Increasing Chlamydia Positivity among Women Attending Region X Family Planning Clinics, 1997-2004: Is NAAT Testing the

1. Increasing Chlamydia Positivity among Women Attending Region X Family Planning Clinics, 1997-2004:Is NAAT Testing the Reason? Fine D1, Mosure DJ2, Dicker LW2, Berman S2 1 Center for Health Training, Seattle, WA 2 Division of STD Prevention, Centers for Disease Control and Prevention Atlanta, GA

2. Region X Chlamydia Project In 1988, the first widespread screening and treatment program for chlamydia began in four states--Alaska, Idaho, Oregon and Washington (U.S. Public Health Service Region X) Focused on screening all young sexually active women seen in 150 family planning clinics (about 50,000 women per year) Implemented the first chlamydia prevalence monitoring surveillance system using standardized laboratory testing and data collection Became the basis for the National Infertility Prevention Program

3. Chlamydia trends in positivity in 15-24 year old women screened in family planning clinics Region X, 1988-1996 65% decrease in positivity from 1988-199665% decrease in positivity from 1988-1996

4. Chlamydia trends in positivity in 15-24 year old women screened in family planning clinics Region X, 1988-2004 51% increase from 1996-2004 51% increase from 1996-2004

5. Objective To assess trends in risks associated with chlamydia positivity in women aged 15-24 years seen in family planning clinics from 1997-2004

6. Methods All women aged 15-24 years screened for chlamydia 125 family planning clinics from 1997-2004 participated in the project all 8 years screened at least 50 women per year 500,126 chlamydia tests The same medical record was used by all clinics to collect: Demographics Clinical findings MPC Friable cervix Ectopy PID Self-reported sexual risk behavior history (last 60 days) new sex partner multiple sex partners symptomatic partner Represents >88% of all testsRepresents >88% of all tests

7. Analysis Assessed trends in the prevalence of clinical findings and self-reported behavioral risk Calculated chlamydia positivity by demographics, behavioral risk history, and clinical findings Adjusted positivity trends for changes in laboratory test method1 Multivariate models were used to assess changes in clinical and behavioral risk factors and test type

8. Did the population of women visiting family planning clinics change? Age distribution remained stable except for percent of women age < 18 screened which decreased from 24.2% (1997) to 18.7% (2004) Race distribution remained stable: White 76.6% (1997) and 74.9% (2004) Same clinic sites all 8 years Number of women screened remained constant Impact on trend: chlamydia positivity should decrease if there were fewer high risk women being screened

9. Proportion of women reporting sexual risk behaviors 12% decrease in women having a new partner 14% decrease in women having multiple partners 4% decrease in women with a symptomatic partner 14% decrease in women with 1 or more clinical findings

10. Did laboratory test type change? Amplified chlamydia test (NAATs) use increased from: 13.4% in 1997 59.5% in 2004 Now, it�s mostly Genprobe�s Target Capture,Transcription-Mediated Amplification test Earlier years there were othersNow, it�s mostly Genprobe�s Target Capture,Transcription-Mediated Amplification test Earlier years there were others

11. Is NAATs testing the reason for the increase in chlamydia positivity? This is the same data that was in the bar graph at the beginning of the talk. Points represent a mixture of test typesThis is the same data that was in the bar graph at the beginning of the talk. Points represent a mixture of test types

12. Chlamydia trends in positivity in 15-24 year old women screened in family planning clinics Region X, 1997-2004 Thus we tried to standardize over time. Adjusted for laboratory test type for sensitivity and specificity. Adjustment brings us closer to the �true� positivity However, we are dependent on getting the sensitivity and specificity correct. So, not have to worry about the adjustment� Thus we tried to standardize over time. Adjusted for laboratory test type for sensitivity and specificity. Adjustment brings us closer to the �true� positivity However, we are dependent on getting the sensitivity and specificity correct. So, not have to worry about the adjustment�

13. Chlamydia trends in positivity in 15-24 year old women screened in family planning clinics Region X, 1997-2004 We looked at the trend for NAATs only (Green) � so we didn�t have to worry about the adjustment. NAAT trend line close to the adjusted line because of the increased sensitivity, suggesting getting pretty close to the �truth� The main point � the increasing trend is not because we didn�t adjust correctly, that positivity for NAAT line only is still going upWe looked at the trend for NAATs only (Green) � so we didn�t have to worry about the adjustment. NAAT trend line close to the adjusted line because of the increased sensitivity, suggesting getting pretty close to the �truth� The main point � the increasing trend is not because we didn�t adjust correctly, that positivity for NAAT line only is still going up

14. Main point: there is a very slight difference in the slope � essentially the same slope for increasing risk of CT over time, for NAATs and non-NAATS Suggesting that even if only NON-NAATs test were used, there would still be an increase in chlamydia positivity over timeMain point: there is a very slight difference in the slope � essentially the same slope for increasing risk of CT over time, for NAATs and non-NAATS Suggesting that even if only NON-NAATs test were used, there would still be an increase in chlamydia positivity over time

15. Question: Is NAAT testing the reason for the increase in chlamydia? Answer: Not entirely Steady increase in true prevalence which some is accounted for by changing tests, BUT NOT ALLSteady increase in true prevalence which some is accounted for by changing tests, BUT NOT ALL

16. Risk of chlamydial infection in women aged 15-24 years Region X family planning clinics, 1997- 2004 Characteristic Adj. OR* Age group (years) 15-19 1.37 20-24 Ref. Race/Ethnicity White Ref. Non-White 1.59 Clinic city size (persons) >25,000 Ref. 25,000-99,999 1.15 ?100,000 1.18 *Adjusted odds ratios based on multivariate analyses New analyses post-1995 ISSTDR Identified measures independently associated with CT positivityNew analyses post-1995 ISSTDR Identified measures independently associated with CT positivity

17. Risk of chlamydial infection in women aged 15-24 years Region X family planning clinics, 1997- 2004, cont. Characteristic Adj. OR* 1+ behavioral risks 1.95 SP with chlamydia 3.87 No condom, last sex 1.16 Clinical signs 2.92 Positive CT, past year 1.79 Chlamydia test type NAAT 1.36 Non-NAAT Ref. Year of visit 1.05 Key point: Year of Visit shows slight positive relationship. Also, did analyses at state level and for large/small clinics and rural/urban�Year of Visit remains a predictorKey point: Year of Visit shows slight positive relationship. Also, did analyses at state level and for large/small clinics and rural/urban�Year of Visit remains a predictor

18. Next Steps Consider how to evaluate influence of other aspects of sexual risk that we did not collect data on, e.g., history of condom use, partner risk, type of treatment Evaluate changes over time in FP clinic screening coverage among young adult women Assess changes in FP client populations, e.g. proportion of continuing patients, SES trends Evaluate chlamydia positivity trends in venues and populations outside of Region X FP clinics, e.g., prenatal, community health centers, STD clinics, males Explore comparable FP analyses in other Regional Infertility Prevention Projects around the country

19. For more information, contact: David Fine, Ph.D. Center for Health Training 1809 Seventh Avenue, Suite 400 Seattle, WA 98101-1313 206/447-9538 tel 206/447-9539 fax dfine@jba-cht.com