Does a healthy diet reduce the risk of high blood pressure in women who had a history of gestational diabetes? Also, a new meta-analysis indicates that a way to predict preeclampsia may be possible. Plus: A look at the impact of preconception lifestyle on pregnancy loss.
A healthy diet after pregnancy may help reduce risk of high blood pressure in women who had gestational diabetes mellitus (GDM), according to a new report in Hypertension. The results are from a prospective cohort study funded by the National Institutes of Health (NIH) Eunice Kennedy Shriver National Institute of Child Health and Human Development, the National Institute of Diabetes and Digestive and Kidney Diseases, and the National Cancer Institute.
Researchers conducted the analysis based on data from 3818 women with a history of GDM who were part of the Nurses’ Health Study II and were followed up from 1989 to 2011. Self-administered questionnaires previously validated by medical record review were used to identify incident hypertension.
Scores for adherence for following the alternative Mediterranean diet, the Dietary Approaches to Stop Hypertension (DASH), and the alternative Healthy Eating index 2010 (AHEI) were computed for each woman. The associations between dietary scores and hypertension were evaluated using Cox proportional hazard models.
Over the course of 18.5 years of follow up, 1069 cases of incident hypertension were reported. After adjustment for major risk factors for hypertension, the alternative Mediterranean and DASH diets and the AEHI were significantly inversely associated with risk of hypertension: hazard ratios and 95% confidence interval comparing the extreme quartiles (highest vs lowest) 0.76 (0.61–0.94; P for linear trend =0.03) for AHEI score, 0.72 (0.58–0.90; P for trend =0.01) for Dietary Approach to Stop Hypertension score, and 0.70 (0.56–0.88; P for trend =0.002) for alternative Mediterranean diet score.
The researchers concluded that sticking to a healthful dietary pattern reduces the risk of developing hypertension among women who have a history of GDM.
A way to predict preeclampsia?
A new systematic review and meta-analysis of cohort studies published in BMJ may improve identification of women at risk of developing preeclampsia.
The researchers used PubMed and Embase databases to identify cohort studies from 2000 to 2015 with ≥1000 participants that evaluated the risk of preeclampsia in association with a common and generally accepted clinical risk factor and who were assessed at ≤16 weeks’ gestation. Two reviewers extracted the data from the studies. Pooled event rate and pooled relative risk (pRR) for preeclampsia were calculated for each of the 14 risk factors.
The analysis covered 92 studies and 25,356,688 pregnancies. The pRR for each risk factor significantly exceeded 1.0 with the exception of prior intrauterine growth restriction. Women who had antiphospholipid antibody syndrome had the highest pooled rate of preeclampsia (17.3%, 95% confidence interval [CI] 6.8% to 31.4%). Women with a history of preeclampsia had the greatest pRR (8.4, 95% CI 7.1 to 9.9). Chronic hypertension was associated with the second highest pooled rate (16.0%, 95% CI 12.6% to 19.7%) and pRR (5.1, 95% CI 4.0 to 6.5) for preeclampsia.
Other prominent risk factors included use of assisted reproductive technology (pooled rate 6.2%, 95% CI 4.7% to 7.9%; pRR1.8, 95% CI 1.6 to 2.1); prepregnancy body mass index >30 (7.1%, 95% CI 6.1% to 8.2%; 2.8, 95% CI 2.6 to 3.1); and pregestational diabetes (11.0%, 95% CI 8.4% to 13.8%; 3.7, 95% CI 3.1 to 4.3).
One of the limitations of the meta-analysis was that 15 of the 92 studies did not provide a formal definition of preeclampsia. When preeclampsia was based on the standard clinical definition, the rate was much higher than when rates were based on International Classification of Diseases coding. Differing definitions of certain risk factors, such as renal disease, also served as an inconsistency. The investigators were also unable to account for any interaction between separate risk factors.
The researchers concluded that there are several clinical risk factors that can used, alone or in combination, to identify women in early pregnancy who may be at high risk of preeclampsia. These risk factors, they said, may prove useful in creating a clinical prediction model for preeclampsia.
Does preconception lifestyle play a role in pregnancy loss?
The impact of preconception diet and habits may have an impact on miscarriage risk, according to a recent prospective cohort study published in Fertility and Sterility.
The researchers looked at 344 couples with a singleton pregnancy who were from 16 counties in Michigan and Texas. The couples were followed daily through 7 weeks’ gestation. Each couple recorded daily their use of cigarettes, caffeinated and alcoholic beverages, and multivitamins.
The women used ovulation detection and digital pregnancy tests and pregnancy loss was noted by conversion to a negative pregnancy test, onset of menses, or clinical confirmation, depending on gestation. Proportional hazards regression was used to estimate hazard ratios for the couples’ lifestyles during 3 windows: preconception, early pregnancy, and periconception.
Of the 344 women, 98 (28%) experienced an observed pregnancy loss. During the preconception window, the researchers found an association between such losses and maternal age ≥35 (1.96, 95% confidence interval [CI] 1.13–3.38), consumption of >2 daily caffeinated beverages by both members of a couple (1.73, 95% CI 1.10–2.72; and 1.74, 95% CI 1.07–2.81, respectively), and lack of the woman’s adherence to a vitamin regimen (0.45, 95% CI 0.25-0.80). The lifestyle findings were similar during the other 2 windows.
The authors concluded that a couple’s preconception lifestyle behaviors were linked to pregnancy loss, although the risk could be significantly mitigated if the woman adhered to taking a multivitamin. They believe that their findings support further study and refinement of preconception counseling on lifestyle factors.