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

Abstract

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.

Keywords: ambulatory blood pressure monitoring; chronic kidney disease; morning hypertension; nocturnal hypertension; target organ damage.

FIGURE 1

Comparison of target organ damages in four blood pressure groups. LVH, left ventricular hypertrophy; CIMT, carotid intima‐media thickness; eGFR, estimated glomerular filtration rate; TOD, target organ damage; M+, with morning hypertension; M−, without morning hypertension; N+, with nocturnal hypertension; N−, without nocturnal hypertension

FIGURE 2

Multivariable logistic regression analysis for blood pressure types and target organ damage. Unadjusted model only contains blood pressure types. Additional adjustment variables for LVH include age, gender, alcohol intake, diabetes mellitus, cardiovascular disease history, antihypertensive drugs, hemoglobin, serum albumin, uric acid, homocysteine, serum fasting glucose, cholesterol, HDL‐C, LDL‐C, serum phosphate, iPTH, and eGFR; additional adjustment variables for abnormal CIMT include age, gender, BMI, current smoking, diabetes mellitus, cardiovascular disease history, antihypertensive drugs, statin, hemoglobin, serum albumin, uric acid, homocysteine, serum fasting glucose, and HDL‐C, iPTH, eGFR; additional adjustment variables for low eGFR include age, gender, current smoking, diabetes mellitus, cardiovascular disease history, antihypertensive drugs, hemoglobin, uric acid, homocysteine, cholesterol, HDL‐C, LDL‐C, serum phosphate, and iPTH; and additional adjustment variables for albuminuria include age, gender, alcohol intake, diabetes mellitus, cardiovascular disease history, antihypertensive drugs, statin, hemoglobin, serum albumin, homocysteine, uric acid, cholesterol, HDL‐C, LDL‐C, serum phosphate, iPTH, and eGFR. BMI, body mass index; CIMT, carotid intima‐media thickness; eGFR, estimated glomerular filtration rate; HDL‐C, high‐density lipoprotein cholesterol; iPTH, intact parathyroid hormone; LDL‐C, low‐density lipoprotein cholesterol; LVH, left ventricular hypertrophy; M−, without morning hypertension; M+, with morning hypertension; N−, without nocturnal hypertension; N+, with nocturnal hypertension