MO522BIOMARKERS OF KIDNEY FUNCTION AS POTENTIAL PROGNOSTIC FACTORS FOR CARDIOVASCULAR DISEASE IN TYPE 2 DIABETIC PATIENTS

Background and Aims

Developing risk predictive models in high-risk populations, such as patients with type 2 diabetes (T2DM), might provide an individualized risk prediction. During the past decade, the studies assessing carotid intima media thickness (cIMT) as a novel risk factor for cardiovascular (CV) disease, produced controversial results. In this study, we assessed the prognostic value of various risk factors, including cIMT and biomarkers of kidney function, to predict incident CV events in T2DM patients.

Method

A total of 158 adults, with a history of type 2 diabetes for>10 years were recruited. At baseline, urinary albumin to creatinine ratio (UACR), eGFR and cIMT were evaluated. All patients were followed for a period of 7 years with fatal or nonfatal CV events as the primary endpoint. By adopting the Fine and Gray model, which takes into account the competitive risk of death, we assessed the associations between CV events and various candidate prognostic factors collected at baseline.

In multiple Cox Fine and Gray models, we included all variables that were correlated with the study outcome in univariate analysis, (full model with 9 variables). The prognostic performance of the full model was compared with that of a simpler (nested) model based only on three prognostic variables (simplified model).

To compare the data fitting of the 2 models, we used −2 log likelihood (−2 log L) statistics. The calibration and the discrimination abilities of both models were assessed by Hosmer-Lemeshow test and by receiver operating characteristic (ROC) curve, respectively.

Results

During the follow-up period (median 57.5 months, range 7–84 months), 75 patients experienced CV events (33 fatal, 42 nonfatal), and 13 died of causes other than CV. In univariate competitive risk analysis, hemoglobin (SHR 0.85, 95% CI 0.74–0.98, P = 0.02), female sex (SHR 0.50, 95% CI 0.30–0.82, P = 0.006), eGFR (SHR 0.98, 95% CI 0.97–0.99, P <0.0001), serum albumin (SHR 0.43, 95% CI 0.26–0.74, P = 0.002), and HDL cholesterol (SHR 0.97, 95% CI 0.95–0.99, P = 0.02) were inversely associated with the incident rate of CV events, whereas the duration of type 2 diabetes (SHR 1.03, 95% CI 1.00–1.06, P = 0.04), background CVD (SHR 5.47, 95% CI 2.45–12.23, P <0.0001), UACR (SHR 1.01, 95% CI 1.00–1.01, P <0.0001), and cIMT (SHR 7.45, 95% CI 3.46–16.04, P <0.0001) were directly related to the same endpoint. In a multivariate Fine and Gray model including all 9 univariate correlates of CV events (full model), only history of CVD (SHR 5.86, 95% CI 2.15–13.36, P <0.0001), eGFR (SHR 0.99, 95% CI 0.98–0.99, P = 0.009), UACR (SHR 1.01, 95% CI 1.00–1.01, P <0.0001), and cIMT (SHR 3.92, 95% CI 1.24–12.35, P = 0.02) remained significantly associated to the study outcome. In the simplified model only history of CVD (SHR 6.47, 95% CI 2.69–15.55, P <0.0001), UACR (SHR 1.01, 95% CI 1.00–1.01, P <0.0001), and eGFR (SHR 0.98, 95% CI 0.97–0.99, P <0.0001) maintained an independent relationship with CV outcomes.

The data fitting of the two models did not significantly differ (χ2 = 9.48, 6 Df, P = 0.15) and the assessment of the areas under the ROC curves (Figure 1) confirmed that the two models had almost identical accuracy to predict the study outcome (full model 87%, 95% CI 0.81–0.92, P <0.001, simplified model 84%, 95% CI 0.78–0.90, P <0.001). Moreover, the Hosmer-Lemeshow test showed that the simplified model was better calibrated than the full model, because the P value of this test in the simplified model is farther from statistical significance (χ2 = 9.24, P = 0.32) than that of the full model (χ2 = 11.09, P = 0.20).

Conclusion

We propose a simple model for CV event prediction that includes only three easy-to-measure variables. eGFR, albuminuria, and history of CVD can be used for prognosis of CVD, whereas cIMT adds little to the accuracy of this prediction.

MO627ASSOCIATION OF OXIDIZED LDL CHOLESTEROL WITH MORTALITY AND PROGRESSION OF PROTEINURIC DIABETIC KIDNEY DISEASE

Background and Aims

Oxidative modification of low-density lipoprotein (oxLDL) contributes to the pathogenesis and progression of oxidative stress (OS) and atherosclerosis in both Type 2 Diabetes Mellitus (T2DM) and Chronic Kidney Disease (CKD). Compared to normo-and micro-albuminuric, T2DM patients with macroalbuminuria have significantly higher plasma oxLDL levels. In this study we aimed to assess the possible predictive role of oxLDL for mortality and deterioration of renal function in a cohort of patients with proteinuric diabetic CKD.

Method

91 patients with diabetic retinopathy, persistent proteinuria and eGFR below 90ml/min were recruited. At baseline, oxLDL, proteinuria and eGFR were assessed and patients were categorized according to median oxLDL (above or below 66.22 U/L). All patients were prospectively followed for a period of 10 years or the occurrence of a combined outcome of mortality or at least 30% decline in eGFR and/or progression to end stage renal disease (ESRD), requiring renal replacement therapy. At the end of the follow-up period, renal function was re-assessed with a new estimation of eGFR, using the CKD-EPI formula. We performed a statistical analysis with receiver operation curves (ROC) to further examine the possible effect of oxLDL on the percentage change in eGFR and proteinuria over time (calculated as ΔeGFR/baseline eGFR and Δproteinuria/baseline proteinuria respectively) and divided by the follow-up time.

Results

The mean age of the patients was 67.02±8.2 years, and the mean duration of T2DM was 14.5±8.0 years. At baseline, compared to the low, patients with high circulating oxLDL levels had significantly higher levels of triglycerides, higher diastolic blood pressure and lower eGFR (P=0.001, P=0.04 and P-0.013, respectively, Mann-Whitney test). After a 10-year follow up, 10/46 patients in the low and 20/45 patients in the high ox-LDL group presented the composite outcome. Kaplan-Meier curves (Figure 1) showed that patients with oxLDL levels above median (>66.22 U/L) presented a significantly higher risk for the outcome compared to the low oxLDL group (P=0.001, log-rank test). Univariate Cox proportional hazard analysis revealed that high circulating oxLDL levels were independent predictors of the composite endpoint (HR=3.42, 95%CI: 1.55-7.56, P=0.002). After adjustment for all factors that were associated with the outcome in univariate models (baseline proteinuria, serum albumin, duration of T2DM and triglycerides), multivariate Cox analysis showed that the association between high oxLDL levels and the study endpoint remained significant (HR=3.76, 95%CI: 1.52-9.27, P=0.004). At ROC analysis the area under the curve (AUC) for oxLDL to identifying progressor patients was 0.68 (95% CI: 0.56-0.80, P=0.005). Of note, this AUC was virtually identical to that of baseline proteinuria. OxLDL failed to show any association with the change of proteinuria over time.

Conclusion

Circulating ox-LDL might play an important role in the progression of proteinuric DKD.

Oxidized LDL Modifies the Association between Proteinuria and Deterioration of Kidney Function in Proteinuric Diabetic Kidney Disease

Proteinuria is characterized by low accuracy for predicting onset and development of diabetic kidney disease (DKD) because it is not directly associated with molecular changes that promote DKD, but is a result of kidney damage. Oxidized low-density lipoprotein (ox-LDL) reflects oxidative stress and endothelial dysfunction, both underlying the development of proteinuria and loss of kidney function in DKD. We aimed to investigate whether ox-LDL modifies the association between proteinuria and progression of DKD in a cohort of 91 patients with proteinuric DKD and diabetic retinopathy, followed for 10 years. The primary endpoint was a combined kidney outcome of eGFR decline ≥30% or progression to end-stage kidney disease. After the end of the study, we considered the percentage change of eGFR over time as our secondary outcome. Proteinuria was associated with both outcomes, and ox-LDL amplified the magnitude of this link (p < 0.0001 for primary and p < 0.0001 for secondary outcome, respectively). After adjustment for duration of diabetes, history of cardiovascular disease and serum albumin, ox-LDL remained a significant effect modifier of the association between proteinuria and eGFR decline over time (p = 0.04). Our study shows that in proteinuric DKD, circulating ox-LDL levels amplified the magnitude of the association between proteinuria and progression of DKD.

Prognostic Factors of Fatal and Nonfatal Cardiovascular Events in Patients With Type 2 Diabetes: The Role of Renal Function Biomarkers

In this study, 158 patients with different degrees of renal function were followed for 7 years to assess the prognostic value of various risk factors, including carotid intima-media thickness (cIMT) and biomarkers of renal function, for incident cardiovascular morbidity and mortality in patients with type 2 diabetes. The investigators found that estimated glomerular filtration rate, albuminuria, and history of cardiovascular disease (CVD) can be used for prognosis of CVD, whereas cIMT adds little to the accuracy of this prediction.

The Association of dp-ucMGP with Cardiovascular Morbidity and Decreased Renal Function in Diabetic Chronic Kidney Disease

We aimed to investigate the possible association of the inactive, dephosphorylated, uncarboxylated matrix Gla protein (dp-ucMGP) with oxidized low-density lipoprotein (ox-LDL) and all-cause/cardiovascular (CV) mortality and renal function in diabetic chronic kidney disease (CKD). Ox-LDL and dp-ucMGP were determined in 66 diabetic CKD patients. All patients were prospectively followed for seven years, or until the occurrence of death, or a composite renal outcome of 30% estimated glomerular filtration rate (eGFR) reduction or progression to end-stage renal disease (ESRD) requiring dialysis occurred. Secondary outcomes were the occurrence of CV events. Kaplan-Meier curves showed that patients with plasma dp-ucMGP levels above the median (≥656 pM) had a significantly higher risk for all study endpoints. After adjustment for several well-known cofounders, multivariate Cox analysis showed that high plasma dp-ucMGP levels were associated with all-cause mortality (Hazard ratio-HR = 2.63, 95% Confidence Interval-CI = 1.17-5.94, p = 0.02), CV mortality (HR = 2.82, 95% CI = 1.07-7.49, p = 0.037) and progression of CKD (HR = 4.02, 95% CI = 1.20-13.46, p = 0.024). Circulating dp-ucMGP is associated with mortality and decreased renal function in diabetic CKD.

Determination of environmental flows in rivers using an integrated hydrological-hydrodynamic-habitat modelling approach

We propose the novel integrated modelling procedure 3H-EMC for the determination of the environmental flow in rivers and streams; 3H-EMC combines Hydrological, Hydrodynamic and Habitat modelling with the use of the Environmental Management Classes (EMCs) that are defined by the Global Environmental Flow Calculator. We apply 3H-EMC in the Sperchios River in Central Greece, in which water abstractions for irrigation cause significant environmental impacts. Calculations of the hydrodynamic-habitat model, in which the large and the small chub are the main fish species, suggest discharge values that range from 1.0 m³/s to 4.0 m³/s. However, hydrological modelling indicates that it is practically difficult to achieve discharges that are higher than approximately 1.0-1.5 m³/s. Furthermore, legislation suggests significantly lower values (0.4-0.5 m³/s) that are unacceptable from the ecological point of view. This behaviour shows that a non-integrated approach, which is based only on hydrodynamic-habitat modelling does not necessarily result in realistic environmental flows, and thus an integrated approach is required. We propose the value of 1.0 m³/s as the "optimum" environmental flow for Sperchios River, because (a) it satisfies the habitat requirements, as expressed by the values of weighted useable area that are equal to 2180 and 1964 m² for the large and small chub, respectively, and correspond to 82 and 95% of their respective maximum values, (b) it is consistent with the requirements of Environmental Classes A and B, whose percentiles are higher than 75% for discharge (77.2%) and for habitat availability (>83.5% for the large chub and >85.0% for the small chub), (c) it is practically achievable from the hydrological point of view, and (d) it is higher than the value proposed by the Greek legislation. The proposed modelling approach can be applied to any river or stream using the same or similar modelling tools, which should be linked via suitable coupling algorithms.

Quantifying the bystander-effect of 2.5G mobile telephones on the speech perception of digital hearing aid users

OBJECTIVE

To quantify the bystander-effect of 2.5G mobile telephones (2.5G-MTs) on the speech perception of digital hearing-aid (dHA) users. Differences in the susceptibility of behind-the-ear (BTE) compared to in-to-the-ear (ITE) dHAs were also assessed.

MATERIALS/METHODS

Prospective-comparative study conducted at a tertiary referral centre (ENT Department) and a HA-fitting laboratory. Key-word recognition scores from open-sentence lists were calculated. Power-analysis determined that a minimum of 60 subjects with SNHL (30 in each group), using either BTE or ITE dHAs, were required for reliable study outcomes. Sixty-four adults were tested with a functioning 2.5G-MT at almost physical contact with their ear; thirty subjects used BTE and 34 ITE dHAs.

MAIN OUTCOME MEASURES

Aided word recognition score differences between studied groups and within each group, while a 2.5G-MT was activated. Cut-off inclusion criterion regarding baseline aided word recognition score was 75%.

RESULTS

Baseline aided word recognition scores for ITE dHAs were better compared to BTE ones (p < 0.01). Following the 2.5G-MT activation, this difference disappeared. No statistically significant difference in word recognition was observed between the examined groups, or within the BTE group, from the bystander-effect of the 2.5G-MT. ITE dHAs proved more susceptible to electromagnetic interference (p < 0.05).

CONCLUSION

The bystander-effect of 2.5G-MTs on the speech perception of dHA users is either minimal, or not significant. The observed compatibility has a positive impact on the lives of millions of people worldwide. The long-standing theory of more interference in BTE compared to ITE HAs is not confirmed by the results of the present study. EBM level of evidence: 2c.

Psychometric properties of the QLQ-C30 (version 3.0) in a sample of ambulatory Cretan cancer patients

The aim of the present study was to test the psychometric properties of the Quality of Life Questionnaire (QLQ-C30, version 3.0) in a sample of ambulatory cancer patients, mostly low educated and coming from rural areas of the island of Crete. The sample consisted of 188 lung, breast and colorectal cancer patients. Their quality of life (QoL) has been evaluated twice: before and after the first therapeutic intervention. Alpha coefficients ranged from 0.88 to 0.98. Inter-scale correlations were more substantial between the physical, role and fatigue scales. Mean score differences between groups of patients with different performance status (PS) were statistically significant for most of the sub-scales. Instead the patients with stable PS after treatment showed worse functioning in five from the nine sub-scales. For those whose PS has deteriorated, their subjective evaluation indicated deterioration only for physical, role and social functioning. In this sample of mainly ambulatory cancer patients, the instrument has high coefficients of reliability and good clinical validity. However, the results related to its sensitivity are not very consistent. It has proven able to detect clinically significant changes after the therapeutic intervention only for the patients who deteriorated over time and for three specific dimensions of QoL: physical, role and social functioning.