June 8, 2010 -- Short people have a higher risk of heart health problems than tall people, according to a new study.
''The shorter you are, the higher risk you have of developing cardiovascular disease," says Tuula Paajanen, MD, a researcher at the University of Tampere, Finland.
Short people, she found, also had an increased risk of heart attacks and earlier death than taller people. Overall, she says, the risk of getting heart disease and dying from it early is 1.5 times higher for short people than for tall people.
The report, in which Paajanen analyzes 52 previously published studies, is published in the European Heart Journal.
For nearly 60 years, researchers have debated a potential link between height and heart disease, with the first report finding short people at a health disadvantage published in 1951.
So Paajanen and her team did medical literature searches, selecting the most scientifically sound studies -- totaling 52 -- from the 1,907 articles she found on the topic. In all, more than 3 million people were included in the 52 studies they reviewed.
What's Short? What's Tall?
Short and tall are relative, of course, so for the review Paajanen compared the tallest groups with the shortest groups, defining each.
- Short men were defined as those less than about 5 feet 5 inches tall, while short women were those below about 5 feet.
- Tall men were those over about 5 feet 9 and 1/2 inches, and tall women over about 5 feet 5 and 1/2 inches.
After analyzing all 52 studies, Paajanen found an increased risk for health problems and earlier death for the shortest group compared to the tallest.
- Short stature increased the risk of heart disease illness and death by 1.5 times.
- Short men had a 37% increased risk for dying from any cause, and short women a 55% increased risk.
- Both short men and short women had a 52% increased risk of having a heart attack.
Exactly why the shortest people had more heart disease and earlier death than the tallest isn't known, but Paajanen can speculate. "My favorite hypothesis is that shorter people would have narrower arteries, because this hypothesis hasn't been studied very much. In recent studies using angiographic measurements, the coronary artery diameter was correlated with height and body weight, so there might be a point to it," she tells WebMD.
The smaller arteries, she speculates, may be occluded earlier in life, leading to heart disease, due to factors such as poorer socioeconomic background and poor nutrition, for instance.
Paajanen says that her results suggest that ''height may be considered a possible independent factor" when physicians are calculating a person's heart disease risk.
The new review doesn't lay the question to rest, says Thomas Samaras, a San Diego researcher who has published on the topic and written a book about human body size and its effects as well as a book called The Truth About Your Height. "There are many neutral studies [about the effect of height on heart health] and many that disagree."
''I believe what they found is true," he says. "But I don't believe the results are true. I think they are confused by what we call confounding factors," he tells WebMD. "We know women are shorter than men and they have less heart disease."
Samaras contends it's not the short stature that is linked with higher heart disease rates and other problems, but something that could be associated with the short stature.
For instance, he says, a low-birth-weight baby is likely to grow up short, he says. "If a baby is low birth weight we tend to overfeed," he says. It could be the excess weight, not the short stature, driving the heart disease risk, he says.
In a study Samara published last year in Experimental Gerontology, he says, "I found that men were 9% taller than women and had a 9% lower life expectancy."
Samaras also points to centenarians and observes that many are short and lean.
In an editorial accompanying the review, Jaakko Tuomilehto of the University of Helsinki also questions whether the differences in risk are due to the height factor or something else. But regardless, he writes, short people may be wise to ''take coronary risk factor control more seriously."
Not that tall people are off the hook, he says, warning that they ''are not protected against coronary heart disease, and they also need to pay attention to the same risk factors as shorter people."
''Height is only one factor that may contribute to heart disease risk," Paajanen says. ''Whereas people have no control over their height or genetics, they can control their weight, lifestyle habits such as smoking, drinking and exercise -- and all of these together affect their heart disease risk."