ASSOCIATION BETWEEN POTENTIAL PROGNOSTIC FACTORS AND ADVERSE HEALTH OUTCOMES IN RHEUMATOID ARTHRITIS: A STUDY OF 5658 UK BIOBANK PARTICIPANTS

Background: There is a pressing need to identify simple prognostic factors, which are readily available in primary and secondary care settings, that can predict adverse health outcomes in people with rheumatoid arthritis (RA). Exploring various clinical, physiological and patient-reported measures as prognostic factors may enhance risk stratification and promote more personalised care for RA patients. Objectives: To determine the association, if any, between selected prognostic factors and all-cause mortality and major adverse cardiovascular events (MACE; including myocardial infarction and stroke) in an RA population. Methods: UK Biobank participants that self-reported RA were included in this study. Prognostic factors were selected from the literature based on relevance, predictive potential, simplicity and accessibility in a primary/secondary care setting. Those included were categorised into the following domains: anthropometric measures (body mass index (BMI), body fat percentage, waist circumference, waist-to-hip ratio), functional measures (hand grip strength (HGS), usual walking pace (UWP)), inflammatory markers (C-reactive protein (CRP)), patient-reported measures (pain), physiological measures (blood pressure (BP), heart rate (HR)) and serological markers (rheumatoid factor (RF)), with normal ranges used as reference categories. Associations between individual factors and outcomes were explored using Cox proportional hazards models. Models were adjusted for age, sex, socioeconomic status, number of additional long-term conditions and smoking status in the first instance to identify potential individual predictors. Models were then further adjusted for any identified individual predictors to determine the most important prognostic factors. Results: 5658 (1.1%) UK Biobank participants self-reported RA (mean age 59 (standard deviation 7.13); 69.8% female). 670 deaths (median 11 years) and 370 MACE (median 8 years) were recorded during the follow-up period. Several significant individual associations with all-cause mortality ( Figure 1A ) and MACE ( Figure 1B ) were found. After further adjustment for these significant individual predictors, the following factors demonstrated significant associations with risk of all-cause mortality, independent of the other significant predictors: underweight BMI (<18.5kg/m ) (hazard ratio (HR) 2.96 [95% confidence intervals (CI) 1.59-5.51]), obese BMI (≥30.0kg/m ) (HR 0.52 [95% CI 0.36-0.76]), 3-10mg/L CRP (HR 1.41 [95% CI 1.14-1.75]), >10mg/L CRP (HR 1.77 [95% CI 1.39-2.26]), low HGS (<16kg female or <27kg male) (HR 1.28 [95% CI 1.05-1.56]) and slow UWP (patient-reported) (HR 1.31 [95% CI 1.06-1.62]). Likewise, the following factors were found to be significantly associated with MACE, independent of other significant factors: >10mg/L CRP (HR 1.62 [95% CI 1.19-2.20]), low HGS (HR 1.61 [95% CI 1.26-2.07]) and slow UWP (HR 1.50 [95 % CI 1.15-1.97]). Conclusion: In this RA population, the risk of all-cause mortality was approximately three-fold higher in those who have an underweight BMI when compared to those who have a BMI in the normal range, when adjusted for all other significant factors, while an obese BMI appeared to lower this risk, consistent with the “obesity paradox” reported in RA [1]. Increased levels of CRP, low HGS and slow UWP were also all independently associated with an increased risk of all-cause mortality and MACE. Our findings highlight the potential value of these factors for predicting adverse outcomes in RA populations. A simple, yet multidimensional approach to risk assessment, combining well-tolerated, easily repeatable measures such as those included here may provide important prognostic information at both primary and secondary care levels, while limiting excessive and overly invasive testing on RA patients. REFERENCES: [1]Wolfe F, Michaud K. Effect of body mass index on mortality and clinical status in rheumatoid arthritis. Arthritis Care Res (Hoboken ). 2012; 64(10): 1471-1479. doi:10.1002/acr.21627 Acknowledgements: This work is supported by the Medical Research Council [grant number: MR/N013166/1]. Disclosure of Interests: Jordan Canning: None declared, Stefan Siebert Grant/research support from: Departmental research grants/support from: AbbVie, Amgen, Boehringer Ingelheim, Bristol Myers Squibb, GSK, Janssen, Novartis and UCB., Bhautesh Jani: None declared, Frances Mair: None declared, Barbara Nicholl: None declared. Citation: , volume 81, supplement 1, year 2022, page 554Session: Rheumatoid arthritis - prognosis, predictors and outcome (POSTERS only)