Hidden sources of phosphorus: presence of phosphorus-containing additives in processed foods.

INTRODUCTION AND OBJECTIVES: An increased consumption of processed foods that include phosphorus-containing additives has led us to propose the following working hypothesis: using phosphate-rich additives that can be easily absorbed in processed foods involves a significant increase in phosphorus in the diet, which may be considered as hidden phosphorus since it is not registered in the food composition tables. MATERIALS AND METHOD: The quantity of phosphorus contained in 118 processed products was determined by spectrophotometry and the results were contrasted with the food composition tables of the Higher Education Centre of Nutrition and Diet, those of Morandeira and those of the BEDCA (Spanish Food Composition Database) Network. RESULTS: Food processing frequently involves the use of phosphoric additives. The products whose label contains these additives have higher phosphorus content and higher phosphorus-protein ratio. We observed a discrepancy with the food composition tables in terms of the amount of phosphorus determined in a sizeable proportion of the products. The phosphorus content of prepared refrigerated foods hardly appears in the tables. CONCLUSIONS: Product labels provide little information on phosphorus content. We observed a discrepancy in phosphorus content in certain foods with respect to the food composition tables. We should educate our patients on reviewing the additives on the labels and on the limitation of processed foods. There must be health policy actions to deal with the problem: companies should analyse the phosphorus content of their products, display the correct information on their labels and incorporate it into the food composition tables. Incentives could be established to prepare food with a low phosphorus content and alternatives to phosphorus-containing additives.

The impact of processing meat and fish products on phosphorus intake in chronic kidney disease patients.

INTRODUCTION AND OBJECTIVES: The use of phosphate additives in meat and fish processing leads to a phosphorus overload that we cannot quantify through labelling or food composition tables. We analysed this increase by measuring phosphorus content in these products by spectrophotometry. MATERIALS AND METHOD: We determined the phosphorus/protein ratio in fresh meat and fish products with varying degrees of processing by spectrophotometry (phosphorus) and the Kjeldahl method (proteins). We contrasted these results with those reflected in the food composition tables. RESULTS: The phosphorus/protein ratio was higher in processed meat products (15.83 mg/g) than in battered (11.04 mg/g) and frozen meat products (10.5mg/g), and was lower in fresh (8.41 mg/g) and refrigerated meat products (8.78 mg/g). Fresh white fish had a phosphorus/protein ratio of 8.58mg/g, while it increased by 22% (10.3mg/g) in frozen white fish and by 46% (12.54 mg/g) in battered fish. The information in the tables was poor and confusing, and no reference is made to the brands tested. CONCLUSIONS: Processing meat and fish products poses a serious obstacle to the reduction of phosphorus intake. The current regulatory framework does not assist us in the objective of reducing phosphorus additives, since it considers them safe for public consumption. Overcoming these barriers requires a coordinated effort to demonstrate that a high intake of these additives may be harmful to the general population and it should be more closely examined by regulators.

First episodes of peritoneal infection: description and prognostic factors.

INTRODUCTION: Peritonitis is one of the most common and severe complications associated with peritoneal dialysis (PD), constituting the primary cause of catheter loss and exit from the dialysis technique. The incidence and aetiology of peritonitis episodes vary based on geographical region, and change over time. For this reason, it is vital to maintain an updated understanding of the current risk factors and prognostic factors associated with peritonitis. METHOD: We performed an observational, multi-centre, prospective cohort study with a maximum follow-up period of 7 years (2003-2010), which included 1177 patients and a total of 476 first episodes of peritonitis (total: 1091 cases of peritonitis). RESULTS: We describe the characteristics of the first episode of peritonitis from a large and current study sample. The factors associated with a shorter interval until the first episode of peritonitis as selected by the multivariate analysis included prior cardiovascular comorbidity (Hazard Ratio [HR]: 1.25 [1.04-1.58]), having previously received haemodialysis (HR: 1.39 [1.10-1.76]) or a kidney transplant (HR: 1.38 [1.10-1.93]), having started PD on a manual modality (HR: 1.39 [1.13-1.73]), and initial age >70 years (HR: 1.53 [1.23-1.90]). The first episode of peritonitis was associated with a 7.8% rate of recurrence, an 11.7% rate of catheter removal, and a mortality rate within one month of the episode of 1.3%. The progression of peritonitis infections depended on the type of causal microorganism. We calculated a greater risk for gram-negative bacterial infections (Odds Ratio [OR]: 5.31 [2.26-12.48]) and the aggregate group of infections caused by multiple microorganisms, fungal infections, and mycobacterial infections (OR: 38.24 [13.84-105.63]), as compared to gram-positive bacterial infections. CONCLUSION: The development of a first case of peritonitis depends on the characteristics of the patient upon starting dialysis, comorbidities present, and the technique used. Patients at a greater risk for peritonitis must receive special care during training and follow-up.

[Microalbuminuria accounts for the increased vascular disease risk in diabetic patients with metabolic syndrome]. / La microalbuminuria explica el incremento de riesgo vascular en pacientes con diabetes y síndrome metabólico.

The aim of this study was to determine the impact of the metabolic syndrome on vascular disease risk in patients with type-2 diabetes. A prospective cohort study was carried out. The main dependent variable was the combination of coronary disease, stroke and lower leg amputation. Cox regression modeling was used. In total, 317 patients were followed for a mean of 7.7 years. The prevalence of metabolic syndrome was 87%. Multivariate analysis identified the following as predictors of incident vascular disease: age (relative risk [RR] =1.06, 95% confidence interval [CI], 1.02-1.1; P=.0003), baseline cardiovascular disease (RR=1.8; 95% CI, 1.1-3.0; P=.017), and the simultaneous presence of four metabolic risk factors (RR=5.8; 95% CI, 1.8-18; P=.003). The most predictive factor was microalbuminuria (chi2=5.9; P=.015). Microalbuminuria accounts for the increased risk of vascular disease in patients with metabolic syndrome. In evaluating vascular disease risk in patients with type-2 diabetes, it is more important to consider the total number of metabolic risk factors than the presence of metabolic syndrome alone.

La microalbuminuria explica el incremento de riesgo vascular en pacientes con diabetes y síndrome metabólico / Microalbuminuria accounts for the increased vascular disease risk in diabetic patients with metabolic syndrome

El objetivo fue evaluar la importancia pronóstica del síndrome metabólico (SM) en el riesgo vascular en diabetes mellitus tipo 2 (DM2). Se realizó estudio de cohortes prospectivo. La variable dependiente, enfermedad cardiovascular (ECV), fue una combinación de eventos coronarios, cerebrovasculares y amputación de extremidades inferiores. Se utilizó modelo de regresión de Cox. Se incluyó a 317 pacientes seguidos durante 7,7 años. La prevalencia de SM fue del 87%. Los predictores de ECV incidente en análisis multivariable fueron: edad (riesgo relativo [RR] = 1,06; intervalo de confianza [IC] del 95%, 1,02-1,1; p = 0,0003), ECV prevalente (RR = 1,8; IC del 95%, 1,1-3; p = 0,017), y presentar simultáneamente 4 factores de riesgo metabólicos (RR = 5,8; IC del 95%, 1,8-18; p = 0,003). El componente más predictivo fue la microalbuminuria (χ2 = 5,9; p = 0,015). La microalbuminuria explica el poder predictivo del SM para la aparición de ECV. Es más importante considerar el número de factores de riesgo metabólico que el SM al evaluar el riesgo vascular del paciente con DM2 (AU)

The aim of this study was to determine the impact of the metabolic syndrome on vascular disease risk in patients with type-2 diabetes. A prospective cohort study was carried out. The main dependent variable was the combination of coronary disease, stroke and lower leg amputation. Cox regression modeling was used. In total, 317 patients were followed for a mean of 7.7 years. The prevalence of metabolic syndrome was 87%. Multivariate analysis identified the following as predictors of incident vascular disease: age (relative risk [RR] =1.06, 95% confidence interval [CI], 1.02-1.1; P=.0003), baseline cardiovascular disease (RR=1.8; 95% CI, 1.1-3.0; P=.017), and the simultaneous presence of four metabolic risk factors (RR=5.8; 95% CI, 1.8-18; P=.003). The most predictive factor was microalbuminuria (χ2=5.9; P=.015). Microalbuminuria accounts for the increased risk of vascular disease in patients with metabolic syndrome. In evaluating vascular disease risk in patients with type-2 diabetes, it is more important to consider the total number of metabolic risk factors than the presence of metabolic syndrome alone (AU)

[Diabetic retinopathy and mortality in type 2 diabetic patients]. / Relación entre la presencia de retinopatía diabética y la mortalidad en pacientes con diabetes tipo 2.

BACKGROUND AND OBJECTIVE: This study was intended to assess the independent contribution of retinopathy to mortality in type 2 diabetic patients. PATIENTS AND METHOD: Prospective cohort study. Type 2 diabetic patients with available fundus were included. The clinical end-point was total mortality. The main independent variable was baseline presence of background or proliferative retinopathy. Cox regression models were adjusted for age, sex, duration of diabetes, classical risk factors and baseline presence of nephropathy and cardiovascular disease. RESULTS: 458 patients were included (181 male, 277 females), with a median follow-up of 8 years (inter-quartile range, 6.7-9). There were 125 patients (27.3%) with background retinopathy and 46 (10%) with proliferative retinopathy. Mortality incidence rates per 1,000 patients-year were 20/1,000 (non retinopathy), 36.8/1,000 (background retinopathy) and 45.9/1,000 (proliferative retinopathy) with p = 0.0021. In the multivariate analysis, background retinopathy (HR = 1.87; 95% CI, 1.1-3.1; p = 0.019) and proliferative retinopathy (HR = 2.6; 95% CI, 1.3-5.1; p = 0.0048) were independent predictors of mortality. Other independent predictors were age (HR [1 year] = 1.13; 95% CI, 1.1-1.17; p < 0.0001), total cholesterol (HR [1 mmol/l] = 0.76; 95% CI, 0.6-0.97; p = 0.026), baseline insulin treatment (HR = 1.9; 95% CI, 1,1-3.2; p = 0.017) and baseline proteinuria (HR = 4.1; 95% CI, 2-8.5; p = 0.0001). CONCLUSIONS: The presence of retinopathy increases the mortality risk in type 2 diabetic patients.

Relación entre la presencia de retinopatía diabética y la mortalidad en pacientes con diabetes tipo 2 / Diabetic retinopathy and mortality in type 2 diabetic patients

Fundamento y objetivo: Evaluar la contribución independiente de la retinopatía diabética a la mortalidad de los pacientes con diabetes tipo 2. Pacientes y método: Estudio de cohortes prospectivo. Se incluyó a los pacientes con diabetes tipo 2 y fondo de ojo visualizable. Como variable dependiente, se evaluó la mortalidad total. La variable independiente principal fue la presencia de retinopatía simple o proliferativa, con ajuste para edad, sexo, tiempo de evolución de la diabetes, factores de riesgo clásicos y presencia de otras complicaciones crónicas (nefropatía y macroangiopatía). Se realizaron curvas de supervivencia y regresión de Cox multivariable, con cálculo de cocientes de riesgo (CR). Resultados: Se incluyó a 458 pacientes (181 varones y 277 mujeres), con seguimiento mediano de 8 años (intervalo intercuartil, 6,7-9). Hubo 125 (27,3%) pacientes con retinopatía simple y 46 (10%) con proliferativa. Las tasas de incidencia de mortalidad fueron 20/1.000 pacientes-año (ausencia de retinopatía), 36,8/1.000 pacientes-año (retinopatía simple) y 45,9/1.000 pacientes-año (retinopatía proliferativa); p = 0,0021. En el análisis multivariable, la presencia de retinopatía simple (CR = 1,87; intervalo de confianza [IC] del 95%, 1,1-3,1; p = 0,019) y de retinopatía proliferativa (CR = 2,6; IC del 95%, 1,3-5,1; p = 0,0048) predijeron de modo independiente la mortalidad. Otros predictores independientes fueron la edad (CR [1 año] = 1,13; IC del 95%, 1,1-1,17; p < 0,0001), el colesterol total (CR [1 mmol/l] = 0,76; IC del 95%, 0,6-0,97; p = 0,026), el tratamiento con insulina (CR = 1,9; IC del 95%, 1,1-3,2; p = 0,017) y la proteinuria (CR = 4,1; IC del 95%, 2-8,5; p = 0,0001). Conclusiones: La presencia de retinopatía diabética se relaciona con un incremento de mortalidad en los pacientes con diabetes tipo 2

Background and objective: This study was intended to assess the independent contribution of retinopathy to mortality in type 2 diabetic patients. Patients and method: Prospective cohort study. Type 2 diabetic patients with available fundus were included. The clinical end-point was total mortality. The main independent variable was baseline presence of background or proliferative retinopathy. Cox regression models were adjusted for age, sex, duration of diabetes, classical risk factors and baseline presence of nephropathy and cardiovascular disease. Results: 458 patients were included (181 male, 277 females), with a median follow-up of 8 years (inter-cuartile range, 6.7-9). There were 125 patients (27.3%) with background retinopathy and 46 (10%) with proliferative retinopathy. Mortality incidence rates per 1,000 patients-year were 20/1,000 (non retinopathy), 36.8/1,000 (background retinopathy) and 45.9/1,000 (proliferative retinopathy) with p = 0.0021. In the multivariate analysis, background retinopathy (HR = 1.87; 95% CI, 1.1-3.1; p = 0.019) and proliferative retinopathy (HR = 2.6; 95% CI, 1.3-5.1; p = 0.0048) were independent predictors of mortality. Other independent predictors were age (HR [1 year] = 1.13; 95% CI, 1.1-1.17; p < 0.0001), total cholesterol (HR [1 mmol/l] = 0.76; 95% CI, 0.6-0.97; p = 0.026), baseline insulin treatment (HR = 1.9; 95% CI, 1,1-3.2; p = 0.017) and baseline proteinuria (HR = 4.1; 95% CI, 2-8.5; p = 0.0001). Conclusions: The presence of retinopathy increases the mortality risk in type 2 diabetic patients

Microalbuminuria presents the same vascular risk as overt CVD in type 2 diabetes.

OBJECTIVES: We attempted to assess whether microalbuminuria conferred the same cardiovascular risk as overt CVD in type 2 diabetic patients. MATERIAL AND METHODS: A prospective cohort study including 436 type 2 diabetic patients (64.8+/-9.2 years old) without proteinuria, with follow-up until any cardiovascular event occurred, was performed. Patients were classified into four groups: group 0, non baseline CVD and normoalbuminuria; group 1, non baseline CVD and microalbuminuria; group 2, baseline CVD and normoalbuminuria; group 3, baseline CVD and microalbuminuria. Cox's multivariate regression models were used to assess the risk ratio (RR) associated with each variable. RESULTS: The median follow-up time was 7.6 years. Incidence rates of cardiovascular events per 1000 patient-years increased from groups 0 to 3 (23.8, 63.4, 74.1, 85.6; p<0.0001). Multivariate RR for incident CVD in groups 1, 2 and 3 in relation to group 0 were 2.8 (95% confidence interval (CI) 1.7-4.6; p<0.0001), 2.7 (95% CI 1.6-4.6; p<0.0001) and 2.9 (95% CI 1.6-5.4; p=0.001), respectively. No significant differences were seen between groups 1 and 2. CONCLUSIONS: We suggest that patients with microalbuminuria are at very high vascular risk and should share the same objectives of a vascular risk-factor control as patients with overt CVD.

[Metabolic syndrome as a cardiovascular risk factor in patients with type 2 diabetes]. / Influencia del sídrome metabólico en el cardiovascular de pacientes con diabetes tipo 2.

INTRODUCTION AND OBJECTIVES: To assess the cardiovascular risk associated with the presence of metabolic syndrome in patients with type 2 diabetes. Patients and method. Prospective cohort study of patients with type 2 diabetes. The baseline presence of components of metabolic syndrome as defined by the World Health Organization was determined. The main dependent variable was a combination of coronary events (onset angina, fatal or nonfatal myocardial infarction) and cerebrovascular events (transient ischemic attack, fatal or nonfatal stroke and lower limb amputation). Secondary end points were coronary events and stroke. We calculated the predictive power of the presence of metabolic syndrome and of different numbers of its component features. RESULTS: 318 patients were included. Mean duration of follow-up was 4.6 years (SD 1.5 years). The prevalence of metabolic syndrome was 77.0%. The rates of cardiovascular events, coronary events and stroke, expressed per 1000 patient-years, were 14.0, 5.6, and 8.4 respectively in patients without metabolic syndrome, and 33.3, 20.7, and 11.7 respectively in patients with metabolic syndrome (P=.058 cardiovascular events; P=.05 coronary events). In the multivariate analysis, the simultaneous presence of all four metabolic syndrome components significantly increased the global cardiovascular disease risk (RR=5.0; 95% CI, 1.6-15.9; P=.006) and the risk of coronary heart disease (RR=7.4; 95% CI, 1.3-41.1; P=.02), but not the risk of stroke. CONCLUSIONS: The simultaneous presence of all four metabolic syndrome components is associated with an increase in the risk of cardiovascular events in patients with type 2 diabetes.

Mild renal insufficiency as a cardiovascular risk factor in non-proteinuric type II diabetes.

OBJECTIVES: To evaluate cardiovascular risk according to baseline renal function in a group of non-proteinuric type II diabetic patients. MATERIAL AND METHODS: Prospective study with a follow-up of 423 non-proteinuric type II diabetic patients with creatinine <150 micromol/l for an average of 4.7 years (S.D. 1.55). Creatinine clearance (CC) was estimated using the Cockcroft-Gault formula and expressed in millilitre per minute. The hazard ratio (HR) associated with each millilitre per minute decrease in baseline CC on fatal or non-fatal cardiovascular events and total mortality was evaluated using the Cox regression model. RESULTS: Baseline creatinine was 89 micromol/l (S.D. 15.9) and CC was 69.5 ml/min (S.D. 20). There were 63 cardiovascular events (15 unstable angina, 10 non-fatal myocardial infarctions, 25 non-fatal strokes, two amputations, nine fatal myocardial infarctions and two fatal strokes) and 39 total deaths (11 for cardiovascular causes). The cardiovascular event rate was 31.7/1000 patient-years and the total mortality rate was 19.6/1000 patient-years. The independent predictors of cardiovascular events were: CC (HR=1.035; confidence interval (CI) 95% 1.02-1.05; P<0.0001), total cholesterol/HDL cholesterol ratio (HR=1.25; CI 95% 1.1-1.4; P=0.0008), baseline coronary heart disease (HR=2.05; CI 95% 1.07-3.9; P=0.04) and baseline microalbuminuria (HR=2.3; CI 95% 1.3-3.8; P=0.003). The independent total mortality predictors were: CC (HR=1.04; CI 95% 1.02-1.08; P<0.0001), male (HR=2.1; CI 95% 1.1-4; P=0.027) and baseline microalbuminuria (HR=2.1; CI 95% 1.1-4;P=0.03). CONCLUSIONS: Mild renal insufficiency increases cardiovascular risk in non-proteinuric patients with type II diabetes.

Fasting plasma glucose variability as a risk factor of retinopathy in Type 2 diabetic patients.

AIMS/HYPOTHESIS: The purpose of this study was to determine whether plasma glucose variability, irrespective of glycated hemoglobin (HbA1c), was able to predict the onset of retinopathy in Type 2 diabetic patients. METHODS: The study was based on a cohort of 130 Type 2 diabetic patients without retinopathy recruited from June 1994 to June 1998. The fundus was reexamined between November 2000 and June 2001, with a mean follow-up period of 5.2 years. Fasting plasma glucose (FPG) variability was measured by its variation coefficient (VC). Stratified and multivariate models were used to estimate the effect of FPG variability and mean HbA1c during follow-up on cumulative incidence (IP) of retinopathy. RESULTS: The IP of retinopathy was 36.2% and increased all along the quartiles of FPG variability (P=.001). In multivariate analyses, only the last quartile of the distribution of VC (OR=3.68; 95% confidence interval (CI) 1.01-13.4; P=.049) was significant. The term of interaction between mean HbA1c and VC was not significant. CONCLUSIONS/INTERPRETATION: FPG variability fulfills criteria to be considered a risk factor for retinopathy: A statistically significant association exists after adjustment for confounders, time sequence, dosage response gradient, and biological plausibility.