ObjectiveHypertension is a common and modifiable cardiovascular risk factor. The triglyceride-total cholesterol-body weight index is a novel metabolic indicator derived from routine clinical measurements, but its association with hypertension remains unclear.MethodsThis longitudinal cohort study used data from 5,731 middle-aged and older adults from the English Longitudinal Study of Ageing, with cross-sectional, prospective, and trajectory analyses. Hypertension was defined as a mean systolic blood pressure ≥140 mmHg, a mean diastolic blood pressure ≥90 mmHg, antihypertensive medication use, or self-reported physician-diagnosed hypertension. For the prospective analysis, participants without hypertension at baseline were followed for a median of 12 years. For the trajectory analysis, repeated triglyceride-total cholesterol-body weight index measurements from previous waves were used to identify long-term triglyceride-total cholesterol-body weight index patterns and assess their associations with hypertension risk. Subgroup analyses and propensity score matching were performed to assess the robustness of the findings.ResultsIn the cross-sectional analyses, each one-unit increase in log-transformed triglyceride-total cholesterol-body weight index was associated with 43% higher odds of hypertension (adjusted odds ratio = 1.43, 95% confidence interval: 1.31-1.55). In the prospective analyses, baseline triglyceride-total cholesterol-body weight index predicted incident hypertension (adjusted hazard ratio = 1.16, 95% confidence interval: 1.05-1.28). Trajectory analyses identified low, moderate, and high triglyceride-total cholesterol-body weight index patterns, showing a graded increase in hypertension risk. Compared with the low-trajectory group, the high-triglyceride-total cholesterol-body weight index group had 69% higher odds of hypertension (adjusted odds ratio = 1.69, 95% confidence interval: 1.37-2.09, p < 0.001).ConclusionTriglyceride-total cholesterol-body weight index was independently and positively associated with the risk of hypertension and may provide a simple measure of metabolic burden relevant to early risk stratification.