Association of renin-angiotensin-aldosterone system genetic polymorphisms with maternal hypotension during spinal anaesthesia for caesarean delivery: a retrospective cohort study. (November 2020)

• Record Type: Journal Article
• Authors: Tan, H.S.; Gan, Y.T.; Tan, E.C.; Nagarajan, S.; Sultana, R.; Han, N.L.R.; Sia, A.T.H.; Sng, B.L.
• Is Part Of: International journal of obstetric anesthesia. Volume 44(2020)
• Page Start: 3
• Page End: 12
• Publication Date: 2020-11
• Subjects: Hypotension -- Spinal anaesthesia -- Caesarean delivery -- Renin-angiotensin-aldosterone system -- Genetic polymorphism; Obstetrics -- Periodicals; Anesthesia -- Periodicals; Anesthésie en obstétrique -- Périodiques; Anesthesia; Obstetrics; Electronic journals; Periodicals; 617.9682
• DOI: 10.1016/j.ijoa.2020.06.005
• Languages: English
• ISSNs: 0959-289X

Abstract

Highlights: Angiotensin-1 receptor and angiotensin-converting enzyme (ACE) polymorphisms were studied. Aldosterone synthase polymorphisms were studied. Angiotensin type-1 receptor (A1166C) polymorphism was associated with hypotension. A1166C polymorphism did not increase vasopressor or adverse maternal/fetal outcomes. ACE and aldosterone synthase polymorphisms were not associated with hypotension. Abstract: Background: Unless prevented, hypotension occurs in up to 80% of normotensive women undergoing spinal anaesthesia for caesarean delivery. Renin-angiotensin-aldosterone system genetic polymorphisms have been associated with hypertensive disease, but few studies investigated effects on blood pressure regulation under spinal anaesthesia. We postulated that these polymorphisms increased vasodilation and maternal hypotension during spinal anaesthesia. Methods: A retrospective secondary analysis of data from four prospective trials with similar inclusion/exclusion criteria evaluating phenylephrine/ephedrine delivery systems during spinal anaesthesia for elective caesarean delivery. Angiotensin type-1 receptor (AT1R) (A1166C), angiotensin-converting enzyme (ACE) (I/D), and aldosterone synthase CYP11B2 (C344T) polymorphisms were identified from stored specimens. The associations between the polymorphisms and hypotension (systolic blood pressure <80% of baseline), and vasopressor use, were determined by univariable and multivariable regression. Results: Of 556 patients, 378 (68.0%) had hypotension. The AC/CC genotypes of AT1R (A1166C) were associated with hypotension by univariable analysis (OR 2.70, 95% CI 1.38 to 5.28, P =0.004]) and multivariable analysis (OR 3.65, [95% CI 1.68 to 7.94, P =0.004]) after adjustment for age, race, intravenous fluid volume, and block height. No difference in vasopressor use or adverse maternal or fetal outcomes were noted. Baseline characteristics were similar, with the exception of higher baseline blood pressure, block height, and intravenous fluid volume in the hypotensive group. There was no significant association between ACE and CYP11B2 polymorphisms and hypotension. Conclusion: AC/CC genotypes of AT1R (A1166C) polymorphism were associated with maternal hypotension under spinal anaesthesia for caesarean delivery. An association with cardiovascular indices and high-risk parturients should be examined.