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New Pap smear schedule led to fewer chlamydia tests, new U-M study suggests

But adding reminder in clinic computers ensures young women get both recommended health screens at the right time

ANN ARBOR, Mich. — It’s a tale of two tests: one for early signs of cervical cancer, the other for a sexually transmitted disease. But a new study suggests that a change in the recommended schedule for one may have dramatically lowered the chances that young women would get the other. 

Results published by a University of Michigan team shows the unintended consequences of changes to national health test guidelines: the potential for doctors to fall behind on ordering other tests that screen for serious health problems. 

In this case, the two tests are Pap smears and screens for the most common sexually transmitted disease: chlamydia. If undiagnosed, chlamydia can leave women in pain, infertile or unable to have a successful pregnancy.  

Until six years ago, recommendations for most women under age 25 called for Pap smears earlier and more often, and chlamydia screening once they were sexually active. Doctors could take samples during the same pelvic exam. But the Pap smear schedule for young women changed in 2009, removing annual tests before age 21 to reduce the chance of unneeded follow-up tests.

Dr. Allison Ursu

Allison Ursu, M.D.

“With the change in screening, we wanted to see if there were other implications, and indeed a decrease in chlamydia screening occurred even though the number of visits by young women was about the same,” says U-M Medical School Department of Family Medicine lecturer Allison Ursu, M.D., the lead author of the new paper in Annals of Family Medicine.

She and her colleagues looked at the tests given to sexually active young women aged 16 to 21 years with no chlamydia symptoms who came to U-M’s five family medicine clinics in the year before the new Pap test guideline and two years later. Those in the earlier group were nearly 14 times more likely to get a chlamydia test than those seen later, even though there was no drop in clinic visits by such patients.

The five clinics have since added a reminder into their shared computer system to prompt doctors to order a chlamydia test once a year for sexually active, asymptomatic young women. A urine test for chlamydia is also available, so doctors don’t need to perform a pelvic exam.

The sharp drop in testing at the U-M clinics suggests that the Pap smear guideline change could have had the same effect elsewhere. The team hopes their findings will prompt other primary care clinics to assess whether they need to pay attention to ensuring chlamydia testing is done on time, even if it’s not paired with a Pap test. 

Their results showed that a U-M family medicine clinics, the two were performed together 60 percent of the time before the guideline change, but only 10 percent of the time two years later. 

Says Ursu, “The clinical framework of the visit shifts when we’re not doing a pelvic exam, and the things we’re thinking about are different.” 

Need for better attention to chlamydia testing 

Annual chlamydia tests are recommended for all sexually active young women under age 25, because the disease can be silent for years and can be transmitted by partners symptoms. Early detection and treatment with antibiotics can prevent long-term effects such as pelvic inflammatory disease that can affect the fallopian tubes and lead to infertility or ectopic pregnancy. 

The state of Michigan recently approved expedited partner therapy, which allows doctors to prescribe antibiotics to the partner of a patient who screens positive for chlamydia even if they’re not seen in the same clinic.

National data show that only about two of every five young women nationwide get screened for chlamydia on the recommended schedule. 

Guidelines for screening tests are set by national groups for particular medical specialties, based on the latest evidence from research that balances benefit and potential for harm. It can take time for doctors nationwide to begin following guidelines, and some may choose to go against them for other reasons. But insurance companies usually pay for screening tests recommended by major specialty groups. 

But new computer systems increasingly in use at clinics can be set to prompt medical assistants, doctors and nurses during a visit for the tests recommended for each patient. 

The new reminder in the MiChart system in use across all of the U-M Health System’s primary care clinics has greatly increased chlamydia screening for teen and young adult women.  Now, more than two-thirds of sexually active patients with no symptoms get screened each year. Further analysis will look at impacts on chlamydia infections, PID cases and ectopic pregnancies seen among UMHS patients. 

Senior author and U-M professor of family medicine Mack Ruffin, M.D., MPH, says, “Patients are very aware of Pap tests and many still think they need one yearly. There’s much less awareness of chlamydia screening. The takeaway from this study is that we have to find other opportunities to screen.” 

Ruffin is a member of the U-M Institute for Healthcare Policy and Innovation and is the Max and Buena Lichter Research Professor in the Department of Family Medicine. Co-author Ananda Sen, Ph.D. is the Lee A. Green Collegiate Research Professor in Family Medicine. Both Ruffin and Sen hold joint positions in the U-M School of Public Health.

Reference: Annals of Family Medicine,, Vol. 13, No. 4, July/August 2015



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