Dr Katya Numbers

1. Dementia prevention is the primary focus of my research and a national health care priority in Australia. Although dementia is the second leading cause of death in older Australians, it is estimated that 40% of all dementia cases are preventable through the modification of lifestyle risk factors such as social isolation, diet, and exercise. This is where my research comes in. Specifically, I investigate the mediating role of depression and anxiety on risk factors associated with dementia. Previously it was assumed that the presence of increased neuropsychiatric symptoms in people with dementia was a result of the disease (e.g., increasing loss of autonomy), but it is now known that chronic psychiatric symptoms can play a causative role in the development of dementia pathology; for instance, changes in cortisol associated with depression and anxiety also impacts grey matter brain volumes implicated in many dementias (i.e., hippocampus and prefrontal cortex).

2. My second area of research focus is the intersection between older adults’ subjective experiences of cognitive decline and functional ability and their risk for future dementia. This is an especially important area of ageing and dementia research given subjective cognitive complaints (SCCs) are now considered a very early pre-clinical stage of dementia, meaning SCCs are an important diagnostic tool to facilitate early intervention programs. My recent research examines temporal changes in participant and informant SCCs using latent growth curve analyses to model linear changes in SCC reporting over time. I also examine the relationship between self-report and informant-report (someone who knows the person well) SCCs and utility in predicting dementia. 

3. My research also promotes healthy ageing by supporting individuals with dementia. Unfortunately, all dementias are progressive. However, this should not deny personhood or a maximised quality of life people living with dementia or their care partners. This has become especially relevant in light of the current COVID-19 pandemic and ensuing periods of prolonged lockdowns, which have disproportionately impacted older adults worldwide. I have been heavily involved in research looking at the impact of COVID-19 and social isolation on older adults with and without with dementia. I developed and administered a CHeBA COVID-19 questionnaire to over 400 participants (aged 65 – 103) in 2020, and have collected administered the same questionnaire to older German participants to examine cohort and geographic impacts of the pandemic. I am also an Investigator on a 3-country grant that is harmonising data across Australia, the UK, and the US, to determine factors associated with post-COVID wellbeing in older adults on several dimensions.

4. Finally, I am very actively involved in research and groups that aim to challenge negative stereotypes about ageing and dementia. A compelling body of data has emerged showing negative attitudes towards ageing pose a significant risk to physical health and psychological well-being in later life. For example, older adults with worse attitudes about ageing have poorer physical, cognitive, and mental health, and studies show that individuals who endorse negative ageing attitudes in midlife (~45 years) are at greater risk of developing cardiovascular and Alzheimer’s disease pathology nearly 20 years later (~65 years). Not only do negative ageing attitudes predict worse health outcomes in older adults, but ageism promotes other forms of discrimination including social exclusion from important roles and relationships, which further fosters feelings of isolation and loneliness. This is important because increased isolation and loneliness are related to increased neuropsychiatric symptoms such as depression and anxiety, which in turn can result in cortisol related brain pathology.