By RONI CARYN RABIN Published: April 13, 2009 Former prison inmates are more likely than those who have never been incarcerated to have high blood pressure as young adults and to develop a dangerous thickening of the heart’s left ventricle, a new study has found. Experts have long known that inmates are at greater risk for infectious diseases such as H.I.V., hepatitis and tuberculosis, but less is known about whether they are more likely to develop such chronic conditions as hypertension. The new study suggests that they might be, and that traditionally suspect risk factors for heart disease — such as drug and alcohol use, obesity and poverty — do not entirely explain the increased risk. Although the association was strongest for black men and the less educated, who also have the highest incarceration rates, lead author Dr. Emily A. Wang of the Yale University School of Medicine said those factors did not explain the increased risk. “It’s not that they’re black. It’s not that they’re poor. It’s not that they smoke or use cocaine or methamphetamine or drink a lot. We adjusted for all of that. . . .There’s something specific about having been incarcerated,” said Dr. Wang, formerly of San Francisco General Hospital and the University of California, San Francisco. Some experts have suggested that increased hostility or stress hormones related to the prison experience may increase the risk of hypertension and atherosclerosis. The study was published on Monday in the Archives of Internal Medicine. Dr. Wang and her colleagues at U.C.S.F. and the University of Alabama at Birmingham analyzed data from the Coronary Artery Risk Development In Young Adults study, which started following more than 5,000 young people from four cities in the United States when they were between the ages of 18 and 30 in order to determine their risks for heart disease. Some 4,350 who were followed for at least five years were included in the analysis; 288, or 7 percent, reported having been incarcerated before the study started. After five years, when the participants were between 23 and 35 years old, 12 percent of the former inmates who did not have high blood pressure at the start of the study had developed hypertension, compared with 7 percent of those who had never been in jail, the researchers found. Even after the scientists adjusted for risk factors like smoking, alcohol, drug use and income, they found that former inmates were 60 percent more likely than those who had never been jailed to have developed hypertension. Though the increase was not statistically significant, they also appeared to be at greater risk for developing left ventricular hypertrophy, a thickening of the wall of the heart’s left ventricle, which often results from high blood pressure and increases the risk of heart attack, heart failure and sudden cardiac arrest. Only 0.6 percent of participants without a history of incarceration developed left ventricular hypertrophy, compared with 2 percent of those who had been in prison. “This data supports the possibility that incarceration actually has a role in the development of certain chronic diseases,” said Dr. Ingrid Binswanger, assistant professor at the University of Colorado Denver School of Medicine and author of an earlier study that found high death rates among recently released prisoners. “It’s a novel study in that they even assessed incarceration history.”