Illness perceptions in patients with heart failure and an implantable cardioverter defibrillator: Dimensional structure, validity, and correlates of the brief illness perception questionnaire in Dutch, French and German patients

Abstract

Background: Patients' illness perceptions are associated with psychological wellbeing and can be measured with the Brief Illness Perception Questionnaire (B-IPQ). However, little is known about illness perceptions in patients with heart failure. We examined the dimensional structure, validity and clinical and psychological correlates of the B-IPQ in Dutch, French and German patients with heart failure and an implantable cardioverter defibrillator (ICD).

Method: European heart failure patients (n=585) participating in the REMOTE-CIED study completed a set of questionnaires 1-2weeks post ICD-implantation, including the B-IPQ. Information on clinical data was captured from patients' medical records.

Results: A two-factor structure (I='Consequences'; II='Control') represented 7 out of 8 B-IPQ items in the total sample and Dutch, German and French subgroups. The total B-IPQ had a Cronbach's α of 0.69, with the 'Consequences' subscale being more internally consistent (α=0.80). Both the B-IPQ and its 'Consequences' subscale were significantly correlated with a number of psychological characteristics, but not with clinical characteristics. Multivariable logistic regression analysis indicated that threatening illness perceptions as measured with the total B-IPQ were associated with poor health status (OR=2.66, 95%CI=1.72-4.11), anxiety (OR=1.79, 95%CI=1.001-3.19), depression (OR=2.81, 95%CI=1.65-4.77), negative affectivity (OR=1.93, 95%CI=1.21-3.09) and poor ICD acceptance (OR=2.68, 95%CI=1.70-4.22).

Conclusion: The B-IPQ demonstrated good psychometric properties in Dutch, French and German patients with heart failure. Psychological factors were the most important correlates of patients' perceptions of heart failure, emphasizing the importance of targeting maladaptive illness perceptions in this population, due to their impact on patients' wellbeing and quality of life.

Trial registration: ClinicalTrials.gov NCT01691586.

Keywords: Dimensional structure; Heart failure; Illness perceptions; Implantable cardioverter defibrillator; Psychometric properties.