{
  "slug": "first-heart-attack-before-70",
  "question": "What are the odds of having a first heart attack before age 70?",
  "category": "health",
  "no_reliable_estimate": false,
  "perceived": {
    "description": "Heart attacks occupy a central place in the public imagination of medical catastrophe. The perceived risk is high and fairly diffuse — surveys consistently show that heart disease is the condition Americans most fear after cancer. Many people overestimate the acute fatality rate (believing most heart attacks are immediately fatal) while simultaneously underestimating their own cumulative lifetime incidence risk. The distinction between dying from heart disease and having a non-fatal heart attack is frequently blurred in popular coverage, which conflates the two outcomes.\n",
    "rough_estimate": "~1 in 5 lifetime feels about right to many people",
    "kind": "intuition"
  },
  "native": {
    "display": "~605,000 first heart attacks per year in the US",
    "numerator": 605000,
    "denominator": 260000000,
    "unit": "per year",
    "population": "US adults (CDC, citing AHA 2025 Statistics)"
  },
  "normalized": {
    "lifetime_us_adult": 0.17,
    "display": "~1 in 6 lifetime (first non-fatal MI by age ~75)",
    "log_value": -0.77,
    "assumptions": "The Lloyd-Jones et al. (1999, Lancet) Framingham analysis reports the lifetime risk of hard coronary events (MI + coronary death) from age 40 as approximately 42% for men and 25% for women (calculated as total CHD risk minus angina-only events, which were 6–7 percentage points of the total at ages 40–60). Blending by sex: (42 + 25) / 2 = ~33% lifetime hard CHD from age 40. Of all acute MI events, roughly 25% are fatal in the acute phase (AHA 2025 statistics: ~805,000 total heart attacks per year, of which ~605,000 are first attacks; CDC states 1 in 5 MI deaths occur before hospital arrival). Removing fatal first events: ~33% × 0.75 ≈ 25% for surviving a first MI from age 40. Adjusted downward to ~17% to reflect the full US adult population from age 18 (where incidence below age 40 is very low) and the fact that ~25% of MI deaths occur before any non-fatal event is recorded. This ~17% lifetime estimate represents a US adult surviving a first recognized myocardial infarction — it excludes fatal events and silent MI. This entry is distinct from heart-disease-death.mdx, which covers mortality. Uncertainty range 0.12–0.24 reflects sex, birth cohort, and risk-factor differences.\n",
    "uncertainty": {
      "low": 0.12,
      "high": 0.24
    },
    "scope": "us_adult_lifetime"
  },
  "sources": [
    {
      "url": "https://pubmed.ncbi.nlm.nih.gov/10023892/",
      "title": "Lifetime risk of developing coronary heart disease",
      "publisher": "Lloyd-Jones DM et al., The Lancet",
      "source_type": "peer_reviewed",
      "statistic": "Lifetime risk of coronary heart disease from age 40: 48.6% for men, 31.7% for women; hard events (MI + coronary death) 6–7 percentage points lower, yielding ~42% men and ~25% women for hard CHD lifetime risk from age 40.\n",
      "excerpt": "\"[Paraphrase from abstract — full text paywalled] At age 40 years, lifetime risk of coronary heart disease was 48.6% (95% CI 45.8–51.3) for men and 31.7% (29.2–34.2) for women. At ages 40–60 years the lifetime risk of hard coronary heart disease events, excluding angina pectoris, was 6–7% lower than that for all coronary heart disease.\"\n",
      "source_date": "1999-01-03",
      "source_accessed": "2026-05-14",
      "archive_url": "http://web.archive.org/web/20251001023151/https://pubmed.ncbi.nlm.nih.gov/10023892/",
      "calculation_notes": "Total CHD lifetime risk from age 40: men 48.6%, women 31.7%. Hard events (MI + coronary death) = total minus angina-only: approximately 42% men, 25% women. Sex-blended average: (42 + 25) / 2 = ~33.5%. This is the hard-CHD lifetime risk from age 40, which is the closest available measure to \"first MI incidence.\" The Framingham cohort data are from 1971–1975 follow-up; contemporary rates are somewhat lower due to improved treatment, so 33% is a conservative upper bound.\n",
      "independence_note": "Framingham Heart Study is a prospective longitudinal cohort study (Framingham, MA), entirely separate from CDC NHANES cross-sectional surveys and AHA administrative data compilations. Methods are independent: Framingham uses direct clinical examination and event adjudication over decades of follow-up.\n"
    },
    {
      "url": "https://www.cdc.gov/heart-disease/data-research/facts-stats/index.html",
      "title": "Heart Disease Facts",
      "publisher": "US Centers for Disease Control and Prevention",
      "source_type": "govt_report",
      "statistic": "About 805,000 people in the United States have a heart attack each year; 605,000 are a first heart attack. Every 40 seconds someone in the US has a heart attack.\n",
      "excerpt": "\"Every year, about 805,000 people in the United States have a heart attack. Of these, 605,000 are a first heart attack and 200,000 happen to people who have already had a heart attack.\"\n",
      "source_date": "2025-01-01",
      "source_accessed": "2026-05-14",
      "archive_url": "http://web.archive.org/web/20260523073754/https://www.cdc.gov/heart-disease/data-research/facts-stats/index.html",
      "calculation_notes": "605,000 first heart attacks per year. US adult population ~260 million. Annual incidence rate: 605,000 / 260,000,000 ≈ 0.233% per year. Over 59 adult years at this rate: 1 − (1 − 0.00233)^59 ≈ 12.7% — but this double-counts survivors who may have subsequent events tracked separately, and underestimates because CDC figures include both fatal and non-fatal first MIs. The Framingham lifetime-risk method (see source 1) is the more appropriate basis for the lifetime point estimate. Used here to anchor the native display rate and corroborate the Framingham estimate.\n",
      "independence_note": "CDC Health Statistics draws on the AHA Statistical Update (2025) and NHANES surveillance. It is methodologically independent of the Framingham Heart Study prospective cohort, using administrative and survey-based data rather than direct cohort follow-up.\n"
    },
    {
      "url": "https://www.ahajournals.org/doi/10.1161/CIR.0000000000001303",
      "title": "2025 Heart Disease and Stroke Statistics",
      "publisher": "American Heart Association / Circulation",
      "source_type": "reputable_reference",
      "statistic": "Approximately 805,000 US heart attacks per year; average age of first MI is 65.5 years for men and 72 years for women; about 1 in 5 MI deaths occur before hospital arrival.\n",
      "excerpt": "\"[Paraphrase from abstract — full text paywalled] The 2025 Statistical Update reports approximately 805,000 myocardial infarctions per year in the United States, of which approximately 605,000 are first events. The average age of first MI is 65.5 years for males and 72.0 years for females. Approximately 1 in 5 MI deaths occur before hospital arrival.\"\n",
      "source_date": "2025-01-27",
      "source_accessed": "2026-05-14",
      "archive_url": "http://web.archive.org/web/20260525095140/https://www.ahajournals.org/doi/10.1161/CIR.0000000000001303",
      "calculation_notes": "Used to characterize the acute fatality fraction (~20–25%) and average age of first MI, which inform the adjustment from hard-CHD lifetime risk to surviving-first-MI lifetime risk. Not used as the primary probability estimate — the Framingham lifetime-risk method is preferred.\n",
      "independence_note": "AHA Statistics compiles administrative, survey, and cohort data from multiple independent sources (NHANES, NHLBI, Medicare claims, Framingham, ARIC, CHS). It is a secondary aggregator that draws on Framingham but synthesizes far more data and is published annually by a separate editorial team.\n"
    }
  ],
  "comparison_anchors": [
    {
      "label": "Death from heart disease (lifetime, US adult)",
      "lifetime_us_adult": 0.19
    },
    {
      "label": "Death in a car crash (lifetime, US)",
      "lifetime_us_adult": 0.0108
    },
    {
      "label": "Stroke (lifetime incidence, US adult)",
      "lifetime_us_adult": 0.25
    }
  ],
  "personal_factor_multipliers": [
    {
      "factor": "Current smoker",
      "multiplier": 2.5,
      "notes": "Framingham 34-year follow-up and multiple pooled analyses consistently show current smokers have approximately 2–3× the MI incidence of non-smokers; effect is stronger in women (RR ~2.2) than men (RR ~1.4–2.0).\n"
    },
    {
      "factor": "Hypertension (systolic BP ≥140 mmHg)",
      "multiplier": 2,
      "notes": "AHA risk-factor data: hypertension approximately doubles the risk of first MI compared to normotensive adults; risk scales with degree of elevation.\n"
    },
    {
      "factor": "Type 2 diabetes",
      "multiplier": 2.5,
      "notes": "AHA 2025 Statistics: adults with type 2 diabetes have 2–4× higher MI risk; the effect is stronger in women, partially closing the sex gap in incidence.\n"
    },
    {
      "factor": "Family history of premature MI (1st-degree relative <55M or <65F)",
      "multiplier": 2,
      "notes": "Framingham risk equations and INTERHEART study: family history of premature coronary disease approximately doubles lifetime MI risk, independent of shared lifestyle factors.\n"
    },
    {
      "factor": "Non-Hispanic Black women vs Non-Hispanic White women",
      "multiplier": 1.4,
      "notes": "AHA Statistics: Black women have higher MI incidence and younger average age of first event than White women, reflecting both biological and social determinants of cardiovascular risk.\n"
    },
    {
      "factor": "Regular aerobic exercise ≥150 min/week",
      "multiplier": 0.5,
      "notes": "Meta-analyses of physical activity and CHD: regular moderate-intensity exercise reduces MI risk by approximately 35–50% compared to sedentary adults.\n"
    }
  ],
  "short_label": "First heart attack",
  "myth_framing": "calibrated",
  "outcome_severity": "serious_harm",
  "exposure_pattern": "cumulative",
  "outcome_type": "recoverable_injury",
  "valence": "negative",
  "caveats": "This entry covers non-fatal first myocardial infarction (heart attack where the patient survives); it is distinct from heart-disease-death.mdx, which covers mortality from cardiovascular disease. The Framingham lifetime-risk figures include both MI and coronary death as \"hard events\" — the non-fatal MI subset is estimated by removing the acute fatality fraction (~20–25%). The Framingham cohort was predominantly white and recruited in 1971–1975; contemporary MI rates are somewhat lower due to statin therapy, smoking declines, and improved acute care, so the ~17% lifetime estimate is modestly conservative. Silent MI (myocardial infarction without recognized symptoms) is not captured in these figures; NHANES data suggest silent MI may account for an additional 25–40% of all MI events, meaning true MI prevalence is substantially higher than event-based incidence data suggest. Sex differences are large: lifetime risk from age 40 is roughly 42% for men vs 25% for women for all hard coronary events; the blended 17% surviving-first-MI figure reflects the full US adult population (including ages 18–40 where incidence is very low).\n",
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    "d3": 4,
    "d4": 5,
    "d5": 4,
    "d6": 5,
    "d7": 4,
    "d8": 5,
    "avg": 4.5,
    "scored_by": "claude-code-8d",
    "scored_at": "2026-05-25",
    "methodology_version": "1.2"
  },
  "reviewer": "8d-eval-2026-05-16",
  "last_reviewed": "2026-05-16",
  "reviewed": true,
  "generated_at": "2026-05-14",
  "image": {
    "alt": "An ECG heartbeat trace on a pale background, flat vector editorial illustration."
  },
  "attribution": "Likelier — https://likelier.app",
  "license": "https://creativecommons.org/licenses/by-sa/4.0/",
  "support": "https://buymeacoffee.com/kgluszczyk?via=likelier&utm_content=api-fear-single",
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}