Association between nocturnal polyuria and 24-h blood pressure fluctuations in males with lower urinary tract symptoms: A multicenter prospective study

Objectives: Nocturnal polyuria (NP) is one of the causes of nocturia that impairs quality of life. It is necessary to consider that NP is latent when the initial treatment for nocturia is unsatisfactory. Therefore, it is important to establish a treatment for NP based on the pathophysiology. We have previously reported the relationship between NP and fluctuation in blood pressure. The present study aimed to investigate the association between NP and 24-h blood pressure fluctuations in a multicenter prospective study.Methods: This study included male patients with lower urinary tract symptoms. We categorized the patients into the nonnocturnal polyuria (non-NP) group (<= 0.33) and the NP group (>0.33) based on the nocturnal polyuria index from the frequency volume chart. We measured the 24-h diurnal blood pressure and compared the two groups.Results: Among 90 patients, 46 in the non-NP group and 44 in the NP group were included. There was no significant difference in the systolic and diastolic blood pressure during waking time between the two groups; however, the degree of systolic blood pressure reduction during sleep time in the NP group was significantly less than that in the non-NP group (p = 0.039). In the multivariate analysis, systolic BP during sleep was significantly associated with NP (OR 0.970, p = 0.028).Conclusion: NP is associated with inadequate nocturnal blood pressure reduction in males, suggesting that reduction in nocturnal blood pressure may lead to improvement in nocturia.