Reduced physical activity reduces life span

The Monash University-led study examined the significance of weight and physical function and the interaction on mortality in 1435 men and women aged 65 to 97 years, living in the community and representative of the Taiwanese population.

The results of the eight-year study were recently published in the Journal of Nutrition, Health and Aging. The study also included researchers from the National Health Research Institutes, Taiwan and the National Defense Medical Centre, Taiwan.

Lead author, Emeritus Professor Mark Wahlqvist from Monash University's Department of Epidemiology and Preventive Medicine and the Monash Asia Institute, said being frail or losing weight was generally regarded as a major risk for reduced survival among the elderly.

"We found thin, elderly Taiwanese with sarcopenia – a condition of age-related loss of muscle mass and strength - and less skeleton are at the most risk of death, especially if physical function is limited. Those within the normal weight range or even overweight and active had a longer life expectancy with fewer health problems," Emeritus Professor Wahlqvist.

Survival was assessed in relation to weight and body composition, along with physical function such as walking, climbing, performing daily chores and personal care.

The researchers found weight in relation to height (body mass index (BMI) = weight/height2) was twice as likely to shorten the survival of the elderly when low (BMI < 18.5) than high (above 24.0). This increased to nine times more likely when combined with limited physical function. The findings took into account factors such as age, gender, socio-economics and personal behaviours that could have explained the association.

Emeritus Professor Wahlqvist said although this was not an intervention study, it raised the possibility that if physical function could be maintained, then mortality could be markedly reduced in this older age group.

"In light of these figures, both those in public health and clinicians need to look at preventive approaches or intervention strategies that might achieve better survival in older people in regard to thinness and physical dysfunction," Emeritus Professor Wahlqvist said.

"Even small changes involving modest regular physical aerobic and strengthening activities for several days a week could make a substantial difference in health outcomes for the elderly."

More information: DOI: 10.1007/s12603-012-0379-3

Provided by Monash University