The significant increase in the complexity of diabetes care over the last two decades is associated with a high economic burden (1), with almost one-quarter of adults with diabetes burdened with significant out of pocket expenses (OOPEs) (2). Little is known about the OOPEs for families of adolescents and young adults with type 1 diabetes. We therefore report the diabetes-related OOPEs for these families from the SEARCH for Diabetes in Youth (SEARCH) study and their association with demographic, socioeconomic, clinical, and health care characteristics.
A detailed description of the SEARCH study methods has previously been published (3). Participants had a baseline visit shortly after diabetes diagnosis and one or more follow-up visits; this report includes data from a follow-up visit between November 2011 and July 2015, at which time participants’ diabetes duration was >5 years. Participants ≥18 years old or a parent/guardian of participants <18 years old completed surveys, including questions about sociodemographics, diabetes treatment, health insurance, and OOPEs. The primary outcome was OOPEs in a typical month. Monthly OOPEs were captured in intervals of unequal lengths expressed in 2013 U.S. dollars as $0, $1–19, $20–49, $50–99, $100–199, and ≥$200.
Descriptive analyses were based on the midpoint of each interval. The midpoint of the last interval (≥$200) was estimated at $278, based on MarketScan data (4). Interval-censored regression models were fit assuming a Weibull distribution to evaluate the association between categories of OOPEs and covariates. The relationship between OOPEs and each covariate was assessed after adjustment for nonmodifiable characteristics (model 1), modifiable clinical factors (model 2), and health insurance categories (model 3). SAS 9.4 was used for analyses. An a priori α = 0.05 was used to assess statistical significance.
After exclusion of 221 participants with missing OOPEs data from the 2,384 participants with type 1 diabetes who completed a follow-up visit, 2,163 participants were included in these analyses. At the visit, mean ± SD age was 17.0 ± 4.7 years and mean diabetes duration was 7.9 ± 1.9 years. The median monthly diabetes-related OOPE was estimated at $64.60. Approximately 60% of participants had OOPEs of at least $50 per month, and 40% at least $100 per month.
Table 1 shows the adjusted association of OOPEs presented as an OOPE rate relative to the reference group and 95% CIs. Participants whose parents had not completed high school had lower OOPEs compared with participants whose parents had at least a high school education (model 3: OOPE rate 0.55 [95% CI 0.34, 0.88]). OOPEs were lower for families with household income of <$25,000 compared with families with household income of $50,000–74,000 (model 3: OOPE rate 0.66 [95% CI 0.49, 0.88]). OOPEs were higher for families who received diabetes care from an adult endocrinologist or family practitioner versus a pediatric endocrinologist (model 3: OOPE rate 1.47 [95% CI 1.14, 1.9] and 1.69 [95% CI 1.07, 2.67], respectively). Insulin injections were associated with lower OOPEs than insulin pumps (model 3: OOPE rate 0.82 [95% CI 0.69, 0.98] for regimens including long-acting insulin and 0.72 [95% CI 0.52, 0.98] for regimens not including long-acting insulin). Continuous glucose monitoring (CGM) use was associated with higher OOPEs (model 3: OOPE rate 1.35 [95% CI 1.08, 0.1.68]). OOPEs were lower in those who had public health insurance (OOPE rate 0.22 [95% CI 0.18, 0.27]) compared with those with private health insurance.
This study is subject to limitations. The survey was cross-sectional, and data on OOPEs and treatment measures were obtained from self-reported surveys. The data were obtained between 2011 and 2015 and might not account for higher insulin costs and newer diabetes technologies that evolved since then (5). Additionally, the OOPEs reported are only related to diabetes medications and supplies and do not account for copays or coinsurance for clinic or hospital visits and insurance premiums. We also do not report on other expenses that might be incurred, such as productivity losses due to missed work or school. Lastly, our descriptive analyses were based on the midpoint of each cost interval. Since the intervals are not equal, this could misestimate the variation in the amount paid between individuals. The midpoint for the highest interval was derived from empirical data (4) and may underestimate OOPEs given the long tail of high expenditures.
Our findings suggest that most adolescents and young adults with type 1 diabetes have some OOPEs related to diabetes medications and supplies. These OOPEs vary with different demographic and clinical factors. Future studies may explore causal pathways that drive higher OOPEs and whether OOPEs create barriers and disparities in health care utilization. This will ultimately help develop interventions to improve access to health care for underserved populations.
SEARCH is indebted to the many youth and their families, and their health care providers, whose participation made this study possible. This study includes data provided by the Ohio Department of Health, a fact that should not be considered an endorsement of this study or its conclusions.
Funding. SEARCH 3 is funded by the Centers for Disease Control and Prevention (PA numbers 00097, DP-05-069, and DP-10-001) and supported by the National Institute of Diabetes and Digestive and Kidney Diseases. SEARCH 4 (1UC4DK108173) is funded by the National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health (NIH), and supported by the Centers for Disease Control and Prevention. The Population Based Registry of Diabetes in Youth Study (1U18DP006131, U18DP006133, U18DP006134, U18DP006136, U18DP006138, and U18DP006139) is funded by the Centers for Disease Control and Prevention and supported by the National Institute of Diabetes and Digestive and Kidney Diseases, NIH. Sites and grant numbers (SEARCH 3 and 4) are as follows: Kaiser Permanente Southern California (U18DP006133, U48/CCU919219, U01 DP000246, and U18DP002714), University of Colorado Denver (U18DP006139, U48/CCU819241-3, U01 DP000247, and U18DP000247-06A1), Cincinnati Children's Hospital Medical Center (U18DP006134, U48/CCU519239, U01 DP000248, and 1U18DP002709), University of North Carolina at Chapel Hill (U18DP006138, U48/CCU419249, U01 DP000254, and U18DP002708), Seattle Children's Hospital (U18DP006136, U58/CCU019235-4, U01 DP000244, and U18DP002710-01), and Wake Forest University School of Medicine (U18DP006131, U48/CCU919219, U01 DP000250, and 200-2010-35171). For SEARCH 3 and 4, the authors acknowledge the involvement of the Kaiser Permanente Southern California Clinical Research Center (funded by Kaiser Foundation Health Plan and supported in part by the Southern California Permanente Medical Group); the South Carolina Clinical & Translational Research Institute at the Medical University of South Carolina, NIH/National Center for Advancing Translational Sciences (NCATS) grants UL1 TR000062 and UL1 TR001450; Seattle Children's Hospital and the University of Washington, NIH/NCATS grant UL1 TR00423; University of Colorado School of Medicine Pediatric Clinical Translational Research Center, NIH/NCATS grant UL1 TR000154; the Barbara Davis Center at the University of Colorado Denver, Diabetes Endocrinology Research Center NIH grant P30 DK57516; the University of Cincinnati, NIH/NCATS grants UL1 TR000077 and UL1 TR001425; and the Children with Medical Handicaps program managed by the Ohio Department of Health.
The findings and conclusions in this report are those of the authors and do not necessarily represent the official position of the Centers for Disease Control and Prevention or the National Institute of Diabetes and Digestive and Kidney Diseases.
Duality of Interest. No potential conflicts of interest relevant to this article were reported.
Author Contributions. L.M., C.P., and D.R.W. wrote the manuscript, researched data, contributed to the discussion, and reviewed the manuscript. Statistical analyses were performed by J.D. and N.F. All authors reviewed and contributed to the final manuscript. L.M. is the guarantor of this work and, as such, had full access to all the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.
Prior Presentation. Parts of this study were presented in abstract form at the 76th Scientific Sessions of the American Diabetes Association, New Orleans, LA, 10–14 June 2016.