Premature heart attack: risks and prevention

What is a premature heart attack, and what do the available data actually show?

A “premature heart attack” is defined according to the age threshold used by each study or guideline; it does not automatically mean every heart attack occurring before age 60. Brazilian guidance defines a family history of premature atherosclerotic disease as an event occurring before age 55 in men or 65 in women, while reviews and European guidance use other thresholds according to the clinical and family-history context^1,2,3. The figures previously attributed to a Rede D’Or survey—4,921 patients evaluated between January 2025 and March 2026—were not retained because no publication, institutional report or public preliminary dataset with verifiable methods was located. A publicly accessible alternative is SIH/SUS, an administrative database built from hospital admission authorisations funded by Brazil’s public health system⁴. It can be queried by diagnosis, location, period and age group, but it does not cover all private care, and its admissions should not automatically be interpreted as unique patients or population incidence⁴. Comparisons between cities or states require uniform case definitions, population denominators, information on healthcare coverage and adjustment for demographic differences. Administrative data cannot calculate an individual resident’s risk, and a specific analysis of Santos or the Baixada Santista area would have to be conducted separately⁴.

Why can a heart attack occur at a young age?

A heart attack may occur early when genetic, medical and behavioural factors accelerate processes that usually accumulate over decades. Atherosclerosis is cumulative: prolonged exposure to LDL and other apolipoprotein B-containing particles promotes cholesterol deposition within artery walls, and persistently elevated levels from an early age increase lifetime cardiovascular risk^1,5,3. In most type 1 heart attacks, a blood clot forms over an atherosclerotic plaque that has ruptured or eroded. A young person may have a lower overall plaque burden but still carry a vulnerable plaque capable of triggering an acute event⁶. Not every heart attack in a young adult results from traditional obstructive atherosclerosis. Other mechanisms include spontaneous coronary artery dissection, coronary spasm, embolism or thrombosis, stimulant drug use, inflammatory or autoimmune conditions and hypercoagulable states. When myocardial infarction criteria are met without significant coronary obstruction, MINOCA is used as a working diagnosis and further investigation is required to establish the mechanism and exclude alternative diagnoses⁶. Establishing the cause matters because treatment and prevention of another event may differ.

Which factors can bring cardiovascular disease forward?

Smoking, diabetes, high cholesterol, hypertension, excess weight and family history are consistently associated with premature heart attacks. The strength of each association varies according to the population, age definition and study design, and population-level findings are not an individual probability forecast². A case-control study of 4,528 young adults evaluated diabetes, hypertension, smoking, family history of premature heart attack, hypercholesterolaemia, depression and low household income. In that study, the combined factors had an estimated population-attributable fraction of approximately 84% among women and 85% among men. This measure depends on the associations and prevalence of the factors in the study population and does not represent the proportion of risk explained in an individual⁷. Family history raises risk but does not make a heart attack inevitable. Record which parents, siblings or children were affected, what happened and their age at the event^1,2,5,3. Persistently high LDL cholesterol at or above 190 mg/dL represents a severe elevation, may suggest familial hypercholesterolaemia and warrants medical assessment, investigation of secondary causes and review of the wider family history¹. Living in São Paulo does not by itself determine cardiovascular risk. Psychosocial stress is recognised as a risk modifier, but this does not prove that stress caused a particular person’s heart attack or differences between locations³. The meta-analysis reported an OR of 1.01 per 10 µg/m³ increase in PM10 (95% CI 1.00–1.02), corresponding to an estimated increase of approximately 1% in the odds. The effect was small and close to the null value, and the observational evidence does not establish causality. Neither this estimate nor administrative data can attribute age differences between locations to pollution or pace of life^4,8.

When and how should cardiovascular risk be assessed?

Cardiovascular assessment in a young adult should combine medical history, physical findings and selected tests rather than relying on age alone. The assessment may include symptoms, medicines and substance use, family history, blood pressure, weight, waist circumference, blood glucose or HbA1c and a standard lipid profile^1,5,3. Brazilian guidance recommends cardiovascular risk stratification and recognition of risk enhancers that may not be adequately represented by short-term scores, especially in young adults¹. The publicly available US source used in this article is the 2019 ACC/AHA guideline: it recommends assessing traditional factors between ages 20 and 39 and calculating 10-year risk in selected adults aged 40–75; lifetime or 30-year estimates may be considered in specified age groups. No US guideline attributed to 2026 was used because it was not publicly available when the sources were checked⁵. Ten-year scores often produce low figures in young adults, but this does not rule out high lifetime risk in someone with elevated LDL, smoking, diabetes, hypertension or a strong family history^1,5. Lipoprotein(a), or Lp(a), is largely genetically determined and is not included in a conventional lipid panel. European guidance recommends considering its measurement at least once in adulthood, while US guidance recognises its value in settings such as a family history of premature disease. Levels at or above approximately 50 mg/dL or 125 nmol/L are considered risk-enhancing, although the units cannot be universally interconverted with a single conversion factor^5,3. A high Lp(a) result does not mean that a heart attack will definitely occur, but it may support more intensive management of modifiable factors. Apolipoprotein B, genetic testing and imaging should be selected according to clinical context rather than ordered indiscriminately. Coronary artery calcium scoring is not a routine test for every young adult. It may help when a prevention decision remains uncertain, particularly from age 40 and in situations such as a family history of premature atherosclerotic disease^1,5.

How can young adults reduce their heart-attack risk?

Effective prevention begins before symptoms develop and combines sustainable habits with timely diagnosis and treatment. The American Heart Association’s eight components of cardiovascular health are diet, physical activity, freedom from nicotine exposure, healthy sleep, body weight, blood lipids, blood glucose and blood pressure⁹. A preventive eating pattern prioritises fresh or minimally processed foods, fruit, vegetables, whole grains, legumes, nuts and appropriate protein sources. Ultra-processed foods, excess salt, added sugars and saturated fat should be limited⁹. Adults should aim for at least 150 minutes of moderate activity or 75 minutes of vigorous activity each week while reducing sedentary time. Exercise should be adapted to fitness, symptoms and existing health conditions⁹. Avoiding tobacco means quitting conventional cigarettes, avoiding e-cigarettes and other nicotine products, and reducing second-hand exposure^2,9. Most adults should aim for approximately seven to nine hours of sleep each night⁹. September’s Heart Month and World Heart Day on 29 September offer a useful reminder, but these preventive steps matter throughout the year. Hypertension, diabetes and high cholesterol may cause no symptoms before damage occurs, making periodic measurements important even for people who feel healthy^1,5,9,3. Medicines to lower LDL cholesterol, blood pressure or glucose may be necessary according to overall risk, but they should not be started without medical advice or prescribed solely because of age or one isolated number^1,5,3.

When do symptoms require immediate medical attention?

Persistent chest pain or pressure—especially with shortness of breath, cold sweats, pallor, nausea or a faint feeling—should be treated as an emergency. Discomfort may spread to an arm, the back, jaw or upper stomach area¹⁰. In Brazil, including for international visitors, expatriates and crew members in Santos or around the Port of Santos, call SAMU on 192 or seek an emergency department immediately¹⁰. Young adults can also experience a heart attack, so age should never be used to dismiss compatible symptoms.

What are the common questions, and which references were used?

Individual risk reflects the combined effects of modifiable factors, genetics, associated medical conditions and duration of exposure—not age or place of residence alone. “Can an active person still have a heart attack?” Yes. Exercise lowers risk but cannot eliminate familial hypercholesterolaemia, diabetes, hypertension, previous smoking exposure or non-atherosclerotic mechanisms. “If a parent had a heart attack, will I have one too?” No. Family history is an important risk enhancer, but prevention, early diagnosis and appropriate treatment can substantially modify risk^1,2,5,3. “Does every young adult need an Lp(a) test or a coronary calcium scan?” Lp(a) measurement may be considered at least once in adulthood, whereas coronary calcium scoring is reserved for selected situations. Both decisions require individual clinical interpretation^1,5,3. References:⁴ Brazilian Ministry of Health, Department of Health Informatics—DATASUS. Brazilian Hospital Information System (SIH/SUS): SUS Hospital Morbidity and technical notes. Institutional administrative database built from hospital admission authorisations; it is neither a published study nor a preliminary Rede D’Or dataset. Brasília: Ministry of Health; 2024. Methods and access: https://datasus.saude.gov.br/acesso-a-informacao/morbidade-hospitalar-do-sus-sih-sus/. Accessed 8 March 2025.¹ Faludi AA, Izar MCO, Saraiva JFK, et al. Atualização da Diretriz Brasileira de Dislipidemias e Prevenção da Aterosclerose — 2017. Arquivos Brasileiros de Cardiologia. 2017;109(2 Suppl 1):1–76. DOI: https://doi.org/10.5935/abc.20170121. Accessed 8 March 2025.² Egred M, Viswanathan G, Davis GK. Myocardial infarction in young adults. Postgraduate Medical Journal. 2005;81(962):741–745. DOI: https://doi.org/10.1136/pgmj.2004.027532. Accessed 8 March 2025.⁶ Tamis-Holland JE, Jneid H, Reynolds HR, et al. Contemporary Diagnosis and Management of Patients With Myocardial Infarction in the Absence of Obstructive Coronary Artery Disease: A Scientific Statement From the American Heart Association. Circulation. 2019;139(18):e891–e908. DOI: https://doi.org/10.1161/CIR.0000000000000670. Accessed 8 March 2025.⁷ Lu Y, Li SX, Liu Y, et al. Sex-Specific Risk Factors Associated With First Acute Myocardial Infarction in Young Adults. JAMA Network Open. 2022;5(5):e229953. DOI: https://doi.org/10.1001/jamanetworkopen.2022.9953. Accessed 8 March 2025.⁵ Arnett DK, Blumenthal RS, Albert MA, et al. 2019 ACC/AHA Guideline on the Primary Prevention of Cardiovascular Disease. Circulation. 2019;140(11):e596–e646. DOI: https://doi.org/10.1161/CIR.0000000000000678. Accessed 8 March 2025. This is the US guideline used; no guideline attributed to 2026 was considered.⁹ Lloyd-Jones DM, Allen NB, Anderson CAM, et al. Life’s Essential 8: Updating and Enhancing the American Heart Association’s Construct of Cardiovascular Health. Circulation. 2022;146(5):e18–e43. DOI: https://doi.org/10.1161/CIR.0000000000001078. Accessed 8 March 2025.³ Visseren FLJ, Mach F, Smulders YM, et al. 2021 ESC Guidelines on cardiovascular disease prevention in clinical practice. European Heart Journal. 2021;42(34):3227–3337. DOI: https://doi.org/10.1093/eurheartj/ehab484. Accessed 8 March 2025.¹⁰ Brazilian Ministry of Health. Acute myocardial infarction; Mobile Emergency Care Service—SAMU 192. Brasília: Ministry of Health; 2023. URLs: https://www.gov.br/saude/pt-br/assuntos/saude-de-a-a-z/i/infarto and https://www.gov.br/saude/pt-br/composicao/saes/samu-192. Accessed 8 March 2025.⁸ Luo C, Zhu X, Yao C, et al. Short-term exposure to particulate air pollution and risk of myocardial infarction: a systematic review and meta-analysis. Environmental Science and Pollution Research. 2015;22(19):14651–14662. URL: https://pubmed.ncbi.nlm.nih.gov/?term=%22Short-term+exposure+to+particulate+air+pollution+and+risk+of+myocardial+infarction%22. Accessed 8 March 2025. A medical consultation places test results in the context of your symptoms, history, lifestyle and personal goals. This content is for information and education only and does not replace an individual medical consultation.