Clinical trial NCT04767347: Renal Considerations in the Heat Stress Recommendations
Official title: Renal Considerations in the Heat Stress Recommendations
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Hot Weather; Adverse Effect
Kidney Dysfunction
Kidney Injury
Hyperthermia
Dehydration
Lead sponsor: Indiana University
Sponsor class: OTHER
Collaborators: name: State University of New York at Buffalo
First posted: 2021-02-23
Enrollment: 38
Sex: ALL
Minimum age (years): 18
Maximum age (years): 44
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: CROSSOVER
Intervention model description: This study will systematically examine the NIOSH recommendations for prescribing work-to-rest ratios during occupational heat stress on kidney function.
Primary purpose: BASIC_SCIENCE

Brief summary: An epidemic of chronic kidney disease is occurring in laborers who undertake physical work outdoors in hot conditions. The reason for this is unknown, but may be related to kidney dysfunction caused by increases in body temperature and dehydration. The current heat stress recommendations for workers were not developed with regards for kidney health. The purpose of this study is to determine if the current recommendations protect against kidney dysfunction.


Eligibility criteria: Inclusion Criteria:

* Men and women
* 18-44 y old
* Body mass index ≤35.0 kg/m2
* Self-reported to be healthy.

Exclusion Criteria:

* Not within defined age range
* Estimated glomerular filtration rate (eGFR) \< 60 mL/min/1.73m2
* Deemed highly active according to the physical activity questionnaire (i.e., \>3500 MET\*min/wk)
* Body mass index \>35.0 kg/m2
* Current or history of any renal disease, heart disease, stroke, immune or autoimmune disease, and/or gastrointestinal disease/surgery
* Hypertension during screening (systolic blood pressure \>139 or diastolic blood pressure \>89)
* Using medications that blunt the physiological response to exercise (e.g., beta blockers)
* Prescription medication with a known side effect of impaired temperature regulation or fluid balance (e.g., diuretics)
* Positive pregnancy test at any time during the study or breast feeding
* Current tobacco or electronic cigarette use or consistent use within the last 2 years
* Inability to safely complete the peak oxygen uptake test

Primary outcomes:
measure: Peak urinary [IGFBP7•TIMP-2]
timeFrame: through study completion, up to 20 weeks
Secondary outcomes:
measure: Urinary NGAL
timeFrame: through study completion, up to 20 weeks
measure: Urinary IGFBP7
timeFrame: through study completion, up to 20 weeks
measure: Urinary TIMP-2
timeFrame: through study completion, up to 20 weeks
measure: Urinary IL-18
timeFrame: through study completion, up to 20 weeks
measure: Urinary L-FABP
timeFrame: through study completion, up to 20 weeks
measure: Renal artery blood velocity
timeFrame: through study completion, up to 20 weeks
measure: Segmental artery blood velocity
timeFrame: through study completion, up to 20 weeks
Other outcomes:
measure: Core body temperature
timeFrame: through study completion, up to 20 weeks
measure: Mean skin temperature
timeFrame: through study completion, up to 20 weeks
measure: Oxygen uptake
timeFrame: through study completion, up to 20 weeks
measure: Heart rate
timeFrame: through study completion, up to 20 weeks
measure: Blood pressure
timeFrame: through study completion, up to 20 weeks
measure: Whole-body sweat rate
timeFrame: through study completion, up to 20 weeks
measure: Percentage change in body weight
timeFrame: through study completion, up to 20 weeks
measure: Plasma osmolality
timeFrame: through study completion, up to 20 weeks
measure: Urine osmolality
timeFrame: through study completion, up to 20 weeks
measure: Blood and plasma volume
timeFrame: through study completion, up to 20 weeks
measure: Urine specific gravity
timeFrame: through study completion, up to 20 weeks
measure: Plasma copeptin
timeFrame: through study completion, up to 20 weeks
measure: Creatinine clearance
timeFrame: through study completion, up to 20 weeks
measure: Fractional excretion of electrolytes
timeFrame: through study completion, up to 20 weeks
measure: Free water clearance
timeFrame: through study completion, up to 20 weeks
measure: Serum uric acid
timeFrame: through study completion, up to 20 weeks
measure: Urinary uric acid
timeFrame: through study completion, up to 20 weeks
Locations:
city: Bloomington
country: United States
facility: School of Public Health
state: Indiana
Study officials:
References:
citation: Hess HW, Tarr ML, Baker TB, Hostler D, Schlader ZJ. Ad libitum drinking prevents dehydration during physical work in the heat when adhering to occupational heat stress recommendations. Temperature (Austin). 2022 Jul 20;9(3):292-302. doi: 10.1080/23328940.2022.2094160. eCollection 2022.