Association between grip strength and hypertensive disorders of pregnancy: Prospective analyses in the Tongji–Huaxi–Shuangliu Birth Cohort

BACKGROUND: Hypertensive disorders of pregnancy (HDP) are leading causes of maternal and fetal morbidity and mortality. Although lower grip strength has been linked to higher cardiovascular risk in the general population, evidence on its relationship with HDP remains limited. We aimed to prospectively investigate this association in a large cohort of pregnant women. METHODS: Between March 2017 and January 2020, 6802 pregnant women (mean age ± standard deviation: 26.6 ± 3.7 years) enrolled in the Tongji-Huaxi-Shuangliu Birth Cohort were included in this analysis. Grip strength was measured in early pregnancy (mean gestational week ± standard deviation: 10.3 ± 2.0 weeks) and assessed in three ways: absolute grip strength (AGS) and two relative indices (AGS normalized to body mass index or body weight). Logistic regression models were used to assess the associations between grip strength and the risk of HDP (gestational hypertension or preeclampsia). Multiple metabolic biomarkers (blood lipids, leptin, adiponectin, C-reactive protein, C-peptide, glycated hemoglobin, and homeostatic model assessment of insulin resistance) were measured among 638 women at enrollment. RESULTS: A total of 180 women developed HDP during pregnancy. The adjusted odds ratios (95% confidence intervals) of HDP across increasing quartiles of AGS in early pregnancy were 1.00 (reference), 0.93 (0.63-1.35), 0.67 (0.44-1.00), and 0.35 (0.21-0.56). Odds ratios across quartiles of two relative grip strength (RGS) indices showed similar patterns. Restricted cubic spline analyses indicated a nonlinear association between AGS and HDP risk (P for nonlinearity = 0.014). The risk plateaued at lower AGS levels but showed a linear inverse association above a threshold of 18.1 kg. In contrast, the two relative measures showed linear associations with HDP risk (P for nonlinearity ≥0.164). Additionally, higher RGS was generally correlated with favorable metabolic profiles (e.g., lower levels of low-density lipoprotein cholesterol, triglycerides, and C-reactive protein). CONCLUSION: Grip strength in early pregnancy was inversely associated with the risk of HDP, and RGS may serve as a simple and useful measure for risk stratification.