Rational care or rationing care? Updates and controversies in women's prevention.
|Abstract:||Prevention has potential benefits, but the majority of people undergoing disease screening will receive no benefit and may actually be exposed to health risks. Public opinion is generally very favorable toward prevention. However, many recent guidelines recommend fewer preventive services in women than previously suggested. New recommendations are to wait until 50 for mammography screening, to screen only every other year, and to not teach self breast examinations. Papanicolaou tests for cervical cancer screening are recommended to be done less often (every 2-3 years) and to be started later than previously suggested (not before age 21). Screening for ovarian cancer is not recommended. Guidelines suggest avoiding hormone therapy for primary prevention of coronary heart disease, not giving aspirin to prevent myocardial infarctions in women, and not screening women without risk factors for hyperlipidemia. These recommendations have caused confusion and, because of being revealed during a national health reform debate, have even been perceived as "rationing care." Others see them as "rational care," because they encourage utilization of beneficial services while discouraging use of those that may lead to more harms than benefits. Development of prevention guidelines requires value judgments, so despite the use of evidence, these recommendations have not all achieved widespread support. Understanding the data behind the guidelines, health care providers can decide how to approach prevention in practice, taking into consideration individual patient risk factors and preferences.|
Preventive health services (Standards)
Cervical cancer (Diagnosis)
Cervical cancer (Care and treatment)
Cervical cancer (Prevention)
Cervical cancer (Patient outcomes)
Breast cancer (Prevention)
Breast cancer (Diagnosis)
Breast cancer (Care and treatment)
Breast cancer (Patient outcomes)
Mortality (United States)
Ovarian cancer (Patient outcomes)
Ovarian cancer (Diagnosis)
Ovarian cancer (Care and treatment)
Cardiovascular diseases (Prevention)
Cardiovascular diseases (Diagnosis)
Cardiovascular diseases (Patient outcomes)
Cardiovascular diseases (Risk factors)
|Publication:||Name: West Virginia Medical Journal Publisher: West Virginia State Medical Association Audience: Academic Format: Magazine/Journal Subject: Health Copyright: COPYRIGHT 2011 West Virginia State Medical Association ISSN: 0043-3284|
|Issue:||Date: Jan-Feb, 2011 Source Volume: 107 Source Issue: 1|
|Topic:||Event Code: 350 Product standards, safety, & recalls|
|Product:||Product Code: 8000140 Health Problems Prevention; 9105230 Health Problems Prevention Programs NAICS Code: 621999 All Other Miscellaneous Ambulatory Health Care Services; 92312 Administration of Public Health Programs|
|Geographic:||Geographic Scope: United States Geographic Code: 1USA United States|
Prevention has potential benefits, but the majority of people undergoing disease screening will not be benefitted and may actually be exposed to health risks. Public opinion is generally very favorable toward prevention. Eighty-seven percent of nationally surveyed adults believed cancer screening is almost always good and two thirds indicated that they would be tested even if nothing could be done for abnormal findings. (1) Many women would continue Papanicolaou (Pap) testing to screen for cervical cancer even if their physician recommended against it. (2) Women who have had a hysterectomy often continue to get Pap tests despite recommendations against doing so. (3) Despite this apparent enthusiasm, many beneficial preventive services, such as breast and colorectal cancer screening, are under utilized. (4)
Experts evaluate several factors to balance potential benefits and harms before recommending a preventive service. USP-STF (United States Preventive Services Task Force) recommendations are considered by many to be the "gold standard" for prevention guidelines. The task force grades the strength of evidence for each service as A or B (recommended), C (recommended against using routinely), D (recommended against), or I (insufficient evidence to recommend for or against). Several guidelines have recently been updated to recommend doing less prevention in women than previously suggested. These recommendations have caused widespread confusion and, because of being revealed during a national health reform debate, have even been perceived as "rationing care." This article reviews recent data and compares different organizations' prevention guidelines for average risk women.
Breast cancer is the most common non-skin malignancy in US women and the second leading cause of cancer deaths, after lung cancer. (1) in 8 women will get breast cancer in their lifetimes. Fortunately there is a 90% 5-year survival if it is localized at diagnosis, so early detection is important. However, mammography does not prevent a woman from getting cancer, and detecting it early does not necessarily mean a life is saved. Mammography screening has a sensitivity of 77-95% and a specificity of 94-97%. PPV (positive predictive value) varies by age, being lower in women in their 40's compared to women in their 50's and 60's because of the lower prevalence. Evidence indicates reduced mortality with mammography screening. However, there is also potential for harms such as false positives, anxiety, unnecessary procedures, and overdiagnosis. DCIS (ductal carcinoma in situ), a non-invasive cancer, may be an example of overdiagnosis. It has low potential for progression to invasive cancer, with less than half of cases progressing. DCIS cases get treated with surgery and radiation because it is not possible to predict which will progress. (5)
The second publication was a CISNET (Cancer Intervention and Surveillance Modeling Network) modeling study of screening strategies. Computer modeling is useful because the long follow-up and expense make conduction of randomized controlled screening trials challenging. Models can predict outcomes under different strategies, adjusting the intervals between screening and the starting/ stopping ages. This study compared 20 screening strategies, including 10 different screened age groups, each with annual and biennial testing. (7)
Most of the strategies that were found to be efficient (with efficient strategies having more health gains from fewer resources) utilized a biennial screening interval and initiated screening at age 50. A biennial screening interval was found to be beneficial in terms of both mortality and life-years gained. Harms were greater with annual compared to biennial screening, with more false positives, unnecessary biopsies, and overdiagnosis. Biennial screening was calculated to keep 81% of the mortality benefits of annual screening with about half the harms. (7)
Findings for optimal screening ages were not as clear as findings for interval. Screening initiation at age 50 was efficient for the outcome "mortality." However, initiation at 40 was efficient for the outcome of "life-years gained" due to the additional years of life expectancy. In absolute terms, compared to screening a baseline group of women aged 50-69, it was estimated that adding 10 years of screening to those 70-79 would save 2 lives per 1000 women. If those 10 additional years of screening were instead added to those 40-49, 1 life per 1000 women would be saved (half as many). However, looking at a different outcome, life-years gained would be greater from starting earlier rather than stopping later (33 vs. 24 life-years per 1000 women screened). More harmful false positives and more biopsies would occur with screening initiation at 40 compared to 50. However, overdiagnosis would be more of a problem if 10 years of screening were added by extending screening to age 79 rather than by starting screening at 40. (7)
With the publication of these studies in November 2009, USPSTF updated their screening guidelines to recommend mammograms every 2 years starting at age 50 (B recommendation). The new recommendations call for individualized decision-making and consideration of benefits/ harms before the age of 50 (C recommendation). (5) The task force had previously recommended annual mammography starting at 40. These guideline changes created a significant amount of controversy, and many politicians, health care organizations, and US women disputed them. One criticism was that USPSTF did not emphasize the data on life-years gained as much as the data on mortality. Also, the CISNET study was limited, as are all computer modeling studies, by the fact that modeling requires assumptions. Many opponents disagreed with the value judgments of the task force, with some believing that additional false positives, anxiety, and cost are worthwhile if even a small number of lives are saved.
Other organizations' screening recommendations vary, as shown in Table 2. (8-10) ACP (American College of Physicians) guidelines, which preceded USPSTF, resemble the new task force recommendations, and were based on similar reasoning. (8) Guidelines in many other countries such as Canada, Britain, and Italy, as well as the World Health Organization, target the age group of 50-69 for screening. (11)
Screenings with modalities other than mammography have been considered. Breast MRI is more sensitive than mammography but less specific. No mortality data is available. Breast cancer screening with MRI is only recommended by ACS (American Cancer Society), and only for high risk (>15% lifetime risk, which can be determined by online calculators that consider risk factors). (9) USPSTF gives screening breast MRI an I statement for insufficient evidence. (5,9)
Recommendations for screening with breast examination are shown in Table 3. Clinical breast examination (CBE) has a sensitivity of 40-69%, specificity of 88-99%, and a PPV of 4-50%. There is no mortality data available. While USPSTF says that the evidence is insufficient to address CBE, ACOG and ACS still recommend it. (5,9,10) Breast self examination (BSE) has a sensitivity around 26%. Two large trials including over 300,000 women showed no difference in breast cancer mortality with BSE, and only one showed increased detection. More biopsies were done in the intervention arm so it may do more harm than good. (12) ACS and ACOG (American College of Obstetrics and Gynecology) recommend BSE with some reservations. (9,10) However, USPSTF now recommends against teaching BSE (D recommendation), a change from their previous I statement. (5) This was announced with their new mammogram recommendations, adding to the screening controversy.
Cervical cancer is decreasing in incidence, but is still the 10th leading cause of cancer death in women. Pap tests are the mainstay of screening. HPV is known to be a necessary precursor and HPV testing can be done in conjunction with a Pap test. Most cervical cancer deaths occur in women who had not been screened in the last 5 years. Survival depends heavily on stage at diagnosis. Ninety-two percent will survive 5 years when cancer is localized but only 13% will survive distant disease. The sensitivity of a single Pap test is 60-80% for high-grade lesions. Observational evidence strongly suggests that Pap test screening programs reduce cervical cancer incidence and mortality. (5) Institution of these programs is considered to be one of the biggest cancer screening success stories. However, potential harms from screening exist. Surgical intervention such as LEEP (loop electrosurgical excision procedure) for cervical lesions has been associated with approximately twice the risk of preterm birth (RR 1.99, 95% CI 1.81-2.2), and some of the increase in US preterm births has been attributed to these interventions. (13,14) Cone biopsy procedures have also been associated with increased rates of low birth weight, PPROM (preterm premature rupture of membranes), and perinatal mortality. (15)
USPSTF strongly recommends Pap tests (A recommendation) beginning within 3 years of sexual activity or 21 (whichever comes first). (5) ACS generally agrees with the task force, but ACOG has recently suggested that Pap test screening before age 21 should be avoided, regardless of the age of starting sexual activity. (9,16) ACOG's recommendations are based on the potential harms and a less than 1 in a million chance of cervical cancer in women under 21. (17) The rationale is that most dysplastic lesions are low-grade and transient, and treating lesions that will regress spontaneously could lead to inappropriate interventions that may do more harm than good.
USPSTF and ACOG both
recommend stopping screening around age 65 if the woman has had adequate recent normal Pap tests. Both organizations also recommend stopping after hysterectomy done for benign reasons. Because there is a long progression time of preinvasive lesions to invasive cancer (around 10 years), USPSTF guidelines recommend a Pap test screening interval of every 3 years. ACOG and ACS now agree that annual screening is too frequent unless there is a history of cervical cancer or dysplasia, with ACOG recommending Pap tests every two years before the age of 30. After the age of 30, ACOG guidelines state that screening can be done every 3 years if there have been 3 negatives. If HPV testing is done and is negative in women >30, they also recommend not screening more often than every 3 years. (5,9,16)
These new ACOG cervical cancer screening guidelines were released in November 2009, just days after the release of the USPSTF mammogram guidelines. The concept of annual lifetime Pap testing had been widely embraced in the US despite the fact that USPSTF had been recommending longer cervical cancer screening intervals since 1996. The news of these ACOG recommendations to start Pap tests later and to do them less often seemed to some like a radical shift that would take care away from women.
Ovarian cancer does not have a high prevalence, striking only 50 of 100,000 women. However, it is important in terms of mortality. It is the 5th leading cause of cancer death in US women. Treatment is more effective for presymptomatic disease, with an estimated 40% reduced mortality with early diagnosis. One reason for the high fatality rate of ovarian cancer is that >70% of women are diagnosed with advanced stage disease.
The CA-125 test is often elevated in ovarian cancer, a finding that led to considering use of the test for ovarian cancer screening. Despite the fact that ovarian cancer would be a good disease for a screening program, the CA-125 doesn't have the test characteristics necessary for a screening test. It has a very low PPV because of the low prevalence of the disease, (5) and abnormal CA-125 tests often require ultrasounds or even surgery to make a definitive diagnosis. There is currently no data showing a decreased mortality with testing, but the Prostate, Lung, Colorectal and Ovarian (PLCO) trial is an ongoing large randomized controlled trial looking at mortality. It involves screening women with both a CA-125 and a transvaginal ultrasound vs. usual care. Recently, data has been evaluated from women in the intervention arm after the first 4 rounds of screening. Only 6 invasive cancers were detected per 10,000 screens. The surgery to detected cancer ratio showed that 20 oophorectomies were done to find 1 case of invasive cancer. 72% of the detected cancers were stage III and above, so it did not find early cancers as had been hoped. The PPV was poor at around 1%.18 Women sometimes ask their providers to order CA-125 tests, but while final results are pending, there is no current evidence for screening with either CA-125 or transvaginal ultrasound. Routine ovarian cancer screening has never been recommended by any organization, and USPSTF has recommended against it since 1996 (D recommendation). (5)
Without a good screening test, diagnosing ovarian cancer early requires having a low threshold for working up symptoms such as pelvic pain, increased abdominal size, urinary urgency, and bloating. These symptoms are nonspecific and often seen in primary care patients without cancer. In cancer patients compared to primary care patients, symptoms were recently found to be significantly more frequent (20-30 times per month vs. 2-3 times per month). Symptoms were also of shorter duration in cancer patients (3-6 months) vs. primary care (12-24 months). (19) An ovarian cancer symptom index is being tested in combination with CA-125 for screening. (20) Until better ovarian cancer screening methods are found, if a woman presents with these common symptoms, particularly if they are occurring almost daily (at least 12 days/ month) or if they are new (starting in the last year), it is important to evaluate them for ovarian cancer.
Heart disease is the leading cause of death in women, and preventing it could have a large public health impact. The mainstay of prevention involves reducing modifiable risk factors such as hypertension, hyperlipidemia, and smoking. Women's later development of CHD (coronary heart disease) compared to men seemed to be associated with loss of the protective effect of estrogen, which led to the use of hormone therapy at menopause for CHD prevention. That fell out of favor after the Women's Health Initiative trial showed no benefit and possible harm. (21) Aspirin and medications to reduce lipid levels are routinely used as CHD chemoprophylaxis in men, but recent studies have suggested that responses to these agents may vary by gender.
The Women's Health Study was the largest trial of aspirin for primary prevention in women, following almost 40,000 health professionals for 10 years. For the primary end point of major cardiovascular events, there was a non-significant finding (RR 0.91, 95% CI .80-1.03). No effect was seen on risk of MI (myocardial infarction) or death from cardiovascular causes. Aspirin lowered women's stroke risk (RR 0.83, 95% CI .69-.99) with a number needed to treat of 444. The benefit of aspirin for stroke was offset by an increased risk of GI bleeding with a number needed to harm of 553 for GI bleeding requiring transfusion. Only in a subgroup analysis of women older than 65 was a reduced risk seen for MI and major cardiovascular events. This study's findings were opposite to other studies' findings of reduced risk for MI but not stroke in men using aspirin. Limitations included the low dose of aspirin of 100 mg every other day and the low risk characteristics of the study population, including a young mean age of 55. (22)
USPSTF updated their guidelines for aspirin for primary prevention after this study was published, noting that aspirin does not decrease MIs in women. For stroke prevention, they recommend using aspirin in women when potential benefits outweigh potential for GI bleeding (A recommendation). A table available on the USPSTF website can help with this tricky risk-benefit analysis. If used, aspirin is not recommended until age 55, which is 10 years older than the recommended starting age for MI prevention in men. (5)
In a systematic review of lipid lowering for primary prevention in women, only one of four trials reported lower mortality in treated women. In the pooled analysis, there was no significant reduction in mortality, CHD mortality, nonfatal MI, CHD events, or revascularization. These results were limited by short follow-up, a young mean age of 60, and a low number of events. (23)
Despite widespread agreement that further research with longer follow-up is needed, in 2008 USPSTF scaled back their recommendations for lipid screening in women. The task force had previously recommended routinely screening women at age 45 and screening anyone high risk at 20. The new recommendation is to screen women only if they have increased risk at any age (A recommendation for age 45 or greater, B recommendation for ages 20-45). They give no recommendation for or against screening women who are not at increased risk (C recommendation). Their rationale is that the known benefits of lipid treatment only outweigh the harms (which are admittedly small) when the CHD risk is substantial. (5)
Many recent guidelines recommend doing less prevention in women than previously suggested. Some of the new recommendations are to wait until 50 for mammography screening, to screen only every other year, and to not teach SBEs, although not all organizations are in agreement. Pap tests for cervical cancer screening are recommended to be done less often (every 2-3 years) and to be started later than previously suggested (not before age 21). Screening for ovarian cancer is not recommended. Guidelines suggest avoiding hormone therapy for primary prevention of coronary heart disease, not giving aspirin to prevent MIs in women, and not screening women without risk factors for hyperlipidemia.
Some perceive these guidelines as "rationing care." Others see them as "rational care," because they encourage utilization of beneficial services while discouraging use of those that may lead to more harms than benefits. Development of prevention guidelines requires value judgments, so despite the use of evidence, these recommendations have not all achieved widespread support. Understanding the data behind the guidelines, health care providers can decide how to approach prevention in practice, taking into consideration individual patient risk factors and preferences.
(1.) Schwartz LM, Woloshin S, Fowler FJ, Jr., Welch HG. Enthusiasm for cancer screening in the United States. JAMA. Jan 7 2004;291(1):71-78.
(2.) Sirovich BE, Woloshin S, Schwartz LM. Screening for cervical cancer: will women accept less? Am J Med. Feb 2005;118(2):151-158.
(3.) Sirovich BE, Welch HG. Cervical cancer screening among women without a cervix. JAMA. Jun 23 2004;291(24):2990-2993.
(4.) Ross JS, Bradley EH, Busch SH. Use of health care services by lower-income and higher-income uninsured adults. JAMA. May 3 2006;295(17):2027-2036.
(5.) Topic Index: A-Z. U.S. Preventive Services Task Force. http://www.ahrq.gov/clinic/ uspstf/uspstopics.htm.
(6.) Nelson HD, Tyne K, Naik A, Bougatsos C, Chan BK, Humphrey L. Screening for breast cancer: an update for the U.S. Preventive Services Task Force. Ann Intern Med. Nov 17 2009;151(10):727-737, W237-742.
(7.) Mandelblatt JS, Cronin KA, Bailey S, et al. Effects of mammography screening under different screening schedules: model estimates of potential benefits and harms. Ann Intern Med. Nov 17 2009;151(10): 738-747.
(8.) Qaseem A, Snow V, Sherif K, Aronson M, Weiss KB, Owens DK. Screening mammography for women 40 to 49 years of age: a clinical practice guideline from the American College of Physicians. Ann Intern Med. Apr 3 2007;146(7):511-515.
(9.) American Cancer Society Prevention and Early Detection. http://www.cancer.org/ docroot/PED/PED 0.asp.
(10.) ACOG practice bulletin. Breast cancer screening. Number 42, April 2003. Int J Gynaecol Obstet. Jun 2003;81(3):313-323.
(11.) Schopper D, de Wolf C. How effective are breast cancer screening programmes by mammography? Review of the current evidence. Eur J Cancer. Jul 2009;45(11):1916-1923.
(12.) Kosters JP, Gotzsche PC. Regular self-examination or clinical examination for early detection of breast cancer. Cochrane Database Syst Rev. 2003(2):CD003373.
(13.) Kyrgiou M, Koliopoulos G, Martin-Hirsch P, Arbyn M, Prendiville W, Paraskevaidis E. Obstetric outcomes after conservative treatment for intraepithelial or early invasive cervical lesions: systematic review and meta-analysis. Lancet. Feb 11 2006;367(9509):489-498.
(14.) Jakobsson M, Gissler M, Sainio S, Paavonen J, Tapper AM. Preterm delivery after surgical treatment for cervical intraepithelial neoplasia. Obstet Gynecol. Feb 2007;109(2 Pt 1):309-313.
(15.) van de Vijver A, Poppe W, Verguts J, Arbyn M. Pregnancy outcome after cervical conisation: a retrospective cohort study in the Leuven University Hospital. BJOG. Feb;117(3):268-273.
(16.) ACOG Practice Bulletin no. 109: Cervical cytology screening. Obstet Gynecol. Dec 2009;114(6):1409-1420.
(17.) Altekruse SF KC, Krapcho M, Neyman N, Aminou R, Waldron W, Ruhl J, Howlader N, Tatalovich Z, Cho H, Mariotto A, Eisner MP, Lewis DR, Cronin K, Chen HS, Feuer EJ, Stinchcomb DG, Edwards BK (eds). SEER Cancer Statistics Review, 1975-2007. http://seer.cancer.gov/csr/1975 2007/, based on November 2009 SEER data submission, posted to the SEER web site, 2010.
(18.) Partridge E, Kreimer AR, Greenlee RT, et al. Results from four rounds of ovarian cancer screening in a randomized trial. Obstet Gynecol. Apr 2009;113(4):775-782.
(19.) Goff BA, Mandel LS, Melancon CH, Muntz HG. Frequency of symptoms of ovarian cancer in women presenting to primary care clinics. JAMA. Jun 9 2004;291(22):2705-2712.
(20.) Goff BA, Mandel LS, Drescher CW, et al. Development of an ovarian cancer symptom index: possibilities for earlier detection. Cancer. Jan 15 2007;109(2):221-227.
(21.) Manson JE, Hsia J, Johnson KC, et al. Estrogen plus progestin and the risk of coronary heart disease. N Engl J Med. Aug 7 2003;349(6):523-534.
(22.) Ridker PM, Cook NR, Lee IM, et al. A randomized trial of low-dose aspirin in the primary prevention of cardiovascular disease in women. N Engl J Med. Mar 31 2005;352(13):1293-1304.
(23.) Walsh JM, Pignone M. Drug treatment of hyperlipidemia in women. JAMA. May 12 2004;291(18):2243-2252.
Laura Davisson, MD, MPH, FACP
Assistant Professor, Department of Medicine, Clinic Director, Center of Excellence in Women's Health, West Virginia University School of Medicine
Table 1. Meta-analysis of mammography screening trials, by age Pooled Age Number of RR for FP per group trials mortality 95% CI NNI 1000 40's 8 0.85 0.75-0.96 1904 98 50's 6 0.86 0.75-0.99 1339 87 60's 2 0.68 0.54-0.87 337 79 NNI = Number needed to invite for screening RR = Relative risk CI = Confidence interval FP = False positive Adapted from Nelson. Ann Intern Med 2009; 151:727-37. Table 2. Mammography screening recommendations USPSTF Routinely begin every 2 years at 50 Individualized decision in 40's ACP Routinely begin at 50 Individualized decision in 40's ACS Annual starting at 40 Continue as long as good health ACOG Every 1 to 2 years in 40's Annual starting at 50 WHO Every 1-2 years Ages 50-69 Canada Every 2 years Ages 50-69 Britain Every 3 years Ages 50-69 Italy Every 2 years Ages 50-69 USPSTF = United States Preventive Services Task Force ACP = American College of Physicians ACS = American Cancer Society ACOG = American College of Obstetrics and Gynecology WHO = World Health Organization Table 3. Breast Self Exam and Clinical Breast Exam Recommendations CBE BSE USPSTF Insufficient evidence to Recommend against teaching address CBE (I statement) BSE (D recommendation) ACS CBE yearly >40 Optional starting at 20 Every 3 years in 20's-30's Inform of benefits/limitations ACOG All women should have annual Lacks definitive data, has CBE potential to detect Can be recommended CBE = Clinical breast exam BSE = Breast self exam USPSTF = United States Preventive Services Task Force ACS = American Cancer Society ACOG = American College of Obstetrics and Gynecology
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