The Practice of Preventative Medicine

1. The Practice of Preventative Medicine What tests should we check on our patients and when should we check them?

2. Outline • What is preventative medicine and what is it’s importance • The definition of screening and how we decide what a good screening test is • Who do you look to for the current recommendations, and how do they formulate those recommendations • The tests/procedures and current recommendations

3. What is preventative medicine? • Disease prevention • Identification of disease at an early stage • Definition: procedures/exams/interventions performed on patients without specific complaints, to identify and modify risk factors to avoid the onset of disease, or to find disease early in its course so that by intervening patients can remain well. • Synonyms: health maintenance or the periodic health examination

4. What is the importance of reviewing this subject. • 1. It has been shown to be effective at many levels (ex. Community wide immunizations, colorectal cancer screening, cervical cancer screening, breast cancer screening, etc..) • 2. Your patients are going to ask you questions about why you are checking certain tests. (ex. Pap smear, mammograms) • 3. Cost considerations (if a test is not shown to be beneficial, then by checking it routinely we are wasting resources)

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6. 3 levels of preventative medicine • 1. Primary prevention- prevents disease from occuring at all by removing it’s causes (ex. Use of folic acid to prevent neural tube defects, immunizations, counseling to adopt healthy lifestyles, mandating seat belt use, etc..) • 2. Secondary prevention- detects disease early when it is asymptomatic and when early treatment can stop it from progressing (ex. Pap smears, mammograms, FOBT, colonoscopy, etc..) • 3. Tertiary prevention-clinical activities that prevent further deterioration or reduce complications after a disease has declared itself ( ex. Starting BB after MI to decrease risk of death, initiation of ACE-I in diabetics to prevent nephropathy, etc.)

8. Screening • The identification of unrecognized disease using various modalities (H/P, lab tests, Xray, procedures) • Sort out well appearing persons with a disease or risk factors for disease • Part of many primary and all secondary prevention measures • Screening tests are typically not diagnostic so the clinician must be willing to further investigate a + test

9. How do we decide what to screen for? • 1. Must consider the burden of suffering caused by the condition (discomfort, disability, death) • 2. Must consider how good the screening test is in terms of sensitivity, specificity, cost, ease of use, safety, acceptability, risk of a false positive, labeling of pts with conditions. • 3. Then must consider in the case of primary prevention, how good is the intervention in preventing the disease, or in secondary prevention , how good are the treatments that are available for the disease (in terms of efficacy/compliance/early treatment as a benefit versus late treatment)

10. What does that mean? • Example: Breast cancer screening • Primarily occurs in women >50yrs • In women in their 20’s the incidence is very low approx 1 in 100,000 • For the women that get breast CA at that age there is a substantial morbidity and mortality, but given it’s rarity in that age group screening becomes impractical and would probably lead to more morbidity and usage of resources from further w/u of false positives (biopsies, further radiological tests, etc..)

11. The dreaded Statistics • A good screening test should have a high sensitivity to limit the false negatives and a high specificity to limit the false positives (these are affected by the prevalence of the disease in the population). • For many screening tests the gold standard from which sens/spec are determined is based on long term follow up with monitoring for occurrence of a disease following the screening test -detection method. The two problems with this are knowing the length of time needed to follow the patient to detect the disease, and the assumption that the abnormality detected would go on to cause disease if left alone (ex. Estimated that virtually all men >90yr have foci of prostate CA). A second method to get around this is the incidence method which calculates sensitivity based on ratio of pts with a disease undergoing the screening test over that of the patients with the disease who don’t have the test (1- pts with disease undergoing screening/ pts with disease who didn’t have screening). This limits counting benign conditions found on screening but might decrease sensitivity by ignoring pts with malignancies with long lead times.

12. Consider Simplicity and Cost • A good screening test should be relatively simple to perform (ex. BP) although that is not always the case (colonoscopy) • Cost of not only the test itself, but the cost of subsequent workups of positive results and the time missed from work for special visits to the physician must be considered

13. Acceptability, Labeling • Acceptability- Do the pt and physician find the test acceptable to perform (ex. Many asymptomatic pts refuse a colonoscopy, many women refuse pelvic exams) • Labeling- Psychologically a false positive result can be devastating for a pt. One study showed that almost 50% of women with false + mammograms read as high suspicion suffered anxiety and worries that affected their daily lives (1).

14. Risk of False Positives • One study showed that on average internists selected 54 different tests during periodic health examinations (components of CBC, Chem 14 etc.) (2).

15. Biases • Lead time bias- Period of time between detection of disease by screening versus when it would present with symptoms. If the period is very short then the screening test will not be very useful (ex. Lung cancer). If the lead time is long then the test might be useful (ex. Cervical CA). • Length time bias- more slow growing cancers are diagnosed during screening than during usual medical care when pts are more likely diagnosed with a rapid growing tumor causing symptoms, so screening may be catching more malignancies with a better prognosis and therefore might appear more beneficial than it truly is.

17. Where do you look for the current recommendations? • The U.S. Preventative Services Task Force (USPSTF) was first convened by the U.S. Public Health Service in 1984 and it’s recommendations are considered the gold standard for clinical preventative services. They review the current available literature/information and make recommendations based on the available data. • They have released two print editions and portions of the 3rd edition are now available online.

18. H/P and Labs H&P CBC CHEM 8 LFT’s Fasting Lipids TSH PSA UA PAP Smear HIV Serology FOBT Radiological/Procedural Colonoscopy Mammogram EKG/Stress testing/Calcium scores CXR DEXA Ankle/Brachial Index (PAD) Carotid Doppler The tests that I will review

19. How do they rate these tests? • First they rate the evidence • Prior to the 3rd edition • Grade I-at least one properly randomized controlled trial • Grade II-obtained from other controlled trials or analytic studies, or from multiple time series with dramatic results in uncontrolled experiments, has 3 subcategories based on the type of study • Grade III-Opinions of respected authorities based upon clinical experience, descriptive studies and case reports, or reports of expert committees. • With the 3rd edition they tried to simplify it • Good- consistent results obtained from well designed, well conducted studies in the representative population that directly assess effects on health outcomes • Fair- evidence sufficient to determine effects on health outcomes but the strength of evidence is limited by the number, quality, or consistency of individual studies, generalizability to routine practice, or indirect nature of the evidence on health outcomes. • Poor-evidence is insufficient to assess the effects on health outcomes because of limited number or power of studies, important flaws in design or concept of studies, gaps in the chain of evidence, or lack of information on important health outcomes.

20. Next they give a recommendation and grade the recommendation based on that evidence • Prior to 3rd edition there were 5 grades • A-There is good evidence to support the recommendation for inclusion of the service for the periodic health evaluation. • B-There is fair evidence to support the recommendation for inclusion of the service for the periodic health evaluation. • C-There is insufficient evidence for or against the recommendation for inclusion of the service for the periodic health evaluation. • D-There is fair evidence to support the recommendation to exclude the service for the periodic health evaluation. • E-There is good evidence to support the recommendation to exclude the service for the periodic health evaluation. • For the 3rd edition USPSTF changed grading to include recommendations • A-USPSTF strongly recommends the clinician provide the service to eligible pts, because there is good evidence it was found to improve important health outcomes and concludes that benfits outweigh the harms • B-USPSTF recommends the clinician provide the service to eligible pts, because there is fair evidence it was found to improve important health outcomes and concludes that benfits outweigh the harms • C-USPSTF makes no recommendation for or against the service, because there is fair evidence it can improve health outcomes but balance of benfits and harms is too close for a general recommendation • D-USPSTF recommends against the service for asymptomatic pts, because there is fair evidence it is ineffective or that harms outweigh benefits • I-The evidence is insufficient to recommend for or against the service

21. History and Physical • No general recommendation for or against general H/P and the only thing it costs is time • Obviously a thorough H/P on initial consultation and then periodically is the best screening tool that we have since the majority of our diagnoses are made through H/P • Certain aspects that do have recommendations

22. Blood Pressure • For pts age ≥18: Grade A with good evidence for regular screening for HTN (at least every one to two years)

23. Clinical Breast Exam • Grade-I :no study comparing CBE to no exam, and studies show that breast cancer mortality is similar in groups screened with mammography +/- CBE, most organizations including the AMA recommend to begin yearly exams starting at age 40 (if not earlier based on family history)

24. Digital Rectal Exam • Grade I: Although DRE has some utility as a screening tool for prostate CA (although sensitivity is still quite low) it is inconclusive whether early detection improves outcomes and screening is associated with important harms (frequent false +, anxiety, biopsies etc.). None of the major medical societies endorses universal or mass screening of any particular group, but they conclude that men most likely to benefit are ≥age 50 (or younger if they have a strong family history) and have a life expectancy of >10yrs.

25. CBC • No general recommendation on a complete blood count • For H/H- Grade C (2nd edition) with level I/II evidence which is inconclusive, so no rec. for or against general use as screening tool. For Pregnant women – Grade A with level I/II evidence for screening

26. Chemistry Panel • No general recommendation on total chem panel • Glucose- • In general population-Grade I, not enough evidence available to recommend for or against screening • In patients with HTN or hyperlipidemia- Grade B with good evidence for annual screening since in pts with HTN and hyperlipidemia there is a higher level of DM II and that those pts benefit from more aggressive treatment of their HTN/hyperlipidemia

27. Liver Function Tests • No general recommendations to use as a screening tool • There are recommendation for Hep viral screening • Hep B surface antigen • In pregnant women at first prenatal visit- Grade A with good evidence for screening all pregnant women • In general asymptomatic pts- Grade D with no evidence of benefit and possible harms (cost, labeling, etc.) • In high risk pts- Grade C, no recommendation for or against, might be beneficial to identify pts that might benefit from vaccination • Hep C serology • In general population- Grade D, with no evidence of benefit and possible harms • In high risk pts- Grade I, In high risk pts screening would have higher yield and tx with current therapies appear beneficial but no data as to whether early tx improves mortality (although older therapies are suggestive that it does) so they were unable to give a general recommendation for or against, but other groups including the NIH/CDC do recommend screening high risk groups

28. Lipids • For Men age ≥35 and Women age ≥45- Grade A with good evidence for screening every 5 years • For men/women less than those ages with other risk factors for CAD- Grade B with good evidence for screening every 5 years • For men/women less than those ages without risk factors for CAD- Grade C with no good evidence for or against screening although potential benefit in this pt population is likely less

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30. TSH • In Asymptomatic pts- Grade I, no recommendation for or against regular screening since there is no substantial data showing benefit to treating subclinical screening detected thyroid disorder

31. PSA • Pts of any age- Grade I, no recommendation for or against use as a regular screening test for similar reasons to DRE. Must discuss risks/benefits of the test with pt and decide together whether to proceed.

32. UA • For Asymptomatic men/women (not pregnant)- Grade D with fair evidence that there is no benefit to routine screening • Pregnant women- Grade A, recommends routine UA/Culture at 12-15 wks to r/o asymptomatic bacteruria • As a screen for bladder CA- Grade D with fair evidence that screening is not beneficial due to the low prevelance of asymptomatic disease that progresses to clinically significant disease

33. PAP Smear/Pelvic • Women who are sexually active and have a cervix- Grade A with good evidence for beginning screening pap smears at least every 3 yrs within 3yrs of onset of sexual activity or by age 21. There is no direct evidence that yearly screening is more effective, but several organizations have made recs. regarding yearly screening till 2 to 3 normals followed by screening every 3 yrs, or yearly testing in pts with higher risk sexual activity, although there is no data to support either of these recs.. • Women ≥65 with adequate normal pap smears recently and at not at high risk- Grade D with limited evidence for benefit with cont screening in this population • Women who had hysterectomy for benign disease- Grade D with fair evidence that there is little benefit to cont screening in the population • HPV testing- Grade I with poor evidence to determine the risks/benefits of HPV testing in conjunction with pap smear as a screening tool. Trials are ongoing looking at question, but currently no recommendation for or against it’s use.

34. HIV Serology • History is very important on deciding this issue • In non high risk groups- Grade C recommendation with fair evidence , no recommendation for or against screening • In high risk groups (IVDU, homosexual men)- Grade A with good evidence for periodic screening • For Pregnant women- Grade A with good evidence for routine screening

35. FOBT/Colonoscopy • Recommends screening for CRC in general with Grade A, good evidence that screening beginning at age 50 for average risk individuals is beneficial. They do not make direct recommendations on which screening modality to use although they suggest multiple possibilities including yearly FOBT + flexible sigmoidoscopy every 5 yrs, or colonoscopy every 10 yrs (considered the gold standard) that vary in their cost, complications, availability, sensitivity/specificity etc.. • For pts with a FH of colon CA before age 60 it is reasonable to begin screening at an earlier age

36. Mammogram • For women age ≥40- Grade B recommendation with fair evidence of benefit for screening with mammogram every 1-2 yrs with or without CBE/SBE

37. EKG/Stress testing/Calcium Scores • In pts at low risk for CHD events- Grade D recommendation with fair evidence that although testing will detect a small percentage of pts with disease, the harm from screening the population including unnecessary procedures/over treatment/labeling outweigh any benefits • In pts at increased risk for CHD- Grade I with insufficient evidence to recommend for or against screening in this population. It is unclear in a asymptomatic pt in this population whether these tests add more information than risk stratification based on conventional CHD risk factors, and whether the benefits outweigh the harms. (the AHA suggests stress testing might be beneficial for diabetic pts if they are going to start a vigorous exercise program).

38. CXR • To screen for Lung CA- Grade I with insufficient evidence to recommend for or against routine screening (there is no good study designed to look at screening versus not screening, but observational studies suggest that CXR screening does not decrease mortality from lung CA which makes since because by the time it is visible on a CXR it has usually metastasized on a cellular level and we have essentially no effective treatment options for metastatic disease).

39. DEXA (Dual-energy x-ray absorptiometry ) • Women age ≥65 or women between 60-64 who are at increased risk (low wt, postmenopausal not on estrogen replacement)- Grade B recommendation with good evidence that screening is beneficial in these groups of women. There is no specific recommendation on the screening interval, but it is thought that 2 yrs might be needed to see a substantial difference in BMD. • Women age 60-64 who are not at increased risk or women younger than 60- Grade C with fair evidence that it would prevent a small number of fractures but the benefits and harms were similar so no recommendation for or against screening in this population • Women/Men on long term corticosteroids- Not specifically reviewed. A summary statement by the Amer College of Rheum in 2001 recommended that for Pt on Prednisone≥ 5mg daily for time of ≥3months that they be screened annually to biannually (and tx preventatively)(3). • Screening in Men- has not been reviewed to date

40. Ankle/Brachial Index • In Asymptomatic Individuals- Grade D with fair evidence that pts in this category would not benefit from screening/treatment

41. Carotid Doppler • In Asymptomatic Individuals- Grade I with insufficient evidence for screening with carotid doppler in this population

42. Men Annual H&P starting at age 18 including BP measurement Fasting Lipids every 5 yrs starting at age 35 for average risk pts and younger if pt has significant risk factors CRC screening starting at age 50 with either annual FOBT with flex sig every 5 yrs or colonoscopy every 10 yrs. If Pt has FH of early CRC then it is acceptable to begin screening at a younger age (dictated by their history) If pt has HTN or Hyperlipidemia then check annual fasting glucose HIV Serology annually in high risk populations Women Annual H&P starting at age 18 including BP measurement Fasting Lipids every 5 yrs starting at age 45 for average risk pts and younger if pt has significant risk factors CRC screening starting at age 50 with either annual FOBT with flex sig every 5 yrs or colonoscopy every 10 yrs. If Pt has FH of early CRC then it is acceptable to begin screening at a younger age (dictated by their history) If pt has HTN or Hyperlipidemia then check annual fasting glucose HIV Serology annually in high risk populations Pap Smear every 1-3 yrs (no good evidence to support one way over another) starting within 3 yrs of initiation of sexual activity or by age 21. Mammogram annually starting at age 40 DEXA biannually starting at age 65 for normal risk pts or age 60 for higher risk pts H/H, Glucose, Hep B sur Ag, UA/Culture, and HIV serology all recommended in pregnant women Summary: What you should definitely do

43. Men DRE +/- PSA annually starting at age 50 in men with a 10 yr life expectancy Annual fasting glucose in pts without risk factors Lipids in pt less than 35 yrs old without CAD risk factors TSH HIV screening in low risk individuals Hep B/C screening in high risk individuals CXR in long term smokers to screen for lung CA DEXA (no recommendation to date) EKG +/- Stress testing for asymptomatic pts with multiple risk factors for CAD (including DM) Women Annual fasting glucose in pts without risk factors Lipids in pt less than 45 yrs old without CAD risk factors TSH HIV screening in low risk individuals Hep B/C screening in high risk individuals CXR in long term smokers to screen for lung CA DEXA in pts less than 60 yrs old EKG +/- Stress testing for asymptomatic pts with multiple risk factors for CAD (including DM) HPV testing in addition to PAP Smear Screening tests that the evidence is inconclusive or not available

44. Tests Not recommended for screening • CBC/CHEM8/LFT’s • ABI • PAP/Pelvic for pts who had hysterectomy secondary to benign disease, or for women 65yrs or older who have had negative pap smears on regular routine screening • Carotid Dopplers • Hep B/C serologies • UA (for bladder CA or other etiologies)

45. Bibliography • 1. Lerman, C, Trock, B, Rimer, BK, et al. Psychological and behavioral implications of abnormal mammograms. Ann Intern Med 1991; 114:657. • 2. Romm, FJ, Fletcher, SW, Hulka, BS. The periodic health examination: Comparison of recommendations and internists' performance. South Med J 1981; 74:265. • 3. Recommendations for the prevention and treatment of glucocorticoid-induced osteoporosis: 2001 update. American College of Rheumatology Ad Hoc Committee on Glucocorticoid-Induced Osteoporosis. Arthritis Rheum 2001 Jul;44(7):1496-503. [54 references] • 4. www.ahrq.gov/clinic/prevnew.htm. • 5. www.uptodate.com, Preventive services recommendations for periodic health evaluation, F. Daniel Duffy, MD