Patient factors and health outcomes associated with illness perceptions in people with gout

Daniel Selvadurai; Matthew J Coleshill; Richard O Day; Nancy E Briggs; Marcel Schulz; Jennifer Reath; Eindra Aung

doi:10.1093/rheumatology/kead501

Patient factors and health outcomes associated with illness perceptions in people with gout

Rheumatology (Oxford). 2023 Sep 28:kead501. doi: 10.1093/rheumatology/kead501. Online ahead of print.

Authors

Daniel Selvadurai^{1

2}, Matthew J Coleshill^{3

4}, Richard O Day^{1

2}, Nancy E Briggs⁵, Marcel Schulz^{1

2}, Jennifer Reath⁶, Eindra Aung^{1

2

7}

Affiliations

¹ St Vincent's Healthcare Clinical Campus, UNSW Medicine & Health, UNSW Sydney, Sydney, Australia.
² Department of Clinical Pharmacology & Toxicology, St Vincent's Hospital, Sydney, Australia.
³ Black Dog Institute, Sydney, Australia.
⁴ UNSW Medicine & Health, UNSW Sydney, Sydney, Australia.
⁵ Stats Central, Mark Wainwright Analytical Centre, UNSW Sydney, Sydney, Australia.
⁶ Department of General Practice, Western Sydney University, Sydney, Australia.
⁷ Kolling Institute of Medical Research, Pain Management Research Institute, University of Sydney, Sydney, Australia.

PMID: 37769230
DOI: 10.1093/rheumatology/kead501

Abstract

Objective: Illness perceptions are views and beliefs formed in response to a health threat which may influence self-management behaviours and chronic disease outcomes. Despite effective medication, sub-optimal outcomes in gout are common. This study aimed to quantitatively investigate illness perceptions in gout to examine how illness perceptions relate to health outcomes.

Methods: Data were obtained from a randomised-controlled trial where people with gout (n = 493) completed surveys measuring illness perceptions (Brief Illness Perception Questionnaire (B-IPQ)), gout flares, medication adherence, health-related quality of life, healthcare utilisation and productivity, alongside serum urate blood tests at baseline, 6- and 12-month follow-ups. Multivariable linear regression identified patient factors independently associated with each B-IPQ item score. Logistic and linear regression, adjusted for age and sex, determined whether baseline B-IPQ items could predict current and future health outcomes.

Results: Younger individuals and those with severe gout were more likely to experience pessimistic illness perceptions at baseline. Optimistic illness perceptions were associated with lower odds of having at least one flare in the preceding 6 months. Every 1-point increase in B-IPQ treatment control, indicating the optimistic view that gout is treatable, decreased the odds of a recent flare prior to baseline by 33% (OR : 0.67; 95%CI : 0.53,0.85; p< 0.001) and prior to 12-month follow-up by 15% (OR : 0.85; 95%CI : 0.76,0.96; p= 0.01). Pessimistic illness perceptions also predicted poorer medication adherence, health-related quality of life and productivity but not serum urate levels.

Conclusion: Modifying pessimistic illness perceptions, including, but not limited to, patient education, may promote prudent self-management behaviours and better outcomes in gout.

Trial registration: Australian New Zealand Clinical Trials Registry; https://www.anzctr.org.au/; ACTRN12616000455460.

Keywords: B-IPQ; Gout; illness perceptions; medication adherence; patient-reported outcomes; serum urate.