Sodium intake and blood pressure in renal transplant recipients

Background - Hypertension is common among renal transplant recipients (RTR) and a risk factor for graft failure and mortality. Sodium intake is a well-established determinant of blood pressure (BP) in the general population. However, data in RTR are limited. International guidelines recommend a maximum daily sodium intake of 70 mmol. We investigated sodium intake in RTR as compared to healthy controls and its association with BP. Methods - We included 660 RTR (age 53 ± 13 years, 58% male) and 201 healthy controls (age 54 ± 11 years, 46% male). Sodium intake was assessed from 24-h urine collections. The morning after completion of urine collection, BP was measured according to a strict protocol. Results. Urinary sodium excretion was 156 ± 62 mmol/24 h in RTR and 195 ± 75 in controls (difference: P 70 mmol/24 h. Systolic BP (SBP) and diastolic BP (DBP) were 136 ± 18 and 82 ± 11 mmHg, respectively. Sodium intake was positively associated with SBP (ß = 0.042 mmHg/mmol/24 h, P = 0.002) and DBP (ß = 0.023 mmHg/mmol/24 h, P = 0.007), independent of potential confounders. Conclusions - Although RTR had a lower sodium intake than healthy controls, their intake still exceeded current guidelines. Reduction of sodium intake to recommended amounts could reduce SBP by 4–5 mmHg. Better control of sodium intake may help to prevent graft failure and mortality due to hypertension among RTR

Sodium intake and blood pressure in renal transplant recipients

Background - Hypertension is common among renal transplant recipients (RTR) and a risk factor for graft failure and mortality. Sodium intake is a well-established determinant of blood pressure (BP) in the general population. However, data in RTR are limited. International guidelines recommend a maximum daily sodium intake of 70 mmol. We investigated sodium intake in RTR as compared to healthy controls and its association with BP. Methods - We included 660 RTR (age 53 ± 13 years, 58% male) and 201 healthy controls (age 54 ± 11 years, 46% male). Sodium intake was assessed from 24-h urine collections. The morning after completion of urine collection, BP was measured according to a strict protocol. Results. Urinary sodium excretion was 156 ± 62 mmol/24 h in RTR and 195 ± 75 in controls (difference: P 70 mmol/24 h. Systolic BP (SBP) and diastolic BP (DBP) were 136 ± 18 and 82 ± 11 mmHg, respectively. Sodium intake was positively associated with SBP (ß = 0.042 mmHg/mmol/24 h, P = 0.002) and DBP (ß = 0.023 mmHg/mmol/24 h, P = 0.007), independent of potential confounders. Conclusions - Although RTR had a lower sodium intake than healthy controls, their intake still exceeded current guidelines. Reduction of sodium intake to recommended amounts could reduce SBP by 4–5 mmHg. Better control of sodium intake may help to prevent graft failure and mortality due to hypertension among RTR

The Biobank of Nephrological Diseases in the Netherlands cohort: the String of Pearls Initiative collaboration on chronic kidney disease in the university medical centers in the Netherlands

Despite advances in preventive therapy, prognosis in chronic kidney disease (CKD) is still grim. Clinical cohorts of CKD patients provide a strategic resource to identify factors that drive progression in the context of clinical care and to provide a basis for improvement of outcome. The combination with biobanking, moreover, provides a resource for fundamental and translational studies. In 2007, the Dutch government initiated and funded the String of Pearls Initiative (PSI), a strategic effort to establish infrastructure for disease-based biobanking in the University Medical Centres (UMCs) in the Netherlands, in a 4-year start-up period. CKD was among the conditions selected for biobanking, and this resulted in the establishment of the Biobank of Nephrological Diseases-NL (BIND-NL) cohort. Patients with CKD Stages 1-4 are eligible. The data architecture is designed to reflect routine care, with specific issues added for enrichment, e.g. questionnaires. Thus, the collected clinical and biochemical data are those required by prevailing guidelines for routine nephrology care, with a minimal dataset for all patients, and diagnosis-specific data for the diagnostic categories of primary and secondary glomerular disorders and adult dominant polycystic kidney disease, respectively. The dataset is supplemented by a biobank, containing serum, plasma, urine and DNA. The cohort will be longitudinally monitored, with yearly follow-up for clinical outcome. Future linking of the data to those from the national registries for renal replacement therapy is foreseen to follow the patients' lifeline throughout the different phases of renal disease and different treatment modalities. In the design of the data architecture, care was taken to ensure future exchangeability of data with other CKD cohorts by applying the data harmonization format of the Renal DataSHaPER, with a dataset based upon standardized indicator sets to facilitate collaboration with other CKD cohorts. Enrolment started in 2010, and over 2200 eligible patients have been enrolled in the different UMCs. Follow-up of enrolled patients has started, and enrolment will continue at a slower rate. The aggregation and standardization of clinical data and biosamples from large numbers of CKD patients will be a strategic resource not only for clinical and translational research, but also by its basis in routine clinical care for clinical governance and quality improvement projects