Statistics — type 1 diabetes¶
Last curated: 2026-08-30
Global burden¶
| Measure | Estimate | Year/population/method | Source |
|---|---|---|---|
| People living with T1D | 8.4M (95% UI 8.1–8.8) | 2021 global model | PMID 36113507 |
| New diagnoses | ~0.5M | 2021 global model | PMID 36113507 |
| Deaths undiagnosed within 12 months of symptoms | ~35,000 | 2021 model | PMID 36113507 |
| Projected prevalence | 13.5–17.4M | 2040 scenarios | PMID 36113507 |
| Projected increase | 60–107% | 2021–2040 | PMID 36113507 |
| Prevalent cases aged 20–59 | 64% | 2021 model | PMID 36113507 |
| Median onset age | 39 years | modeled global distribution | PMID 36113507 |
Diagnosis and natural history¶
| Measure | Estimate | Population/method | Source |
|---|---|---|---|
| Multiple-antibody progression at 10 years | 69.7% (95% CI 65.1–74.3) | pooled prospective children | PMID 23780460 |
| Multiple-antibody progression at 15 years | 84% | pooled prospective children | PMID 23780460 |
| Single-antibody progression at 10 years | 14.5% | pooled prospective children | PMID 23780460 |
| No-antibody diabetes by age 15 | 0.4% | pooled prospective children | PMID 23780460 |
| Fr1da presymptomatic yield | 0.31% (95% CI 0.27–0.35) | 90,632 Bavarian children | PMID 31990315 |
| Pediatric DKA at diagnosis | 41.9% (95% CI 39.7–44.0) | 233 studies; 380,191 children; 58 countries | PMID 42303108 |
| Country DKA range | 15.6–78.5% | meta-analysis country estimates | PMID 42303108 |
Risk refinement and monitored diagnosis¶
| Measure | Estimate | Population/method | Source |
|---|---|---|---|
| IA-2A and progression, single-antibody state | 5.3-fold higher 5-year risk | 4,577 antibody-positive TrialNet relatives | PMID 40016443 |
| IA-2A and progression, stage 1 | 2.2-fold higher 5-year risk | TrialNet relatives | PMID 40016443 |
| IA-2A and progression, stage 2 | 1.3-fold higher 5-year risk | TrialNet relatives | PMID 40016443 |
| Five-year risk across antibody-titer strata | 6–75% | 1,604 confirmed-positive children | PMID 34758977 |
| Screen at age 10 predicting diabetes by 18 | sensitivity 90% (95% CI 86–95); PPV 66% | genetically/familially enriched adolescents | PMID 36681087 |
| Screens at ages 10 and 14 | sensitivity 93%; PPV 55% | same harmonized cohorts | PMID 36681087 |
| HbA1c ≥5.7%, one-year progression with one antibody | children 38%; adults 13% | 5,024 antibody-positive TrialNet relatives | PMID 42090204 |
| TEDDY DKA under surveillance | 6.1% (23/379) | prospectively monitored children | PMID 35043162 |
| TrialNet single-center DKA among progressors | 0/51 | 4,046 relatives; median 9.9-year follow-up | PMID 40439773 |
| Three-month secretion-loss marker | specificity 95% (95% CI 86–100); sensitivity 19% (8–30) | TN-10 metabolic reanalysis | PMID 39560746 |
Screening economics, assays, and burden¶
| Measure | Estimate | Context | Source |
|---|---|---|---|
| ASK research-program cost per case detected | $4,700 | Colorado model | PMID 32327420 |
| ASK routine-care scenario cost per case detected | $14,000 | Colorado model | PMID 32327420 |
| Scenario needed for conventional cost-effectiveness | 20% DKA reduction plus sustained 0.1-point HbA1c benefit | model assumption, not observed effect | PMID 32327420 |
| Initial parental anxiety after positive screen | 46.1±11.2 | 280 ASK families; clinical cutoff 40 | PMID 37673098 |
| Initial accurate understanding of increased risk | 48.9% | ASK follow-up | PMID 37673098 |
| Harmonized IA-2A performance | >99% specificity; 64% sensitivity | assay-harmonization program | PMID 20444913 |
| GADA retest discordance | 15.4% to 2.7% | TEDDY samples before vs after harmonization | PMID 20444913 |
Treatment effects¶
| Intervention/outcome | Estimate | Design | Source |
|---|---|---|---|
| DCCT retinopathy onset | 76% reduction | RCT | PMID 8366922 |
| DCCT microalbuminuria | 39% reduction | RCT | PMID 8366922 |
| DCCT clinical neuropathy | 60% reduction | RCT | PMID 8366922 |
| CGM HbA1c difference, injection users | −0.6% (95% CI −0.8 to −0.3) | 24-week RCT | PMID 28118453 |
| iDCL TIR difference | +11 points (95% CI 9–14) | 6-month RCT | PMID 31618560 |
| Very-young-child closed-loop TIR | +8.7 points (95% CI 7.4–9.9) | crossover RCT | PMID 35045227 |
| Bionic pancreas HbA1c | −0.5% (95% CI −0.6 to −0.3) | 13-week adult RCT | PMID 36173236 |
| Teplizumab time to stage 3 | 48.4 vs 24.4 months | 76-person RCT | PMID 31180194 |
| Teplizumab stage-3 hazard | HR 0.41 (95% CI 0.22–0.78) | RCT | PMID 31180194 |
| Verapamil C-peptide | 30% higher at 52 weeks | pediatric RCT | PMID 36826844 |
| Zimislecel insulin independence | 10/12 full-dose recipients | phase 1–2 uncontrolled | PMID 40544428 |
| HCL meta-analysis TIR | +10.87 points (95% CI 9.38–12.37) | 22 trials lasting 12–96 weeks | PMID 37759290 |
| Youth AID meta-analysis TIR | +11.5 points (95% CI 9.3–13.7) | randomized trials | PMID 40920375 |
| Youth AID nighttime TIR | +19.7 points (95% CI 17.0–22.4) | randomized trials | PMID 40920375 |
| Real-world AID TIR | +11.61 points (95% CI 10.47–12.76) | before–after meta-analysis; 101,704 users | PMID 38888056 |
| HARPdoc vs BGAT severe-event rate | IRR 1.25 (95% CI 0.51–3.09) at 12 months | active-comparator RCT | PMID 35484106 |
| HypoCOMPaSS severe events | 8.9 to 0.4/person-year at 24 months | intervention cohort follow-up | PMID 29661916 |
| Immunotherapy pooled C-peptide | SMD 0.221 (95% CI 0.069–0.373) | 19 trials; 1,852 participants | PMID 41267047 |
| Immunotherapy pooled HbA1c | SMD 0.033 (95% CI −0.070 to 0.136) | same meta-analysis | PMID 41267047 |
| Stage-1 abatacept, high-secretor subgroup | HR 0.46 (95% CI 0.25–0.84) | post hoc TrialNet reanalysis | PMID 41237315 |
Cell-replacement outcomes and harms¶
| Outcome | Estimate | Population/design | Source |
|---|---|---|---|
| Islet-transplant composite at 1 year | 87.5% | 48-person phase 3; HbA1c <7% without severe hypoglycemia | PMID 27208344 |
| Islet-transplant composite at 2 years | 71% | same cohort | PMID 27208344 |
| Bleeding requiring transfusion | 5/48 (10.4%) | 75 portal-infusion procedures | PMID 27208344 |
| Ten-year insulin independence | 28% (95% CI 13–45) | 28-person French cohort | PMID 31615852 |
| Ten-year graft function | 78% (95% CI 57–89) | same cohort | PMID 31615852 |
| TRIMECO modified β-score ≥6 | 64% (95% CI 43–82) vs 0% (0–15) | randomized islets vs intensive insulin at 6 months | PMID 29776895 |
| TRIMECO portal-infusion bleeding | 4/55 infusions (7%) | randomized trial/transplant procedures | PMID 29776895 |
| CITR 3-year insulin independence | 27% to 44% | 1999–2002 vs 2007–2010 eras | PMID 22723582 |
Outcomes and inequity¶
| Measure | Estimate | Population/year | Source |
|---|---|---|---|
| Life-years lost at age 20, men | 11.1 years | Scotland 2008–2010 | PMID 25562264 |
| Life-years lost at age 20, women | 12.9 years | Scotland 2008–2010 | PMID 25562264 |
| Remaining life expectancy after diagnosis age 10 | 13 years | modeled low-income setting, 2021 | PMID 36113507 |
| Remaining life expectancy after diagnosis age 10 | 65 years | modeled high-income setting, 2021 | PMID 36113507 |
| ADA HbA1c goal attainment, youth | 17% | T1D Exchange 2016–2018 | PMID 30657336 |
| ADA HbA1c goal attainment, adults | 21% | T1D Exchange 2016–2018 | PMID 30657336 |
| Mean HbA1c ages 15–18 | 9.3% | T1D Exchange 2016–2018 | PMID 30657336 |
| Diabetes-distress prevalence | 38.9% | global systematic review/meta-analysis; heterogeneous definitions | PMID 42486409 |
| DEPS-R positive screen | 13.2% (95% CI 8.8–17.5) | 228 people with T1D in Hong Kong | PMID 37259043 |
| Interview-defined eating disorder | 4.4% (95% CI 2.1–7.9) | same study | PMID 37259043 |
| Impaired awareness in UK adult cohort | 21% | 782 adults; 89% using CGM | PMID 40386839 |
| Recent severe hypoglycemia in UK adult cohort | 5.3% | same cross-sectional cohort | PMID 40386839 |
| Severe-event odds per 1-point glucose CV | OR 1.14 | same cohort | PMID 40386839 |
Known conflicts and caveats¶
- Global counts are modeled, not complete enumeration (PMID 36113507).
- GBD all-diabetes totals must not be relabeled as T1D-specific (PMID 37356446).
- Birth-cohort progression estimates are strongest for genetically enriched children, not adult-onset disease.
- Trial effects are comparator-, device-, and support-dependent.
- Life expectancy is era- and health-system-specific; conflicting estimates should remain side by side.
- Registry goal attainment describes participating clinics, not a national probability sample.
- Screening cost-effectiveness rows are model outputs that depend on assumed DKA and long-term HbA1c effects.
- Subgroup hazard ratios, particularly stage-1 abatacept high secretors, are hypothesis-generating until prospectively replicated.
- Transplant success estimates come from highly selected people with severe hypoglycemia and must be paired with procedural, renal, infection, and immunosuppression outcomes.
- Psychosocial prevalence depends strongly on instrument, threshold, language, and sampling frame.