The timing of follow-up visits was anchored to the date of the participant’s baseline assessment . “Pre-pandemic” observations were any assessment occurring between study entry and March 19, 2020, the date of the first state-issued stay-at-home order, so each youth could contribute multiple assessments. Among youth contributing pre-pandemic data to analyses , there were an average of 3.0 pre-pandemic assessments . During the COVID-19 pandemic, participants were invited to complete three web-based surveys in June 2020 , December 2020 , and June 2021 . Of the 348 participants included in analyses, 237 completed the June 2020 survey, 213 completed the December 2020 survey, and 195 completed the June 2021 survey. Completers of the prepandemic and during-pandemic assessments were sociodemographically similar . Among the youth contributing during pandemic data to analyses , there were an average of 2.2 during-pandemic observations. Altogether, 60 youth contributed only pre-pandemic data, 67 youth contributed only during pandemic data, and 221 youth contributed both pre- and during pandemic data. Analyses were conducted in R v4.1.2 . We estimated the impact of the COVID-19 pandemic by comparing observations of same-age youth assessed at four different time points: prepandemic , June 2020, December 2020, and June 2021. Conceptually, we used the prepandemic data to construct a reference curve for the expected drinking or nicotine use as a function of age, then compared that reference curve to the observed drinking and nicotine use as a function of age at each survey wave during the pandemic. In this way, we sought to distinguish the effects of the pandemic from age-related changes in drinking or nicotine use that would have occurred even outside the pandemic context. We restricted the sample to participants ≤ age 15.8 years at study entry to reduce potential cohort effects on drinking and nicotine use introduced by study entry criteria or by secular changes in drinking or nicotine use among U.S. young adults between 2016 and 2021 . If cohort effects were present, they would be confounded with the effect of the COVID-19 pandemic .

Preliminary analyses showed date of birth was not predictive of drinking or nicotine use in the restricted sample after controlling for age,vertical farming equipment suppliers suggesting any remaining cohort effects were minimal . In addition, we restricted observations to those of participants ages 18.8–22.4 years old at each time point, to ensure we had observations covering the same age span at each of the four assessment time points and avoid extrapolation beyond the common region of support . Outcomes included the proportion of young adults drinking or using nicotine, the number of days drinking or using nicotine among those reporting any use, and the typical number of drinks per drinking day . Regressions were fit in the geepack package , clustering observations on participant, specifying an exchangeable correlation structure, and using robust standard errors. For dichotomous dependent variables, a logistic link function was used. Model specification included fixed effects for sex, race, ethnicity, study site, age at observation, age-at-observation-squared, and time point of assessment. Participant sex, race, ethnicity, and study site were included as covariates given previous work has established they predict alcohol and nicotine use . Age at observation was included to implement our age-based identification strategy ; both linear and quadratic effects were included to account for nonlinear developmental changes in alcohol and nicotine use across this age range . Time point of assessment was a four-level categorical variable , represented by dummy variables with prepandemic as the reference level. Follow-up models investigated whether the effect of the COVID-19 pandemic varied as a function the impact of the pandemic on participants’ financial security. We expanded the primary model described above by adding the main effect of financial impact and terms capturing the interaction of financial impact with time point. We then tested the statistical significance of the interaction via a Wald test .

Regression models compared drinking and nicotine use at the three during-pandemic time points to drinking and nicotine use pre-pandemic. Fig. 1, Panel A graphs the model-estimated means for a 20-year-old participant across time points, which are interpreted next. Compared to pre-pandemic , significantly fewer participants reported any past-month drinking in June 2020 and December 2020 , with the difference no longer being statistically significant in June 2021 . Compared to pre-pandemic, those reporting any past-month drinking drank on 1.83 more days in June 2020 , with the difference no longer being statistically significant in December 2020 or June 2021 . Compared to pre-pandemic, there were no significant differences at any of the three during-pandemic time points in the number of drinks on a typical drinking day or the binge drinking or nicotine use outcomes . Tables 2 and 3 reports the corresponding effect sizes. Compared to pre-pandemic, 4–5% fewer participants engaged in past month binge drinking in June 2020 and December 2020, though neither difference was statistically significant . We did not find evidence that the degree to which the pandemic impacted participants’ financial security moderated the pandemic’s impact on drinking outcomes . We found evidence that the degree to which the pandemic impacted participants’ financial security moderated the pandemic’s impact on the number of days using nicotine among past-month users but not the prevalence of past-month nicotine use . Fig. 1, Panel B graphs the interactions for the nicotine use outcomes. Among those reporting any past-month nicotine use, participants who experienced moderate-to-extreme financial impact increased the number of days using nicotine while those with no financial impact decreased the number of days using nicotine in June 2020 . We investigated changes in drinking and nicotine use from prepandemic baseline over the first 15 months of the COVID-19 pandemic in a sample of 348 emerging adults ages 18–22 years old. Compared to pre-pandemic, in June 2020, fewer young adults reported past-month drinking, but those who did were drinking on more days. Compared to pre-pandemic, in December 2020, fewer young adults reported past-month drinking, but those who did were no longer drinking on significantly more days. By follow-up in June 2021, on average, there were no significant differences from pre-pandemic patterns of alcohol and nicotine use.

Findings are consistent with previous short-term studies showing a pandemic related increase in the number of days drinking. In our data, this change reflected a different distribution of drinking across the population: compared to pre-pandemic, fewer young adults were drinking, but those who did drank more frequently. While two previous studies found decreases in binge drinking , we did not find a statistically significant change in the number of days of binge drinking at any time point in the current study. However, the non-significant reduction we observed in binge drinking in June and December 2020 was directionally consistent with these previous studies. In addition, the time frame of measurement may explain the discrepancy: those two previous studies focused on changes earlier during the pandemic, in March and April 2020, whereas another study focusing on changes in June and July 2020 also found no significant change in binge drinking. As in one previous study , we did not find an average effect of the pandemic on nicotine use. However, this appeared to obscure opposing changes among those who suffered vs. did not experience impacts on their financial security. Relative to pre-pandemic, in June 2020, those with past-month nicotine use had increased the number of days using if they experienced financial impact and had stable or decreased number of days using if they denied experiencing financial impact . Loss of job or reduction in work hours could increase smoking during periods of boredom at home or to cope with the attendant stress . This pattern is consistent with the larger literature documenting how the pandemic may exacerbate health disparities based on pre-existing socioeconomic advantage . However, moderation of multiple outcomes was tested, so the current findings should be regarded as preliminary and await replication. This study had limitations. First,grow lights shelves findings may not generalize beyond emerging adults ages 18–22 years old . Second, for nicotine use, we did not measure the quantity used each day, which could have changed. Third, we did not consider other substances such as cannabis. Fourth, the mode of assessment differed from the prepandemic to during-pandemic assessments, potentially introducing differences.Fifth, secular changes in the rates of alcohol or nicotine use among young adults between 2016 and 2021 could be confounding the effect of the pandemic, potentially introducing bias.Sixth, pre-pandemic responses on a free-response scale had to be mapped onto the discrete response options , potentially limiting precision. Seventh, we assessed the degree to which the pandemic impacted individuals’ financial security but not the form of this impact . Eighth, pre-pandemic observations were not anchored to the months of June and December, so seasonal effects could explain part of the observed differences. We reported here the most extended follow-up to date of pandemic related changes in drinking and nicotine use in emerging adults. The study had several further strengths. We used seven years of prepandemic assessments and a rigorous age-based design to identify the pandemic’s impact over and above typical developmental changes. We incorporated three assessments spanning the first 15 months of the pandemic to study whether early changes in drinking and nicotine use persisted. Participants spanned five sites across the U.S and multiple racial and ethnic backgrounds. Finally, we focused on a critical developmental period associated with elevated risk for problematic use . In summary, in a heterogeneous group of young adults, pandemic related changes in drinking patterns were no longer detectable in June 2021. Pandemic-related increases in nicotine use occurred only for participants who reported greater impact of the pandemic on their financial security—these subgroup effects were no longer statistically significant in June 2021, though a large effect size for past-month nicotine use remained. Thus, those whose financial security has been adversely impacted by the pandemic may reflect a vulnerable group worth targeting for supports to manage drinking and nicotine use.

Continued follow-up beyond summer 2021 is necessary to verify that the pandemic’s effects on drinking and nicotine use have indeed faded and understand the pandemic’s long-run impacts of substance use trajectories into adulthood. Parkinson’s Disease treatment has been based on dopamine replacement therapy for 35 years. Yet, side effects resulting from long-term use of DA agonists, namely dyskinesias and on–off responses, are prompting investigations of alternative neurotransmitter manipulations to modulate basal ganglia function and normalize motor activity. Dyskinesias often result from lesion or disturbance affecting the transcortical loop or indirect pathway, with disruption of balance between excitation and inhibition in the globus pallidus pars externa-subthalamic nucleus-globus pallidus pars interna circuit. Thus, dyskinesias reflect altered patterns of neuronal firing in this circuit, which result in the improper selection of specific motor programs and, eventually, in the development of hyperkinetic movements . Endocannabinoids, the endogenous ligands of cannabinoid receptors, are synthesized upon demand by neurons in response to depolarization , and, once released, diffuse backwards across synapses to suppress pre-synaptic GABA or glutamate release . Because of these properties, the endocannabinoid system may offer new pharmacological targets for the treatment of neurologic conditions characterized by abnormal firing patterns. One application of cannabinoidbased therapeutics would be for dyskinetic syndromes, hyperkinetic disorders characterized by changes in pattern, synchronization, mean discharge rates, and somatosensory responsiveness of neurons in the direct and indirect extrapyramidal motor circuits . Further applications of cannabinoid-based therapeutics may extend to treatment of seizure disorders, changes in behavioral or cognitive state resulting from hypersynchronous excessive neuronal discharges in other, for example, limbic, cortical or thalamic circuits. To test the hypothesis that endocannabinoids act as endogenous antidyskinetic agents with modulatory effects on abnormal basal ganglia circuits, we examined endocannabinoid production in specific areas of the basal ganglia of rats infected with Borna disease virus and how cannabinoid agonists and antagonists affect their motor behaviors. Borna disease virus is a negative strand RNA virus epidemiologically linked to patients with neuropsychiatric disorders and Parkinson’s-plus syndromes . After infection, BD rats develop an extrapyramidal disorder with spontaneous dyskinesias, hyperactivity, stereotypic behaviors, partial DA deafferentation, DA agonist hypersensitivity, and Huntington’s-type striatal neuropathology . Our investigations revealed elevations in the endocannabinoid anandamide in the subthalamic nucleus of BD rats, associated with increased metabolic activity in this key basal ganglia relay nucleus.