Sauna for Long Covid

A Pilot Study of Whole Body Hyperthermia for Long Covid or Post-Acute Sequelae of COVID-19 (PASC)

Research suggests that Whole Body Hyperthermia in a sauna-like environment can reduce symptoms related to post-acute sequelae of SARS-CoV-2 (PASC), or Long Covid. The investigators aim to study the feasibility and treatment effect of this procedure for patients experiencing Long Covid symptoms.

Study Overview

• Status: Recruiting
• Conditions: Long COVID
• Intervention / Treatment: Device: whole body hyperthermia

Detailed Description

This proposed trial will examine, for the first-time, study whole-body hyperthermia (WBH) as a treatment for PASC. The investigators will enroll 21 people with PASC who will be randomized into two conditions with different temperature WBH. The primary aims will explore acceptability and feasibility, reduction of fatigue (primary symptom), and potential mechanisms (inflammation and sleep). Inflammation and sleep have both been shown to be dysregulated in PASC and addressed by WBH in other populations. The investigators will use week 2 as the primary endpoint. However, patients will be followed for 4 and 6 weeks to monitor the duration of effect.

• Study Type: Interventional
• Enrollment (Estimated): 21
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Maren Nyer, PhD; Phone Number: 6072796290; Email: mnyer@mgh.harvard.edu
• Study Contact Backup: Name: David Mischoulon, MD, PhD; Email: dmischoulon@mgh.harvard.edu

Study Locations

• United States
  • Massachusetts
    • Boston, Massachusetts, United States, 02114
      • Recruiting
      • Depression Clinical and Research Program
      • Contact: Maren Nyer, PhD; Phone Number: 617-643-4897; Email: mnyer@partners.org
      • Contact: David Mischoulon, MD, PhD; Email: dmischoulon@partners.org
      • Principal Investigator: Maren Nyer, PhD

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

1. 18-65 years of age
2. English language proficiency
3. Ability to provide informed consent
4. Ability to lie supine (on back) for 2 hours (required for sauna sessions)
5. Must have had clinically suspected COVID-19 and a positive antibody test or a documented SARS-CoV-2 infection (a positive reverse transcription polymerase chain reaction test) at least 12 weeks prior to Screening (Note: clinician judgment can override lack of positive COVID test with clear Long Covid onset and presentation)
6. The Patient Reported Outcome Measurement Information System Fatigue-Short Form v1.0 -Fatigue 7a (PROMIS F-SF43) raw score of 21 or greater at Screening (onset of fatigue confirmed post-infection as in other studies of PASC)
7. Individuals of childbearing potential must use an acceptable form of birth control.

Exclusion Criteria:

1. Fatigue for known reasons other than PASC (e.g. longstanding diagnosis of Chronic Fatigue Syndrome pre-dating Long Covid, low thyroid, multiple sclerosis, AIDS related fatigue, mononucleosis), as determined by clinical discretion of study investigators
2. Known hypersensitivity to infrared heat exposure, significant history of heat stroke
3. Breastfeeding, pregnancy or planned pregnancy during study
4. Active suicidal intent
5. History of bipolar disorder, psychotic disorders, eating disorders, obsessive compulsive disorder, and/or substance use or dependence (within the last year), as per the Mini-International Neuropsychiatric Interview (MINI)44
6. Positive urine toxicology screen for illicit drug use
7. Any serious unstable medical condition
8. Inability to fit into the sauna device. Morbid obesity (BMI > 40) and/or body shape that might increase the risk of cutaneous burning from the device (because of skin being too close to the heat).
9. Back pain that would interfere with ability to lay on hard surface
10. Using medication that might impact thermoregulatory capacity and cannot be held for an appropriate length (at least one half-life) as determined by clinician judgment prior to receiving WBH treatment
11. Breast Implants
12. Claustrophobia that would interfere with ability to remain in sauna
13. Unsafe cardiac status as defined by abnormal ECG reading at screening visit or as determined by study doctor or subject's physician
14. History of or current diagnosis of thrombosis or thrombophilia
15. History of hemophilia
16. History of febrile seizures or seizure disorders
17. Any new treatments/medications for long-COVID that have started in the past 3 months
18. A subject who in the opinion of the Principal Investigator would not be able to safely complete the study or would jeopardize study integrity.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: verum whole body hyperthermia; WBH will be completed with a Clearlight Sauna Dome and ancillary equipment to monitor core body temperature. For the verum WBH, participants will be brought to a core body temperature of 101.3°F.	Device: whole body hyperthermia; heat will be applied to the participant through a sauna to increase core body temperature
Sham Comparator: sham whole body hyperthermia; The sham condition will be identical to the active WBH condition. Time and other procedures will be consistent. Mild heat will be used to mimic an active WBH session.	Device: whole body hyperthermia; heat will be applied to the participant through a sauna to increase core body temperature

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
The Patient Reported Outcome Measurement Information System Fatigue-Short Form v1.0 -Fatigue 7a (PROMIS F-SF)	provides a more in depth assessment of fatigue as compared to the PROMIS 29 and consists of 7 items that measure both the experience of fatigue and the interference of fatigue on daily activities over the past week. Uses a range of 7-35, higher scores indicate higher fatigue.	2-weeks (primary endpoint) follow up at 6 weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Patient-Reported Outcomes Measurement Information System (PROMIS-29)	assesses seven health domains (i.e., physical function, fatigue, pain interference, depressive symptoms, anxiety, ability to participate in social roles and activities, and sleep disturbance) using four items per domain. There is no total score, and scores range from 4-10 for each health domain (with 4 items for each of the 7 health domains). Scores are transformed into t scores with higher scores indicating better health.	2-weeks (primary endpoint) follow up at 6 weeks
Patient Health Questionnaire-9 (PHQ)	a well-established, brief self-administered 9-item depression screening and monitoring tool. Uses a range of 0-27 with higher scores indicating greater depressive symptoms.	2-weeks (primary endpoint) follow up at 6 weeks
The Perceived Stress Scale (PSS)	consists of 10 items and measures the frequency with which perceived stressful life situations are experienced. Scores can range from 0 to 40 with higher scores indicating higher perceived stress.	2-weeks (primary endpoint) follow up at 6 weeks
Patient-Reported Outcomes Measurement Information System Cognitive Abilities	items target positive self-assessments of cognitive functioning with a total of 8 items. Raw scores can range from 8 to 40. The raw score is then converted to a t-score and higher scores indicate better perceived cognitive functioning.	2-weeks (primary endpoint) follow up at 6 weeks
Patient-Reported Outcomes Measurement Information System Cognitive Concerns	items are worded negatively and express concerns in the same areas as in the Patient-Reported Outcomes Measurement Information System Cognitive Abilities with a total of 8 items. Raw scores can range from 8 to 40. The raw score is then converted to a t-score and higher scores indicate greater cognitive concerns.	2-weeks (primary endpoint) follow up at 6 weeks
Positive and Negative Affective Schedule (PANAS)	consists of two 10-item mood scales to measure positive and negative affect. Raw scores range from 10 to 50. Higher scores indicate more of a positive affect.	2-weeks (primary endpoint) follow up at 6 weeks
The Composite Autonomic Symptom Score (COMPASS-31)	consists of 31 items and measures autonomic and neurodegenerative system symptoms. Total scores range from 0 to 100 with greater scores indicating greater autonomic dysfunction.	2-weeks (primary endpoint) follow up at 6 weeks
The Functional Assessment of Chronic Illness Therapy Fatigue Scale (FACIT-F)	13-item questionnaire designed to assess the severity of fatigue and its impact on daily functioning and quality of life. Respondents rate items on a 5-point scale, with higher scores indicating less fatigue. Total scores can range between 0 and 52.	2-weeks (primary endpoint) follow up at 6 weeks
Long-COVID Symptom Tool (Long-COVID ST)	assess the symptoms of long COVID-19 created from patients' lived experience that measures 10 different physiological domains. Scores can range from 0 to 53 with higher scores indicating greater severity of symptoms.	2-weeks (primary endpoint) follow up at 6 weeks
Long-COVID Impact Tool (Long-COVID IT)	assess the symptoms of long COVID-19 created from patients' lived experience that measures 10 different physiological domains. The scale also measures the impact from these symptoms. Scores can range from 0 to 60 with higher scores indicating greater life impact.	2-weeks (primary endpoint) follow up at 6 weeks

Collaborators and Investigators

• Sponsor: Massachusetts General Hospital
• Collaborators: University of California, San Francisco

Study record dates

Study Major Dates

• Study Start (Estimated): August 1, 2026
• Primary Completion (Estimated): September 30, 2026
• Study Completion (Estimated): December 1, 2026

Study Registration Dates

• First Submitted: June 30, 2023
• First Submitted That Met QC Criteria: June 30, 2023
• First Posted (Actual): July 5, 2023

Study Record Updates

• Last Update Posted (Estimated): November 13, 2025
• Last Update Submitted That Met QC Criteria: November 11, 2025
• Last Verified: November 1, 2025

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Post-Infectious Disorders; COVID-19; Pathologic Processes; Chronic Disease; Disease Attributes; Respiratory Tract Infections; Infections; RNA Virus Infections; Virus Diseases; Respiratory Tract Diseases; Lung Diseases; Pneumonia, Viral; Pneumonia; Coronavirus Infections; Coronaviridae Infections; Nidovirales Infections; Pathological Conditions, Signs and Symptoms; Post-Acute COVID-19 Syndrome
• Other Study ID Numbers: 2023p000852

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No