Prevention of Disease - Secondary Prevention
screening women cancer health
The goal of secondary prevention is to identify and detect disease in its earliest stages, before noticeable
symptoms develop, when it is most likely to be treated successfully. With early detection and diagnosis, it may be possible to cure a disease, slow its progression, prevent or minimize complications, and limit disability.
Another goal of secondary prevention is to prevent the spread of communicable diseases (illnesses that can be transmitted from one person to another). In the community, early identification and treatment of people with communicable diseases, such as sexually transmitted diseases, not only provides secondary prevention for those who are infected but also primary prevention for people who come in contact with infected individuals.
Like primary prevention, secondary prevention is performed by individual health care practitioners and public health agencies and organizations. An example of secondary prevention that is conducted by many different professionals (physicians, nurses, allied health professionals) in a variety of settings (medical offices, clinics, health fairs) is blood pressure screening to identify people with hypertension (high blood pressure).
Figure 2.2 shows preventive measures for healthy adults recommended by the U.S. Preventive Services Task Force. The actions listed under the heading "Screening" are secondary prevention measures, whereas those listed under the headings "Immunization," "Chemoprevention," and "Counseling" are considered primary prevention activities.
Other diseases in which secondary prevention plays an important role are diabetes (a condition in which the body does not properly metabolize sugar), glaucoma (a disorder caused by too much fluid pressure inside the eyeball), breast cancer, and cancer of the cervix (the opening of the uterus). State and local health departments, voluntary health agencies, hospitals, medical clinics, schools, and physicians often conduct screenings for these conditions during which people with no signs or symptoms are tested to uncover these diseases in their earliest stages.
Screening and Early Detection of Breast and Cervical Cancers
The American Cancer Society estimates that in 2004 there will be 215,900 women diagnosed with breast cancer and 40,110 will die of the disease. It was estimated that 10,520 new cases of cervical cancer would be diagnosed in 2003 and 3,900 women would die of the disease. As with many other cancers, treatment for these types is most likely to be successful when it begins before the cancer has metasta-sized (spread from its original site to other parts of the body).
Mammography screening, or breast x-rays that find cancers too small to be detected by self-examination or
manual examination by a health practitioner, could prevent 16 percent of all breast cancer deaths in women older than age forty, according to the CDC in The Burden of Chronic Diseases and Their Risk Factors: National and State Perspectives. Moreover, the risk reduction associated with screening increases as women age. The Papanicolaou test, also called Pap smear or Pap test, is a screening examination for cancer of the cervix that has the potential to prevent practically all deaths from cervical cancer by finding cervical cancer at an early stage, when it is most curable, or even preventing the disease if precancerous lesions found during the test are treated. The incidence of cervical cancer has decreased dramatically in the past forty years thanks largely to screening and early treatment.
In 1990 Congress passed the Breast and Cervical Cancer Mortality Prevention Act, establishing the CDC's National Breast and Cervical Cancer Early Detection Program (NBCCEDP). The NBCCEDP provides breast and pelvic examinations, screening mammography, and Pap tests to women at greater risk of death from breast or cervical cancer—racial and ethnic minorities, those who live below the poverty level, older women, and women with less than a high school education.
After twelve years of operation, NBCCEDP has screened almost 1.8 million women, provided more than four million screening examinations, and diagnosed 14,446 breast cancers, 55,210 precancerous cervical lesions, and 1,020 cervical cancers. (See Figure 2.3 for data showing the number of women served by NBCCEDP for the years 1991–2002.) A significant component of the NBCCEDP effort is community education and outreach. Health educators must not only communicate the life-saving benefits of screening and early identification of disease but also overcome barriers to access to care, such as lack of transportation or child care.
To inform and encourage women to seek screenings, public health workers present health education programs to women's groups, distribute brochures describing how and why women should be screened, and enlist the media to help spread the message. Print advertisements appear in newspapers and magazines to promote the NBCCEDP.
The NBCCEDP also funds follow-up care for women who have positive (abnormal) screening results to enable them to receive needed services. These may include biopsy (surgical removal of a sample of cells for microscopic examination) to confirm the diagnosis and visits with surgeons and other medical specialists to receive timely treatment. The provision of follow-up care and treatment is a fundamental principle underlying screening programs.
Screening programs that do not provide facilities for diagnosis and treatment are unlikely to be effective, especially when they are serving populations unable to pay for medical care. Further, many public health professionals believe it is unethical to offer screening without plans and provisions to care for disease identified through the screening process.