The highly infectious nature of the COVID-19 virus, its rapid spread throughout the world, and the significant mortality associated with it have greatly changed many peoples’ lives . Often, individuals are encouraged to limit transmission by restricting time out of the home to necessary activities, such as obtaining food or medical care, working, and exercise, depending on the locality . This policy of limiting contact with others is often termed “social distancing” , though some prefer “physical distancing” to encourage ongoing social interaction . Evidence from across the population in China, which was first impacted by COVID-19, suggests that levels of anxiety, depressive, and post-traumatic stress symptoms were higher than expected after the outbreak of COVID-19, with poorer sleep quality as well . Also, this evidence suggests that young adults, 21–30 years, may be most affected . Xiong et al. reviewed the literature on mental health symptoms from eight countries after the COVID-19 outbreak and found high rates of anxiety, depressive, and post-traumatic stress symptoms, with elevations in stress and psychological distress as well; those 40 years and younger and who were students were more affected than older age groups and non-students . Evidence also suggests that substance use has increased, with the best evidence for increased alcohol use , though increases are not always found and vary around the strictness and timing of COVID-related lockdowns . These inconsistencies may also result from the population studied and levels of preexisting use, with greater increases in alcohol use among adults with higher pre-existing levels of alcohol use . Cannabis use changes related to COVID-19 are virtually unstudied, with only one study finding decreased use prevalence but increased use frequency among Canadian adolescents .
The effects of COVID-19 are largely unstudied in college students, but they are already a group at elevated risk for substance use and mental health symptoms , Young adults, 18–25 years of age, have the highest marijuana grow system, illicit drug, and prescription drug misuse rates of any cohort, with alcohol use prevalence rates that only slightly trail those of adults aged 26–39 years . Among young adults, college students have higher rates of problematic alcohol use than non-college students , with increasing rates of cannabis use and alcohol-cannabis co-use . The typical college years coincide with the peak age period for incidence of many mental health conditions , with high rates of depressive disorders, anxiety disorders , and poor sleep . Significant substance use and mental health symptoms are each linked to poorer academic performance, college dropout, and other poor outcomes , yet the vast majority of affected students do not receive treatment, likely due to inadequate campus resources . College students have experienced many significant COVID-related stressors, including the transition to distance learning, unstable housing situations and/or unexpected moves back to the parental home, cancelled or delayed graduation ceremonies, and disrupted access to campus-based mental health treatment . Self-report of changes in mental health symptoms suggest increases in stress and mood disorder symptoms , but these are limited by smaller samples.On the one hand, two studies suggested increases in alcohol use , while three studies found decreases in alcohol use following university closures . A sixth found a complex pattern of changes, with increases in frequency of use that were counteracted by declines in quantity of use and binge drinking, all of which was moderated by pre-COVID use patterns . While college students are an important population in which to examine changes in mental health and substance use related to COVID- 19, the findings are limited by conflicting data on alcohol use changes. Also, studies to date have not assessed cannabis use in U.S. college students. Given this limited evidence on college student mental health and substance use related to university closures, outstanding questions remain about cannabis use changes and the degree of change and direction of mental health and alcohol use changes. To address these outstanding questions, we used data from the U.S. college-based Stimulant Norms and Prevalence study. This cross-sectional study collected data from college students on mental health symptoms, alcohol, and cannabis use from September 2019 to May 2020, allowing for examination of differences in psychopathology symptoms from before to after outbreaks of COVID-19 in the students’ communities. Our primary aim was to examine differences related to university COVID-19 closure announcements in mental health and substance use in U.S. college students. To evaluate differences in average symptom levels before and after COVID-19 closure announcements , zero-inflated negative binomial regression was used for count outcomes . Thus, the main independent variable in all analyses was pre- or post-CCA survey completion status.
Substance use outcomes are likely to be characterized by long-term abstinence in some participants, while other participants are not abstinent. The ZINB models account for both kinds of substance patterns simultaneously via a 2-part model, with a binary part of the model seeking to identify complete abstinence , and a second count part of the model accounting forsubstance use rates via negative binomial regression. This approach to modeling accounts for dual processes that can occur during substance use, where some participants might have zero use during a period of time but still potentially engage in use at other times , while some participants might never engage in any substance use . Of note, the binary part of the model addressing binge drinking prevented model convergence, likely as a consequence of limited variance explained. Linear regression was used for continuous outcomes.In addition to hypothesis tests, we evaluated effect sizes in terms of incidence risk ratios for the count process part of ZINB models testing for days of use, odds ratios for the binomial process part of ZINB models testing for any 30-day use, and raw unit differences in LR . To further support model choice, we ran overdispersion tests following approaches suggested by Venables and Ripley and we tested for zero-inflation and improvements in model fit compared to simpler models using Vuong non-nested model tests . Both overdispersion and zero-inflation were consistently detected across models. We also evaluated moderation by SES, sex at birth, and race/ ethnicity through statistical interactions with the COVID cancellation announcement . Moderators were dummy coded with reference groups of “poor” for SES, “male” for sex, and “White, non-Hispanic/ Latino” for race/ethnicity. Per Benjamini and Hochberg , all moderator hypothesis tests were adjusted using false discovery rate procedures , such that each single predictor/outcome was considered as a separate family of hypotheses for evaluation . To account for site-based clustering of participants, university/site served as a fixed effects covariate . Missing data were very limited except for binge drinking . To address missing data, multiple imputation was employed using predictive mean matching and the fully conditional specification . All analyzed variables were included in the imputation model, and 40 imputations were employed . The R statistical software language version 4.0.2 was used for all analyses, including the “mice” package for multiple imputation and the “pscl” package for ZINB regression . These results provided evidence of generally greater levels of substance use and psychopathology in students completing the survey after their university’s COVID closure announcement , though changes were generally modest and not seen for all outcomes. On the one hand, depressive symptoms and anger were greater in students who completed the survey after their CCA, though anxiety symptoms did not vary.
In the model with all participants, sleep interference was non-significant, though in the model without participants whose data straddled their university’s CCA, post-CCA participants had significantly greater sleep interference. This was a very small effect, though. Furthermore, most alcohol and cannabis vertical farming use indicators were higher in those taking the survey post-CCA, yet binge drinking days were lower in those assessed after closings. None of the pre-to post-CCA differences in substance use or mental health symptoms were moderated by sex at birth, race/ ethnicity, or SES. Together, these findings suggest a picture of modestly higher levels of substance use, depressive symptoms, and anger among U.S. college students from pre-through a two-month period post-university closure. These results, however, do not correspond with research in other countries about COVID-related mental health among young adults and students. That research suggested much larger differences in mental health symptoms than found here . One reason could be that our methodology compared two separate groups of college students, while the predominant measure in other studies has been for the participant to self-report change in symptoms after the spread of COVID-19 in their community, which is likely to suffer from retrospective bias. Alternatively, U.S. college students may perceive lesser threat from COVID-19 than non-U.S. samples. For alcohol use, our results add to the conflicting literature in U.S. college students by suggesting increases in frequency of use and level of consequences but decreases in binge use. Our findings are most similar to those of Jackson et al. , as they found increases in frequency but decreases in indices of heavy use. Clinically, these results suggest that universities and care providers for college students need to carefully screen for alcohol and cannabis use and for depressive symptoms and problematic anger in students. Sleep problems also may warrant examination. While the overall level of pre-to post-CCA difference in outcomes was modest, that does not mean that a specific individual’s change related to university closings will necessarily be modest. Data from across Australian adults found the greatest increases in alcohol use among those with greater pre-COVID levels of use , and providers should be aware of the possibility for greater increases among those with pre-existing substance use and mental health problems. Furthermore, these data only examine the first two months post-CCA, and substance use and mental health symptoms are likely to continue changing in college students. Ensuring continuity of care to those already enrolled in treatment could be crucial in preventing significant problems in the most vulnerable students. In addition, universities may need to increase availability of substance use and mental health treatment services, but given that most college students who need treatment do not receive it while in college , college health professionals may need to consider innovative screening, outreach, and broad use of self-help materials and/or technology-aided treatment solutions to reach a broad and dispersed population of students . First, participants are younger, four-year undergraduate students at public universities and are not a representative sample of all college students.
These include older students, private school students, and those attending two-year schools. Second, these results cannot be generalized to non-college young adults, who differ in significant ways from young adults in college. Another limitation comes from the measures employed: while they have strong psychometrics, they also were brief screening measures, and post-traumatic stress symptoms were not assessed. Also, the measures captured retrospective ratings of 30-day substance use and 14-day mental health symptoms. As such, students who completed the survey within 30 or 14 days of their university’s CCA were reporting on both pre- and post-CCA experiences for substance use and/or psychopathology symptoms, respectively. Those who were in the pre-CCA sample were reporting on only pre-CCA dates. This means that the post-CCA ratings should be interpreted in light of the inclusion of limited pre-CCA data. With that said, we performed sensitivity analyses that suggested only one change in significance when participants were excluded if they had data including both pre- and post-CCA days. Furthermore, these data are cross-sectional, which prevents tests of within-participant change and reduces the strength causal inference in the relationships of COVID-19/CCAs and mental health or substance use changes. Finally, the data are subject to both self-report and selfselection bias, given the nature of the data and that some eligible students opted to participate in other research studies for course credit. These weaknesses, however, were balanced by the large and diverse sample from seven universities/colleges across the U.S. the valid and reliable measures of alcohol use, cannabis use, and psychopathology, and the robust analytic plan.In a broad sample of U.S. college students, days of alcohol and cannabis use, prevalence of alcohol use and alcohol use consequences, depressive symptoms, and anger were all significantly higher in participants who provided data in the two months post-university closing, versus pre-closing.