Nocturia and Left Ventricular End-Diastolic Pressure in Patients Undergoing Left Sided Cardiac Catheterization

Nocturia, the most common and bothersome of lower urinary tract symptoms, is associated with various cardiovascular (CV) disorders including hypertension and heart failure, suggesting potential relevance as a marker of CV and population health risk. We hypothesized that fluid overload is a major contributor to nocturia accompanying these overlapping but distinct CV disorders and aimed to characterize the relationship between nocturia and volume status. In a single-center observational study, we prospectively recruited 200 patients, age 33-92 years referred for cardiac catheterization to assess left ventricular end diastolic pressure (LVEDP), a hemodynamic parameter reflecting intravascular volume status and obtained nocturia data. Every patient had at least one nighttime void and 152 (76.0%) had higher-frequency nocturia (>2 voids per night), range of actual number of nightly voids (ANV) was 2-5 per night. On logistic regression, higher-frequency nocturia was significantly associated with LVEDP >16 mmHg, older age group, lower LVEF, and edema. As a continuous variable, ANV significantly correlated with LVEDP (r=0.39, p<.0001) and LVEF (r=-.23, p=.0009). On ordinal regression analysis, patients with LVEDP >16 mmHg were 3.50 (95% CI: 1.98, 6.16) times more likely to have a higher ANV as compared to patients with LVEDP ≤ 16 mmHg. Elevated LVEDP is independently associated with nocturia frequency in patients undergoing cardiac catheterization suggesting that nocturia may serve as a noninvasive marker of elevated LV filling pressures and fluid overload. Recognizing nocturia as a marker of CV disease, rather than solely a urologic complaint, may prompt cardiac evaluation in appropriate patients.