A new model to predict the life expectancy of older people relies less on their specific disease diagnoses and more on factors such as their ability to grocery shop, the amount of certain small cholesterol particles in their blood, and whether they have never or only occasionally smoked.

According to Duke Health,  these findings from a study led by Duke Health researchers offer a way to predict how long a person will live over the age of 70. The researchers identified markers that could tell if a person will live two, five or 10 more years.

“This study was designed to determine the proximal causes of longevity — the factors that portend whether someone is likely to live two more years or 10 more years,” said Dr. Virginia Byers Kraus, a professor in Medicine, Pathology and Orthopedic Surgery at Duke University School of Medicine and lead author of the study. “Properly applied, these measures could help determine the benefits and burdens of screening tests and treatment for older people.”

The scientist came across a gift of blood samples drawn in 1992 from people who were at least 71 years of age. The samples had been stored at the National Institutes of Health and were scheduled for destruction when the Duke scientists stepped in and analyzed them.

The blood samples were taken before statin drugs were in widespread use and could skew the results of their study.  The study participants had already been followed for several years and had filled out questionnaires about their health habits and histories.

Using current, sophisticated analytical tools, the researchers were able to identify a core set of 17 predictive variables that influence longevity. They found that a leading factor that extended lifespan was physical function, defined as the ability to go shopping or clean their houses. Surprisingly, having cancer or heart disease was not among the main predictors of lifespan.

For older people living two years beyond the time their blood was drawn, the leading factor associated with aging was having an abundance of “good” high-density lipoprotein (HDL) cholesterol made of very small particles.

“This was especially surprising,” said Kraus. “We hypothesize that these very small HDL particles are the size that is best for scavenging and clearing endotoxin, a potent inflammation-causing molecule from gut microbes, from the circulation. The small particles may also be the best to get into the nooks and crannies of cells to remove bad cholesterol, so having more of them could provide this protective benefit.”

Among the longest survivors, those living more than 10 years after their blood was drawn, the best predictor of longevity was a person’s smoking history, with nonsmokers faring best.

Dr. Gabe Mirkin, author of The Healthy Heart Miracle and a leading longevity expert, adds that the study found that people over the age of 70 were more likely to live at least 10 years longer if they had other lifestyle factors such as:

• Ability to groom themselves. Lack of motor control required for personal grooming was a strong predictor of a short life.

• Having a high score on a cognitive function test such as the Short Portable Mental Status Questionnaire (SPMSQ).

• Exercising regularly. The greater the frequency and intensity of exercise the more likely a person was to live longer.

Mirkin points out that the standard tests used by doctors today to measure lipid levels in the blood are not as dependable in predicting lifespan as the test for small-size HDL particles.

“This study found that high levels of small particle HDL are a strong predictor of longevity,” he says, according to Dr. Mirkin.com. “However, the amount of small particle HDL in your bloodstream appears to be genetic, and as far as we know today, it cannot be improved with lifestyle changes or drugs. The lifestyle changes associated with increased longevity include anything that uses your muscles or your mind. The more debilitated you are, the shorter your expected lifespan and the more active you are, the longer your expected lifespan.”