Comparison of carotid intima media thickness between women with history of preeclampsia and normal pregnancy: a meta-analysis of systematic review – The Egyptian Journal of Internal Medicine

Trial flow and study characteristic

The combined search of PubMed, Google Scholar, and SAGE Journals, which also included some hand-searching of relevant cardiology and obstetrics journals, retrieved 1073 articles. After discarding a number of duplicates retrieved by individual searches and reviewing all titles and abstracts, many studies were excluded because they were not relevant with our topics, or did not investigate any of the outcomes of interest to this study, or were animal or basic research studies or review articles. Overall, nine studies, enrolling a total of 965 patients, were included in this analysis (Fig. 1).

PRISMA flowchart of studies’ selection

Of the 1073 research articles obtained through search using predefined keywords, nine research articles were obtained that met the inclusion and exclusion criteria and had passed the eligibility test. The nine studies consisted of various ethnicities, races, and locations. One article from China, Norway, Canada, the Netherlands, Sweden, and Croatia and three articles from Turkey (Table 1).

Funnel plot and forest plot comparison of CIMT between women with a history of preeclampsia and normal pregnancy

Four study articles with CIMT differed significantly in the preeclampsia group compared to the control group, while five study articles did not show any significant difference between the two study groups as seen in the Funnel Plot (Fig. 2).

Funnel plot for testing publication bias

Goynumer et al. [9] performed CIMT examination 1–2 years post-partum in 34 patients with preeclampsia and 42 control patients. CIMT examination was performed on the right and left CCA segments. The mean value of CIMT was 0.66 ± 0.07 mm in the preeclampsia group and 0.62 ± 0.06 in the control group. CIMT in the preeclampsia group was significantly higher than the control group (p value 0.025) [9].

Yuan et al. [21] performed a CIMT examination 18 months post-partum in 22 preeclampsia patients and 28 control patients. The CIMT examination was performed on the right CCA segment. The mean value of CIMT was 0.459 ± 0.095 mm in the preeclampsia group and 0.351 ± 0.085 in the control group. CIMT in the preeclampsia group was significantly higher than the control group (p value 0.0001) [21].

Sandvik et al. [18] performed a 10-year post-partum CIMT examination in 89 preeclampsia patients and 69 control patients. CIMT examination was performed on the right and left CCA segments. The mean value of CIMT was 0.49 ± 0.07 mm in the preeclampsia group and 0.50 ± 0.06 in the control group. CIMT in the preeclampsia group was not significantly different from the control group (p value 0.67) [18].

McDonald et al. [15] performed CIMT examinations 19–28 years post-partum in 109 preeclampsia patients and 219 control patients. CIMT examination was performed on the right and left CCA segments. The mean value of CIMT was 0.649 ± 0.120 mm in the preeclampsia group and 0.646 ± 0.111 in the control group. CIMT on 59 preeclampsia group was not significantly different from the control group (p value 1.00) [15].

Blaauw et al. [3] performed CIMT examination 4–5 years post-partum in 17 preeclampsia patients and 16 control patients. CIMT examination was performed on the right and left CCA segments. The mean value of CIMT was 0.61 ± 0.08 mm in the preeclampsia group and 0.59 ± 0.06 in the control group. CIMT in the preeclampsia group was not significantly different from the control group (p value 0.4) [3].

Akhter et al. [1] conducted CIMT examination on 42 preeclampsia patients and 44 control patients aged 40–50 years who were registered in the registry of Uppsala University Hospital, Norway. CIMT examination was performed on the left CCA segment. The mean value of CIMT was 0.63 ± 0.12 mm in the preeclampsia group and 0.61 ± 0.12 in the control group. CIMT in the preeclampsia group was not significantly different from the control group [1].

Ceylan et al. [6] performed 5 years post-partum CIMT examination in 46 preeclampsia patients and 38 control patients. The CIMT examination was performed on the right CCA segment. The mean value of CIMT was 0.58 ± 0.14 mm in the preeclampsia group and 0.50 ± 0.10 in the control group. CIMT in the preeclampsia group was significantly higher than the control group (p value 0.004) [6].

Aykas et al. [2] performed 5 years post-partum CIMT examination in 25 preeclampsia patients and 20 control patients. CIMT examination is performed on the right and left segments. The mean value of CIMT was 0.64 ± 0.12 mm in the preeclampsia group and 0.52 ± 0.08 in the control group. CIMT in the preeclampsia group was significantly higher than the control group (p value 0.001) [2].

Habek et al. [10] performed a CIMT examination 6 months post-partum in 55 preeclampsia patients and 50 control patients. CIMT examination was performed on the right and left CCA segments. The mean value of CIMT was 0.419 ± 0.29 mm in the preeclampsia group and 0.412 ± 0.43 in the control group. CIMT in the preeclampsia group was not significantly different compared to the control group [10].

The combined total mean difference between the studies and their confidence intervals is depicted on the forest plot (Fig. 3). The heterogeneity test of the nine research articles was 79.71%, indicating that the nine selected research articles were heterogeneous. The random effect test comparison of CIMT in the preeclampsia and control groups showed p = 0.01 with a confidence interval of 0.08 to 0.70. These results indicate that there is a significant difference between CIMT in the preeclampsia group and the control group, where the preeclampsia group has a greater CIMT value.

Forest Plot for the effect of CIMT on preeclampsia