{
  "cutoff": "2026-10-13",
  "note": "Selected publication milestones, not an exhaustive history or discovery priority claim.",
  "milestones": [
    {
      "pmid": "14564334",
      "year": "2003",
      "title": "Thermal hydrotherapy improves quality of life and hemodynamic function in patients with chronic heart failure.",
      "doi": "10.1016/S0002-8703(03)00314-4",
      "url": "https://pubmed.ncbi.nlm.nih.gov/14564334/",
      "interpretation": "Small controlled warm/cold hydrotherapy bundle has selected heart-failure symptom/function effects without isolating modalities."
    },
    {
      "pmid": "15564698",
      "year": "2004",
      "title": "Effects of repeated sauna treatment on ventricular arrhythmias in patients with chronic heart failure.",
      "doi": "10.1253/circj.68.1146",
      "url": "https://pubmed.ncbi.nlm.nih.gov/15564698/",
      "interpretation": "Supervised sauna reduces measured ectopy in a small heart-failure trial; hard-event reduction remains a different outcome."
    },
    {
      "pmid": "18922381",
      "year": "2008",
      "title": "Beneficial effects of Waon therapy on patients with chronic heart failure: results of a prospective multicenter study.",
      "doi": "10.1016/j.jjcc.2008.07.009",
      "url": "https://pubmed.ncbi.nlm.nih.gov/18922381/",
      "interpretation": "Multicenter Waon report adds short-term disease-specific cardiac and symptom data, with many within-arm contrasts."
    },
    {
      "pmid": "19154844",
      "year": "2009",
      "title": "Safety, acceptance, and physiologic effects of sauna bathing in people with chronic heart failure: a pilot report.",
      "doi": "10.1016/j.apmr.2008.06.029",
      "url": "https://pubmed.ncbi.nlm.nih.gov/19154844/",
      "interpretation": "Small supervised sauna crossover is tolerated but lacks significant between-arm function/QoL efficacy."
    },
    {
      "pmid": "19304125",
      "year": "2009",
      "title": "Waon therapy improves the prognosis of patients with chronic heart failure.",
      "doi": "10.1016/j.jjcc.2008.11.005",
      "url": "https://pubmed.ncbi.nlm.nih.gov/19304125/",
      "interpretation": "Matched severe-heart-failure Waon follow-up reports a five-year HF/cardiac-death composite association; allocation and primary-prevention scope remain unresolved."
    },
    {
      "pmid": "22863164",
      "year": "2012",
      "title": "Effects of sauna alone and postexercise sauna baths on blood pressure and hemodynamic variables in patients with untreated hypertension.",
      "doi": "10.1111/j.1751-7176.2012.00637.x",
      "url": "https://pubmed.ncbi.nlm.nih.gov/22863164/",
      "interpretation": "Acute sauna/exercise hypertension comparisons address short-term hemodynamics."
    },
    {
      "pmid": "25705824",
      "year": "2015",
      "title": "Association between sauna bathing and fatal cardiovascular and all-cause mortality events.",
      "doi": "10.1001/jamainternmed.2014.8187",
      "url": "https://pubmed.ncbi.nlm.nih.gov/25705824/",
      "interpretation": "Finnish male cohort links baseline sauna frequency/duration with fatal events prospectively."
    },
    {
      "pmid": "26174323",
      "year": "2015",
      "title": "Post-exercise cold water immersion attenuates acute anabolic signalling and long-term adaptations in muscle to strength training.",
      "doi": "10.1113/JP270570",
      "url": "https://pubmed.ncbi.nlm.nih.gov/26174323/",
      "interpretation": "Chronic cold recovery attenuates selected strength adaptation despite acute recovery rationale."
    },
    {
      "pmid": "27001189",
      "year": "2016",
      "title": "Waon Therapy for Managing Chronic Heart Failure　- Results From a Multicenter Prospective Randomized WAON-CHF Study.",
      "doi": "10.1253/circj.CJ-16-0051",
      "url": "https://pubmed.ncbi.nlm.nih.gov/27001189/",
      "interpretation": "WAON-CHF primaryBNP is null while selected secondary functional measures improve."
    },
    {
      "pmid": "27631616",
      "year": "2016",
      "title": "The Effect of Cold Showering on Health and Work: A Randomized Controlled Trial.",
      "doi": "10.1371/journal.pone.0161749",
      "url": "https://pubmed.ncbi.nlm.nih.gov/27631616/",
      "interpretation": "Unblinded cold showers reduce self-reported absence rather than overall illness days."
    },
    {
      "pmid": "28972808",
      "year": "2018",
      "title": "Joint associations of sauna bathing and cardiorespiratory fitness on cardiovascular and all-cause mortality risk: a long-term prospective cohort study.",
      "doi": "10.1080/07853890.2017.1387927",
      "url": "https://pubmed.ncbi.nlm.nih.gov/28972808/",
      "interpretation": "KIHD fitness/sauna joint analysis narrows measured confounding without creating independent exposure allocation."
    },
    {
      "pmid": "30486813",
      "year": "2018",
      "title": "Sauna bathing is associated with reduced cardiovascular mortality and improves risk prediction in men and women: a prospective cohort study.",
      "doi": "10.1186/s12916-018-1198-0",
      "url": "https://pubmed.ncbi.nlm.nih.gov/30486813/",
      "interpretation": "Older men-and-women Finnish cohort expands observational enrollment and adds fatal-event associations."
    },
    {
      "pmid": "31002283",
      "year": "2019",
      "title": "Heat therapy vs. supervised exercise therapy for peripheral arterial disease: a 12-wk randomized, controlled trial.",
      "doi": "10.1152/ajpheart.00151.2019",
      "url": "https://pubmed.ncbi.nlm.nih.gov/31002283/",
      "interpretation": "PAD heat-plus-calisthenics versus exercise comparison shows functional improvement without clear between-arm superiority."
    },
    {
      "pmid": "32192678",
      "year": "2020",
      "title": "TREAT AF (Transcutaneous Electrical Vagus Nerve Stimulation to Suppress Atrial Fibrillation): A Randomized Clinical Trial.",
      "doi": "10.1016/j.jacep.2019.11.008",
      "url": "https://pubmed.ncbi.nlm.nih.gov/32192678/",
      "interpretation": "Named home auricular device with active sensory comparator reduces objective AF burden in a defined disease trial."
    },
    {
      "pmid": "35785965",
      "year": "2022",
      "title": "Effects of regular sauna bathing in conjunction with exercise on cardiovascular function: a multi-arm, randomized controlled trial.",
      "doi": "10.1152/ajpregu.00076.2022",
      "url": "https://pubmed.ncbi.nlm.nih.gov/35785965/",
      "interpretation": "Exercise-plus-sauna randomized trial adds BP and estimated-fitness benefits over exercise."
    },
    {
      "pmid": "37650138",
      "year": "2023",
      "title": "Finnish sauna bathing and vascular health of adults with coronary artery disease: a randomized controlled trial.",
      "doi": "10.1152/japplphysiol.00322.2023",
      "url": "https://pubmed.ncbi.nlm.nih.gov/37650138/",
      "interpretation": "CAD randomized exposure achieves acclimation without the predicted vascular/BP benefit."
    },
    {
      "pmid": "38546822",
      "year": "2024",
      "title": "Transcutaneous vagal nerve stimulation for treating gastrointestinal symptoms in individuals with diabetes: a randomised, double-blind, sham-controlled, multicentre trial.",
      "doi": "10.1007/s00125-024-06129-0",
      "url": "https://pubmed.ncbi.nlm.nih.gov/38546822/",
      "interpretation": "Defined cervical-stimulation diabetes trial is clinically symptom-null despite broader vagal-treatment hypotheses."
    },
    {
      "pmid": "39680406",
      "year": "2024",
      "title": "Transcutaneous Auricular Vagus Nerve Stimulation for Chronic Insomnia Disorder: A Randomized Clinical Trial.",
      "doi": "10.1001/jamanetworkopen.2024.51217",
      "url": "https://pubmed.ncbi.nlm.nih.gov/39680406/",
      "interpretation": "Specific sham-controlled auricular insomnia trial has clinically meaningful symptom effects."
    },
    {
      "pmid": "40498100",
      "year": "2025",
      "title": "Cold- and hot-water immersion are not more effective than placebo for the recovery of physical performance and training adaptations in national level soccer players.",
      "doi": "10.1007/s00421-025-05835-w",
      "url": "https://pubmed.ncbi.nlm.nih.gov/40498100/",
      "interpretation": "Cold/hot athlete recovery does not exceed placebo in measured acute and longer-term performance outcomes."
    },
    {
      "pmid": "40719540",
      "year": "2025",
      "title": "Post-exercise hot water immersion enhances haemodynamic and vascular benefits of exercise without further improving cardiorespiratory fitness, glucose, lipids or inflammation.",
      "doi": "10.1113/JP288873",
      "url": "https://pubmed.ncbi.nlm.nih.gov/40719540/",
      "interpretation": "Added hot-water exposure improves selected vascular/BP measures beyond exercise but not all cardiometabolic endpoints."
    },
    {
      "pmid": "41455014",
      "year": "2025",
      "title": "Transauricular Vagus Nerve Stimulation in Acute Ischaemic Stroke Requiring Mechanical Thrombectomy: Sham-Controlled, Randomised Device Trial.",
      "doi": "10.1007/s12975-025-01404-7",
      "url": "https://pubmed.ncbi.nlm.nih.gov/41455014/",
      "interpretation": "Hyperacute-stroke device trial changes molecular/autonomic measures without its primaryBP-variability benefit."
    },
    {
      "pmid": "41831305",
      "year": "2026",
      "title": "Effects of Sauna bathing on Exercise Capacity and Muscle Function in HFpEF.",
      "doi": "10.1093/ejhf/xuag082",
      "url": "https://pubmed.ncbi.nlm.nih.gov/41831305/",
      "interpretation": "Open HFpEF sauna pilot shows function gains and partial loss after withdrawal, with a controlled trial described as planned."
    },
    {
      "pmid": "42113470",
      "year": "2026",
      "title": "Acute effects of passive heat exposure on vascular function and exercise capacity in patients with chronic kidney disease.",
      "doi": "10.1152/ajpheart.00020.2026",
      "url": "https://pubmed.ncbi.nlm.nih.gov/42113470/",
      "interpretation": "Acute CKD controlled sauna pilot shows selected function and vascular positives with limited horizon."
    }
  ],
  "gaps": [
    "Independent clinical-event causal evidence for habitual sauna, with repeated exposure and settings beyond the Finnish cohort family.",
    "Whether BP/vascular/autonomic changes mediate events rather than simply coexist with exposure.",
    "Sauna-alone versus exercise-plus-sauna and modality equivalence without substituting water immersion, infrared Waon or local heating.",
    "Durable cold-health endpoints and indication-specific recovery/adaptation tradeoffs, with measured expectancy and adherence.",
    "Exact consumer-device identity and indication-specific active-sham evidence; implanted, cervical and auricular stimulation cannot be interchanged by label.",
    "Longer-term benefit-harm data in predefined disease and medication strata without converting supervised short tolerability into universal safety."
  ],
  "decisive_experiment": "A multicenter randomized pragmatic sauna-plus-usual-care versus matched usual-care/time-contact study, or a validated independent access/withdrawal natural experiment, with adjudicated cardiovascular hospitalization, infarction, stroke and cardiovascular death over prespecified follow-up, stratifying baseline disease and exercise before outcomes."
}