Reflection Magnitude and Death (page 958)
Although the systolic and diastolic blood pressures contain important prognostic information, further knowledge can still be gained from analysis of the arterial waveform. Wave reflections, returning to the heart from the periphery in late systole, affect the central pressure waveform and increase the load on the left ventricle. In this study, we performed wave separation analysis on 5984 healthy individuals from the Multi-Ethnic Study of Atherosclerosis cohort and determined the magnitude of the forward (Pf) and backward-traveling (Pb) waves using a physiological flow approach. We found that their ratio (reflection magnitude, Pb/Pf) related to mortality, even after adjustment for traditional atherosclerotic risk factors and blood pressure. Importantly, the forward and backward waves were associated with mortality in opposite directions, with increased backward wave but decreased forward wave amplitude, associating with increased mortality. These relationships were strongest for cardiovascular death. In summary, the arterial waveform provides important incremental information beyond its peak and trough. Both the magnitudes of the forward and backward waves demonstrate significant prognostic relationships to mortality.
CD8+ T cells and Hypertension (page 1108)
Recent studies have implicated a role of T cells in the genesis of hypertension; however, mechanisms underlying T cell activation in this disease remain poorly defined. Naïve T cells develop in the thymus and migrate to secondary lymphoid organs, including the spleen and lymph nodes. The Vβ region of the T cell receptor gene exhibits enormous diversity, providing recognition of virtually any foreign peptide. Antigen presentation leads to expansion of T cell clones that are specific for individual antigens. In this study, we found that hypertension is associated with expansion of 3 Vβ subtypes in CD8+ T cells of the kidney. We further found that mice lacking CD8+ T cells develop blunted hypertension, as did mice with only 1 T cell receptor specific for an albumin peptide (OT1xRAG-1−/− mice, see Figure). In normal mice and mice lacking CD4+ T cells, we found that hypertension is associated with attenuation of the renal microvasculature and that CD8−/− mice are protected against this vascular perturbation. In another recent study, we identified isoketal-modified proteins as potential neoantigens in hypertension. Isoketals are oxidized products of arachidonic acid that rapidly ligate to proteins. Taken together with our present article in Hypertension, our data indicate that renal oxidative injury leads to formation of oxidatively modified proteins that are recognized as nonself and lead to an oligoclonal population of CD8+ T cells. Efforts to scavenge isoketals or reduce their formation will likely be effective in reducing inflammation, reducing renal injury, and lowering blood pressure.
Blood Pressure Control in Uninsured Adults (page 997)
Hypertension control in the United States is generally better in white than in black and Hispanic adults. However, all 3 race/ethnicity groups experienced significant and similar absolute percentage improvements in hypertension control between 1988 and 2008. Several reports documented lower hypertension control in uninsured and insured adults at various time points. We were concerned that uninsured individuals might be falling further behind insured adults in hypertension control. Although anticipating the gap in hypertension control between the insured and uninsured might increase, the absence of progress in the uninsured from 1988 to 2010 was unexpected (Figure). Yet during this time period, the age gap in hypertension control, with better control in younger than in older adults, was essentially eliminated.
The uninsured have lower incomes and less education than the insured, which may contribute to disparate hypertension control. Hypertension control was similar among privately and publicly insured adults from 1988 to 2010 (Figure), although education and income were similar in publicly insured and uninsured adults. Thus, insurance emerges as a major factor in hypertension control. The uninsured had fewer healthcare visits, were less aware of hypertension, and less likely to be treated when aware and controlled when treated. Despite the Affordable Care Act, 31 million Americans are likely to remain uninsured. It is important to overcome access barriers to evidence-based care and medications to translate proven benefits of hypertension control to currently uninsured adults.
- © 2014 American Heart Association, Inc.