Research Study Identifies Interoception in Elderly Heart Failure Patients

It's fairly common for people to associate a loss of hearing, sight, smell and taste with aging. But a recent research study has found that a loss of touch--and the ability to identify pain or feeling, such as what would be associated with symptom recognition--can also occur as one gets older. And for elderly patients suffering from chronic heart failure, that phenomenon can be especially life-threatening.

The study, Symptom Recognition in Elders with Heart Failure, focused on interoception, the sense of the physiological condition of the body. It was funded by a pilot research grant from the University of Pennsylvania Institute on Aging and authored in part by Barbara Riegel, RN, DNSc, FAAN, FAHA, professor, School of Nursing, University of Pennsylvania, PA.

Making the Connection

"I have a long history of studying heart failure self care," indicates Riegel. "What I found so striking over the course of my nursing career was that sometimes it would be so obvious that a patient had been having trouble for quite some time. Yet they would suddenly end up in the hospital or call 9-1-1, and they were in blatant pulmonary edema. I would think, 'Why didn't they notice they were getting into trouble?'"

After learning about interoception from a colleague, Riegel began to wonder if these patients simply couldn't detect they were in trouble, i.e., their ability to feel pain or notice a symptom associated with their disease had diminished as they aged. "We would have patients come into the hospital who had gained 30 pounds, all due to fluid retention in their ankles," she says. "Yet they didn't indicate they were in any pain, nor did they notice their swollen ankles."

This breakthrough was coupled with her own self-discovery that she couldn't hear, taste or see as well as she once did. "It's common for other areas of sensory perception to decline with age," she says. "Why wouldn't we think the pads on our fingers wouldn't be quite as sensitive, or the ability to sense changes on the inside of our bodies wouldn't be as acute as it was when we were younger?"

Identifying Detection and Interpretation

For the study, researchers divided 29 people who had been diagnosed with chronic heart failure for at least six months into two groups: those who were younger than 73 years old and those who were 73 and older.

Using a six-minute walk test, researchers evaluated each group's ability to detect and interpret their heart failure symptoms by measuring their ability to detect shortness of breath, a common symptom of the disease due to fluid retention and pressure on the lungs.

"For a person who has heart failure, walking quickly will make them short of breath," she says. "We wanted to determine if their responses were a case of not noticing (detection) or simply not wanting to notice their shortness of breath (interpretation). We wanted to sort out if patients were attributing symptoms to aging and just accepting that since they were getting older, these symptoms were what they should expect."

Findings confirmed that older patients did have more difficulty detecting and interpreting shortness of breath than younger patients. In fact, older patients were twice as likely as younger patients to report a different level of shortness of breath than what was noted by researchers.

Although both detection and interpretation differences were noted, detection variances were greater. "There does seem to be a difference in detection," she says. "Some people truly weren't feeling the pain as intensely as someone in their 20s or 30s."

That seems to coincide with what Riegel indicates she's learned from her years of nursing: Elderly patients simply d have as much pain after surgery as their younger counterparts. "Looking back, it was the younger patients who were suffering after surgery," she says. "Their sensory perception is quite acute whereas elderly patients typically don't feel pain as much."

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