Modifying and Validating a Measure of Chronic Stress for People With Aphasia

Chronic stress is likely a common experience among people with the language impairment of aphasia. Importantly, chronic stress reportedly alters the neural networks central to learning and memory-essential ingredients of aphasia rehabilitation. Before we can explore the influence of chronic stress on rehabilitation outcomes, we must be able to measure chronic stress in this population. The purpose of this study was to (a) modify a widely used measure of chronic stress (Perceived Stress Scale [PSS]; Cohen & Janicki-Deverts, 2012) to fit the communication needs of people with aphasia (PWA) and (b) validate the modified PSS (mPSS) with PWA.

Following systematic modification of the PSS (with permission), 72 PWA completed the validation portion of the study. Each participant completed the mPSS, measures of depression, anxiety, and resilience, and provided a sample of the stress hormone cortisol extracted from the hair. Pearson's product-moment correlations were used to examine associations between mPSS scores and these measures. Approximately 30% of participants completed the mPSS 1 week later to establish test-retest reliability, analyzed using an interclass correlation coefficient.

Significant positive correlations were evident between the reports of chronic stress and depression and anxiety. In addition, a significant inverse correlation was found between reports of chronic stress and resilience. The mPSS also showed evidence of test-retest reliability. No association was found between mPSS score and cortisol level.

Although questions remain about the biological correlates of chronic stress in people with poststroke aphasia, significant associations between chronic stress and several psychosocial variables provide evidence of validity of this emerging measure of chronic stress.