THU0064 COMPARISON OF MORTALITY IN RHEUMATOID ARTHRITIS AND DIABETES – THE HUNT POPULATION-BASED STUDY
Authors: Ingrid Saether Houge, Mari Hoff, Ranjeny Thomas, Vibeke Videm
Journal: Annals of the Rheumatic Diseases (2019)

<h3>Background</h3> Patients with rheumatoid arthritis (RA) have higher mortality rates than the general population, primarily from cardiovascular disease (CVD). Diabetes is an acknowledged risk factor for early death, mainly due to CVD. The reported risk for CVD is increased for both patients with RA and diabetes, however the effect of diabetes appears to be greater than that of RA (1). <h3>Objectives</h3> To assess whether the increase in all-cause mortality rates in patients with RA and patients with diabetes are similar, compared to the general population. <h3>Methods</h3> Data were obtained from the 2<sup>nd</sup> and 3<sup>rd</sup> survey of the population-based Nord Trøndelag Health Study (HUNT) and the Norwegian National Cause of Death Registry. The RA diagnoses have previously been validated (2). The definition of diabetes was self-reported diabetes, self-reported use of antidiabetica, or non-fasting blood glucose level &gt;11.1 mmol/L. The participants were followed from their participation in HUNT to death or to 31.12.2014, whichever came first. Participants with other types of inflammatory arthritis or missing data for any of the variables in the model were excluded. Furthermore, the patients with both RA and diabetes were not included in the analysis (n=33). Participants with neither RA nor diabetes were defined as controls. RA patients, diabetes patients and controls were compared using Cox proportional hazard regression modelling, with age as the time scale. The model was adjusted for sex, smoking status, previous CVD, body mass index (BMI), hypertension, total cholesterol and creatinine. To obtain proportional hazards, an interaction term with age ≤75 years vs &gt;75 years was included for diabetes, smoking and previous CVD. The effects of the groups were compared using overlap of confidence intervals. <h3>Results</h3> There were 123 (32%) deaths in the RA group, 1280 (44%) deaths in the diabetes groups and 11,641 (18%) deaths in the control group. The hazard ratio (HR) for RA was 1.24 (95% confidence interval: CI 1.02-1.46, p-value 0.013). The HR for diabetes was 1.82 (CI 1.60-2.05, p-value &lt;0.001) for those aged ≤75 years and 1.48 (CI 1.39-1.58, p-value 0.004) for those aged &gt;75 years. RA patients had a significantly lower HR compared to diabetes patients for age ≤75 years, but not for age &gt;75 years. <h3>Conclusion</h3> Patients with RA or diabetes had significantly higher mortality rates than controls, with larger HR for diabetes than for RA. The HR for RA was significantly lower than for diabetes for patients ≤75 years, but not for patients &gt;75 years. This may be due to survival bias in diabetes patients &gt;75 years. <h3>References</h3> 1 Curtis, J. R.&nbsp;et al.,&nbsp;Is Rheumatoid Arthritis a Cardiovascular Risk-Equivalent to Diabetes Mellitus?&nbsp;Arthritis Care Res,&nbsp;2018.&nbsp;70(11):&nbsp;p.1694-1699 2&nbsp;Videm, V,&nbsp;et al., Self-reported Diagnosis of Rheumatoid Arthritis or Ankylosing Spondylitis has Low Accuracy: Data from the Nord-Trondelag Health Study. J Reumatol,&nbsp;2017.&nbsp;44(8):p.1134-1141 <h3>Disclosure of Interests</h3> Ingrid Saether Houge: None declared, Mari Hoff: None declared, Ranjeny Thomas Grant/research support from: Janssen Biotec Inc, Merck and Co, Consultant for: Janssen Biotec Inc, Speakers bureau: Janssen, Merck, Vibeke Videm: None declared