Forskningsartikler

Background: Several modifiable lifestyle risk factors for dementia have been identified, but it is unclear how much the Norwegian public knows about the relationship between lifestyle and brain health. Therefore, this study aimed to investigate knowledge about modifiable dementia risk and protective factors and beliefs and attitudes towards dementia and dementia risk reduction in a randomly selected subsample of the Norwegian population.
Methods: The total sample (n = 1435) included individuals aged 40-70 years from four counties (Oslo, Innlandet, Nordland and Trøndelag) in Norway. Two online questionnaires were used to measure (1) awareness about dementia risk reduction and (2) an individual`s motivation to change behaviour for dementia risk reduction (MOCHAD-10).
Results: Of the participants, 70% were aware of the potential of dementia risk reduction in general. Physical inactivity (86%), cognitive inactivity (84%) and social isolation (80%) were the most frequently recognised dementia risk factors. On the other hand, diabetes (26%), coronary heart disease (19%), hearing loss (18%) and chronic kidney disease (7%) were less often recognised as dementia risk factors. Comparing men and women, the only significant difference was that women were more likely to report parents with dementia as a risk factor compared to men. Gender, age and educational differences were seen in beliefs and attitudes towards dementia prevention:women reported more negative feelings and attitudes towards dementia than men;those aged 40-49 years – more likely than older age groups – reported that ‘knowing family members with dementia’ or ‘having risk factors’ made them believe they had to change their lifestyle and behaviour.
Conclusions: The results indicate that 70% of the Norwegian public are aware of the potential for dementia risk reduction in general. However, there are major gaps in existing knowledge, particularly for cardiovascular risk factors such as hypertension, coronary heart disease, hypercholesterolemia and metabolic factors (diabetes, obesity). These findings underline the importance of further informing the Norwegian public about lifestyle-related risk and protective factors of dementia. Differences in beliefs and attitudes towards dementia risk prevention by age, gender and education require tailored public risk reduction interventions.

Grete Kjelvik, Anne Marie Mork Rokstad, Josephine Stuebs, Pernille Thingstad, Kay Deckers, Sebastian Köhler, Geir Selbæk

Objectives: Earlier studies suggest that being married in later life protects against dementia, and that being single in old age increases the risk of dementia. In this study, we examine midlife marital status trajectories and their association with dementia and mild cognitive impairment (MCI) at ages 70 plus using a large population based sample from Norway.
Methods: Based on a general population sample linked to population registries (N = 8706), we used multinomial logistic regression to examine the associations between six types of marital trajectories (unmarried, continuously divorced, intermittently divorced, widowed, continuously married, intermittently married) between age 44 and 68 years from national registries and a clinical dementia or a MCI diagnosis after age 70. We estimated relative risk ratios (RRR) and used mediation analyses adjusting for education, number of children, smoking, hypertension, obesity, physical inactivity, diabetes, mental distress, and having no close friends in midlife. Inverse probability weighting and multiple imputations were applied. The population attributable fraction was estimated to assess the potential reduction in dementia cases due to marital histories.
Results: Overall, 11.6% of the participants were diagnosed with dementia and 35.3% with MCI. Dementia prevalence was lowest among the continuously married (11.2%). Adjusting for confounders, the risk of dementia was higher for the unmarried (RRR = 1.73; 95% CI: 1.24, 2.40), continuously divorced (RRR = 1.66; 95% CI: 1.14, 2.43), and intermittently divorced (RRR = 1.50; 95% CI: 1.09, 2.06) compared to the continuously married. In general, marital trajectory was less associated with MCI than with dementia. In the counterfactual scenario, where all participants had the same risk of receiving a dementia diagnosis as the continuously married group, there would be 6.0% fewer dementia cases.
Discussion: Our data confirm that staying married in midlife is associated with a lower risk of dementia and that divorced people account for a substantial share of dementia cases.

Vegard Skirbekk, Catherine E Bowen, Asta Håberg, Astanand Jugessur, Bo Engdahl, Bernt Bratsberg, Ekaterina Zotcheva, Geir Selbæk, Hans-Peter Kohler, Jordan Weiss, Jennifer R Harris, Sarah E Tom, Steinar Krokstad, Yaakov Stern, Bjørn Heine Strand

Background and objectives: Impaired spatial navigation is considered an early sign in many neurodegenerative diseases. We aimed to determine if spatial navigation was associated with future dementia in patients with subjective cognitive decline (SCD) or mild cognitive impairment (MCI), and to explore associations between spatial navigation and biomarkers of Alzheimer’s disease (AD) and neurodegeneration.

Methods: The study included memory clinic patients without dementia in the longitudinal BioFINDER cohort. The Floor Maze Test (FMT) was used to assess spatial navigation at baseline. Conversion to dementia were evaluated at 2- and 4-year follow-ups. At baseline, amyloid-β 42/40 ratio, phosphorylated-tau (p-tau) and neurofilament light (NfL) were analysed in CSF. Cortical thickness and volume of regions relevant for navigation, and white matter lesion volume were quantified from MRI. The predictive role of the FMT for conversion to all-cause dementia was analysed using logistic regression analyses in two models; 1) controlled for age, sex and education, and 2) adding baseline cognitive status and MMSE. Associations between FMT and biomarkers were adjusted for age, sex, and cognitive status (SCD or MCI).

Results: 156 patients with SCD and 176 patients with MCI were included. FMT total time was associated with progression to all-cause dementia in model 2 at 2-year (OR 1.10, 95% CI 1.04, 1.16) and at 4-year follow-up (OR 1.10, 95% CI 1.04, 1.16), i.e., a 10 % increase in odds of developing dementia per every 10 sec increase in FMT. In the adjusted analyses, P-tau and NfL was associated with FMT total time, as well as hippocampal volume, parahippocampal and inferior parietal cortical thickness. Amyloid-β 42/40 ratio was not associated with FMT total time.

Discussion: Impaired spatial navigation was associated with conversion to dementia within 2 and 4 years, and with key CSF and MRI biomarkers for AD and neurodegeneration in patients with SCD and MCI. This supports its use in early cognitive assessments, but the predictive accuracy should be validated in other cohorts.

Classification of evidence: This is a Class 1 prospective cohort study demonstrating association of baseline markers of spatial recognition with development of dementia in patients with SCD or MCI at baseline.

Gro Gujord Tangen, Maria H Nilsson, Erik Stomrud, Sebastian Palmqvist, Oskar Hansson