Kyoto Nexus meeting心得報告
The Kyoto Nexus meeting is a meeting organized by International Society of Nephrology (ISN). The meeting is for translating the basic research information into the clinical practice. This is the first time that “Nexus” meeting is held in Asia. The number of participants exceeds more than 900 nephrologists. The topics focus on the cardiovascular disease in chronic kidney disease. This is also a field we are going to approach. In addition to gain the novel information, there is another goal for this trip. We, Taiwan Society of Nephrology, intend to be the next host of Nexus meeting in Asia in 2011. We will like to to understand all the process in organizing a international meeting like this.
Increasing prevalence and incidence of end-stage renal disease (ESRD) is a global problem. Taiwan is a country with the highest prevalence and incidence of ESRD in the world. Furthermore, the prevalence of pre-dialysis chronic kidney disease (CKD) is also as high as 11.9% in Taiwan. The fact suggests a coming challenge in preventing and managing CKD in Taiwan. With this background, CKD has given a great impact on individual, family, society, and national health insurance in Taiwan.
Cardiovascular (CVD) is the leading cause of mortality and morbidity in CKD patients. CVD is associated with CKD progression and mortality. Preventing and treating CVD is a major issue in CKD care to slow down progression and reduce mortality. CVD in CKD is much more complex than patients without CKD. In addition to classic risk factors of CVD, CKD patients have CKD-specific CVD risk factors, such as inflammation, malnutrition, anemia, uremic toxin, calcium/phosphate imbalance, oxidative stress, and activation of renin-angiotensin system (RAS). This background information suggested a different clinical and pathophysiological difference of CVD in CKD.
We, Keelung Chang Gung Memorial Hospital, present 2 posters regarding to LVH and reversed epidemiology of cardiovascular disease in CKD patients. These data is the initial presentation of CKD cohort database in CGMH KL. There are many further ongoing studies to link the unique clinical phenomenon and basic research. The coming one is regarding the RAAS in chronic ischemic nephropathy.
With the help of Dean Cherng, we started to analyze the renal RAAS system expression in an animal model of chronic renal ischemia. We found that the RAAS is activated at the level of receptor. The renin change is secondary to blood pressure change. The RAAS blockade therapy has angiotensin II-independent effect on renal tissue remodeling. The finding is novel and deserves further investigation.
Another important issue is the re-emerge of Vitamin D in the cardiovascular protection. There is accumulating evidence for beneficial biological effect via binding of activated vitamin D with the vitamin D receptor (VDR) that go beyond calcium and bone homeostasis and regulation of parathyroid hormone (PTH) secretion. Treatment with vitamin d receptor agonists (VDRAs) is associated with reduced mortality in ESRD and CKD patients. Interestingly, these relations are independent of PTH levels and calcium x phosphorus product. This suggests the presence of biological functions of vitamin D that are independent of its interaction with the parathyroid glands. Because CKD leads to increased cardiovascular mortality, mechanisms in which VDRAs can influence cardiovascular disease are focus of many studies. These mechanisms comprise the potential ameliorating effects of VDRAs on atherosclerosis, arterial media calcification, cardiac hypertrophy, the renin-angiotensin system and thrombosis. Moreover, treatment strategies with VDRAs are discussed together with several recent observational studies. Treatment advice consists of correction of 25(OH) Vitamin D deficiency, low-dose calcitriol in patients with secondary hyperparathyroidism, and activated vitamin D analogues may be indicated when higher doses are needed to suppress PTH secretion. New insights into biological and clinical effects of VDRAs may broaden the patient group that may benefit from VDRA treatment to patients with CKD stage 3 to 5. All these information suggests a potential beneficial effect of VDRA in CKD patients.
With this background, we have all the VDRAs in hand and all the possibility to offer the CKD patients an integrated therapy for cardioprectecion. However, we can’t assess the Vitamin D level, which is crucial for assessing the Vitamin D deficiency in CKD patients. For this reason, we suggest our department of clinical pathology to establish an assay for Vitamin D. We have a large pool of patients, 1500 CKD and 600 ESRD patients, for the assay.