Effects of age on hypertensive status in patients with chronic kidney disease.
OBJECTIVE
To evaluate effect of age on hypertensive status in chronic kidney disease (CKD).


METHODS
We studied 459 prevalent CKD patients (stages 2-5, no dialysis), grouped by age (< 55, 55-64, 65-74, >or= 75 years), undergoing clinical blood pressure (CBP) and ambulatory blood pressure (ABP) measurement.


RESULTS
Prevalence of diabetes, left ventricular hypertrophy and previous cardiovascular disease progressively increased with aging; glomerular filtration rate (GFR) and hemoglobin decreased. Achievement of CBP target decreased from 16% in patients < 55 years to 6% in those >or= 75 years (P = 0.023). ABP 24-h systolic rose while diastolic decreased, with a consequent pulse pressure increase from 45 +/- 8 to 65 +/- 14 mmHg (P < 0.0001). Age, proteinuria, diabetes, cardiovascular disease and anemia but not GFR predicted higher 24-h pulse pressure. CBP overestimated systolic/diastolic daytime ABP by 14 +/- 18/7 +/- 11 mmHg on average, a greater difference in older than younger groups (P < 0.005). Conversely, CBP night-time ABP difference did not vary among groups (24 +/- 20/16 +/- 11 mmHg). These age-dependent differences determined a rising prevalence of white-coat hypertension (from 19 to 40%, P = 0.001) and night/day ratio of at least 0.9 (from 43 to 66%, P = 0.0004). Age, diabetes, left ventricular hypertrophy and anemia but not GFR predicted nondipping status. Among the oldest patients, 13% had diastolic CBP below 70 mmHg, with 48% below the corresponding values of daytime (< 69 mmHg) or night-time ABP (< 60 mmHg).


CONCLUSIONS
In CKD, prevalence of white-coat hypertension, nondipping status and potentially dangerous low diastolic ABP increases with aging. This suggests wider use of ABP monitoring in older patients and need for trials addressing identification of an age-specific blood pressure target.
Minutolo
Roberto
R
Department of Nephrology, Second University of Naples, Italy. roberto.minutolo@unina2.it
Borrelli
Silvio
S
Chiodini
Paolo
P
Scigliano
Raffaele
R
Bellizzi
Vincenzo
V
Cianciaruso
Bruno
B
Nappi
Felice
F
Zamboli
Pasquale
P
Catapano
Fausta
F
Conte
Giuseppe
G
De Nicola
Luca
L
D000328:Adult; D000367:Age Factors; D000368:Aged; D001794:Blood Pressure; D018660:Blood Pressure Monitoring, Ambulatory; D002908:Chronic Disease; D003430:Cross-Sectional Studies; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D006973:Hypertension / Q000503:physiopathology*; D007674:Kidney Diseases / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies