Loss of Sense of Smell May Indicate Higher Risk of Heart Failure: Study

Specialists estimate that about 64 million people globally have heart failure — a medical condition where the heart is unable to pump enough blood throughout the entire body. Now researchers from Michigan State University say losing the sense of smell may help predict a person’s risk of developing heart failure. 

The study was recently published in the Journal of the American Heart Association. People begin to lose their sense of smell as they age, and previous research shows olfactory dysfunction begins to increase once we hit age 60. Smell loss or impairment affects about a quarter of older adults. Public awareness is low though — only about 30% of those with smell loss know they have it. 

Researchers learned in the past two decades that smell loss is one of the most important early markers of dementia and Parkinson’s disease. Interestingly, emerging data, including ours, suggests that smell loss may have more profound implications on the health of older adults, including the risk of death. 

Smell loss may also be related to cardiovascular health for example, preliminary data found that subclinical cardiovascular changes may affect the sense of smell of older adults. Participants who first enrolled in this study in 1997 and 1998 were healthy older adults between the ages of 70 and 79. 

Study participants were followed starting from the time their sense of smell was tested at a clinic visit in 1999 or 2000 for up to 12 years or until they had a cardiovascular event or passed away. 

Scientists were analyzing the data to see if they could find a link between loss of smell and cardiovascular conditions including heart attack, stroke, congestive heart failure, angina, or death caused by coronary heart disease. 

At the study’s conclusion, researchers found participants with olfactory loss had about a 30% increased risk of developing congestive heart failure compared to those who did not lose their sense of smell. The study authors also reported finding no link between olfactory loss and heart disease or stroke. 

Besides atherosclerosis, other myocardial stressors can also trigger heart failure hospitalization. Smell loss may signify higher vulnerability to myocardial stressors beyond atherosclerosis. Nevertheless, the findings are preliminary, waiting for confirmation. This association found in the research may simply be due to an aging body developing both conditions concurrently. Future research in this area should focus on validating a relationship between the sense of smell and heart failure with larger studies preferably with longitudinal assessment of olfaction. In addition, the potential underlying mechanisms for such a relationship should be studied.