Higher risk for both mental and physical health issues has been found for people from sexual minorities (SM), i.e. non-heterosexual people. According to the “minority stress model”, these health inequalities have been hypothesised to be consequences of sexual orientation-related stigma and the resulting conditions of chronic stress. The impact of minority stress may be particularly detrimental in SM older people and may potentially foster a decline in cognitive functions, such as memory and attention. A handful of retrospective studies attempted to address this issue, but with several limitations regarding study design and lack of data on sexual orientation, cognitive performance and potential risk factors. Therefore, to date, it is unclear whether stigma and health problems may affect the brain and cognitive performance of SM older people and potentially lead to cognitive impairment over time.
The overall aim of this project funded by the Alzheimer's Association is to investigate how measures of stigma and mental health problems contribute to the neurocognitive decline in SM older adults by leveraging existing large databases and by collecting cognitive, brain imaging (MRI) and detailed stigma-related data in a new cohort. These will be used to predict differences, both cross-sectionally and longitudinally, in cognition and cerebral features between heterosexual and non-heterosexual older adults. This project aims to overcome the limitations and inconsistencies currently observed in this emerging field of research by introducing a series of methodological advancements. First, two large UK-based datasets including data on sexual orientation of older adults will be used to investigate potential differences in longitudinal cognitive and brain decline between heterosexual and non-heterosexual older adults aged 60 and above.
These will be the first studies on longitudinal changes in cognition and brain parameters in this minority population by including a comprehensive range of cognitive tests and multimodal brain MRI data. Moreover, the hypothesised impact of stigma and mental health problems on longitudinal neurocognitive decline in SM older adults will be tested for the first time. Finally, novel detailed stigma-related data will be collected using previously validated scales to test whether different dimensions of minority stress predict neurocognitive health in SM older adults.
This project will contribute to quantify the impact of psycho-social risk factors, in particular sexual orientation-related stigma and mental health problems, for brain and cognitive health in the non-heterosexual older people. The findings of this project will increase our understanding of the specific risk factors for cognitive decline/dementia and the associated neural changes in this minority group. It is possible that similar psycho-social factors may be shared by other minority groups, e.g. ethno-racial minorities. Therefore, such insight can potentially improve diversified participant recruitment for clinical trials and enable a “precision medicine” approach to plan therapeutic interventions (both pharmacological and non-pharmacological) meeting specific needs of people from sexual and other minority groups experiencing cognitive decline. Moreover, the findings of this project will offer new useful data to inform policy makers about the additional risks for cognitive decline in this understudied population.