Ignite Creation Date:
2024-05-05 @ 11:07 AM
Last Modification Date:
2024-10-26 @ 9:04 AM
Study NCT ID:
NCT00005204
Status:
COMPLETED
Last Update Posted:
2016-03-16
First Post:
2000-05-25
Brief Title:
Blood Pressure and Diurnal Variation in Sodium Potassium and Water Excretion
Sponsor:
National Heart Lung and Blood Institute NHLBI
Organization:
National Heart Lung and Blood Institute NHLBI
Study Overview
Official Title:
None
Status:
COMPLETED
Status Verified Date:
2001-11
Last Known Status:
None
Delayed Posting:
No
If Stopped, Why?:
Not Stopped
Has Expanded Access:
False
If Expanded Access, NCT#:
N/A
Has Expanded Access, NCT# Status:
N/A
Acronym:
None
Brief Summary:
To determine if hypertensives and normotensives of similar ages had on average different ratios of 24-hour to overnight excretion of sodium potassium and water Also to determine the number of 24-hour collections needed to characterize individuals with respect to the ratios of 24-hour to overnight excretion and to determine if the ratios of 24-hour to overnight excretion vary by age and other factors related to blood pressure
Detailed Description:
BACKGROUND
For decades excess sodium intake has been implicated in the etiopathogenesis of high blood pressure Data from epidemiological clinical and animal experimental studies all suggest a direct casual association between excess salt intake and hypertension Several investigators suggest that hypertension is the result of an inability of the kidney to excrete salt and water normally It is hypothesized that the development of chronic blood pressure elevation results from the kidneys need to increase urine volume and sodium excretion -- in the presence of habitual high sodium intake -- in order to maintain homeostasis of the extracellular fluid volume
Diurnal variations in excretion of sodium chloride potassium and water have been observed in several studies Water and electrolyte excretion in normal individuals generally reaches a maximum sometime around midday with a minimum toward the end of the sleep period These studies suggest that the daytime excretion rate exceeds the nighttime rate by 50 to 100 percent Overnight urine collections have been used in many studies since they are easier to obtain but they do not provide a direct estimate of the actual intake of sodium or potassium In order to estimate actual intake overnight values must be corrected to 24-hour values that is by multiplying the overnight values by previously determined ratios of 24-hour to overnight excretions Preliminary studies by this group of investigators in hypertensives were the first which computed 24-hour to overnight ratios for excretion of sodium potassium and creatinine in a definite way This study in hypertensives showed a reversal of the diurnal cycle of sodium excretion What is not clear in this study and others is whether the reversal is associated with hypertension or reflects decreased renal function with age or whether deterioration of renal function is due to the kidney readjusting its output of salt and water to maintain homeostasis in the face of both an excess sodium intake and a highly variable day to day intake In addition it may be that an abnormal diurnal pattern of sodium excretion may indicate that one is at risk of development of hypertension
DESIGN NARRATIVE
Each participant provided three 24-hour urine collections divided into daytime and overnight specimens for the assessment of sodium potassium creatinine and water excretion Four blood pressure measurements were made Height and weight were measured Information was collected on demographic variables alcohol intake history and treatment of blood pressure medication use family history of high blood pressure cigarette use and changes in dietary habits Analysis of variance was the primary method of data analysis
The study completion date listed in this record was obtained from the End Date entered in the Protocol Registration and Results System PRS record
For decades excess sodium intake has been implicated in the etiopathogenesis of high blood pressure Data from epidemiological clinical and animal experimental studies all suggest a direct casual association between excess salt intake and hypertension Several investigators suggest that hypertension is the result of an inability of the kidney to excrete salt and water normally It is hypothesized that the development of chronic blood pressure elevation results from the kidneys need to increase urine volume and sodium excretion -- in the presence of habitual high sodium intake -- in order to maintain homeostasis of the extracellular fluid volume
Diurnal variations in excretion of sodium chloride potassium and water have been observed in several studies Water and electrolyte excretion in normal individuals generally reaches a maximum sometime around midday with a minimum toward the end of the sleep period These studies suggest that the daytime excretion rate exceeds the nighttime rate by 50 to 100 percent Overnight urine collections have been used in many studies since they are easier to obtain but they do not provide a direct estimate of the actual intake of sodium or potassium In order to estimate actual intake overnight values must be corrected to 24-hour values that is by multiplying the overnight values by previously determined ratios of 24-hour to overnight excretions Preliminary studies by this group of investigators in hypertensives were the first which computed 24-hour to overnight ratios for excretion of sodium potassium and creatinine in a definite way This study in hypertensives showed a reversal of the diurnal cycle of sodium excretion What is not clear in this study and others is whether the reversal is associated with hypertension or reflects decreased renal function with age or whether deterioration of renal function is due to the kidney readjusting its output of salt and water to maintain homeostasis in the face of both an excess sodium intake and a highly variable day to day intake In addition it may be that an abnormal diurnal pattern of sodium excretion may indicate that one is at risk of development of hypertension
DESIGN NARRATIVE
Each participant provided three 24-hour urine collections divided into daytime and overnight specimens for the assessment of sodium potassium creatinine and water excretion Four blood pressure measurements were made Height and weight were measured Information was collected on demographic variables alcohol intake history and treatment of blood pressure medication use family history of high blood pressure cigarette use and changes in dietary habits Analysis of variance was the primary method of data analysis
The study completion date listed in this record was obtained from the End Date entered in the Protocol Registration and Results System PRS record
Study Oversight
Has Oversight DMC:
Is a FDA Regulated Drug?:
Is a FDA Regulated Device?:
Is an Unapproved Device?:
Is a PPSD?:
Is a US Export?:
Is an FDA AA801 Violation?:
Secondary IDs
| Secondary ID | Type | Domain | Link |
|---|---|---|---|
| R01HL038897 | NIH | None | httpsreporternihgovquickSearchR01HL038897 |