Clinical Trial Details
— Status: Active, not recruiting
Administrative data
| NCT number |
NCT03002415 |
| Other study ID # |
160153 |
| Secondary ID |
|
| Status |
Active, not recruiting |
| Phase |
N/A
|
| First received |
|
| Last updated |
|
| Start date |
March 1, 2017 |
| Est. completion date |
December 2021 |
Study information
| Verified date |
October 2021 |
| Source |
Hospital de Clinicas de Porto Alegre |
| Contact |
n/a |
| Is FDA regulated |
No |
| Health authority |
|
| Study type |
Interventional
|
Clinical Trial Summary
Acute dehydration in the elderly is a well-known clinical condition, although situations that
lead to chronic dehydration in the elderly may be quite frequent, but they are poorly
studied. Metabolic changes in body water homeostasis can influence and provide chronic
dehydration status as reduced sensitivity to thirst, antidiuretic hormone and renal inability
to concentrate urine and the presence of chronic diseases and the use of polypharmacy may
also predispose states of chronic dehydration. Due to these facts, a study to detect the
existence of chronic dehydration states in a population of elderly people is highly
justifiable. In addition, understanding whether increased water intake, improving chronic
dehydration, may improve renal function in this population seems to be of great value, since
it is a simple and inexpensive intervention and, if confirmed, it can be taken to
institutions, by family members and health promoters who care for and cohabit with elderly
individuals.
Our main objective is to evaluate the effect of stimulated and calculated water intake (per
kg of patient weight) on the state of hydration and renal function in a population of elderly
individuals. It is also within the scope of this project to evaluate the presence of chronic
dehydration in elderly patients as well as in a subgroup of diabetic patients, and to compare
different methods of evaluation of renal function. Design: Clinical trial Randomized for the
main objective and cross-sectional study for secondary objectives.
The principal hypothesis is that guided water intake improve renal function in elderly
patients.
Description:
Intervention:
Verbal and written guidelines will be given for the patient to ingest the daily volume of
water calculated by the weight (30 ml / kg / day) for 14 days. Patients will receive an
acrylic glass with a mark in 200 ml and will be instructed to take the number of glasses a
day corresponding to the calculated volume (30 ml / kg). Patients will also receive a leaflet
indicating how many glasses of water they will need to take. They will also be instructed to
mark with an "X" the number of glasses of water that they actually drank daily during the
fourteen days of intervention.
Measurements tools (applied on the first and second visits)
- Laboratory tests: serum and urinary osmolality, sodium, urea and serum creatinine. To
evaluate the effect of hydration on the glycemic control of diabetic patients, the
measurement of fasting glycaemia and glycated hemoglobin (enzymatic method and HCLP)
will also be performed. These dosages will be performed at the HCPA Clinical Pathology
Laboratory.
- Non-invasive test: electrical bioimpedance (BIA) InBody 370® will be used to evaluate
the amount of free water, since it is simple, low cost and easy to perform in the
outpatient clinics of elderly patients.
- Nutritional assessment: the MAN questionnaire (Mini nutritional assessment) will be
applied to patients selected for the study at the first and second visits. Since a valid
questionnaire to evaluate only water intake was not found, the MAN questionnaire was
chosen because it contains questions related to water intake and because it is easy and
quick to apply.
- MiniMental: The MiniMental cognitive function test will be applied on the first visit
and after the observation period (second visit). The questionnaire is valid for the
screening of cognitive disorders and it is a simple and quick method to evaluate the
mental abilities of the patients under study.
- Food record: these are sheets with space designated for filling with food and liquids
and quantities consumed throughout the day. Patients are advised to make a four-day food
diary out of the 14 days.
Renal function will be assessed by estimation formulas (as recommended by NKF and KDIGO) that
use serum creatinine (CKD-EPI, MDRD and BIS2) and formulas that use cystatin C (CKD- EPI-cys
and BIS 1).
The assessment of GFR by 51Cr-EDTA will be performed in a subgroup of 15 patients from each
arm of the study in a parallel manner before and after the intervention using the 51Cr-EDTA
intravenous single injection technique at a dose of 150μCi with blood samples taken at 2, 3
and 4 hours later. Samples will be centrifuged and 2 ml of plasma will be pipetted in
duplicate for gamma counter counting. An exponential equation evaluates the plasma decay of
51 Cr-EDTA, providing the value of GFR .
Serum creatinine will be determined by the calibrated Jaffe method (Roche), traceable to
isotopic dilution mass spectrometry (ID-MS), with kinetic reading to minimize interference by
bilirubin. The dosage of cystatin C will be performed by the immunoturbidimetry method
(Roche). The coefficients of intra and interassay variation are 2.2% and 5.3%, respectively.
