Early maladaptive cognitive schema as predictors of acute phase post-stroke depression

Post-stroke depression is a leading cause of disability and the identification of risk factors is critical for rehabilitation and prevention initiatives. Early Maladaptive Cognitive Schema (EMS) have been implicated with depression with no known medical cause but not previously explored in post-stroke depression. The overall purpose of the study was to explore the role of EMS in post stroke depression. The Young Schema Questionnaire-Short Form (YSQ-SF) is used to assess EMS, and one objective was the validation of the YSQ-SF in a post-stroke sample. The validated questionnaire was subsequently used to identify EMS as covariates of post-stroke acute phase depression. Further, additional variables of health locus of control, social support and level of disability, among others, were also explored as covariates. The sample consisted of a total of 69 participants (M=64.97, SD=14.72 years old) who were recruited on average 25.10 days (SD=29.61) post-stroke. The theoretical structure of the YSQ-SF was successfully replicated in this post-stroke sample with 68 of the original 75 items having loadings greater than 0.40 and internal consistencies ranging between 0.62 and 0.89, and significant acute phase covariates with acute phase depression were the Failure to Achieve and the Vulnerability to Harm EMS. These findings show promising trends in the involvement of EMS in post-stroke psychopathology which warrants further investigation in this clinical group. (217 words)

Summary

Stroke is the third most common cause of disability worldwide (Mackay et al., 2004) and post-stroke depression is the most frequent neuropsychiatric disorder affecting acute stroke patients (Caeiro et al., 2006). Post-stroke depression is commonly diagnosed during the acute and subacute phase post-stroke with peak prevalence 3-6 months post-stroke (Newberg et al., 2006) and is associated with higher rates of morbidity, mortality and poor rehabilitation outcomes (Newberg et al., 2006; Whyte et al., 2006).
Psychosocial factors associated with post-stroke depression include an external health locus of control (Thomas et al., 2006; Johnston et al., 1999), and lack of a social network and tangible support (Glymour et al., 2008; Huang et al., 2010; Salter et al., 2010). Demographic variables include gender and race, with women being at increased risk of depression post-stroke (Paolucci et al., 2005; Zhang et al., 2013) as well as white, non-Hispanic patients (Jia et al., 2010). Further, some medical/illness factors including lesion location (Allman, 1991; Caeiro et al., 2006), aphasia (Thomas et al., 2006), and level of impairment on activities of daily living (Hilari et al., 2010) increase risk for depression. Schemas are mental structures that are created through experience and guide our response to our environment (Tuddenham, 1966; Berlyne, 1957). Young, Klosko & Weishaar (2003) presented 15 Early Maladaptive Cognitive Schema (EMS), which fit into 5 higher order domains, and are said to be the core of psychopathology and the result of adverse childhood experience. The Young Schema Questionnaire Short Form (YSQ-SF) is a 75-item questionnaire used to assess EMS. The psychometric properties of the YSQ-SF have been assessed in undergraduate and various clinical samples and translated into multiple languages (Wellburn et al., 2000; Lachenal-Chevallet et al., 2006; Cui et al., 2011; Calvete et al., 2005). The YSQ-SF appears sound for research and clinical practice, however the psychometric properties have not previously been assessed in a post-stroke clinical sample. The main objectives of this research were to assess the factor structure of the YSQ-SF in a post-stroke population, and to incorporate EMS as potential risk factors in the acute phase post-stroke.
Sixty-nine post-stroke patients with an average age of 64.97 years (SD=14.72) were recruited 25.10 days (SD= 29.61) post stroke. The BDI, YSQ-SF, Social Support Questionnaire, Barthel Index, and Multidimensional Health Locus of Control were administered and demographic variables of gender, location of stroke, marital status, ethnicity, living arrangements, level of education, occupation, and previous history of psychopathology were collected. Cross-sectional analyses included a factor analysis for the validation of the YSQ-SF, and a regression identifying covariates of depression. Due to the sample size and recommendations for a factor analysis, the factor structure was assessed using the higher order domain breakdown creating an acceptable item to participant ratio for each domain. Domain 1: Disconnection/Rejection 2.76:1, Domain 2: Impaired Autonomy 3.45:1, Domain 3: Impaired Limits 6.9:1, Domain 4: Other-Directedness 6.9:1, and Domain 5 Overvigilance 6.9:1. The results of the current study yielded a successful replication of the YSQ-SF, validating all 15 EMS with 68 out of the original 75 items. Factor loadings were greater than 0.40, and internal consistencies ranged between 0.62 and 0.89, with 10 of the 15 schema over the accepted 0.70 level. Overall, the factor structure and underlying construct of each EMS was not compromised in this sample and despite sample size limitations the current results are consistent with previous research of Welburn et al. (2002), Lachenal-Chevallet et al. (2006), and Cui et al. (2011) who replicated the theoretical structure with a range between 59 and 70 of the 75 items and between 13 and 15 of the original 15 schemas. Of all the variables collected only the EMS of Failure to Achieve and Vulnerability to Harm were significant in the regression model. As both variables increased, depression scores increased. The EMS of Failure to Achieve has been positively correlated with depression in previous studies and in Wegener et al. (2003) the greater the decrease in the Failure to Achieve EMS was associated with greater symptom reduction in patients with major depressive disorder. Overall, EMS have not previously been explored in a post-stroke population and the results show promising trends in the influence and involvement of EMS in post-stroke psychopathology. EMS warrant further investigation in this clinical group that is highly vulnerable to such influences mainly for rehabilitation and prevention purposes, such as the use of the YSQ-SF as a screening instrument and the use of Schema Therapy as a new potential treatment modality for post-stroke depression.