Fluid restriction versus no active treatment in chronic SIAD
| ISRCTN | ISRCTN34822127 |
|---|---|
| DOI | https://doi.org/10.1186/ISRCTN34822127 |
| Secondary identifying numbers | 1 |
- Submission date
- 03/04/2018
- Registration date
- 27/04/2018
- Last edited
- 05/08/2021
- Recruitment status
- No longer recruiting
- Overall study status
- Completed
- Condition category
- Nutritional, Metabolic, Endocrine
Plain English summary of protocol
Background and study aims
Up to 30% of patients admitted to hospital are found to have low sodium levels in their blood – a condition called hyponatremia. The most common cause is the syndrome of inappropriate antidiuresis (SIAD). SIAD occurs when levels of a hormone called vasopressin are higher than they should be. Causes include lung disease, brain injuries and medications. In some cases, no cause for SIAD is found. Many patients with low sodium due to SIAD feel they have no symptoms, especially if the problem is longstanding. However, low plasma sodium can cause subtle problems with balance and bone health.
At present, the treatment options for SIAD are not ideal and often ineffective. The recommended treatment for SIAD is to limit the amount of fluid a person takes per day – this is called fluid restriction. This can prove difficult for some patients, especially in the long-term and there is no reliable evidence from research studies to support its use. Up to one in five patients with low plasma sodium do not receive treatment in hospital aimed at their sodium. Often, these patients do as well as those who were treated with fluid restriction.
This study aims to determine if fluid restriction is any better than doing nothing in terms of correcting plasma sodium.
Who can participate?
Adults aged over 18 years with chronic hyponatraemia
What does the study involve?
Participants are randomly allocated to either no treatment or fluid restriction for a period of 30 days. Participants self-report their fluid intake, and are met 5 - 6 times during this period, during which time they have blood samples taken for sodium measurement. On the first and final visit, they are asked to complete a questionnaire and to walk across a gait analysis mat.
What are the possible benefits and risks of participating?
There are no direct benefits for participants taking part in the study.
Participants may be at risk of their sodium level falling further and developing symptoms such as headache or nausea. For this reason, participants are monitored regularly – after three days, one week and then two weeks. If sodium level falls and/or the participants develop symptoms they are treated with the appropriate treatment regardless of the study.
Where is the study run from?
Beaumont Hospital (Ireland)
When is the study starting and how long is it expected to run for?
January 2018 to October 2020 (updated 04/09/2019, previously: January 2020)
Who is funding the study?
Beaumont Hospital Endocrinology Research Fund (Ireland)
Who is the main contact?
Prof Chris Thompson (Scientific)
Contact information
Scientific
Academic Department of Endocrinology / RCSI
Beaumont Hospital
Dublin
9
Ireland
Study information
| Study design | Prospective unblinded randomised controlled trial |
|---|---|
| Primary study design | Interventional |
| Secondary study design | Randomised controlled trial |
| Study setting(s) | Hospital |
| Study type | Treatment |
| Participant information sheet | Not available in web format |
| Scientific title | A prospective randomised controlled trial comparing the effects of fluid restriction with no active hyponatremia treatment on rate of change of plasma sodium, and markers of hyponatraemia related morbidity, in patients with chronic hyponatremia due to the syndrome of inappropriate antidiuresis. |
| Study objectives | No active hyponatraemia treatment is non-inferior to fluid restriction in correcting hyponatraemia in chronic SIAD |
| Ethics approval(s) | Beaumont Hospital Research Ethics Committee, 26/03/2018, ref: REC REF 18/04 |
| Health condition(s) or problem(s) studied | Chronic asymptomatic syndrome of inappropriate antidiuresis (SIAD) |
| Intervention | Once informed consent is acquired, participants are randomised to either fluid restriction or no active hyponatraemia treatment using a computer generated randomisation schedule using permutated blocks of four. Participants randomised to fluid restriction are instructed to limit total fluid intake to 1 litre per 24 hours. Those randomised to no active treatment should continue to drink as usual. Fluid intake is self-reported. The intervention period is 30 days. Participants are assessed at day 1, 4, 11, 18 and 30, including medication check, documenting fluid intake records and blood sampling. |
| Intervention type | Behavioural |
| Primary outcome measure | Plasma sodium is measured from a blood sample at baseline, 4 days and 30 days |
| Secondary outcome measures | 1. Percentage of patients achieving a rise in plasma sodium > 5 mmol/L is assessed from a blood sample at days 4 and 30. 2. Percentage of patients achieving a plasma sodium > 130 mmol/L is assessed from a blood sample at days 4 and 30. 3. Length of hospital stay (if applicable) is assessed using the hospital record system at day 30. 4. Plasma sodium at time of hospital discharge (if applicable) is assessed using the hospital laboratory record system. 5. Urinary sodium, potassium and osmolality in those with treatment failure versus those who achieve above treatment thresholds is assessed from urine sample taken at baseline. 6. Mental and physical well-being is assessed using SF12 questionnaire at baseline and after 1 month. 7. Balance is assessed using the FootScan analysis mat at baseline and after 1 month. |
| Overall study start date | 01/01/2018 |
| Completion date | 31/01/2020 |
Eligibility
| Participant type(s) | Patient |
|---|---|
| Age group | Adult |
| Lower age limit | 18 Years |
| Sex | Both |
| Target number of participants | 56 |
| Total final enrolment | 46 |
| Key inclusion criteria | 1. Age > 18 years 2. Chronic hyponatraemia with plasma sodium 120 - 130 mmol/L 3. Euvolemia and biochemical confirmation of SIAD. |
| Key exclusion criteria | 1. Symptomatic hyponatraemia 2. Plasma sodium < 120 mmol/L 3. An underlying cause for hyponatraemia is recognised which is temporary or rapidly reversible with treatment of the underlying condition or removal of the causative medication 4. Hypo- or hyper-volemia 5. Diuretic therapy 6. Uncontrolled hyperglycaemia (blood glucose > 16.6 mmol/L) 7. Pregnancy |
| Date of first enrolment | 01/05/2018 |
| Date of final enrolment | 31/01/2020 |
Locations
Countries of recruitment
- Ireland
Study participating centre
Dublin
9
Ireland
Sponsor information
Hospital/treatment centre
Academic Department of Endocrinology / RCSI
Beaumont Hospital
Dublin
9
Ireland
"ROR" |
https://ror.org/043mzjj67 |
|---|
Funders
Funder type
Hospital/treatment centre
No information available
Results and Publications
| Intention to publish date | 01/01/2021 |
|---|---|
| Individual participant data (IPD) Intention to share | Yes |
| IPD sharing plan summary | Available on request |
| Publication and dissemination plan | Plans to publish in peer-reviewed journal. |
| IPD sharing plan | Participant level data generated in this study will be available on request from Professor Chris Thompson (principal investigator). Data will be coded, and stored on the hospital secure electronic database. |
Study outputs
| Output type | Details | Date created | Date added | Peer reviewed? | Patient-facing? |
|---|---|---|---|---|---|
| Results article | results | 01/12/2020 | 05/08/2021 | Yes | No |
Editorial Notes
05/08/2021: The following changes have been made:
1. Publication reference added.
2. The total final enrolment number has been added from the reference.
04/09/2019: The following changes were made to the trial record:
1. The recruitment end date was changed from 01/07/2020 to 31/01/2020.
2. The overall end date was changed from 01/10/2020 to 31/01/2020.
04/09/2019: The following changes were made to the trial record:
1. The recruitment end date was changed from 01/05/2019 to 01/07/2020.
2. The overall end date was changed from 01/01/2020 to 01/10/2020.
3. The intention to publish date was changed from 01/01/2020 to 01/01/2021.
4. The plain English summary was updated to reflect these changes.
