Comparing the quality of care in physician networks to usual care for elderly patients in three German regions: a quasi-experimental cohort study.

OBJECTIVES: Patients in Germany have free choice of physicians in the ambulatory care sector and can consult them as often as they wish without a referral. This can lead to inefficiencies in treatment pathways. In response, some physicians have formed networks to improve the coordination and quality of care. This study aims to investigate whether the care provided by these networks results in better health and process outcomes than usual care. STUDY DESIGN: This was a quasi-experimental cohort study. METHODS: We analysed claims data from 2017 to 2018 in Bavaria, Brandenburg, and Westphalia-Lippe. Our study population includes patients aged 65 years or older with heart failure (n = 267,256), back pain (n = 931,672), or depression (n = 483,068). We compared condition-specific and generic quality indicators between patients treated in physician networks and usual care. Ambulatory care-sensitive emergency department cases were used as a primary outcome measure. Imbalances between the groups were minimized using propensity score matching. RESULTS: Rates of ambulatory care-sensitive emergency department cases yielded insignificant differences between networks and usual care in the depression and heart failure subgroups. For back pain patients, rates were 0.17 percentage points higher (P < 0.01) in network patients compared with usual care. Among network patients, generic indicators for prevention and coordination showed significantly better performance. For instance, the rate of completed vaccination against influenza is 3.03 percentage points higher (P < 0.01), and the rate of specialist visits after referral is 1.6 percentage points higher (P < 0.01) in heart failure patients, who are treated in physician networks. This is accompanied by higher rates of polypharmacy. Furthermore, the results for condition-specific indicators suggest that for most indicators, a greater proportion of the care provided by physician networks adhered to national treatment guidelines. CONCLUSIONS: Our findings suggest that physician networks in Germany do not reduce rates of ambulatory care-sensitive emergency department cases but perform better than usual care in terms of care coordination and prevention. Further research is needed to confirm our findings and explore the implications of the potentially higher rates of polypharmacy seen in physician networks.

Mismatch repair deficiency, chemotherapy and survival for resectable gastric cancer: an observational study from the German staR cohort and a meta-analysis.

PURPOSE: In a post hoc analysis of the MAGIC trial, patients with curatively resected gastric cancer (GC) and mismatch repair (MMR) deficiency (MMRd) had better median overall survival (OS) when treated with surgery alone but worse median OS when treated with additional chemotherapy. Further data are required to corroborate these findings. METHODS: Between April 2013 and December 2018, 458 patients with curatively resected GC, including cancers of the esophagogastric junction Siewert type II and III, were identified in the German centers of the staR consortium. Tumor sections were assessed for expression of MLH1, MSH2, MSH6 and PMS2 by immunohistochemistry. The association between MMR status and survival was assessed. Similar studies published up to January 2021 were then identified in a MEDLINE search for a meta-analysis. RESULTS: MMR-status and survival data were available for 223 patients (median age 66 years, 62.8% male), 23 patients were MMRd (10.3%). After matching for baseline clinical characteristics, median OS was not reached in any subgroup. Compared to perioperative chemotherapy, patients receiving surgery alone with MMRd and MMRp had a HR of 0.67 (95% CI 0.13-3.37, P = 0.63) and 1.44 (95% CI 0.66-3.13, P = 0.36), respectively. The meta-analysis included pooled data from 385 patients. Compared to perioperative chemotherapy, patients receiving surgery alone with MMRd had an improved OS with a HR of 0.36 (95% CI 0.14-0.91, P = 0.03), whereas those with MMRp had a HR of 1.18 (95% CI 0.89-1.58, P = 0.26). CONCLUSION: Our data support a positive prognostic effect for MMRd in GC patients treated with surgery only and a differentially negative prognostic effect in patients treated with perioperative chemotherapy. MMR status determined by preoperative biopsies may be used as a predictive biomarker to select patients for perioperative chemotherapy in curatively resectable GC.

OR.NET: multi-perspective qualitative evaluation of an integrated operating room based on IEEE 11073 SDC.

PURPOSE: Clinical working environments have become very complex imposing many different tasks in diagnosis, medical treatment, and care procedures. During the German flagship project OR.NET, more than 50 partners developed technologies for an open integration of medical devices and IT systems in the operating room. The aim of the present work was to evaluate a large set of the proposed concepts from the perspectives of various stakeholders. METHOD: The demonstration OR is focused on interventions from the head and neck surgery and was developed in close cooperation with surgeons and numerous colleagues of the project partners. The demonstration OR was qualitatively evaluated including technical as well as clinical aspects. In the evaluation, a questionnaire was used to obtain feedback from hospital operators. The clinical implications were covered by structured interviews with surgeons, anesthesiologists and OR staff. RESULTS: In the present work, we qualitatively evaluate a subset of the proposed concepts from the perspectives of various stakeholders. The feedback of the clinicians indicates that there is a need for a flexible data and control integration. The hospital operators stress the need for tools to simplify risk management in openly integrated operating rooms. CONCLUSION: The implementation of openly integrated operating rooms will positively affect the surgeons, the anesthesiologists, the surgical nursing staff, as well as the technical personnel and the hospital operators. The evaluation demonstrated the need for OR integration technologies and identified the missing tools to support risk management and approval as the main barriers for future installments.

Inflammation, vitamin D and dendritic cell precursors in chronic kidney disease.

Decreased blood dendritic cell precursors (DCP) count is linked with atherosclerotic disease, while reduction of circulating DCP is also seen in patients with chronic kidney disease (CKD). As poor vitamin D status could be linked to a compromised innate immune response, we hypothesized that vitamin D status might be involved in the decrease in circulating DCP in CKD. Moreover, the potential role of inflammation was considered. Circulating myeloid (mDCP), plasmacytoid (pDCP) and total DCP (tDCP) were analysed using flow cytometry in 287 patients with CKD stage 3. Serum 25(OH)D and 1,25(OH)2D levels were measured using enzyme-linked immunosorbent assays (ELISA), interleukin (IL)-6, IL-10 and tumour necrosis factor (TNF)-α using cytometric bead array, C-reactive protein (CRP) using a high-sensitivity (hs) ELISA. Contrary to our hypothesis, there was no association between vitamin D levels and DCP, although their number was decreased significantly in CKD (P < 0·001). Instead, mDCP (r = -0·211) and tDCP (r = -0·188,) were associated slightly negatively with hsCRP but positively with the estimated glomerular filtration rate (eGFR, r = 0·314 for tDCP). According to multivariate linear regression, only higher hsCRP concentration and the presence of diabetes mellitus had a significant negative influence on DCP count (P < 0·03, respectively) but not vitamin D, age and eGFR. A significant impact of vitamin D on the reduction of circulating DCP in CKD 3 patients can be neglected. Instead, inflammation as a common phenomenon in CKD and diabetes mellitus had the main influence on the decrease in DCP. Thus, a potential role for DCP as a sensitive marker of inflammation and cardiovascular risk should be elucidated in future studies.

[Mason I fracture - a simple injury?]. / Mason-I-Fraktur - eine harmlose Verletzung?

BACKGROUND: Mason I fractures of the radial head are judged to be simple injuries that can generally be treated nonoperatively. According to the current literature mainly good and excellent results can be expected. We present a case series of patients presenting to us due to complications of Mason I fractures. PATIENTS AND METHODS: We reviewed all cases of patients that were treated because of complaints following Mason I radial head fractures. In all, 16 patients (10 men and 6 women) were identified. Mean age was 37 years (range 16-59 years). Mean time between trauma and surgery was 25 months (range 1-108 months). RESULTS: Ten patients developed painful osteoarthritis with elbow stiffness and loose bodies, 4 patients suffered a posterolateral rotatory instability that had to be treated with ligament reconstruction, 1 patient presented with a combined medial and lateral instability, and 1 patient with a symptomatic hypertophic plica posterolateralis. Diagnotics and therapeutic concepts of these complications will be presented. CONCLUSION: In light of the complications, Mason I fractures must be reevaluated. They remain the domain of conservative treatment but close follow-up is recommended to recognize possible complications early in order to prevent stiffness, chronic instabilities, and osteoarthritis.

High serum pentosidine but not esRAGE is associated with prevalent fractures in type 1 diabetes independent of bone mineral density and glycaemic control.

UNLABELLED: Fracture risk in type 1 diabetes (T1D) is supposed to be underestimated by bone mineral density (BMD). Individuals with T1D had more prevalent fractures in a cross-sectional study. Serum levels of pentosidine, an advanced glycation end product, and poor glycaemic control were associated with prevalent fractures independent of BMD. INTRODUCTION: Type 1 diabetes (T1D) is associated with increased fracture risk. Bone mineral density (BMD) underestimates the risk of fractures in some individuals. The accumulation of advanced glycation end products (AGEs) impairs bone matrix and reduces bone strength. METHODS: In a cross-sectional study, 128 men and premenopausal women with T1D were evaluated. We compared traditional risk factors for fractures, BMD, parameters of bone metabolism and AGEs in individuals with and without prevalent fractures. An independent association of serum AGE levels with prevalent fractures was investigated. RESULTS: Individuals with prevalent fractures exhibited a longer duration of T1D, higher HbA1c and more diabetic-related complications. BMD at the femoral neck (z-score -0.76 ± 0.94 vs. -0.23 ± 1.02; p = 0.031) and total hip (z-score -0.54 ± 0.93 vs. 0.11 ± 1.11; p = 0.017) was lower in those with prevalent fractures. Individuals with fractures had higher pentosidine levels (164.1 ± 53.6 vs. 133.2 ± 40.4; p = 0.002). The levels of N-ε-(carboxymethyl)-lysine (CML) and endogenous secretory receptor for AGEs (esRAGE) did not significantly differ. Multivariate logistic regression analysis adjusted for age, BMI, family history of fractures, smoking, vitamin D deficiency, BMD at lumbar spine, femoral neck and total hip identified pentosidine levels and HbA1c as independent factors associated with prevalent fractures (odds ratio 1.02, 95% CI 1.00-1.03/pmol/ml increase of pentosidine; p = 0.008 and odds ratio 1.93, 95% CI 1.16-3.20 per percentage increase of HbA1c; p = 0.011). CONCLUSIONS: The pentosidine levels but not BMD are independently associated with prevalent fractures. Impaired bone quality in T1D may result from increased AGE formation.

[Transosseous refixation of the common extensor muscle tendons in chronic lateral epicondylitis with and without additional reconstruction of the LUCL--a retrospective evaluation of 101 patients]. / Die transossäre Refixation der Extensoren bei chronischer radialer Epikondylopathie mit und ohne Rekonstruktion des LUCL-Komplexes--eine retrospektive Analyse von 101 Patienten.

INTRODUCTION: The chronic lateral epicondylitis (EHR) as a common pathology of the elbow is often associated with posterolateral rotatory instability of the elbow (PLRI). After evaluation of intra-articular pathology by prior diagnostic arthroscopy, we aimed to build patient groups regarding the stability of the elbow joint. In patients with a stable elbow joint, open surgery with a debridement to the origin of the common extensor tendon and transosseous refixation was performed. Patients with relevant posterolateral rotatory instability, however, underwent an additional LUCL complex stabilisation using triceps tendon graft besides debridement as mentioned above. The purpose of this study was to evaluate and compare the clinical functional outcome between these groups. MATERIAL AND METHODS: 101 patients were included in our study. Arthroscopies were first performed on all patients to identify intra-articular pathological changes. In 26 patients with stable elbows, open surgery with debridement to the origin of the common extensor tendon and transosseous refixation was performed. For the other 75 patients who were found presenting a relevant posterolateral rotatory instability, a stabilisation of the LUCL in addition to the open procedure mentioned above was performed. Examinations and questionnaires were used for retrospective evaluation at follow-up. RESULTS: Both groups of patients revealed significant improvement in pain relief and elbow function. We observed no significant difference between the two methods concerning clinical and functional outcome. CONCLUSION: We recommend diagnostic arthroscopy with assessment of stability prior to the open performance to offer a more reliable evidence for surgical technique selection and therefore to achieve a better clinical outcome.

[Psycho-oncology]. / Psychoonkologie.

Psycho-oncology addresses the psychosocial care of patients with cancer. Systematic research on the interactions between biological, psychological and social factors before, during and after cancer has only been carried out for a few decades. All cancer patients, their relatives and the treating medical team should receive low-threshold offers for psychosocial support. The demand for interdisciplinary counselling and therapy detected by clinical diagnosis and by systematic screening, is not satisfactorily covered and is continuously increasing. In collaboration between the involved professional groups, education and professional qualifications for psycho-oncologists are still being developed.

Therapeutic options for acute and chronic elbow instability.

INTRODUCTION: Acute elbow instability usually develops after injuries involving the bony or ligamentous stabilizers of the joint. It occurs frequently after dislocation and/or fracture-dislocation, but isolated valgus or varus overloading can also lead to ligament ruptures with subsequent instability. Chronic instability can result from incompletely healed acute injuries or from recurring microtrauma, for example after repetitive strain from participating in certain sports. CONCLUSION: Stable conditions of the joint are essential for early functional post-traumatic or postoperative treatment of the elbow, as permanent mobility deficits may result otherwise. The following article gives an overview of the current understanding of these injuries and concepts in treatment.

Advanced glycation end products affect growth and function of osteoblasts.

OBJECTIVES: Advanced glycation end products (AGEs) have been implicated in the pathogenesis of bone-destructive disorders. Yet reports on the influence of AGEs on human osteoblasts remain lacking. The aim of the study is to investigate the influence of AGE-modified bovine serum albumin (AGE-BSA) on cell growth and expression of osteoblastic markers associated with osteogenesis and osteoclastogenesis. METHODS: Human osteoblasts established from bone tissue specimens were stimulated with AGE-BSA and investigated in vitro. Expression of mRNA for the receptor for AGEs (RAGE), nuclear factor kappa B subunit p65 (NFκB p65), tumour necrosis factor alpha (TNF-α), matrix metallo proteinase-1 (MMP-1), receptor activator of NFκB ligand (RANKL), osteoprotegerin, collagen type I (Col1), osteocalcin (OC) and alkaline phosphatase (ALP) were measured using real-time polymerase chain reaction (PCR). Respective protein expressions were evaluated by western blot analysis or ELISA. NFκB activation was investigated by luciferase assay and electrophoretic mobility shift assay (EMSA). Cell cycle analysis, cell proliferation and markers of necrosis and early apoptosis were assessed. RESULTS: AGE-BSA was actively taken up into osteoblasts and induced cell cycle arrest and an increase in necrotic, but not apoptotic cells. The increased expression of RAGE and TNF-α together with NFκB activation indicates an AGE-mediated inflammatory response. The decreased expression of Col1, OC and ALP presumably reflects a diminished osteogenic potential, whereas upregulation of RANKL and TNF-α enhances osteoclastogenesis. CONCLUSIONS: The present study demonstrates that AGE-BSA affects the growth and function of osteoblasts. Modulation of the expression of various target genes involved in bone metabolism provides evidence that AGEs accumulated in the bone matrix have the potential to suppress osteogenic and to promote osteoclastogenic properties of osteoblasts in vivo, thereby leading to functional and structural impairment of bone.

Decreased RAGE expression in peripheral blood mononuclear cells of patients with rheumatoid arthritis.

OBJECTIVE: Interactions between the multiligand receptor for advanced glycation end products (RAGE) and its proinflammatory ligands (AGEs, S100/calgranulins, HMBG1, Mac-1) may contribute to inflammatory responses playing a key role in the pathogenesis of chronic inflammatory diseases such as in rheumatoid arthritis (RA). Peripheral blood mononuclear cells (PBMCs) participate in the development of chronic inflammatory diseases. This study investigated expression of the RAGE variants endogenous secretory RAGE (esRAGE), N-truncated RAGE (NtRAGE) and complete RAGE (cRAGE: encoding full-length RAGE, esRAGE and NtRAGE) in PBMCs of patients with RA in comparison to healthy control subjects (controls) and to patients with Crohn's disease (CD) as another chronic inflammatory disease. METHODS: The cRAGE, esRAGE and NtRAGE mRNA expression levels of PBMCs from controls, RA and CD patients were measured by real-time PCR. The RAGE protein expression was determined by Western blot analysis and the esRAGE plasma levels by ELISA. RESULTS: PBMCs of RA patients showed significantly decreased mRNA expression for cRAGE (46%), esRAGE (54.0%) and NtRAGE (52%) in comparison to healthy controls (100%). For CD patients, also a down-regulation but to a lower extent was found (cRAGE: 79%; esRAGE: 76%; NtRAGE: 69%). Related to controls, RA PBMCs showed a significantly reduced protein expression of full-length RAGE (53%) as well as significantly decreased esRAGE plasma concentrations (70%). CONCLUSION: The down-regulation of RAGE isoforms in RA PBMCs may contribute to reduced intracellular responses mediated by the cell-standing receptor as well as to a lowered capability of trapping inflammatory ligands by circulating esRAGE.

Guidelines for an integrated diagnostic approach of chronic lymphoproliferative disorders in the routine laboratory of haematology in Belgium.

This paper summarizes the minimal workout of chronic lymphoproliferative disorders in a routine laboratory of haematology as recommended by a team of experienced laboratory supervisors in Belgium, taking into account the specific organisation of healthcare in Belgium, the innovations in the field of molecular analyses and related reimbursement. The starting point was essentially based upon clinical and/or haematological indications and it is emphasized that conclusions should be drawn in close dialogue with the clinician and experts in cytogenetics and histopathology. Reports made in the laboratory should be based upon an integration of cytomorphological, immunophenotypical and molecular data. These guidelines are not intended to be used as universal 'diagnostic pathways', but should be useful in developing local diagnostic pathways. It is well understood that this consensus, being valid anno 2009, may rapidly change with new technologies being introduced and new targets discovered.

Soluble receptor activator of NFkappa B-ligand and osteoprotegerin in rheumatoid arthritis - relationship with bone mineral density, disease activity and bone turnover.

The aim of our study was to investigate determinants of bone mineral density (BMD) measured by dual X-ray absorptiometry at the lumbar spine (BMD-LS) and at the femoral neck (BMD-FN) in patients with rheumatoid arthritis (RA) with special respect to bone resorbing proinflammatory cytokines and their physiological antagonists. In 142 RA patients the following parameters were measured in parallel with BMD: serum levels of soluble receptor activator of nuclear factor kappa-B-ligand (sRANKL), osteoprotegerin (OPG), interleukin (IL)-6, soluble glycoprotein 130 (sgp130), 25-hydroxyvitamin D3 (25OHD(3)), 1,25-dihydroxyvitamin D3 (1,25[OH](2)D(3)), intact parathyroid hormone, osteocalcin, ionized calcium, renal excretion of pyridinolin and deoxypyridinolin, C-reactive protein, and erythrocyte sedimentation rate (ESR). No significant differences of sRANKL, OPG, IL-6, and spg130 were found between patients with osteoporosis (47.9% of patients), osteopenia (36.6%), and normal BMD (15.5%). However, total sRANKL was significantly higher in postmenopausal women with osteoporosis at FN than in those without (p < 0.05) and showed a negative correlation with BMD-LS in patients older than 60 years (p = 0.01). BMD-LS and BMD-FN (p < 0.001) and total sRANKL (p < 0.01) were negatively related with the age of the patients. Only IL-6 (positive correlation, p < 0.001) and 1,25(OH)(2)D(3) (negative correlation, p < 0.001) but not sRANKL, OPG, and sgp130 were related to disease activity. Using multiple linear regression analysis, menopause was identified as the crucial negative determinant of BMD-LS (R (2) = 0.94, p = 0.001), whereas cumulative glucocorticoid dose (beta = -0.80, p = 0.001) and ESR (beta = -0.44, p = 0.016) were the negative determinants of BMD-FN (R (2) = 0.86, p = 0.001). The results indicate that influences of age and gender must be considered in investigations on the relationship between BMD and sRANKL in RA and that high serum levels of sRANKL seems to be associated with osteoporosis only in subgroups of RA patients.

[Age-dependent prioritisation of health-care spending--perspectives for the German health-care system]. / Altersabhängige Priorisierung von Gesundheitsleistungen--Perspektiven für das deutsche Gesundheitswesen.

Expenditure on health care has been rising for years. Also, the ageing population is a matter of fact. Generally, ageing goes along with higher expenditure for health care. Debates about the financial situation and solution for this situation are common. This article examines the impact of all aspects of ageism with regard to the expenditure in health care. Besides, for the practical effects of rationing, a multidimensional approach is illustrated. The article discusses the concept of age-dependent prioritisation of health-care spending.

Advanced glycation end product modification of bone proteins and bone remodelling: hypothesis and preliminary immunohistochemical findings.

BACKGROUND: The process of bone remodelling is disturbed in the development of osteoporosis. OBJECTIVE: To investigate if proteins in osteoporotic bone are modified by advanced glycation end products (AGEs), and whether these alterations are related to measures of bone remodelling based on histomorphometric findings. METHODS: Bone specimens taken from the iliac crest by bone biopsy of eight osteoporotic patients were investigated by histomorphometry and by immunohistochemical staining with the AGEs imidazolone and N(epsilon)-carboxymethyllysine. RESULTS: Both AGEs were found in all bone specimens. The intensity of staining correlated with patient age. The percentage of bone surface covered with osteoblasts showed a significantly negative correlation with the staining intensity of both AGEs. CONCLUSIONS: It is known that AGEs can regulate proliferation and differentiation of osteoblastic cells and that AGE-specific binding sites are present in cultured osteoblast-like cells. Moreover, AGE induced biological effects in these cells might be mediated by RAGE (receptor of AGE) or by other AGE receptors in different stages of osteoblast development. The inverse relation between AGE staining intensity and the percentage of bone surface covered with osteoblasts in the trabecular bone may provide evidence that AGE modification of bone proteins disturbs bone remodelling.

Detection of elevated N epsilon-carboxymethyllysine levels in muscular tissue and in serum of patients with fibromyalgia.

OBJECTIVES: To compare levels of the advanced glycation end product (AGE) N(epsilon)-carboxymethyllysine (CML) present in the muscle tissue and in the serum of patients with fibromyalgia (FM) vs. healthy controls. METHODS: The serum levels of CML were measured in 41 patients with FM and 81 healthy controls. The presence of CML, nuclear factor kappa B (NF-kappaB), the AGE receptor (RAGE), collagen types I, II, VI, and CD68-positive monocytes/macrophages in muscle tissue of 14 patients with FM was investigated by immunohistochemistry. RESULTS: Patients with FM showed significantly increased serum levels of CML in comparison to healthy controls. The immunohistochemical investigation revealed a stronger staining for CML and NF-kappaB and more CD68-positive monocytes/macrophages in the muscle of FM patients. The collagens and CML were co-localized, suggesting that the AGE modifications were related to collagen. RAGE was absent in controls but a faint and patchy staining was seen in FM. CONCLUSIONS: In the interstitial connective tissue of fibromyalgic muscles we found a more intensive staining of the AGE CML, activated NF-kappaB, and also higher CML levels in the serum of these patients compared to the controls. RAGE was only present in FM muscle. AGE modification of proteins causes reduced solubility and high resistance to proteolytic digestion of the altered proteins (e.g. AGE-modified collagens). AGEs can stimulate different types of cells by activation of the transcription factor NF-kappaB, mediated by specific receptors of AGEs (e.g. RAGE) on the cell surface. Both mechanisms may contribute to the development, perpetuation, and spreading of pain characteristic in FM patients.

Species-dependent premature degradation of absorbable suture materials caused by infection--impact on the choice of thread in vascular surgery.

BACKGROUND: In case of infection after vascular reconstruction, preference is often given to absorbable suture material with the aim of preventing persistence of infection. We have investigated the functional deficit of absorbable sutures on incubation with various different bacteria. MATERIAL AND METHODS: Four suture materials Dexon bicolor, Vicryl, Maxon and PDS II--were placed in contact with reference bacterial cultures (Staphylococcus aureus, Pseudomonas aeroginosa, E. coli, coagulase-negative staphylococci and Proteus mirabilis). The bacteria were incubated for 7 days at 37 degrees C, together with the suture material. A logarithmic phase (Group A) and a static phase (Group B) were simulated. The linear tensile strength (LTS) of the suture material was measured (Instron Tensiometer). RESULTS: In the case of Staphylococcus aureus, a significant decrease in LTS was established for Dexon bicolor (group A: 31%, group B: 22%), and Vicryl (53% and 43%), but not for the monofilament threads. With regard to the other bacteria, a considerably more dramatic effect was observed: in both groups the braided sutures had completely disintegrated after 7 days. The monofilament sutures also revealed a significant loss of function (Maxon: 88%, PDS II 66%). CONCLUSIONS: The absorbable sutures revealed a premature, species-dependent loss of function due to the presence of the bacteria. On the basis of our results, the use of absorbable threads for vessel sutures in case of infection cannot be recommended, with the exception of monofilament material in a monocultural Staphylococcus aureus infection.

Influence of hemodialysis membrane permeability on serum levels of advanced glycation end products (AGEs) and homocysteine metabolites.

BACKGROUND: [corrected] Advanced glycation end products (AGEs), total homocysteine (tHcy) and the homocysteine metabolites cystathionine (Cysta) and dimethylglycine (DMG) are increased in serum of patients with end-stage renal disease. The aim of this prospective randomized study was to compare the efficacy of polysulfone high-flux vs. polysulfone low-flux hemodialysis (HD) treatment regarding removal of AGEs, tHcy, Cysta and DMG. PATIENTS AND METHODS: Twenty-nine patients on chronic HD treatment were randomly assigned to 2 groups in a 3-period 2-treatment design with low flux (A)--high flux (B)--low flux (A) for group I and B-A-B for group II, 6 weeks each period. The following parameters were measured in pre- and postdialytic serum samples at baseline and the end of each period: total serum fluorescence, Nepsilon-carboxymethyllysine (CML), free and protein-bound pentosidine, tHcy, Cysta and DMG. RESULTS: There was increased removal of free pentosidine during high-flux HD treatment compared to low-flux HD treatment, attaining significance between the second and third treatment periods (group 1: 86.0 +/- 4.7% vs. 79.2 +/- 8.8%, p = 0.007; group II: 84.0 +/- 6.3% vs. 79.8 +/- 9.8%, p = 0.049 for high vs. low flux). The intradialytic reduction rates for total serum fluorescence, tHcy, Cysta, DMG did not differ between high- and low-flux HD treatment. Protein-bound pentosidine and CML did not decrease during the dialysis sessions, neither with high-flux nor with low-flux HD membrane. Despite a strong decrease during single HD session, the predialytic levels of free pentosidine, tHcy, Cysta and DMG remained unchanged during the study period both for high- and low-flux HD treatment. CONCLUSION: The more pronounced effect of high-flux dialysis on the removal rate of free pentosidine, found in this randomized crossover study, could not translate into a significant difference in predialysis levels after a 6-week treatment period. We could not find any differences between polysulfone high- and low-flux membranes for lowering predialytic serum concentrations of the measured AGEs, which are mainly bound on albumin.

Effect of smoking on risk factors for cardiovascular disease in patients with diabetes mellitus and renal insufficiency.

BACKGROUND: Many studies have been published demonstrating a strong correlation between smoking, renal lesions and cardiovascular morbidity and mortality. Possible contributing factors are elevated blood pressure values, changes in vascular reactivity, concentrations of lipids, fibrinogen and carboxyhemoglobin, in patients with diabetes mellitus, the quality of diabetes control and insulin resistance. Other possible risk factors may include advanced glycation end (AGE)-products, total plasma homocysteine and metabolites as well as symmetrical (SDMA) and asymmetrical (ADMA) dimethylarginine. It was the goal of the present trial to investigate the serum concentrations of these >new<, possible risk factors in a selection free population of patients with type 1 and insulin-treated type 2 diabetes mellitus, in patients with chronic renal insufficiency and in renal transplant recipients. The second aim was to analyse the effect of cigarette smoking on the levels of these laboratory parameters. PATIENTS AND METHODS: A total of 544 subjects (n = 98 patients with chronic renal insufficiency without hemodialysis, n = 84 patients with hemodialysis, n = 50 renal transplant recipients, n = 114 patients with type 1 and n = 147 patients with insulin treated type 2 diabetes mellitus, n = 51 healthy controls) participated in the trial. RESULTS: Patients with renal insufficiency had significantly higher concentrations of the AGE-products N-epsilon-Carboxymethyllysine (CML) and pentosidine compared with both groups of patients with insulin-treated diabetes mellitus and the healthy controls. In patients with type 1 diabetes there was a positive correlation between HbA1c and the concentration of CML (r = 0.405, p = 0.017) and between the pentosidine-concentration and the serum creatinine-level (r = 0.482, p = 0.001). In type 2 diabetes there was a correlation between CML and diastolic blood pressure (r = 0.239, p = 0.039). In comparison to the healthy controls, patients with renal diseases and patients after kidney transplantation had higher concentrations of total plasma homocysteine and its metabolites. Similar results were found for SDMA and ADMA: Patients with chronic renal insufficiency both with and without hemodialysis had significantly higher values than the renal transplant recipients and healthy controls. A clear influence of cigarette smoking on the levels of the laboratory parameters measured could not be determined in any group; neither in the patients with diabetes mellitus, nor in the patients with renal diseases, nor in the healthy controls. CONCLUSIONS: The present trial demonstrates an increase in the parameters linked to the development of cardiovascular diseases including total plasma homocysteine, its metabolites, the dimethylarginines SDMA and ADMA and advanced glycation end-products depending on the degree of renal insufficiency. Moreover, in patients with insulin-treated diabetes mellitus, the concentrations of the AGE-products CML and pentosidine seem to be strongly influenced by the quality of diabetes control and blood pressure levels. There was no influence of cigarette smoking on the levels of the laboratory parameters measured.

Serum levels of total homocysteine, homocysteine metabolites and of advanced glycation end-products (AGEs) in patients after renal transplantation.

AIMS: Hyperhomocysteinemia has been described as an independent risk factor for cardiovascular diseases (CVD) influencing patient outcome. Advanced glycation end-products (AGEs) are involved in the pathogenesis of vascular damage in uremia. This study was undertaken to assess whether high serum levels of total homocysteine (tHcy) with its metabolites methylmalonic acid (MMA), methylcitric acid (MCA) and cystathionine (CYSTA) as well as elevated serum concentrations of the AGEs pentosidine and Nepsilon-carboxymethyllysine (CML) are independent risk factors for CVD, left ventricular hypertrophy (LVH) or hypertension as well as kidney dysfunction in renal transplant recipients (RTR). METHODS: Serum levels of tHCy, MMA, MCA and CYSTA were measured by a gas chromatographic-mass spectrometric assay, pentosidine by HPLC and CML using an ELISA assay. RESULTS: All measured parameters were significantly higher in RTRs than in healthy subjects (p < 0.0001). The levels of pentosidine and CML as well as of tHcy and its metabolites correlated significantly with each other, but not with those ofMMA and CYSTA. Significant correlations were also found between pentosidine and tHcy, MMA or MCA as well as between CML, MMA and MCA, respectively. Acute or chronic rejection did not influence these values. No significant differences were observed between patients with or without CVD or with hypertension. In RTRs with LVH, only the tHcy levels were significantly higher than in those RTRs without LVH (p = 0.006). Logistic regression analysis revealed an independent influence of tHcy on the presence of LVH. CONCLUSION: These results may indicate an association between high tHcy values and LVH. Further investigation is needed to determine whether a reduction of tHcy and Hcy metabolites and/or AGE serum concentrations would significantly improve patient outcome after undergoing renal transplantation.