To Bathe or Not to Bathe
Study Details
Study Description
Brief Summary
Type 2 diabetes mellitus (T2DM) is characterised by chronic high blood sugar concentration (hyperglycaemia) and insulin resistance leading to a reduction in insulin sensitivity. These hyperglycaemic excursions can seriously impact metabolic, micro and macrovascular health. The total cost of the direct and indirect care of individuals with diabetes (~90% T2DM) in the UK (United Kingdom) is £23.7 billion, equating to ~20% of the annual national health service (NHS) budget, with this projected to become unsustainable. Low-cost interventions to improve glycaemic control in these individuals are therefore warranted. Current interventions include pharmaceuticals, exercise and calorie restrictive diets. Pharmaceutical interventions carry a high financial cost, while exercise and diet programmes have a low adherence rate in individuals with T2DM.
Heat therapy offers one potential low cost therapy. Immersion in a hot tub for 30 mins.day-1 for 10 days has been shown to reduce fasting plasma [glucose] and HbA1c in individuals with T2DM, which may be explained by acute (e.g. muscle) and chronic (e.g. reduced inflammatory status and increased heat shock proteins (HSP)) adaptations, although experimental evidence for these hypothesis are sparse. Other potential benefits include improved glycaemic control, insulin sensitivity, elevated resting metabolic rate and improved micro- and macrovascular function.
The aim of the present study is to determine whether acute hot water immersion can improve glucose tolerance in individuals with T2DM and whether it is more beneficial to undertake this before or after a OGTT (oral glucose tolerance test).
| Condition or Disease | Intervention/Treatment | Phase |
|---|---|---|
|
N/A |
Detailed Description
Visit 1 (consent, screening and familiarisation) During visit 1, participants will give their informed consent, followed by a health screening questionnaire. In addition to the health screening questionnaire, medical history and a blood sample will be collected and analysed for a full blood count, glycated haemoglobin (HbA1c), liver and kidney function. Finally, a resting electrocardiogram (ECG) will also be recorded and then examined for irregularities, where a clinical decision will be made on further participation to the study by consultants at QA (Queen Alexandra) hospital. Participants will then be shown the rest of the equipment and taken through the procedure for the next 3 visits and, if the participant is happy to continue the study, the next visit will be organised.
Visit 2, 3 and 4 Participants will arrive at the laboratory at ~9 am for conditions 1 and 2 and 8 am for condition 3. Prior to a 15 min resting period (supine) before any measures are taken participants will be asked to insert a rectal thermistor (participants will be given clear instructions using the investigator's SoPs (standard operating procedure)). Condition 1, 2 and 3 will be balanced and participants randomly allocated to begin the study in either visit 2, 3 or 4 using a blinded member of the team.
For all visits (see figure 2), participants will lie in a semi recumbent position in minimal clothing (bathing shorts and a t-shirt) for the entirety of the visit. Initially, participants will be cannulated (Versatus winged and ported IV cannula, Terumo, Japan) and blood samples drawn for analysis of osmolality (Lithium Heparin (LH) tubes BD (Becton, Dickinson and Company), USA) plasma [glucose] (Fluoride/Oxalate tubes, BD, USA), [insulin] (Ethylenediaminetetraacetic acid (EDTA) K2, BD, USA), and [eHSP70 (extracellular heat shock protein 70)] (EDTA K2, BD, USA) at baseline and every 30 min of each experimental visit. Following cannulation an 180 min OGTT (75g) (Rapilose OGTT solution, Penlan healthcare, Japan) will commence in a thermoneutral room (~ 23oC). A maximum of 18 mL of blood being drawn at each time point (max 126 mL per visit). To maintain the patency of the cannula and to reduce the risk of infection, after every sample is taken, 5 mL of saline will be flushed through the cannula. Then before every sample is taken, 2.5 mL of blood will be drawn out of the cannula to ensure any remaining saline will not interfere with the samples and data interpretation (additional 17.5mL per visit). During the OGTT, HR (heart rate) (via electrocardiogram) will be measured continuously, whilst blood pressure (M5-1, Omron, Japan), deep body temperature (rectal probe) and resting metabolic rate (indirect calorimetry) (Quark CPET (cardiopulmonary exercise test), Cosmed, Italy) will be assessed every 30 min.
Condition 2 will employ identical procedures to condition 1, except thirty minutes into the OGTT, the participant will be immersed into an immersion tank (~39oC) for 60 min. Water temperature will be manipulated as required to achieve and maintain a target Trec at 38.5 oC using water between 37.5 and 39oC, and then participants will be removed horizontally back into the thermoneutral room for the reminder of the OGTT. Participants will be towel dried and given a towelled robe to wear. Condition 3 will employ identical procedures to condition 2, with the exception that the heating via immersion will start as soon as the participant is instrumented (and following a 15 min rest period) and the OGTT will commence 30 min after the 60 min immersion time for a further 180 min (see figure 2 for a schematic).
Study Design
Arms and Interventions
| Arm | Intervention/Treatment |
|---|---|
| No Intervention: Control Participants will lie in a semi recumbent position in minimal clothing for the entirety of the visit. Initially, participants will be cannulated and blood samples drawn.every 30 min of each experimental visit. Following cannulation an 180 min OGTT (75g) will commence in a thermoneutral room (~ 23C). During the OGTT, HR will be measured continuously, whilst blood pressure, deep body temperature (rectal probe) and resting metabolic rate will be assessed every 30 min. |
|
| Experimental: Pre OGTT Condition 2 will employ identical procedures to condition 1, except thirty minutes into the OGTT, the participant will be immersed into an immersion tank (~39oC) for 60 min. Water temperature will be manipulated as required to achieve and maintain a target Trec at 38.5 oC using water between 37.5 and 39oC, and then participants will be removed horizontally back into the thermoneutral room for the reminder of the OGTT. Participants will be towel dried and given a towelled robe to wear. |
Diagnostic Test: Heating
Warm water immersion
Other Names:
|
| Experimental: Post OGTT Condition 3 will employ identical procedures to condition 2, with the exception that the heating via immersion will start as soon as the participant is instrumented (and following a 15 min rest period) and the OGTT will commence 30 min after the 60 min immersion time for a further 180 min. |
Diagnostic Test: Heating
Warm water immersion
Other Names:
|
Outcome Measures
Primary Outcome Measures
- Mean AUC (Area Under the Curve) Plasma [Glucose] [Visit 2, 3 and 4. 3 times in total, until study completion, approximately 8 weeks]
Does an acute bout of passive, warm water therapy reduce plasma [glucose]? Units for AUC are AU (arbitrary units) which have been derived from the trapezoidal method and have been published as such. Trapezoidal method: AUC = Δx ((y0/2)+y1+y2+y3+...+(yn/2)).
Secondary Outcome Measures
- Change in Plasma [Insulin] [Visit 2, 3 and 4. 3 times in total, until study completion, approximately 8 weeks]
Does plasma [insulin] reduce more if the passive, warm water therapy is conducted before or after the OGTT?
- Mean Insulin Sensitivity [Visit 2, 3 and 4. 3 times in total, until study completion, approximately 8 weeks]
Does insulin sensitivity increase following an acute bout of warm water therapy? Calculation of insulin sensitivity is measured in AU which have been derived from the Gutt method and have been published as such. Gutt insulin sensitivity = [75,000 + (G0-G120) × 0.19 × BW]/(120 × log [(I0 + I120)/2] × [(G0 + G120)/2]). Where G = plasma [glucose], I = plasma [insulin] and BW = body weight.
- Change in Fuel Utilisation [Visit 2, 3 and 4. 3 times in total, until study completion, approximately 8 weeks]
Does carbohydrate and fat (RER) utilisation alter during and following an acute bout of warm water therapy?
- Change in Cardiovascular Status [Visit 2, 3 and 4. 3 times in total, until study completion, approximately 8 weeks]
Does heart rate (variability) change during or after an acute bout of warm water therapy?
- Change in eHSP70 (Extracellular Heat Shock Protein 70) [Visit 2, 3 and 4. 3 times in total, until study completion, approximately 8 weeks]
Does eHSP increases during and following an acute bout of warm water therapy?
- Change in Inflammatory Status [Visit 2, 3 and 4. 3 times in total, until study completion, approximately 8 weeks]
Does inflammatory status (IL-6 & IL-10) change during or after an acute bout of warm water therapy?
Eligibility Criteria
Criteria
The participants must meet all of the following criteria to be considered eligible for the study:
-
Male or female (either post-menopausal or in the early-follicular phase (3-5 days after the onset of menstruation) of the menstrual cycle), aged 35 years or above.
-
Diagnosed with T2DM as defined by the WHO (World Health Organisation).
-
Participant is willing and able to give informed consent for participation in the study.
-
Participant is able to understand and fully cooperate with the study protocol.
Exclusion Criteria
The participant may not enter / be withdrawn from the study if any of the following apply:
-
Severe peripheral neuropathy (to the point to which they cannot sense temperature)
-
Uncontrolled hypertension (≥180 systolic / 100 diastolic mmHg)
-
Taking any medication which may interfere with data interpretation or safety
-
Who have had a myocardial infarction or cerebro-vascular event
-
Any cardiac abnormalities which restrict hard exercise
-
Current smokers or who have stopped within 3 months
-
Participant is unable to understand and/or fully cooperate with the study protocol
-
Any other serious medical condition which would interfere with data interpretation or safety will be excluded from participation.
-
Any skin conditions including ulcerations
Contacts and Locations
Locations
| Site | City | State | Country | Postal Code | |
|---|---|---|---|---|---|
| 1 | Department of Sport and Exercise Science | Portsmouth | Hampshire | United Kingdom | PO1 2ER |
Sponsors and Collaborators
- University of Portsmouth
- Portsmouth Hospitals NHS Trust
Investigators
None specified.Study Documents (Full-Text)
More Information
Publications
None provided.- 003AS
Study Results
Participant Flow
| Recruitment Details | 440 individuals were screened for eligibility (200 clinical letters, 40 from day events and 200 from local diabetes education group). 420 declined and 0 were excluded. Once participants were randomly allocated to arm sequence 5 withdrew before starting. Three in-between experimental visits. Twelve completed the study and data analysed. |
|---|---|
| Pre-assignment Detail | Participants were excluded from the study before assignment to groups if they did not pass screening criteria. Balanced randomisation of order in which individuals completed each arm (cross-over) was carried out. Therefore there was an equal number of individuals completing all combinations of arms. |
| Arm/Group Title | Control - Pre OGTT - Post OGTT | Control - Post OGTT - Pre OGTT | Pre OGTT - Control - Post OGTT | Pre OGTT - Post OGTT - Control | Post OGTT - Control - Pre OGTT | Post OGTT - Pre OGTT - Control |
|---|---|---|---|---|---|---|
| Arm/Group Description | Participants first underwent a 3 h OGTT (oral glucose tolerance test) with no passive heating. Then approximately a week later underwent a 1 h bout of passive heating ending 30 min before undertaking a 3 h OGTT. Then, approximately a week underwent a 1 h bout of passive heating 30 min into a 3 h OGTT. | Participants first underwent a 3 h OGTT with no passive heating. Then, approximately a week underwent a 1 h bout of passive heating 30 min into a 3 h OGTT. Then approximately a week later underwent a 1 h bout of passive heating ending 30 min before undertaking a 3 h OGTT. | Participants first underwent a 1 h bout of passive heating ending 30 min before undertaking a 3 h OGTT. Then, approximately a week later underwent a 3 h OGTT with no passive heating. Then, approximately a week underwent a 1 h bout of passive heating 30 min into a 3 h OGTT. | Participants first underwent a 1 h bout of passive heating ending 30 min before undertaking a 3 h OGTT. Then, approximately a week underwent a 1 h bout of passive heating 30 min into a 3 h OGTT. Then, approximately a week later underwent a 3 h OGTT with no passive heating. | Participants first underwent underwent a 1 h bout of passive heating 30 min into a 3 h OGTT. Then, approximately a week later underwent a 3 h OGTT with no passive heating. Then, approximately a week later underwent 1 h bout of passive heating ending 30 min before undertaking a 3 h OGTT. | Participants first underwent underwent a 1 h bout of passive heating 30 min into a 3 h OGTT. Then, approximately a week later underwent 1 h bout of passive heating ending 30 min before undertaking a 3 h OGTT. Then, approximately a week later underwent a 3 h OGTT with no passive heating. |
| Period Title: Overall Study | ||||||
| STARTED | 4 | 3 | 3 | 4 | 3 | 3 |
| COMPLETED | 2 | 2 | 2 | 2 | 2 | 2 |
| NOT COMPLETED | 2 | 1 | 1 | 2 | 1 | 1 |
Baseline Characteristics
| Arm/Group Title | Control - Pre OGTT - Post OGTT | Control - Post OGTT - Pre OGTT | Pre OGTT - Control - Post OGTT | Pre OGTT - Post OGTT - Control | Post OGTT - Control - Pre OGTT | Post OGTT - Pre OGTT - Control | Total |
|---|---|---|---|---|---|---|---|
| Arm/Group Description | Participants first underwent a 3 h OGTT with no passive heating. Then approximately a week later underwent a 1 h bout of passive heating ending 30 min before undertaking a 3 h OGTT. Then, approximately a week underwent a 1 h bout of passive heating 30 min into a 3 h OGTT. | Participants first underwent a 3 h OGTT with no passive heating. Then, approximately a week underwent a 1 h bout of passive heating 30 min into a 3 h OGTT. Then approximately a week later underwent a 1 h bout of passive heating ending 30 min before undertaking a 3 h OGTT. | Participants first underwent a 1 h bout of passive heating ending 30 min before undertaking a 3 h OGTT. Then, approximately a week later underwent a 3 h OGTT with no passive heating. Then, approximately a week underwent a 1 h bout of passive heating 30 min into a 3 h OGTT. | Participants first underwent a 1 h bout of passive heating ending 30 min before undertaking a 3 h OGTT. Then, approximately a week underwent a 1 h bout of passive heating 30 min into a 3 h OGTT. Then, approximately a week later underwent a 3 h OGTT with no passive heating. | Participants first underwent underwent a 1 h bout of passive heating 30 min into a 3 h OGTT. Then, approximately a week later underwent a 3 h OGTT with no passive heating. Then, approximately a week later underwent 1 h bout of passive heating ending 30 min before undertaking a 3 h OGTT. | Participants first underwent underwent a 1 h bout of passive heating 30 min into a 3 h OGTT. Then, approximately a week later underwent 1 h bout of passive heating ending 30 min before undertaking a 3 h OGTT. Then, approximately a week later underwent a 3 h OGTT with no passive heating. | Total of all reporting groups |
| Overall Participants | 4 | 3 | 3 | 4 | 3 | 3 | 20 |
| Age (Count of Participants) | |||||||
| <=18 years |
0
0%
|
0
0%
|
0
0%
|
0
0%
|
0
0%
|
0
0%
|
0
0%
|
| Between 18 and 65 years |
2
50%
|
1
33.3%
|
1
33.3%
|
2
50%
|
1
33.3%
|
2
66.7%
|
9
45%
|
| >=65 years |
2
50%
|
2
66.7%
|
2
66.7%
|
2
50%
|
2
66.7%
|
1
33.3%
|
11
55%
|
| Sex: Female, Male (Count of Participants) | |||||||
| Female |
1
25%
|
1
33.3%
|
1
33.3%
|
1
25%
|
0
0%
|
1
33.3%
|
5
25%
|
| Male |
3
75%
|
2
66.7%
|
2
66.7%
|
3
75%
|
3
100%
|
2
66.7%
|
15
75%
|
| Race and Ethnicity Not Collected (Count of Participants) | |||||||
| Count of Participants [Participants] |
0
0%
|
||||||
Outcome Measures
| Title | Mean AUC (Area Under the Curve) Plasma [Glucose] |
|---|---|
| Description | Does an acute bout of passive, warm water therapy reduce plasma [glucose]? Units for AUC are AU (arbitrary units) which have been derived from the trapezoidal method and have been published as such. Trapezoidal method: AUC = Δx ((y0/2)+y1+y2+y3+...+(yn/2)). |
| Time Frame | Visit 2, 3 and 4. 3 times in total, until study completion, approximately 8 weeks |
Outcome Measure Data
| Analysis Population Description |
|---|
| Individuals with T2DM (type 2 diabetes mellitus) |
| Arm/Group Title | Control | Pre OGTT | Post OGTT |
|---|---|---|---|
| Arm/Group Description | Participants will lie in a semi recumbent position in minimal clothing for the entirety of the visit. Initially, participants will be cannulated and blood samples drawn every 30 min of each experimental visit. Following cannulation an 180 min OGTT (75g) will commence in a thermoneutral room (~ 23C). During the OGTT, HR (heart rate) will be measured continuously, whilst blood pressure, deep body temperature (rectal probe) and resting metabolic rate will be assessed every 30 min. | Condition 2 will employ identical procedures to condition 1, except thirty minutes into the OGTT, the participant will be immersed into an immersion tank (~39oC) for 60 min. Water temperature will be manipulated as required to achieve and maintain a target Trec at 38.5 oC using water between 37.5 and 39oC, and then participants will be removed horizontally back into the thermoneutral room for the reminder of the OGTT. Participants will be towel dried and given a towelled robe to wear. Heating: Warm water immersion | Condition 3 will employ identical procedures to condition 2, with the exception that the heating via immersion will start as soon as the participant is instrumented (and following a 15 min rest period) and the OGTT will commence 30 min after the 60 min immersion time for a further 180 min. Heating: Warm water immersion |
| Measure Participants | 12 | 12 | 12 |
| Mean (Standard Deviation) [AU] |
1677
(386)
|
1797
(340)
|
1662
(364)
|
| Title | Change in Plasma [Insulin] |
|---|---|
| Description | Does plasma [insulin] reduce more if the passive, warm water therapy is conducted before or after the OGTT? |
| Time Frame | Visit 2, 3 and 4. 3 times in total, until study completion, approximately 8 weeks |
Outcome Measure Data
| Analysis Population Description |
|---|
| Individuals with T2DM |
| Arm/Group Title | Control | Pre OGTT | Post OGTT |
|---|---|---|---|
| Arm/Group Description | Participants will lie in a semi recumbent position in minimal clothing for the entirety of the visit. Initially, participants will be cannulated and blood samples drawn.every 30 min of each experimental visit. Following cannulation an 180 min OGTT (75g) will commence in a thermoneutral room (~ 23C). During the OGTT, HR will be measured continuously, whilst blood pressure, deep body temperature (rectal probe) and resting metabolic rate will be assessed every 30 min. | Condition 2 will employ identical procedures to condition 1, except thirty minutes into the OGTT, the participant will be immersed into an immersion tank (~39oC) for 60 min. Water temperature will be manipulated as required to achieve and maintain a target Trec at 38.5 oC using water between 37.5 and 39oC, and then participants will be removed horizontally back into the thermoneutral room for the reminder of the OGTT. Participants will be towel dried and given a towelled robe to wear. Heating: Warm water immersion | Condition 3 will employ identical procedures to condition 2, with the exception that the heating via immersion will start as soon as the participant is instrumented (and following a 15 min rest period) and the OGTT will commence 30 min after the 60 min immersion time for a further 180 min. Heating: Warm water immersion |
| Measure Participants | 12 | 12 | 12 |
| Mean (Standard Deviation) [µU/mL] |
75.18
(68.94)
|
48.79
(35.11)
|
79.86
(63.91)
|
| Title | Mean Insulin Sensitivity |
|---|---|
| Description | Does insulin sensitivity increase following an acute bout of warm water therapy? Calculation of insulin sensitivity is measured in AU which have been derived from the Gutt method and have been published as such. Gutt insulin sensitivity = [75,000 + (G0-G120) × 0.19 × BW]/(120 × log [(I0 + I120)/2] × [(G0 + G120)/2]). Where G = plasma [glucose], I = plasma [insulin] and BW = body weight. |
| Time Frame | Visit 2, 3 and 4. 3 times in total, until study completion, approximately 8 weeks |
Outcome Measure Data
| Analysis Population Description |
|---|
| Individuals with T2DM |
| Arm/Group Title | Control | Pre OGTT | Post OGTT |
|---|---|---|---|
| Arm/Group Description | Participants will lie in a semi recumbent position in minimal clothing for the entirety of the visit. Initially, participants will be cannulated and blood samples drawn.every 30 min of each experimental visit. Following cannulation an 180 min OGTT (75g) will commence in a thermoneutral room (~ 23C). During the OGTT, HR will be measured continuously, whilst blood pressure, deep body temperature (rectal probe) and resting metabolic rate will be assessed every 30 min. | Condition 2 will employ identical procedures to condition 1, except thirty minutes into the OGTT, the participant will be immersed into an immersion tank (~39oC) for 60 min. Water temperature will be manipulated as required to achieve and maintain a target Trec at 38.5 oC using water between 37.5 and 39oC, and then participants will be removed horizontally back into the thermoneutral room for the reminder of the OGTT. Participants will be towel dried and given a towelled robe to wear. Heating: Warm water immersion | Condition 3 will employ identical procedures to condition 2, with the exception that the heating via immersion will start as soon as the participant is instrumented (and following a 15 min rest period) and the OGTT will commence 30 min after the 60 min immersion time for a further 180 min. Heating: Warm water immersion |
| Measure Participants | 12 | 12 | 12 |
| Mean (Standard Deviation) [AU] |
52.00
(11.56)
|
47.45
(13.86)
|
56.51
(13.85)
|
| Title | Change in Fuel Utilisation |
|---|---|
| Description | Does carbohydrate and fat (RER) utilisation alter during and following an acute bout of warm water therapy? |
| Time Frame | Visit 2, 3 and 4. 3 times in total, until study completion, approximately 8 weeks |
Outcome Measure Data
| Analysis Population Description |
|---|
| Individuals with T2DM |
| Arm/Group Title | Control | Pre OGTT | Post OGTT |
|---|---|---|---|
| Arm/Group Description | Participants will lie in a semi recumbent position in minimal clothing for the entirety of the visit. Initially, participants will be cannulated and blood samples drawn.every 30 min of each experimental visit. Following cannulation an 180 min OGTT (75g) will commence in a thermoneutral room (~ 23C). During the OGTT, HR will be measured continuously, whilst blood pressure, deep body temperature (rectal probe) and resting metabolic rate will be assessed every 30 min. | Condition 2 will employ identical procedures to condition 1, except thirty minutes into the OGTT, the participant will be immersed into an immersion tank (~39oC) for 60 min. Water temperature will be manipulated as required to achieve and maintain a target Trec at 38.5 oC using water between 37.5 and 39oC, and then participants will be removed horizontally back into the thermoneutral room for the reminder of the OGTT. Participants will be towel dried and given a towelled robe to wear. Heating: Warm water immersion | Condition 3 will employ identical procedures to condition 2, with the exception that the heating via immersion will start as soon as the participant is instrumented (and following a 15 min rest period) and the OGTT will commence 30 min after the 60 min immersion time for a further 180 min. Heating: Warm water immersion |
| Measure Participants | 12 | 12 | 12 |
| Mean (Standard Deviation) [kcal] |
263
(33)
|
278
(40)
|
304
(38)
|
| Title | Change in Cardiovascular Status |
|---|---|
| Description | Does heart rate (variability) change during or after an acute bout of warm water therapy? |
| Time Frame | Visit 2, 3 and 4. 3 times in total, until study completion, approximately 8 weeks |
Outcome Measure Data
| Analysis Population Description |
|---|
| 0 participants analysed due to immersion for passive heating causing too much noise in the data for it to be valid. |
| Arm/Group Title | Control | Pre OGTT | Post OGTT |
|---|---|---|---|
| Arm/Group Description | Participants will lie in a semi recumbent position in minimal clothing for the entirety of the visit. Initially, participants will be cannulated and blood samples drawn every 30 min of each experimental visit. Following cannulation an 180 min OGTT (75g) will commence in a thermoneutral room (~ 23C). During the OGTT, HR (heart rate) will be measured continuously, whilst blood pressure, deep body temperature (rectal probe) and resting metabolic rate will be assessed every 30 min. | Condition 2 will employ identical procedures to condition 1, except thirty minutes into the OGTT, the participant will be immersed into an immersion tank (~39oC) for 60 min. Water temperature will be manipulated as required to achieve and maintain a target Trec at 38.5 oC using water between 37.5 and 39oC, and then participants will be removed horizontally back into the thermoneutral room for the reminder of the OGTT. Participants will be towel dried and given a towelled robe to wear. Heating: Warm water immersion | Condition 3 will employ identical procedures to condition 2, with the exception that the heating via immersion will start as soon as the participant is instrumented (and following a 15 min rest period) and the OGTT will commence 30 min after the 60 min immersion time for a further 180 min. Heating: Warm water immersion |
| Measure Participants | 0 | 0 | 0 |
| Title | Change in eHSP70 (Extracellular Heat Shock Protein 70) |
|---|---|
| Description | Does eHSP increases during and following an acute bout of warm water therapy? |
| Time Frame | Visit 2, 3 and 4. 3 times in total, until study completion, approximately 8 weeks |
Outcome Measure Data
| Analysis Population Description |
|---|
| Individuals with T2DM |
| Arm/Group Title | Control | Pre OGTT | Post OGTT |
|---|---|---|---|
| Arm/Group Description | Participants will lie in a semi recumbent position in minimal clothing for the entirety of the visit. Initially, participants will be cannulated and blood samples drawn.every 30 min of each experimental visit. Following cannulation an 180 min OGTT (75g) will commence in a thermoneutral room (~ 23C). During the OGTT, HR will be measured continuously, whilst blood pressure, deep body temperature (rectal probe) and resting metabolic rate will be assessed every 30 min. | Condition 2 will employ identical procedures to condition 1, except thirty minutes into the OGTT, the participant will be immersed into an immersion tank (~39oC) for 60 min. Water temperature will be manipulated as required to achieve and maintain a target Trec at 38.5 oC using water between 37.5 and 39oC, and then participants will be removed horizontally back into the thermoneutral room for the reminder of the OGTT. Participants will be towel dried and given a towelled robe to wear. Heating: Warm water immersion | Condition 3 will employ identical procedures to condition 2, with the exception that the heating via immersion will start as soon as the participant is instrumented (and following a 15 min rest period) and the OGTT will commence 30 min after the 60 min immersion time for a further 180 min. Heating: Warm water immersion |
| Measure Participants | 8 | 8 | 8 |
| Mean (Standard Deviation) [pg/mL] |
324
(154)
|
507
(112)
|
364
(81)
|
| Title | Change in Inflammatory Status |
|---|---|
| Description | Does inflammatory status (IL-6 & IL-10) change during or after an acute bout of warm water therapy? |
| Time Frame | Visit 2, 3 and 4. 3 times in total, until study completion, approximately 8 weeks |
Outcome Measure Data
| Analysis Population Description |
|---|
| 0 participants analysed due to lack of funds as a result of the COVID-19 pandemic. Data for this has not been collected and will not be in the future. |
| Arm/Group Title | Control | Pre OGTT | Post OGTT |
|---|---|---|---|
| Arm/Group Description | Participants will lie in a semi recumbent position in minimal clothing for the entirety of the visit. Initially, participants will be cannulated and blood samples drawn every 30 min of each experimental visit. Following cannulation an 180 min OGTT (75g) will commence in a thermoneutral room (~ 23C). During the OGTT, HR (heart rate) will be measured continuously, whilst blood pressure, deep body temperature (rectal probe) and resting metabolic rate will be assessed every 30 min. | Condition 2 will employ identical procedures to condition 1, except thirty minutes into the OGTT, the participant will be immersed into an immersion tank (~39oC) for 60 min. Water temperature will be manipulated as required to achieve and maintain a target Trec at 38.5 oC using water between 37.5 and 39oC, and then participants will be removed horizontally back into the thermoneutral room for the reminder of the OGTT. Participants will be towel dried and given a towelled robe to wear. Heating: Warm water immersion | Condition 3 will employ identical procedures to condition 2, with the exception that the heating via immersion will start as soon as the participant is instrumented (and following a 15 min rest period) and the OGTT will commence 30 min after the 60 min immersion time for a further 180 min. Heating: Warm water immersion |
| Measure Participants | 0 | 0 | 0 |
Adverse Events
| Time Frame | 3h for the OGTT plus the 1 h of passive heating in the passive heating arms at Visit 2, 3 and 4. 3 times in total, until study completion, up to approximately 8 weeks. | |||||
|---|---|---|---|---|---|---|
| Adverse Event Reporting Description | Safety population included all participants who underwent the OGTT and passive heating. | |||||
| Arm/Group Title | Control | Pre OGTT | Post OGTT | |||
| Arm/Group Description | Participants will lie in a semi recumbent position in minimal clothing for the entirety of the visit. Initially, participants will be cannulated and blood samples drawn.every 30 min of each experimental visit. Following cannulation an 180 min OGTT (75g) will commence in a thermoneutral room (~ 23C). During the OGTT, HR will be measured continuously, whilst blood pressure, deep body temperature (rectal probe) and resting metabolic rate will be assessed every 30 min. | Condition 2 will employ identical procedures to condition 1, except thirty minutes into the OGTT, the participant will be immersed into an immersion tank (~39oC) for 60 min. Water temperature will be manipulated as required to achieve and maintain a target Trec at 38.5 oC using water between 37.5 and 39oC, and then participants will be removed horizontally back into the thermoneutral room for the reminder of the OGTT. Participants will be towel dried and given a towelled robe to wear. Heating: Warm water immersion | Condition 3 will employ identical procedures to condition 2, with the exception that the heating via immersion will start as soon as the participant is instrumented (and following a 15 min rest period) and the OGTT will commence 30 min after the 60 min immersion time for a further 180 min. Heating: Warm water immersion | |||
All Cause Mortality |
||||||
| Control | Pre OGTT | Post OGTT | ||||
| Affected / at Risk (%) | # Events | Affected / at Risk (%) | # Events | Affected / at Risk (%) | # Events | |
| Total | 0/12 (0%) | 0/12 (0%) | 0/12 (0%) | |||
Serious Adverse Events |
||||||
| Control | Pre OGTT | Post OGTT | ||||
| Affected / at Risk (%) | # Events | Affected / at Risk (%) | # Events | Affected / at Risk (%) | # Events | |
| Total | 0/12 (0%) | 0/12 (0%) | 0/12 (0%) | |||
Other (Not Including Serious) Adverse Events |
||||||
| Control | Pre OGTT | Post OGTT | ||||
| Affected / at Risk (%) | # Events | Affected / at Risk (%) | # Events | Affected / at Risk (%) | # Events | |
| Total | 0/12 (0%) | 1/12 (8.3%) | 2/12 (16.7%) | |||
| Investigations | ||||||
| Vasovagal syncope | 0/12 (0%) | 0 | 0/12 (0%) | 0 | 2/12 (16.7%) | 2 |
| Surgical and medical procedures | ||||||
| Pain on cannulation | 0/12 (0%) | 0 | 1/12 (8.3%) | 1 | 0/12 (0%) | 0 |
Limitations/Caveats
More Information
Certain Agreements
All Principal Investigators ARE employed by the organization sponsoring the study.
There is NOT an agreement between Principal Investigators and the Sponsor (or its agents) that restricts the PI's rights to discuss or publish trial results after the trial is completed.
Results Point of Contact
| Name/Title | Dr. Ant Shepherd |
|---|---|
| Organization | University of Portsmouth |
| Phone | 02392845289 |
| ant.shepherd@port.ac.uk |
- 003AS