Department of Health Policy and Organization, School of Public Health, The University of Alabama at Birmingham.
Center for Outcomes and Effectiveness Research and Education, Heersink School of Medicine, The University of Alabama at Birmingham.
JAMA Netw Open. 2024 Aug 1;7(8):e2425280. doi: 10.1001/jamanetworkopen.2024.25280.
Many insulin users ration doses due to high out-of-pocket costs. Starting January 2020 with Colorado, 25 states and the District of Columbia enacted laws that cap insulin copayments.
To estimate the association of Colorado's $100 copayment cap with out-of-pocket spending, medication adherence, and health care services utilization for diabetes-related complications.
DESIGN, SETTING, AND PARTICIPANTS: In this cohort study using Colorado's All-Payer Claims Database, nonelderly insulin users with type 1 diabetes were analyzed from January 2019 to December 2020. Outcome changes were compared in the prepolicy and postpolicy period among individuals continuously enrolled in state-regulated and non-state-regulated plans using difference-in-differences regressions. Subgroup analyses were conducted based on individuals' prepolicy spending (low: never ≥$100 out-of-pocket vs high: ≥$100 out-of-pocket cost at least once). Data were analyzed from June 2023 to May 2024.
Enrollment in state-regulated health insurance plans subject to the copayment cap legislation.
Adherence to basal and bolus insulin treatment was evaluated using the proportion of days covered measure, out-of-pocket spending reflected prescription cost for a 30-day supply, and health care utilization for diabetes-related complications was identified using primary diagnosis codes from medical claims data.
The panel included 1629 individuals with type 1 diabetes (39 096 person-months), of which 924 were male (56.7%), 540 (33.1%) had 1 or more comorbidities, and the mean (SD) age was 40.6 (15.9) years. Overall, the copayment cap was associated with out-of-pocket spending declines of $17.3 (95% CI, -$27.3 to -$7.3) for basal and $11.5 (95% CI, -$24.7 to $1.7) for bolus insulins and increases in adherence of 3.2 (95% CI, 0.0 to 6.5) percentage points for basal and 3.3 (95% CI, 0.3 to 6.4) percentage points for bolus insulins. Changes in adherence were associated with increases within the prepolicy high-spending group (basal, 9.9; 95% CI, 2.4 to 17.4 percentage points; bolus, 13.0; 95% CI, 5.1 to 20.9 percentage points). The policy was also associated with a mean reduction of -0.09 (95% CI, -0.16 to -0.02) medical claims for diabetes-related complications per person per month among high spenders, a 30% decrease.
In this cohort study of Colorado's insulin copayment cap among individuals with type 1 diabetes, the policy was associated with an overall decline in out-of-pocket spending, an increase in medication adherence, and a decline in claims for diabetes-related complications only among insulin users who spent more than $100 in the prepolicy period at least once.
重要性：由于自付费用高昂，许多胰岛素使用者会定量配药。自 2020 年 1 月科罗拉多州开始，有 25 个州和哥伦比亚特区颁布了胰岛素共同支付额上限的法律。
目的：评估科罗拉多州 100 美元共同支付额上限与自付支出、药物依从性以及与糖尿病相关并发症相关的医疗保健服务使用之间的关联。
设计、地点和参与者：在这项使用科罗拉多州全支付者索赔数据库的队列研究中，分析了 2019 年 1 月至 2020 年 12 月间患有 1 型糖尿病的非老年胰岛素使用者。通过差异差分回归，在州监管和非州监管计划中连续参保的个体中，比较政策前和政策后时期的结果变化。根据个体的政策前支出（低：从未自付超过 100 美元与高：至少一次自付超过 100 美元）进行亚组分析。数据于 2023 年 6 月至 2024 年 5 月进行分析。
暴露：参与受共同支付额上限立法约束的州监管健康保险计划。
主要结果和措施：使用覆盖天数比例衡量基准和餐时胰岛素治疗的依从性，通过 30 天处方成本反映自付支出，通过医疗索赔数据中的主要诊断代码确定与糖尿病相关并发症的医疗保健利用情况。
结果：该研究纳入了 1629 名患有 1 型糖尿病的个体（39096 人月），其中 924 名男性（56.7%），540 名（33.1%）患有 1 种或多种合并症，平均（SD）年龄为 40.6（15.9）岁。总体而言，共同支付额上限与基础胰岛素自付支出减少 17.3 美元（95%CI，-27.3 至 -7.3）和餐时胰岛素自付支出减少 11.5 美元（95%CI，-24.7 至 1.7）相关，基础胰岛素和餐时胰岛素的依从性分别提高了 3.2 个百分点（95%CI，0.0 至 6.5）和 3.3 个百分点（95%CI，0.3 至 6.4）。依从性的变化与政策前高支出组的增加有关（基础胰岛素，9.9；95%CI，2.4 至 17.4 个百分点；餐时胰岛素，13.0；95%CI，5.1 至 20.9 个百分点）。该政策还与高支出者每月每人医疗索赔中与糖尿病相关并发症相关的平均减少 -0.09（95%CI，-0.16 至 -0.02）相关，减少了 30%。
结论和相关性：在这项针对科罗拉多州 1 型糖尿病患者胰岛素共同支付额上限的队列研究中，该政策与自付支出总体下降、药物依从性提高以及与糖尿病相关并发症相关的索赔减少相关，但仅在政策前至少一次自付超过 100 美元的胰岛素使用者中观察到这一结果。
