POS0876 PREVALENCE OF 39 COMORBIDITIES ACROSS RHEUMATOID ARTHRITIS, PSORIATIC ARTHRITIS, AND ANKYLOSING SPONDYLITIS
Authors: J. Southworth, K. Rogers, S. S. Zhao
Journal: Annals of the Rheumatic Diseases (2024)

<h3>Background:</h3> Comorbidities are common among people with inflammatory arthritis (IA) and are associated with greater disease activity and functional impairment. They can also influence management decisions and treatment outcomes; therefore, characterising comorbidities has direct clinical relevance. Studies have typically described comorbidities separately for each IA, whereas comparisons across IAs are limited. <h3>Objectives:</h3> To compare the prevalence of 39 chronic conditions across rheumatoid arthritis (RA), psoriatic arthritis (PsA), ankylosing spondylitis (AS) and controls without IA. <h3>Methods:</h3> We utilised UK Biobank data from half a million individuals aged 40-69 recruited between 2006-2010. The analysis focused on a subset with linked primary care data. Definitions for RA, PsA, and AS utilised at least one of ICD-10, Read (primary care) codes, or self-reported diagnosis. Comorbidities were selected following the measurement of multiple chronic diseases by the Scottish National Health Service and were identified using at least one ICD-10 and/or Read codes. Descriptive statistics were performed using ANOVA for continuous and Chi-squared tests for categorical variables. Logistic regression models assessed the odds of each comorbidity in RA, PsA, and AS compared to non-IA controls, adjusting for age, sex, BMI (kg/m<sup>2</sup>) (except for obesity analysis), CRP (mg/dL), and smoking status (current, previous, never). <h3>Results:</h3> A total of 230,055 UK biobank participants were included: 102,882 (45.4%) were male, 127173 (54.6%) were female, and the mean age was 56.5 (SD 8.1) years. 1969 (0.9%) had RA, 606 (0.3%) had PsA, 797 (0.4%) had AS, and 226,683 (98.5%) non-IA control. The mean age was 59.6 (SD 6.9) for RA, 56.9 (SD 7.3) for PsA, 57.8 (SD 7.5) for AS and 56.5 (SD 8.1) for controls. The mean BMI for RA, PsA, AS and non-IA were 28.4 (SD 5.6), 28.6 (SD 5.3), 27.7 (SD 4.8) and 27.5 (SD 4.8) respectively. Groups with IA had elevated CRP: 6.2 (SD 9.1) for RA, 4.8 (SD 7.7) PsA, 5.1 (SD 7.6) AS, and 2.6 (SD 4.3) controls. Gender distribution differed with RA being predominantly female (70.6% female) and AS being male-dominant (64.5% male). Amongst the comorbidities, 26 of the 39 (66.7%) showed a statistically significant difference across the four groups (Table 1). Notably, hypertension prevalence was higher in IA participants (9.0%-11.1%) than in controls (5.8%). Similarly, diabetes was more prevalent in IA participants (2.1%-3.3%) compared to controls (1.5%). When comparing comorbidities in adjusted models (Table 2), hypertension was more common across IAs: OR 1.29 (95%CI 1.10-1.53) for RA, OR 1.76 (1.34-2.31) PsA, OR 1.38 (1.07-1.78) AS, compared to controls. Similarly, the odds of dyspepsia were higher than controls: OR 2.06 (95%CI 1.73-2.45) for RA, OR 1.47 (1.01-2.11) for PsA and OR 1.57 (1.16-2.13) for AS. Osteoporosis was more common in RA and AS than in controls: RA OR 3.98 (95%CI 3.08-5.14) and AS OR 4.51 (2.79-7.28). Heart failure odds were also higher in RA and AS: OR 1.90 (95%CI 1.22-2.97) for RA and OR 2.37 (1.29-4.34) for AS. PsA and AS showed higher odds of IBS: PsA OR 1.72 (95%CI 1.15-2.57) and AS OR 1.57 (1.07-2.29). Uniquely in AS participants AF and CKD were more common than controls: AF OR 1.59 (95%CI 1.03-2.45) and CKD OR 3.29 (1.62-6.70). <h3>Conclusion:</h3> In this healthy UK Biobank population, comorbidities were more common in those with inflammatory arthritis, particularly hypertension and dyspepsia. These findings emphasise the need for holistic care including optimisation of coexisting conditions. <b>Table 1.</b> Prevalence of comorbidities across inflammatory arthritis and controls. <b>Table 2.</b> Odds of each comorbidity compared to controls in adjusted logistic models. N/A arises where comorbidity prevalence is zero. Models were adjusted for age, sex, BMI (except for obesity), CRP and smoking status. Bolded results are statistically significant. <h3>Acknowledgements:</h3> <b>NIL.</b> <h3>Disclosure of Interests:</h3> Joshua Southworth: None declared, Kira Rogers: None declared, Sizheng Steven Zhao UCB, Novartis, UCB