Simple predictive score for nocturnal hypertension and masked nocturnal hypertension using home blood pressure monitoring in clinical practice

Objective: The decision whether to measure night-time blood pressure (BP) is challenging as these values cannot be easily evaluated because of problems with measurement devices and related stress. Using the nationwide, practice-based Japan Morning Surge-Home BP Nocturnal BP study data, we developed a simple predictive score that physicians can use to diagnose nocturnal hypertension. Methods: We divided 2765 outpatients (mean age 63 years; hypertensive patients 92%) with cardiovascular risks who underwent morning, evening, and night-time home BP (HBP) measurements (0200, 0300, and 0400 h) into a calibration group (n = 2212) and validation group (n = 553). We used logistic-regression models in the calibration group to identify the predictive score for nocturnal hypertension (night-time HBP >= 120/70 mmHg) and then evaluated the score's predictive ability in the validation group. Results: In the logistic-regression model, male sex, increased BMI) (>= 25 kg/m(2)), diabetes, elevated urine-albumin creatinine ratio (UACR) (>= 30 mg/g Cr), elevated office BP (>= 140/90 mmHg) and home (average of morning and evening) BP (>= 135/85 mmHg) had positive relationships with nocturnal hypertension. The predictive scores for nocturnal hypertension were 1 point (male, BMI, and UACR); 2 points (diabetes); 3 points (office BP >= 140/90 mmHg); 6 points (home BP >= 135/85 mmHg); total 14 points. Over 75% of the nocturnal hypertension cases in the validation group showed at least 10 points [AUC 0.691, 95% CI (0.647-0.735)]. We also developed a score for masked nocturnal hypertension, that is, nocturnal hypertension despite controlled daytime HBP. Conclusion: We developed a simple predictive score for nocturnal hypertension that can be used in clinical settings and for diagnoses.

Automated summary

This study developed a simple predictive score for diagnosing nocturnal hypertension using nationwide data. The score takes into account factors such as gender, BMI, diabetes, and blood pressure levels to predict the presence of nocturnal hypertension. It can be used in clinical settings for diagnosing patients.