A natural decline of the five classical senses - vision, hearing, taste, smell and touch -- can predict a number of poor health outcomes, including greater risk of death, says a study.
"We can now predict how changes in our senses can influence activities we think are really important, like walking, moving, and living," said lead researcher Jayant Pinto, Professor of Surgery at the University of Chicago.
The study spanning five years and including more than 3,000 US adults aged 57-85 began with an assessment of how sensory dysfunction affected their physical and cognitive abilities.
The research team found that adults with worse sensory dysfunction moved slower and had greater difficulty performing daily activities.
Five years later, the same people had a more sensory impairment. They moved even slower, were less active, and had more physical and cognitive disabilities. Compared to those with less sensory impairment, they had a higher risk of dying, said the study published online in the Journal of the American Geriatrics Society.
"This is the first study to show that decreased sensory function of all five senses can be a significant predictor of major health outcomes," said Martha McClintock, Professor at the University of Chicago.
In the study, the researchers used validated tools and controlled for factors that could affect the results such as demographics, education level, drug and alcohol use, and weight.
The researchers also teased apart any sensory loss that was due to environmental factors, such as exposure to loud noises that cause poor hearing. This allowed them to measure sensory impairment as a function of ageing alone.
Sensory impairment can add insight into the mechanisms that drive health outcomes associated with ageing.
"There appears to be one or more specific physiological processes of ageing - so far unidentified - that account for how the five senses decline together," Pinto said.
