Comparison of illness representations dimensions and illness representation clusters in predicting outcomes in the first year following diagnosis of type 2 diabetes: Results from the DESMOND trial

Abstract

This article explores the utility of cluster analysis of illness representations, in comparison to analysing each dimension of the individual's illness representation, to predict an individual's response to diagnosis of type 2 diabetes. Participants in a large multi-centre randomised controlled trial of a self-management education intervention for people with type 2 diabetes, completed measures of illness beliefs (coherence, timeline, impact, seriousness, personal responsibility) and depression along with HbA1c and body mass index (BMI), at baseline 4, 8 and 12 months. The results of the cluster analysis were compared with an independent qualitative study of participants' responses to diagnosis and participation in the study. The quantitative analysis of 564 participants for whom complete data were available, identified four clusters of illness representations as the most parsimonious description of the data. The mean profiles of these clusters were comparable with groups identified by the independent qualitative analysis, and predicted the trajectory of illness outcomes over the 1-year follow-up. Combining illness beliefs into discrete clusters may be more useful in understanding patterns of responding to illness than using analysis of illness beliefs dimensions independently.

Illness perception clusters and relationship quality are associated with diabetes distress in adults with Type 2 diabetes

“…More specifically illness perceptions relating to diabetes consequences are associated with poorer emotional wellbeing (Hudson, Bundy, Coventry & Dickens 2014), and personal control mediates the relationship between diabetes distress and HbA1c (Gonzalez, Shreck, Psaros & Safren 2015). Clustering individuals with Type 2 diabetes according to shared illness perception schemas is also shown to provide a useful predictor of depression overtime (Skinner et al 2011); however it is not yet known whether shared illness perception schemas predict diabetes distress.…”

Heterogeneity of change in state affect following insulin therapy initiation in type 2 diabetic patients

“…In developed countries the peak incidence for type 2 diabetes is noted in adults aged about 65 years (Wild, Roglic, Green, Sicree, & King, 2004). Thus, patients significantly younger may perceive the disease as more burdensome and stigmatizing (Skinner et al, 2011), and insulin therapy as interfering with their occupational career (Reach et al, 2013) or social life, which would contribute to increasing NA. As compared to the "no response" subgroup, patients from the ambivalent subgroup representing "challenge response" rated their material status lower and more often had vocational education.…”

“…Moreover, both valences were assumed to be mutually independent, thus separate analyses of change were conducted for negative and positive affect and then their interrelationships were assessed. Finally, since the existing research suggests that sociodemographic variables can differentiate both the affective functioning (Gallo & Matthews, 2003), and potentially also adaptation to illness (Skinner et al, 2011), an attempt was made in our study to examine whether the membership in a specific patient subgroup, defined by trajectories of positive and negative affect changes, would be significantly related to sociodemographic characteristics. Therefore, the following research questions were posed: 1.…”

Self-regulation theory and self-monitoring of blood glucose behavior in type 2 diabetes mellitus.

“…The processes may impact illness representations as well. Skinner and colleagues (2011) found that depression, as measured by a depression screener (HANDS; Zigmond et al, as cited in Skinner et al, 2011) was associated with CSM "cluster" membership. That is, depressed individuals were more likely to belong to a resisters accepting consequences cluster or a resisters cluster of CSM beliefs than more positive CSM clusters.…”

“…Research has supported the IPQ-R as having acceptable to excellent reliability 2011), and it has been used to measure change in illness perceptions in previous diabetes research trials (Davies et al, 2008;Skinner et al, 2011).…”