ORIGINAL
PAPER
Urinary Sodium Excretion and Ambulatory Blood Pressure Findings in Patients With Hypertension Baris Afsar, MD;1 Rengin Elsurer, MD;2 Alper Kirkpantur, MD;3 Mehmet Kanbay, MD4 From the Department of Nephrology, Konya Numune State Hospital, Konya, Turkey;1 Department of Nephrology, Selcuklu Faculty of Medicine, Selcuk University, Konya, Turkey;2 RFM Dialysis Center, Ankara, Turkey;3 and Division of Nephrology, Department of Medicine, Koc University School of Medicine, Istanbul, Turkey4
Use of ambulatory blood pressure (BP) monitoring (ABPM) allows for identification of dipping, nondipping, extreme dipping, and reverse dipping of BP. Using office BP and ABPM, hypertension subtypes can be identified: sustained normotension (SNT), white-coat hypertension, masked hypertension, and sustained hypertension. The comparison of hemodynamic parameters and salt intake has not been investigated among these patient groups. Office BP, ABPM, augmentation index (AIx), pulse wave velocity (PWV), cardiac output (CO), and total peripheral resistance (TPR) were
automatically measured. Estimation of salt intake was assessed by 24-hour urinary sodium excretion. Urinary sodium excretion was not different among groups. AIx, PWV, CO, and TPR were lowest in patients with SNT. CO was lowest while AIx adjusted for a heart rate of 75 beats per minute, PWV, and TPR were highest in the extreme dipper group. No relationship was detected between hypertension subtypes and urinary sodium excretion. J Clin Hypertens (Greenwich). 2015;17:200–206. ª 2015 Wiley Periodicals, Inc.
Use of ambulatory blood pressure (BP) monitoring (ABPM) allows for identification of four different patterns of the nocturnal BP profile (ie, normal dipping, nondipping, extreme dipping, and reverse dipping). These different BP patterns are associated with different rates of target organ damage and clinical outcome.1,2 At the same time, by using office (clinical) BP measurements and ABPM, another four group of patients are identifiable: those with (a) sustained normotension (SNT; normal BP in the office and on ABPM); (2) white-coat hypertension (WCHT; higher clinical BP but normal ABPM values); (3) masked hypertension (MHT; normal clinical BPs but higher ABPM values); and (4) sustained hypertension (SHT; both higher clinical and ABPM values).3 It has been suggested that salt intake is one of the most pivotal environmental factors in the pathogenesis of hypertension. Increased salt intake has been shown to change arterial wall structure and function.4 Therefore, increased sodium intake may result in adverse remodeling of the central and peripheral arterial vasculature that underlies both brachial and central pressure augmentation. Indeed, increased salt intake was associated with arterial stiffness.5–7 Some studies have also suggested that dipping status is linked to arterial stiffness and salt intake.8–10 The aims of the current study were: To compare salt intake measured by 24-hour urinary sodium excretion among dippers, extreme dippers,
nondippers, and reverse dippers and patients with SNT, WCHT, MHT, and SHT; To study the relationship between SNT, WHT, MHT, and SHT and dipping patterns; To compare pulse wave velocity (PWV), augmentation index (AIx), cardiac output (CO), and total peripheral resistance (TPR) among dippers, extreme dippers, nondippers, and reverse dippers and among patients with SNT, WCHT, MHT, and SHT by specifically adjusting for salt intake.
Address for correspondence: Baris Afsar, MD, Department of Nephrology, Konya Numune State Hospital, Ferhuniye Mah. Hastane Cad., 42690, Konya, Turkey E-mail: [email protected] Manuscript received: August 28, 2014; revised: November 5, 2014; accepted: November 9, 2014 DOI: 10.1111/jch.12464
200
The Journal of Clinical Hypertension
Vol 17 | No 3 | March 2015
MATERIALS AND METHODS The study had a cross-sectional design. The participants of this study were from the nephrology outpatient clinic of Selcuk University School of Medicine. The study was in accordance with the declaration of Helsinki, and informed consent was obtained from all patients before enrollment. The Selcuk University ethics committee approved the study with the approval number of 130-47. All patients with essential hypertension attending the nephrology outpatient clinic willing to participate were included. The exclusion criteria were as follows: patients with secondary hypertension, type 1 diabetes, rhythm and conduction problems, recent history (in past 6 months) of acute coronary syndrome, recent history of stroke, liver disease, obstructive sleep apnea, symptomatic heart failure, urinary tract infection, neurologic disorders, pulmonary and autoimmune diseases, refusal to participate, and night-shift workers. The demographic characteristics and medications were collected during anamnesis procedure. Twentyfour–hour urine specimens were collected to determine creatinine clearance, albumin and protein excretion, and urinary sodium excretion. Urine collection was assessed by predetermined standards.11
Sodium, Hemodynamics, and Blood Pressure | Afsar et al.
Office BP Measurement Office BP measurements were recorded by Omron MZ model (Omron Health Care, Mukou City, Kyoto, Japan) sphygmomanometer. BPs were measured according to European Society of Hypertension guidelines.12 Ambulatory BP Measurement Ambulatory BP measurement was performed by MobilO-Graph Arteriograph (I.E.M. GmbH, Stolberg, Germany) device, which has been validated.13 The device was set to obtain BP readings at 30-minute intervals during the day (7 AM–10 PM) and at 60-minute intervals during the night (10 PM–7 AM). Each ABPM dataset was first automatically scanned to remove artifactual readings according to preselected editing criteria. Each ABPM dataset was first automatically scanned to remove artifactual readings according to preselected editing criteria. Data were edited by omitting all readings of zero, all heart rate readings 170 mm Hg, systolic BP (SBP) readings >270 mm Hg and
PAPER
Urinary Sodium Excretion and Ambulatory Blood Pressure Findings in Patients With Hypertension Baris Afsar, MD;1 Rengin Elsurer, MD;2 Alper Kirkpantur, MD;3 Mehmet Kanbay, MD4 From the Department of Nephrology, Konya Numune State Hospital, Konya, Turkey;1 Department of Nephrology, Selcuklu Faculty of Medicine, Selcuk University, Konya, Turkey;2 RFM Dialysis Center, Ankara, Turkey;3 and Division of Nephrology, Department of Medicine, Koc University School of Medicine, Istanbul, Turkey4
Use of ambulatory blood pressure (BP) monitoring (ABPM) allows for identification of dipping, nondipping, extreme dipping, and reverse dipping of BP. Using office BP and ABPM, hypertension subtypes can be identified: sustained normotension (SNT), white-coat hypertension, masked hypertension, and sustained hypertension. The comparison of hemodynamic parameters and salt intake has not been investigated among these patient groups. Office BP, ABPM, augmentation index (AIx), pulse wave velocity (PWV), cardiac output (CO), and total peripheral resistance (TPR) were
automatically measured. Estimation of salt intake was assessed by 24-hour urinary sodium excretion. Urinary sodium excretion was not different among groups. AIx, PWV, CO, and TPR were lowest in patients with SNT. CO was lowest while AIx adjusted for a heart rate of 75 beats per minute, PWV, and TPR were highest in the extreme dipper group. No relationship was detected between hypertension subtypes and urinary sodium excretion. J Clin Hypertens (Greenwich). 2015;17:200–206. ª 2015 Wiley Periodicals, Inc.
Use of ambulatory blood pressure (BP) monitoring (ABPM) allows for identification of four different patterns of the nocturnal BP profile (ie, normal dipping, nondipping, extreme dipping, and reverse dipping). These different BP patterns are associated with different rates of target organ damage and clinical outcome.1,2 At the same time, by using office (clinical) BP measurements and ABPM, another four group of patients are identifiable: those with (a) sustained normotension (SNT; normal BP in the office and on ABPM); (2) white-coat hypertension (WCHT; higher clinical BP but normal ABPM values); (3) masked hypertension (MHT; normal clinical BPs but higher ABPM values); and (4) sustained hypertension (SHT; both higher clinical and ABPM values).3 It has been suggested that salt intake is one of the most pivotal environmental factors in the pathogenesis of hypertension. Increased salt intake has been shown to change arterial wall structure and function.4 Therefore, increased sodium intake may result in adverse remodeling of the central and peripheral arterial vasculature that underlies both brachial and central pressure augmentation. Indeed, increased salt intake was associated with arterial stiffness.5–7 Some studies have also suggested that dipping status is linked to arterial stiffness and salt intake.8–10 The aims of the current study were: To compare salt intake measured by 24-hour urinary sodium excretion among dippers, extreme dippers,
nondippers, and reverse dippers and patients with SNT, WCHT, MHT, and SHT; To study the relationship between SNT, WHT, MHT, and SHT and dipping patterns; To compare pulse wave velocity (PWV), augmentation index (AIx), cardiac output (CO), and total peripheral resistance (TPR) among dippers, extreme dippers, nondippers, and reverse dippers and among patients with SNT, WCHT, MHT, and SHT by specifically adjusting for salt intake.
Address for correspondence: Baris Afsar, MD, Department of Nephrology, Konya Numune State Hospital, Ferhuniye Mah. Hastane Cad., 42690, Konya, Turkey E-mail: [email protected] Manuscript received: August 28, 2014; revised: November 5, 2014; accepted: November 9, 2014 DOI: 10.1111/jch.12464
200
The Journal of Clinical Hypertension
Vol 17 | No 3 | March 2015
MATERIALS AND METHODS The study had a cross-sectional design. The participants of this study were from the nephrology outpatient clinic of Selcuk University School of Medicine. The study was in accordance with the declaration of Helsinki, and informed consent was obtained from all patients before enrollment. The Selcuk University ethics committee approved the study with the approval number of 130-47. All patients with essential hypertension attending the nephrology outpatient clinic willing to participate were included. The exclusion criteria were as follows: patients with secondary hypertension, type 1 diabetes, rhythm and conduction problems, recent history (in past 6 months) of acute coronary syndrome, recent history of stroke, liver disease, obstructive sleep apnea, symptomatic heart failure, urinary tract infection, neurologic disorders, pulmonary and autoimmune diseases, refusal to participate, and night-shift workers. The demographic characteristics and medications were collected during anamnesis procedure. Twentyfour–hour urine specimens were collected to determine creatinine clearance, albumin and protein excretion, and urinary sodium excretion. Urine collection was assessed by predetermined standards.11
Sodium, Hemodynamics, and Blood Pressure | Afsar et al.
Office BP Measurement Office BP measurements were recorded by Omron MZ model (Omron Health Care, Mukou City, Kyoto, Japan) sphygmomanometer. BPs were measured according to European Society of Hypertension guidelines.12 Ambulatory BP Measurement Ambulatory BP measurement was performed by MobilO-Graph Arteriograph (I.E.M. GmbH, Stolberg, Germany) device, which has been validated.13 The device was set to obtain BP readings at 30-minute intervals during the day (7 AM–10 PM) and at 60-minute intervals during the night (10 PM–7 AM). Each ABPM dataset was first automatically scanned to remove artifactual readings according to preselected editing criteria. Each ABPM dataset was first automatically scanned to remove artifactual readings according to preselected editing criteria. Data were edited by omitting all readings of zero, all heart rate readings 170 mm Hg, systolic BP (SBP) readings >270 mm Hg and
![[Relationship between urinary sodium and potassium excretion and blood pressure].](/assets/img/hold.png)
