Association of mood disorder and bone health with cognitive function among healthy ageing men

AbstractBackgroundHigh dementia prevalence and associated disability have necessitated a focus on the identification of potentially modifiable risk factors. Mental and physical health conditions such as mood disorder and bone loss have been previously linked with poor cognition although their combined effect remains largely unknown.1 We investigated whether an interaction between mood disorder and bone loss is associated with cognitive function in a population‐based sample of men.MethodParticipants free from severe cognitive impairment were drawn from the Geelong Osteoporosis Study (n = 442, mean age = 63.5 years) and cognition was assessed via the CogState Brief Battery that measured performance across four domains (psychomotor function, attention, learning and working memory).2 Mood disorder and hip bone mineral density (BMD) were evaluated using a semi‐structured clinical interview and dual‐energy x‐ray absorptiometry, respectively. Linear regression analyses adjusted for age, education, SES, mobility, smoking status, alcohol consumption and APOE ε4 status were conducted to investigate whether lifetime history of a mood disorder, hip BMD or two‐way interaction are associated with overall cognitive function and cognitive performance in individual domains.ResultHip BMD (Bcoeff 0.56 95% CI 0.07, 1.05) but not mood disorder (Bcoeff ‐0.50 95% CI ‐0.20, 0.10) was associated with overall cognitive function after accounting for potential confounders. Significant interaction effects were observed between the two exposures (Bcoeff ‐1.37 95% CI ‐2.49, ‐0.26) suggesting that individuals without a mood disorder displayed better overall cognitive performance with increasing BMD, whereas those with a lifetime history of mood disorder displayed poorer cognitive function with increasing BMD. Interaction effects were also observed for the individual cognitive domains (Fig. 1). Results remained virtually unchanged when mood disorder was limited to major depressive disorder.ConclusionThis is the first‐ever study that reported an interaction between mood disorder and BMD that could be accounted for in establishing risk factors for cognitive decline.1. Mehta K, Thandavan SP, Mohebbi M, Pasco JA, Williams LJ, Walder K, et al. Depression and bone loss as risk factors for cognitive decline: A systematic review and meta‐analysis. Ageing Res Rev 2022; 76: 101575.2. Pasco JA, Nicholson GC, Kotowicz MA. Cohort profile: Geelong Osteoporosis Study. Int J Epidemiol 2012; 41: 1565‐75.