The association between diabetes and hypertension time course, their cumulative co-exposure, and post-coronary artery bypass graft outcomes.

Abstract

Background: The association between patient outcomes and cumulative effects of cardiovascular risk factors over time is recognized but poorly quantified. This study quantitively addressed the impact of diabetes and hypertension duration, and their combined effect, on post-coronary artery bypass grafting (CABG) outcomes.

Methods: This single-center cohort study included patients who underwent coronary angiography followed by isolated CABG (n=10803, median follow-up: 111.3 months) from 2007 to 2017. Study outcomes comprised all-cause mortality and major adverse cardiocerebrovascular events (MACCE). Cox regressions were used to assess the association between risk factors' duration (<5 years, 5-10 years, ≥10 years) and study outcomes among the total cohort and stratified by the co-presence of risk factors.

Results: The study population aged 65.56 ± 10.00 years (75.3% male, 40.1% diabetes, 64.1% hypertension). The risk of study outcomes increased with increasing duration of diabetes (adjusted-hazard ratio from "0-5y" to "≥10y" group for all-cause mortality: 1.37[95%CI: 1.23-1.52] to 1.91[1.69-2.16], and for MACCE: 1.23[1.14-1.34] to 1.59[1.44-1.76]). When stratified by hypertension status, the association between shorter diabetes duration and study outcomes became non-significant among non-hypertensive patients, while the association persisted for their hypertensive counterparts (reference group: non-diabetic patients). An increasing risk pattern was observed with longer hypertension duration (from 1.38[1.25-1.53] to 1.51[1.30-1.75] for all-cause mortality and 1.27[1.18-1.37] to 1.39[1.24-1.55] for MACCE). This risk enhancement was more pronounced when diabetes co-existed.

Conclusion: Our results highlight the significance of risk factor exposure duration in patient risk assessment. These insights could be valuable for enhancing existing risk assessment tools and developing tailored preventive strategies.