Insulin Resistance & Multiple Sclerosis

Prevalence trajectories in the USA and United Kingdom, 1975–2022. MS is shown per 100,000 population (right axis) as absolute prevalence remains below 1% — but the trend is consistent and well-documented. Both conditions have risen in parallel over 50 years, and a 2024 systematic review and meta-analysis (18 datasets) confirms that HOMA-IR is significantly elevated in MS patients compared to healthy controls, establishing a clinically meaningful association between insulin resistance and MS burden and progression.

United States

USA — Insulin Resistance vs MS

1975 – 2022 | IR: % population · MS: per 100,000

Insulin Resistance (%)

MS Prevalence (per 100k)

United Kingdom

UK — Insulin Resistance vs MS

1975 – 2022 | IR: % population · MS: per 100,000

Insulin Resistance (%)

MS Prevalence (per 100k)

r = 0.96

USA
IR ↔ MS

r = 0.97

UK
IR ↔ MS

~310/100k

USA MS prevalence
current estimate

~240/100k

UK MS prevalence
current estimate

Important context on the MS trend: MS prevalence has risen substantially in both countries over 50 years — but this rise is partly explained by improved survival (people with MS living longer due to better treatment) and better diagnostic recognition, rather than purely an increase in new cases. The incidence of new MS diagnoses has also risen, particularly in women (now 2.5–3× more common in women than men), which is itself unexplained. The parallel rise with insulin resistance is striking and the mechanistic research is compelling, but MS remains a complex autoimmune condition with multiple contributing factors including Epstein-Barr virus, vitamin D deficiency, latitude, genetics, and smoking.

The mechanistic evidence is now substantial: A 2024 systematic review and meta-analysis (Sepidarkish et al., Metabolic Brain Disease, 18 datasets, 2012–2022) found HOMA-IR scores are significantly elevated in MS patients vs healthy controls (SMD = 0.78). MS patients show postprandial hyperinsulinaemia and reduced insulin sensitivity independent of obesity or inflammation alone. Insulin plays a critical role in cerebral glucose metabolism, myelin maintenance, and neuroinflammatory regulation. Hyperinsulinaemia promotes the same pro-inflammatory cytokines (IL-6, TNF-α) that drive demyelination. A 2023 cross-sectional study confirmed insulin resistance is directly associated with greater cognitive impairment in relapsing-remitting MS. The relationship appears bidirectional: MS-driven inflammation may worsen insulin resistance, which in turn accelerates neurodegeneration.

What is r? Pearson correlation coefficient. 0 = no relationship | 1.0 = perfect parallel rise. Above 0.7 = strong. These are population-level — association, not cause. Note: MS prevalence data shown here reflects both new incidence and improved survival; r values reflect the parallel trend, not proof of a single causal mechanism.

Data sources

MS USA — prevalence trend: Wallin et al. Neurology 2019 — validated algorithm across private, military & public claims data; ~309/100k (2010), ~1 million people. Dilokthornsakul et al. PMC 2016 — commercially insured population 2008–2012: 149/100k. JAMA Neurology 2023 — 10-year cumulative prevalence by race/ethnicity/geography. Current estimate: ~310/100k (~1 million people). Estimated 1975 back-projection from historical survey data and incidence records: ~60–80/100k.
https://pmc.ncbi.nlm.nih.gov/articles/PMC6442006/
https://jamanetwork.com/journals/jamaneurology/fullarticle/2805038
https://pmc.ncbi.nlm.nih.gov/articles/PMC4799713/

MS UK — prevalence trend: Mackenzie et al. BMJ Open 2014 — GPRD 1990–2010: prevalence rose 2.4%/year, reaching ~200/100k by 2010. PHE/MS Society 2019: 130,000 (1 in 500). MS Society 2024: >150,000 (~240/100k). MS Trust prevalence data briefing 2020. Pre-1990 estimates from earlier UK epidemiological studies and incidence data.
https://pubmed.ncbi.nlm.nih.gov/24052635/
https://www.gov.uk/government/publications/multiple-sclerosis-prevalence-incidence-and-smoking-status/multiple-sclerosis-prevalence-incidence-and-smoking-status-data-briefing
https://www.mssociety.org.uk/what-we-do/our-work/our-evidence/ms-in-the-uk

IR–MS association — clinical evidence: Sepidarkish et al. Metabolic Brain Disease 2024 — systematic review & meta-analysis, 18 datasets 2012–2022: HOMA-IR significantly elevated in MS vs controls (SMD=0.78). Ayromlou et al. Journal of Neuroendocrinology 2023: IR associated with cognitive dysfunction in RRMS. Maric et al. MS & Related Disorders 2020: hyperinsulinaemia in newly diagnosed MS patients. Soliman et al. 2020: IR and metabolic syndrome significantly more prevalent in MS patients (46% vs 0% IR, p<0.001).
https://pubmed.ncbi.nlm.nih.gov/38767742/
https://onlinelibrary.wiley.com/doi/10.1111/jne.13288
https://ejnpn.springeropen.com/articles/10.1186/s41983-020-0155-y

Insulin Resistance USA: NHANES III 1988–94; NHANES 1999–2018 (Hirode & Wong, JAMA 2020); Frontiers meta-analysis 2025.
https://pmc.ncbi.nlm.nih.gov/articles/PMC11601873/
https://pmc.ncbi.nlm.nih.gov/articles/PMC12411212/

Insulin Resistance UK: NHS Health Survey England 2003–2021; GBD 2019 metabolic risk data; Diabetes UK.
https://digital.nhs.uk/data-and-information/publications/statistical/health-survey-for-england
https://www.diabetesuk.org/professionals/position-statements-reports/statistics/