Patients with deductible plans that do not include SUD as a covered benefit are responsible for bearing the cost of those services until their deductible is reached, and/or the accumulating cost of copays for multiple visits as part of the SUD care model. We did not include type of insurance as a covariate due to its collinearity with deductible limits and enrollment via the ACA exchange . We categorized deductible limits into three levels , as in prior research and based on the definition of high deductibles and benefit plans available at KPNC during this period. Since deductible limits may change over time, we used the minimum level over each 6- month time window during follow-up. We imputed missing deductible levels during a given 6-month window with the last known value during the follow-up period, and we dropped patients with no known deductible limit during the entire 36 months of follow-up from the analysis . Coverage mechanism included enrollment via the California Exchange vs. other mechanisms . We summarized utilization data into 6-month intervals, and we examined trends in health service utilization over 36 months after patients received an SUD diagnosis with Chi-squared tests using 6-month intervals. Using multi-variable logistic regression, we examined associations between deductible limits, enrollment via the California ACA Exchange, membership duration, and psychiatric comorbidity; and the likelihood of utilizing health services in the 36-month follow-up period, controlling for patient demographic characteristics and chronic medical comorbidity. We also evaluated whether enrollment via the California ACA exchange moderated the associations between deductible limits and the likelihood of utilization by adding interaction terms to the multi-variable models. We estimated the associations with deductible limits for each enrollment mechanism by constructing hypothesis tests and confidence intervals on linear combinations of the regression coefficients from these models.
To account for correlation between repeated measures,ebb and flow we used the generalized estimating equations methodology . We censored patients at a given 6-month interval if they were not a member of KPNC during that time. We conducted a sensitivity analysis to determine whether high utilizers leaving the health system influenced the observed pattern of decreased utilization from the 0–6 month to the 6–12 month follow-up periods. Using Chi-squared tests, we compared utilization during the 0–6 month period between patients who remained in the cohort and patients who disenrolled from KPNC at 6–12 months. We hypothesized that if the censored group had greater utilization than the non-censored group, then there would be evidence of high utilizers leaving the health system. We also conducted Chi-squared tests to determine whether censorship was associated with deductible limits and enrollment mechanisms. This study examined longitudinal patterns of healthcare utilization among SUD patients and their relationships to key aspects of ACA benefit plans, including enrollment mechanisms and deductible levels. We anticipated that the increase in coverage opportunities that the ACA provided would bring high-utilizing patients into health systems, driving up overall use of healthcare. Consistent with prior studies of SUD treatment samples that have found elevated levels of healthcare utilization either immediately before or after starting SUD treatment , results of our longitudinal analysis showed that utilization among people with SUDs was highest immediately after initial SUD diagnosis at KPNC, and declined to a stable level in subsequent years. This suggests that the initial high utilization may be temporary.This overall trend in utilization is a welcome finding, and consistent with the intent of the ACA to increase access to care; however, the subsequent decrease in utilization could also signify that patients are disengaging from treatment.
Although we cannot specifically attribute the initial levels of utilization to lack of prior insurance coverage, as we did not have data on prior coverage, we found that individuals with fewer than 6 months of membership before receiving an SUD diagnosis were more likely to utilize primary care and specialty SUD treatment than those who had 6–12 months of membership. This suggests that future healthcare reforms that expand insurance coverage for people with SUDs might also lead to short-term increases in utilization for a range of health services. Deductibles are a key area of health policy interest given the growing number of people enrolling in deductible plans post-ACA. As anticipated, higher deductibles had a generally negative association with utilizing healthcare in this population. We found that patients with high deductibles had lower odds of using primary care, psychiatry, inpatient, and ED services than those without deductibles. Additionally, we found the associations between high deductibles and likelihood of utilizing primary care and psychiatry were strongly negative among ACA Exchange enrollees. Although it is somewhat difficult to gauge the clinical significance of these specific results, the strength of the odds ratios for primary care and psychiatry access gives some indication of the potential impact. The associations of high deductibles with primary care and psychiatry access is worrying given the extent of medical and psychiatric comorbidities among people with SUDs . Although we found more consistent associations for higher deductibles and less healthcare initiation, it is possible that even a modest deductible could deter patients from seeking treatment . From a public policy and health system perspective, the possibility that deductibles could prevent people with SUDs from accessing any needed medical care is a cause for concern. Consistent with prior findings , our results suggest that high deductibles have the potential to dissuade SUD patients from accessing needed health services, and that those who enroll via the ACA exchange may be more sensitive to them. This could be attributable to greater awareness of coverage terms due to the mandate that exchange websites offer clear, plain-language explanations to compare insurance options .
In contrast, high deductibles were associated with a greater relative likelihood of SUD treatment utilization. However, this association existed only among patients who enrolled via mechanisms other than the ACA Exchange. It is possible that individuals with emerging or unrecognized substance use problems may have selected higher deductible plans at enrollment due to either not anticipating use of SUD treatment, which is often more price-sensitive relative to other medical care , or not being aware of the implications of deductibles. However, once engaged in treatment, individuals with high deductibles may have been motivated to remain there. A contributing factor could also be that such patients were required to remain in treatment either by employer or court mandates, which are common and are associated with retention . The varying associations between deductibles and different types of health service utilization by enrollment mechanisms highlight the need for future research in this area. Insurance exchanges provide access to tax credits, a broader range of coverage levels, and information to assist in healthcare planning that might be less easily accessible through other sources of coverage, e.g., through employers . In our sample, Exchange enrollment was associated with greater likelihood of remaining a member of KPNC, did not demonstrate an adverse association with routine care,dry racks and was associated with lower ED use. However, primary care and psychiatric services use were similar across enrollment types, even within low and high deductible limits. Prior studies have found that health plans offered through the ACA Exchange are more likely to have narrow behavioral health networks compared to other non-Exchange plans and primary care networks , which raises concerns about treatment access. For this health system, that concern appears unfounded. Psychiatric comorbidity was associated with greater service use of all types. Several prior studies have also found that patients with psychiatric comorbidity use more health services than those with SUD alone . Similar to our results, a recent study based in California found that after controlling for patient-level characteristics, the strongest predictors of frequent ED use post-ACA included having a diagnosis of a psychiatric disorder or an SUD . While the ACA was not expected to alter this general pattern, the inclusion of mental health treatment as an essential benefit was intended to improve availability of care and to contribute to efforts to reduce unnecessary service utilization. Our investigation confirms the ongoing importance post-ACA of psychiatric comorbidity and suggests that future efforts in behavioral health reform must anticipate high demand for healthcare in this vulnerable clinical population. It is also worth noting that nonwhite patients were less likely to initiate SUD and psychiatry treatment. Race/ethnic disparities in access to care are a longstanding concern in the addiction field . Some expected these disparities to be mitigated postACA . Findings on race/ethnic differences are similar to what has been observed in other health systems ; although, few studies have examined associations post-ACA. One prior study among young adults with SUD and psychiatric conditions post-ACA found modest ethnic disparities in lack of coverage between whites and other ethnic groups ; although, another study of young people more broadly found larger gains in coverage among Hispanics and Blacks relative to whites . The race/ethnic disparities in SUD and psychiatry treatment initiation in this cohort, in which overall insurance coverage was not a barrier but specific mechanisms could be, highlight the importance of addressing this complicated challenge to health equity.
E-cigarette use, or vaping, among adolescents has become a public health concern, with 26.7% of high school seniors reporting past-month vaping in 2018, and 900,000 middle and high school students reporting daily or near-daily use. Adolescents’ use of e-cigarettes is associated with an increased risk of subsequent cigarette initiation and frequent use, an increased risk of nicotine dependence, and exposure to potentially toxic chemicals. Despite harm reduction claims by e-cigarette companies, in cross-sectional studies, e-cigarette use among adolescent and young adult dual users is associated with smoking a greater number of cigarettes per day , more frequent smoking, and fewer attempts to quit smoking. Notably little is known about the stability of adolescents’ use of e-cigarettes over time, such as whether non-daily use progresses into daily use and whether daily use is sustained. The potential for harm from exposure to nicotine and toxicants is likely to be greater with sustained and frequent use over time. Study of longitudinal patterns of adolescent e-cigarette use is needed to model the potential for harm from these products. Furthermore, research is needed to articulate adolescent patterns of dual product use over time and the resulting levels of nicotine and toxicant exposure. It remains unclear, for example, whether dual users succeed in reducing and stopping their cigarette use or whether they continue to dual use over time. The stability in adolescents’ e-cigarette preferred type or brand also has not been examined. E-cigarette brands that are popular today among adolescents can deliver nicotine from a single compact pod that equals that of a pack of cigarettes, in attractive flavors, and with easy concealment for use in settings where cigarettes may be forbidden . These characteristics may facilitate the progression from intermittent to frequent use and nicotine dependence. Alternatively, low nicotine content and/or low device appeal may result in adolescents losing interest in e-cigarettes over time, with diminishing frequency and dependence risk. Among adults, research indicates that evolving from a simpler e-cigarette device to a more complex modifiable device is a common pattern and is associated with greater dependence on e-cigarettes. Despite rapid growth in the e-cigarette market in recent years, research has not yet examined whether or how adolescents’ preferred devices change over time, particularly with regard to nicotine delivery and exposure. Finally, minimal research has examined changes in adolescents’ reasons for initiating, continuing, and/or quitting e-cigarette use over time. In cross-sectional survey studies, adolescents’ top reasons for experimenting with e-cigarettes include curiosity, appealing flavors, friends’ use, and perceived benefits compared with cigarettes. However, reasons may shift over time, as adolescents move from experimentation to sustained use. The literature on youth initiation and transition to regular use of combustible cigarettes shows that media/marketing and social influences motivate initiation, whereas the drive for nicotine due to addiction motivates regular use. These nicotine product use patterns observed with combustible cigarettes warrant investigation with e-cigarettes. With e-cigarettes, adolescents who begin experimenting because of curiosity or appealing flavors may subsequently use to alleviate withdrawal symptoms.