Survival over 5 years in the initial hospital survivors with acute coronary syndrome: a comparison between a community hospital and a tertiary hospital in New Zealand.
OBJECTIVE
To compare the outcome of hospital survivors with acute coronary syndrome (ACS) discharged from a community hospital (Invercargill hospital) versus from a tertiary teaching (Dunedin) hospital followed for up to 5 years.


METHODS
All ACS survivors discharged from Dunedin and Invercargill coronary care units between the years 2000-2002 were included. We previously found higher 1-year mortality for Invercargill patients but the explanation was unclear.


RESULTS
Of the 844 patients admitted to Dunedin and 299 admitted to Invercargill hospital, 1057 survived the index ACS episode and formed the cohort for the current study. At 2 years, the mortality of these initial survivors was 8.5% higher for Invercargill patients (18.4% vs 9.9%, p<0.001). Over up to 5 years of follow-up, comparing Invercargill patients to Dunedin patients, the unadjusted hazard ratio for mortality was 1.26 (95%CI: 0.90-1.75). After adjusting to the hospital discharge GRACE score (119+/-40 for Dunedin patients and 130+/-40 for Invercargill patients, p=0.001), this dropped to 1.12 (95%CI: 0.80-1.57). After further adjusting to the discharge medications aspirin (97% vs 98%) and ACE-inhibitors (53% vs 49%), this was 1.14 (95%CI 0.81-1.59). After further adjusting to the use of beta-blockers (78% vs 71%), this was 1.07 (95%CI: 0.76-1.50). After final adjustment for the use of statins (65% vs 42%), this was 0.96 (95%CI: 0.68-1.36).


CONCLUSIONS
Patients discharged from Invercargill hospital fare worse over the first 2-years and tended to fare worse over the first 5-years. This was due both to their higher baseline risk at discharge and the under-use of statins. Of note, PHARMAC rules for statins only changed around the end of the study period allowing more liberal use of statins.
Wong
Cheuk-Kit
CK
Department of Cardiology, Dunedin School of Medicine, University of Otago, Dunedin Public Hospital, Dunedin. cheuk-kit.wong@healthotago.co.nz
Tang
Eng Wei
EW
Herbison
Peter
P
D000208:Acute Disease; D000368:Aged; D000789:Angina, Unstable / Q000628:therapy; D015906:Angioplasty, Balloon, Coronary / Q000706:statistics & numerical data; D002300:Cardiac Care Facilities / Q000706:statistics & numerical data*; D001026:Coronary Artery Bypass / Q000706:statistics & numerical data; D003327:Coronary Disease / Q000401:mortality* / Q000628:therapy*; D019317:Evidence-Based Medicine / Q000706:statistics & numerical data; D005260:Female; D017052:Hospital Mortality; D006764:Hospitals, Community / Q000706:statistics & numerical data*; D006769:Hospitals, General / Q000706:statistics & numerical data*; D006784:Hospitals, Teaching / Q000706:statistics & numerical data*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000145:classification / Q000628:therapy; D009520:New Zealand / Q000453:epidemiology; D010043:Outcome and Process Assessment, Health Care; D012042:Registries; D012189:Retrospective Studies; D012307:Risk Factors; D016019:Survival Analysis; D017741:Survivors; D013577:Syndrome; D015912:Thrombolytic Therapy / Q000706:statistics & numerical data