High occurrence of transportation and logistics occupations among vascular dementia patients: an observational study

Abstract

Background: Growing evidence suggests a role of occupation in the emergence and manifestation of dementia. Occupations are often defined by complexity level, although working environments and activities differ in several other important ways. We aimed to capture the multi-faceted nature of occupation through its measurement as a qualitative (instead of a quantitative) variable and explored its relationship with different types of dementia.

Methods: We collected occupational information of 2121 dementia patients with various suspected etiologies from the Amsterdam Dementia Cohort (age 67 ± 8, 57% male; MMSE 21 ± 5). Our final sample included individuals with Alzheimer's disease (AD) dementia (n = 1467), frontotemporal dementia (n = 281), vascular dementia (n = 98), Lewy body disease (n = 174), and progressive supranuclear palsy/corticobasal degeneration (n = 101). Within the AD group, we used neuropsychological data to further characterize patients by clinical phenotypes. All participants were categorized into 1 of 11 occupational classes, across which we evaluated the distribution of dementia (sub)types with χ² analyses. We gained further insight into occupation-dementia relationships through post hoc logistic regressions that included various demographic and health characteristics as explanatory variables.

Results: There were significant differences in the distribution of dementia types across occupation groups (χ² = 85.87, p < .001). Vascular dementia was relatively common in the Transportation/Logistics sector, and higher vascular risk factors partly explained this relationship. AD occurred less in Transportation/Logistics and more in Health Care/Welfare occupations, which related to a higher/lower percentage of males. We found no relationships between occupational classes and clinical phenotypes of AD (χ² = 53.65, n.s.).

Conclusions: Relationships between occupation and dementia seem to exist beyond the complexity level, which offers new opportunities for disease prevention and improvement of occupational health policy.

Keywords: Alzheimer’s disease; Occupation; Sex; Vascular dementia; Vascular risk factors.

Fig. 1

Flow diagram of the study sample. ADC, Amsterdam Dementia Cohort; BRC 2014, Dutch ROA-CBS 2014 occupational categorization system, a derivative of the Standard Classification of Occupations 2008 (ISCO 2008); ICT, Information and Communication Technology

Fig. 2

Proportions of dementia types for each occupational class. AD, Alzheimer’s disease dementia; FTD, frontotemporal dementia; VaD, vascular dementia; DLB, Lewy body disease; PSP, progressive supranuclear palsy; CBD, corticobasal degeneration. *χ² adjusted residual ≤ − 2 or ≥ 2 (corresponding to p < .05), ***χ² adjusted residual ≤ − 3 or ≥ 3 (corresponding to p < .001)

Fig. 3

The mean number of vascular risk factors and male percentage for occupational classes and dementia types. Error bars represent standard errors. AD, Alzheimer’s disease dementia; FTD, frontotemporal dementia; VaD, vascular dementia; DLB, Lewy body disease; PSP, progressive supranuclear palsy; CBD, corticobasal degeneration; VRF, vascular risk factors, including included body mass index (BMI), smoking, alcohol use (units per day), and presence or absence of a myocardial infarction, hypertension, hypercholesterolemia, and diabetes mellitus in the medical history