Long-term antiproteinuric effect of dual renin-angiotensin system blockade

Renin-angiotensin system blocking drugs

The two major classes of drugs that target the RAS are the angiotensin-converting enzyme (ACE) inhibitors and the selective AT1 receptor blockers (ARBs). Although both of these drug classes target angiotensin II, the differences in their mechanisms of action have implications for their effects on other pathways and receptors that may have therapeutic implications. Both ACEIs and ARBs are effective antihypertensive agents that have been shown to reduce the risk of cardiovascular and renal events. Direct inhibition of renin -the most proximal aspect of the RAS -became clinically feasible from 2007 with the introduction of aliskiren. This latter drug has been shown to be efficacious for the management of hypertension. Combined therapy of direct renin-inhibitors with ACEIs or ARBs has been tested in some clinical situations as congestive HF and proteinuria with diverse results. This article tries to offer an updated review of current knowledge on the use of RAS blocking drugs in clinical settings.

Bisphosphonate treatment and risk of esophageal cancer: a meta-analysis of observational studies

The use of bisphosphonates and the risk of esophageal cancer have recently received increasing concern and related studies have yielded controversial results. The present meta-analysis of observational studies shows that no clear association between bisphosphonate treatment and risk of esophageal cancer was observed.

INTRODUCTION

Epidemiological evidence suggests that bisphosphonate treatment can increase the risk of esophageal cancer. However, data on this issue are unstable and controversial. We conducted a meta-analysis to provide a quantitative assessment of the association between use of bisphosphonates and risk of esophageal cancer.

METHODS

We searched the Medline and Embase databases up to May 2012 to identify studies related to bisphosphonates and esophageal cancer. Summary effect estimates with 95 % confidence intervals (CI) were derived using a fixed or random effects model, depending on the heterogeneity of the included studies.

RESULTS

Seven epidemiologic studies that consisted of four cohort studies and three case-control studies were included in this meta-analysis. In our primary analysis, bisphosphonate treatment was not associated with risk of esophageal cancer in both cohort studies [pooled relative risk (RR) 1.23, 95 % CI 0.79-1.92] and case-control studies [pooled odds ratio (OR) 1.24, 95 % CI 0.98-1.57]. Evidence for the presence of significant heterogeneity was found in cohort studies (p = 0.009, I (2) = 74 %) but not in case-control studies (p = 0.338, I (2) = 7.8 %). In our secondary analysis, no significant increased risk of esophageal cancer was found in alendronate users (pooled RR 1.08, 95 % CI 0.67-1.75 in cohort studies; pooled OR 1.16, 95 % CI 0.82-1.63 in case-control studies).

CONCLUSIONS

Based on current evidences, bisphosphonate treatment was not significantly associated with excess risk of esophageal cancer.