Presence of arachidonoyl-carnitine is associated with adverse cardiometabolic responses in hypertensive patients treated with atenolol

Introduction: Atenolol, a commonly prescribed β blocker for hypertension, is also associated with adverse cardiometabolic effects such as hyperglycemia and dyslipidemia. Knowledge of the mechanistic underpinnings of these adverse effects of atenolol is incomplete. Objective: We sought to identify biomarkers associated with risk for these untoward effects of atenolol. We measured baseline blood serum levels of acylcarnitines (ACs) that are involved in a host of different metabolic pathways, to establish associations with adverse cardiometabolic responses after atenolol treatment. Methods: Serum samples from Caucasian hypertensive patients (n = 224) who were treated with atenolol in the Pharmacogenomic Evaluation of Antihypertensive Responses (PEAR) study were interrogated using a quantitative LC/MS assay for a large number of unique ACs in serum. For the 23 ACs that were detected in serum from ≥80 % of all patients, we conducted linear regression for changes in cardiometabolic factors with baseline AC levels, baseline cardiometabolic factors, age, sex, and BMI as covariates. For the 5 ACs that were detected in serum from 20 to 79 % of the patients, we similarly modeled changes in cardiometabolic factors, but with specifying the AC as present/absent in the regression. Results: Among the 28 ACs, the presence (vs. absence) of arachidonoyl-carnitine (C20:4) was significantly associated with increased glucose (p = 0.0002), and was nominally associated with decreased plasma HDL-C (p = 0.017) and with less blood pressure (BP) lowering (p = 0.006 for systolic BP, p = 0.002 for diastolic BP), after adjustment. Conclusion: Serum level of C20:4 is a promising biomarker to predict adverse cardiometabolic responses including glucose and poor antihypertensive response to atenolol.