Influence of renin angiotensin system gene polymorphisms on visit-to-visit blood pressure variability in hypertensive patients

The renin angiotensin aldosterone system and insulin resistance in humans

Alterations in the renin angiotensin aldosterone system (RAAS) contribute to the underlying pathophysiology of insulin resistance in humans; however, individual differences in the treatment response of insulin resistance to RAAS blockade persist. Thus, understanding inter-individual differences in the relationship between the RAAS and insulin resistance may provide insights into improved personalized treatments and improved outcomes. The effects of the systemic RAAS on blood pressure regulation and glucose metabolism have been studied extensively; however, recent discoveries on the influence of local tissue RAAS in the skeletal muscle, heart, vasculature, adipocytes, and pancreas have led to an improved understanding of how activated tissue RAAS influences the development of insulin resistance and diabetes in humans. Angiotensin II (ANGII) is the predominant RAAS component contributing to insulin resistance; however, other players such as aldosterone, renin, and ACE2 are also involved. This review examines the role of local ANGII activity on insulin resistance development in skeletal muscle, adipocytes, and pancreas, followed by a discussion of the other RAAS components implicated in insulin resistance, including ACE2, Ang1-7, renin, and aldosterone.

Association of BP variability with mortality among African Americans with CKD

BACKGROUND AND OBJECTIVES

Increased systolic BP visit-to-visit variability (SBV) may be associated with higher overall mortality and cardiovascular events. However, few studies have examined these associations in patients with CKD, and the relation of SBV with CKD progression and ESRD has not been shown. This study analyzed the association of SBV with overall mortality, cardiovascular mortality, cardiovascular events, and renal events among individuals enrolled in the African American Study of Kidney Disease (AASK) trial.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

This was a prospective observational study of 908 participants during the trial phase of the AASK study, with at least 1 year of BP measurements available and followed for 3-6.4 years. SBV was calculated as the SD of the systolic pressure from five visits occurring 3-12 months after randomization. The association of SBV with risk of overall mortality, cardiovascular mortality, a composite of fatal and nonfatal cardiovascular events, and a composite of renal events was assessed using proportional hazards regression and adjusting for multiple potential confounders.

RESULTS

Greater SBV was associated with higher overall mortality. The adjusted hazard ratio (95% confidence interval) was 2.82 (1.14-6.95) comparing the highest with lowest tertile of SBV. A similar comparison revealed that greater SBV was also associated with cardiovascular mortality (adjusted hazard ratio, 4.91; 1.12-21.50). SBV was associated with both the cardiovascular renal composite endpoints in unadjusted but not adjusted analyses.

CONCLUSIONS

In African Americans with CKD, SBV is strongly and independently associated with overall and cardiovascular mortality.