The association between marijuana use and mental health also seems to vary by gender, although the evidence is inconsistent. We do however know that women move from initiation of cannabis use to problematic use much faster than men do. This is referred to as a telescoping effect . This may suggest differences in both reasons for use and patterns of use . In addition to rapid progression to problematic use, it appears as though marijuana has a stronger mental health impact for women than men . Women, but not men, previously diagnosed with depressive disorders and who use marijuana regularly had poorer SF-12 mental health scores compared to women who did not use marijuana . And, in a study by Lev-Ran looking at the association between mental health and quality of life in the general population, those who used marijuana had poorer mental health than those who did not, and reported experiencing lower levels of vitality and accomplishing less due to emotional problems. These differences were greater among women than men . These findings highlight the importance of considering gender in the study of motives of marijuana use and mental health, as motives might provide additional insight into what drives gender differences in the association between marijuana use and mental health outcomes. Frequency of use. Heavy marijuana use, operationalized as near daily use, has been demonstrated to be detrimental to the transition to adulthood as it has been associated with poorer educational and occupational outcomes . Compared to young adults who do not use marijuana or to those who use infrequently, heavy users are the least likely to have transitioned to an adult role by the age of 28 . Frequency of use also seems to play a role in the relationship between marijuana use in adolescence and adverse young adult outcomes,vertical growing system including depression and anxiety . However, Green and Ritter found no association between frequency of marijuana use and depression in young adult men.
Furthermore, data from the Australian National Survey of Mental Health and Well-Being indicates a positive association between marijuana use and the occurrence of affective disorders, in addition to the fact that those who used marijuana more often reported greater levels of psychological distress, greater limitations in their everyday lives due to emotional distress, and lower life satisfaction . LevRan et al. reported that for those with anxiety disorders, regular, weekly use of marijuana was associated with a decrease in mental health quality of life compared to participants who did not use. This association was not present for participants who reported less than weekly use . Daily use of marijuana in young adult women has been associated with a fivefold increase in the odds of depression and anxiety . Here too, findings highlight the importance of considering frequency of use in the study of marijuana use and mental health outcomes, as frequency of use seem to influence the relationship between marijuana use and mental health outcomes. Given that an association between marijuana use and depressive symptoms, and marijuana use and anxiety symptoms have at times been demonstrated, it is crucial to understand under which circumstances such associations are present. Motives of marijuana use may be key to do so. Better understanding the nature of these associations is especially significant for young adults given their mental health vulnerability, the rising rates of affective disorders and of marijuana use, and that individuals suffering from comorbid substance use and symptoms of depression and anxiety have a worsened clinical course and outcomes and are at higher risk of suicide, impairments, and disability . Alcohol Motives. As previously mentioned, foundational work on motives of use comes from the alcohol literature. Thus, the four most common motives discussed in the literature are borrowed from the alcohol literature. These are social motives, conformity motives, coping motives, and enhancement motives. Social motives are defined as externally generated positive reinforcement motives to obtain positive social rewards . An example of a social motive is celebration. Conformity motives are also externally generated negative reinforcement motives to avoid social censure or rejection .
An individual’s use will be driven by a conformity motive either to fit in with a group or due to peer pressure because everyone else is using. Coping motives are conceptualized as internally generated negative reinforcement motives to reduce or regulate negative emotions . As an example, an individual’s use will be driven by a coping motive if he uses because he has had a bad day, or is frustrated. Enhancement motives are internally generated positive reinforcement motives to enhance positive mood or well being . Examples of enhancement motives are enjoyment and altered perceptions. In work done by Cooper, there was a positive, significant association between enhancement, coping and social motives with quantity and frequency of drinking . There was a negative, significant association between conformity motives and quantity of drinking . Furthermore, coping, enhancement, and conformity motives were predictors of drinking problems, but social motives were not . It is likely that social motives were not predictors of drinking problems as for this given motive, drinking is occasional and only occurs in social, celebratory situations. Marijuana Motives. Although there is an overlap in motives of alcohol and marijuana use, some motives are specific to marijuana use . For the purposes of this dissertation, marijuana motives of use are: 1) motives that promote positive experiences, which are motives of celebration, altered perceptions, experimentation, enjoyment, alcohol, relative low risk, and availability; 2) motives for avoidance of negative experiences, which are motives of coping, conformity, sleep, boredom; and social anxiety; and 3) medical motives, which are motives of attention, substitution, natural remedy, pain, and nausea. Figure 2.2 details the reasons for use an individual might endorse for each of these motives. Previous research has demonstrated that motives of use are associated with differing patterns of use and risk for marijuana use problems .
Differential associations between motives of use and problematic use outcomes have been consistently documented . With regards to problematic use outcomes, enhancement, expansion, coping and social motives of marijuana use have been uniquely associated with greater frequency of marijuana use in the past 30 days . When examining whether there were differences between severity of use and motives endorsed, BonnMiller & Zvolensky demonstrated that individuals with marijuana dependence endorsed motives of expansion and enhancement more frequently than those who used marijuana only occasionally or regularly. Individuals with cannabis dependence endorsed more social motives than those who used occasionally, those who used regularly, and those who abused marijuana. Individuals with dependence to marijuana also endorsed more conformity motives than those who abused marijuana. With regards to coping motives, those with dependence endorsed more coping motives than those suffering from abuse or reporting regular, occasional use. These findings demonstrate that those with marijuana dependence are more likely to use marijuana to adjust their affective states and rely on marijuana to cope with life stressors. However, with regards to mental health as an outcome, the differential association between motives of use with both diagnoses and symptoms of depression and anxiety as outcomes has yielded inconsistent findings. For a given motive and associated outcome, findings have differed across studies. One consistency however,plant growing rack is the association of coping related motives of use with poor or worse outcomes. For instance, Green & Ritter found that individuals between the ages of 30 and 40 who endorsed coping related motives reported more symptoms of depression than those who endorsed non-coping related motives of use. With regards to anxiety symptoms, Bonn-Miller, Zvolensky & Bernstein found that anxiety sensitivity was incrementally associated with coping and conformity motives, whereas enhancement was negatively associated with it. However, Moitra, Christopher & Stein found that only coping motives, and not conformity motives, were significantly associated with negative affect. When considered as a moderator, only those who reported using to cope showed poorer mental health, increased symptoms of psychopathology, more psychosocial distress, and more life events than those who did not use . Focusing on symptoms of depression and symptoms of anxiety, which are precursors to diagnoses is not trivial. Subclinical symptoms of depression and anxiety have been associated with an increased likelihood of full blown disorders in adulthood . Most of the research reviewed has focused on clinically diagnosed depression and anxiety. It is not clear however, if these findings generalize to less severe symptoms. The generalizability is important because clinical disorders may be contraindicated with marijuana use, whereas less several symptoms may not. Gender. Gender differences have also been observed in the association between motives of marijuana use and mental health outcomes. These differences may be due to differences in motives of use endorsed as well as ensuing patterns of use. With regards to gender, expectancies for marijuana use mediated the association between coping motivated use and anxiety in women, but not men . In work done by Buckner, Zvolensky & Schmidt social anxiety was associated with marijuana related problems, coping, and conformity motives.
In women, social anxiety was related to social motives but not marijuana use related problems . However, existing work has seldom considered potential gender differences in endorsed motives for use and in the association between motives of use and symptoms of depression, symptoms of anxiety, and overall psychological distress. For this dissertation, gender is included as a moderator in Cooper’s Motivational Model of Alcohol Use as motives of use endorsed, patterns of use, and ensuing outcomes are likely to differ by gender. Thus, it is important to understand the role of gender in the association between motives of use and mental health to develop successful, gender specific prevention and intervention programs, should need be. Although work has been done to understand marijuana motives of use and associated outcomes, there are some gaps particularly relevant to a context with legal access to marijuana, that this dissertation seeks to address. There is however much that remains to be understood about the associations between motives of marijuana use and mental health outcomes in young adults who use marijuana, particularly in a context of facilitated access to marijuana. First, samples used in research thus far have mostly been identified as individuals who use marijuana for medical reasons only or as individuals who use marijuana for recreational reasons only, thus reporting an illegal behavior in this latter group. Until now, work has yet to be done that considers motives of marijuana use and associated mental health outcomes in a sample of young adults comprised of individuals who use marijuana exclusively for medical reasons, exclusively for recreational reasons or for both medical and recreational reasons, in a context with a longstanding history of legalized medical marijuana. Second, current instruments used to operationalize motives of marijuana use have been validated using college samples which are not representative of the marijuana using population at large. Furthermore, these instruments do not include motives specific to medical marijuana use when it has been demonstrated that medical and recreational marijuana use overlap significantly . There is a need for an instrument that operationalizes marijuana motives of use, to include both recreational as well as medical motives of use given the significant overlap in use . Furthermore, this instrument needs to be validated in a diverse sample of young adults who use marijuana for recreational and/or medical reasons. The sample to be used in this dissertation addresses this shortcoming. Third, in the limited literature that presents research done on motives of marijuana use and mental health outcomes, the focus is often on diagnoses of depression and/or anxiety. A better understanding of the association between motives of use and symptoms of depression and motives of use and symptoms of anxiety is a primordial precursor not only to detangling the association between marijuana use and diagnoses of depression and anxiety, but also, because symptoms are an avenue ripe for intervention. This is particularly salient for young adults as we want to be able to intervene early, should need be, to maximize the likelihood of a successful transition into adulthood. Fourth, even less is known about potential gender differences in the association between motives of marijuana use and symptoms of depression, symptoms of anxiety, and overall psychological distress.