Impact of frailty, early vascular decline and subclinical cognitive impairment in midlife adults: study protocol of the Toledo Study for Healthy Ageing in middle age.

Life expectancy has increased worldwide alongside a rise in disability prevalence during old age. The impact and interrelationship among the precursors of disability in midlife remain to be better understood. Furthermore, investigating whether lifestyle factors may potentially influence health outcomes and the prognosis of vascular disease could be especially relevant among the middle-aged population, which is a priority subpopulation when prevention is the goal. This is an observational, cross-sectional and population-based study. Participants, between 50 and 55 years old, are randomly selected from the municipality of Toledo (Spain). There are six non-consecutive days for the assessments, providing enough rest between evaluations. Participants perform the interview of the Toledo Study for Healthy Aging. Blood pressure monitoring and a resting electrocardiogram are also recorded. Then, resting peripheral and cerebral vascular measurements along with muscle size and architecture are assessed. Blood and urine samples, and body composition data are collected after an overnight fasting. On a different visit, physical performance and muscle function tests are performed. Additionally, brain magnetic resonance imaging is conducted. And finally, an accelerometer is given to the participants for a week. Frailty is evaluated by Frailty Trait Scale and Fried Frailty Phenotype. This project will shed light on the associations between frailty, early cognitive impairment, and vascular aging during midlife, and on the role that lifestyles play in their development. Lastly, this project will provide meaningful implications for public health strategies aimed at promoting healthy aging in later life.