Sauna for ankylosing spondylitis / axial spondyloarthritis
Evidence review
Overview
In a German randomized trial of 35 inpatients with ankylosing spondylitis, adding six sessions of water-filtered infrared-A whole-body hyperthermia (a clinic radiant-heat device) to physical therapy gave greater pain relief, less analgesic use and improvements in BASDAI and BASFI lasting up to 3-6 months, while HAQ did not change. In a small infrared-sauna pilot, pain and stiffness fell during sessions without increased disease activity. A randomized spa-exercise program that included sauna at one site improved a pooled symptom index at 4 weeks, but sauna's own contribution is unknown. Mechanistic studies report lower pro-inflammatory cytokines after whole-body hyperthermia and no cortisol or lymphocyte change after a single hot bath.
Key findings
- RCT, n=35 inpatients: 6 sessions of water-filtered infrared-A whole-body hyperthermia added to physical therapy gave significantly greater pain relief than physical therapy alone, with BASDAI and BASFI improving only in the hyperthermia group (up to 6 and 3 months); HAQ unchanged in both groups (Lange 2017)
- Infrared sauna, 8 sessions over 4 weeks (n=17 AS): pain and stiffness fell significantly during sessions (p<0.001); 4-week changes not statistically significant; no disease flare (Oosterveld 2009)
- RCT, n=120: 3-week spa-exercise therapy (one arm including sauna) vs usual care; pooled index of change difference 0.46 (95% CI 0.15-0.78) at week 4 for the sauna-site arm, 0.34 (95% CI -0.05 to 0.73) at week 16 (van Tubergen 2001)
- Mild whole-body hyperthermia, 9 cycles (n=12 AS): TNF-alpha, IL-1beta and IL-6 reduced by 40-50% (Tarner 2009)
- Single 50-minute hot bath to 101.3 F body temperature (12 AS, 12 healthy): no change in cortisol or lymphocyte subsets (Lange 2005)
- Controlled study of whole-body hyperthermia in AS: reduced blood viscosity and analgesic use and improved mobility reported, without numbers in the abstract (Matrai 1991)
Every study we reviewed
3 mixed results · 3 found benefit · 1 found no effect
Each study was checked on PubMed. The colored edge shows the direction of the result. The research library lists 23 studies on ankylosing spondylitis, across all heat and cold therapies, including case reports and older work not graded here.
Infrared sauna in patients with rheumatoid arthritis and ankylosing spondylitis. A pilot study showing good tolerance, short-term improvement of pain and stiffness, and a trend towards long-term beneficial effects.
Oosterveld FG et al. Clin Rheumatol. 2009. PubMed 18685882 · DOI · Free full text
- Who
- 17 patients with ankylosing spondylitis and 17 with rheumatoid arthritis (Netherlands)
- What
- Infrared sauna, series of 8 treatments over 4 weeks
- Protocol
- 2/wk · 4 wk
- Measured
- Pain, stiffness, fatigue, disease activity
- Result
- AS subgroup (n=17): pain and stiffness decreased significantly during an IR session (p<0.001); improvements over the 4-week period clinically relevant but not statistically significant; no relevant change in disease activity; no adverse effects
- Limitations
- Uncontrolled pilot; 17 AS patients; abstract-level data
Combined spa-exercise therapy is effective in patients with ankylosing spondylitis: a randomized controlled trial.
van Tubergen A et al. Arthritis Rheum. 2001. PubMed 11642642 · DOI
- Who
- Dutch outpatients with ankylosing spondylitis
- What
- 3-week spa-exercise therapy (group exercise, walking, hydrotherapy, sports, plus sauna at the Dutch site or radon-gallery visits at the Austrian site) vs usual drugs and weekly group physiotherapy
- Protocol
- 3 wk
- Measured
- Pooled index of change (function, global well-being, pain, morning stiffness)
- Result
- Sauna-site arm vs control: mean PIC difference 0.46 (95% CI 0.15-0.78, p=0.005) at week 4 and 0.34 (95% CI -0.05 to 0.73, p=0.086) at week 16; no difference at weeks 28 and 40
- Limitations
- Multicomponent intervention; sauna effect cannot be isolated; unblinded
The effect of mild whole-body hyperthermia on systemic levels of TNF-alpha, IL-1beta, and IL-6 in patients with ankylosing spondylitis.
Tarner IH et al. Clin Rheumatol. 2009. PubMed 19089489 · DOI
- Who
- 12 men with ankylosing spondylitis and 12 healthy controls (Germany)
- What
- Mild whole-body hyperthermia, 9 cycles
- Protocol
- 101.3 core target °F · 50 min
- Measured
- Serum TNF-alpha, IL-1beta, IL-6
- Result
- In AS patients hyperthermia reduced all three cytokines by 40-50%
- Limitations
- Mechanistic outcome only; no clinical endpoints in abstract; men with clinically inactive AS; hyperthermia device, not sauna
Whole body hyperthermia treatment increases interleukin 10 and toll-like receptor 4 expression in patients with ankylosing spondylitis: a pilot study.
Zauner D et al. Int J Hyperthermia. 2014. PubMed 25256892 · DOI · Free full text
- Who
- 6 AS patients and 10 healthy controls (Austria)
- What
- Single moderate whole-body hyperthermia session
- Protocol
- 101.7-102.2 core °F · 60 min · 1/wk
- Measured
- Immune gene expression, cytokines, acute phase reactants
- Result
- IL-10, TLR-4 and HSPB1 expression rose up to 3 h after treatment; no significant change in systemic cytokine concentrations or acute phase reactants
- Limitations
- Six patients; single session; mechanistic outcomes only
[Hemorheologic and clinical changes in ankylosing spondylitis during hyperthermia].
Matrai A et al. Acta Med Austriaca. 1991. PubMed 1796724
- Who
- Patients with ankylosing spondylitis (Austria)
- What
- Whole-body hyperthermia (clinic-delivered), not a sauna
- Measured
- Blood and plasma viscosity, red cell deformability, analgesic use, mobility, well-being
- Result
- Authors report reduced blood and plasma viscosity, normalized red cell deformability, reduced analgesic use, increased mobility and improved well-being; no numbers in abstract
- Limitations
- German-language; sample size, protocol and statistics not in abstract; hyperthermia, not sauna
Effect of iterative whole-body hyperthermia with water-filtered infrared-A radiation in ankylosing spondylitis: a controlled, randomized, prospective study
Lange U et al. Aktuelle Rheumatologie. 2017. Not in PubMed: source · DOIGerman publication; title and summary translated by SaunaLMN. Original title: Wirkung iterativer Ganzkörperhyperthermie mit wassergefilterter Infrarot-A-Strahlung bei ankylosierender Spondylitis – eine kontrollierte, randomisierte, prospektive Studie
- Who
- Hospital inpatients with ankylosing spondylitis (Germany); medication comparable between groups
- What
- Whole-body hyperthermia with water-filtered infrared-A radiation (clinic radiant-heat device, not a sauna), 6 sessions, added to standardized physical therapy (n=20) vs standardized physical therapy alone (n=15)
- Measured
- Pain (VAS), BASDAI, BASFI, HAQ, FFbH, ESR, CRP, TNF-alpha, IL-1beta, IL-6; follow-up to 3 months (6 months in the hyperthermia group)
- Result
- Pain relief significantly greater with hyperthermia than control over follow-up, with reduced NSAID/analgesic use; BASDAI and BASFI fell significantly only in the hyperthermia group (lasting up to 6 and 3 months); FFbH improved at 3 months vs baseline; HAQ did not improve significantly in either group; ESR fell in the hyperthermia group; TNF-alpha and IL-1beta fell at 3 months (TNF-alpha also fell in controls); IL-6 unchanged. No effect sizes in the abstract
- Limitations
- Small (n=35), unblinded, no sham; German-language abstract (translated by us); between-group effect sizes not reported; 6-month data collected in the hyperthermia group only; clinic hyperthermia device rather than a sauna
Effect of mild hyperthermia on blood levels of cortisol and lymphocyte subpopulations in patients with ankylosing spondylitis and in healthy people
Lange U et al. Physikalische Medizin, Rehabilitationsmedizin, Kurortmedizin. 2005. Not in PubMed: source · DOIGerman publication; title and summary translated by SaunaLMN. Original title: Einfluss der milden Hyperthermie auf die Blutspiegel von Kortisol und Lymphozytensubpopulationen bei Patienten mit ankylosierender Spondylitis und Gesunden
- Who
- 12 patients with ankylosing spondylitis without acute inflammatory activity and 12 healthy people of similar age (Germany)
- What
- Single hyperthermic full bath (hot-water immersion) continued until sublingual body temperature reached 101.3 F (38.5 C); bath duration 50 minutes
- Protocol
- 101.3 body-temperature target °F · 50 min · 1/wk
- Measured
- Serum cortisol, total lymphocytes and B, T, CD4 and CD8 subpopulations
- Result
- No significant change in cortisol, total lymphocytes or lymphocyte subpopulations over 4 hours, and no difference between patients and healthy controls; the authors conclude the benefit of hyperthermia in AS is probably not caused by a cortisol rise with immunosuppression
- Limitations
- Mechanistic outcomes only, no clinical endpoints; single session; 12 patients; German-language abstract (translated by us)
Protocols used in the studies
Randomized trial: 6 sessions of water-filtered infrared-A whole-body hyperthermia during an inpatient stay, added to physical therapy (session length and core target not given in the abstract). Infrared sauna: 8 sessions over 4 weeks (cabin temperature not given in abstract). Other mild whole-body hyperthermia studies targeted core temperatures of about 101.3-102.2 F (38.5-39 C) for 50-60 minutes, 1 to 9 sessions, by clinic device or hot bath; these are not saunas.
What is still unknown
No sham-controlled or sauna-specific randomized trial in axial spondyloarthritis; whether results with clinic hyperthermia devices transfer to conventional or infrared saunas; dose, durability beyond 6 months, and effects in highly active disease or during biologic therapy are unknown.
Safety
Cautions for sauna in this condition
- No disease-activity flare was seen over a 4-week infrared-sauna course (PMID 18685882).
- In the randomized hyperthermia trial, NSAID/analgesic use fell and the authors describe the treatment as well tolerated; adverse events were not itemized in the abstract (Lange 2017, DOI 10.1055/s-0042-116945).
- Whole-body hyperthermia studies enrolled clinically inactive AS (PMID 19089489); effects in highly active disease are unstudied.
- Next-day worsening of rheumatic pain after sauna is described, more in women and in non-inflammatory conditions; adequate cooling is advised (PMID 3265298).
- General contraindications include unstable angina, recent myocardial infarction and severe aortic stenosis; avoid alcohol during sauna use (PMID 11165553). AS can involve aortic valve disease, so cardiac history should be reviewed.
For clinicians
Suggested rationale
In a randomized trial in AS, adding six sessions of water-filtered infrared whole-body hyperthermia to physical therapy gave greater pain relief and improvements in BASDAI and BASFI lasting up to 3-6 months (Lange 2017), and an infrared-sauna pilot showed within-session relief of pain and stiffness without disease flare (Oosterveld 2009); sauna-type heat may be considered as an adjunct to exercise-based care, recognizing that the trial was small, unblinded and used a clinic hyperthermia device rather than a sauna.
Suggested wording only. The treating clinician decides whether it reflects their clinical judgment for this patient.
Typical ICD-10 codes: M45.9, M45.A0. Examples only; the clinician assigns the code.
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