Preventive medicine

Preventive medicine is the branch of medicine that deals not only with preventing disease from occurring, but also with halting disease progression and averting complications after disease onset. Disease prevention occurs on five levels, with measures ranging from health policies that affect the general population to specific treatments for particular patient groups: primordial prevention (actions that address environmental, socioeconomic, behavioral risk factors; e.g., smoking cessation campaigns), primary prevention (actions that inhibit the occurrence of specific diseases; e.g., immunization), secondary prevention (actions that inhibit the progress of specific diseases at an early stage to prevent or limit complications; e.g., screening), tertiary prevention (actions that inhibit the progress of specific diseases at an advanced stage to prevent or limit complications; e.g., blood pressure management in patients with hypertension), and quartenary prevention (actions that prevent over-medicalization and offer ethically acceptable interventions; e.g., pursuing nonaddictive strategies to managing chronic pain rather than prescribing opioids). One of the greatest challenges to preventive medicine is the “prevention paradox,” which states that preventive measures that benefit large populations have little impact on most people (e.g., even without measles immunization, only a relatively small proportion of the population would contract the disease). This leads to the common misconception that preventive measures provide no benefit to the individual as part of a larger population. Another challenge is poor medical adherence, i.e., the extent to which an individual follows prescribed drug regimens and medical advice, especially in patients who do not feel ill and, therefore, perceive the burden of prevention rather than its long-term benefits. Strategies to encourage adherence include a patient-centered approach, frequent follow-ups, and education regarding long-term consequences of medical conditions, behaviors, and lifestyle.

See also “Well-child visits” and “Adolescent health care.”

Public health interventions are actions and policies introduced by public health authorities to protect and improve the health of a population. Population-based practice focuses on the health concerns of entire populations and intervenes at the individual, community, and systemic levels. ^[1]

• Definition: actions that address environmental, socioeconomic, and behavioral risk factors that affect a population as a whole to prevent potential disease or injury.
• Measures ^[2][3]
  • Target: entire population
  • Health promotion beginning in childhood to encourage positive and discourage negative lifestyle habits
  • Mass education
  • Legislation
• Examples
  • Programs on food safety and nutrition guidelines
  • Campaigns discouraging tobacco and drug use (e.g., smoke-free air laws in public buildings)
  • Building bicycle and sidewalks to promote physical activity

Primordial prevention aims to prevent risk factors from developing in the first place, whereas primary prevention targets existing risk factors to prevent the onset of a disease.

• Definition: actions targeted at preventing specific diseases from occurring to decrease the incidence and, subsequently, the prevalence of those diseases
• Measures ^[3][4]
  • Target: entire population and select groups (healthy individuals)
  • Decrease incidence and, in turn, prevalence of a specific disease
  • Primarily done through
    • Health promotion (health interventions, lifestyle modifications)
    • Environmental modifications (e.g., work safety)
    • Specific protection interventions (immunizations, chemoprophylaxis, safety of drugs and food)
• Examples
  • Immunization
  • Lifestyle modification (e.g., smoking cessation to reduce lung cancer risk, exercise to reduce the risk of heart disease, dental care to reduce the risk of tooth loss)
  • Fortification of salt with iodine to prevent iodine deficiency
  • Fluoridation of toothpaste, water, and salt to reduce the risk of dental conditions
  • Fortification of food with folic acid to reduce the prevalence of neural tube defects
  • Health legislation (e.g., seat belt laws, food safety standards, traffic laws)
  • Ocular prophylaxis for all newborns to prevent neonatal gonococcal conjunctivitis

Primary prevention helps to Prevent disease.

• Definition: actions targeted at early detection of disease in asymptomatic patients (or while the symptoms of the condition are still mild) to promote early intervention
• Measures ^[3]
  • Target: patient groups
  • Prevent further progression and complications from the disease
  • Consists of a two-step process: screening test to identify disease and follow-up for disease management

The screening recommendations covered below are primarily based on the United States Preventive Services Task Force (USPSTF) unless stated otherwise.

Screening complements diagnostics, but it is not a substitute.

Secondary prevention helps Screen.

These screening recommendations are a summarized version of the most important screening interventions. For more detailed information, please refer to the respective disease articles.

• For screening tests in pregnant women, see “Prenatal care.”
• For screening tests in transgender individuals, see: “Preventive health care of transgender individuals.”

These screening recommendations are a summarized version of the most important screening interventions. For more detailed information, please refer to the respective disease articles. For screening tests in transgender individuals, see: “Preventive health care of transgender individuals.”

These screening recommendations are a summarized version of the most important screening interventions. For more detailed information, please refer to the respective disease articles.

These screening recommendations are a summarized version of the most important screening interventions. For more detailed information, please refer to the respective disease articles.

These screening recommendations are a summarized version of the most important screening interventions. For more detailed information, please refer to the respective disease articles.

These screening recommendations are a summarized version of the most important screening interventions. For more detailed information, please refer to the respective disease articles.

These screening recommendations are a summarized version of the most important screening interventions. For more detailed information, please refer to the respective disease articles.

• Definition: actions taken to optimize care of patients with an existing disease to improve well-being and prevent complications
• Measures ^[3]
  • Target: select patient groups
  • Decrease the risk of relapse
  • Decrease morbidity and mortality after the onset of symptoms (e.g., implement strategies to improve treatment adherence)
• Examples
  • Adjuvant therapy (e.g., tamoxifen in breast cancer) to reduce risk of cancer recurrence
  • Blood pressure management (e.g., antihypertensives) to decrease risk of a cardiovascular event
  • Diabetes management (e.g., antidiabetic medication, HbA_1c monitoring) to decrease risk of chronic kidney disease and/or cardiovascular events
  • Measures to prevent restenosis following myocardial infarction (e.g., low-dose aspirin)

Tertiary prevention helps Treat.

• Definition: actions taken to avoid unnecessary medical interventions by identifying actions that might cause harm rather than benefit patients
• Measures ^[3][16][17]
  • Target: patient groups
  • Prevent overmedicalization (e.g., overdiagnosis, overtreatment)
  • Avoid unnecessary diagnostic studies or treatments without proven efficacy (e.g., only offer ethically acceptable interventions, use treatments previously assessed by randomized controlled trial with low risk of bias)
  • Avoid disease mongering, i.e., widening the definition of certain medical illnesses, to expand markets for those who deliver and/or sell medical treatments.
• Examples ^[18]
  • Avoid hormone replacement therapy after menopause in order to reduce risk of cardiovascular events (e.g., stroke, thromboembolism).
  • Avoid prescribing antibiotics if uncertain that the disease has a bacterial cause (may lead to antibiotic resistance).
  • Discontinue oral antidiabetic medication (e.g., sulfonylureas) due to adverse effects (e.g., multiple hypoglycemic events).
  • Avoid overdiagnosis (e.g., recurrent PSA testing in men without high risk for prostate cancer, MRI or CT scan for lower back pain of < 6 weeks duration or without red flags).

QUaternary prevention helps sQUeeze out unnecessary treatments.

• Definition ^[19][20]
  • A preventive measure that benefits a population as a whole will offer little benefit to each individual member of that population (population approach to prevention; primordial and primary prevention)
  • A preventive measure that benefits a group of individuals susceptible to a particular disease will offer little benefit to the population as a whole (high-risk approach to prevention; secondary and tertiary prevention).
  • The high-risk approach and the population approach to prevention are complementary, but preventive medicine should prioritize preventing the underlying causes of disease (primordial and primary prevention) over reducing the impact of disease after it occurs (secondary and tertiary prevention).
  • The prevention paradox may lead to the misconception that a measure that provides no immediate benefit to the individual, provides no benefit to the entire population and that a small risk involved in a measure (e.g., vaccination) outweighs the benefits of that measure.
    • Misconceptions derived from the prevention paradox may negatively affect epidemiological policy as well as adherence in the population.
    • Primordial and primary prevention require consistent, long-term education programs for health care professionals as well as the general population to be effective.
• Examples
  • While heavy drinking carries a greater risk than moderate drinking, moderate drinking has a greater negative impact on the general population because the number of moderate drinkers is greater than that of heavy drinkers.
  • Seatbelt laws have prevented many severe injuries, yet the overall risk of dying in an accident due to not wearing a seatbelt is still low.

• Definitions
  • Disease cluster: an unusual aggregation, real or perceived, of cases of a disease that are grouped together in time and space
  • Disease outbreak: the sudden occurrence of more cases of a disease than expected in a given area, population, and/or season
• Indentifying outbreaks
  • Outbreaks are identified by health authorities through reports that may come from hospitals, laboratories, health care providers, and even the general population.
  • After receiving an initial report, health authorities decide on whether to investigate further.
• Investigating outbreaks
  • Field investigation involves identifying a potential disease outbreak, forming a hypothesis about its cause, gathering data to test the hypothesis, and finally, developing and implementing control and prevention measures.
  • Steps of the field investigation usually include:
    • Preparing for the investigation
      • Gathering information about the condition, area, and/or population of interest
      • Organizing a team and necessary supplies
    • Confirming the outbreak
    • Establishing a case definition
    • Finding cases and documenting details of each case
    • Developing a hypothesis about the cause of the outbreak
    • Analyzing the gathered data and evaluating the hypothesis
    • Comparing and reconciling with laboratory and/or environmental studies
    • Developing and implementing control and prevention measures
    • Initiating or maintaining surveillance.
    • Communicating the findings to the public

• The Whole School, Whole Community, Whole Child (WSCC) model is a student-centered framework developed by the CDC for addressing health in schools.
• WSCC consists of ten components:
  • Physical education and physical activity
    • Physical activity recommendations are outlined in the Comprehensive School Physical Activity Program, which consists of five components: physical education, physical activity during school, physical activity before and after school, staff involvement, and family and community engagement.
    • Physical education is an academic subject for all K-12 students, which helps to develop motor skills, knowledge, and behaviors for a healthy lifestyle.
  • Nutrition environment and services
    • Food provided to students must meet the Nutrition Standards for School Meals issued by the USDA.
    • Free drinking water must be available to all students throughout the day.
    • The National School Lunch and Breakfast Programs provide nutritious, low-cost or free meals to children each school day.
  • Health education: Integration of health education into the curriculum involves addressing topics such as nutrition, mental health, sexual health, violence prevention, and the use of alcohol, tobacco, and other substances in a variety of subjects and educational settings.
  • Social and emotional climate: A positive emotional climate is essential for proper child development and should be maintained in all aspects of school functioning.
  • Physical environment: School buildings and surrounding environment should be safe from any health threat (e.g., traffic, crime, construction, improper ventilation).
  • Health services: Services from qualified health professionals (e.g., nurses, physicians, physician assistants) should be available to all students.
  • Counseling, psychological, and social services: prevention and intervention to support the mental, behavioral, and social health of students (i.e., with certified school counselors, school psychologists, and school social workers)
  • Employee wellness: School employees should have access to programs, policies, and benefits that promote their health and well-being.
  • Community involvement: partnerships with local groups, organizations, and businesses to encourage students' civic engagement and to share school resources (e.g., school-based health centers and sports facilities) with the community
  • Family engagement: continuous involvement of students' families in educational activities and development