Relationship between urinary tract stones and incident hypertension among postmenopausal women: Results from the women's health initiative.

PURPOSE: To evaluate: whether self-reported urinary tract stones (UTS) are associated with incident hypertension in postmenopausal women in the Women's Health Initiative; potential effect modification by diet-related inflammation and lifestyle factors; whether recurrent UTS further increased risk.

METHODS

We conducted a prospective cohort study of 100,562 postmenopausal women aged 50-79 years without baseline hypertension. UTS were self-reported and modeled as a time-varying exposure. Effect modification by the dietary inflammatory index (DII®) and energy-adjusted DII (E- DIITM), physical activity, alcohol consumption, and neighborhood socioeconomic status were evaluated. Incident hypertension was assessed using Cox hazards models adjusted for age and metabolic, lifestyle, socioeconomic, and dietary factors.

RESULTS

In unadjusted models, UTS were associated with higher incident hypertension risk (HR = 1.29; 95% CI: 1.11-1.45, p = 0.001) and after full adjustment(HR = 1.16; 95% CI: 1.02-1.35; p = 0.05). DII/E-DII did not significantly modify the association (interaction p > 0.20), while physical activity did (interaction p = 0.03). Recurrent UTS increased hypertension risk versus no stone history (HR = 1.14; 95% CI: 1.02-1.28; p = 0.03), but not versus a single episode (HR = 1.09; 95% CI: 0.96-1.23; p = 0.18).

CONCLUSION

UTS were associated with a modestly increased risk of hypertension in postmenopausal women.