Among adult women, CA FP setting has relatively low CT rate

1
Developing CT Screening Guidelines for Women gt25
The Over 20 Study The Over 25 Evaluation
Region II IPP Meeting NYC, NY May 17, 2007
2

• An evaluation of the performance/appropriateness
  of national chlamydia (CT) screening guidelines
  when applied to non-pregnant adult women seeking
  family planning services in California.

3
Background The Problem

• Excessive CT screening in populations with low
  CT morbidity has implications
• Not an effective use of limited resources
• CA uses 3 as cost-effective cut-off
• May lead to a higher proportion of false positive
  test results

4
Background The Problem (CA)

• Among adult women, CA FP setting has relatively
  low CT rates but high volume of screening
• Significantly less CT in women age gt25 than in
  younger women, yet screening rates are similar
• Almost 50 of all screening occurs in this older
  age-group
• CT prevalence in this population gt25 is lt3
• CT rates for women age 21-25 lt3 in some areas

5
Background Why Not Stop Screening Older Women
Altogether?

• Detecting/treating CT infections has been shown
  to reduce such adverse sequelae as PID,
  infertility
• The vast majority of CT infections in all women,
  including women gt25, are asymptomatic or
  silent
• Over 70 of CT in women gt25 do not present with
  clear clinical indications for testing
• Screening is the only effective mechanism for
  detecting silent infections
• No Screening Missing gt70 of CT in this
  population

6
Background The Solution Targeted Screening
TS!

• Evidence-based targeted screening strategies
• Can identify a sub-population with higher CT
• A balance between saving resources and still
  reducing the burden of CT in lower-prevalence
  populations

7
BackgroundWho to Target?

• Clear guidelines needed to target CT screening in
  adult women
• Though national recommendations support targeted
  screening for women gt25, they are
• Not well-defined
• Inconsistent, and/or
• Inefficient

8
The Over 20 Study
9
The Over 20 StudyResearch Objectives

• Among non-pregnant women age 21-30 seeking family
  planning services
• Determine predictors of CT infection
• Develop efficient targeted screening strategies
  for CT infection, specifically in women gt25
• Determine whether targeted screening is
  appropriate for the population of women 21-25

10
The Over 20 StudyStudy Methods
Study Design Cross-sectional

• Patient Eligibility Criteria
• Female clients seeking FP services
• Age 21-30
• Not pregnant
• Sexually Active (self-report of vaginal sex in
  past 12 months)

11
The Over 20 StudyStudy Methods

• Data collected methods
• Self-administered patient questionnaires
• Demographics, relationship status, sexual
  behavior, STD history
• Clinician-completed clinical evaluations
• Reason for visit, birth control, STD contact, STD
  history, symptoms, clinical signs diagnoses,
  presumptive CT/GC Rx
• Laboratory databases
• CT GC test results

12
The Over 20 StudyResults Participating Agencies
Project Timeline

• Participating Sites
• 9 clinics (3 CA FP agencies) all performing
  universal screening
• Timeline two phases
• May 2003 to May 2004
• August 2004 to November 2005

13
The Over 20 StudyResults Final Study
SampleStudy Forms Submitted forUnique,
Eligible, CT-Tested Clients and Successfully
Matched with Lab Result Data
Age 21-30 years
14
The Over 20 Study Total Sample Results
DemographicsAge (Years)
CT Tested N 4,292
15
The Over 20 Study Total SampleResults
DemographicsRace/Ethnicity
CT Tested N 4,292
16
Patients with Clinical Indications for CT Testing
excluded from screening analysis

• Report of current contact (exposure) to an STD
• CT-indicative clinical syndrome diagnosed on
  exam
• Cervicitis endocervical discharge, cervical
  friability, or cervical inflammation
• Pelvic inflammatory disease (PID)
  Adnexal/uterine tenderness or cervical motion
  tenderness
• New STD (confirmed or presumptively treated)
  diagnosed in-office on day of visit
  (trichomoniasis presumptive HSV, GC, or genital
  warts syphilis, HIV)

17
The Over 20 Study Results (Age 21-30) CT
Prevalence Proportion of Cases by Clinical
Presentation Exclusion Criteria Applied to
Screening Analysis
Total CT-tested Participants N 4,292 nCT
180 4.2 CT

• Patients with clinical
• indications for CT testing
• N 550 nCT 48
• STD contacts
• Cervicitis or PID
• New STD dx
• 8.7 CT

• Patients screened for CT
• N 3,742 nCT 132
• No STD contact
• No cervicitis or PID
• No new STD dx
• 3.5 CT

27 of CT Cases
73 of CT Cases
87 of Pop. Tested
13 of Pop. Tested
18

• Patients screened for CT
• N 3,742 nCT 132
• No STD contact
• No cervicitis or PID
• No new STD dx (except GC)
• 3.5 CT

Patients age 21-25 screened for CT N 2655
nCT 100 3.8 CT
Patients age 26-30 screened for CT N 1,087
nCT 32 2.9 CT
19
The Over 20 StudySummary of Univariate
FindingsWomen age 26-30 years

• Risk factors predictive or protective for CT
  infection (statistically significantly)
• Partners possible other partners (3 or 12 mos)
• More than 1 or 2 partners (3 or 12 mos)
• BV
• Married
• Stable relationship (married, engaged or living
  with partner)
• New partner in past 3 mos (p-value 0.06)

Protective against CT infection in univariate
analysis Independently associated with CT in
multivariate analysis (p-value lt0.05)
20
The Over 20 StudyPartner possible other
partnersActual Question Studied

• Q At anytime within the past 12 months, did any
  of your male partners have sex (of any type) with
  someone else while they were still in a sexual
  relationship with you?
• A ? Yes, definitely
• ? Not sure, it is possible
• ? No, it is very unlikely

Answers combined
Also asked about the past 3 months in a
separate question.
21
The Over 20 Study Screening AnalysisResults
Performance of Selective Screening
AlgorithmsAge 26-30
22
The Over 20 Study Screening AnalysisResults
Performance of Selective Screening
AlgorithmsAge 26-30
Approximate replication
23
The Over 20 StudyKey Study Limitations

• Convenience sample of clinics mostly located on
  Californias central coast and in the central
  valley -- may not be representative of overall CA
  FP population
• Unknown if results applicable to women gt 30

24

• The Over 25 Evaluation
• IPP Scantron Data
• Chart Abstraction

25
The Over 25 Evaluation IPP Scantron
DataBenefits Strengths

• Can use existing IPP data collected via Scantron
  forms (3,000) from CA Project Area and Los
  Angeles CT prevalence monitoring sites
• Scantron forms newly revised 7/06 with influence
  from Over 20 Study result similar data
• CPA and LA Scantron forms now identical
• 20 geographically diverse clinic sites across
  CA
• Data collected from CT-tested patients of all ages

26
The Over 25 Evaluation IPP Scantron Data
Challenges Limitations

• Needed some supplemental data not available on
  forms (e.g., BV status)
• Forms had never been validated
• Clinic sites already targeting CT screening in
  women gt age 25 -- data bias
• May give inflated prevalence rates
• May underestimate associations between risk
  factors and CT
• of population screened in algorithms may not be
  accurate

27
The Over 25 Evaluation Chart AbstractionDesign/M
ethods

• Design Case-Control Chart Abstraction
• Use Scantron forms to pull sample of medical
  record charts for abstraction
• All CT-positive patients (100)
• A random-sample of CT-negative patients, chosen
  by clinic site, using a 4 negatives1 positive
  ratio (400)
• Collect supplemental data for research purposes
• Collect identical data, as possible, for
  validation purposes

28
The Over 25 Evaluation IPP Scantron
DataValidation Results

• Successfully abstracted 82 of sample goal
  (446/544 charts in total 83/100 CT charts)
• 8 pregnant
• 1.5 males
• Other issues wrong DOBs out of eligible age
  range clients not tested for CT missing charts
• Data concordance
• Demographics/other core variables gt 90
• Lab data gt 95
• CT symptoms 96 of Nos / 33 of
  Yess
• Clinical data 96 of Nos / 38
  of Yess
• Behavioral data 60-97 of Nos / 38-60 of
  Yess

29
Summary of Study Differences
Over 20 Study
Over 25 Evaluation
30
CA Chlamydia Rates by County, 2005
Over 20 Over 25Site Distributions
7/2006 Provisional Data - CA DHS STD Control
Branch
31
The Over 25 Evaluation Total Weighted Chart
Abstraction Sample Results Total Sample Age
(Years)
CT Tested N 2,634
32
Results Total Samples Race/Ethnicity
CT Positives
CT Tested
Over 20 Study
N 4,292
n 180
Over 25 Evaluation Weighted sample
N 2,616
n 83
33
The Over 25 Evaluation Results (Age 26-44) CT
Prevalence Proportion of Cases by Clinical
Presentation Exclusion Criteria Applied to
Screening Analysis
Total CT-tested Participants N 2,634 nCT
83 3.2 CT

• Patients with clinical
• indications for CT testing
• N 346 nCT 24
• STD contacts
• Cervicitis or PID
• New STD dx
• 6.9 CT

• Patients screened for CT
• N 2,287 nCT 59
• No STD contact
• No cervicitis or PID
• No new STD dx
• 2.6 CT

29 of CT Cases
71 of CT Cases
87 of Pop. Tested
13 of Pop. Tested
34

• Patients screened for CT
• Age 26-44
• N 2,287 nCT 59
• No STD contact
• No cervicitis or PID
• No new STD dx (except GC)
• 2.6 CT

Patients age 26-30 screened for CT N 1,162
nCT 41 3.5 CT
Patients age 31-44 screened for CT N 1,126
nCT 18 1.6 CT
35
The Over 25 EvaluationSummary of
Univariate/Multivariate Findings Women age Over
25 (26-44)

• Risk factors predictive for CT infection
  (statistically significantly)
• Age lt 30 (26-30)
• Partners possible other partners (no time frame)
• New partner (2 mos)
• Vaginal DC on exam unknown etiology (not
  cervicitis, trich, BV, or yeast)
• More than 1 partner (12m) (p-value 0.13)
• Complaints of pain or bleeding with sex, pelvic
  pain, or spotting (p-value 0.18)
• Asian race (p-value 0.18)

Independently associated with CT in
multivariate analysis (p-value lt0.05)
36
The Over 25 EvaluationSummary of
Univariate/Multivariate Findings Women age Over
30 (31-44)

• Risk factors predictive for CT infection
• Age lt 35 (31-35)
• (p-value 0.12)
• Partners possible other partners (no timeframe)
• (p-value 0.26)

37
Summary of Cross-Study Statistical Findings
Risk factors predictive of CT infection
Over 25 EvalAge 26-44
Over 20 StudyAge 26-30
Predictive Risk Factor
38
The Over 20 Study Screening AnalysisResults
Performance of Selective Screening AlgorithmsAge
gt 25 (26-30)
Actual number of cases and screened population
varies by algorithm due to missing values
Approximate replication
39
The Over 25 Evaluation Weighted Screening
AnalysisResults Performance of Selective
Screening AlgorithmsAge gt 25 (26-44)
Actual number of cases and screened population
varies by algorithm due to missing values
Abstracted random sample weighted-up to full
tested population by site Approximate
replication
40
Implications for Screening Recommendations for
Non-Pregnant Women gt Age 25

• Partner(s) possibly having had other concurrent
  partners (during past 12 mos) was the strongest
  predictor of CT in these research projects
• Other fairly consistent behavioral predictors of
  CT included
• gt 1 partners in past 12 mos
• New partner in past 2-3 mos
• Younger age, specifically age 26-30, was a strong
  demographic predictor of CT
• Possible clinical predictors include BV and
  Vaginal DC on exam with no known etiology

41
Proposed CT Testing Screening Recommendations
for Non-Pregnant Women gt Age 25

• Testing based on clear clinical indications
• Current contact (exposure) to any STD
• Clinical signs of cervicitis or PID
• Newly confirmed or presumptively treated other
  STD dx
• ? Additional discussion about other clinical
  considerations for clinician discretion
• Vaginal DC on exam with unknown etiology
  (cervicitis?)
• BV dx in some populations
• Retesting Encourage CT clients RTC in 3 mos
• Targeted Screening based on risk factors
• Partner possible other partners during past 12
  mos!!!
• More than 1 partner during past 12 mos (more than
  2 partners)
• New partner during past 2-3 mos
• Additional discussion higher CT risk often
  associated with younger age emphasis on
  prioritizing age 26-30

42
Acknowledgements
Thank you!

• CADHS-STD
• Joan Chow, Heidi Bauer, Erika Samoff, Gail Bolan
• CFHC
• Melanie Deal, Christy Ngo, Jackie Provost,
  Rebecca Braun, Lani Pasion
• Lab Partners
• Quest Diagnostics, Medical Group Pathology
  Laboratory,
• UCSF Chlamydia Research Laboratory (Julius
  Schachter),
• Planned Parenthood Mar Monte Laboratory (Jill A.
  MacAfee)
• And all The Over 20 Over 25 Participating
  Clinic Sites
• For further information, please contact
• Holly Howard at hhoward_at_dhs.ca.gov