Cardiovascular Risk At Incidence Of Giant Cell Arteritis: A Population Based Retrospective Cohort Study
- Udayakumar, P. Deepak MD
- Chandran, Arun K. MBBS; Crowson, Cynthia S. MS; Warrington, Kenneth J. MD; Matteson, Eric L. MD, MPH
- Monday, October 28, 2013
- Presenter Available:
- 9:00 am - 11:00 am
- Poster Available:
- 8:30 am - 4:00 pm
- Exhibit Hall B2-C-D
- Session Title:
- Vasculitis II
- Abstract Category:
Background/Purpose: Many systemic inflammatory rheumatic conditions are associated with increased cardiovascular (CV) risk. We aimed at assessing the CV risk at incidence of giant cell arteritis (GCA).
Methods: We retrospectively reviewed a population-based incidence cohort of GCA patients diagnosed between 1950 and 2009 based on American College of Rheumatology 1990 GCA classification criteria. We also included patients ≥ 50 years of age with elevation of erythrocyte sedimentation rate or C-reactive protein and computed tomography, magnetic resonance imaging or positron emission tomography evidence of large vessel vasculitis involving ascending aorta and its branches. We compared this cohort with age, sex and calendar year matched cohort from the same population. All subjects were longitudinally followed through all available community medical records until death, migration or April 30, 2013. Data was collected on all documented episodes of acute coronary syndrome (ACS) events prior to GCA incidence/index date and CV risk factors at GCA incidence/index date. Chi-square tests were used to compare characteristics between GCA and non-GCA cohort.
Results: We identified 245 patients in GCA cohort and 245 age, sex and calendar year matched patients in non-GCA cohort. At GCA incidence, 107 (44%) GCA subjects were on antihypertensives as opposed to 127 (52%) non-GCA subjects (p=0.08). Mean high density lipoprotein (HDL) was higher in GCA cohort [61.5 mg/dl; standard deviation (SD) 17.1] than non-GCA cohort (55.3 mg/dl; SD 17.9) (p=0.034). Mean triglycerides was lower in GCA cohort (124.2 mg/dl; SD 59.6) than non-GCA cohort (148.8 mg/dl; SD 77.5) (p=0.029). Mean low density lipoprotein (LDL) and total cholesterol were not different between the two cohorts. 23 (9.6%) subjects were on lipid lowering medication in GCA cohort as opposed to 39 (16.1%) in non-GCA cohort (p=0.032). No difference was noted in smoking status, obesity or chronic kidney disease between the two cohorts. Diabetes mellitus was present in 17 (6.9%) GCA subjects and 40 (16.3%) non-GCA subjects (p=0.001). Mean overall Framingham 10 year cardiovascular risk score was 30% (SD 19) in GCA subjects and 34% (SD 23) in non-GCA subjects (p=0.096) at incidence/index date. Positive family history of premature ACS was less frequent in GCA (2 of 26 subjects; 13%) than non-GCA cohort (10 of 32 subjects; 48%) (p=0.024). Occurrence of acute coronary syndrome (ACS) prior to GCA incidence/index date was similar between the two cohorts: 18 episodes (7.4%) in GCA cohort versus 17 episodes (6.9%) in non-GCA cohort (p=0.86).
Conclusion: Multiple cardiovascular risk factors are more favorable at incidence of GCA when compared to non-GCA subjects of similar age and gender. Anti-hypertensives and lipid lowering medications are less frequently used in GCA subjects at incidence. Framingham 10 year cardiovascular risk may be lesser at GCA incidence although this did not achieve statistical significance in our study. As GCA is a disease that almost exclusively affects the elderly, there may be a component of healthy cohort bias causing this effect.
- P. D. Udayakumar, None; A. K. Chandran, None; C. S. Crowson, None; K. J. Warrington, None; E. L. Matteson, None.