Forskningsartikler

Abstract:

The cerebellum has been linked to motor coordination, cognitive and affective processing, in addition to a wide range of clinical illnesses. To enable robust quantification of individual cerebellar anatomy relative to population norms, we mapped the normative development and aging of the cerebellum across the lifespan using brain scans of > 54k participants. We estimated normative models at voxel-wise spatial precision, enabling integration with cerebellar atlases. Applying the normative models in independent samples revealed substantial heterogeneity within five clinical illnesses: autism spectrum disorder, mild cognitive impairment, Alzheimer’s disease, bipolar disorder, and schizophrenia. Notably, individuals with autism spectrum disorder and mild cognitive impairment exhibited increased numbers of both positive and negative extreme deviations in cerebellar anatomy, while schizophrenia and Alzheimer’s disease predominantly showed negative deviations. Finally, extreme deviations were associated with cognitive scores. Our results provide a voxel-wise mapping of cerebellar anatomy across the human lifespan and clinical illnesses, demonstrating cerebellum’s nuanced role in shaping human neurodiversity across the lifespan and in different clinical illnesses.

Milin Kim, Esten Leonardsen, Saige Rutherford, Geir Selbæk, Karin Persson, Nils Eiel Steen, Olav B. Smeland, Torill Ueland,  Geneviève Richard, Christian F. Beckmann, Andre F. Marquand, Alzheimer’s Disease Neuroimaging Initiative (ADNI), Ole A. Andreassen,  Lars T. Westlye, Thomas Wolfers & Torgeir Moberget

Background: Even if olfactory training (OT) is a well-established treatment for individuals with olfactory dysfunction, the effect on individuals with normosmia remains uncertain. In this randomised controlled trial, we explore how OT with different exposure lengths affect olfactory function in individuals with normosmia.

Methodology: Two hundred normosmic individuals were randomly assigned to one of two intervention groups performing OT with different exposure lengths or to a control group. The OT groups did OT twice daily for three months, sniffing four different odours (eucalyptus, lavender, mint, and lemon) for 10 seconds per bottle during either a total of 40 seconds (standard OT) or 4 minutes (extended OT), while the control group did not perform any OT. Olfactory function was assessed using a 48-item Sniffin Sticks test at baseline, after the intervention, and after one year.

Results: We found no significant effect of OT in either of the intervention groups on any aspect of olfaction after intervention or at follow-up. There was no association between sex, age, allergic rhinitis, education or olfactory scores at baseline, and changes in olfactory function after OT. The extended OT group performed significantly fewer training sessions compared to those in the standard OT group.

Conclusions: OT had a limited effect on olfactory function in individuals with normosmia. Further, the superiority of a more extended OT is not supported by this study, and shorter training sessions seem to improve compliance with OT.

Ingrid Torvik Heian, Wenche Moe Thorstensen, T A Myklebust, Thomas Hummel, Ståle Nordgård, Mette Bratt & Anne Helvik

Background: The prevalence of dementia in nursing home (NH) residents is high, and pain is a troublesome symptom for them. Several studies since 2010 have focused on pain in NH residents with dementia, but there is a lack of systematic reviews on the prevalence of pain in NH residents with dementia.

Aim: To systematically review observational studies published from 2010 to 2023 on how pain is assessed and prevalence of pain found in NH residents with dementia.

Methods: A systematic search was conducted in the MEDLINE, PubMed, PsycINFO, Embase, CINAHL, AgeLine, and Cochrane databases for studies published from January 2010 to August 2023. Studies were included if they were observational studies with a quantitative design where self-report, staff assessment, and/or chart review were used to define the prevalence of pain in samples or subsamples of NH residents with dementia.

Results: Of 184 studies considered, 25 were included. The studies assessed pain as daily, present, clinically relevant, chronic, intermittent, persistent pain and/or if pain affected quality of life. The prevalence of pain was high in most studies of NH residents with dementia independent of whether pain was reported as presence of pain or clinically relevant pain, but the prevalence varied from 8.6% to 79.6%. This prevalence was quite stable across the NH stay, but higher towards the end of life (up to 80.4%). Study designs and methodologies differed considerably. About half relied on an observational assessment inventory.

Conclusion: The number of studies focusing on pain in NH residents with dementia was restricted and methodologies differed considerably. Relatively few studies used an observational assessment inventory. In view of the fact that residents with dementia may have difficulties communicating pain, clinicians should pay attention to pain in these residents, systematically and reliably uncover pain by use of observational inventories, and subsequently treat pain to secure high quality care.

Anne-S Helvik, Sverre Bergh & Kjerstin Tevik