European Journal of Cardiovascular Medicine

Hypertensive disorders of pregnancy (HDP) encompass a spectrum of conditions, including gestational hypertension, preeclampsia, and eclampsia. These disorders are among the leading causes of maternal and perinatal morbidity and mortality worldwide¹. In India, the prevalence of HDP is approximately 7.8%, with preeclampsia affecting about 5.4% of pregnancies. Despite extensive research, the exact etiology of HDP remains elusive, though several pathophysiological mechanisms have been proposed².

One such mechanism involves oxidative stress and endothelial dysfunction, which are believed to play pivotal roles in the development of HDP. Oxidative stress can lead to lipid peroxidation, resulting in the accumulation of lipid peroxides that damage endothelial cells. This damage may contribute to the hypertension observed in affected pregnancies³. Furthermore, alterations in lipid metabolism have been implicated in the pathogenesis of HDP. Studies have shown that women with preeclampsia often exhibit elevated levels of total cholesterol, triglycerides, LDL-C, and VLDL-C, along with decreased HDL-C levels⁴.

Magnesium, an essential mineral involved in numerous physiological processes, has also been studied in the context of HDP. It plays a crucial role in vascular tone regulation and endothelial function⁵. Hypomagnesemia has been associated with increased vascular resistance and hypertension. Some studies have reported significantly lower serum magnesium levels in women with HDP compared to normotensive pregnant women. However, the relationship between serum magnesium levels and HDP remains a subject of ongoing research⁶.

Given the potential roles of dyslipidemia and hypomagnesemia in the development of HDP, this study aims to evaluate and compare serum magnesium levels and lipid profiles among normotensive pregnant women and those with HDP. Understanding these associations may provide insights into the pathophysiology of HDP and aid in the development of preventive and therapeutic strategies

A prospective case-control study was conducted over a six-month period at the Department of Obstetrics and Gynecology, Tertiary Care Teaching Hospital. The study was approved by the Institutional Ethical Committee, and informed consent was obtained from all participants.

Study Population

The study included 100 pregnant women beyond 32 weeks of gestation. The case group comprised 50 women diagnosed with HDP, including gestational hypertension, preeclampsia, and eclampsia, based on the criteria established by the National High Blood Pressure Education Program. The control group consisted of 50 normotensive pregnant women matched for gestational age.

Inclusion Criteria

• Pregnant women with gestational age >32 weeks.
• Singleton pregnancies.
• For cases: Diagnosed with HDP.
• For controls: Normotensive throughout pregnancy.

Exclusion Criteria

• Multiple pregnancies.
• Pre-existing chronic hypertension, diabetes mellitus, renal or hepatic disorders.

Data Collection Procedure

Detailed obstetric and medical histories were obtained from all participants. Fasting venous blood samples (5 mL) were collected and analyzed for serum magnesium using spectrophotometric methods. Lipid profiles, including total cholesterol, triglycerides, HDL-C, LDL-C, and VLDL-C, were measured using enzymatic colorimetric assays. All laboratory analyses were conducted in the hospital's central laboratory following standard protocols.

Statistical Data Analysis

Data were entered into Microsoft Excel and analyzed using SPSS version 25. Continuous variables were expressed as mean ± standard deviation. Comparisons between groups were made using the independent t-test for normally distributed variables and the Mann-Whitney U test for non-normally distributed variables. A p-value of <0.05 was considered statistically significant.

Table 1: Demographic Characteristics of Study Participants

Table 2: Comparison of Serum Magnesium Levels

Table 3: Lipid Profile Comparison

Table 4: Correlation of Serum Magnesium with Lipid Profile (HDP Group)

Table 5: Distribution of Hypertensive Disorders and Associated Profiles

Hypertensive disorders of pregnancy, particularly preeclampsia, are complex in origin, involving endothelial dysfunction, inflammation, and metabolic disturbances. This study reinforces the growing body of evidence that suggests a significant role of altered mineral and lipid metabolism in the pathogenesis of HDP.

The significantly lower serum magnesium levels observed in the HDP group suggest that hypomagnesemia may contribute to the elevated vascular tone seen in these patients. Magnesium functions as a natural calcium antagonist, promoting vasodilation and preventing smooth muscle contraction¹⁰. Its deficiency can exacerbate vasoconstriction and increase blood pressure, aligning with findings from past studies (Kisters et al., 2000; Jain et al., 2010) ^11,12.

Additionally, this study showed a profound alteration in lipid metabolism in HDP. Elevated levels of total cholesterol, triglycerides, LDL-C, and VLDL-C, coupled with reduced HDL-C, are indicative of dyslipidemia. These changes are consistent with those reported by Ray et al. (2006) ¹³, who emphasized the role of lipid peroxidation and oxidative stress in endothelial damage.

The inverse correlation between serum magnesium and lipid parameters observed in this study suggests that magnesium deficiency may also exacerbate lipid abnormalities, contributing further to endothelial dysfunction and hypertension¹⁴. The degree of dyslipidemia was more severe in women with preeclampsia than in those with gestational hypertension, indicating a possible dose-response relationship between lipid imbalance and disease severity¹⁵.

Our results underscore the clinical importance of early screening for both serum magnesium and lipid profile in pregnant women, especially those at risk for HDP. Interventional studies involving magnesium supplementation or lipid-lowering agents in high-risk populations may help establish their roles in prevention or management¹⁶.

Limitations of the current study include a relatively small sample size and the inability to establish causation due to its observational design. However, its strength lies in the comprehensive comparison of both serum magnesium and lipid profiles within the same cohort, enabling a better understanding of their interplay.

This study demonstrates that pregnancy-related hypertensive disorders are associated with significant alterations in serum magnesium and lipid profiles. Women with HDP had lower serum magnesium and higher atherogenic lipid levels compared to normotensive pregnant women. Routine monitoring of these parameters during antenatal visits may serve as early indicators of developing HDP. Early detection can facilitate prompt interventions, potentially mitigating adverse maternal and fetal outcomes. Future research with larger cohorts and interventional designs is warranted to explore the therapeutic implications of these findings.

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