Differences in the Food Consumption Between Kidney Stone Formers and Nonformers in the Swiss Kidney Stone Cohort.

OBJECTIVE: Diet has a major influence on the formation and management of kidney stones. However, kidney stone formers' diet is difficult to capture in a large population. Our objective was to describe the dietary intake of kidney stone formers in Switzerland and to compare it to nonstone formers. METHODS: We used data from the Swiss Kidney Stone Cohort (n = 261), a multicentric cohort of recurrent or incident kidney stone formers with additional risk factors, and a control group of computed tomography-scan proven nonstone formers (n = 197). Dieticians conducted two consecutive 24-h dietary recalls, using structured interviews and validated software (GloboDiet). We took the mean consumption per participant of the two 24-h dietary recalls to describe the dietary intake and used two-part models to compare the two groups. RESULTS: The dietary intake was overall similar between stone and nonstone formers. However, we identified that kidney stone formers had a higher probability of consuming cakes and biscuits (odds ratio (OR) [95% CI] = 1.56[1.03; 2.37]) and soft drinks (OR = 1.66[1.08; 2.55]). Kidney stone formers had a lower probability of consuming nuts and seeds (OR = 0.53[0.35; 0.82]), fresh cheese (OR = 0.54[0.30; 0.96]), teas (OR = 0.50[0.3; 0.84]), and alcoholic beverages (OR = 0.35[0.23; 0.54]), especially wine (OR = 0.42[0.27; 0.65]). Furthermore, among consumers, stone formers reported smaller quantities of vegetables (ß coeff[95% CI] = - 0.23[- 0.41; - 0.06]), coffee (ß coeff = - 0.21[- 0.37; - 0.05]), teas (ß coeff = - 0.52[- 0.92; - 0.11]) and alcoholic beverages (ß coeff = - 0.34[- 0.63; - 0.06]). CONCLUSION: Stone formers reported lower intakes of vegetables, tea, coffee, and alcoholic beverages, more specifically wine, but reported drinking more frequently soft drinks than nonstone formers. For the other food groups, stone formers and nonformers reported similar dietary intakes. Further research is needed to better understand the links between diet and kidney stone formation and develop dietary recommendations adapted to the local settings and cultural habits.

Impact of potassium citrate on urinary risk profile, glucose and lipid metabolism of kidney stone formers in Switzerland.

BACKGROUND: Hypocitraturia and hypercalciuria are the most prevalent risk factors in kidney stone formers (KSFs). Citrate supplementation has been introduced for metaphylaxis in KSFs. However, beyond its effects on urinary parameters and stone recurrence, only a few studies have investigated the impact of citrate on other metabolic pathways such as glucose or lipid metabolism. METHODS: We performed an observational study using data from the Swiss Kidney Stone Cohort. Patients were subdivided into two groups based on treatment with potassium citrate or not. The outcomes were changes of urinary risk parameters, haemoglobin A1c (HbA1c), fasting glucose, cholesterol and body mass index (BMI). RESULTS: Hypocitraturia was present in 19.3% of 428 KSFs and potassium citrate was administered to 43 patients (10.0%) at a mean dosage of 3819 ± 1796 mg/day (corresponding to 12.5 ± 5.9 mmol/ day). Treatment with potassium citrate was associated with a significantly higher mean change in urinary citrate (P = 0.010) and urinary magnesium (P = 0.020) compared with no potassium citrate treatment. Exogenous citrate administration had no effect on cholesterol, fasting glucose, HbA1c and BMI. Multiple linear regression analysis demonstrated no significant association of 1,25-dihydroxyvitamin D3 [1,25(OH)2 D3] levels with urinary citrate excretion. CONCLUSION: Potassium citrate supplementation in KSFs in Switzerland resulted in a beneficial change of the urinary risk profile by particularly increasing anti-lithogenic factors. Fasting glucose, HbA1c, cholesterol levels and BMI were unaffected by potassium citrate therapy after 3 months, suggesting that potassium citrate is safe and not associated with unfavourable metabolic side effects. Lastly, 1,25(OH)2 D3 levels were not associated with urinary citrate excretion.

[The Multimorbid Patient: Use of New Oral Anticoagulants in Patients with Chronic Kidney Disease]. / Der multimorbide Patient: Einsatz neuer oraler Antikoagulanzien bei Patienten mit chronischer Niereninsuffizienz.

The Multimorbid Patient: Use of New Oral Anticoagulants in Patients with Chronic Kidney Disease Abstract. Increasing life expectancy in Western countries is associated with a high prevalence of multiple chronic diseases which is defined by the term "multimorbidity". Many of these patients suffer from chronic kidney disease (CKD) and thrombogenic comorbidities such as atrial fibrillation with the need for oral anticoagulation. For decades vitamin K antagonists have been exclusively prescribed for oral anticoagulation. However, due to altered pharmacokinetics and bioavailability of these drugs in CKD, a significant risk of bleeding exists. The introduction of direct oral anticoagulants as a new and promising alternative to vitamin K antagonists was -especially for CKD patients - highly anticipated. However, data from randomized studies are missing for older patients with advanced CKD. Consequently, a careful evaluation of the risk-benefit ratio is recommended for this sensitive patient population.

The life-extending gene Indy encodes an exchanger for Krebs-cycle intermediates.

A longevity gene called Indy (for 'I'm not dead yet'), with similarity to mammalian genes encoding sodium-dicarboxylate cotransporters, was identified in Drosophila melanogaster. Functional studies in Xenopus oocytes showed that INDY mediates the flux of dicarboxylates and citrate across the plasma membrane, but the specific transport mechanism mediated by INDY was not identified. To test whether INDY functions as an anion exchanger, we examined whether substrate efflux is stimulated by transportable substrates added to the external medium. Efflux of [14C]citrate from INDY-expressing oocytes was greatly accelerated by the addition of succinate to the external medium, indicating citrate-succinate exchange. The succinate-stimulated [14C]citrate efflux was sensitive to inhibition by DIDS (4,4'-di-isothiocyano-2,2'-disulphonic stilbene), as demonstrated previously for INDY-mediated succinate uptake. INDY-mediated efflux of [14C]citrate was also stimulated by external citrate and oxaloacetate, indicating citrate-citrate and citrate-oxaloacetate exchange. Similarly, efflux of [14C]succinate from INDY-expressing oocytes was stimulated by external citrate, alpha-oxoglutarate and fumarate, indicating succinate-citrate, succinate-alpha-oxoglutarate and succinate-fumarate exchange respectively. Conversely, when INDY-expressing Xenopus oocytes were loaded with succinate and citrate, [14C]succinate uptake was markedly stimulated, confirming succinate-succinate and succinate-citrate exchange. Exchange of internal anion for external citrate was markedly pH(o)-dependent, consistent with the concept that citrate is co-transported with a proton. Anion exchange was sodium-independent. We conclude that INDY functions as an exchanger of dicarboxylate and tricarboxylate Krebs-cycle intermediates. The effect of decreasing INDY activity, as in the long-lived Indy mutants, may be to alter energy metabolism in a manner that favours lifespan extension.