Arvo building, auditorium F114, address: Lääkärinkatu 1
Doctoral defence of M.Sc. Inna Lisko
The field of science of the dissertation is gerontology science.
The opponent is professor Marjolein Visser (Vrije Universiteit Amsterdam, The Netherlands). Professor Marja Jylhä acts as the custos.
The language of the dissertation defence is English.
Obesity in old age: A bad or good thing?
Low body weight is a greater concern in terms of mortality than general obesity among 90-year-old persons. However, a central finding from the doctoral study was that abdominal obesity was associated with both mortality and low physical functioning especially among women.
Evidence on the adverse health effects of obesity is strong until middle-age. However, in many studies on older adults, mortality risk has shown to be higher among overweight and obese persons than among normal weight persons. On the other hand, obesity is associated with low physical functioning in both younger and older adults. Yet there is only scarce data on the association of obesity with mortality and physical functioning among the oldest old, i.e., persons aged 85 years and older who are the fastest growing segment of the population in the developed countries.
The aim of the doctoral study was to examine the associations of both low and high body weight with physical functioning and mortality in the oldest old, with body mass index (BMI) indicating general obesity and waist circumference indicating abdominal obesity. Furthermore, the aim was to investigate the combined associations of obesity and inflammatory status on mortality in the oldest old. Data for the study were derived from the Vitality 90+ Study, including 596 participants living in the city of Tampere, Finland.
The study showed that among women, the longest survival was among those who had a low waist circumference combined with overweight (BMI 25.0‒29.9 kg/m2) or low inflammation, indicating low disease burden. The number of men was low in these examinations but among them normal weight (BMI 18.5‒24.9 kg/m2) and low waist circumference were associated with an increased mortality risk regardless of inflammation.
Women who had a large waist circumference, often had poor physical functioning. However, among those who had good physical functioning, general obesity or abdominal obesity did not predict the development of disability. Among women, it was rather those who had a low waist circumference that developed disability in activities of daily living.
The results of this doctoral study emphasize the risks associated with low body weight. In the health care and health services, malnutrition and low protein intake should be screened more and nutritional care provided when needed.
The dissertation is published in the publication series of Acta Universitatis Tamperensis; 2267, Tampere University Press, Tampere 2017. The dissertation is also published in the e-series Acta Electronica Universitatis Tamperensis; 1768, Tampere University Press 2017.