Better Health: Smart Health Commentary Better Health (TM): smart health commentary

Article Comments (3)

What Is Secondary Prevention?

A November letter to the editor in American Family Physician chastises that publication for misusing the term “secondary prevention,” even using it in the title of an article that was actually about tertiary prevention.

I am guilty of the same sin. I had been influenced by simplistic explanations that distinguished only two kinds of prevention: Primary and secondary. I thought primary prevention was for those who didn’t yet have a disease, and secondary prevention was for those who already had the disease, to prevent recurrence or exacerbation. For example, vaccinations would be primary prevention and treatment of risk factors to prevent a second myocardial infarct would be secondary prevention.

No, there are three kinds of prevention: Primary, secondary and tertiary. Primary prevention aims to prevent disease from developing in the first place. Secondary prevention aims to detect and treat disease that has not yet become symptomatic. Tertiary prevention is directed at those who already have symptomatic disease, in an attempt to prevent further deterioration, recurrent symptoms and subsequent events.

Some have suggested a fourth kind, quaternary prevention, to describe “… the set of health activities that mitigate or avoid the consequences of unnecessary or excessive interventions in the health system.” Another version is “Action taken to identify patient at risk of overmedicalisation, to protect him from new medical invasion, and to suggest to him interventions, which are ethically acceptable.” But this is not a generally accepted category.

Stedman’s Medical Dictionary defines secondary prevention as “interruption of any disease process before the emergence of recognized signs or diagnostic findings of the disorder.”

The Encyclopedia Britannica defines it as “early detection of disease or its precursors before symptoms appear, with the aim of preventing or curing it.”

A CME website explains the definitions used by the USPSTF:

The U.S. Preventive Services Task Forces’ Guide to Clinical Preventive Services (2d edition, 1996) describes secondary prevention measures as those that “identify and treat asymptomatic persons who have already developed risk factors or preclinical disease but in whom the condition is not clinically apparent.” (pp xli)  These activities are focused on early case finding of asymptomatic disease that occurs commonly and has significant risk for negative outcome without treatment. Screening tests are examples of secondary prevention activities, as these are done on those without clinical presentation of disease that has a significant latency period such as hyperlipidemia, hypertension, breast and prostate cancer.  With early case finding, the natural history of disease, or how the course of an illness unfolds over time without treatment, can often be altered to maximize well-being and minimize suffering.

Tertiary prevention activities involve the care of established disease, with attempts made to restore to highest function, minimize the negative effects of disease, and prevent disease-related complications.

The Library Index says “Secondary prevention, also called ‘screening,’ refers to measures that detect disease before it is symptomatic.”

The Encyclopedia of Public Health says:

Secondary prevention generally consists of the identification and interdiction of diseases that are present in the body, but that have not progressed to the point of causing signs, symptoms, and dys-function. These preclinical conditions are most often detected by disease screening (and follow-up of the findings). Examples of screening procedures that lead to the prevention of disease emergence include the Pap smear for detecting early cervical cancer, routine mammography for early breast cancer, sigmoidoscopy for detecting colon cancer, periodic determination of blood pressure and blood cholesterol levels, and screening for high blood-lead levels in persons with high occupational or other environmental exposures.

But usage is inconsistent and confusing. In addition to American Family Physician, several other organizations and publications such as the National Library of Medicine, the British Medical Journal, and the American Heart Association use the term “secondary prevention” to include patients who already have symptomatic disease.

Is this just unimportant nit-picky quibbling by self-appointed language police? I don’t think so. Science requires precise terminology and agreement about definitions. The letter to the editor in American Family Physician gives an example of a situation where imprecision could lead to patients being harmed.  Beta blockers reduce morbidity and mortality in patients after MI, but they have been shown to increase morbidity in patients with hypertension who have not already had an MI.  If a writer recommends them for “secondary prevention” thinking he is talking about patients who have had an MI, a reader might misunderstand and give them to patients who have not yet had one.

*This blog post was originally published at Science-Based Medicine*

You may also like these posts

    None Found

Read comments »

3 Responses to “What Is Secondary Prevention?”

  1. Bertha Westbrook says:

    Thank you, information very informative , however does not answer my question. I need to know how do I teach and apply secondary intervention teaching to the topic of bedbugs?. Can you give me an example of all Primary teaching, Secondary prevention and Tertiary prevention as related to Bedbugs…Thank you

  2. Denny Brennan says:

    Harriet – Excellent post. (Knowing I’m sure to be late with this comment) I would assert that there are four domains of prevention, the fourth, Quaternary Prevention, concerns preventing patients and providers from the overmedicalization of illness. Essentially, “Do No Harm.” or What Don’t You Need to Test, Measure and/or Treat. Cheers db

  3. Denny Brennan says:

    Bertha – prevention of bedbugs would be 1 (Primary-Don’t let the bed bugs bite). Prevent intrusion and exposure. Methodology: Education, health promotion, health risk assessment (HRA) ; method of action: awareness-building, self-management, data collection. Agents: non-profit community health agencies and primary care via community health centers and hospital-based clinics; Principals: the vulnerable population. 2 (Secondary-See if they do): Testing and evaluation of patients and sites based on where infestations are certain or likely from self-referrals and community outreach based on stratification and targeting recommended from analyses of HRA data. 3. (Tertiary) Kill bugs and treat bitten with evidence-based interventions. 4. (Quaternary) Don’t go spraying for bugs where there are none. Focus on training people to raise level of personal hygiene and risk factor management.

Return to article »

Latest Interviews

IDEA Labs: Medical Students Take The Lead In Healthcare Innovation

It’s no secret that doctors are disappointed with the way that the U.S. healthcare system is evolving. Most feel helpless about improving their work conditions or solving technical problems in patient care. Fortunately one young medical student was undeterred by the mountain of disappointment carried by his senior clinician mentors…

Read more »

How To Be A Successful Patient: Young Doctors Offer Some Advice

I am proud to be a part of the American Resident Project an initiative that promotes the writing of medical students residents and new physicians as they explore ideas for transforming American health care delivery. I recently had the opportunity to interview three of the writing fellows about how to…

Read more »

See all interviews »

Latest Cartoon

See all cartoons »

Latest Book Reviews

Book Review: Is Empathy Learned By Faking It Till It’s Real?

I m often asked to do book reviews on my blog and I rarely agree to them. This is because it takes me a long time to read a book and then if I don t enjoy it I figure the author would rather me remain silent than publish my…

Read more »

The Spirit Of The Place: Samuel Shem’s New Book May Depress You

When I was in medical school I read Samuel Shem s House Of God as a right of passage. At the time I found it to be a cynical yet eerily accurate portrayal of the underbelly of academic medicine. I gained comfort from its gallows humor and it made me…

Read more »

Eat To Save Your Life: Another Half-True Diet Book

I am hesitant to review diet books because they are so often a tangled mess of fact and fiction. Teasing out their truth from falsehood is about as exhausting as delousing a long-haired elementary school student. However after being approached by the authors’ PR agency with the promise of a…

Read more »

See all book reviews »