Effect of Aromatherapy on Anxiety and Physiological Parameters in Patients Undergoing Coronary Angiography: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

Anxiety is common among patients undergoing coronary angiography and may adversely affect physiological stability and procedural outcomes. Although pharmacological anxiolytics are commonly used, they may be associated with undesirable adverse effects. Aromatherapy has been proposed as a complementary intervention with potential anxiolytic benefits. This systematic review and meta-analysis evaluated the effectiveness of inhalational aromatherapy in reducing anxiety and improving physiological parameters in patients undergoing coronary angiography. The review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 guidelines and registered in the International Prospective Register of Systematic Reviews (CRD420261329600). A comprehensive search of PubMed/MEDLINE, Embase, Scopus, and Cochrane CENTRAL was performed from database inception to October 2025. Randomized controlled trials comparing inhalational aromatherapy with standard care or placebo before coronary angiography were included. Outcomes of interest were anxiety scores, systolic and diastolic blood pressure, heart rate, and respiratory rate. Data were pooled using a random-effects model and reported as standardized mean differences (SMDs) or mean differences with 95% confidence intervals (CIs). Three randomized controlled trials involving 274 participants met the inclusion criteria. Baseline anxiety levels were comparable between the aromatherapy and control groups (SMD 0.06, 95% CI -0.18 to 0.30; I2 = 3%). Aromatherapy significantly reduced postprocedural anxiety (SMD -0.66, 95% CI -1.20 to -0.13; I2 = 79%). No statistically significant differences were observed between groups in systolic blood pressure, diastolic blood pressure, heart rate, or respiratory rate. These findings suggest that aromatherapy may be an effective complementary intervention for reducing anxiety in patients undergoing coronary angiography, although its effects on physiological parameters remain uncertain. Larger, high-quality randomized controlled trials are needed to confirm these findings.