High blood pressure is a complex condition that can be caused by many factors, including obesity, diet, genetics, or stress. Maintaining a healthy balance of sodium in the body is important for adequate blood pressure control. Some individuals experience sustained high blood pressure during periods of extended stress, combined with the inability to excrete enough sodium through urine to re-establish normal blood pressure levels. This type of stress-induced high blood pressure is related to interleukin-6 (IL-6), a protein that stimulates inflammation and immune responses. To determine the interaction between stress, inflammation, and genetics, this study will examine the role of IL-6 in regulating sodium levels and blood pressure in individuals undergoing stress. This information will be useful in determining new ways to evaluate risk factors for high blood pressure.~This study will examine previously collected DNA samples from young adults who participated in prior genetic studies. There will be no study visits for participants. IL-6, IL-6R, glycoprotein 130 (gp130), and C-reactive protein (CRP) genes will be analyzed in all samples; changes in plasma levels of IL-6 and CRP in response to stress will be examined in selected samples. The parents of participants will be asked to provide cheek swabs for additional DNA analysis.
High blood pressure affects nearly one third of all individuals in the United States. If left untreated, it can lead to stroke, heart failure, heart attack, kidney failure, or blindness. For many people, the exact cause of high blood pressure is unknown, but it is believed that both genetic and environmental factors contribute to the development of the condition. The purpose of this study is to examine the importance of genetics, inflammation, and stress on the development of high blood pressure.