Economic impact of compliance to treatment with antidiabetes medication in type 2 diabetes mellitus: a review paper

Abstract

Objectives: Suboptimal compliance and failure to persist with antidiabetes therapies are of potential economic significance. The present research aims to describe the impact of poor compliance and persistence with antidiabetes medications on the cost of healthcare or its components for patients with type 2 diabetes mellitus (T2DM).

Methods: Literature search was conducted in PubMed for relevant articles published in the period between 1 January 2000 and 30 April 2009. Thus, it is possible that relevant articles not listed in PubMed, but available in other databases are not included in the current review. Studies describing economic consequence of compliance and/or persistence with pharmaceutical antidiabetes treatment were identified. The variability in the studies reviewed was high, making it extremely difficult to make a comparison between them.

Results: Of 449 articles corresponding to the primary search algorithm, 12 studies (all conducted in USA) fulfilled the inclusion criteria regarding the economic impact of compliance and/or persistence with treatment on the overall cost of T2DM care or its components. Compliance was assessed via medication possession ratio (MPR) in ten studies, where it ranged from 0.52 to 0.93 depending on regimen. Persistence was assessed in one study. Mean total annual costs per T2DM patient varied between the studies, ranging from $4570 to $17338. In seven studies, medication compliance was inversely associated with total healthcare costs, while in four other studies inverse associations between medication compliance and hospitalisation costs were reported. In one study increased adherence did not change overall healthcare costs.

Conclusions: Improved compliance may lead to reductions of the total healthcare costs in T2DM, Further research is needed in countries other than the US to assess impact of compliance and persistence to pharmacotherapy on T2DM costs in country-specific settings.     

Resource utilisation and costs in patients with type 2 diabetes mellitus treated with insulin glargine or conventional basal insulin under real-world conditions in Germany: LIVE-SPP study

Objective: To assess and compare the total costs relevant to diabetes care in patients with type 2 diabetes mellitus (T2D) treated at specialised diabetes practices with either insulin glargine- or conventional basal insulin (neutral protamine Hagedorn [NPH])-based therapies from the German statutory health insurance (SHI) perspective.

Methods: The Long Acting Insulin Glargine Versus NPH Cost Evaluation in Specialised Practices (LIVE-SPP) study is an observational, retrolective, multicentre longitudinal cost comparison in adults with T2D. Costs were evaluated from the German SHI perspective based on official 2005 prices. Average total costs per patient for insulin glargine-versus NPH-based therapies were compared using multivariate general linear modelling. Sensitivity analyses were performed by varying the main cost factors by ± 25%.

Results: Patients (n=1,024, 512 patients per cohort) were on average 62 years of age, with an average 8-year diabetes history at study start. The average unadjusted total annual costs per patient were €1,868.41 (95% CI 1,744.27–1,992.56) for insulin glargine-based vs. €2,063.72 (95% CI 1,922.91–2,204.54) for NPH-based therapies. Average adjusted total annual costs per patient between insulin glargine- (€1,241.13) and NPH-based therapies (€1,607.86) were statistically significantly different (p=0.0004). The economic advantage for insulin glargine-based therapies resulted mainly from fewer blood glucose measurements and other diabetes-related materials (e.g. needles). The savings remained stable in one-way sensitivity analyses.

Conclusions: The LIVE-SPP study suggests that insulin glargine-based therapies may offer an economic advantage over NPH-based therapies.     

Insulin degludec versus insulin glargine U100 for patients with type 1 or type 2 diabetes in the US: a budget impact analysis with rebate tables

Background and aims: Drug rebates are almost universally negotiated privately between the manufacturer and the payer in the US. The aim of the present study was to illustrate the use of a “rebate table” to improve the transparency and utility of published budget impact analyses in the US by modeling ranges of hypothetical rebates for two comparators. Worked examples were conducted to illustrate the budgetary implications of using insulin degludec (IDeg) relative to insulin glargine (IGlar) U100 in patients with type 1 or 2 diabetes.

Methods: A short-term (1-year) budget impact model was developed to evaluate the costs of switching to IDeg from IGlar in patients with type 1 or 2 diabetes on basal-bolus and basal-only insulin, respectively. The analysis used insulin dose and hypoglycemia data from recent randomized trials, data on the prevalence of diabetes, and estimates of the proportion of patients using each insulin regimen. The model was configured to run multiple rebate scenarios to generate a rebate table in a hypothetical 1 million member commercial plan.

Results: Relative to IGlar, IDeg resulted in reductions in non-severe and severe hypoglycemia incidence and costs both in patients with type 1 and patients with type 2 diabetes. Insulin acquisition costs were higher, and respective rebates of 7.3% and 10.6% were required for IDeg to break-even with IGlar at the full list price. Incremental per member per month IDeg costs without a rebate were USD 0.04 in type 1 diabetes and USD 0.80 in type 2 diabetes.

Conclusions: Using IDeg instead of IGlar at list price could result in a modest increase in costs when considering insulin and hypoglycemia costs alone, but modest incremental rebates with IDeg would result in cost neutrality relative to IGlar. In addition, IDeg would result in reduced incidence of severe and non-severe hypoglycemia.     

Comparison of treatment costs in inadequately controlled type 2 diabetes in Germany based on the APOLLO trial with insulin glargine

Abstract

Objective: A cost analysis of once-daily insulin glargine versus three-times daily insulin lispro in combination with oral antidiabetic drugs (OADs) for insulin-naive type 2 diabetes patients in Germany based on the APOLLO trial (A Parallel design comparing an Oral antidiabetic drug combination therapy with either Lantus once daily or Lispro at mealtime in type 2 diabetes patients failing Oral treatment).

Methods: Annual direct treatment costs were estimated from the perspective of the German statutory health insurance (SHI). Costs accounted for included insulin medication, disposable pens and consumable items (needles, blood glucose test strips and lancets). Sensitivity analyses (on resource use and unit costs) were performed to reflect current German practice.

Results: Average treatment costs per patient per year in the base case were €1,073 for glargine and €1,794 for lispro. Insulin costs represented 65% vs. 37% of total costs respectively. Acquisition costs of glargine were offset by the lower costs of consumable items (€380 vs. €1,139). Sensitivity analyses confirmed the robustness of the results in favour of glargine. All scenarios yielded cost savings in total treatment costs ranging from €84 to €727.

Conclusions: Combination therapy of once-daily insulin glargine versus three-times daily insulin lispro both with OADs, in the management of insulin-dependent type 2 diabetes offers the potential for substantial cost savings from the German SHI perspective.     

Cost-effectiveness analysis of dapagliflozin treatment versus metformin treatment in Chinese population with type 2 diabetes

Background and objective: Dapagliflozin is the first SGLT2 inhibitor available in China, where the disease burden of diabetes and its complications is very heavy. Because a new diabetes treatment strategy for diabetes should consider its cost-effectiveness, compared with an existing treatment, this study aimed to examine the cost-effectiveness between dapagliflozin and metformin treatment in China.

Methods: The Cardiff Diabetes Model (CDM) was used to estimate cost effectiveness and macro- and micro-vascular outcomes of dapagliflozin vs metformin. The CDM effectiveness inputs were derived from indirect comparative efficacy data from meta-analysis of 71 studies comparing monotherapy and add-on therapy of dapagliflozin vs metformin: dapagliflozin or metformin monotherapy, add-on therapy with other oral hypoglycemic agents, and add-on therapy with insulin. Direct medication costs and medical costs on treating diabetes were calculated based on published and local sources. A discount rate of 3% was applied to both costs and health effects. Univariate and probabilistic sensitivity analyses (PSA) were performed to assess uncertainties.

Results: The total healthcare costs accumulated over the lifetime on dapagliflozin treatment arm was 8,626 Chinese yuan higher than the metformin treatment arm for an individual patient, and the quality adjusted life years (QALYs) gained with dapagliflozin treatment was 0.8 more than metformin treatment. Therefore, an incremental cost-effectiveness ratio was 10,729 yuan per QALY gained for dapagliflozin treatment arm vs metformin treatment arm. The cost-effectiveness results were robust to various sensitivity analyses.

Conclusion: Dapagliflozin treatment was more cost-effective compared with metformin treatment for Chinese type 2 diabetes patients. However, the findings of favorable cost-effectiveness results for dapagliflozin are largely driven by the effects of favorable weight profile on clinical, utility, and costs in the Cardiff model.     

Economic simulation of canagliflozin and sitagliptin treatment outcomes in patients with type 2 diabetes mellitus with inadequate glycemic control

Abstract

Objectives:

This study examines the association between changes in diabetes-related quality measures (QMs) (HbA1c, systolic and diastolic blood pressure [BP], low-density lipoprotein cholesterol [LDL-C], and body weight) and healthcare costs in Type 2 diabetes mellitus (T2DM) patients. It also performs an economic simulation that evaluates the cost implications of the changes in QMs and of the incidence rates (IRs) of adverse events (AEs) associated with canagliflozin (CANA) and sitagliptin (SITA) treatments in a real-world setting.

Methods:

Health-insurance claims and electronic medical records from the Reliant Medical Group database (2007–2011) were used to identify adult patients with T2DM receiving metformin and sulfonylurea who did not achieve adequate glycemic control. The association between the changes in QMs and healthcare costs was evaluated using multivariate regression and non-parametric bootstrap methods. AE-related costs were taken from the literature. The cost impact of CANA and SITA outcomes was evaluated using the aforementioned costs and the changes in QMs and the IRs of AEs observed in a recent phase 3 trial comparing CANA and SITA as third oral agent (DIA3015).

Results:

Eight hundred and fifty-six T2DM patients were identified (mean age?=?65.8; female 45.4%). The regression analysis found that increases of 1 percentage point in HbA1C and 1% in systolic and diastolic BP, LDL-C, or weight were associated with a per patient per year (PPPY) cost increase of $4476 (p?=?0.028) and $566 (p?=?0.006), a decrease of $362 (p?=?0.070) and $7 (p?=?0.817), and an increase of $241 (p?=?0.481), respectively. The economic simulation showed that changes in QMs and IRs of AEs equivalent to those reported in DIA3015 would be associated with a reduction in PPPY healthcare costs of $6061 (p?=?0.036) for CANA and $2190 (p?=?0.098) for SITA.

Conclusions:

This study suggests that integrated approaches that manage to control a combination of quality measures are most successful at reducing downstream healthcare costs.     

Economic modelling of costs associated with outcomes reported for type 2 diabetes mellitus (T2DM) patients in the CANVAS and EMPA-REG cardiovascular outcomes trials

Aims: To model direct medical costs associated with reductions in cardiovascular disease (CVD) events in T2DM patients reported in the CANVAS and EMPA-REG trials, which assessed the cardiovascular safety of canagliflozin and empagliflozin, respectively.

Materials and methods: Costs were modeled from a US managed care organization (MCO) perspective for the CVD outcomes included in both trials: three-point major adverse cardiovascular event (MACE) and its components (cardiovascular-related death, nonfatal myocardial infarction, nonfatal stroke), as well as heart failure requiring hospitalization. The rate of CVD events averted (difference between study drug and placebo) was projected to the portion of an MCO T2DM population matching the respective trial’s inclusion criteria. A targeted literature search for paid amounts directly associated with each CVD event provided the unit costs, which were applied to the projected number of events averted, to calculate costs avoided per member per year (PMPY). One-way sensitivity analyses were performed on events averted, unit costs, and percentages of trial-applicable patients.

Results: Based on three-point MACE events averted, costs avoided PMPY of $6.17 (range: $1.27–$10.94) for CANVAS and $2.75 ($0.19–$4.83) for EMPA-REG were estimated. Costs avoided for individual components of MACE ranged from $0.77 to $3.84 PMPY for CANVAS and from -$0.97 (additional costs) to $1.54 for EMPA-REG. PMPY costs avoided for heart failure were $2.72 for CANVAS and $1.32 for EMPA-REG.

Limitations and conclusions: Models assumed independent, non-recurrent outcomes and were restricted to medical costs directly associated with the trial-reported events. The reductions in CVD events in T2DM patients reported for both CANVAS and EMPA-REG project to a positive cost avoidance for these events in an MCO population. The analysis did not include an assessment of the impact on total cost, as the costs associated with adverse events, drug utilization or other clinical outcomes were not examined.     

Economic outcomes of exenatide vs liraglutide in type 2 diabetes patients in the United States: results from a retrospective claims database analysis

Abstract

Objective:

The safety and efficacy of the GLP-1 receptor agonists exenatide BID (exenatide) and liraglutide for treating type 2 diabetes mellitus (T2DM) have been established in clinical trials. Effective treatments may lower overall treatment costs. This study examined cost offsets and medication adherence for exenatide vs liraglutide in a large, managed care population in the US.

Methods:

This was a retrospective cohort analysis comprising adult patients with T2DM who initiated exenatide or liraglutide between 1/1/2010 and 6/30/2010 and had 6 months pre-index and post-index continuous eligibility. Patients were propensity score-matched to controls for baseline differences. Medication adherence was measured by proportion of days covered (PDC). Paired t-test and McNemar’s test were used to compare outcomes.

Results:

Matched exenatide and liraglutide cohorts (n?=?1347 pairs) had similar average total 6-month follow-up costs ($6688 vs $7346). However, exenatide patients had significantly lower mean pharmacy costs ($2925 vs $3272, p?<?0.001). Among liraglutide patients, patients receiving the 1.8?mg dose had significantly higher average total costs compared to those receiving the 1.2?mg dose ($8031 vs $6536, p?=?0.026), with higher mean pharmacy costs in the 1.8?mg cohort ($3935 vs $3146, p?<?0.001). There were no significant differences in inpatient or outpatient costs or medication adherence between groups (mean PDC: exenatide 56% vs liraglutide 57%, p?=?0.088).

Limitations:

The study assumed that all information needed for case classification and matching of cohorts was present and not differential across cohorts. The study did not control for covariates that were unavailable, such as HbA1c and duration of diabetes.

Conclusions:

Patients initiating exenatide vs liraglutide for T2DM had similar medication adherence and total healthcare costs; however, exenatide patients had significantly lower total pharmacy costs. Patients prescribed 1.8?mg liraglutide had significantly higher costs compared to those on 1.2?mg.     

Real-world comparison of hospitalization costs for heart failure in type 2 diabetes mellitus patients with established cardiovascular disease treated with canagliflozin versus other antihyperglycemic agents

Abstract

Aims: This real-world study compared hospitalization for heart failure (HHF) costs and all-cause healthcare costs in patients with type 2 diabetes mellitus (T2DM) and established cardiovascular disease treated with the sodium glucose co-transporter 2 inhibitor (SGLT2i) canagliflozin and non-SGLT2i antihyperglycemic agents (AHAs).

Materials and methods: Propensity score-matched cohorts from a retrospective observational study (OBSERVE-4D) using the Truven MarketScan Commercial Claims and Encounters and Optum Clinformatics databases were analyzed. HHF and all-cause healthcare costs per-patient-per-month (PPPM) were compared for patients initiated on canagliflozin and non-SGLT2i AHAs in the on-treatment analysis.

Results: Baseline characteristics were well balanced between matched cohorts that included new users of canagliflozin or non-SGLT2i AHAs in the Truven (13,954 and 45,101, respectively) and Optum (11,490 and 53,360, respectively) databases. The mean (95% CI) PPPM cost of HHF was lower for canagliflozin than for non-SGLT2i AHAs in analyses of both the Truven ($21.31 [$21.25, $21.37]) and Optum ($30.43 [$30.41, $30.45]) databases. The mean (95% CI) PPPM all-cause healthcare cost was also lower for canagliflozin than for non-SGLT2i AHAs in analyses of both the Truven ($321 [$280, $361]) and Optum ($449 [$402, $495]) databases.

Limitations: This study is subject to the limitations inherent to observational research including potential for coding errors and biases and unobserved confounding. Because all patients were in commercially administered health plans, these findings cannot be easily generalized to uninsured or Medicaid populations. Patient costs were evaluated up to and including their first HHF event. Post-discharge costs such as the costs of subsequent rehospitalizations were not included in this analysis.

Conclusions: For patients with T2DM and established cardiovascular disease in this real-world study, treatment with canagliflozin was associated with lower HHF costs and all-cause healthcare costs compared with treatment with non-SGLT2i AHAs.     

Economic impact of severe and non-severe hypoglycemia in patients with Type 1 and Type 2 diabetes in the United States

Abstract

Objective:

To identify the direct and indirect costs of hypoglycemia in patients with Type 1 or Type 2 diabetes mellitus (DM) in the US setting.     

Cost-effectiveness of insulin detemir compared with neutral protamine Hagedorn insulin in patients with type 1 diabetes using a basal-bolus regimen in five European countries

Abstract

Objectives: The aim of this analysis was to evaluate the long-term clinical and economic outcomes associated with insulin detemir and neutral protamine Hagedorn (NPH) insulin in combination with mealtime insulin aspart in patients with type 1 diabetes in Belgian, French, German, Italian and Spanish settings.

Methods: The published and validated IMS CORE Diabetes Model was used to make long-term projections of life expectancy, quality-adjusted life expectancy and direct medical costs. The analysis was based on patient characteristics and treatment effects from a 2-year randomised controlled trial. Events were projected for a time horizon of 50 years. Potential uncertainty using a modelling approach was addressed.

Results: Basal-bolus therapy with insulin detemir was projected to improve quality-adjusted life expectancy by 0.45 years versus NPH in the German setting, with similar improvements in the other countries. Insulin detemir was associated with cost savings in Belgium, Germany and Spain. In France and Italy, lifetime costs were slightly higher in the detemir arm, leading to incremental cost-effectiveness ratios of €519 per QALY gained and €3,256 per QALY gained, respectively.

Conclusions: Compared to NPH, insulin detemir is likely to be a dominant treatment strategy in Belgium, Germany and Spain and highly cost-effective in France and Italy in patients with type 1 diabetes.     

Retrospective study comparing healthcare costs and utilization between commercially insured patients with type 2 diabetes mellitus who are newly initiating exenatide once weekly or liraglutide in the United States

Abstract

Objective:

To compare healthcare costs and utilization between commercially insured patients with type 2 diabetes mellitus (T2DM) in the United States newly initiating exenatide once weekly (QW) or liraglutide.     

Cost-utility of exenatide once weekly compared with insulin glargine in patients with type 2 diabetes in the UK

Abstract

Objective:

To compare the cost-utility of exenatide once weekly (EQW) and insulin glargine in patients with type 2 diabetes in the United Kingdom (UK).

Research design and methods:

The IMS CORE Diabetes Model was used to project clinical and economic outcomes for patients with type 2 diabetes treated with EQW or insulin glargine. Treatment effects and patient baseline characteristics (mean age: 58 years, mean glycohaemoglobin: 8.3%) were taken from the DURATION-3 study. Unit costs and health state utility values were derived from published sources. As the price of EQW is not yet known, the prices of two currently available glucagon-like peptide-1 products were used as benchmarks. To reflect diabetes progression, patients started on EQW switched to insulin glargine after 5 years. The analysis was conducted from the perspective of the UK National Health Service over a time horizon of 50 years with costs and outcomes discounted at 3.5%. Sensitivity analyses explored the impact of changes in input data and assumptions and investigated the cost utility of EQW in specific body mass index (BMI) subgroups.

Main outcome measures:

Incremental cost-effectiveness ratio (ICER) for EQW compared with insulin glargine.

Results:

At a price equivalent to liraglutide 1.2?mg, EQW was more effective and more costly than insulin glargine, with a base case ICER of £10,597 per quality-adjusted life-year (QALY) gained. EQW was associated with an increased time to development of any diabetes-related complication of 0.21 years, compared with insulin glargine. Three BMI subgroups investigated (<30, 30–35 and >35?kg/m²) reported ICERs for EQW compared with insulin glargine ranging from £9425 to £12,956 per QALY gained.

Conclusions:

At the prices investigated, the cost per QALY gained for EQW when compared with insulin glargine in type 2 diabetes in the UK setting, was within the range normally considered cost effective by NICE. Cost effectiveness in practice will depend on the final price of EQW and the extent to which benefits observed in short-term randomised trials are replicated in long-term use.     

Evaluating drug cost per responder and number needed to treat associated with lixisenatide on top of glargine when compared to rapid-acting insulin intensification regimens on top of glargine,in patients with type 2 diabetes in the UK,Italy, and Spain

Objectives: This study investigated the cost per responder and number needed to treat (NNT) in type 2 diabetes mellitus (T2DM) patients for lixisenatide compared to insulin intensification regimens using composite endpoints in the UK, Italy, and Spain.

Methods: Efficacy and safety outcomes were obtained from GetGoal Duo-2, a 26-week phase 3 trial comparing lixisenatide vs insulin glulisine (IG) once daily (QD) and three times daily (TID). Response at week 26 was extrapolated to 52 weeks, assuming a maintained treatment effect, based on long-term evidence in other T2DM populations. Responders were defined using composite end-points, based on an HbA1c threshold and/or no weight gain and/or no hypoglycemia. The HbA1c threshold was varied in sensitivity analyses. Annual treatment costs were estimated in euros (1 GBP?=?1.26 EUR), including drug acquisition and resource use costs. Cost per responder was computed by dividing annual treatment costs per patient by the proportion of responders.

Results: Lixisenatide was associated with the lowest cost per responder for all composite end-points that included a weight-related component. For the main composite end-point of HbA1c ≤7.5% AND no weight gain AND no symptomatic hypoglycemia, cost per responder results were: UK: 6,867€, 8,746€, and 12,410€; Italy: 7,057€, 9,160€, and 12,844€; Spain: 8,370€, 11,365€, and 17,038€, for lixisenatide, IG QD, and TID, respectively. The NNT analysis showed that, for every 6.85 and 5.86 patients treated with lixisenatide, there was approximately one additional responder compared to IG QD and TID, respectively.

Limitations: A limitation of the clinical inputs is the lack of 52-week trial data from GetGoal Duo-2, which led to the assumption of a maintained treatment effect from week 26 to 52.

Conclusions: This analysis suggests lixisenatide is an efficient economic resource allocation in the UK, Italy, and Spain.     

Evaluation of the long-term cost-effectiveness of liraglutide therapy for patients with type 2 diabetes in France

Objectives:

The present study aimed to compare the projected long-term clinical and cost implications associated with liraglutide, sitagliptin and glimepiride in patients with type 2 diabetes mellitus failing to achieve glycemic control on metformin monotherapy in France.

Methods:

Clinical input data for the modeling analysis were taken from two randomized, controlled trials (LIRA-DPP4 and LEAD-2). Long-term (patient lifetime) projections of clinical outcomes and direct costs (2013 Euros; €) were made using a validated computer simulation model of type 2 diabetes. Costs were taken from published France-specific sources. Future costs and clinical benefits were discounted at 3% annually. Sensitivity analyses were performed.

Results:

Liraglutide was associated with an increase in quality-adjusted life expectancy of 0.25 quality-adjusted life years (QALYs) and an increase in mean direct healthcare costs of €2558 per patient compared with sitagliptin. In the comparison with glimepiride, liraglutide was associated with an increase in quality-adjusted life expectancy of 0.23 QALYs and an increase in direct costs of €4695. Based on these estimates, liraglutide was associated with an incremental cost-effectiveness ratio (ICER) of €10,275 per QALY gained vs sitagliptin and €20,709 per QALY gained vs glimepiride in France.

Conclusion:

Calculated ICERs for both comparisons fell below the commonly quoted willingness-to-pay threshold of €30,000 per QALY gained. Therefore, liraglutide is likely to be cost-effective vs sitagliptin and glimepiride from a healthcare payer perspective in France.     

Laparoscopic adjustable gastric banding vs standard medical management in obese patients with type 2 diabetes: a budget impact analysis in the UK

Abstract

Objective:

To evaluate the financial consequences of using laparoscopic adjustable gastric banding (LAGB) in place of standard medical management (SMM) in obese patients with type 2 diabetes from a UK healthcare payer perspective.     

Incremental costs associated with myocardial infarction and stroke in patients with type 2 diabetes mellitus: an overview for economic modeling

Objective:

To identify cost estimates related to myocardial infarction (MI) or stroke in patients with type 2 diabetes mellitus (T2DM) for use in economic models.

Methods:

A systematic literature review was conducted. Electronic databases and conference abstracts were screened against inclusion criteria, which included studies performed in patients who had T2DM before experiencing an MI or stroke. Primary cost studies and economic models were included. Costs were converted to 2012 pounds sterling.

Results:

Fifty-four studies were identified: 13 primary cost studies and 41 economic evaluations using secondary sources for complication costs. Primary studies provided costs from 10 countries. Estimates for a fatal event ranged from £2482–£5222 for MI and from £4900–£6694 for stroke. Costs for the year a non-fatal event occurred ranged from £5071–£29,249 for MI and from £5171–£38,732 for stroke. Annual follow-up costs ranged from £945–£1616 for an MI and from £4704–£12,926 for a stroke. Economic evaluations from 12 countries were identified, and costs of complications showed similar variability to the primary studies.

Discussion:

The costs identified within primary studies varied between and within countries. Many studies used costs estimated in studies not specific to patients with T2DM. Data gaps included a detailed breakdown of resource use, which affected the ability to compare data across countries.

Conclusions:

In the development of economic models for patients with T2DM, the use of accurate estimates of costs associated with MI and stroke is important. When country-specific costs are not available, clear justification for the choice of estimates should be provided.     

Comparison of utilization,cost, adherence,and hypoglycemia in patients with type 2 diabetes initiating rapid-acting insulin analog with prefilled pen versus vial/syringe

Abstract

Background:

Studies examining outcomes of different insulin delivery systems are limited. The objective of this study was to compare healthcare utilization, costs, adherence, and hypoglycemia rates in patients with type 2 diabetes mellitus (T2DM) initiating rapid-acting insulin analog (RAIA) using prefilled pen versus vial/syringe.

Methods:

A retrospective analysis was conducted using a US claims database (1/1/2007 to 12/31/2008). Inclusion criteria were: ≥18 years old, with T2DM, ≥12 months of continuous eligibility, and new to RAIA. Difference-in-difference analyses after propensity score matching were conducted to compare changes in outcomes from 6 months prior to and 6 months after initiating RAIA with a prefilled pen versus vial/syringe (Wilcoxon rank-sum test for costs and t-test for other outcomes). Categories of utilization and costs (2009 USD) included total and diabetes-related inpatient, outpatient, and emergency room. Adherence was measured by proportion of days covered (PDC). Hypoglycemia was identified using ICD-9-CM codes.

Results:

Baseline characteristics were similar between the prefilled pen (n?=?239) and vial/syringe (n?=?590) cohorts after matching. Adherence to RAIA was greater in the prefilled pen cohort than the vial/syringe cohort (PDC: 54.6 vs. 45.2%, p?<?0.001). While the increase in diabetes-related pharmacy costs from before to after initiating RAIA was greater in the prefilled pen cohort than the vial/syringe cohort (+$900 vs. +$607, p?<?0.001), the prefilled pen cohort was associated with greater reductions in the total diabetes-related costs (–$235 vs. +$61, p?=?0.006) and the utilization of oral anti-hyperglycemic agents (–1.3 vs. –0.7, p?=?0.016). There were no significant differences in other outcomes.

Limitations:

Claims databases do not provide optimal measures for adherence or T2DM severity, and only capture hypoglycemia events requiring clinical intervention.

Conclusion:

Initiating RAIA with a prefilled pen was associated with better adherence and greater reduction in total diabetes-related costs than a vial/syringe. There was no significant difference in total healthcare costs.     

Distribution and drivers of costs in type 2 diabetes mellitus treated with oral hypoglycemic agents: a retrospective claims data analysis

Objective:

To describe the distribution of costs and to identify the drivers of high costs among adult patients with type 2 diabetes mellitus (T2DM) receiving oral hypoglycemic agents.

Methods:

T2DM patients using oral hypoglycemic agents and having HbA1c test data were identified from the Truven MarketScan databases of Commercial and Medicare Supplemental insurance claims (2004–2010). All-cause and diabetes-related annual direct healthcare costs were measured and reported by cost components. The 25% most costly patients in the study sample were defined as high-cost patients. Drivers of high costs were identified in multivariate logistic regressions.

Results:

Total 1-year all-cause costs for the 4104 study patients were $55,599,311 (mean cost per patient?=?$13,548). Diabetes-related costs accounted for 33.8% of all-cause costs (mean cost per patient?=?$4583). Medical service costs accounted for the majority of all-cause and diabetes-related total costs (63.7% and 59.5%, respectively), with a minority of patients incurring >80% of these costs (23.5% and 14.7%, respectively). Within the medical claims, inpatient admission for diabetes-complications was the strongest cost driver for both all-cause (OR?=?13.5, 95% CI?=?8.1–23.6) and diabetes-related costs (OR?=?9.7, 95% CI?=?6.3–15.1), with macrovascular complications accounting for most inpatient admissions. Other cost drivers included heavier hypoglycemic agent use, diabetes complications, and chronic diseases.

Limitations:

The study reports a conservative estimate for the relative share of diabetes-related costs relative to total cost. The findings of this study apply mainly to T2DM patients under 65 years of age.

Conclusions:

Among the T2DM patients receiving oral hypoglycemic agents, 23.5% of patients incurred 80% of the all-cause healthcare costs, with these costs being driven by inpatient admissions, complications of diabetes, and chronic diseases. Interventions targeting inpatient admissions and/or complications of diabetes may contribute to the decrease of the diabetes economic burden.