Heiner Claessen

The Incidence of End-Stage Renal Disease in the Diabetic (Compared to the Non-Diabetic) Population: A Systematic Review.

End-stage renal disease (ESRD) in diabetes is a life threatening complication resulting in a poor prognosis for patients as well as high medical costs. The aims of this systematic review were (1) to evaluate the incidence of ESRD due to all causes and due to diabetic nephropathy in the diabetic population and differences between incidences of ESRD with respect to sex, ethnicity, age and regions, (2) to compare incidence rates in the diabetic and non-diabetic population, and (3) to investigate time trends. The systematic review was conducted according to the PRISMA group guidelines by performing systematic literature searches in the biomedical databases until January 3rd 2015; thirty-two studies were included. Among patients with incident type 1 diabetes the 30-year cumulative incidence ranged from 3.3% to 7.8%. Among patients with prevalent diabetes, incidence rates of ESRD due to all causes ranged from 132.0 to 167.0 per 100,000 person-years, whereas incidence rates of ESRD due to diabetic nephropathy varied from 38.4 to 804.0 per 100,000 person-years. The incidence of ESRD in the diabetic population was higher compared to the non-diabetic population, and relative risks varied from 6.2 in the white population to 62.0 among Native Americans. The results regarding time trends were inconsistent. The review conducted demonstrates the considerable variation of incidences of ESRD among the diabetic population. Consistent findings included an excess risk when comparing the diabetic to the non-diabetic population and ethnic differences. We recommend that newly designed studies should use standardized methods for the determination of ESRD and population at risk.

Time-Dependent Impact of Diabetes on Mortality in Patients With Stroke Survival up to 5 years in a health insurance population cohort in Germany

OBJECTIVE To estimate the impact of diabetes on mortality in patients after first stroke event. RESEARCH DESIGN AND METHODS Using claims data from a nationwide statutory health insurance fund (Gmünder ErsatzKasse), we assessed all deaths in a cohort of 5,757 patients with a first stroke between 2005 and 2007 (69.3% male, mean age 68.1 years, 32.2% with diabetes) up to 2009. By use of Cox regression, we estimated time-dependent hazard ratios (HRs) to compare patients with and without diabetes stratified by sex. RESULTS The cumulative 5-year mortality was 40.0 and 54.2% in diabetic men and women, and 32.3 and 38.1% in their nondiabetic counterparts, respectively. In males, mortality was significantly lower in diabetic compared with nondiabetic patients in the first 30 days (multiple-adjusted HR 0.67 [95% CI 0.53–0.84]). After approximately a quarter of a year, the diabetes risk increased, yielding crossed survival curves. Later on, mortality risk tended to be similar in diabetic and nondiabetic men (1–2 years: 1.42 [1.09–1.85]; 3–5 years: 1.00 [0.67–1.41]; time dependency of diabetes, P = 0.008). In women, the pattern was similar; however, time dependency was not statistically significant (P = 0.89). Increasing age, hemorrhagic stroke, renal failure (only in men), levels of care dependency, and number of prescribed medications were significantly associated with mortality. CONCLUSIONS We found a time-dependent mortality risk of diabetes after first stroke in men. Possible explanations may be type of stroke or earlier and more intensive treatment of risk factors in diabetic patients.

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

AIMS To compare direct medical costs 1 year before up to 3 years after first major lower extremity amputation (LEA) between patients with and without diabetes. METHODS We used health insurance claims data and included patients with a first major LEA between 2005 and 2009. Costs for hospitalization, rehabilitation, outpatient care, outpatient drug prescriptions, non-physician services, durable medical equipment and long-term care were assessed. We estimated cost ratios (CR) for diabetes status using generalized linear models adjusted for age, sex, amputation level, care dependency as well as observation time and mortality within the corresponding period and costs before LEA. RESULTS We included 444 patients with first major LEA (58.3% had diabetes), 71.8% were male and the average age was 69.1 years. Total mean costs for 1 year before LEA were higher in patients with diabetes (24,504 vs. 18,961 Euros), which was also confirmed by the multivariate analysis (CR: 1.27; 95% CI: 1.06-1.52). Costs up to 24 weeks after LEA were virtually the same in both groups (36,686 vs. 35,858 Euros), but thereafter differences increase again with higher costs for diabetics. Costs for 3 years after LEA were 115,676 vs. 92,862 Euros, respectively (CR: 1.26; 95% CI: 1.12-1.42). Hospitalizations accounted for more than 50% of total costs irrespective of diabetes status and period. CONCLUSIONS Costs up to 24 weeks after first major LEA are mainly driven by the amputation itself irrespective of diabetes. Thereafter, costs for diabetic patients were higher again, which underlines the importance of studying long-term costs.

Drug Costs in Prediabetes and Undetected Diabetes Compared With Diagnosed Diabetes and Normal Glucose Tolerance: Results From the Population-Based KORA Survey in Germany

Undetected diabetes and prediabetes are common (1–3). In decision analytic models of diabetes prevention and screening in particular, the differentiation in costs of detected, undetected, and prediabetic cases are important (4). To the best of our knowledge, no study has determined costs using population-based data with oral glucose tolerance test (OGTT)–based diabetes diagnosis. We used the population-based Cooperative Health Research in the Region of Augsburg (KORA) follow-up survey, conducted in 2006–2008 in southern Germany (2,3) ( n = 2,611, aged 40–82 years). By means of participants’ self report and an OGTT, we identified individuals with previously diagnosed diabetes ( n = 233, 57.9% male, mean age 67.8 ± 8.7), undetected diabetes ( n = 109, 56.9% male, mean age 65.3 ± 10.4), and prediabetes (i.e., impaired glucose tolerance and/or impaired fasting glucose) ( n = 489, 53.2% male, mean age 63.7 ± 10.4), and those with normal …

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. Systematic review registration number PROSPERO CRD4201501780

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

BackgroundDiabetic 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/designWe 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 registrationPROSPERO CRD42015017809

Markedly Decreasing Incidence of Blindness in People With and People Without Diabetes in Southern Germany

OBJECTIVE Studies comparing the incidence of blindness in persons with and without diabetes are scarce worldwide. In Germany, a decline in the incidence of blindness was found during the 1990s. The aim of this study was to analyze the recent time trend. RESEARCH DESIGN AND METHODS Data were based on administrative files in southern Germany to assess recipients of blindness allowance newly registered between 1 January 2008 and 31 December 2012. We estimated age- and sex-standardized incidence of blindness in people with and people without diabetes and the corresponding relative risk. Poisson regression was used to examine age- and sex-adjusted time trends. RESULTS We identified 1,897 new cases of blindness (23.7% of which were associated with diabetes). We observed a strong decrease in incidence in both the population with diabetes (2008, 17.3 per 100,000 person-years [95% CI 13.6–21.1], and 2012, 8.9 per 100,000 person-years [6.3–11.6]: 16% decrease [10–22] per year) and that without diabetes (2008, 9.3 per 100,000 person-years [8.3–10.3], and 2012, 6.6 [5.8–7.4]: 9% decrease [5–13] per year). The relative risk comparing those incidences was 1.70 (95% CI 1.32–2.16) and remained constant in the observation period. Regarding time trend, we found similar results for both sexes. CONCLUSIONS We found a significant reduction in incidence of blindness in the populations with and without diabetes, which was more prominent among individuals with diabetes compared with the 1990s. Our findings may be explained by effective secondary prevention therapies and improved ophthalmologic care beyond diabetic retinopathy, particularly regarding macular degeneration, which means earlier detection and earlier and better treatment.

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.

Regional differences in antihyperglycemic medication are not explained by individual socioeconomic status, regional deprivation, and regional health care services. Observational results from the German DIAB-CORE consortium

Aims This population-based study sought to extend knowledge on factors explaining regional differences in type 2 diabetes mellitus medication patterns in Germany. Methods Individual baseline and follow-up data from four regional population-based German cohort studies (SHIP [northeast], CARLA [east], HNR [west], KORA [south]) conducted between 1997 and 2010 were pooled and merged with both data on regional deprivation and regional health care services. To analyze regional differences in any or newer anti-hyperglycemic medication, medication prevalence ratios (PRs) were estimated using multivariable Poisson regression models with a robust error variance adjusted gradually for individual and regional variables. Results The study population consisted of 1,437 people aged 45 to 74 years at baseline, (corresponding to 49 to 83 years at follow-up) with self-reported type 2 diabetes. The prevalence of receiving any anti-hyperglycemic medication was 16% higher in KORA (PR 1.16 [1.08–1.25]), 10% higher in CARLA (1.10 [1.01–1.18]), and 7% higher in SHIP (PR 1.07 [1.00–1.15]) than in HNR. The prevalence of receiving newer anti-hyperglycemic medication was 49% higher in KORA (1.49 [1.09–2.05]), 41% higher in CARLA (1.41 [1.02–1.96]) and 1% higher in SHIP (1.01 [0.72–1.41]) than in HNR, respectively. After gradual adjustment for individual variables, regional deprivation and health care services, the effects only changed slightly. Conclusions Neither comprehensive individual factors including socioeconomic status nor regional deprivation or indicators of regional health care services were able to sufficiently explain regional differences in anti-hyperglycemic treatment in Germany. To understand the underlying causes, further research is needed.

Decreasing rates of major lower-extremity amputation in people with diabetes but not in those without: a nationwide study in Belgium

Aims/hypothesisThe reduction of major lower-extremity amputations (LEAs) is one of the main goals in diabetes care. Our aim was to estimate annual LEA rates in individuals with and without diabetes in Belgium, and corresponding time trends.MethodsData for 2009–2013 were provided by the Belgian national health insurance funds, covering more than 99% of the Belgian population (about 11 million people). We estimated the age–sex standardised annual amputation rate (first per year) in the populations with and without diabetes for major and minor LEAs, and the corresponding relative risks. To test for time trends, Poisson regression models were fitted.ResultsA total of 5438 individuals (52.1% with diabetes) underwent a major LEA, 2884 people with above- and 3070 with below-the-knee major amputations. A significant decline in the major amputation rate was observed in people with diabetes (2009: 42.3; 2013: 29.9 per 100,000 person-years, 8% annual reduction, p < 0.001), which was particularly evident for major amputations above the knee. The annual major amputation rate remained stable in individuals without diabetes (2009: 6.1 per 100,000 person-years; 2013: 6.0 per 100,000 person-years, p = 0.324) and thus the relative risk reduced from 6.9 to 5.0 (p < 0.001). A significant but weaker decrease was observed for minor amputation in individuals with and without diabetes (5% and 3% annual reduction, respectively, p < 0.001).Conclusions/interpretationIn this nationwide study, the risk of undergoing a major LEA in Belgium gradually declined for individuals with diabetes between 2009 and 2013. However, continued efforts should be made to further reduce the number of unnecessary amputations.