By the time these “baby boomers” graduated from high school, 43% held the opinion that marijuana should be legalized (Black & Joseph, 2014). Although such favorable attitudes toward legalization dropped to 17% in 1990 (reflecting the period effect associated with the Reagan administration, as identified by

Period Effects Another perspective suggests the decision to take cannabis is based on subjective calculations concerning reward and risk (Black & Joseph, 2014). Individuals living in states with medical marijuana laws (MMLs) may perceive less risk in taking cannabis and, thus, increase their use. Although most studies linking past-year use rates with states that have taken some step toward legalizing cannabis have focused on younger populations, we did find a few that offered some insight into whether the introduction of MMLs had an effect on older persons. Using data from the 2004 National Epidemiologic Survey of Alcohol and Related


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conditions as well as the 2004 NSDUH, Cerdá, Wall, Keyes, Galea, and Hasin (2012) identified significant statistical differences in past-year use rates between those living in states with and without MMLs, and these persisted across all age groups. A more recent study by Wen, Hockenberry, and Cummings (2015) pooled NSDUH survey data from 2004 through 2012 and contrasted past month cannabis use rates within those states that adopted MMLs during this period with those that did not. They found that, among all persons older than 21 years, the introduction of an MML corresponded with significant increases in past-month cannabis use. Given the lack of significant differences between younger and older adults, we surmised that persons older than 50 years living in MML states were just as likely as younger persons to have increased their past-year use. Because the NSDUH survey only asks about the illegal use of cannabis, we retrieved registry data from eight state programs to determine whether older adults were using legalized medical cannabis as well. In analyzing the multiyear population summary data presented by four of these states, we found the total number of older program participants has been increasing steadily in the last 5 years, and persons older than 60 years are representing a greater portion of the state program population. In Montana, 680 persons older than 60 years registered for the state medical cannabis program in 2010, representing 7.9% of all program participants; by 2015, the number of older participants grew to 2,037 and persons older than 60 years represented 19.3% of all program participants. In Arizona, the number of state program participants over the age of 60 years totaled 7,191 in 2013 and represented 16.7% of the registry; by the end of 2015, the number reached 14,680 and persons older than 60 years constituted 18.9% of registered participants. The Colorado registry data revealed that participants older than 60 years totaled 17,495 in 2014 and increased to 17,877 in 2015. The other state program registries only recently began collecting patient data and the proportion of older users ranged from 9.9 to 20.5% of all participants. States in which cannabis has been approved for recreational purposes do not compile such data (Figure 3).

Figure 3. State programs by approved conditions.

We suspect the total number and proportion of older users might be even greater in those states in which efforts to implement medical cannabis programs are more extensive. In particular, although the majority of states have moved to legalize cannabis in the past decade, the scope of these state laws and related implementation efforts vary considerably (Pacula, Hunt, & Boustead, 2014). Some states allow recreational use as well as medicinal use for a wide range of conditions, other state laws and dispensary operations are more restrictive. Pacula, Powell, Heaton, and Sevigny (2015) found that MMLs vary across no fewer than four substantive dimensions, and increased use of cannabis has been associated with factors such as whether the state allows for individual cultivation.

Age Effects As persons become older, they may experience stressful events such as the loss of a spouse or a lack of sufficient retirement income, and these age-related events may lead them to take cannabis as a coping mechanism (Black & Joseph, 2014). As persons age, the chances of acquiring a disease or disability that are possibly amenable to medical cannabis also increase considerably. For example, glaucoma refers to a constellation of age-related ocular conditions that constitute the primary cause of blindness among persons older than 65 years. Several researchers have reported that medical cannabis successfully reduces glaucomarelated ocular pressure and can help prevent blindness, and the use of medical cannabis for glaucoma is supported by the American College of Physicians (2008). Another set of age-related conditions considered amenable to medical cannabis include cachexia (or wasting syndrome), nausea, and other diagnosable conditions associated with cancer. The National Cancer Institute (2016) indicated that medical cannabis can successfully stimulate appetites and be helpful for patients who experience nausea and pain. Neurologic diseases also are considered amenable to medical cannabis; the American Academy of Neurology (Patel et al., 2014) supports the use of oral cannabis to improve symptoms among persons with multiple sclerosis. We determined that up to 21 states have approved the use of medical cannabis for such age-related diagnosable conditions (Marijuana Policy Project, 2016). In reviewing registry data for patients older than 65 years in Colorado, glaucoma was the primary condition assigned to 3.6% of older program registrants. (Note: Colorado is the only state that offered data by age and condition.) We found cachexia was diagnosed among 1.6% of the registrants, 5.7% had nausea, and 10.8% were identified as having cancer. The age-related neurologic conditions that are covered by state programs include amyotrophic lateral sclerosis (covered in nine states), muscular dystrophy (two states), and Parkinson’s disease (three states), and 15.9% of those older than 65 years in Colorado were diagnosed with one of these. Eight states have extended coverage to


persons with Alzheimer’s disease (N = 8), and three states have approved cannabis for persons receiving palliation or hospice. In Montana, 14 people obtained medical cannabis to help navigate the end of life in 2015. Still, by far, the primary application of medical cannabis has been to alleviate pain, generally defined as central and peripheral neuropathic pain or more specifically as nociceptive pain associated with a particular condition (Erickson & Kiser, 2016). We determined 19 states have approved the provision of medical cannabis for persons diagnosed with symptoms of pain and, in reviewing the patient registry data, 89.7% of those older than 65 years in the Colorado program had listed pain as a primary or secondary condition. In an independent study of persons who enrolled in a Michigan medical cannabis program, Illgen and his colleagues found that 87% of new program participants were looking to relieve symptoms of pain. They also found that 27% of these newly enrolled patients were older than 50 years, and 79% of these older participants never used cannabis before (Ilgen et al., 2013). In linking the state registry data with the number of approved conditions, it was apparent that states with higher participation rates among older adults had approved the use of cannabis for a greater number of age-related conditions including neuropathic pain. As more states look to legalize medical cannabis and expand the menu of qualified conditions, we suspect the number of older adults who take cannabis should increase substantially as perceived medical need appears to be a prominent starting point for those who take cannabis for the first time since they were younger or for the first time ever (Figure 4). Moreover, the Institute of Medicine (1999) and American College of Physicians (2008) have endorsed the use of medical cannabis for a limited number of age-related conditions, and such endorsements appear to be having an impact on the perceptions of medical doctors and other health care providers. In a survey of 1,446 readers of the New England Journal of Medicine, Adler and Colbert (2013) found that

Figure 4. State program participation among older adults.

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76% supported the use of medical cannabis in a case study in which an older woman was diagnosed with metastatic cancer and suffering with nausea and pain. Although several other provider organizations (e.g., American Medical Association, American Nurses Association, American Pharmacists Association) have stopped short of endorsing the use of medical cannabis, they all have called for more public education and training of their provider constituencies with particular emphasis being placed on differentiating the legal risks associated with a doctor prescribing cannabis (i.e., a FDA violation) relative to the risks of a doctor recommending it (i.e., as protected by free speech). Arguably, as medical doctors and other allied health professionals become more educated about the potential uses of medical cannabis and how to communicate this information legally, they may be more likely to recommend cannabis for some of their older patients. As suggested earlier, such authoritative cues may alter patient attitudes about taking medical cannabis, particularly among those who historically had not supported cannabis legalization or may continue to disapprove of taking cannabis for recreational purposes.

Cannabis, Opioids, and End of Life Much of the previous work concerning cannabis use among older persons has pointed to negative outcomes. As more older persons take cannabis, the number of those who abuse or become dependent will increase; as more older adults abuse or become dependent on cannabis, they will place a greater demand on specialty service providers (Blazer & Wu, 2009; Wu & Blazer, 2011). Although these studies present valid public health concerns that already have captured the attention of policy makers and public officials, the use of cannabis among older adults also should be juxtaposed to the potential benefits. For example, some older adults are taking cannabis as a viable substitute or complement for addictive and potentially harmful prescription medications. Lucas and colleagues (2012) found that among 404 registered participants from 4 Canadian compassionate care clubs (i.e., authorized cannabis dispensaries), 67.8% took cannabis as a substitute for prescription medication. In a followup, 80% of another sample of 473 club members reported substituting cannabis for prescribed pharmaceutical medications. These substitutions occurred most often among persons experiencing pain (87%), and the primary reasons for doing so was to decrease side effects and improve symptom management (Lucas et al., 2015). Increased access to medical cannabis also has been linked with a reduction in negative outcomes associated with opioid use. In contrast to the number of opioid overdoses within states with and without MMLs, Smart (2015) found that opioid related deaths increased across all states, but such deaths were 25% less likely to occur in those states with MMLs and opioid deaths specifically were less


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common among older persons. Given that West, Severtson, Green, and Dart (2015) reported that the rate of prescription opioids is highest among women older than 60 years (8.6% compared with 4.7% for those aged 20–39 years), such findings highlight a need to consider medical cannabis as a possible alternative to prescribing opioids for older adults—a sentiment expressed publicly at a recent Senate Special Committee on Aging hearing entitled, “Opioid Use Among Seniors – Issues and Emerging Trends.” At the state level, Montana and New Mexico recently have moved to approve cannabis for dying patients. In doing so, these states have established a viable alternative to address the long-standing public health failure to adequately treat pain at the end of life (Imhof & Kaskie, 2008). Not only have these state policy makers facilitated targeted access to those who would appear to benefit substantially from taking medical cannabis, they have taken a substantial leap to advance implementation of the federal Patient Self-Determination Act of 1989. In particular, by adding end of life to the roster of qualified conditions, these states have facilitated the opportunity for older adults to participate in directing their own course of end-of-life care and have offered a greater number of real choices about dying as pain-free as possible.

Conclusion We have used an age–period–cohort paradigm to explicate divergent pathways of cannabis use among the older adult population and demonstrate how attitudes, laws, and individual health needs can shape these paths. This analysis has lead us to identify several kinds of research that would be useful to policy makers. On the one hand, we certainly recognize a need for more biomedical studies focusing on the individual health outcomes of taking cannabis for a wide array of age-related diseases and disorders. We also see a need for clinical research studies that compare older adults’ use of cannabis with prescription opioids and other pharmaceutical derivatives such as cannabidiol (Ahmed et al., 2015). On the other hand, there is a need to expand public health research that encompasses the legal, medical, and behavioral issues surrounding cannabis use and older adults. How are doctors and other professionals talking to older patients about medical cannabis? Should states with limited MMLs extend coverage to more age-related medical conditions such as end of life? Should states extend insurance coverage for older adults who take cannabis as a substitute for opioids? At this time, these sorts of critical public health policy questions cannot be answered largely because there is a pervasive lack of reliable and representative information being collected about cannabis and older persons. A statewide or national survey that accounts for how changing legal, medical, and other norms have affected older adults’ attitudes and behaviors about taking cannabis certainly would help advance the public policy conversation.

Meanwhile, the United States is about to enter a period when the older adult population is expected to double (Ortman et al., 2014), the cannabis economy may grow fivefold (Caulkins et al., 2015), and federal officials continue to wrestle incrementally with a variety of controversial and technical issues such as whether cannabis should be classified in the same category as heroin (Bostwick, 2012). Although these certainly are critical issues for federal policy makers to resolve, it is here we turn our attention to the critical role of the states. For more than two decades, cannabis policy across the United States has reflected a model of federalism in which state governments have become laboratories, as demonstrated by the increasing number of states that have advanced medical cannabis programs, the lack of enforcement being exercised by key federal agencies, and the recent decision by the Supreme Court to refuse to consider the state of Nebraska’s claim against the state of Colorado (Sevigny & Pacula, 2014). By not actively enforcing the supremacy of federal policy concerning the classification of cannabis as a Schedule 1 narcotic, the states have been left to experiment with some of the most critical aspects of program development and implementation such as establishing eligibility criteria, defining dispensation mechanisms, financing, and maintaining oversight (Sevigny & Pacula, 2014). Perhaps these laboratories also will experiment with increasing use of cannabis among older persons as a way to reduce opioid misuse or the undertreatment of pain at the end of life.

Funding This research was supported by the Department of Health Management and Policy, University of Iowa.

Acknowledgments The authors thank Brad Wright for reviewing this manuscript.

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