The interrelation between cerebral small vessel disease and domains of functioning in an older memory clinic population: a holistic overview through network analysis

Abstract

Introduction: Research is lacking regarding the effect of cerebral small vessel disease (CSVD) on different domains of functioning and their interrelations. Network analyses provides a holistic overview of interrelationships between different variables. Therefore, we applied network analysis on data of older people with varying levels of CSVD and their cognitive, physical, emotional and daily functioning. Methods: We included participants (n=807) from the Amsterdam Aging Cohort. Inclusions criteria were a memory clinic visit including (i) comprehensive geriatric assessment, (ii) brain imaging and (iii) neuropsychological evaluation.CSVD was operationalized as White Matter Hyperintensities (WMH), according to the Fazekas scale, dividing the sample in three levels: no/mild WMH (Fazekas 0/1), moderate WMH (Fazekas 2) and severe WMH (Fazekas 3)Domains of functioning were operationalized as follows. Physical functioning: gait speed and handgrip strength (HGS). Cognitive functioning: composite z-scores in the domains memory, language, attention/speed and executive functioning. Daily functioning: Katz ADL and the Lawton iADL. Emotional functioning: Geriatric Depression Scale-15, Apathy (GDS-3A) and Depression (GDS-12D) subscales. Health related Quality of Life (hrQoL): EQ5D-VAS. We ran a network (mixed graphical model) to assess the associations between the domains of functioning. We tested whether these associations were different for different levels of CSVD in a moderated network model. Multiple regression, corrected for sex, age and education level, was used to assess the difference in domains of functioning between CSVD levels. Results: In the network model, more depressive and apathy symptoms are associated with lower hrQoL. Lower physical & cognitive functioning are associated with worse daily functioning (Figure). The moderated network did not significantly differ between CSVD levels. Yet, our multiple regression analyses did show differences that WMH severity is related with worse physical functioning, worse daily functioning, lower hrQoL, more apathy symptoms and lower cognitive functioning in the attention and language domains (Table). Discussion: Domains of functioning are highly connected in this older population, while CSVD is associated with worse functioning in all domains. This implicates that cognitive and emotional changes prevalent in CSVD (apathy, reduced speed) co-occur with worse daily functioning and decreased quality of life, warranting a holistic approach in clinical care.