Cold therapy for asthma
Evidence review
Overview
In laboratory studies of asthmatic subjects, a 1-minute cold shower at 59 F followed by 1 minute of wind on the wet skin produced significant airway obstruction, while a warm shower or breathing the cold mist alone did not. Breathing warm humidified air during cooling substantially reduced the response, suggesting that body cooling leads to cooling of the airways. No trial has evaluated cold plunges, cold showers or whole-body cryotherapy as therapy in asthma.
Key findings
- Cold shower 59 F for 1 min plus wind: FEV1 fell to 79% and MMEF to 72% of baseline, airway resistance rose to 198% in asthmatics (Chen 1978, n=8 asthmatic, 5 normal)
- Breathing warm humidified air substantially reduced cooling-induced bronchoconstriction (Horton 1979, n=16)
Every study we reviewed
2 found harm
Each study was checked on PubMed. The colored edge shows the direction of the result. The research library lists 5 studies on asthma, across all heat and cold therapies, including case reports and older work not graded here.
Airways obstruction in asthmatics induced by body cooling.
Chen WY et al. Scand J Respir Dis. 1978. PubMed 653323
- Who
- 8 asthmatic subjects and 5 normal subjects
- What
- body cooling: cold shower at 59 F (15 C) for 1 min, then wet body exposed to fan wind for 1 min; comparison warm shower at 98.6 F (37 C) and breathing cold shower mist
- Protocol
- 59 °F · 1 (plus 1 min wind) min · single challenge/wk
- Measured
- FEV1, MMEF, thoracic gas volume, airway resistance
- Result
- In asthmatics FEV1 fell to a mean 79% and MMEF to 72% of baseline, and airway resistance rose to 198% (P<.05); normal subjects had only a small rise in airway resistance. No obstruction after a 98.6 F shower or after breathing the cold mist.
- Limitations
- acute laboratory challenge; very small; not a therapeutic protocol
Effects of breathing warm humidified air on bronchoconstriction induced by body cooling and by inhalation of methacholine.
Horton DJ et al. Chest. 1979. PubMed 421517 · DOI
- Who
- asthmatic subjects (two groups of 8)
- What
- body cooling by 1-min cold shower at 59 F (15 C) then wind, breathing room air vs warm humidified air (methacholine challenge in the second group)
- Protocol
- 59 °F · 1 (plus 1 min wind) min · single challenge/wk
- Measured
- bronchoconstriction (pulmonary function)
- Result
- Body cooling induced bronchoconstriction, which was substantially reduced by breathing warm humidified air; warm air did not reduce methacholine-induced bronchoconstriction. Figures not given in abstract.
- Limitations
- acute laboratory challenge; small; figures not in abstract
Protocols used in the studies
Both studies used a single 1-minute cold shower at 59 F (15 C) followed by 1 minute of fan-generated wind on the wet body, with pulmonary function measured before and after.
What is still unknown
Whether gradual or habitual cold exposure changes airway responsiveness; safety of cold-water immersion and whole-body cryotherapy in controlled asthma; any therapeutic effect.
Safety
Cautions for cold therapy in this condition
- Body cooling can trigger bronchoconstriction in asthma (PMID 653323); this is relevant to cold plunges, cold showers and cooling after sauna.
- A child with asthma had an attack while using a cold shower after a sauna (PMID 2281065).
- See general cold safety entry.
For clinicians
Suggested rationale
No study supports cold-water exposure as a treatment for asthma; in small challenge studies a 1-minute 59 F shower followed by wind reduced FEV1 to 79% of baseline in asthmatic subjects (Chen 1978), so cold exposure warrants caution in patients with asthma.
Suggested wording only. The treating clinician decides whether it reflects their clinical judgment for this patient.
Typical ICD-10 codes: J45.909, J45.990. Examples only; the clinician assigns the code.
What a letter of medical necessity should containWho can write it: physicians, NPs, PAs and others