AT THE AHA SCIENTIFIC SESSIONS
NEW ORLEANS (FRONTLINE MEDICAL NEWS) – Young adults whose parents develop hypertension before age 55 years are themselves at sharply increased risk of developing the disease, according to a new report from the Framingham (Mass.) Heart Study.
“Our results demonstrate that early-onset but not late-onset hypertension in parents is a strong risk factor for incident hypertension. It may be important for physicians to distinguish between early- and late-onset hypertension as a familial trait when assessing an individual’s risk for hypertension,” Teemu J. Niiranen, MD, said at the American Heart Association scientific sessions.
Compared with the offspring of Framingham participants who were normotensive, those with one parent who developed hypertension before age 55 years were at twofold increased risk of subsequent hypertension. If both parents had hypertension before age 55 years, the risk in their offspring was 3.5-fold greater than when both parents were normotensive, according to Dr. Niiranen of Boston University.
He reported on 1,635 participants in the Offspring cohort of the Framingham Heart Study who were normotensive when they enrolled in the prospective study beginning in 1972. At that time, they averaged 32 years of age. They were followed for a mean of 26 years. Like their parents who enrolled in the Original cohort of the landmark study beginning in 1948, they underwent meticulous blood pressure measurement roughly every 2 years.
Dr. Niiranen and his coinvestigators divided the Offspring cohort into four groups based upon parental hypertension status. There were 107 offspring with normotensive parents, 480 with one or both parents having developed late-onset hypertension after age 55 years, 721 offspring who had one parent with onset of hypertension before age 55 years, and 327 with both parents having early-onset hypertension.
The incidence rate of hypertension in the Offspring cohort climbed in concert with parental early hypertension status. So did the multivariate-adjusted relative risk of the disease, compared with children of normotensive parents.
Moreover, the earlier in life the parents developed hypertension, the earlier their offspring did, too.
Session moderator David J. Maron, MD , of Stanford (Calif.) University, commented, “Everybody’s thinking ‘genetics’ as we look at your findings. But do you have any way to tease out nature versus nurture in understanding the association?”
Dr. Niiranen replied that in a separate study of three generations of Framingham participants, the investigators incorporated two lifestyle factors in their analysis: level of exercise and sodium intake.
“Those didn’t have much effect on the results, so it seems like genetics is driving most of the outcome,” he said.
Dr. Niiranen reported having no financial conflicts of interest regarding his study, sponsored by the National Heart, Lung, and Blood Institute.