Pen needles are an important component of insulin delivery among insulin-requiring patients with diabetes. Despite this, only 35.6% of patients in our sample reportedly had any kind of reimbursement for their PNs (exact coverage could not be verified). This has important implications around patients’ overall care, outcomes and costs. We found that patients who lack PN reimbursement may have significant unmet needs (compared to those who have their PNs reimbursed). These patients had a higher prevalence of lipohypertrophy and increased hospitalizations, insulin use, and overall costs. Although these associations do not indicate causality, they nonetheless indicate that these patients represent a population where improvements in treatment are needed to improve their outcomes and decrease overall costs.
We observed that patients without PN reimbursement had greater costs compared to those with PN reimbursement, even after controlling for various clinical and demographic characteristics. A large portion of these increased costs is likely attributable to hospitalizations, as significant differences in hospitalization rates were observed in bivariate analyses and hospital costs are greater in scale compared to other costs (i.e., insulin costs). Although not directly attributable to PN reimbursement in this study, increased diabetes-related hospitalization and costs nonetheless indicate that these patients experience greater complications that require more intensive medical care.
Patients without PN reimbursement also had increased insulin costs, as a function of greater insulin utilization. The difference in daily average insulin costs (1.45 RMB per day) amounts to approximately 529 RMB per year. Despite their greater utilization of insulin, patients without PN reimbursement had similar average HbA1c levels as those with PN reimbursement, implying that these patients required more insulin to control their blood glucose. The clinical significance of this association is unclear. One reason why this was observed may be due to an increased observed prevalence of lipohypertrophy among these patients.
Despite most patients in the study reporting they had received injection instruction at some point in their lives, only 16.8% received instruction in the year prior. Proper site rotation, as defined by this study to be both site rotation and moving the injection point at least 1 cm away from the prior injection point, was poor overall. However, upon sub-analysis, we found that while patients with PN reimbursement did not move the injection point at least 1 cm away from the prior injection point significantly more often, they did rotate sites significantly more often which was associated with a lower prevalence of lipohypertrophy. The difference in site rotation practices amongst the reimbursed population may allude to a variance in the type of instruction received those reimbursed for PNs. Patients who did rotate generally may have had the intention of proper site rotation, but lack of education on injection technique, or retention, could have undermined their efforts. This finding emphasizes the need for more frequent education on proper injection technique. We also found that more patients without PN reimbursement reused their PNs, and did so more frequently compared to those that had PN reimbursement. PNs are intended for single-use only, yet many patients—especially those without PN reimbursement—reused their PNs. Reuse of PNs has been shown in previous studies to be associated with the development of lipohypertrophy [12, 13]. In particular, one study in Spain among 430 outpatients injecting insulin found that needle reuse greater than 5 times was strongly associated with greater lipohypertrophy [12.]. Another cross-sectional study by Ji et al., conducted in 2010 among 380 diabetes patients across 20 centers in mainland China, also found a significant positive relationship between the frequency of single needle reuse and lipohypertrophy [13]. In the Ji study, the mean number of uses per needle was 9.2, with approximately 26.8% of patients using the PN 10 or more times. Among patients who reused their needles, the most frequent reasons for reusing were for convenience and to save money.
With a growing prevalence of diabetes and use of insulin therapy [1, 14], the lack of reimbursement for PNs may have costly implications. Efforts to improve the quality of care for these patients should be multifaceted, incorporating increased and more frequent patient education, improvements in treatment and monitoring, and implementation of measures to improve patients’ use of prescribed treatment modalities such as PNs.
Evidence suggests that patients’ OOP costs may play a significant role in treatment adherence and clinical outcomes, leading to further potential medical and economic implications.[15] As saving money has been cited as a frequent reason for reusing needles,[13] reimbursement of PNs can help to reduce the overall cost burden on the patient, thereby reducing needle reuse. This may in turn help to reduce lipohypertrophy, which is associated with needle reuse. The healthcare system in China has historically adopted a principle of “broad coverage, with low basic level of benefits”—that is, providing coverage for the greatest number of people with the trade-off of limited levels of benefits. Despite the importance of PNs as a component of diabetes therapy, coverage of PNs has largely been overlooked. Though a larger emphasis is usually placed on drugs rather than medical devices, PNs (or syringes) represent a necessary component for all patients to reliably and safely inject their insulin.
This study has several limitations. First, it is cross-sectional in which we measure both exposures and outcomes at a single point in time. Therefore, although we can observe associations in patient characteristics and outcomes, we cannot evaluate temporal relationships or establish causality on these relationships. Future work should be performed to conduct longitudinal analyses of these outcomes to better understand these relationships over time.
Patients’ healthcare utilization (i.e., outpatient clinic visits and hospitalization) was solicited in the survey via self-report over a recall period of 6 months; this longer period of time may introduce recall bias, in which patients may have difficulty remembering their healthcare utilization during this period, thus resulting in potentially inaccurate estimates of outpatient clinic visits and/or hospitalization. This may be a concern more for minor types of healthcare utilization (e.g., outpatient clinic visits) rather than major events such as hospitalizations. In tradeoff, a shorter time period would increase the risk of not being representative of patients’ healthcare resource utilization.
Total healthcare costs (as opposed to resource utilization) associated with inpatient stays, outpatient visits and insulin use were also not directly solicited from the patient. Therefore, we had to rely on published or private estimates of these costs from the literature or other sources of data. Actual costs may vary widely, especially since different levels of resource intensity may be used depending on the reason for the outpatient visit or hospital stay. Subsequent research should be performed to measure actual healthcare utilization and costs for these patients to shed further insight on the economic burden of these patients.
Many factors can impact patients’ quality of care and outcomes. Disease- and treatment-related factors such as comorbidities, severity of disease, local treatment practices, reimbursement policies for other diabetes-related treatments, and medication adherence can impact patients’ outcomes. We were unable to completely control for these factors, though we were able to control for certain patient comorbidities (such as cardiovascular disease and hyperlipidemia) and complications of diabetes (such as retinopathy, nephropathy, neuropathy, or other complications) as a proxy for severity of disease.
Finally, the studied patient population represents those from endocrinology clinics within four large tertiary hospitals in China, and thus may not be representative of the entire insulin-prescribed diabetes population in China. Larger studies across multiple, geographically-representative centers are needed to better understand the impact of PN reimbursement on health outcomes and costs nationally.
With the limitations being said, this research provides empirical data regarding healthcare costs burden for diabetic patients without PN reimbursement in China. To our best knowledge, this is the first study that explores the differences in economic burden between patients who receive some degree of reimbursement for PNs and those who have to pay 100% out-of-pocket for PNs in China. The work addresses a binary question of whether having some extent of PN reimbursement helps alleviate the economic burden for patients who rely on PN-delivered insulin injections to manage their diabetes. Future research is needed to further evaluate how the degree of reimbursement (i.e., percent of costs reimbursed) may affect the healthcare costs for this patient population, especially those with low income.