Higher industriousness was associated with a 25% reduced risk of concurrent motoric cognitive risk syndrome (MCR), based on data from approximately 6,000 individuals.
Previous research supports an association between conscientiousness and a lower risk of MCR, a form of predementia that involves slow gait speed and cognitive complaints, wrote Yannick Stephan, PhD, of the University of Montpellier (France), and colleagues. However, the specific facets of conscientiousness that impact MCR have not been examined.
In a study published in the Journal of Psychiatric Research, the authors reviewed data from 6,001 dementia-free adults aged 65-99 years who were enrolled in the Health and Retirement Study, a nationally representative longitudinal study of adults aged 50 years and older in the United States.
Baseline data were collected between 2008 and 2010, and participants were assessed for MCR at follow-up points during 2012-2014 and 2016-2018. Six facets of conscientiousness were assessed using a 24-item scale that has been used in previous studies. The six facets were industriousness, self-control, order, traditionalism, virtue, and responsibility. The researchers controlled for variables including demographic factors, cognition, physical activity, disease burden, depressive symptoms, and body mass index.
Overall, increased industriousness was significantly associated with a lower likelihood of concurrent MCR (odds ratio, 0.75) and a reduced risk of incident MCR (hazard ratio, 0.63,; P < .001 for both).
The conscientiousness facets of order, self-control, and responsibility also were associated with a lower likelihood of both concurrent and incident MCR, with ORs ranging from 0.82-0.88 for concurrent and HRs ranging from 0.72-0.82 for incident.
Traditionalism and virtue were significantly associated with a lower risk of incident MCR, but not concurrent MCR (HR, 0.84; P < .01 for both).
The mechanism of action for the association may be explained by several cognitive, health-related, behavioral, and psychological pathways, the researchers wrote. With regard to industriousness, the relationship could be partly explained by cognition, physical activity, disease burden, BMI, and depressive symptoms. However, industriousness also has been associated with a reduced risk of systemic inflammation, which may in turn reduce MCR risk. Also, data suggest that industriousness and MCR share a common genetic cause.
The study findings were limited by several factors including the observational design and the positive selection effect from patients with complete follow-up data, as these patients likely have higher levels of order, industriousness, and responsibility, the researchers noted. However, the results support those from previous studies and were strengthened by the large sample and examination of six facets of conscientiousness.
“This study thus provides a more detailed understanding of the specific components of conscientiousness that are associated with risk of MCR among older adults,” and the facets could be targeted in interventions to reduce both MCR and dementia, they concluded.
The Health and Retirement Study is supported by the National Institute on Aging and conducted by the University of Michigan. The current study was supported in part by the National Institutes of Health. The researchers had no financial conflicts to disclose.