{
  "abstract": "Amyotrophic lateral sclerosis (ALS) exhibit heterogeneous functional decline, potentially influenced by systemic metabolic reserve. We investigate whether circulating insulin-like growth factor 1 (IGF-1) is associated with subsequent functional change in ALS. Serum IGF-1 was measured in 37 participants with ALS and 25 healthy controls. Baseline levels were compared between groups, and across disease-duration defined progression categories. Lagged regression assessed whether prior visit IGF-1 level predicted change in Revised ALS Functional Rating Scale (ALSFRS-R) on the next visit, adjusting for inter-visit interval, body mass index, age and sex. Mixed-effects and sensitivity analyses assessed robustness. Baseline IGF-1 did not differ significantly between controls and ALS (mean + SD: 107.3 + 54.3 vs 132.2 + 68.3 ng/mL, p = 0.12), or across progression categories (F(2, 34) = 0.13, p = 0.88). Across 48 intervals from 23 ALS participants, each 1-SD higher IGF-1 from prior visit was associated with 1.40-point less subsequent {Delta}ALSFRS-R decline (95% CI: 0.03 to 2.77, p = 0.045). Generalised estimating equations yielded a similar association ({beta} = 1.50, p = 0.030), whereas small-cluster robust inference showed wider uncertainty (p = 0.084). Repeated IGF-1 showed an intraclass correlation coefficient of 0.69, and the lagged association remained positive in all 23 leave-one-participant-out analyses. The IGF-1-by-time interaction was not significant in a random-slope mixed model (p =0.254). Higher circulating IGF-1 may reflect systemic trophic-metabolic reserve associated with short-term functional preservation in ALS, but limited precision precludes definitive prognostic or causal conclusions.",
  "abstract_shown": true,
  "affiliations": [
    "MND Research Centre, Faculty of Medicine, Health and Human Sciences, Macquarie University"
  ],
  "article_type": "PUBLISHAHEADOFPRINT",
  "arxiv": null,
  "author_total": 7,
  "authors": [
    {
      "name": "C. K. Lim"
    },
    {
      "name": "M. Brocardo"
    },
    {
      "name": "J. Hunter"
    },
    {
      "name": "J. A. Heads"
    },
    {
      "name": "D. B. Rowe"
    },
    {
      "name": "S. Furlong"
    },
    {
      "affs": [
        0
      ],
      "name": "J. D. Atkin"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/ax46k33n3479c.bib",
  "cited_by": 0,
  "doi": "10.64898/2026.11.05.26366903",
  "fulltext_url": "https://www.medrxiv.org/content/10.64898/2026.11.05.26366903v1.full",
  "id": "ax46k33n3479c",
  "issns": [],
  "landing_url": "https://www.medrxiv.org/content/10.64898/2026.11.05.26366903v1",
  "language": null,
  "licence": "CC-BY-NC-ND",
  "licence_label": "CC BY-NC-ND",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by-nc-nd/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "medrxiv",
      "neurology"
    ]
  ],
  "openalex": null,
  "pdf_url": "https://www.medrxiv.org/content/10.64898/2026.11.05.26366903v1.full.pdf",
  "pmcid": null,
  "pmid": null,
  "published": "2026-11-05",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/ax46k33n3479c.ris",
  "sources": [
    {
      "first_seen": "2026-11-07T00:20:58Z",
      "native_id": "10.64898/2026.11.05.26366903",
      "source": "medrxiv",
      "url": "https://www.medrxiv.org/content/10.64898/2026.11.05.26366903v1"
    }
  ],
  "subjects": [
    {
      "field": "medicine",
      "origin": "medrxiv:neurology",
      "subfield": "neurology"
    }
  ],
  "title": "Circulating insulin-like growth factor 1 (IGF-1) and short-term functional change in amyotrophic lateral sclerosis (ALS): exploratory evidence for systemic trophic-metabolic reserve.",
  "title_text": "Circulating insulin-like growth factor 1 (IGF-1) and short-term functional change in amyotrophic lateral sclerosis (ALS): exploratory evidence for systemic trophic-metabolic reserve.",
  "type": "preprint",
  "updated_at": "2026-11-08T00:20:58Z",
  "url": "https://research.draconitic.com/paper/ax46k33n3479c",
  "venue": "medRxiv",
  "versions": []
}