Assessing the role of dietary acid load in the development of hypertensive disorders during pregnancy: uncovering the association through prospective cohort analysis.

Background: Hypertensive disorders of pregnancy (HDPs) are common complications encountered in pregnancy that affect between 5% and 15% of pregnancies worldwide. Some studies have associated adherence to a diet with a high acid load with an increased risk of HDPs. This study investigates the association between Dietary Acid Load (DAL) and the incidence of preeclampsia, chronic hypertension (HTN), and gestational hypertension (GHTN).

Methods: Pregnant women aged 18 to 45 in the first trimester of pregnancy were selected and followed up until delivery. Diet was evaluated using a 168-question semi-quantitative food frequency questionnaire (FFQ). After calculating the DAL score, the inverse probability weight of the propensity scores, estimated from augmented generalized models, was used to obtain a causal risk ratio (RR) adjusted for potential confounders.

Results: Out of 1,856 women, 92 (4.95%) developed preeclampsia. The potential renal acid load (PRAL) score ranged from - 16.14 to 0.58, while the net endogenous acid production (NEAP) score ranged from 34.61 to 50.15. Multivariable analysis revealed a significant association between PRAL and preeclampsia in the first (aRR: 1.87, 95% CI: 1.01, 3.49, p = 0.048) and third (aRR: 2.01, 95% CI: 1.07, 3.81, p = 0.030) quartiles compared to the reference group (Q2). No significant linear association was found in continuous analyses. For chronic HTN, significant associations were observed in the first (aRR: 2.56, 95% CI: 1.21, 5.42, p = 0.014) and fourth (aRR: 4.79, 95% CI: 2.37, 9.71, p < 0.001) PRAL quartiles, with similar findings for NEAP. Continuous analysis showed a significant linear association between both PRAL and NEAP scores and chronic HTN. Regarding GHTN, significant associations were found in the first (aRR: 1.48, 95% CI: 1.02, 2.16, p = 0.041) and fourth (aRR: 1.88, 95% CI: 1.31, 2.70, p = 0.001) PRAL quartiles, and in Q4 for NEAP (aRR: 1.56, 95% CI: 1.10, 2.21, p = 0.012), with no significant linear association in continuous analysis.

Conclusion: Extremes in DAL, as indicated by PRAL and NEAP, are associated with an increased risk of preeclampsia, chronic HTN, and GHTN, particularly in the highest and lowest quartiles. These findings highlight the potential impact of DAL on HDPs.