Cumulative exposure to remnant cholesterol and new-onset hypertension in middle-aged and older adults: a nationwide prospective cohort study

Background The association between remnant cholesterol (RC) and the risk of developing hypertension remains poorly elucidated. Methods Data were obtained from the China Health and Retirement Longitudinal Study (CHARLS) database, and RC was classified into three types: baseline RC, cumulative RC, and RC change. The RC change was classified using K-means clustering analysis, and the cumulative RC was calculated using the following formula: (RC2011 + RC2015)/2 × time (2015–2011). Logistic regressions were employed to ascertain the correlation between RC change and hypertension. Concurrently, restricted cubic spline regression (RCS) was utilized to investigate the potential non-linear association between the cumulative RC and hypertension. Mediation analysis examined the relationship between BMI and glycated hemoglobin in the development of RC and hypertension. Results During a median follow-up period of 115 months for cohort 1 and 67 months for cohort 2, a total of 2366 cases of hypertension (31.7%) were identified in cohort 1, while cohort 2 exhibited 805 cases (20.3%). A non-linear association between baseline RC and hypertension was observed, with inflection points at 1.16. Individuals in the highest quartile of RC exhibited a heightened propensity for developing hypertension, with an adjusted odds ratio (OR) of 1.52 (p < 0.001) for baseline RC and 1.39 (p = 0.004) for cumulative RC. Although RC change did not exhibit statistically significant differences in risk of hypertension, they did suggest a potential increase in risk. Furthermore, the relationship between RC and hypertension was partially mediated by BMI and HbA1c, with these variables accounting for 36.94% and 7.2% of the total effect, respectively. Conclusions Our results suggest that elevated baseline and cumulative RC levels are associated with an increased risk of new-onset hypertension in middle-aged and older adults, and that baseline RC levels and hypertension are non-linearly related, with an inflection point of 1.16. Additionally, this study found that BMI and glycated hemoglobin mediated the association between RC and incident hypertension.