Beat-to-beat resting blood pressure variability in patients with type 2 diabetes: effect of statin therapy

Abstract

Type 2 diabetes (T2D) is a major health concern affecting more than 30 million people in the United States alone. Approximately two-thirds of patients with T2D develop hypertension, a major risk factor for cardiovascular disease. In addition to higher resting absolute blood pressure (BP), increased variability in BP has also been related to greater cardiovascular disease risk. However, whether patients with T2D display greater beat-to-beat BP variability remains unknown. Herein, we hypothesized that patients with T2D would exhibit greater beat-to-beat BP variability than age and body-weight-matched control subjects. In addition, since previous literature has shown that statins lower cardiovascular disease risk through favorable pleiotropic mechanisms, we further hypothesized that patients with T2D taking statins (T2D+statin) would have a lower beat-to-beat BP variability compared to patients with T2D not taking statins (T2D-statin). Beat-to-beat BP (finger photoplethysmography) and heart rate (ECG) were continuously measured, and absolute BP (automated sphygmomanometer) was measured periodically in patients with T2D (N=23; T2D+statin: N=10, T2D-statin: N=13) and age and body weight-matched control subjects (N=17). Measurements were made over the course of a quiet resting baseline period (9.5±1.3 minutes) with subjects in a supine position. Beat-to-beat BP variability was quantified as standard deviation (SD), range, and average real variability (average change in BP from one heartbeat to the next). Data are presented as mean ± standard deviation. Resting absolute systolic BP, diastolic BP, and mean arterial pressure (MAP) were not different between control subjects and T2D patients (P>0.05 for all). There was also no difference in beat-to-beat systolic BP, diastolic BP, or MAP variability between the groups (e.g., MAP SD: control: 4.5±1.3 mmHg, T2D: 4.7±1.1 mmHg, P=0.763). When comparing T2D patients taking statins and those not taking statins, no difference was observed in absolute resting BP (P>0.05). Likewise, systolic BP variability was not different between groups (SD: T2D-statin: 7.0±2.2 mmHg, T2D+statin: 6.3±1.4 mmHg, P=0.369). However, diastolic BP variability was significantly higher in T2D-statin patients (SD: T2D-statin: 4.1±1.1 mmHg, T2D+statin: 3.1±0.6 mmHg, P=0.013) and MAP variability tended to be higher (SD: T2D-statin: 5.2±1.4 mmHg, T2D+statin: 4.3±0.7 mmHg, P=0.061). Similar results were found for BP range and average real variability. These preliminary findings suggest that statin therapy may have a beneficial effect in lowering BP variability in patients with T2D. Supported by American Heart Association (AHA) - Institutional Award for Undergraduate Student Training - #915555. This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.