Reduction in total recurrent cardiovascular events in acute coronary syndrome patients with low-density lipoprotein cholesterol goal <70 mg/dL: a real-life cohort in a developing country

Surarong Chinwong; Jayanton Patumanond; Dujrudee Chinwong; John Joseph Hall; Arintaya Phrommintikul

doi:10.2147/TCRM.S96016

Reduction in total recurrent cardiovascular events in acute coronary syndrome patients with low-density lipoprotein cholesterol goal <70 mg/dL: a real-life cohort in a developing country

Ther Clin Risk Manag. 2016 Mar 3:12:353-60. doi: 10.2147/TCRM.S96016. eCollection 2016.

Authors

Surarong Chinwong¹, Jayanton Patumanond², Dujrudee Chinwong¹, John Joseph Hall³, Arintaya Phrommintikul⁴

Affiliations

¹ Department of Pharmaceutical Care, Faculty of Pharmacy, Chiang Mai University, Chiang Mai, Thailand.
² Center of Excellence in Applied Epidemiology, Faculty of Medicine, Thammasat University, Pathum Thani, Thailand.
³ Centre for Clinical Epidemiology and Biostatistics, School of Medicine and Public Health, Faculty of Health, University of Newcastle, Callaghan, NSW, Australia.
⁴ Department of Internal Medicine, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand.

Abstract

Background: For investigations into cardiovascular disease, the first problematic event (ie, nonfatal acute coronary syndrome (ACS), nonfatal stroke, or all-cause mortality) generally was considered as the primary end point; however, ACS patients often experience subsequent events, which are rarely considered. This study reports an investigation into whether achieving a low-density lipoprotein cholesterol (LDL-C) goal of <70 mg/dL (1.8 mmol/L) is associated with a reduction in total recurrent cardiovascular events in a cohort of ACS patients hospitalized in northern Thailand.

Methods: The medical charts and the electronic hospital database of ACS patients treated with statins at a tertiary hospital in Thailand between 2009 and 2012 were reviewed. Patients were checked for their LDL-C goal attainment, and then were followed for subsequent events until the last follow-up date, or to December 31, 2012. The Wei-Lin-Weissfeld method was used for multiple time-to-events data to investigate the association between achieving an LDL-C goal of <70 mg/dL and total recurrent cardiovascular events.

Results: Of 405 eligible patients, 110 patients attained an LDL-C goal of <70 mg/dL. During a median follow-up of 1.94 years, the majority of patients (88.6%) had no subsequent cardiovascular events, while 46 patients experienced at least one recurrent cardiovascular event: 36 with one event, six with two events, two with three events, one with four events, and one with seven events. Compared to patients with an LDL-C ≥100 mg/dL, patients achieving an LDL-C of <70 mg/dL were significantly less likely to experience total cardiovascular events (adjusted hazard ratio =0.29; 95% confidence interval =0.09-0.87; P-value =0.028); the result was similar to patients with an LDL-C of 70-100 mg/dL, but it was not significant (adjusted hazard ratio =0.53; 95% confidence interval =0.23-1.26; P-value =0.154).

Conclusion: ACS patients receiving statins who attained an LDL-C <70 mg/dL experienced a reduction in total recurrent cardiovascular events compared to those with LDL-C ≥100 mg/dL.

Keywords: LDL-C goal; WLW method; multiple events; multiple time-to-events; recurrent events; statins; subsequent events.