Older adults with poor sense of smell—healthier people in particular—may see an almost 50 percent increase in their risk of dying within 10 years, research suggests.
“Poor sense of smell becomes more common as people age, and there’s a link to a higher risk for death,” says Honglei Chen, an epidemiologist at Michigan State University. “Our study is the first to look at the potential reasons why it predicts a higher mortality.”
Using data from the National Institute on Aging’s Health ABC study, Chen and his research team reviewed information from almost 2,300 participants between 71 and 82 years old over a 13-year period. Participants included men and women, black and white, who completed a smell test of 12 common odors. Researchers then classified participants as having good, moderate, or poor sense of smell.
“Incorporating a sense of smell screening in routine doctor visits might be a good idea at some point.”
Compared with older adults with a good sense of smell, those with poor smell were at a 46 percent higher risk for death at 10 years and 30 percent at 13 years.
Sex, race, or other demographic and lifestyle factors had minimal effects on the results. However, the surprising revelation was that the healthier participants at the start of the study were found to be largely responsible for the higher risk.
Poor sense of smell is known as an early sign for Parkinson’s disease and dementia and is associated with weight loss. However, these conditions only explained 28 percent of the increased risk, leaving most of it unexplained.
“We don’t have a reason for more than 70 percent of the increased risk. We need to find out what happened to these individuals,” says Chen, who plans to pursue the mystery in future studies.
He adds that poor sense of smell may be an early and sensitive sign for deteriorating health before it’s even recognized in the doctor’s office.
“It tells us that in older adults, impaired sense of smell has broader implications of health beyond what we have already known,” Chen says. “Incorporating a sense of smell screening in routine doctor visits might be a good idea at some point.”
So, what should people do if they think they’re having trouble smelling? Talk to a doctor. “It’s always prudent to talk to a physician about your health concerns,” he says.
The research appears in the Annals of Internal Medicine.
Source: Michigan State University