Poor Sense of Smell Linked to 50 Percent Higher Mortality Risk

We know that body function declines as we age but a new study warns that a poor sense of smell could be a sign of pending death within the next ten years.  While the study examined this trend occurs among older adults, the surprising data suggests that it could be true even among those who are healthy.

According to epidemiologist—and elderly sensory deficit expert—Honglei Chen, “Poor sense of smell becomes more common as people age.  Our study is the first to look at the potential reasons why it predicts a higher mortality.”

The study reviewed data collected in the National Institute on Aging’s Health ABC study.  Chen and his team looked at information taken from 2,300 participants between the ages of 71 and 82, over a period of 13 years.  Each person completed a smell test of 12 of the most common odors, from which researchers participants were classified as having good or moderate or poor olfactory sense. 

When comparing the results, then, the researchers say that older adults with a poor sense of smell had a 46 percent increased risk for death within 10 years.  They also had a 30 percent higher risk of death within 13 years. 

It should be noted that the results of the study were only marginally affected by demographic factors like sex, race, and lifestyle variables. However, it was surprising that those who were healthier at the start of the study period appeared to be at the greatest risk. 

Now, declining sense of smell is already known to be an early sign of both Parkinson’s disease and dementia. Again, Chen: “It tells us that in older adults, impaired sense of smell has broader implications of health beyond what we have already known. Incorporating a sense of smell screening in routine doctor visits might be a good idea at some point.”

At the same time, though, is also associated with weight loss; but these conditions only seem to be linked to a 28 percent higher risk for death.

Indeed, Chen notes, “We don’t have a reason for more than 70% of the increased risk. We need to find out what happened to these individuals,” adding that they plan to continue pursuing this avenue of investigation in the future. 

The results of the study have been published in the journal Annals of Internal Medicine.