Direct and indirect costs among employees with diabetic retinopathy in the United States

Variations in Electronic Health Record-Based Definitions of Diabetic Retinopathy Cohorts: A Literature Review and Quantitative Analysis

Purpose

Use of the electronic health record (EHR) has motivated the need for data standardization. A gap in knowledge exists regarding variations in existing terminologies for defining diabetic retinopathy (DR) cohorts. This study aimed to review the literature and analyze variations regarding codified definitions of DR.

Design

Literature review and quantitative analysis.

Subjects

Published manuscripts.

Methods

Four graders reviewed PubMed and Google Scholar for peer-reviewed studies. Studies were included if they used codified definitions of DR (e.g., billing codes). Data elements such as author names, publication year, purpose, data set type, and DR definitions were manually extracted. Each study was reviewed by ≥ 2 authors to validate inclusion eligibility. Quantitative analyses of the codified definitions were then performed to characterize the variation between DR cohort definitions.

Main Outcome Measures

Number of studies included and numeric counts of billing codes used to define codified cohorts.

Results

In total, 43 studies met the inclusion criteria. Half of the included studies used datasets based on structured EHR data (i.e., data registries, institutional EHR review), and half used claims data. All but 1 of the studies used billing codes such as the International Classification of Diseases 9th or 10th edition (ICD-9 or ICD-10), either alone or in addition to another terminology for defining disease. Of the 27 included studies that used ICD-9 and the 20 studies that used ICD-10 codes, the most common codes used pertained to the full spectrum of DR severity. Diabetic retinopathy complications (e.g., vitreous hemorrhage) were also used to define some DR cohorts.

Conclusions

Substantial variations exist among codified definitions for DR cohorts within retrospective studies. Variable definitions may limit generalizability and reproducibility of retrospective studies. More work is needed to standardize disease cohorts.

Financial Disclosures

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

The Economic Burden of Diabetic Retinopathy in Jordan: Cost Analysis and Associated Factors

Objective

Diabetic retinopathy (DR) is the leading cause of visual loss worldwide in patients with diabetes mellitus (DM). The aims of our study are to describe the costs associated with (DR) and to evaluate its economic impact in Jordan.

Methods

Retrospectively, we included all patients with DM and classified them according to the severity of DR. Data regarding medical history, ophthalmic history, stage of DR, presence of DME, and the ophthalmic procedures and operations were collected. The total DR-related cost was measured as a direct medical cost for the outpatient and inpatient services.

Results

Two hundred and twenty-nine patients were included in the study. Only 49.7% of the patients presented without DR, and 21% presented with diabetic macular edema (DME) unilaterally or bilaterally. The DR-related cost was significantly associated with insulin-based regimens, longer duration of DM, higher HbA1c levels, worse stage of DR at presentation, the presence of DME at presentation, the presence of glaucoma, and increased mean number of intravitreal injections, laser sessions, and surgical operations. Multivariate analysis should the presenting stage of DR, presence of DME, and the presence of DME be the independent factors affecting the DR-related cost.

Conclusion

This study is the first study to be conducted in Jordan and encourages us to establish a screening program for DR for earlier detection and treatment. DM control and treatment compliance will reduce the heavy costs of the already exhausted healthcare and financial system.

Healthcare Resource Utilization and Costs in an At-Risk Population With Diabetic Retinopathy

Purpose

Several investigators have suggested the cost-effectiveness of earlier screening, management of risk factors, and early treatment for diabetic retinopathy (DR). We aimed to evaluate the extent of health care utilization and cost of delayed care by insurance type in a vulnerable patient population.

Methods

A retrospective analysis of patients with DR was conducted using electronic medical record (EMR) data from January 2014 to December 2020 at Denver Health Medical Center, a safety net institution. Patients were classified by disease severity and insurance status. DR-specific costs were assessed via Current Procedural Terminology (CPT) codes over a 24-month follow-up period.

Results

Among the 313 patients, a higher proportion of non-English speaking patients were uninsured. Rates of proliferative DR at presentation differed across insurance groups (62% of uninsured, 42% of discount plan, and 33% of Medicare/Medicaid, P = 0.016). There was a significant difference in the total median cost between discount plan patients ($1258, interquartile range [IQR] = $0 - $5901) and both Medicare patients ($751, IQR = $0, $7148, P = 0.037) and Medicaid patients ($593, IQR = $0 - $6299, P = 0.025).

Conclusions

There were higher rates of proliferative DR at presentation among the uninsured and discount plan patients and greater total median cost in discount plan patients compared to Medicare or Medicaid. These findings prioritize mitigating gaps in insurance coverage and barriers to preventative care among vulnerable populations.

Translational Relevance

Advanced diabetic disease and increased downstream health care utilization and cost vary across insurance type, suggesting improved access to preventative care is needed in these specific at-risk populations.

Optical coherence tomography in the management of diabetic macular oedema

Diabetic macular oedema (DMO) is the major cause of visual impairment in people with diabetes. Optical coherence tomography (OCT) is now the most widely used modality to assess presence and severity of DMO. DMO is currently broadly classified based on the involvement to the central 1 mm of the macula into non-centre or centre involved DMO (CI-DMO) and DMO can occur with or without visual acuity (VA) loss. This classification forms the basis of management strategies of DMO. Despite years of research on quantitative and qualitative DMO related features assessed by OCT, these do not fully inform physicians of the prognosis and severity of DMO relative to visual function. Having said that, recent research on novel OCT biomarkers development and re-defined classification of DMO show better correlation with visual function and treatment response. This review summarises the current evidence of the association of OCT biomarkers in DMO management and its potential clinical importance in predicting VA and anatomical treatment response. The review also discusses some future directions in this field, such as the use of artificial intelligence to quantify and monitor OCT biomarkers and retinal fluid and identify phenotypes of DMO, and the need for standardisation and classification of OCT biomarkers to use in future clinical trials and clinical practice settings as prognostic markers and secondary treatment outcome measures in the management of DMO.

Prevalence and predictors for being unscreened for diabetic retinopathy: a population-based study over a decade

OBJECTIVE

To determine the population-level predictors for being unscreened for diabetic retinopathy (DR) among individuals with diabetes in a developed country.

DESIGN

A retrospective population-based repeated-cross-sectional study.

PARTICIPANTS

All individuals with diabetes (types 1 and 2) aged ≥20 years in the universal health care system in Ontario were identified in the 2011-2013 and 2017-2019 time periods.

METHODS

The Mantel-Haenszel test was used for the relative risk (RR) comparison of subcategories stratified by the 2 cross-sectional time periods.

RESULTS

A total of 1 145 645 and 1 346 578 individuals with diabetes were identified in 2011-2013 and 2017-2019, respectively. The proportion of patients unscreened for DR declined very slightly from 35% (n = 405 967) in 2011-2013 to 34% (n = 455 027) in 2017-2019 of the population with diabetes (RR = 0.967; 95% CI, 0.964-0.9693; p < 0.0001). Young adults aged 20-39 years of age had the highest proportion of unscreened patients (62% and 58% in 2011-2013 and 2017-2019, respectively). Additionally, those who had a lower income quintile (RR = 1.039; 95% CI, 1.036-1.044; p < 0.0001), were recent immigrants (RR = 1.286; 95% CI, 1.280-1.293; p < 0.0001), lived in urban areas (RR = 1.149; 95% CI, 1.145-1.154; p < 0.0001), had a mental health history (RR = 1.117; 95% CI, 1.112-1.122; p < 0.0001), or lacked a connection to a primary care provider (RR = 1.656; 95% CI, 1.644-1.668; p < 0.0001) had a higher risk of being unscreened.

CONCLUSIONS

This population-based study suggests that over 1 decade, 33% of individuals with diabetes are unscreened for DR, and young age, low income, immigration, residing in a large city, mental health illness, and no primary care access are the main predictors.

Estimating the costs of blindness and moderate to severe visual impairment among people with diabetes in India

OBJECTIVES

This study provides an estimate of the annual cost of blindness and moderate to severe visual impairment (MSVI) among people with diabetes aged 40 years and above in India in the year 2019.

DESIGN

A cost of illness study.

SETTING

India.

PARTICIPANTS

People with diabetes aged 40 years and above in India in the year 2019.

PRIMARY AND SECONDARY OUTCOME MEASURES

Estimates are provided for the total costs of screening for most common vision-threatening eye conditions, treatment of these conditions, economic activity lost by these people and their family carers whose ability to work is affected, and loss of quality of life experienced by people with diabetes and blindness or MSVI.

RESULTS

It is estimated that for people with diabetes aged 40 years or above, annual screening followed by eye examination where required would cost around 42.3 billion Indian rupees (INR) (4230 crores) per year; treating sight problems around 2.87 billion INR (287 crores) per year if 20% of those needing treatment receive it; and lost economic activity around 472 billion INR (47 200 crores). Moreover, 2.86 million (0.286 crores) quality-adjusted life years (QALYs) are lost annually due to blindness and MSVI. The estimate of lost production is highly sensitive to the proportion of people with MSVI able to work and how their output compares with that of a person with no visual impairment.

CONCLUSIONS

This is the first study to estimate the cost of blindness and MSVI for people aged 40 years and over with diabetes in India. The annual cost to the Indian economy is substantial. This cost will be expected to fall if a successful screening and treatment plan is introduced in India. Further work is suggested using more robust data, when available, to estimate the loss of productivity and loss of QALYs, as this would be worthwhile.

Topical treatment of diabetic retinopathy: a systematic review

Diabetic retinopathy (DR) is the most common microvascular complication in diabetes and may cause severe visual impairment. Until late stages of DR, treatment options are limited. The aim of the present review was to investigate whether changes of DR might be influenced by topical treatment with eye drops. This systematic review included both randomized and non-randomized human clinical studies on the subject. A systematic search of PubMed Medline, Embase and Scopus databases yielded 710 studies. No inclusion criteria regarding classification of DR were defined. Reference lists as well as first authors were screened for the inclusion of additional studies. Potential bias of the randomized studies was assessed using the Cochrane Risk of Bias tool. Nineteen studies suitable for inclusion were identified. Seven studies were randomized trials. These examined 11 different pharmacological groups of drugs in DR. A favourable effect of corticosteroid eye drops in diabetic macular oedema (DMO) was reported in four studies, and another study reported a positive trend. Eye drops with non-steroidal anti-inflammatory drugs were also reported to have a favourable effect in DMO, but not in non-center involving DMO. Application of neuroprotective agents was found effective in patients with pre-existing neurodegeneration in three studies. The remaining studies of DMO and DR were heterogeneous in both designs and results. Studies on treatment of DR with topical eye drops vary with regards to patient population, interventional drugs, study design, and outcome measures. Treatment of DR with eye drops was found effective in the aforementioned cases, but there is still a need for further investigations of long-term, randomized controlled trials in any of the reported pharmacological group.

Higher rates of all-cause mortality and resource utilization during episodes-of-care for diabetic foot ulceration

AIMS

Our primary objective was to determine whether all-cause rates of mortality and resource utilization were higher during periods of diabetic foot ulceration. In support of this objective, a secondary objective was to develop and validate an episode-of-care model for diabetic foot ulceration.

METHODS

We evaluated data from the Medicare Limited Data Set between 2013 and 2019. We defined episodes-of-care by clustering diabetic foot ulcer related claims such that the longest time interval between consecutive claims in any cluster did not exceed a duration which was adjusted to match two aspects of foot ulcer episodes that are well-established in the literature: healing rate at 12 weeks, and reulceration rate following healing. We compared rates of outcomes during periods of ulceration to rates immediately following healing to estimate incidence ratios.

RESULTS

The episode-of-care model had a minimum mean relative error of 4.2% in the two validation criteria using a clustering duration of seven weeks. Compared to periods after healing, all-cause inpatient admissions were 2.8 times more likely during foot ulcer episodes and death was 1.5 times more likely.

CONCLUSIONS

A newly-validated episode-of-care model for diabetic foot ulcers suggests an underappreciated association between foot ulcer episodes and all-cause resource utilization and mortality.

Assessing financial insecurity among common eye conditions: a 2016-2017 national health survey study

Objective

To explore the prevalence and demographics of financial insecurity in individuals with eye disease in the United States.

Methods

This retrospective cross-sectional study analysed questions from the nationally representative 2016–2017 National Health Interview Survey (NHIS) with the eye conditions macular degeneration, diabetic retinopathy, glaucoma, and cataract. Data was analysed as a whole and then further analysed by condition. Evaluated topics indicated financial insecurity such as individuals reporting difficulty paying bills among eye conditions studied and by demographics.

Results

Survey responses estimated that the overall prevalence of reporting problems paying or unable to pay bills were 12.49% (95% C.I. 11.62–13.36%) among patients with eye conditions. The overall prevalence of patients delaying care was 6.77% (95% C.I. 6.17–7.36%) and 17.06% (95% C.I. 15.99–18.14%) of individuals with eye conditions reported worrying about housing payments. Multivariable logistic regression revealed that demographics who more frequently had difficulty paying medical bills include individuals age 45–64 (3.33 aOR, C.I. 2.79–3.98, p < 0.001), blacks (1.90 aOR, C.I., 1.48–2.45, p < 0.001), Hispanics (1.51 aOR, C.I. 1.07–2.12, p = 0.020), and those 100–200% of the federal poverty line (2.16 aOR, C.I. 1.76–2.66, p < 0.001) or below the poverty line (1.93 aOR, C.I. 1.48–2.53, p < 0.001).

Conclusion

There are several demographics with eye disease that self-report financial insecurity. There should be greater concern for financial insecurity among diabetic retinopathy and glaucoma patients. Ophthalmologists should consider engaging in proactive discussions with at-risk patients to reduce potential non-adherence secondary to financial insecurity.

The economic burden of diabetic retinopathy care at a tertiary eye care center in South India

Purpose:

The aim of this study was to analyze the cost and factors affecting diabetic retinopathy (DR) care in a tertiary eye care facility in South India.

Methods:

In a retrospective, observational study, we evaluated the costs incurred in DR management in each stage of retinopathy from electronic medical records. Both medical and indirect costs (transportation and boarding) were calculated.

Results:

The study evaluated 1000 consecutive patients (2000 eyes) with DR, from January to June 2019. One-third (32%; n = 321) patients were females. The median cost per patient was INR 8,214 (IQR 2,812-29,748). Cost of care was higher in patients with sight-threatening DR (STDR) compared to non-STDR (INR 31,820 vs INR 14,356, P < 0.001). Among 57.3% (n = 573;1137 eyes) of subjects who completed treatment, there was a statistically significant reduction in visual impairment (427 to 355 eyes) and blindness (<3/60) (132 to 103 eyes) from baseline (P < 0.001). The number of follow-up visits had a negative association with travel distance and socioeconomic status (P < 0.001); the positive association was seen with DR severity (P = 0.002) and total cost (P < 0.001) on regression analysis. There was a nearly 3-fold difference in the average medical cost per eye for subjects with severe visual loss (<3/60) (INR 26,270) compared to those with good vision (≥6/12) (INR 8,510).

Conclusion:

Treatment of DR benefits, but the cost of care increases with disease severity and visual impairment. Compliance to care was related to DR severity and treatment cost. Some of the barriers could be reduced with greater advocacy and reduced travel distance.

Prediction of response to anti-vascular endothelial growth factor treatment in diabetic macular oedema using an optical coherence tomography-based machine learning method

PURPOSE

To predict the anti-vascular endothelial growth factor (VEGF) therapeutic response of diabetic macular oedema (DME) patients from optical coherence tomography (OCT) at the initiation stage of treatment using a machine learning-based self-explainable system.

METHODS

A total of 712 DME patients were included and classified into poor and good responder groups according to central macular thickness decrease after three consecutive injections. Machine learning models were constructed to make predictions based on related features extracted automatically using deep learning algorithms from OCT scans at baseline. Five-fold cross-validation was applied to optimize and evaluate the models. The model with the best performance was then compared with two ophthalmologists. Feature importance was further investigated, and a Wilcoxon rank-sum test was performed to assess the difference of a single feature between two groups.

RESULTS

Of 712 patients, 294 were poor responders and 418 were good responders. The best performance for the prediction task was achieved by random forest (RF), with sensitivity, specificity and area under the receiver operating characteristic curve of 0.900, 0.851 and 0.923. Ophthalmologist 1 and ophthalmologist 2 reached sensitivity of 0.775 and 0.750, and specificity of 0.716 and 0.821, respectively. The sum of hyperreflective dots was found to be the most relevant feature for prediction.

CONCLUSION

An RF classifier was constructed to predict the treatment response of anti-VEGF from OCT images of DME patients with high accuracy. The algorithm contributes to predicting treatment requirements in advance and provides an optimal individualized therapeutic regimen.

Burden of diabetic macular oedema in patients receiving antivascular endothelial growth factor therapy in South Korea: a healthcare resource use and cost analysis

OBJECTIVE

To examine healthcare resource utilisation (HRU) and direct medical costs for patients with diabetic macular oedema (DME) treated with antivascular endothelial growth factor (anti-VEGF) in Korea by comparing with those for (1) patients with diabetes mellitus (DM) without retinopathy and (2) patients with neovascular age-related macular degeneration (nAMD) treated with anti-VEGF.

DESIGN

Retrospective cohort study.

SETTING

The Korean National Health Insurance (NHI) database from 1 January 2014 to 31 December 2016.

PARTICIPANTS

We identified 1398 patients older than 30 years of age who received anti-VEGF treatment for DME in 2015 after excluding patients who had a diagnosis of nAMD in 2015 and any cancer in the preceding year.

MAIN OUTCOME MEASURES

One-year healthcare resource use and direct medical costs of patients with DME treated with anti-VEGF.

RESULTS

In total, 1398 patients with DME receiving anti-VEGF, 12 813 patients with DM without retinopathy and 12 222 patients with nAMD receiving anti-VEGF were identified. Hospital admissions and outpatient visits were highest in patients with DME, while the number of licensed anti-VEGF injections in those with DME was about half that of those with nAMD (2.1 vs 3.9 per patient per year). Mean 1-year medical costs were also higher in patients with DME (US$6723) than in those with DM without retinopathy (US$2687) and nAMD (US$4980). In a multivariable analysis with matched cohorts, DME was associated with 66% higher medical costs for comorbid diseases (adjusted OR (aOR), 1.66; 95% CI 1.45 to 1.90) and 50% lower anti-VEGF injections (aOR, 0.50; 95% CI 0.46 to 0.54) compared with nAMD.

CONCLUSIONS

The overall HRU and economic burden for DME treated with anti-VEGF were higher than for DM without retinopathy or for nAMD treated with anti-VEGF. Meanwhile, the lower number of licensed anti-VEGF injections compared with nAMD may reflect a potential lack of ophthalmological treatment for DME supported by the NHI in Korea.

Rates of Eye Care and Diabetic Eye Disease among Insured Patients with Newly Diagnosed Type 2 Diabetes

PURPOSE

To determine rates of eye examinations and diabetic eye disease in the first 5 years after diagnosis of type 2 diabetes (DM2) among continuously insured adults.

DESIGN

Retrospective, longitudinal cohort study.

PARTICIPANTS

Insured patients aged 40 years or older with newly diagnosed DM2 (n = 42 684), and control patients without diabetes matched on age, sex, and race were identified from a nationwide commercial claims database containing data from 2007 to 2015.

METHODS

All patients were tracked for 6 years: 1 year before and 5 years after the index diabetes diagnosis. Receipt of eye care for individual patients was identified using International Classification of Diseases 9th edition (ICD-9) procedure codes or Current Procedural Terminology (CPT) codes indicating an eye examination, as well as encounters indicating the patient was seen by an ophthalmologist. A diagnosis of diabetic eye disease was determined by using ICD-9 codes.

MAIN OUTCOME MEASURES

Outcome measures included annual receipt of eye care and development of diabetic eye disease, namely, diabetic retinopathy (DR). Associations between these outcomes and demographic factors were tested with multivariable logistic regression.

RESULTS

Diabetic patients received more eye examinations than controls in each year, but no more than 40.4% of diabetic patients received an examination in any given year. Patients with Medicare Advantage received fewer eye examinations at 5 years (odds ratio [OR], 0.79; P < 0.01) than those with private insurance but were less likely to develop DR (OR, 0.71; P < 0.01). Hispanic patients had higher rates of DR (OR, 1.60; P < 0.01) and received fewer eye examinations (OR, 0.75; P < 0.01) at 5 years compared with White patients. Men received fewer eye examinations (OR, 0.84; P < 0.01) and were more likely to develop DR at 5 years (OR, 1.17; P < 0.01) than women. Patients with higher education were more likely to receive an eye examination and less likely to develop DR.

CONCLUSIONS

The majority of diabetic patients do not receive adequate eye care within the 5 years after initial diabetes diagnosis despite having insurance. Efforts should be made to improve adherence to screening guidelines, especially for vulnerable populations.

Treatment patterns in diabetic macular edema in Taiwan: a retrospective chart review

Objectives

To characterize diabetic macular edema (DME) treatment patterns in Taiwan and examine their impact on health care resource utilization and visual and anatomic outcomes.

Methods

Retrospective, observational cohort study of longitudinal data from medical records of five hospital ophthalmology clinics. Patients with type 2 diabetes and DME who received ≥1 laser treatment or pharmacotherapy (intravitreal/subtenon corticosteroids and/or intravitreal anti-vascular endothelial growth factor [VEGF] agents) between January 2012 and December 2013 (index period) and attended ≥1 follow-up visit after the first treatment during that period were identified (prevalent population, N=431). In addition, a subset that received no anti-VEGFs before 2012 (anti-VEGF-naïve population, N=77) was analyzed. Outcome measures were change in DME treatment distribution between January 2009 and December 2014 and health care resource utilization over up to 3 years from the first DME treatment received in the index period (prevalent population), mean number of anti-VEGF injections and change from baseline in visual acuity and central macular thickness over 12 months (anti-VEGF-naïve population).

Results

Between 2009 and 2014, laser treatment use declined, overall use of anti-VEGFs increased, and bevacizumab use decreased proportionately as ranibizumab use increased. Patients receiving corticosteroids and anti-VEGFs in the first 6 months post-index had greater health care resource utilization than those treated with laser, corticosteroids, or anti-VEGF alone (P<0.0001, cross-cohort comparison). Among anti-VEGF-naïve patients, 69% received one to four anti-VEGF injections in the first year post-index. Overall, visual acuity improvement from baseline was minimal at 1 year (0.4 letters, observed data; 0.1 letters, last observation carried forward), and modest central macular thickness reduction (28 µm [last observation carried forward]) was detected.

Conclusion

In Taiwanese clinics, DME treatment patterns have shifted from use of laser to anti-VEGFs (with higher health care resource utilization); however, few patients receive anti-VEGF injections at the frequency reported in landmark trials, consistent with poorer visual outcomes. Effective alternative treatments with lower treatment burden should be considered.

Involvement of ciliary neurotrophic factor in early diabetic retinal neuropathy in streptozotocin-induced diabetic rats

Objective

Ciliary neurotrophic factor (CNTF) has been evaluated as a candidate therapeutic agent for diabetes and its neural complications. However, its role in diabetic retinopathy has not been fully elucidated.

Methods

This is a randomized unblinded animal experiment. Wistar rats with streptozocin (STZ)-induced diabetes were regularly injected with CNTF or vehicle control in their vitreous bodies beginning at 2 weeks after STZ injection. A total of five injections were used. In diabetic rats, the levels of CNTF and neurotrophin-3 (NT-3) were evaluated by enzyme-linked immunosorbent assays (ELISA) and real-time PCR. The abundance of tyrosine hydroxylase (TH) and β-III tubulin was detected by western blot. Transferase-mediated dUTP nick-end labeling staining (TUNEL) was used to detect cell apoptosis in the retinal tissue. The activation of caspase-3 was also measured.

Results

The protein and mRNA levels of CNTF in diabetic rat retinas were reduced compared to control rats. In addition, retinal ganglion cells (RGCs) and dopaminergic amacrine cells appeared to undergo degeneration in diabetic rat retinas, as revealed by transferase-mediated dUTP nick-end labeling staining (TUNEL). Tyrosine hydroxylase (TH) and β-III tubulin protein levels also decreased significantly. Intraocular administration of CNTF rescued RGCs and dopaminergic amacrine cells from neurodegeneration and counteracted the downregulation of β-III tubulin and TH expression, thus demonstrating its therapeutic potential.

Conclusion

Our study suggests that early diabetic retinal neuropathy involves the reduced expression of CNTF and can be ameliorated by an exogenous supply of this neurotrophin.

Diabetic retinopathy: new therapeutic perspectives based on pathogenic mechanisms

Diabetic retinopathy (DR) is the leading cause of visual impairment and preventable blindness and represents a significant socioeconomic cost for healthcare systems worldwide. In early stages of DR the only therapeutic strategy that physicians can offer is a tight control of the risk factors for DR (mainly blood glucose and blood pressure). The currently available treatments for DR are applicable only at advanced stages of the disease and are associated with significant adverse effects. Therefore, new treatments for the early stages of DR are needed. However, in early stages of DR invasive treatments such as intravitreal injections are too aggressive, and topical treatment seems to be an emerging route. In the present review, therapeutic strategies based on the main pathogenic mechanisms involved in the development of DR are reviewed. The main gap in the clinical setting is the treatment of early stages of DR and, therefore, this review emphasizes in this issue by giving an overview of potential druggable targets. By understanding of disease-specific pathogenic mechanisms, biological heterogeneity and progression patterns in early and advanced DR a more personalised approach to patient treatment will be implemented.

Type 2 diabetes in Vietnam: a cross-sectional, prevalence-based cost-of-illness study

BACKGROUND

According to the International Diabetes Federation, total global health care expenditures for diabetes tripled between 2003 and 2013 because of increases in the number of people with diabetes as well as in the average expenditures per patient. This study aims to provide accurate and timely information about the economic impacts of type 2 diabetes mellitus (T2DM) in Vietnam.

METHOD

The cost-of-illness estimates followed a prospective, prevalence-based approach from the societal perspective of T2DM with 392 selected diabetic patients who received treatment from a public hospital in Ho Chi Minh City, Vietnam, during the 2016 fiscal year.

RESULTS

In this study, the annual cost per patient estimate was US $246.10 (95% CI 228.3, 267.2) for 392 patients, which accounted for about 12% (95% CI 11, 13) of the gross domestic product per capita in 2017. That includes US $127.30, US $34.40 and US $84.40 for direct medical costs, direct nonmedical expenditures, and indirect costs, respectively. The cost of pharmaceuticals accounted for the bulk of total expenditures in our study (27.5% of total costs and 53.2% of direct medical costs). A bootstrap analysis showed that female patients had a higher cost of treatment than men at US $48.90 (95% CI 3.1, 95.0); those who received insulin and oral antidiabetics (OAD) also had a statistically significant higher cost of treatment compared to those receiving OAD, US $445.90 (95% CI 181.2, 690.6). The Gradient Boosting Regression (Ensemble method) and Lasso Regression (Generalized Linear Models) were determined to be the best models to predict the cost of T2DM (R2=65.3, mean square error [MSE]=0.94; and R2=64.75, MSE=0.96, respectively).

CONCLUSION

The findings of this study serve as a reference for policy decision making in diabetes management as well as adjustment of costs for patients in order to reduce the economic impact of the disease.

Direct medical cost associated with diabetic retinopathy severity in type 2 diabetes in Singapore

Diabetic retinopathy (DR) is a leading cause of vision-loss globally among type 2 diabetes (T2DM) patients. Information on the economic burden of DR in Singapore is limited. We aim to identify the total annual direct medical costs of DR at different stages, and to examine factors influencing the costs. Four hundreds and seventy T2DM patients who attended the Diabetes Centre in a secondary hospital in Singapore in 2011-2014 were included. Digital color fundus photographs were assessed for DR in a masked fashion. Retinopathy severity was further categorized into non-proliferative DR (NPDR), including mild, moderate and severe NPDR, and proliferative DR (PDR). Medical costs were assessed using hospital administrative data. DR was diagnosed in 172 (39.5%) patients, including 51 mild, 62 moderate and 18 severe NPDR, and 41 PDR. The median cost in DR [2012.0 (1111.2-4192.3)] was significantly higher than that in non-DR patients [1158.1 (724.1-1838.9)] (p<0.001). The corresponding costs for mild, moderate, severe NPDR and PDR were [1167.1 (895.4-2012.0)], [2212.0 (1215.5-3825.5)], [2717.5 (1444.0-6310.7)], and [3594.8.1 (1978.4-8427.7)], respectively. After adjustment, the corresponding cost ratios for mild, moderate, severe NPDR, and PDR relative to non-DR were 1.1 (p = 0.827), 1.8 (p = 0.003), 2.0 (p = 0.031) and 2.3 (p<0.001), respectively. The other factors affecting the total cost include smoking (ratio = 1.7, p = 0.019), neuropathy (ratio = 1.9, p = 0.001) and chronic kidney disease (CKD) (ratio = 1.4, p = 0.019). The presence and severity of DR was associated with increased direct medical costs in T2DM. Our results suggest that preventing progression of DR may reduce the economic burden of DR.

Cost of diabetic eye, renal and foot complications: a methodological review

INTRODUCTION

Diabetic retinopathy (DR), diabetic kidney disease (DKD) and diabetic foot ulcer (DFU) represent a public health and economic concern that may be assessed with cost-of-illness (COI) studies.

OBJECTIVES

(1) To review COI studies published between 2000 and 2015, about DR, DKD and DFU; (2) to analyse methods used.

METHODS

Disease definition, epidemiological approach, perspective, type of costs, activity data sources, cost valuation, sensitivity analysis, cost discounting and presentation of costs may be described in COI studies. Each reviewed study was assessed with a methodological grid including these nine items.

RESULTS

The five following items have been detailed in the reviewed studies: epidemiological approach (59 % of studies described it), perspective (75 %), type of costs (98 %), activity data sources (91 %) and cost valuation (59 %). The disease definition and the presentation of results were detailed in fewer studies (respectively 50 and 46 %). In contrast, sensitivity analysis was only performed in 14 % of studies and cost discounting in 7 %. Considering the studies showing an average cost per patient and per year with a societal perspective, DR cost estimates were US $2297 (range 5-67,486), DKD cost ranged from US $1095 to US $16,384, and DFU cost was US $10,604 (range 1444-85,718).

DISCUSSION

This review reinforces the need to adequately describe the method to facilitate literature comparisons and projections. It also recalls that COI studies represent complementary tools to cost-effectiveness studies to help decision makers in the allocation of economic resources for the management of DR, DKD and DFU.

Retina and Choroid of Diabetic Patients Without Observed Retinal Vascular Changes: A Longitudinal Study

PURPOSE

To identify changes in choroidal thickness (CT) and all retinal layers of diabetic patients without diabetic retinopathy (DR) after 1 year of follow-up.

DESIGN

Prospective observational cohort study.

METHODS

Overall, 125 diabetic patients without DR were included. Two visits were scheduled: the first visit (V1) and a second visit after 12 months (V2). At both visits, patients received a complete ophthalmologic evaluation that included OCT. Each retinal layer thickness was calculated for 9 ETDRS sectors, and CT was measured at 13 locations. Generalized linear mixed-effects models were used.

RESULTS

Of the 125 patients, 103 completed the study, and 9 of the 103 developed DR (8.7%). CT was significantly higher at V2 than at V1, with an average value of 10-17 μm at almost half the locations (500, 1000, and 1500 μm temporal; 500 and 1000 μm nasal; and 1000 μm superior to the fovea) (P < .001-.003). The thicknesses of the ganglion cell layer (I3 and N6 sectors), inner plexiform layer (S6 and N6 sectors), inner nuclear layer (T6 and N6 sectors), and outer plexiform layer (S6 sector), as well as the overall retinal thickness (RT) (S3, N3, I3, S6, and T6 sectors), were decreased at V2 (P < .001). Visible retinopathy was negatively associated with overall RT (central, S3, T3, I3, and N3 sectors, P = .004-.024) and the thickness of the ONL (T6 and I6 sectors, P = .007 and P = .009) and photoreceptor layer (N6 sector, P = .038). The presence of DR decreased the overall RT by 13.04-16.63 μm.

CONCLUSIONS

Diabetic patients without DR showed a thicker choroid and a thinner retina, particularly in inner layers, after 1 year of follow-up. These structural changes may correspond to the early neurodegenerative phase of DR.

Comorbidity and health care visit burden in working-age commercially insured patients with diabetic macular edema

PURPOSE

To examine the comorbidity profile and update estimates of health care resource utilization for commercially insured, working-age adults with diabetic macular edema (DME) relative to a matched comparison group of diabetic adults without DME. Additional comparisons were made in the subgroup of pseudophakic patients.

PATIENTS AND METHODS

A retrospective matched-cohort study of commercially insured diabetic adults aged 18-63 years was conducted using medical and outpatient pharmacy claims (July 1, 2008-June 30, 2013). Outcomes included diabetes-related and ocular comorbidities and health care resource utilization (any health care visit days, outpatient visit days, inpatient visit days, emergency room visits, eye care-related visit days, unique medications) in the 12-month post-index period.

RESULTS

All diabetes-related and ocular comorbidities were significantly more prevalent in DME cases versus non-DME controls (P<0.05). A significantly greater proportion of DME cases utilized eye care-related visits compared with non-DME controls (P<0.001). DME cases had almost twice the mean number of total health care visit days compared to non-DME controls (28.6 vs 16.9 days, P<0.001), with a minority of visit days being eye care-related (mean 5.1 vs 1.5 days, P<0.001). Similar trends were observed in pseudophakic cohorts.

CONCLUSION

This working-age DME population experienced a mean of 29 health care visit days per year. Eye care-related visit days were a minority of the overall visit burden (mean 5 days) emphasizing the trade-offs DME patients face between managing DME and their overall diabetic disease. Insights into the complex comorbidity profile and health care needs of diabetic patients with DME will better inform treatment decisions and help optimize disease management.

Direct cost of pars plana vitrectomy for the treatment of macular hole, epiretinal membrane and vitreomacular traction: a bottom-up approach

PURPOSE

The direct cost to the National Health Service (NHS) in England of pars plana vitrectomy (PPV) is unknown since a bottom-up costing exercise has not been undertaken. Healthcare resource group (HRG) costing relies on a top-down approach. We aimed to quantify the direct cost of intermediate complexity PPV.

METHODS

Five NHS vitreoretinal units prospectively recorded all consumables, equipment and staff salaries during PPV undertaken for vitreomacular traction, epiretinal membrane and macular hole. Out-of-surgery costs between admission and discharge were estimated using a representative accounting method.

RESULTS

The average patient time in theatre for 57 PPVs was 72 min. The average in-surgery cost for staff was £297, consumables £619, and equipment £82 (total £997). The average out-of-surgery costs were £260, including nursing and medical staff, other consumables, eye drops and hospitalisation. The total cost was therefore £1634, including 30 % overheads. This cost estimate was an under-estimate because it did not include out-of-theatre consumables or equipment. The average reimbursed HRG tariff was £1701.

CONCLUSIONS

The cost of undertaking PPV of intermediate complexity is likely to be higher than the reimbursed tariff, except for hospitals with high throughput, where amortisation costs benefit from economies of scale. Although this research was set in England, the methodology may provide a useful template for other countries.

The Effects of Diagnostic Definitions in Claims Data on Healthcare Cost Estimates: Evidence from a Large-Scale Panel Data Analysis of Diabetes Care in Japan

BACKGROUND

Inaccurate estimates of diabetes-related healthcare costs can undermine the efficiency of resource allocation for diabetes care. The quantification of these costs using claims data may be affected by the method for defining diagnoses.

OBJECTIVES

The aims were to use panel data analysis to estimate diabetes-related healthcare costs and to comparatively evaluate the effects of diagnostic definitions on cost estimates.

RESEARCH DESIGN

Monthly panel data analysis of Japanese claims data.

SUBJECTS

The study included a maximum of 141,673 patients with type 2 diabetes who received treatment between 2005 and 2013.

MEASURES

Additional healthcare costs associated with diabetes and diabetes-related complications were estimated for various diagnostic definition methods using fixed-effects panel data regression models.

RESULTS

The average follow-up period per patient ranged from 49.4 to 52.3 months. The number of patients identified as having type 2 diabetes varied widely among the diagnostic definition methods, ranging from 14,743 patients to 141,673 patients. The fixed-effects models showed that the additional costs per patient per month associated with diabetes ranged from US$180 [95 % confidence interval (CI) 178-181] to US$223 (95 % CI 221-224). When the diagnostic definition excluded rule-out diagnoses, the diabetes-related complications associated with higher additional healthcare costs were ischemic heart disease with surgery (US$13,595; 95 % CI 13,568-13,622), neuropathy/extremity disease with surgery (US$4594; 95 % CI 3979-5208), and diabetic nephropathy with dialysis (US$3689; 95 % CI 3667-3711).

CONCLUSIONS

Diabetes-related healthcare costs are sensitive to diagnostic definition methods. Determining appropriate diagnostic definitions can further advance healthcare cost research for diabetes and its applications in healthcare policies.

Impact of injection therapy on retinal patients with diabetic macular edema or retinal vein occlusion

Purpose

An important factor in the choice of therapy is the impact it has on the patient’s quality of life. This survey aimed to understand treatment burden, treatment-related anxiety and worry, and practical issues such as appointment attendance and work absence in patients receiving injection therapy for diabetic macular edema (DME) or retinal vein occlusion (RVO).

Patients and methods

A European sample of 131 retinal patients completed a detailed questionnaire to elucidate the impact of injection therapy on individuals with DME or RVO.

Results

RVO and DME greatly impact a patient’s quality of life. An intensive injection regimen and the requirements for multiple hospital visits place a large practical burden on the patient. Each intravitreal injection appointment (including travel time) was reported to take an average of 4.5 hours, with a total appointment burden over 6 months of 13.5 hours and 20 hours for RVO and DME patients, respectively. This creates a significant burden on patient time and may make appointment attendance difficult. Indeed, 53% of working patients needed to take at least 1 day off work per appointment and 71% of patients required a carer’s assistance at the time of the injection appointment, ~6.3 hours per injection. In addition to practical issues, three-quarters of patients reported experiencing anxiety about their most recent injection treatment, with 54% of patients reporting that they were anxious for at least 2 days prior to the injection. Patients’ most desired improvement to their treatment regimen was to have fewer injections and to require fewer appointments, to achieve the same visual results.

Conclusion

Patients’ quality of life is clearly very affected by having to manage an intensive intravitreal injection regimen, with a considerable treatment burden having a large negative effect. Reducing the appointment burden to achieve the same visual outcomes and the provision of additional support for patients to attend appointments would greatly benefit those receiving intravitreal injection therapies for DME and RVO.

Cost-utility of ranibizumab versus aflibercept for treating Greek patients with visual impairment due to diabetic macular edema

Background

To conduct a cost-utility analysis of ranibizumab versus aflibercept for the treatment of patients with visual impairment due to diabetic macular edema (DME) in the Greek setting.

Methods

A Markov model was adapted to compare the use of ranibizumab 0.5 mg (pro re nata-PRN and treat and extend-T&E) to aflibercept 2 mg (every 8 weeks after five initial doses) in DME. Patients transitioned at a 3-month cycle among nine specified health states (including death) over a lifetime horizon. Transition probabilities, utilities, as well as DME-related mortality were extracted from relevant clinical trials, a network meta-analysis and other published studies. The analysis was conducted from payer perspective and as such only costs reimbursed by the payer were considered (year 2014). The incremental cost per quality-adjusted life year (QALY) gained and the net monetary benefit was the main outcome measures.

Results

Τhe use of PRN and T&E ranibizumab regimens were shown to be cost saving comparing to aflibercept (by €2824 and €22, respectively), and more beneficial in terms of QALYs gained (+0.05) and time without visual impairment (0.031 and 0.034 years), thereby dominating aflibercept. Moreover, ranibizumab used as PRN or T&E resulted in a net monetary benefit of €3984 and €1278, respectively.

Conclusions

Both PRN and T&E ranibizumab regimens were more beneficial and less costly compared to aflibercept for the management of DME. Hence, ranibizumab seems to be a dominant option for the treatment of visual impairment due to DME in the Greek setting.

Electronic supplementary material

The online version of this article (doi:10.1186/s12962-016-0056-1) contains supplementary material, which is available to authorized users.

Analysis of costs associated with the management and morbidity of diabetic macular oedema and macular oedema secondary to retinal vein occlusion

OBJECTIVE

To analyse the disease burden in patients with diabetic macular oedema (DMO) or with retinal vein occlusion macular oedema (RVOMO) from a societal perspective.

METHODS

Observational, cross-sectional, multicentre study conducted on patients >18 years old diagnosed with uni- or bilateral DMO or unilateral RVOMO. Data on the use of health resources from diagnosis was collected, and the impact of disease on work life was assessed. Costs were annualised (euros, January 2014). Differences were contrasted using Chi-squared test (or Fisher Exact test), Mann Whitney-U test or Kruskal-Wallis test (Dunn contrast).

RESULTS

A total of 448 patients were included (DMO 255; RVOMO 193). There were significant differences in costs of diagnosis: RVOMO €1856, bilateral DMO €1661, and unilateral DMO €1401 (P<.001) and the aggregate medical costs: RVOMO €4639, bilateral DMO 6275€ and unilateral DMO 6269€ (P<.001). Cost by permanent time off work was higher in bilateral DMO €11712, than in unilateral DMO €4284€, and than in RVOMO €1052 (P<.05). Linear regression analysis showed that variables associated with direct health costs were: Diagnosis (bilateral DMO was associated with higher cost), as well as number of days in hospital, number of visits, time of observation, and number of days of time off work.

CONCLUSIONS

Patients with bilateral DMO are associated with a higher direct health cost, as well as a higher indirect cost by impact of the disease on work life.

Trends in health care expenditure in U.S. adults with diabetes: 2002-2011

OBJECTIVE

Direct medical cost of diabetes in the U.S. has been estimated to be 2.3 times higher relative to individuals without diabetes. This study examines trends in health care expenditures by expenditure category in U.S. adults with diabetes between 2002 and 2011.

RESEARCH DESIGN AND METHODS

We analyzed 10 years of data representing a weighted population of 189,013,514 U.S. adults aged ≥18 years from the Medical Expenditure Panel Survey. We used a novel two-part model to estimate adjusted mean and incremental medical expenditures by diabetes status, while adjusting for demographics, comorbidities, and time.

RESULTS

Relative to individuals without diabetes ($5,058 [95% CI 4,949-5,166]), individuals with diabetes ($12,180 [11,775-12,586]) had more than double the unadjusted mean direct expenditures over the 10-year period. After adjustment for confounders, individuals with diabetes had $2,558 (2,266-2,849) significantly higher direct incremental expenditures compared with those without diabetes. For individuals with diabetes, inpatient expenditures rose initially from $4,014 in 2002/2003 to $4,183 in 2004/2005 and then decreased continuously to $3,443 in 2010/2011, while rising steadily for individuals without diabetes. The estimated unadjusted total direct expenditures for individuals with diabetes were $218.6 billion/year and adjusted total incremental expenditures were approximately $46 billion/year.

CONCLUSIONS

Our findings show that compared with individuals without diabetes, individuals with diabetes had significantly higher health expenditures from 2002 to 2011 and the bulk of the expenditures came from hospital inpatient and prescription expenditures.

Is fenofibrate a reasonable treatment for diabetic microvascular disease?

Type 2 diabetes is a pandemic disease, and its prevalence is increasing mainly due to an increase in obesity and life expectancy. Diabetic complications and their comorbidities constitute the most important economic cost of the disease and represent a significant economic burden for the healthcare systems of developed countries. Despite improving standards of care, people with diabetes remain at risk of the development and progression of microvascular diabetic complications. Therefore, the identification of novel therapeutic approaches is necessary. The aim of this article is to provide an overview of the clinical benefits of fenofibrate on microvascular diabetic complications, with special emphasis on diabetic retinopathy. In addition, the potential mechanisms of action will be briefly discussed.

Comparative effectiveness of anti-VEGF agents for diabetic macular edema

OBJECTIVES

The aim of this study was to evaluate the comparative effectiveness of anti-vascular endothelial growth factor therapy in the treatment of diabetic macular edema (DME).

METHODS

Searches focused on reports concerning treatment of DME with aflibercept, bevacizumab, pegaptanib, or ranibizumab published between January 2000 and June 30, 2012, with comparisons to laser photocoagulation, sham injection, or other control (e.g., triamcinolone). Effectiveness was based on best-corrected visual acuity (BCVA), in terms of letters gained. Direct meta-analyses were conducted on BCVA for each anti-vascular endothelial growth factor (VEGF) agent; indirect comparisons also were performed for each anti-VEGF pair.

RESULTS

A total of fifteen randomized controlled trials (eleven fair- or good-quality) and eight observational studies were included. No direct comparative studies were identified. Improvement in visual acuity versus control was seen with all agents (range: 4-9 letters); outcomes were consistent across multiple timepoints. Meta-analyses showed no statistically significant and/or consistent differences between agents in BCVA changes or the percentage of patients gaining more than ten letters. No discernible differences in the potential harms of anti-VEGFs, including ocular events, MI, stroke, and other cardiovascular events, as well as death, were noted between aflibercept, pegaptanib, and ranibizumab. Data on harms for bevacizumab were underreported.

CONCLUSIONS

All anti-VEGF agents are effective in improving visual acuity in comparison to laser photocoagulation. Evidence is insufficient to distinguish the performance of any single anti-VEGF agent over others. The safety of bevacizumab remains the greatest element of uncertainty.

Non-traditional systemic treatments for diabetic retinopathy: an evidence-based review

The rapid escalation in the global prevalence diabetes, with more than 30% being afflicted with diabetic retinopathy (DR), means it is likely that associated vision-threatening conditions will also rise substantially. This means that new therapeutic approaches need to be found that go beyond the current standards of diabetic care, and which are effective in the early stages of the disease. In recent decades several new pharmacological agents have been investigated for their effectiveness in preventing the appearance and progression of DR or in reversing DR; some with limited success while others appear promising. This up-to-date critical review of non-traditional systemic treatments for DR is based on the published evidence in MEDLINE spanning 1980-December 2014. It discusses a number of therapeutic options, paying particular attention to the mechanisms of action and the clinical evidence for the use of renin-angiotensin system blockade, fenofibrate and calcium dobesilate monohydrate in DR.

United States comparative costs and absenteeism of diabetic ophthalmic conditions

OBJECTIVE

This retrospective cohort study examined the impact of diabetic macular edema (DME), diabetic retinopathy (DR), or diabetes on annual health benefit costs and absenteeism in US employees.

METHODS

Claims data from 2001 to 2012 was extracted from the Human Capital Management Services Group Research Reference Database on annual direct/indirect health benefit costs and absences for employees aged ≥ 18 years. Employees with DME, DR, or diabetes were identified by International Classification of Diseases, Ninth Revision, Clinical Modification codes. Employees were divided into two groups, drivers or nondrivers, and examined in separate analyses. For drivers and nondrivers, the DME, DR, and diabetes cohorts were compared with their respective control groups (without diabetes). Two-part regression models controlled for demographics and job-related characteristics.

RESULTS

A total of 39,702 driver and 426,549 nondriver employees were identified as having ≥ 1 year's continuous health plan enrollment. Direct medical costs for drivers with DME, DR, or diabetes were $6470, $8021, and $5102, respectively (>2.8 times higher and statistically significant compared with driver controls). Nondrivers with DME and DR incurred significantly higher sick leave and short-term disability costs compared with the nondrivers with diabetes and nondriver controls. In drivers with DME, the majority of days of absence were for short- and long-term disability (12.41 and 11.43 days, respectively). In drivers with DR, the majority of days of absence were for short-term disability (10.70 days). In nondrivers with DME and nondrivers with DR, the majority of days of absence were for sick leave (5.74 and 4.93 days, respectively) and short-term disability (5.08 and 4.93 days, respectively).

CONCLUSION

DME and DR are associated with substantial direct medical cost and absenteeism in this real-world sample of medically insured employees. This research highlights the negative impact of DME and DR on annual costs and absenteeism and may assist employers in assessing the impact of these conditions on employees.

The economic burden of elevated blood glucose levels in 2012: diagnosed and undiagnosed diabetes, gestational diabetes mellitus, and prediabetes

OBJECTIVE

To update estimates of the economic burden of undiagnosed diabetes, prediabetes, and gestational diabetes mellitus in 2012 in the U.S. and to present state-level estimates. Combined with published estimates for diagnosed diabetes, these statistics provide a detailed picture of the economic costs associated with elevated glucose levels.

RESEARCH DESIGN AND METHODS

This study estimated health care use and medical expenditures in excess of expected levels occurring in the absence of diabetes or prediabetes. Data sources that were analyzed include Optum medical claims for ∼4.9 million commercially insured patients who were continuously enrolled from 2010 to 2012, Medicare Standard Analytical Files containing medical claims for ∼2.6 million Medicare patients in 2011, and the 2010 Nationwide Inpatient Sample containing ∼7.8 million hospital discharge records. The indirect economic burden includes reduced labor force participation, missed workdays, and reduced productivity. State-level estimates reflect geographic variation in prevalence, risk factors, and prices.

RESULTS

The economic burden associated with diagnosed diabetes (all ages) and undiagnosed diabetes, gestational diabetes, and prediabetes (adults) exceeded $322 billion in 2012, consisting of $244 billion in excess medical costs and $78 billion in reduced productivity. Combined, this amounts to an economic burden exceeding $1,000 for each American in 2012. This national estimate is 48% higher than the $218 billion estimate for 2007. The burden per case averaged $10,970 for diagnosed diabetes, $5,800 for gestational diabetes, $4,030 for undiagnosed diabetes, and $510 for prediabetes.

CONCLUSIONS

These statistics underscore the importance of finding ways to reduce the burden of prediabetes and diabetes through prevention and treatment.

Anti-VEGF therapy for diabetic macular edema

Vascular endothelial growth factor (VEGF) plays a pivotal role in the development of diabetic macular edema (DME), the leading cause of vision loss among working-aged individuals. A decade of clinical trials demonstrated that drugs that bind soluble VEGF restore the integrity of the blood-retinal barrier, resolve macular edema, and improve vision in most patients with DME. Four drugs (pegaptanib, ranibizumab, bevacizumab, and aflibercept) effectively treat DME when administered by intravitreal injections. Only ranibizumab has received U.S. Food and Drug Administration (FDA) approval for DME, but bevacizumab is commonly used off-label, and an FDA application for aflibercept is pending. Effective treatment requires repeated injections, although recent data suggest that the treatment burden diminishes after 1 year. Intravitreal therapy is generally safe, although the incidence of systemic thromboembolic events varies among trials.

Somatostatin and diabetic retinopathy: current concepts and new therapeutic perspectives

Somatostatin (SST) is abundantly produced by the human retina, and the main source is the retinal pigment epithelium (RPE). SST exerts relevant functions in the retina (neuromodulation, angiostatic, and anti-permeability actions) by interacting with SST receptors (SSTR) that are also expressed in the retina. In the diabetic retina, a downregulation of SST production does exist. In this article, we give an overview of the mechanisms by which this deficit of SST participates in the main pathogenic mechanisms involved in diabetic retinopathy (DR): neurodegeneration, neovascularization, and vascular leakage. In view of the relevant SST functions in the retina and the reduction of SST production in the diabetic eye, SST replacement has been proposed as a new target for treatment of DR. This could be implemented by intravitreous injections of SST analogs or gene therapy, but this is an aggressive route for the early stages of DR. Since topical administration of SST has been effective in preventing retinal neurodegeneration in STZ-induced diabetic rats, it seems reasonable to test this new approach in humans. In this regard, the results of the ongoing clinical trial EUROCONDOR will provide useful information. In conclusion, SST is a natural neuroprotective and antiangiogenic factor synthesized by the retina which is downregulated in the diabetic eye and, therefore, its replacement seems a rational approach for treating DR. However, clinical trials will be needed to establish the exact position of targeting SST in the treatment of this disabling complication of diabetes.

Costs and Quality of Life in Diabetic Macular Edema: Canadian Burden of Diabetic Macular Edema Observational Study (C-REALITY)

Purpose. To characterize the economic and quality of life burden of diabetic macular edema (DME) in Canadian patients. Patients and Methods. 145 patients with DME were followed for 6 months with monthly telephone interviews and medical chart reviews at months 0, 3, and 6. Visual acuity in the worst-seeing eye was assessed at months 0 and 6. DME-related healthcare costs were determined over 6 months, and vision-related (National Eye Institute Visual Functioning Questionnaire) and generic (EQ-5D) quality of life was assessed at months 0, 3, and 6. Results. Mean age of patients was 63.7 years: 52% were male and 72% had bilateral DME. At baseline, visual acuity was categorized as normal/mild loss for 63.4% of patients, moderate loss for 10.4%, and severe loss/nearly blind for 26.2%. Mean 6-month DME-related costs/patient were as follows: all patients (n = 135), $2,092; normal/mild loss (n = 88), $1,776; moderate loss (n = 13), $1,845; and severe loss/nearly blind (n = 34), $3,007. Composite scores for vision-related quality of life declined with increasing visual acuity loss; generic quality of life scores were highest for moderate loss and lowest for severe loss/nearly blind. Conclusions. DME-related costs in the Canadian healthcare system are substantial. Costs increased and vision-related quality of life declined with increasing visual acuity severity.

Neurodegeneration in the diabetic eye: new insights and therapeutic perspectives

Diabetic retinopathy (DR), one of the leading causes of preventable blindness, has been considered a microcirculatory disease of the retina. However, there is emerging evidence to suggest that retinal neurodegeneration is an early event in the pathogenesis of DR, which participates in the development of microvascular abnormalities. Therefore, the study of the underlying mechanisms leading to neurodegeneration and the identification of the mediators in the crosstalk between neurodegeneration and microangiopathy will be essential for the development of new therapeutic strategies. In this review, an updated discussion of the mechanisms involved in neurodegeneration, as well as the link between neurodegeneration and microangiopathy, is presented. Finally, the therapeutic implications and new perspectives based on identifying those patients with retinal neurodegeneration are given.

Economic costs of diabetes in the U.S. in 2012

OBJECTIVE

This study updates previous estimates of the economic burden of diagnosed diabetes and quantifies the increased health resource use and lost productivity associated with diabetes in 2012.

RESEARCH DESIGN AND METHODS

The study uses a prevalence-based approach that combines the demographics of the U.S. population in 2012 with diabetes prevalence, epidemiological data, health care cost, and economic data into a Cost of Diabetes Model. Health resource use and associated medical costs are analyzed by age, sex, race/ethnicity, insurance coverage, medical condition, and health service category. Data sources include national surveys, Medicare standard analytical files, and one of the largest claims databases for the commercially insured population in the U.S.

RESULTS

The total estimated cost of diagnosed diabetes in 2012 is $245 billion, including $176 billion in direct medical costs and $69 billion in reduced productivity. The largest components of medical expenditures are hospital inpatient care (43% of the total medical cost), prescription medications to treat the complications of diabetes (18%), antidiabetic agents and diabetes supplies (12%), physician office visits (9%), and nursing/residential facility stays (8%). People with diagnosed diabetes incur average medical expenditures of about $13,700 per year, of which about $7,900 is attributed to diabetes. People with diagnosed diabetes, on average, have medical expenditures approximately 2.3 times higher than what expenditures would be in the absence of diabetes. For the cost categories analyzed, care for people with diagnosed diabetes accounts for more than 1 in 5 health care dollars in the U.S., and more than half of that expenditure is directly attributable to diabetes. Indirect costs include increased absenteeism ($5 billion) and reduced productivity while at work ($20.8 billion) for the employed population, reduced productivity for those not in the labor force ($2.7 billion), inability to work as a result of disease-related disability ($21.6 billion), and lost productive capacity due to early mortality ($18.5 billion).

CONCLUSIONS

The estimated total economic cost of diagnosed diabetes in 2012 is $245 billion, a 41% increase from our previous estimate of $174 billion (in 2007 dollars). This estimate highlights the substantial burden that diabetes imposes on society. Additional components of societal burden omitted from our study include intangibles from pain and suffering, resources from care provided by nonpaid caregivers, and the burden associated with undiagnosed diabetes.

Molecular Implications of the PPARs in the Diabetic Eye

Diabetic retinopathy (DR) remains as the leading cause of blindness among working age individuals in developed countries. Current treatments for DR (laser photocoagulation, intravitreal corticosteroids, intravitreal anti-VEGF agents, and vitreoretinal surgery) are applicable only at advanced stages of the disease and are associated with significant adverse effects. Therefore, new pharmacological treatments for the early stages of the disease are needed. Emerging evidence indicates that peroxisome proliferator-activator receptors (PPARs) agonists (in particular PPARα) are useful for the treatment of DR. However, the underlying molecular mechanisms are far from being elucidated. This paper mainly focuses on PPARs expression in the diabetic eye, its molecular implications, and the effect of PPAR agonists as a new approach for the treatment of DR. The availability of this new strategy will not only be beneficial in treating DR but may also result in a shift towards treating earlier stages of diabetic retinopathy, thus easing the burden of this devastating disease (Cheung et al. (2010)).

Duloxetine use in chronic low back pain: treatment patterns and costs

BACKGROUND

Little is known about the real-world treatment patterns and costs of patients with chronic low back pain (CLBP) who are treated with duloxetine compared with those receiving other non-surgical treatments.

OBJECTIVE

Our objective was to compare the real-world treatment patterns and costs between patients with CLBP who initiated duloxetine and matched controls who initiated another non-surgical treatment.

METHODS

The study sample was selected from a US privately insured claims database (2004-8). Selected patients were aged 18-64 years, and had a low back pain (LBP) diagnosis (per Healthcare Effectiveness Data and Information Set [HEDIS] specifications) with a subsequent CLBP-qualifying diagnosis recorded ≥90 days after the initial LBP diagnosis. Duloxetine-treated patients had ≥1 duloxetine prescription within 6 months after CLBP diagnosis, no prior duloxetine claim, and continuous eligibility ≥12 months before first LBP diagnosis and ≥6 months after index duloxetine prescription (study period). Because duloxetine patients had higher rates of co-morbidities, 553 duloxetine-treated patients were matched to 553 control patients who initiated another non-surgical LBP treatment based on propensity score and time from first LBP diagnosis to treatment initiation. A subset (n = 103 each) of matched employees with disability data was also analysed to assess work loss. Main outcomes measures included study period treatment rates and direct (medical and drug) costs from a third-party payer perspective and employee indirect (work-loss) costs. McNemar tests were used to compare LBP treatment rates. Bias-corrected bootstrapping t-tests were used to compare costs.

RESULTS

After matching, the two groups had balanced baseline characteristics including demographics, LBP diagnostic categories, co-morbidity profiles, resource use, treatment patterns and mean direct costs. During the 6-month study period, matched duloxetine-treated patients had significantly lower rates of other pharmacological therapy (e.g. 56.2% vs 64.9% narcotic opioids, p = 0.0024; 34.9% vs 49.5% NSAIDs, p < 0.0001) and non-invasive therapy (28.8% vs 38.5% chiropractic therapy, p = 0.0007; 25.5% vs 35.4% physical therapy, p = 0.0004; 17.5% vs 28.4% exercise therapy, p < 0.0001) than controls. Duloxetine-treated patients versus controls had similar back surgery rates (2.2% vs 3.8%; p = 0.1127) and similar direct costs ($US7658 vs $US7439; p = 0.8119). Among CLBP employees, duloxetine-treated employees versus controls had lower rates of other non-surgical therapy, similar back surgery rates (0.0% vs 3.9%; p = 0.1250), lower total direct and indirect costs ($US5227 vs $US7299; p = 0.0418), and similar indirect costs ($US1806 vs $US2664; p = 0.0528).

CONCLUSIONS

Duloxetine treatment in CLBP patients/employees versus other non-surgical treatment was associated with reduced rates of non-surgical therapies and similar back surgery rates, without increased costs.

Burden of illness of diabetic macular edema: literature review

OBJECTIVE

To provide an overview of the literature on the burden of diabetic macular edema (DME) in the United States and selected European countries.

RESEARCH DESIGN AND METHODS

Computerized searches of English-language literature were conducted in PubMed/MEDLINE (1980-2009). The searches were supplemented with electronic and manual searches of relevant society/association proceedings and bibliographies of electronically identified sources. Abstracts were reviewed for relevance to any of the following topics: epidemiology, including prevalence and incidence; health outcomes; resource use and treatment patterns; and economic and humanistic burden associated with DME. Relevant full text articles were retrieved and major findings were synthesized and compared within and across countries.

RESULTS

A total of 400 citations were included in the initial review. After abstract screening, 47 articles were deemed pertinent and summarized in this review. The prevalence of DME among diabetic patients ranged from 0.85% to 12.3% across the countries studied. The prevalence and incidence of DME vary depending on type of diabetes (1 vs. 2), insulin- vs. non-insulin-dependence, and duration of disease (years since diagnosis). Although literature findings are limited and indicate a need for further investigation, a synthesis of the available results indicates that DME has a negative impact on patients' health-related quality of life. In addition, patients with DME consume significantly more healthcare resources and incur higher costs compared to diabetic patients without retinal complications.

CONCLUSIONS

There remains a need for consistent data capture and assessment within and between countries included in this analysis. Despite the limited evidence, DME appears to be a costly disease that has a negative impact on patients' quality of life.

Direct costs associated with initiating NPH insulin versus glargine in patients with type 2 diabetes: a retrospective database analysis

AIMS

To compare total costs and risk of hypoglycemia in patients with type 2 diabetes (T2D) initiated on NPH insulin versus glargine in a real-world setting.

METHODS

This study used claims data (10/2001 to 06/2005) from a privately insured U.S. population of adult T2D patients who were initiated on NPH or glargine following a 6-month insulin-free period. A sample of 1698 glargine-treated and 400 NPH-treated patients met the inclusion criteria. Total and diabetes-related costs (inflation-adjusted to 2006) were calculated for 6-month pre- and post-index periods and compared between 400 patient pairs matched by a propensity score method.

RESULTS

In the post-index 6-month period, glargine patients incurred higher diabetes-related drug costs than NPH patients ($785 versus $632, p<0.0001) but there were no significant differences in diabetes-related medical or total costs, or all other total cost categories. Compared to the pre-index period, glargine patient costs declined by $2420 (p=0.058) whereas NPH patient costs declined by $4200 (p=0.046), with no statistically significant group differences (p=0.469). Among patients with hypoglycemia-related claims (0.75% in both groups), mean hypoglycemia-related costs were $85 and $202 for NPH and glargine patients, respectively (p=0.564).

CONCLUSION

Initiation of either NPH or glargine was associated with major cost reductions and infrequent hypoglycemia-related claims.

Economic burden of epilepsy among the privately insured in the US

BACKGROUND

The direct cost burden of epilepsy in the US from a third-party payer perspective has not been evaluated. Furthermore, no study has quantified the indirect (work-loss) cost burden of epilepsy from an employer perspective in the US.

OBJECTIVE

To assess the annual direct costs for privately insured US patients diagnosed with epilepsy, and indirect costs for a subset of employees from an employer perspective.

METHODS

A retrospective analysis of a claims database for the privately insured, including employee disability claims from 1999 through 2005 and comprising 17 US companies, was conducted. A total of 4323 patients aged 16-64 years (including 1886 employees) with at least one epilepsy diagnosis (International Classification of Diseases, 9th edition, Clinical Modification [ICD-9-CM] code 345.x) over the period 1999-2004 were included. The control group was a demographically matched cohort of randomly chosen beneficiaries without an epilepsy diagnosis. All had continuous health coverage during 2004 (baseline) and 2005 (study period). Main outcome measures included annual direct (medical and pharmaceutical) costs and, for employees, indirect (disability and medically related absenteeism) and total costs for the study period. Wilcoxon rank-sum tests were used for univariate comparisons of annual direct costs, indirect costs (costs for the subset of employees with these data), and total (direct and indirect) costs during the study period. Two-part multivariate models that adjusted for patient characteristics were also used to compare costs between the study and control groups.

RESULTS

Patients with epilepsy were an average age of 43 years and 57% were female. They had more co-morbidities than controls. On average, direct annual costs were significantly higher per patient with epilepsy than per control ($US10 258 vs $US3862, respectively; p < 0.0001) [year 2005 values], with an annual per-patient difference of $US6396. Epilepsy-related costs ($US2057) accounted for 20% of direct costs for patients with epilepsy. Annual indirect costs were significantly higher for employees with epilepsy than for employed controls ($US3192 vs $US1242, respectively; p < 0.0001), with a difference of $US1950. Total direct plus indirect costs for employees with epilepsy were also higher than those for employed controls ($US13 595 vs $US5338, respectively; p < 0.0001), with a difference of $US8257.

CONCLUSIONS

Epilepsy was associated with significant economic burden. The excess direct costs in patients with epilepsy are underestimated when only epilepsy-related costs are considered.