High Prevalence of Isolated Nocturnal Hypertension in Chinese Patients With Chronic Kidney Disease

BACKGROUND Isolated nocturnal hypertension (INH) has been studied among the general population and hypertensive patients. However, little insight is available on the prevalence of INH and its role in target-organ damage among patients with chronic kidney disease (CKD). METHODS AND RESULTS We recruited 1282 CKD patients admitted to our hospital division. Patients were divided into 4 groups: INH; isolated daytime hypertension; day-night sustained; and ambulatory normotension. Multiple linear regression analyses were used to evaluate the correlation between INH and renal/cardiovascular parameters. A total of 262 (20.44%) CKD patients had isolated nocturnal hypertension and 651 (50.78%) had day-night sustained hypertension, whereas only 350 (27.30%) patients showed normotension and 19 (1.48%) had isolated daytime hypertension. Multivariate logistic regression analysis showed that INH was associated mainly with age, estimated glomerular filtration rate, clinic diastolic blood pressure, and that INH was determined only by age, estimated glomerular filtration rate, and clinic diastolic blood pressure. The prevalence of impaired renal function, left ventricular hypertrophy, and carotid intima-media thickness in patients with INH were higher than in normotensive patients (P<0.05), whereas impaired renal function and left ventricular hypertrophy in these patients were lower than patients in the day-night sustained hypertension group (P<0.05). INH was correlated with estimated glomerular filtration rate, left ventricular mass index, and carotid intima-media thickness according to multiple linear regression analyses. CONCLUSIONS The prevalence of INH in CKD patients was high, and INH was correlated with target-organ damage in CKD patients.