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OBJECTIVE: We investigated associations between gastrointestinal symptoms - evaluated as a combined weighted symptom score (CWSS) - Diabetic autonomic neuropathy (DAN), and distal symmetrical polyneuropathy (DSPN) in type 1 and type 2 diabetes. RESEARCH DESIGN AND METHODS: Cross-sectional study in a tertiary outpatient clinic. CWSS was calculated based on questionnaires: gastroparesis composite symptom index (GCSI) and gastrointestinal symptom rating score (GSRS). DAN and DSPN were addressed using the composite autonomic symptom score 31 (COMPASS-31) questionnaire, cardiac autonomic reflex tests (CARTs), electrochemical skin conductance (ESC), vibration perception threshold (VPT), Michigan Neuropathy Screening Instrument (MNSI), pain- and thermal sensation. Analyses were adjusted for age, sex, diabetes duration, smoking, LDL-cholesterol, HbA1C and systolic blood pressure. Type 1 and type 2 diabetes were evaluated separately. RESULTS: We included 566 with type 1 diabetes and 377 with type 2 diabetes. Mean ± SD age was 58 ± 15 years and 565 (59.9 %) were women. A high CWSS was present in 143 (25 %) with type 1 and 142 (38 %) with type 2 diabetes. The odds of DAN by COMPASS-31 (p < 0.001) were higher in the high score group. For type 1 diabetes, odds of cardiac autonomic neuropathy were higher in the high CWSS group. The odds of DSPN by VPT and MNSI in type 1 diabetes, and by ESC, VPT and pain sensation in type 2 diabetes were higher in the high CWSS group. CONCLUSIONS: A high symptom score was associated with neuropathy by COMPASS-31 and vibration perception. Gastrointestinal symptom burden associated inconsistently with other neuropathy tests between diabetes types.
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Diabetes Mellitus Tipo 1 , Diabetes Mellitus Tipo 2 , Neuropatias Diabéticas , Populações Escandinavas e Nórdicas , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doenças do Sistema Nervoso Autônomo/diagnóstico , Doenças do Sistema Nervoso Autônomo/epidemiologia , Doenças do Sistema Nervoso Autônomo/fisiopatologia , Doenças do Sistema Nervoso Autônomo/complicações , Estudos de Coortes , Efeitos Psicossociais da Doença , Estudos Transversais , Dinamarca/epidemiologia , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/fisiopatologia , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/fisiopatologia , Neuropatias Diabéticas/diagnóstico , Neuropatias Diabéticas/epidemiologia , Neuropatias Diabéticas/fisiopatologia , Gastroenteropatias/epidemiologia , Gastroenteropatias/diagnóstico , Gastroenteropatias/complicações , Gastroenteropatias/fisiopatologia , Gastroenteropatias/etiologia , Índice de Gravidade de Doença , Inquéritos e Questionários , Carga de SintomasRESUMO
Background: The Dapagliflozin and Prevention of Adverse Outcomes in CKD (DAPA-CKD) trial enrolled patients with estimated glomerular filtration rate 25-75 mL/min/1.73 m2 and urine albumin-to-creatinine ratio >200 mg/g. The Dapagliflozin Effect on CardiovascuLAR Events-Thrombolysis in Myocardial Infarction 58 (DECLARE-TIMI 58) trial enrolled patients with type 2 diabetes, a higher range of kidney function and no albuminuria criterion. The study objective was to estimate the cost-effectiveness of dapagliflozin in a broad chronic kidney disease population based on these two trials in the UK, Spain, Italy and Japan. Methods: We adapted a published Markov model based on the DAPA-CKD trial but to a broader population, irrespective of urine albumin-to-creatinine ratio, using patient-level data from the DAPA-CKD and DECLARE-TIMI 58 trials. We sourced cost and utility inputs from literature and the DAPA-CKD trial. The analysis considered healthcare system perspectives over a lifetime horizon. Results: Treatment with dapagliflozin was predicted to attenuate disease progression and extend projected life expectancy by 0.64 years (12.5 versus 11.9 years, undiscounted) in the UK, with similar estimates in other settings. Clinical benefits translated to mean quality-adjusted life year (QALY; discounted) gains between 0.45 and 0.68 years across countries. Incremental cost-effectiveness ratios in the UK, Spain, Italy and Japan ($10 676/QALY, $14 479/QALY, $7771/QALY and $13 723/QALY, respectively) were cost-effective at country-specific willingness-to-pay thresholds. Subgroup analyses suggest dapagliflozin is cost-effective irrespective of urinary albumin-to-creatine ratio and type 2 diabetes status. Conclusion: Treatment with dapagliflozin may be cost-effective for patients across a wider spectrum of estimated glomerular filtration rates and albuminuria than previously demonstrated, with or without type 2 diabetes, in the UK, Spanish, Italian and Japanese healthcare systems.
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BACKGROUND: Regular monitoring is required to ensure that patients who have, or are at risk of, chronic kidney disease (CKD) receive appropriate management. Guidelines recommend regular testing of estimated glomerular filtration rate (GFR) and albuminuria. However, evidence suggests that albuminuria testing rates, specifically urine albumin-to-creatinine ratio (UACR), are suboptimal. AIM: To assess published evidence relating to the drivers of non-adherence to albuminuria testing guidelines and the impact of not identifying CKD across the course of progression. MATERIALS AND METHODS: A systematic review of five bibliographic databases was conducted, supplemented by hand searches of relevant conference abstracts. RESULTS: One study was identified that reported drivers of non-adherence to albuminuria testing guidelines. The largest barrier was the perception that testing does not impact patient management. Thirteen studies were identified that evaluated the impact of not identifying CKD patients. All included studies analyzed the effect of not identifying worsening CKD severity leading to late referral (LR). 12/13 studies reported only on clinical impact, and 1/13 reported on clinical and economic impact. LR led to higher costs and worse outcomes than early referral, including higher rates of mortality and worsened kidney replacement therapy preparation. CONCLUSION: This systematic review demonstrates a gap in evidence exploring the drivers of non-adherence to albuminuria testing guidelines and the impact of not identifying patients in the early stages of CKD. Guideline-recommended testing allows timely identification, referral, and treatment for patients with, or at risk of, CKD, providing the best chance of avoiding the worsened outcomes identified in this review.
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Albuminúria , Insuficiência Renal Crônica , Humanos , Albuminúria/diagnóstico , Suplementos Nutricionais , Encaminhamento e Consulta , Insuficiência Renal Crônica/diagnósticoRESUMO
AIM: To estimate the health economic impact of undertaking urine albumin-to-creatinine ratio (UACR) testing versus no UACR testing in early stages of chronic kidney disease (CKD) progression in patients with type 2 diabetes (T2D). METHODS: An economic model, taking a UK healthcare system perspective, estimated the impact of UACR testing on additional costs, clinical benefits measured as prevented dialyses and cardiovascular-related deaths, life years gained (LYg), LYg before kidney failure, and incremental cost-effectiveness ratio (ICER). Sixteen of the 18 Kidney Disease: Improving Global Outcomes (KDIGO) heatmap categories were considered separately, and grouped in health states according to CKD risk. Results were derived for current standard-of-care and emerging CKD therapies. RESULTS: The cohort that adhered to both UACR and estimated glomerular filtration rate (eGFR) testing guidelines in early stages of CKD (n = 1000) was associated with approximately 500 LYg before kidney failure onset; costing approximately £2.5 M. ICERs across the KDIGO heatmap categories were approximately £5,000. LIMITATIONS: This model used data from a comprehensive meta-analysis that was initiated more than 10 years ago (2009). While this was the most comprehensive source identified, recent changes in the treatment landscape, patient population and social determinants of CKD will not be captured. Furthermore, a narrow approach was taken, aligning included costs with UK NHS reference materials. This means that some direct and indirect drivers of costs in late-stage disease have been excluded. CONCLUSIONS: UACR testing in the early stages of CKD is cost effective in T2D patients. Emerging therapies with the potential to slow CKD progression, mean that optimal monitoring through UACR/eGFR testing will become increasingly important for accurate identification and timely treatment initiation, particularly for the highest-risk A3 category.
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Diabetes Mellitus Tipo 2 , Insuficiência Renal Crônica , Humanos , Taxa de Filtração Glomerular , Creatinina/urina , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/epidemiologia , Albuminúria/epidemiologia , Albuminúria/urina , Insuficiência Renal Crônica/epidemiologia , AlbuminasRESUMO
BACKGROUND: Cardiac Rubidium-82 (82 Rb) positron emission tomography/computed tomography (PET/CT) provides a measure of the myocardial blood flow and the myocardial flow reserve, which reflects the function of both large epicardial arteries and the myocardial microcirculation. Knowledge on changes in the myocardial microvascular function over time is lacking. METHODS: In this cohort study, we recruited 60 persons with type 2 diabetes and 30 non-diabetic controls, in 2013; all free of overt cardiovascular disease. All underwent a cardiac 82 Rb PET/CT scan. In 2019, all survivors (n = 82) were invited for a repeated cardiac 82 Rb PET/CT scan using the same protocol, and 29 with type 2 diabetes and 19 controls participated. RESULTS: Median duration between visits was 6.2 years (IQR: 6.1-6.3). In the total cohort, the mean age was 66.4 years (SD: 9.3) and 33% were females. The myocardial flow reserve was lower in persons with type 2 diabetes compared to controls (p = 0.002) but there was no temporal change in the myocardial flow reserve in participants with type 2 diabetes: mean change: -0.22 (95% CI: -0.47 to 0.02) nor in controls: -0.12 (-0.49 to 0.25) or when comparing type 2 diabetes to controls: mean difference: -0.10 (95% CI: -0.52 to 0.31). The temporal reduction in stress-induced myocardial blood flow did not differ within the groups but was more pronounced in type 2 diabetes compared to controls: mean difference: -0.30 (95% CI: -0.55 to -0.04). CONCLUSION: The myocardial microvascular function was impaired in persons with type 2 diabetes compared to controls but did not change significantly in either of the groups when evaluated over 6 years.
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Doença da Artéria Coronariana/diagnóstico , Circulação Coronária/fisiologia , Diabetes Mellitus Tipo 2/diagnóstico , Microcirculação/fisiologia , Idoso , Angiografia Coronária/métodos , Doença da Artéria Coronariana/complicações , Doença da Artéria Coronariana/fisiopatologia , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/fisiopatologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Estudos Retrospectivos , Fatores de TempoRESUMO
BACKGROUND: The glycocalyx is an extracellular layer lining the lumen of the vascular endothelium, protecting the endothelium from shear stress and atherosclerosis and contributes to coagulation, immune response and microvascular perfusion. The GlycoCheck system estimates glycocalyx' thickness in vessels under the tongue from perfused boundary region (PBR) and microvascular perfusion (red blood cell (RBC) filling) via a camera and dedicated software. OBJECTIVES: Evaluating reproducibility and influence of examination conditions on measurements with the GlycoCheck system. METHODS: Open, randomised, controlled study including 42 healthy smokers investigating day-to-day, side-of-tongue, inter-investigator variance, intraclass-correlation (ICC) and influence of examination conditions at intervals from 0-180 minutes on PBR and RBC filling. RESULTS: Mean (SD) age was 24.9 (6.1) years, 52% were male. There was no significant intra- or inter-investigator variation for PBR or RBC filling nor for PBR for side-of-tongue. A small day-to-day variance was found for PBR (0.012µm, p = 0.007) and RBC filling (0.003%, p = 0.005) and side-of-tongue, RBC filling (0.025%, p = 0.009). ICC was modest but highly improved by increasing measurements. Small significant influence of cigarette smoking (from 40-180 minutes), high calorie meal intake and coffee consumption was found. The latter two peaking immediately and tapering off but remained significant up to 180 minutes, highest PBR changes for the three being 0.042µm (p<0.05), 0.183µm (p<0.001) and 0.160µm (p<0.05) respectively. CONCLUSIONS: Measurements with the GlycoCheck system have a moderate reproducibility, but highly increases with multiple measurements and a small day-to-day variability. Smoking, meal and coffee intake had effects up to 180 minutes, abstinence is recommended at least 180 minutes before GlycoCheck measurements. Future studies should standardise conditions during measurements.
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Doenças Cardiovasculares/diagnóstico , Técnicas de Diagnóstico Cardiovascular/instrumentação , Endotélio Vascular/diagnóstico por imagem , Microvasos/diagnóstico por imagem , Soalho Bucal/irrigação sanguínea , Adolescente , Adulto , Doenças Cardiovasculares/fisiopatologia , Endotélio Vascular/citologia , Endotélio Vascular/fisiopatologia , Eritrócitos/fisiologia , Feminino , Glicocálix/fisiologia , Humanos , Masculino , Microcirculação/fisiologia , Microvasos/citologia , Microvasos/fisiopatologia , Soalho Bucal/diagnóstico por imagem , Reprodutibilidade dos Testes , Fumantes , Software , Adulto JovemRESUMO
Background: Improved understanding of the pathophysiology causing diabetic kidney disease (DKD) is imperative. The aim of this study was to uncover associations between serum metabolites and renal outcomes. Methods: Non-targeted serum metabolomics analyses were performed in samples from 637 persons with type 1 diabetes using two-dimensional gas chromatography coupled to time-of-flight mass-spectrometry. Longitudinal data at follow-up (median 5.5 years) on renal events were obtained from national Danish health registries. A composite renal endpoint (n = 123) consisted of estimated glomerular filtration rate (eGFR) decline from baseline (≥30%), progression to end-stage renal disease and all-cause mortality. Metabolites with significant associations (p < 0.05) in any of the cross-sectional analyses with eGFR and albuminuria were analyzed for specific and composite endpoints. Adjustments included traditional cardiovascular risk factors and correction for multiple testing. Results: A data-driven partial correlation analysis revealed a dense fabric of co-regulated metabolites and clinical variables dominated by eGFR. Ribonic acid and myo-inositol were inversely associated with eGFR, positively associated with macroalbuminuria (p < 0.02) and longitudinally associated with higher risk of eGFR decline ≥30% (HR 2.2-2.7, CI [1.3-4.3], p < 0.001). Ribonic acid was associated with a combined renal endpoint (HR 1.8, CI [1.3-2.3], p = 0.001). The hydroxy butyrate 3,4-dihydroxybutanoic acid was cross-sectionally associated with micro- and macroalbuminuria, urinary albumin excretion rate and inversely associated with eGFR (p < 0.04) while branched chain amino acids were associated with eGFR and lower risk of the combined renal endpoint (p < 0.02). Conclusions: Alterations in serum metabolites, particularly polyols and amino acids, were associated with renal endpoints in type 1 diabetes highlighting molecular pathways associated with progression of kidney disease. External validation is needed to further assess their roles and potentials as future therapeutic targets.
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BACKGROUND: The number of patients with type 2 diabetes mellitus and diabetes mellitus-associated chronic kidney disease varies considerably between countries. Next to differences in genetic as well as life style risk factors, varying practices in medical care delivery might cause this diversity. METHOD: The PROVALID study recruited 4000 patients with type 2 diabetes mellitus at the primary level of healthcare in five European countries (Austria, Hungary, The Netherlands, Poland and Scotland). Baseline data were used to describe patient characteristics and compare the adherence to ADA (American Diabetes Association) and KDIGO (Kidney Disease: Improving Global Outcomes) guidelines with respect to metabolic and blood pressure control, use of renin-angiotensin system-blocking agents, statins and acetylsalicylic acid between the countries. RESULTS: About 34.8% of the population had evidence of diabetes mellitus-associated chronic kidney disease. The median HbA1c level of the cohort was 6.8% (ranging from 6.5 in Poland to 7.0% in Scotland). Mean blood pressure was 136/79 (±17/10) and significantly higher in subjects with elevated albuminuria. These individuals also were more often treated with renin-angiotensin system-blocking agents (74.1% vs 84.6%), whereas the use of statins was driven by cardiovascular comorbidity. Acetylsalicylic acid was used in only 28.9% subjects. Despite similar cardiovascular comorbidities and renal function, the use of renin-angiotensin system-blocking agents varied significantly between the countries from 66.7% to 87.4%. An even higher variability was observed for patients >40 years of age using statins (39.8%-82.7%) and administration of acetylsalicylic acid in patients older than 50 years (5.2%-43.8%). CONCLUSION: Our study shows that medical practice in type 2 diabetes mellitus patients with and without renal disease is different in European countries. Longitudinal follow-up will reveal if this diversity affects clinical endpoints.
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Diabetes Mellitus Tipo 2/tratamento farmacológico , Nefropatias Diabéticas/tratamento farmacológico , Fidelidade a Diretrizes/tendências , Disparidades em Assistência à Saúde/tendências , Guias de Prática Clínica como Assunto , Padrões de Prática Médica/tendências , Atenção Primária à Saúde/tendências , Insuficiência Renal Crônica/tratamento farmacológico , Idoso , Biomarcadores/sangue , Pressão Sanguínea/efeitos dos fármacos , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/fisiopatologia , Nefropatias Diabéticas/diagnóstico , Nefropatias Diabéticas/epidemiologia , Nefropatias Diabéticas/fisiopatologia , Europa (Continente)/epidemiologia , Feminino , Hemoglobinas Glicadas/metabolismo , Nível de Saúde , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Prospectivos , Insuficiência Renal Crônica/diagnóstico , Insuficiência Renal Crônica/epidemiologia , Insuficiência Renal Crônica/fisiopatologia , Sistema Renina-Angiotensina/efeitos dos fármacos , Fatores de Tempo , Resultado do TratamentoRESUMO
PURPOSE OF REVIEW: We explore how a global shift in the food system caused by global economic growth, increase in available food per capita and in food processing is a driver of the obesity epidemic. RECENT FINDINGS: Economic development in most areas of the world has resulted in increased purchasing power and available per capita food. Supermarkets and a growing fast-food industry have transformed our dietary pattern. Ultra-processed food rich on sugars and saturated fat is now the major source of energy in most countries. The shift in food supply is considered a major driver of the obesity epidemic and the increasing prevalence of accompanying complications, such as type 2 diabetes, cardiovascular disease and cancer. However, the global shift might also have direct effects on the increase in type 2 diabetes, cardiovascular disease and cancer, independently of overweight and obesity. The shift in the food supply is a major driver of the obesity epidemic.
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Desenvolvimento Econômico , Abastecimento de Alimentos , Saúde Global , Obesidade/etiologia , Epidemias , Manipulação de Alimentos , Humanos , Obesidade/epidemiologiaRESUMO
AIMS/HYPOTHESIS: Coronary flow reserve (CFR) and coronary artery calcium (CAC) represent functional and structural aspects of atherosclerosis. We examined the prevalence of reduced CFR and high CAC scores in three predefined groups of participants without known cardiovascular disease: (1) patients with type 2 diabetes and albuminuria; (2) patients with type 2 diabetes and normoalbuminuria; and (3) non-diabetic controls. METHODS: In a cross-sectional design, cardiac (82)Rb positron emission tomography/computed tomography was conducted in 60 patients with type 2 diabetes who were free of overt cardiovascular disease and who were stratified by normoalbuminuria (<30 mg/24 h) (n = 30; age [mean ± SD] 60.9 ± 10.1 years) and albuminuria (≥ 30 mg/24 h) (n = 30; age 65.6 ± 4.8 years), and in 30 healthy, non-diabetic controls (age 59.8 ± 9.9 years). RESULTS: In controls, normoalbuminuric and albuminuric patients, CFR was 3.0 ± 0.8, 2.6 ± 0.8 and 2.0 ± 0.5, respectively. Reduced CFR (<2.5) was observed in 16.7%, 40.0% and 83.3% of participants, respectively, and median (interquartile range) CAC scores were 0 (0-81), 36 (1-325) and 370 (152-1,025), respectively (p for trend <0.01). After adjustment, the difference in CFR and CAC between albuminuric patients and controls remained significant (p ≤ 0.001). There were trends towards lower CFR and higher CAC scores in normoalbuminuric patients vs controls (p ≤ 0.023) and towards higher CAC scores in albuminuric vs normoalbuminuric patients (p = 0.026). In multivariate regression analysis, a higher urinary albumin excretion rate (UAER) tended to predict reduced CFR in the total population (p = 0.045). When the CAC score was added, there was also a trend (p = 0.032) towards an inverse association with reduced CFR. CONCLUSIONS/INTERPRETATION: Type 2 diabetic patients who were free of overt cardiovascular disease had a high prevalence of coronary microvascular dysfunction, especially with concomitant albuminuria, suggesting a common microvascular impairment occurring in multiple microvascular beds. Prospective studies are needed to show the prognostic significance of this finding.
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Diabetes Mellitus Tipo 2/diagnóstico por imagem , Coração/diagnóstico por imagem , Microvasos , Tomografia por Emissão de Pósitrons , Tomografia Computadorizada por Raios X , Adulto , Idoso , Idoso de 80 Anos ou mais , Doenças Assintomáticas , Angiografia Coronária/métodos , Doença da Artéria Coronariana/diagnóstico por imagem , Vasos Coronários/diagnóstico por imagem , Vasos Coronários/patologia , Estudos Transversais , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/fisiopatologia , Feminino , Humanos , Masculino , Microvasos/diagnóstico por imagem , Microvasos/patologia , Microvasos/fisiopatologia , Pessoa de Meia-Idade , Imagem Multimodal/métodos , Radioisótopos de Rubídio , Calcificação Vascular/diagnóstico por imagemRESUMO
Progressive CKD is generally detected at a late stage by a sustained decline in eGFR and/or the presence of significant albuminuria. With the aim of early and improved risk stratification of patients with CKD, we studied urinary peptides in a large cross-sectional multicenter cohort of 1990 individuals, including 522 with follow-up data, using proteome analysis. We validated that a previously established multipeptide urinary biomarker classifier performed significantly better in detecting and predicting progression of CKD than the current clinical standard, urinary albumin. The classifier was also more sensitive for identifying patients with rapidly progressing CKD. Compared with the combination of baseline eGFR and albuminuria (area under the curve [AUC]=0.758), the addition of the multipeptide biomarker classifier significantly improved CKD risk prediction (AUC=0.831) as assessed by the net reclassification index (0.303±-0.065; P<0.001) and integrated discrimination improvement (0.058±0.014; P<0.001). Correlation of individual urinary peptides with CKD stage and progression showed that the peptides that associated with CKD, irrespective of CKD stage or CKD progression, were either fragments of the major circulating proteins, suggesting failure of the glomerular filtration barrier sieving properties, or different collagen fragments, suggesting accumulation of intrarenal extracellular matrix. Furthermore, protein fragments associated with progression of CKD originated mostly from proteins related to inflammation and tissue repair. Results of this study suggest that urinary proteome analysis might significantly improve the current state of the art of CKD detection and outcome prediction and that identification of the urinary peptides allows insight into various ongoing pathophysiologic processes in CKD.
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Peptídeos/urina , Insuficiência Renal Crônica/urina , Adulto , Idoso , Biomarcadores/urina , Estudos de Coortes , Progressão da Doença , Feminino , Taxa de Filtração Glomerular , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
Proteomic profiling by MALDI-TOF MS presents various advantages (speed of analysis, ease of use, relatively low cost, sensitivity, tolerance against detergents and contaminants, and possibility of automation) and is being currently used in many applications (e.g. peptide/protein identification and quantification, biomarker discovery, and imaging MS). Earlier studies by many groups indicated that moderate reproducibility in relative peptide quantification is a major limitation of MALDI-TOF MS. In the present work, we examined and demonstrate a clear effect, in cases apparently random, of sample dilution in complex samples (urine) on the relative quantification of peptides by MALDI-TOF MS. Results indicate that in urine relative abundance of peptides cannot be assessed with confidence based on a single MALDI-TOF MS spectrum. To account for this issue, we developed and propose a novel method of determining the relative abundance of peptides, taking into account that peptides have individual linear quantification ranges in relation to sample dilution. We developed an algorithm that calculates the range of dilutions at which each peptide responds in a linear manner and normalizes the received peptide intensity values accordingly. This concept was successfully applied to a set of urine samples from patients diagnosed with diabetes presenting normoalbuminuria (controls) and macroalbuminuria (cases).
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Peptídeos/urina , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Albuminúria/urina , Sequência de Aminoácidos , Biomarcadores/urina , Diabetes Mellitus Tipo 1/classificação , Diabetes Mellitus Tipo 1/urina , Humanos , Dados de Sequência Molecular , Peptídeos/química , Análise de Regressão , Reprodutibilidade dos TestesRESUMO
BACKGROUND: Previously the angiotensin II receptor blocker Irbesartan has been demonstrated to reduce the risk for progression from microalbuminuria to macroalbuminuria in type 2 diabetic patients. The purpose of this study was to evaluate the effect of treatment with Irbesartan in type 2 diabetic patients with microalbuminuria on the urinary proteome. METHODS: High-resolution capillary-electrophoresis coupled to mass-spectrometry (CE-MS) was used to profile the low-molecular-weight proteome in urine of a subgroup of patients from a two year randomized irbesartan versus placebo therapy trial, which included hypertensive type 2 diabetic patients with microalbuminuria on ongoing antihypertensive medication (IRMA2-substudy). RESULTS: We demonstrate that the therapy with 300 mg Irbesartan daily over a period of two years results in significant changes of the urinary proteome. Both, a classifier developed previously that consists of urinary peptides indicative of chronic kidney disease, as well as several individual peptides changed significantly after treatment. These changes were not observed in the placebo-treated individuals. Most prominent are changes of urinary collagen fragments associated with progression of diabetic nephropathy, indicating normalization in urinary peptides. CONCLUSION: CE-MS analysis of urine enabled identification of peptides as potential surrogate markers for renoprotection in microalbuminuric type 2 diabetic patients, which show persistent improvement after longterm treatment with Irbesartan. The results suggest that a major benefit of treatment by Irbesartan may be improvement of collagen turnover, reduction of fibrosis. They further suggest that urinary proteome analysis could be utilized to assess potential benefit of therapeutic intervention, providing statistically significant results even on a small population.