Modifiable Risk Factors for Accelerated Decline in Processing Speed: Results from Three Dutch Population Cohorts.

BACKGROUND: Several lifestyle, cardiovascular and psychosocial factors are associated with risk of cognitive decline and dementia. We studied the independent associations of a broad set of modifiable risk factors with decline in processing speed in three large population-based cohorts with up to 23 years of follow-up. METHODS: We used data of 9,666 participants from the Doetinchem Cohort Study, the Longitudinal Aging Study Amsterdam, and the Maastricht Aging Study. Decline in processing speed was measured with the letter digit substitution task or the alphabet coding task and modeled using quadratic latent growth curves. Associations of modifiable risk factors with level and rate of decline in processing speed were investigated by estimating associations with level of processing speed at different centering ages. RESULTS: Latent growth curves showed that decline in processing speed accelerated with age. Smoking, not drinking alcohol and depressive symptoms were associated with a lower level of processing speed in all cohorts. In two of the cohorts, more physical activity, drinking more than two glasses of alcohol per day, higher BMI and diabetes were associated with a lower level of processing speed. Depressive symptoms and diabetes were also associated with faster decline in processing speed. CONCLUSION: Several modifiable risk factors are associated with the level of processing speed in older age, while few are also related to the rate of decline.

[Socio-economic position: more than a background characteristic in psychiatry]. / Sociaal-economische positie: méér dan een achtergrondkenmerk in de psychiatrie.

Background Mental illness is more common and has a less favorable course in people with a low socioeconomic position (SEP). Aim To clarify the concept of SEP and what mechanisms underlie socioeconomic differences in mental illness. Method Review of theoretical and empirical scientific research. Results For determining socioeconomic differences in mental illness, it matters whether one looks at educational level, occupational level, or income. Mechanisms of social causation and social selection play a role. Among other mechanisms, SEP contributes to mental illness through exposure to stressors, unfavorable living conditions, unhealthy behaviors, and social exclusion. Conversely, mental health problems can negatively influence SEP. Conclusion Researchers and practitioners should be aware that SEP is more than a background characteristic of a patient or a statistical control variable; over the life course there is a complex interaction between SEP and both the etiology and course of mental illness.