Impact of diabetes on costs before and after major lower extremity amputations in Germany

Impact of diabetes on medical costs in the pre- and postoperative year of lower extremity amputations in Belgium

AIMS

To compare the medical costs of individuals undergoing lower extremity amputation (LEA) in Belgium with those of amputation-free individuals.

METHODS

Belgian citizens undergoing LEAs in 2014 were identified. The median costs per capita in euros for the 12 months preceding and following minor and major LEAs were compared with those of matched amputation-free individuals.

RESULTS

A total of 3324 Belgian citizens underwent LEAs (2295 minor, 1029 major), 2130 of them had diabetes. The comparison group included 31,716 individuals. Amputation was associated with high medical costs (individuals with diabetes: major LEA €49,735, minor LEA €24,243, no LEA €2,877 in the year preceding amputation; €45,740, €21,445 and €2,284, respectively, in the post-amputation year). Significantly higher costs were observed in the individuals with (versus without) diabetes in all groups. This difference diminished with higher amputation levels. Individuals undergoing multiple LEAs generated higher costs (individuals with diabetes: €39,313-€89,563 when LEAs preceded index amputation; €46,629-€92,877 when LEAs followed index amputation). Individuals dying in the year after a major LEA generated remarkably lower costs.

CONCLUSIONS

LEA-related medical costs were high. Diabetes significantly impacted costs, but differences in costs diminished with higher amputation levels. Individuals with multiple amputations generated the highest costs.

A narrative review of the epidemiology and economics of chronic wounds

Chronic wounds have a debilitating effect on the quality of life of many individuals, and the large economic impact on health system budgets warrants greater attention in policy making and condition management than is currently evident. The aim of this narrative review is to summarize the nature and extent of the chronic wound problem that confronts health systems across the world. The first section is used to highlight the underlying epidemiology relating to chronic wounds, while the second explores the economic costs associated with them and the relative efficiency of measures designed to manage them.

Using machine learning to identify diabetes patients with canagliflozin prescriptions at high-risk of lower extremity amputation using real-world data

AIMS

Canagliflozin, a sodium-glucose cotransporter 2 inhibitor indicated for lowering glucose, has been increasingly used in diabetes patients because of its beneficial effects on cardiovascular and renal outcomes. However, clinical trials have documented an increased risk of lower extremity amputations (LEA) associated with canagliflozin. We applied machine learning methods to predict LEA among diabetes patients treated with canagliflozin.

METHODS

Using claims data from a 5% random sample of Medicare beneficiaries, we identified 13 904 diabetes individuals initiating canagliflozin between April 2013 and December 2016. The samples were randomly and equally split into training and testing sets. We identified 41 predictor candidates using information from the year prior to canagliflozin initiation, and applied four machine learning approaches (elastic net, least absolute shrinkage and selection operator [LASSO], gradient boosting machine and random forests) to predict LEA risk after canagliflozin initiation.

RESULTS

The incidence rate of LEA was 0.57% over a median 1.5 years follow-up. LASSO produced the best prediction, yielding a C-statistic of 0.81 (95% CI: 0.76, 0.86). Among individuals categorized in the top 5% of the risk score, the actual incidence rate of LEA was 3.74%. Among the 16 factors selected by LASSO, history of LEA [adjusted odds ratio (aOR): 33.6 (13.8, 81.9)] and loop diuretic use [aOR: 3.6 (1.8,7.3)] had the strongest associations with LEA incidence.

CONCLUSIONS

Our machine learning model efficiently predicted the risk of LEA among diabetes patients undergoing canagliflozin treatment. The risk score may support optimized treatment decisions and thus improve health outcomes of diabetes patients.

Impact of Time to Receipt of Prosthesis on Total Healthcare Costs 12 Months Postamputation

OBJECTIVE

The objective was to assess the impact of a prosthesis and the timing of prosthesis receipt on total direct healthcare costs in the 12-mo postamputation period.

DESIGN

Data on patients with lower limb amputation (n = 510) were obtained from a commercial claims database for retrospective cohort analysis. Generalized linear multivariate modeling was used to determine differences in cost between groups according to timing of prosthesis receipt compared with a control group with no prosthesis.

RESULTS

Receipt of a prosthesis between 0 and 3 mos post lower limb amputation yielded a reduced total cost by approximately 0.23 in log scale within 12 mos after amputation when compared with the no-prosthesis group. Despite the included costs of a prosthesis, individuals who received a prosthesis either at 4-6 mos postamputation or 7-9 mos postamputation incurred costs similar to the no-prosthesis group.

CONCLUSION

Earlier receipt of a prosthesis is associated with reduced spending in the 12 mos postamputation of approximately $25,000 compared with not receiving a prosthesis. The results of this study suggest that not providing or delaying the provision of a prosthesis increases costs by about 25%.

Health Care Costs Associated With Macrovascular, Microvascular, and Metabolic Complications of Type 2 Diabetes Across Time: Estimates From a Population-Based Cohort of More Than 0.8 Million Individuals With Up to 15 Years of Follow-up

OBJECTIVE

Developing country-specific unit-cost catalogs is a key area for advancing economic research to improve medical and policy decisions. However, little is known about how health care costs vary by type 2 diabetes (T2D) complications across time in Asian countries. We sought to quantify the economic burden of various T2D complications in Taiwan.

RESEARCH DESIGN AND METHODS

A nationwide, population-based, longitudinal study was conducted to analyze 802,429 adults with newly diagnosed T2D identified during 1999-2010 and followed up until death or 31 December 2013. Annual health care costs associated with T2D complications were estimated, with multivariable generalized estimating equation models adjusted for individual characteristics.

RESULTS

The mean annual health care cost was $281 and $298 (2017 U.S. dollars) for a male and female, respectively, diagnosed with T2D at age <50 years, with diabetes duration of <5 years, and without comorbidities, antidiabetic treatments, and complications. Depression was the costliest comorbidity, increasing costs by 64-82%. Antidiabetic treatments increased costs by 72-126%. For nonfatal complications, costs increased from 36% (retinopathy) to 202% (stroke) in the event year and from 13% (retinopathy or neuropathy) to 49% (heart failure) in subsequent years. Costs for the five leading costly nonfatal subtype complications increased by 201-599% (end-stage renal disease with dialysis), 37-376% (hemorrhagic/ischemic stroke), and 13-279% (upper-/lower-extremity amputation). For fatal complications, costs increased by 1,784-2,001% and 1,285-1,584% for cardiovascular and other-cause deaths, respectively.

CONCLUSIONS

The cost estimates from this study are crucial for parameterizing diabetes economic simulation models to quantify the economic impact of clinical outcomes and determine cost-effective interventions.

Health Care Costs Associated With Incident Complications in Patients With Type 2 Diabetes in Germany

OBJECTIVE

The aim of this study is to provide reliable regression-based estimates of costs associated with different type 2 diabetes complications.

RESEARCH DESIGN AND METHODS

We used nationwide statutory health insurance (SHI) data from 316,220 patients with type 2 diabetes. Costs for inpatient and outpatient care, pharmaceuticals, rehabilitation, and nonmedical aids and appliances were assessed in the years 2013-2015. Quarterly observations are available for each year. We estimated costs (in 2015 euro) for complications using a generalized estimating equations model with a normal distribution adjusted for age, sex, occurrence of different complications, and history of complications at baseline, 2012. Two- and threefold interactions were included in an extended model.

RESULTS

The base case model estimated total costs in the quarter of event for the example of a 60- to 69-year-old man as follows: diabetic foot €1,293, amputation €14,284, retinopathy €671, blindness €2,933, nephropathy €3,353, end-stage renal disease (ESRD) €22,691, nonfatal stroke €9,769, fatal stroke €11,176, nonfatal myocardial infarction (MI)/cardiac arrest (CA) €8,035, fatal MI/CA €8,700, nonfatal ischemic heart disease (IHD) €6,548, fatal IHD €20,942, chronic heart failure €3,912, and angina pectoris €2,695. In the subsequent quarters, costs ranged from €681 for retinopathy to €6,130 for ESRD.

CONCLUSIONS

Type 2 diabetes complications have a significant impact on total health care costs in the SHI system, not only in the quarter of event but also in subsequent years. Men and women from different age-groups differ in their costs for complications. Our comprehensive estimates may support the parametrization of diabetes models and help clinicians and policy makers to quantify the economic burden of diabetes complications in the context of new prevention and treatment programs.

Lower-extremity amputations in people with and without diabetes in Germany, 2008-2012 - an analysis of more than 30 million inhabitants

Background and purpose

Lower-extremity amputations (LEAs) in people with diabetes are associated with reduced quality of life and increased health care costs. Detailed knowledge on amputation rates (ARs) is of utmost importance for future health care and economics strategies. We conducted the present cohort study in order to estimate the incidences of LEA as well as relative and attributable risk due to diabetes and to investigate time trends for the period 2008–2012.

Methods

On the basis of the administrative data from three large branches of German statutory health insurers, covering ~34 million insured people nationwide (about 40% of the German population), we estimated age-sex-standardized AR (first amputation per year) in the populations with and without diabetes for any, major, and minor LEAs. Time trends were analyzed using Poisson regression.

Results

A total of 108,208 individuals (diabetes: 67.3%; mean age 72.6 years) had at least one amputation. Among people with diabetes, we observed a significant reduction in major and minor ARs during 2008–2012 from 81.2 (95% CI 77.5–84.9) to 58.4 (55.0–61.7), and from 206.1 (197.3–214.8) to 177.0 (169.7–184.4) per 100,000 person-years, respectively. Among people without diabetes, the major AR decreased significantly from 14.3 (13.9–14.8) to 11.6 ([11.2–12.0], 12.0), whereas the minor AR increased from 15.8 (15.3–16.3) to 17.0 (16.5–17.5) per 100,000 person-years. The relative risk (RR) comparing the diabetic with the nondiabetic populations decreased significantly for both major and minor LEAs (4% and 5% annual reduction, respectively).

Conclusion

In this large nationwide population, we still found higher major and minor ARs among people with diabetes compared with those without diabetes. However, AR and RR of major and minor LEAs in the diabetic compared with the nondiabetic population decreased significantly during the study period, confirming a positive trend that has been observed in smaller and regional studies in recent years.

DIRECT COSTS OF TYPE 2 DIABETES: A BRAZILIAN COST-OF-ILLNESS STUDY

Objectives:The aim of this study was to evaluate the direct costs of type 2 diabetes mellitus patients treated in a Brazilian public hospital.

Methods:This was an exploratory retrospective cost-of-illness study with quantitative approach, using medical records of patients treated in a public hospital (2012–14), with at least one consultation over a period of 12 months. Data on patient's profile, exams, number of consultations, medications, hospitalizations, and comorbidities were collected. The cost per patient per year (pppy) was calculated as well as the costs related to glycated hemoglobin (HbA1c) values, using thresholds of 7 and 8 percent.

Results:Data of 726 patients were collected with mean age of 62 ± 11 years (68.3 percent female). A total of 67.1 percent presented HbA1c > 7 percent and 44.9 percent > 8 percent. The median cost of diabetes was United States dollar (USD) 197 pppy. The median costs of medication were USD 152.49 pppy, while costs of exams and consultations were USD 40.57 pppy and 8.70 pppy, respectively. Thirty-eight patients (4 percent) were hospitalized and presented a median cost of 3,656 per patient per hospitalization with a cost equivalent to 53.1 percent of total expenses. Total costs of patients with HbA1c ≤ 7 percent were lower for this group and also costs of medications and consultations, whereas for patients with HbA1c ≤ 8 percent, only total costs and costs of medications were lower when compared with HbA1c > 8 percent patients.

Conclusions:Medications and hospitalizations were the major contributor of diabetes expenses. Preventing T2DM, or reducing its complications through adequate control, may help avoid the substantial costs related to this disease.

Systemic vasculitis is associated with a higher risk of lower extremity amputation in patients with severe peripheral arterial occlusive disease: a secondary analysis of a nationwide, population-based health claims database

Previous research has shown that diabetes mellitus increases the risk of lower extremity amputation in patients with peripheral arterial occlusive disease. However, to our knowledge, no studies have investigated whether systemic autoimmune disease, in particular systemic vasculitis is associated with a higher risk of lower extremity amputation in these patients. To investigate the association between systemic autoimmune disease and lower extremity amputation in patients with severe peripheral arterial occlusive disease based on a secondary analysis of a nationwide, population-based health claims database. Using the inpatient datafile of the Taiwan's National Health Insurance Research Database (NHIRD), we identified 432 patients with severe peripheral arterial occlusive disease that required hospitalization between 2000 and 2012. We also identified patients who had undergone lower extremity amputation and their comorbidities using the same datafile. The risk of lower extremity amputation was assessed using multiple logistic regression analysis, adjusting for age, sex, insured amount, the urbanization level of residence, and the presence of comorbidities. Among patients with severe peripheral arterial occlusive disease, those with systemic vasculitis exhibited a significant higher risk of lower extremity amputation (adjusted odds ratio [aOR] = 6.82, p < 0.001). Diabetes mellitus (aOR = 4.90, p < 0.001) and chronic obstructive pulmonary disease (aOR = 2.87, p = 0.007) were also significantly associated with a higher risk of lower extremity amputation. Among patients with severe peripheral arterial occlusive disease, a significantly higher risk of lower extremity amputation was observed in those with systemic vasculitis.

Annual direct medical costs associated with diabetes-related complications in the event year and in subsequent years in Hong Kong

AIM

To develop models to estimate the direct medical costs associated with diabetes-related complications in the event year and in subsequent years.

METHODS

The public direct medical costs associated with 13 diabetes-related complications were estimated among a cohort of 128 353 people with diabetes over 5 years. Private direct medical costs were estimated from a cross-sectional survey among 1825 people with diabetes. We used panel data regression with fixed effects to investigate the impact of each complication on direct medical costs in the event year and subsequent years, adjusting for age and co-existing complications.

RESULTS

The expected annual public direct medical cost for the baseline case was US$1,521 (95% CI 1,518 to 1,525) or a 65-year-old person with diabetes without complications. A new lower limb ulcer was associated with the biggest increase, with a multiplier of 9.38 (95% CI 8.49 to 10.37). New end-stage renal disease and stroke increased the annual medical cost by 5.23 (95% CI 4.70 to 5.82) and 5.94 (95% CI 5.79 to 6.10) times, respectively. History of acute myocardial infarction, congestive heart failure, stroke, end-stage renal disease and lower limb ulcer increased the cost by 2-3 times. The expected annual private direct medical cost of the baseline case was US$187 (95% CI 135 to 258) for a 65-year-old man without complications. Heart disease, stroke, sight-threatening diabetic retinopathy and end-stage renal disease increased the private medical costs by 1.5 to 2.5 times.

CONCLUSIONS

Wide variations in direct medical cost in event year and subsequent years across different major complications were observed. Input of these data would be essential for economic evaluations of diabetes management programmes.

Incidence of lower extremity amputations in the diabetic compared with the non-diabetic population: A systematic review

Lower extremity amputation (LEA) in patients with diabetes results in high mortality, reduced quality of life, and increased medical costs. Exact data on incidences of LEA in diabetic and non-diabetic patients are important for improvements in preventative diabetic foot care, avoidance of fatal outcomes, as well as a solid basis for health policy and the economy. However, published data are conflicting, underlining the necessity for the present systematic review of population-based studies on incidence, relative risks and changes of amputation rates over time. It was conducted according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines. Nineteen out of 1582 studies retrieved were included in the analysis. The incidence of LEA in the diabetic population ranged from 78 to 704 per 100,000 person-years and the relative risks between diabetic and non-diabetic patients varied between 7.4 and 41.3. Study designs, statistical methods, definitions of major and minor amputations, as well as the methods to identify patients with diabetes differed greatly, explaining in part these considerable differences. Some studies found a decrease in incidence of LEA as well as relative risks over time. This obvious lack of evidence should be overcome by new studies using a standardized design with comparable methods and definitions.

The hospitalization profiles of patients with or without diabetes treated for nontraumatic lower extremity amputation in Ribeirão Preto, São Paulo State, Brazil, 2001-2008

The aim of this retrospective study was to assess the hospitalizations of patients with or without diabetes mellitus (DM) who underwent nontraumatic lower extremity amputation (NLEA) with regard to demographic and hospitalization-related variables. It is a high proportion of hospital beds in developing countries, for patients with diabetes mellitus with lower extremity complications. Nontraumatic amputations of lower extremities rates is an important indicator to assess the effectiveness of efforts to reduce chronic complications related to diabetic foot.A total of 2,296 hospital admissions were analyzed with regard to gender, age, length of stay, type of financing, origin, diagnosis, number of hospital admissions and readmissions, and hospitalization outcome from 2001 to 2008 in a municipality of Southeast Brazil. The association between the independent variables and the number of hospitalizations of patients with or without diabetes was assessed using chi-square tests for gender, type of financing, and hospitalization outcome and using the Mann-Whitney U test for age and length of stay. A total of 58% were patients without diabetes, 62.6% were male, 74.5% were treated at a public health care service, and 7.6% died. The mean age was 62.7 years, the mean length of stay was of 9.5 days, and the mean number of readmissions was 2.29 times. The length of stay was higher (P < .001), and the number of men was lower (P = .001) among the patients with diabetes who were hospitalized compared with patients without diabetes.The number of hospitalizations related to NLEA increased among patients with diabetes but reduced among those without diabetes between 2001 and 2008.

Study of Disease Progression and Relevant Risk Factors in Diabetic Foot Patients Using a Multistate Continuous-Time Markov Chain Model

The diabetic foot is a lifelong disease. The longer patients with diabetes and foot ulcers are observed, the higher the likelihood that they will develop comorbidities that adversely influence ulcer recurrence, amputation and survival (for example peripheral arterial disease, renal failure or ischaemic heart disease). The purpose of our study was to quantify person and limb-related disease progression and the time-dependent influence of any associated factors (present at baseline or appearing during observation) based on which effective prevention and/or treatment strategies could be developed. Using a nine-state continuous-time Markov chain model with time-dependent risk factors, all living patients were divided into eight groups based on their ulceration (previous or current) and previous amputation (none, minor or major) status. State nine is an absorbing state (death). If all transitions are fully observable, this model can be decomposed into eight submodels, which can be analyzed using the methods of survival analysis for competing risks. The dependencies of the risk factors (covariates) were included in the submodels using Cox-like regression. The transition intensities and relative risks for covariates were calculated from long-term data of patients with diabetic foot ulcers collected in a single specialized center in North-Rhine Westphalia (Germany). The detected estimates were in line with previously published, but scarce, data. Together with the interesting new results obtained, this indicates that the proposed model may be useful for studying disease progression in larger samples of patients with diabetic foot ulcers.

HbA1c and Lower Extremity Amputation Risk in Patients With Diabetes

In this meta-analysis, we aimed to assess glycosylated hemoglobin (HbA1c) level and lower extremity amputation (LEA) risk in patients with diabetes. Systematic computerized searches of the PubMed and Web of Knowledge were performed. We compared HbA1c level between groups with LEA and without LEA by meta-analysis; we also examined the dose–response relationship between HbA1c level and LEA risk. Sixteen studies were included in the meta-analysis. Eleven studies with 43 566 patients compared HbA1c between groups with and without LEA. The mean HbA1c (%) ranged from 8.3 to 12.5 in the group with LEA and from 7.4 to 11.3 in the group without LEA. The pooled weighted mean difference was 1.110 (95% confidence interval = 0.510-1.709; Z = 3.63, P = .008). The funnel plot was symmetrical, and Begg’s test ( z = 0.00, P = 1.000) and Egger’s test ( t = −0.02, P = .984) suggested no significant publication bias. Six studies with 109 933 patients included in the dose–response meta-analysis. The LEA incidence ranged from 0.3% to 14.6% between different HbA1c levels. Dose–response meta-analysis showed statistically significant association between HbA1c and LEA risk (χ2 = 65.51, P = .000). In linear model, the odds ratio for LEA incidence was 1.229 (95% confidence interval = 1.169-1.292) for every 1% HbA1c increase. In the spline model, the odds ratio of LEA risk increased with HbA1c levels, especially when HbA1c ranged from 5% to 9%. Our meta-analysis indicates that high level of HbA1c is an important risk factor for LEA in patients with diabetes. This evidence supports the strategy for lowering glucose levels to reduce amputation in patients with diabetes.

Incidence of lower extremity amputation in the diabetic compared to the non-diabetic population: a systematic review protocol

BACKGROUND

Diabetic individuals have a largely increased risk of lower extremity amputation (LEA) compared with non-diabetic patients. Prior systematic reviews of incidence of LEA have some limitations with respect to lack of consensus in the definition of LEA, level of LEA (all, major, minor), and definition of source population (general population or population with diabetes at risk). The purpose of our review is to evaluate the incidence of LEA in the diabetic population and its differences with regard to sex, ethnicity, age, and regions; to compare the incidence rate (IR) in the diabetic and non-diabetic population; and to investigate time trends.

METHODS/DESIGN

We will perform a systematic literature search in MEDLINE, Embase, Web of Knowledge, and publisher databases such as Journals@OVID and ScienceDirect. We will develop comprehensive systematic search strategies according to established guidelines for meta-analyses of observational studies in epidemiology (the MOOSE group). Two authors will independently screen abstracts and full text of all references on the basis of inclusion criteria with respect to types of study, types of population, and the main outcome. We will exclude studies if they report solely incidences of LEA among persons with diabetes mellitus when referring to the total population (diabetic and non-diabetic) and not exclusively to the diabetic population. Data extraction and assessment of risk of bias will be undertaken by two review authors working independently. We will assess incidence rate (IR) or cumulative incidence (CumI), relative risk of amputations comparing the diabetic to non-diabetic populations, cause of LEA, and type of diabetes. If we find subsets of studies to be homogeneous enough, we will perform meta-analyses for incidence rates by Poisson generalized linear mixed models (GLMM).

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42015017809.