Cardiometabolic risk factor management and adherence to antihypertensive therapy in patients with severe obesity prior and after bariatric surgery: a cohort study
M Kunz, J Maalouli Schaar, L Keller, V Keller, L Lauder, F Goetzinger, M Boehm, C Mueller, M Schulz, A Al-Ali, P Scherber, S Hollaender, M Meyer, F MahfoudAbstract
Aims
Patients with obesity continue to experience excess mortality. Inadequate cardiovascular risk factor (CVRF) management and poor medication adherence may contribute to this risk. This study aimed to assess (i) CVRF management, (ii) prescription of guideline-directed medical therapy (GDMT), and (iii) adherence to antihypertensives (AHT) in patients scheduled for bariatric surgery.
Methods
In this cohort study, adults with body mass index (BMI) >35 kg/m2 and arterial hypertension scheduled for bariatric surgery were enrolled. CVRF control was evaluated and adherence was assessed in up to eight serial visits (V1-4 prior and V5-8 after surgery) using liquid chromatography-high-resolution mass spectrometry-based plasma drug analysis. Patients were classified as adherent when all prescribed AHT were detectable, partially adherent when one prescribed AHT was not detectable, and non-adherence either as self-reported or the absence of two or more AHT (for monotherapy, if this AHT was not detectable). Factors associated with adherence were analyzed using mixed-effects logistic regression and Cox proportional hazards models.
Results
Of 80 screened patients, 64 were included (70% women; mean age 48.5±10.4 years; median BMI 50.0 kg/m² [IQR 45.0–54.0]) with 209 available adherence assessments. At V1, guideline-recommended targets were achieved in 27% for blood pressure (SBP 120–129 mmHg), 40% for glycaemic control in patients with diabetes (HbA1c <7%), and 16% for LDL-cholesterol (<100 mg/dL, <70 mg/dL or <55 mg/dL depending on individual cardiovascular risk categories). GDMT for hypertension was prescribed in 59% of patients. At V1, only 6% were fully adherent, 19% partially, and 75% non-adherent. Adherence remained largely stable during follow-up, with few transitions between adherence categories, primarily during in-hospital stays. Median SBP was 137.0 mmHg (IQR 125.0-153.8) at V1 and 130.5 mmHg (IQR 116.8-136.0) at V8 (p=0.0134), while median DBP was 85.0 mmHg (IQR 78.0-94.0) at V1 and 79.0 mmHg (IQR 73.3-89.3) at V8 (p=0.0372). Improvement of BP control was not attributable to improvement in adherence (p=1.0). Diuretic therapy was associated with lower odds of adherence (OR 0.13, 95% CI 0.04-0.47, p=0.0019), while beta-blocker therapy was associated with a reduced hazard of non-adherence over time (time to first non-adherence V1-V8; HR 0.38, 95% CI 0.20-0.73, p=0.0034). Each additional three drug classes were associated with a reduced likelihood of adherence (OR 0.18, 95% CI 0.04-0.71, p=0.0148).
Conclusion
Among patients undergoing bariatric surgery, CVRF control is frequently insufficient, GDMT is inconsistently prescribed, and adherence to AHT is poor. These findings underscore the need for structured adherence-enhancing interventions in this high-risk population.Adherence over time