Herbal medicine for insomnia in elderly with hypertension: A systematic review and meta-analysis

Introduction: Herbal medicine (HM) may be beneficial for geriatrics with multiple pathological conditions. The objective of this study was to systematically analyze the effectiveness and safety of HM for insomnia in the hypertensive elderly. Methods: Thirteen databases were comprehensively searched from their inception dates to August 28, 2018, to identify relevant randomized control trials (RCTs). The results of meta-analyses were presented as relative risk (RR) or mean difference (MD) with 95% confidence intervals. The quality of evidence (QoE) was evaluated using the GRADE approach. Results: Eight RCTs were included in this review. Based on routine antihypertensive therapies in most cases, compared to the hypnotics group, HM group had a significantly higher total effective rate (TER) for improvement of insomnia (RR 1.24 [1.12, 1.39]). Compared to no intervention group, HM group showed a significantly higher TER for improving insomnia (RR 1.70 [1.25, 2.33]), and lowering systolic (MD -5.63 mmHg [-7.18, -4.09]) and diastolic blood pressures (MD -4.40 mmHg [-5.63, -3.18]). Pittsburgh sleep quality index (MD -4.11 [-5.72, -2.50]), Zung self-rating anxiety scale (MD -6.60 [-7.79, -5.41]), and Zung self-rating depression scale (MD -6.15 [-7.43, -4.87]). There was no significant difference in the incidence of adverse events between the HM and no intervention groups. The QoE ranged from "Very low" to "Moderate." Conclusion: HM might have some beneficial effects including improving insomnia, blood pressure, and mental health, for the hypertensive elderly with insomnia. Since the methodological quality of the included studies and QoE were not high, well-designed RCTs are important to confirm these results.