Abstract | Cilj istraživanja: pronaći najbolje dokaze o efektima suplementacije vitaminom C, samim ili u kombinaciji sa drugim suplementima na ishode trudnoće, štetne događaje, i nuspojave. Materijal i metode: najprije je na stranici Cochrane knjižnici pronađen Cochrane sustavni pregled koji je bio podloga ovog istraživanja. Potom su pretražene stranice MEDLINE (Pub-
Med), DARE i CENTRAL u potrazi za novim sustavnim pregledima i randomiziranim kontroliranim pokusima, koji su noviji datumi od pronađenog Cochrane pregleda, ali imaju iste ulazne i izlazne kriterije. Nakon pronalaženja radova, napravljena je R-AMSTAR procjena kvalitete sustavnih pregleda.
Rezultati: U Cochrane sustavnom pregledu obrađeno je 5 studija koje su uključivale 766 žena. Nije pronađena razlika između žena suplementiranih vitaminom C, samim ili u kombinaciji s nekim drugim dodatkom, u odnosu na placebo za rizik od mrtvorođenih (RR
0.87, 95% CI 0.41-1.87, 3 studije, 539 žena); perinatalne smrti (RR 1.16, 95 % CI 0.61-2.18, 2 studije, 238 žena); porođajne težine ( (WMD)-139.00 g, 95 % CI-517.68 do 239.68, jedna studija, 100 žena) ili restrikcije intrauterinog rasta (RR 0.72, 95 % CI 0.49 do 1.04, 2 studije,
383 žene). Neke studije su pokazale povećan rizik prijevremenog poroda kod žena suplementiranih vitaminom C (RR 1.38, 95 % CI 1.04 do 1.82, 2 studije, 583 žena). Nije pronađena razlika kod neonatalne smrti (RR1.73, 95% CI 0.25 do 12.12, 2 studije, 221 žena). Za preeklampsiju nije pronađena razlika između vitaminske i placebo grupe (RR0.52, 95 % CI 0.23 do 1.20, 4 studije, 710 žena). Pronađeno je još 5 studija, od kojih ni jedna nije pokazala smanjenje rizika od preeklampsije suplementacijom vitaminom C. Jedna studija je pokazala smanjenje porođajne težine u grupi koja je primala vitamin C (RR 1.15, 95% CI,
1.02 – 1.30). U jednoj studiji je prijevremena ruptura membrana (PROM) je bila češća u vitaminskoj grupi (RR 1.89, 95% CI, 1.11 – 3.23; p=.015). Napravljena je R-AMSTAR procjena sustavnog pregleda, te je Cochrane sustavni pregled skupio 36 bodova. |
Abstract (english) | Diploma Thesis Title: Finding evidence of efficacy and safety of vitamin C in pregnancy: systematic review approach.
Objectives: Finding the best available evidence of efficacy and safety of vitamin E in pregnancy.
Material and Methods: „Vitamin C in pregnancy“ systematic review was found by searching the Cochrane Library website. We searched MEDLINE (PubMed), DARE and CENTRAL databases in order to find new randomised controlled trials and systematic reviews, following the same criteria that were used in Cochrane systematic review. After the search, we made quality assessment of all systematic reviews using R-AMSTAR tool.
Results: Five trials, involving 766 women, are included in this review. No difference was seen between women supplemented with vitamin Calone or combined with other supplements compared with placebo for the risk of stillbirth (relative risk (RR) 0.87, 95% confidence intervals (CI) 0.41 to 1.87, three trials, 539 women), perinatal death (RR 1.16, 95% CI 0.61 to 2.18, two trials, 238 women), birthweight (weighted mean difference (WMD) -139.00 g, 95% CI -517.68 to 239.68, one trial, 100 women) or intrauterine growth restriction (RR 0.72, 95% CI 0.49 to 1.04, two trials, 383 women). Women supplemented with vitamin C alone or combined with other supplements were at increased risk of giving birth preterm (RR 1.38, 95% CI 1.04 to 1.82, three trials, 583 women). Significant heterogeneity was found for neonatal death and pre-eclampsia. No difference was seen between women supplemented with vitamin C combined with other supplements for the risk of neonatal death (RR 1.73, 95% CI 0.25 to 12.12, two trials, 221 women), using a randomeffects model. For pre-eclampsia, women supplemented with vitamin C combined with other supplements were at decreased risk when using a fixed-effect model (RR 0.47, 95% CI 0.30 to 0.75, four trials, 710 women); however, this difference could not be demonstrated when using a random-effects model (RR 0.52, 95% CI 0.23 to 1.20, four trials, 710 women).
We found five another RCTs. No difference was found between women supplemented with vitamin E compared with placebo for the risk od preeclampsia in any of them. In one of the studies, more low birthweight babies were born to women who took antioxidants than to controls (RR 1.15, 95% CI, 1.02 – 1.30). In another study, premature rupture of the membranes (PROM) was more frequently observed in the study drug group (RR 1.89, 95% CI, 1.11 – 3.23). Total R-AMSTAR score for Cochrane systematic review was 36, and for another review 32 points. |