This post is one of several on taking care of your health, and in which I’ll be talking about screening and in a future blog, about prevention (this latter one might be several posts).
The concepts of screening and prevention are related, and sometimes overlapping but different concepts and don’t mean the same things. Screening usually means that one is looking for a disease/disease process that is already occurring. For example, at birth babies are screened for hypothyroidism as well as certain inherited disorders such as phenylketonuria. The disorders screened for may vary a little from state to state but share the traits of having treatments that PREVENT severe disease or complications of the disease (eg, growth retardation and developmental disability in the case of hypothyroidism). As I’m an internist I’ll focus mostly on adult screening. Screening for colon cancer, breast cancer, aortic aneurysm in older people with other risk factors (a history of smoking and/or hypertension, example) can save lives or reduce the burden of disease.
There’s good evidence for screening for cervical cancer with pap smears in women 21 to 65 (early diagnosis can lead to less invasive treatment) every 3-5 years depending on whether it’s done with testing for human papilloma virus testing or not. History is important in the decision as well – a woman who’s had a hysterectomy and her cervix removed as well for something other than cervical cancer is in a different category than is someone with a cervix. Screening for chlamydial infection in young women who are sexually active is another test that has some good evidence behind it (it can lead to PID – pelvic inflammatory disease – which can lead to other issues such as infertility)
For people 50-75 there is good evidence for screening colonoscopy. If a polyp is found it can be biopsied – which if it’s small enough removes the whole thing. In many cases if it turns out to be a pre-cancerous lesion, having removed the polyp removes the chances of it turning into cancer. Often if there is a history of colon cancer in a patient’s family, a screening colonoscopy will be suggested 10 years before the index case occurred. For example if a patient’s mother had colon cancer at age 49, all of her children and siblings should start screening at age 39 not 50. When and what age to start screening is also affected by other familial syndromes as well and to go through all of them is beyond the scope of this particular blog post.
For other screening tests, such as screening asymptomatic males for chlamydial infection, older men for prostate cancer, the evidence is less good for routine screening. As time goes by there will likely be better data to make stronger/more definitive recommendations.
Breast cancer is one area that in the past few years has undergone changes in recommendations. but some organizations recommend recommend screening every two years form 40-50 and then yearly after that. When to start screening and how often is best done in conjunction with your primary care physician.
Screening for proteinuria in patients with hypertension or diabetes might not have the press that some of the screening tests I’ve mentioned (and there are others I haven’t), but can help lead to changing treatment to help prevent or delay kidney disease from getting worse.
For more information you can go to the AHRQ website at http://www.ahrq.gov or the U.S. preventative services website at http://www.uspreventiveservicestaskforce.org
- Which cancer screenings should you skip? Consumer Reports weighs in (boston.com)
- Know What to Expect From Colonoscopy Prep (everydayhealth.com)
- Op-ed: Helping Latinas prevent cervical cancer (nbclatino.com)
- What Is a Precancerous Cervical Lesion? (everydayhealth.com)