Does decline in cardiovascular risk factor levels also have an impact on the age‐specific cognitive function of older adults over time? A comparison of a repeated cross‐sectional panel study in the same population over 14 years

• Published in: Alzheimer's & Dementia
• Main Authors: Johnsen, Bente, Schirmer, Henrik, Martinatyte, Ieva, Strand, Bjørn Heine
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 2020
• Subjects: Tromsø
• Online Access: http://dx.doi.org/10.1002/alz.040790; https://onlinelibrary.wiley.com/doi/pdf/10.1002/alz.040790; https://onlinelibrary.wiley.com/doi/full-xml/10.1002/alz.040790

Abstract Background Research suggests that cardiovascular risk factors have an impact on cognitive function and development of dementia. We lack evidence that cognitive function is actually improving in the population, as the risk factors decrease. We aim to see if the dementia‐free population of Tromsø has improved cognition over time and if so which changes are associated with improved cognition. Method The Tromsø Study is an ongoing large, prospective population based cohort study. Cognitive measures was included from 2001 and repeated in 2008 and 2015. Only participants in the ages of 60‐88 were included. A total of 5173 women and 4341 men did at least one cognitive test during these three waves. Age groups were stratified to 60‐66 years, 66‐73 years, 74‐80 years and 80‐88 years. The cognitive tests were Word test 1 (12‐word immediate recall), Word test 2 (recognition), Digit‐Symbol Coding and Tapping test.All participants also filled out an extensive questionnaire, had blood samples and anthropomorphic measures taken.Difference between screenings in all cognitive tests were analysed in Stata using sex specific linear regression. The results were then adjusted for age, education, blood pressure, smoking, hypercholesterolemia, previous heart attack, previous stroke, diabetes, depression, activity levels, alcohol consumption and BMI. The explanatory variables were tested to see how much they accounted for a change in the beta coefficient when added. Result The cognitive tests show a significant improvement in cognitive function in age specific groups in 2015, compared to 2001. This improvement is present in all age groups. (p < 0,001 for all age groups) The factors that contribute most to the improvement is alcohol consumption (15,2 % men, 20 % women), increased education (44,7 % men and 39,5 % women) and physical activity (10,7 % men and 12,8 % women). Other cardiovascular risk factors had little to no impact. Conclusion Cognitive function improves in older adults consistently in four cognitive tests ...