A comparative study of efficacy of antihypertensive drugs andfeto-maternal outcome in the treatment of pregnancy induced hypertension

Abstract

Background: Hypertensive disorders are the most common medical disorders in pregnancy contributing significantly to maternal and perinatal mortality and morbidity worldwide. The incidence is around 3-10% of all pregnancies. The aim of antihypertensives is to reduce, stabilize the blood pressure and thus minimize the risks such as placental abruption, maternal cardiac failure, cerebral hemorrhage; but they should not have any adverse effects on the uteroplacental circulation and the fetus. Antihypertensive drugs are often used to lower blood pressure to prevent this progression to adverse outcomes for the mother and the fetus. The risk of developing severe hypertension is reduced to half by using antihypertensive medications. The aim and objectives of the study was a comparative study of the efficacy of methyldopa, nifedipine versus labetalol and the feto-maternal outcome in gestational hypertension in a tertiary care referral centre. Methods: A prospective study on 240 outpatients as well as inpatients of the antenatal ward of Obstetrics and Gynaecology department of Chhattisgarh Institute of Medical Sciences, Bilaspur which is a tertiary care referral hospital. The patients randomly divided in three groups. The first group received alpha-methyl dopa 250mg tds, second 20 mg bd nifedipine and the third one labetalol 100mg bd. Mean arterial pressure calculated by systolic BP +2 DBP/3.The fall in BP calculated along with time required, dose of drug required, spontaneous/ induced labour or caesarean section, adverse maternal and the fetal outcome was observed. Results: Maximum number of patients that is 145(60.42%) patients belonged to the age group of 19 to 24 years and were primigravida (70.42%) presenting at 33-37 weeks of gestation. Significant fall in MAP was seen in patients receiving nifedipine and labetalol. Mean time to control blood pressure is 46.32 hrs in methyldopa group, 30.44hrs in nifedipine group and 37.24 hrs in labetalol group. 103 (42.9%) patients had normal delivery whereas 137 (57.1%) required a caesarian section, higher rate of spontaneous labour in nifedipine and labetalol group. Most common sideeffect observed was headache; the other side effects included drowsiness, more in patients treated with methyldopa, weakness, more in patients treated with labetalol. The fetal outcome was better with labetalol and nifedipine than methyl-dopa group. Conclusions: The decreased association from maternal and fetal side-effects, the comparatively better hypotensive action indicates that labetalol and nifedipine is suitable for use during pregnancy. Labetalol is safer, quicker in achieving adequate control of blood pressure with considerable prolongation of the duration of pregnancy with fewer side effects on the mother as well as the neonate when used in the management hypertensive disorders of pregnancy.

Study on ocular fundus changes in pregnancy induced hypertension in a tertiary care hospital

“…This could be again due to the arteriolar sclerosis in aged patients who are multigravida. Similar results were seen in a study by Babbar et al which showed 70.42% of the cases of pregnancy induced hypertension were primigravidas, while the remaining were multigravida [14] .…”

A prospective, parallel group, open label, observational study to compare efficacy and feto-maternal outcomes in treatment of pregnancy induced hypertensive patients

“…12 In our present study, incidence of PIH occurs between the age group 21-24 in all the three groups (50% in nifedepine group, 50% in Labetalol group,47.5% in methyldopa group) which was similar to study conducted by Babbar et al and similarly there were no significant difference was observed in age distribution in the groups. In our study majority of them (35%) were primiparities, and (55.83%) were primigravidas which was similar to study conducted by Sajith et al 13,14 Most patients with PIH in all three groups belonged to 33-37 weeks gestational age which was similar to study conducted by Babbar et al 13 The mean time to achieve target BP was shown less in labetalol group (65.96 hrs with SD 29.51) when compare to methyldopa and nifedepine. The similar studies have been seen in Babbar et al 13 In present study, the maximum doses required to achieve target BP were in between 4-6 doses/day among all the treatment groups.…”

“…Adverse effects of drugs in which patients under nifedipine group shows tachycardia as common 11 (27.5%) ADR while labetalol group commonly shows weakness 15 (37.5%) methyldopa group commonly shows drowsiness 14 (35%), similar studies were observed in Babbar et al, in which most common adverse effects were occipital headache (3-9%), postural hypotension (3-8%), tachycardia (4-11%), and depression (2-7%) which was similar to study conducted by Babbar et al 13 …”

Which antihypertensive treatment is better for mild to moderate hypertension in pregnancy?

“…β blockers and calcium channel blockers were found to be more effective than methyldopa in avoiding severe hypertension (risk ratio 0.70 (0.56 to 0.88), 11 trials, 638 women) 11. Two trials (274 women) directly compared labetalol and nifedipine (table 2, with full details in supplementary table 1) 1213. The sample sizes are too small to provide definitive evidence on clinical outcomes.…”