Intersectional sociodemographic and neurological relationships in the naming ability of persons with post-stroke aphasia

Introduction

Significant attention has been given to the role of brain function and disruption in determining performance on naming tasks among individuals with aphasia. However, scholarly pursuit of a neurological explanation has overlooked the fundamental cornerstone of individual health—the underlying social, economic, and environmental factors that shape how they live, work, and age, also known as the social determinants of health (SDOH). This study examines the correlation between naming performance and these underlying factors.

Methods

Individual level data from the 2010 Moss Aphasia Psycholinguistic Project Database (MAPPD) was matched with the 2009–2011 Medical Expenditure Panel Survey (MEPS) using a propensity score algorithm based on functional, health, and demographic characteristics. Multilevel, generalized, nonlinear regression models were applied to the resulting data set to assess the correlation between the Boston Naming Test (BNT) percentile score and age, income, sex, race, household size, marital status, aphasia type, and region of residence. Poisson regression models with bootstrapped standard errors were used to estimate these relationships

Results

Discrete dependent variable estimation with non-normal prior specification included individual level (age, marital status, years of education), socioeconomic (family income), health (aphasia type), household (family size), and environmental (region of residence) characteristics. Regression results indicated that, relative to individuals with Wernicke's, individuals with Anomic (0.74, SE = 0.0008) and Conduction (0.42, SE = 0.0009) aphasia performed better on the BNT. While age at the time of testing was not significantly correlated, higher income level (0.15, SE = 0.0003) and larger family size (0.002, SE = 0.002) was associated with higher BNT score percentiles. Finally, Black persons with aphasia (PWA) (-0.0124, SE = 0.0007) had lower average score percentiles when other factors were held constant.

Conclusions

The findings reported here suggest higher income and larger family size are associated with better outcomes. As expected, aphasia type was significantly associated with naming outcomes. However, poorer performance by Black PWA and individuals with low income suggests that SDOH can play a critical role (positive and negative) in naming impairment in some populations with aphasia.