Association Between Body Mass Index and the Efficacy of Calcium Channel Blockers for Hypertension in Cardiovascular Disease Patients

BACKGROUND: Hypertension, or high blood pressure, is a major risk factor for cardiovascular diseases (CVDs) worldwide. Variations in body mass index (BMI) may influence the efficacy of calcium channel blockers (CCBs) by affecting drug metabolism, vascular resistance, and inflammatory responses associated with adipose tissue. OBJECTIVE: This study aims to evaluate the association between BMI and the short-term efficacy of CCBs in managing hypertension among patients with CVDs over a six-month follow-up period. METHODOLOGY: This prospective observational study was conducted at the Department of General Internal Medicine, Royal Alexandra Hospital, Glasgow, UK, from June 2023 to June 2024, enrolling 220 patients diagnosed with hypertension and at least one underlying cardiovascular condition, such as coronary artery disease, heart failure, or atrial fibrillation. Patients were categorized into BMI groups based on the World Health Organization (WHO) classification, and all were prescribed CCBs either as monotherapy or in combination with other antihypertensive medications. Blood pressure was measured using an automated sphygmomanometer with follow-up ambulatory monitoring, while lipid levels were assessed via fasting blood samples. RESULTS: The study involved 220 participants, categorized into four BMI groups: underweight (n = 40), normal weight (n = 60), overweight (n = 60), and obese (n = 60). Underweight patients had a baseline systolic/diastolic blood pressure of 150/95 mmHg, which decreased to 135/85 mmHg, showing a reduction of 15/10 mmHg. Normal weight patients experienced a drop from 145/90 mmHg to 130/80 mmHg, overweight patients from 155/95 mmHg to 140/85 mmHg, and obese patients from 160/100 mmHg to 145/90 mmHg, all with the same reduction of 15 mmHg in systolic and 10 mmHg in diastolic pressure. Low-density lipoprotein (LDL) levels decreased in all groups, with a reduction of 5 mg/dL in the underweight (130 to 125 mg/dL) and normal weight (125 to 120 mg/dL) groups, while the overweight (140 to 130 mg/dL) and obese (150 to 140 mg/dL) groups showed a greater reduction of 10 mg/dL. High-density lipoprotein (HDL) levels improved in all categories, increasing by 5 mg/dL in each group. LDL reduction was more pronounced in overweight and obese groups, likely due to metabolic changes associated with higher body fat. Adverse effects, including peripheral edema and dizziness, were more common in higher BMI groups, with a noticeable decline in medication adherence in obese patients. These results suggest that BMI may influence treatment efficacy, particularly in lipid regulation and the occurrence of adverse effects. CONCLUSION: BMI does not significantly affect the blood pressure-lowering efficacy of CCBs in patients with hypertension and CVDs. However, a greater reduction in LDL levels was observed in overweight and obese groups, suggesting that BMI may influence lipid metabolism differently than blood pressure regulation.