Height influences heart attack risk

A person's height can influence their longterm health and risk for certain medical conditions in a number of ways. Now a study published Thursday in the New England Journal of Medicine adds to the growing evidence that shorter people face an increased risk for coronary heart disease.

"We've know about a link since the 1950s about height and health," cardiologist and CBS News medical contributor Dr. Tara Narula told "CBS This Morning." "But what we didn't know is if your height is influencing your heart health or are there external factors like your nutrition as a child or socioeconomic status."

For the study, researchers conducted genetic testing to sequence the genomes of nearly 200,000 people with and without heart disease. In their analysis, they identified genetic code that influenced height and looked at the link to coronary heart disease.

The researchers found that for each two and a half inches shorter, a person had a 13.5 percent increased risk for coronary heart disease.

For example, a person who is 5 feet tall has an approximately 13.5 percent higher risk of heart disease than someone who's 5 feet 2.5 inches tall.

Similarly, compared with a 6-foot-tall person, someone who is 5 feet tall could have a 60 percent higher risk for coronary heart disease.

To further analyze why this may be the case, the researchers measured the influence of 12 risk factors such as blood pressure, weight and diabetes. They determined that only LDL (bad) cholesterol and triglycerides could account for part of the association between height and risk for heart disease. But this didn't provide a full explanation.

"There's a lot of other hypotheses of what might be going on," said Narula. "For instance, if you are shorter you have smaller caliber diameter coronary arteries that might be easier for those arteries to get blocked over time. What researchers propose is that there are shared biological pathways that produce bone and muscle growth through hormones and proteins might also be causing increased cell growth in the artery walls and inflammation. And then the third possible theory is that maybe tall people somehow live healthier lifestyles. They exercise more, they smoke less and that's really what we're seeing."

The study only confirmed the link between height and coronary heart disease risk in men, most likely because there were more men enrolled in this particular study. Prior research has indicated that there is a link between height and heart attack risk for women as well.

However, Narula points out that being short does have its health advantages. Research in the past has shown that tall people may be at a higher risk for cancer, possibly because they have more cells in the body, and therefore a higher cell turnover. And statistically, short people have a longer lifespan overall.

"The bottom line is we're not going to tell someone when they come into our office, 'You're 5-foot-2, take a statin,' 'You're 5-foot-6, don't.' The same risk factors right now are the same ones for tall and short people," she said.