Different effects of morning and nocturnal hypertension on target organ damage in chronic kidney disease

Both morning hypertension (MH) and nocturnal hypertension (NH) are associated with severe target organ damage in patients with chronic kidney disease (CKD). However, the isolated or combined effects of MH and NH on target organ damage are less well-defined. A cross-sectional study was conducted among 2386 non-dialysis CKD patients with ambulatory blood pressure monitoring. The authors categorized patients into four groups based on the presence or absence of MH and NH. Multivariate logistic analyses were used to evaluate the correlation between hypertension subtypes and target organ damage, including left ventricular hypertrophy (LVH), abnormal carotid intima-media thickness (CIMT), low estimated glomerular filtration rate (eGFR), and albuminuria. The percentages of isolated MH, isolated NH, and combined MH and NH were 2.3%, 24.0%, and 49.3%, respectively. Compared to patients without MH and NH, isolated MH was only related to low eGFR (2.26 [95% confidence interval: 1.00-5.09]) and albuminuria (2.17 [95% CI: 1.03-4.54]). Meanwhile, combined MH and NH group compared to the group without MH and NH had a higher risk of LVH (2.87 [95% CI: 2.01-4.09]), abnormal CIMT (2.01 [95% CI: 1.47-2.75]), low eGFR (3.18 [95% CI: 2.23-4.54]), and albuminuria (1.79 [95% CI: 1.33-2.40]), even in patients without daytime hypertension. The risk of cardiovascular and renal damage was also observed in the isolated NH group. In conclusion, morning hypertension is associated with kidney dysfunction and has combined effects with nocturnal hypertension on cardiovascular damage in chronic kidney disease patients.