SAT0242 REGIONAL VARIATION IN CARDIOVASCULAR DISEASE AMONG SLE PATIENTS
Authors: Y. Zheng, H. Xie, L. LI, J. Esdaile, A. Aviña
Journal: Annals of the Rheumatic Diseases (2020)

Objectives: To evaluate whether the risk of cardiovascular disease (CVD) including myocardial infarction (MI) and cerebrovascular (CVA) differs across geographic regions among SLE patients. Methods: We identified SLE patients using two ICD codes 60 days apart within two years recorded in Medical Services Plan (MSP) or hospital discharge database (DAD). We defined the second of two diagnosis dates as the index date. We included incident SLE patients (7-year continuous registries in MSP before the first diagnosis date) with an index date between 1997 and 2012 and excluded patients with previous MI or CVA before the index date. We followed each patient from the index date up to 10 years and censored at the date of death date, leaving the province, or March 31, 2015. We assessed the incident CVD that was defined as the first ever diagnosis of MI or CVA recorded in DAD or as the primary cause of death in Vital Statistics. We also evaluated MI and CVA separately. The Province’s publicly administered and funded health care system is organized into five regional health authorities (HA): Interior (IHA), Fraser (FHA), Vancouver Coastal (VCHA), Vancouver Island (VIHA), and Northern (NHA) [Figure 1(a)].We assigned each patient the HA she/he was registered at the index date. We extracted baseline covariates using the information during a period of 365 days prior to the index date, including socio-demographic characteristics, health care resource use, comorbidities, and prescription medication use. We calculated the incident rate (IR) of MI, CVA, and CVD (first ever MI or CVA) by HA. Using Cox Proportional Hazard model adjusting for potential confounders at baseline, we estimated the adjusted hazard ratios (aHR) of CVD for each HA compared to FHA or VCHA which have the large proportion of provincial population and SLE patients. We evaluated the regional disparities in MI and CVA separately using the same methods. Figure 1. HA and CVD Incident Rate Results: We included 3,960 incident SLE patients free of CVD at baseline with a mean (SD) age of 48.5 (15.8), including 726 (18.3%) from IHA, 1634 (42.3%) from FHA, 854 (21.6%) from VCHA, 504 (12.7%) from VIHA, and 242 (6.1%) from NHA. During 26378 person-year (PY) follow-up, 133 patients developed incident CVD including 91 MI and 43 CVA. [Table 1] Table 1. Incident Rates and HR HA Incidence aHR (95%CI ) N PY IR (95%CI ) 10,000 PY Reference: FHA Reference: VCHA CVD IHA 35 4579 76(54,105) 1.93(1.17,3.2 ) 2.05(1.17,3.58 ) FHA 39 11197 35(25,47) ref 1.06(0.64,1.76) VCHA 27 5844 46(31,66) 0.94(0.57,1.57) ref VIHA 22 3165 70(44,103) 1.65(0.96,2.83) 1.74(0.98,3.11) NHA 10 1592 63(31,110) 1.81(0.86,3.8) 1.92(0.88,4.17) MI IHA 24 4579 52(34,76) 2.09(1.14,3.83 ) 1.81(0.95,3.47) FHA 27 11197 24(16,34) ref 0.87(0.48,1.56) VCHA 21 5844 36(23,54) 1.15(0.64,2.07) ref VIHA 12 3165 38(20,64) 1.29(0.64,2.58) 1.12(0.54,2.31) NHA 7 1592 44(19,85) 2.11(0.88,5.11) 1.84(0.74,4.56) CVA IHA 11 4579 24(12,41) 1.79(0.71,4.55) 2.35(0.8,6.88) FHA 12 11197 11(6,18) ref 1.31(0.49,3.48) VCHA 7 5844 12(5,23) 0.76(0.29,2.03) ref VIHA 10 3165 32(16,55) 2.79(1.14,6.85 ) 3.66(1.34,10.01 ) NHA &lt;5 1592 19(5,49) 1.45(0.36,5.72) 1.89(0.44,8.22) The IR of CVD varied from 35 in FHA to 76 per 10,000 PY in IHA [Figure 1(b)]. IHA had significantly higher risk of CVD than FHA (aHR=1.93, 95%CI=1.17~3.2) and VCHA (aHR=2.05, 95%CI=1.17~3.58). The IR of MI varied from 24 in FHA to 52 per 10,000 PY in IHA [Figure 2(a)]. IHA had significantly higher risk of MI than FHA (aHR=2.09, 95%CI=1.14~3.83). Figure 2. MI and CVA incident Rate by HA The IR of CVA varied from 11 in FHA to 32 per 10,000 PY in VIHA [Figure 2(b)]. VIHA had significantly higher risk of CVA than FHA (aHR=2.79, 95%CI=1.14~6.85) and VCHA (aHR=3.66, 95%CI=1.34~10.01). Conclusion: Compared with FHA and VCHA, IHA had higher risk of CVD and VIHA had higher risk of CVA. IHA also had higher risk of MI than FHA. Disclosure of Interests: None declared