{ "abstract": "Rationale\n\nEarly prediction of lung function decline remains challenging in idiopathic pulmonary fibrosis (IPF) and fibrotic interstitial lung diseases (ILDs). We evaluated whether oxygen desaturation during the 6-min walk test (6MWT) predicts forced vital capacity (FVC) decline and long-term outcomes.Methods\n\nWe analysed data from two independent cohorts: the nationwide Japanese Idiopathic Interstitial Pneumonias (JIPS) Registry and an external IPF cohort (K-Junko Study). Hazard ratios (HRs) were estimated for each 6MWT parameter to identify variables associated with FVC decline and to determine optimal thresholds. Sensitivity analyses were conducted using Fine-Gray models. The performance of the predictive model was assessed using calibration plots and the concordance index (C-index).Results\n\nIn the JIPS IPF (n=457) and K-Junko IPF (n=318) cohorts, a peripheral oxygen saturation (S pO₂ ) change of ≤-6 percentage points during the 6MWT independently predicted a decline in FVC of ≥5 percentage points in both cohorts (JIPS HR 1.292; K-Junko HR 1.480). Moreover, S pO₂ change during the 6MWT was significantly associated with FVC change in the subsequent year, and this association persisted over 5 consecutive years in JIPS IPF cohort. The nomogram demonstrated moderate discrimination (C-index: 0.619 (training) and 0.632 (validation)) and fair calibration. A composite profile meeting all three criteria (FVC ≥80%, S pO₂ change >-6 percentage points, 6-min walk distance (6MWD) ≥420 m) identified patients with favourable transplant-free survival. In the JIPS non-IPF fibrotic ILD cohort (n=387), S pO₂ change remained the sole independent predictor of an FVC decline of ≥5 percentage points (HR 1.350).Conclusion\n\nS pO₂ change during the 6MWT predicts FVC decline and outcomes across fibrotic ILD; its incorporation into routine assessment may enable earlier risk stratification and facilitate timely intervention.", "abstract_shown": true, "affiliations": [ "Department of Respiratory Medicine, Kanagawa Cardiovascular and Respiratory Center, Yokohama, Japan.", "Respiratory Disease Center, Tokyo General Hospital, Tokyo, Japan.", "Department of Respiratory Medicine and Allergology, Sapporo Medical University School of Medicine, Sapporo, Japan.", "Department of Biostatistics, Yokohama City University School of Medicine, Yokohama, Japan.", "Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Hamamatsu, Japan.", "Department of Respirology, Graduate School of Medicine, Chiba University, Chiba, Japan.", "Department of Respiratory Medicine, Kobe City Medical Center West Hospital, Kobe, Japan.", "Department of Respiratory Medicine, Toho University Omori Medical Center, Tokyo, Japan.", "Division of Respirology, Neurology, and Rheumatology, Department of Internal Medicine, Kurume University School of Medicine, Kurume, Japan.", "Department of Respiratory Medicine, Allergy and Clinical Immunology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan.", "Division of Pulmonary Medicine, Department of Medicine, Jichi Medical University, Shimotsuke, Japan.", "Department of Respiratory Medicine, National Hospital Organization Himeji Medical Center, Himeji, Japan.", "Department of Respiratory Medicine, National Hospital Organization Matsue Medical Center, Matsue, Japan.", "Department of Respiratory Medicine, Nagoya University Graduate School of Medicine, Nagoya, Japan.", "Department of Respiratory Medicine, Gunma University Graduate School of Medicine, Maebashi, Japan.", "Department of Respiratory Medicine and Allergology, Kindai University Faculty of Medicine, Sakai, Japan.", "Division of Respiratory Medicine, Department of Internal Medicine, Shiga University of Medical Science, Otsu, Japan.", "Department of Respiratory Medicine, University of Occupational and Environmental Health, Japan, Kitakyusyu, Japan.", "Department of Respiratory Medicine, NTT Medical Center Tokyo, Tokyo, Japan.", "Department of Respiratory Medicine, Saitama Red Cross Hospital, Saitama, Japan.", "Respiratiory Medicine, Seirei Hamamatsu General Hospital, Hamamatsu, Japan.", "Department of Advanced Medicine for Respiratory Failure, Graduate School of Medicine, Kyoto University, Kyoto, Japan.", "Department of Respiratory Medicine, Okinawa Chubu Hospital, Uruma, Japan.", "Department of Respiratory Medicine, Kumamoto University Hospital, Kumamoto, Japan.", "Department of Respiratory Medicine, National Hospital Organization Tokyo Medical Center, Tokyo, Japan.", "Department of Pulmonary Medicine, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima, Japan.", "Department of Respiratory Medicine, Nagasaki University Hospital, Nagasaki, Japan.", "National Hospital Organization Tokyo National Hospital, Kiyose, Japan.", "Tohoku University, Sendai, Japan.", "Department of Respiratory Medicine, Saitama Medical University International Medical Center, Hidaka, Japan." ], "article_type": "research article", "arxiv": null, "author_total": 35, "authors": [ { "affs": [ 0 ], "name": "Takashi Ogura" }, { "affs": [ 0 ], "name": "Ryo Okuda", "orcid": "0000-0001-8691-7773" }, { "affs": [ 1 ], "name": "Ichiro Kuwahira", "orcid": "0000-0002-8147-8983" }, { "affs": [ 2 ], "name": "Hirotaka Nishikiori", "orcid": "0000-0002-0573-9344" }, { "affs": [ 2 ], "name": "Hirofumi Chiba" }, { "affs": [ 3 ], "name": "Yuriko Takeda" }, { "affs": [ 4 ], "name": "Takafumi Suda" }, { "affs": [ 4 ], "name": "Tomoyuki Fujisawa", "orcid": "0000-0002-8809-1781" }, { "affs": [ 5 ], "name": "Mitsuhiro Abe" }, { "affs": [ 6 ], "name": "Hiromi Tomioka" }, { "affs": [ 7 ], "name": "Susumu Sakamoto" }, { "affs": [ 8 ], "name": "Yoshiaki Zaizen" }, { "affs": [ 9 ], "name": "Hirotsugu Ohkubo", "orcid": "0000-0002-8538-1150" }, { "affs": [ 10 ], "name": "Hiroyoshi Yamauchi" }, { "affs": [ 11 ], "name": "Tetsuji Kawamura" }, { "affs": [ 12 ], "name": "Masahiro Kimura" }, { "affs": [ 13 ], "name": "Koji Sakamoto", "orcid": "0000-0002-1794-576X" }, { "affs": [ 14 ], "name": "Yasuhiko Koga", "orcid": "0000-0002-4974-9026" }, { "affs": [ 15 ], "name": "Osamu Nishiyama" }, { "affs": [ 16 ], "name": "Hiroaki Nakagawa" }, { "affs": [ 17 ], "name": "Kazuhiro Yatera", "orcid": "0000-0002-2955-4432" }, { "affs": [ 18 ], "name": "Kazuhiro Usui", "orcid": "0000-0002-4492-9327" }, { "affs": [ 19 ], "name": "Hidekazu Matsushima" }, { "affs": [ 20 ], "name": "Dai Hashimoto" }, { "affs": [ 21 ], "name": "Tomohiro Handa" }, { "affs": [ 22 ], "name": "Tomoo Kishaba" }, { "affs": [ 23 ], "name": "Hidenori Ichiyasu" }, { "affs": [ 24 ], "name": "Yoshitaka Oyamada" }, { "affs": [ 25 ], "name": "Toshiaki Matsuda" }, { "affs": [ 26 ], "name": "Hiroshi Ishimoto" }, { "affs": [ 27 ], "name": "Osamu Narumoto" }, { "affs": [ 28 ], "name": "Toshihiro Nukiwa" }, { "affs": [ 29 ], "name": "Kunihiko Kobayashi" }, { "name": "JIPS Registry collaborators" }, { "name": "JIPS Registry collaborators" } ], "bibtex": "https://research.draconitic.com/paper/c5zs727h92xfe.bib", "cited_by": 0, "doi": "10.1183/23120541.00691-2026", "fulltext_url": "https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13725836/?tool=EBI", "id": "c5zs727h92xfe", "issns": [ "2312-0541" ], "landing_url": "https://europepmc.org/article/PMC/PMC13725836", "language": "eng", "licence": "CC-BY-NC", "licence_label": "CC BY-NC", "licence_source": "article", "licence_url": "https://creativecommons.org/licenses/by-nc/4.0/", "metadata_licence": null, "native_subjects": [ [ "heading", "13" ], [ "heading", "Interstitial Lung Diseases" ], [ "heading", "Original Research Article" ], [ "openalex", "2740|Interstitial Lung Diseases and Idiopathic Pulmonary Fibrosis" ] ], "openalex": "W7170188479", "pdf_url": "https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13725836/pdf/?tool=EBI", "pmcid": "PMC13725836", "pmid": "42974372", "published": "2026-11-01", "publisher": "European Respiratory Society", "ris": "https://research.draconitic.com/paper/c5zs727h92xfe.ris", "sources": [ { "first_seen": "2026-11-03T15:20:51Z", "native_id": "PMC:PMC13725836", "source": "europepmc", "url": "https://europepmc.org/article/PMC/PMC13725836" }, { "first_seen": "2026-11-04T15:20:47Z", "native_id": "MED:42974372", "source": "europepmc", "url": "https://europepmc.org/article/MED/42974372" }, { "first_seen": "2026-11-05T12:22:17Z", "native_id": "PMC13725836", "source": "pmc", "url": "https://doi.org/10.1183/23120541.00691-2026" } ], "subjects": [ { "field": "medicine", "origin": "openalex:2740|Interstitial Lung Diseases and Idiopathic Pulmonary Fibrosis", "subfield": "general" } ], "title": "6-min walk test reveals early physiological impairment in fibrotic interstitial lung diseases", "title_text": "6-min walk test reveals early physiological impairment in fibrotic interstitial lung diseases", "type": "peer-reviewed", "updated_at": "2026-11-06T12:21:56Z", "url": "https://research.draconitic.com/paper/c5zs727h92xfe", "venue": "ERJ open research", "versions": [] }