Analysis of multicollinearity with linear regression revealed a variance inflation factor (VIF) for age, systolic blood pressure, diastolic blood pressure, Ni, diabetes mellitus and sleep apnea of 1.195, 1.784, 1.886, 1.017, 1.018 and 1.046 respectively. As all values were less than the most conservative VIF cutoff of 2.5, this informed us that there were no interactions or buffer effects present amongst independent variables and supported their use in the multivariate model. Of the 280 men analyzed, 75 were found to have 0 or 1 nightly void on bladder diary and 205 men were found to have ≥ 2 nightly voids. Median age of the studied population was 68.0 (63.0, 75.0) years. On multivariate analysis of the entire patient cohort without including Ni as a covariate, elevated blood pressure was predictive of clinically significant nocturia but did not reach statistical significance (OR 1.311, 95% CI 0.754 – 2.278, p = 0.337). However, when including Ni within the model, elevated blood pressure predicted clinically significant nocturia with noted statistical significance (OR 2.459, 95% CI 1.083 – 5.584, p = 0.032). Sub-group analysis on 113 black patients (25 having 0 or 1 nightly void on bladder diary and 88 found to have ≥ 2 nightly voids) was subsequently performed. Median age was 67.0 (62.5, 74.0) and amongst this cohort on multivariate analysis without including Ni as a covariate, elevated blood pressure was predictive of clinically significant nocturia but did not reach statistical significance (OR 2.297, 95% CI 0.882 – 5.980, p = 0.089). However, when including Ni within the model, elevated blood pressure predicted clinically significant nocturia to an even greater extent with noted statistical significance (OR 6.478, 95% CI 1.263 – 33.224, p = 0.025).