Orthostatic Hypotension Ups Risk of HF by 50%

March 22, 2012

March 21, 2012 (Chapel Hill, North Carolina) — People with orthostatic hypotension (OH) have around a 50% higher risk of developing heart failure than those without, according to a new analysis of the Atherosclerosis Risk in Communities (ARIC) study [1]. Dr Christine D Jones (University of North Carolina, Chapel Hill) and colleagues report their findings online March 19, 2012 in Hypertension.

The study is not the first to associate orthostatic hypotension with heart failure — two European cohort studies also found a similar link — but it is the first to pinpoint this "in both white and African American participants," says Jones. And "our study also adds an evaluation of medications known to cause orthostatic hypotension," she notes.

"The main messages are that OH appears to be associated with the development of HF, although the association may be partially explained by hypertension," she says. "The association did not vary greatly between white and African American participants, and medications for hypertension do not appear to play a large role. Finally, the association was stronger in younger than in older patients in our study." 

Although it's not yet clear whether adding orthostatic hypotension to HF risk-prediction models might improve the accuracy of such models, orthostatic BP measurements require no additional equipment and are easy to teach patients, Jones says. However, she acknowledges that orthostatic measurements take more time to perform than a regular BP measurement, "because BP has to be measured while a person is lying down and then again right after they stand up." 

OH: A marker of subclinical atherosclerosis contributing to HF risk

Jones and colleagues followed 12 363 adults in ARIC, free of prevalent heart failure and with baseline orthostatic measurements. Orthostatic hypotension was defined as a decrease of systolic BP of ≥20 mm Hg or diastolic BP of ≥10 mm Hg with position change from supine to standing. Incident HF was identified from hospitalization or death-certificate disease codes.

We speculate that OH preceding HF may be a marker of subclinical atherosclerosis that is facilitated by hypertension and potentially by other risk factors to contribute to HF development.

Over 17.5 years of follow-up, "we found a significant association between OH and incident HF that was robust to adjustment for multiple HF risk factors," say Jones et al (hazard ratio 1.54).

The association was similar across race and sex groups. A stronger association was identified in those under 55 years of age (HR 1.90) than in individuals aged 55 and over (HR 1.37; interaction p=0.034).

While the link between OH and HF persisted with exclusion of those with diabetes, coronary heart disease, and those on antihypertensive, psychiatric, or Parkinson's-disease medications (which are known to cause OH), the exclusion of those with hypertension modestly attenuated the association (HR 1.34), they note. (Hypertension was defined as those with elevated BP or use of antihypertensive medication at baseline.)

"Given our findings, we speculate that OH preceding HF may be a marker of subclinical atherosclerosis that is facilitated by hypertension and potentially by other risk factors to contribute to HF development," the researchers conclude.

The authors report no conflicts of interest.

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