RESUMO
BACKGROUND: Environmental surveys have characterized trace elements such as lead (Pb), cadmium (Cd) and arsenic (As) as potential risk factors for non-communicable diseases. There have been few studies conducted in the Caribbean region to explore, define or clarify such findings locally. Furthermore, local pollution control efforts are often juxtaposed against more seemingly immediate economic concerns in poor communities. OBJECTIVES: The present commentary is a call to action for the evaluation of potentially hazardous elements as potential risk indicators and/or factors of common noncommunicable diseases in the Caribbean. DISCUSSION: Findings from Jamaican studies have identified exposure to potentially hazardous elements (PHE) via water, food, and other anthropogenic activities to the detriment of the resident population. Several attempts have been made to abate toxic metal exposure in children with relative success. However, high levels of PHE have been noted in vulnerable populations such as patients with hypertension, diabetes mellitus and chronic kidney disease. Currently, there is low priority towards infrastructure building within the Caribbean region that would promote and sustain long term monitoring and better inform environmental polices impacting chronic diseases. CONCLUSIONS: Further investigations are needed to clarify the role that PHE play in increasing the risk or progression of non-communicable diseases, especially in vulnerable groups. COMPETING INTERESTS: The authors declare no competing financial interests.
RESUMO
BACKGROUND: The kidney is central to many complex pathways in the body and kidney injury can precipitate multiple negative clinical outcomes. The resultant effect on nutrition and elemental body burden is bi-directional, confounding the very complex pathways that maintain homeostasis. These elemental changes themselves increase the risk of nutritional and biochemical disturbances. OBJECTIVES: The aim of the present study was to describe how toxic elements interface with complications of chronic kidney disease (CKD). METHODS: The present review included studies focusing on the molecular mechanisms induced by exposure to elements with known nephrotoxic effects and associated health complications in CKD patients. DISCUSSION: Many non-essential elements have nephrotoxic activity. Chronic injury can involve direct tubular damage, activation of mediators of oxidative stress, genetic modifications that predispose poor cardiovascular outcomes, as well as competitive uptake and element mobilization with essential elements, found to be deficient in CKD. Cardiovascular disease is the most common cause of mortality among CKD patients. Oxidative stress, a common denominator of both deficient and excess element body constitution, underlies many pathological derivatives of chronic kidney disease. Bone disorders, hematological dysfunction and dysregulation of acid-base balance are also prevalent in kidney patients. The largest contribution of toxic element body burden results from environmental exposure and lifestyle practices. However, standard medical therapies may also potentiate toxic element accumulation and re-injury of vulnerable tissue. CONCLUSIONS: For CKD patients, the cumulative effect of toxic elements persists throughout the disease and potentiates complications of CKD. Medical management should be coordinated between a medical team, dietitians and clinical researchers to mitigate those harmful effects. COMPETING INTERESTS: The authors declare no competing financial interests.
RESUMO
BACKGROUND: The role of nonselective beta-blockers in cirrhotic patients with ascites has been recently questioned; however, definitive evidence in this regard is still lacking. AIMS: To analyze published data on the influence of nonselective beta-blockers as compared to control group on survival of cirrhotic patients with ascites. METHODS: Computerized bibliographic search on the main databases was performed. Hazard ratios from Kaplan-Meier curves were extracted in order to perform an unbiased comparison of survival estimates. Secondary outcomes were mortality in patients with refractory ascites, pooled rate of nonselective beta-blockers interruption, spontaneous bacterial peritonitis and hepato-renal syndrome incidence. RESULTS: Three randomized controlled trials and 13 observational studies with 8279 patients were included. Overall survival was comparable between the two groups (hazard ratio = 0.86, 0.71-1.03, p = 0.11). Study design resulted as the main source of heterogeneity in sensitivity analysis and meta-regression. Mortality in refractory ascites patients was similar in the two groups (odds ratio = 0.90, 0.45-1.79; p = 0.76). No difference in spontaneous bacterial peritonitis (odds ratio = 0.78, 0.47-1.29, p = 0.33) and hepato-renal syndrome incidence (odds ratio = 1.22, 0.48-3.09; p = 0.67) was observed. Pooled rate of nonselective beta-blockers interruption was 18.6% (5.2-32.1%). CONCLUSIONS: Based on our findings, nonselective beta-blockers should not be routinely withheld in patients with cirrhosis and ascites, even if refractory.
