Association between the trajectory of clinical parameters and the risk of cardiovascular disease and mortality in patients diagnosed with diabetes mellitus or hypertension: A systematic review

Abstract

Introduction: Cardiometabolic factors should be monitored regularly for patients with diabetes mellitus (DM)/ hypertension (HT). In addition to the levels of risk factors at a single time point, it is increasingly apparent their changes over time i.e. the trajectory, may be differentially related to the risk of cardiovascular diseases (CVD) and mortality. This study aimed to systematically review evidence on the association between trajectories of risk factor changes and risk of CVD/mortality among patients with DM/HT. Methods: The databases PubMed, MEDLINE, and Embase were searched for articles dated from January 1963 to April 2021. Studies were included if: 1) analyzed trajectories of risk factors including haemoglobin A1c (HbA1c), blood pressure, estimated glomerular filtration rate (eGFR), body mass index (BMI), and blood lipids, 2) performed in the DM/HT population and, 3) included risk of CVD/mortality as outcomes. Results: A total of 22,099 articles were identified. Eleven articles were retained for data collection, where 7, 3, and 1 article investigated the trajectories of HbA1c, systolic blood pressure (SBP), and eGFR respectively, with none on BMI or lipids trajectory. In general, the stable trajectories of risk factors within optimal ranges (HbA1c: 6-7.5%, SBP: 120-140mmHg, eGFR: >60mL/min/1.73m2) over time had the lowest CVD/mortality risk compared to an increasing HbA1c trajectory (from 8% to 10%), an increasing SBP trajectory (from 120-139 to ≥140mmHg), or a decreasing eGFR trajectory (from 90 to 70mL/min/1.73m2). Additionally, a fluctuating HbA1c trajectory (from 8% to 11% then back to 8% over 10 years) was associated with higher CVD risk than the stable one (7-7.5%) after adjustment for mean HbA1c levels over time. Conclusions: A relatively stable and well-controlled trajectory for cardiometabolic risk factors was associated with the lowest risk of CVD/ mortality. More attention should be given to patients with not only suboptimal levels but also with high variability over time.