Validity of self-reported history of Chlamydia trachomatis infection

A potential role for chlamydial infection in rheumatoid arthritis development

OBJECTIVES

To assess the relationship between self-reported and serologic evidence of prior chlamydial infection, rheumatoid arthritis (RA)-related autoantibodies and risk of RA-development.

METHODS

This is a nested study within a prospective Swiss-based cohort including all first-degree relatives of RA patients (RA-FDR) who answered a question on past chlamydial infections. Primary outcome was systemic autoimmunity associated with RA (RA-autoimmunity) defined as positivity for anti-citrullinated peptide antibodies (ACPA) and/or rheumatoid factor (RF). Secondary outcomes were high levels of RA-autoimmunity, RA-associated symptoms and RA-autoimmunity, and subsequent seropositive RA diagnosis. We conducted a nested case-control analysis by measuring the serological status against Chlamydia trachomatis' major outer membrane protein. We replicated our analysis in an independent United States-based RA-FDR cohort.

RESULTS

Among 1231 RA-FDRs, 168 (13.6%) developed RA-autoimmunity. Prevalence of self-reported chlamydial infection was significantly higher in individuals with RA-autoimmunity compared with controls (17.9% vs 9.8%, OR = 2.00, 95%CI: 1.27-3.09, p < 0.01). This association remained significant after adjustments (OR = 1.91, 95%CI: 1.20-2.95). Stronger effect sizes were observed in later stages of RA development. There was a similar trend between a positive C. trachomatis serology and high levels of RA-autoimmunity (OR = 3.05, 95% CI: 1.10-8.46, p= 0.032). In the replication cohort, there were significant associations between chlamydial infection and RF positivity and incident RA, but not anti-CCP positivity.

CONCLUSIONS

Self-reported chlamydial infections are associated with elevated RA-autoimmunity in at risk individuals. The differing association of chlamydial infections and ACPA/RF between cohorts will need to be explored in future studies but is consistent with a role of mucosal origin of RA-related autoimmunity.

Reliability of prisoners' survey responses: comparison of self-reported health and biomedical data from an australian prisoner cohort

OBJECTIVE

Prisoner health surveys primarily rely on self-report data. However, it is unclear whether prisoners are reliable health survey respondents. This paper aimed to determine the level of agreement between self-report and biomedical tests for a number of chronic health conditions.

METHOD

This study was a secondary analysis of existing data from three waves (1996, 2001, 2009) of the New South Wales (NSW) Inmate Health Survey. The health surveys were cross-sectional in nature and included a stratified random sample of men (n=2,114) from all NSW prisons. Self-reported histories of hepatitis, sexually transmissible infections, and diabetes were compared to objective biomedical measures of these conditions.

RESULTS

Overall, the sensitivity (i.e., the respondents who self-reported having the condition also had markers indicative of the condition using biomedical tests) was high for hepatitis C (96%) and hepatitis B (83%), but low for all other assessed conditions (ranging from 9.1% for syphilis using RPR to 64% for diabetes). However, Kappa scores indicated substantial agreement only for hepatitis C. That is, there were false positives and false negatives which occurred outside of chance leading to poor agreement for all other assessed conditions.

CONCLUSIONS

Prisoners may have been exposed to serious health conditions while failing to report a history of infection. It may be possible that prisoners do not get tested given the asymptomatic presentation of some conditions, were unaware of their health status, have limited health-service usage preventing the opportunity for detection, or are subject to forgetting or misunderstanding prior test results. These findings demonstrate the importance of the custodial environment in screening for health conditions and referral for treatment should this be needed. Testing on entry, periodically during incarceration, and prior to release is recommended.

Intrauterine Devices and Sexually Transmitted Infection among Older Adolescents and Young Adults in a Cluster Randomized Trial

STUDY OBJECTIVE

Provider misconceptions regarding intrauterine device (IUD) safety for adolescents and young women can unnecessarily limit contraceptive options offered; we sought to evaluate rates of Neisseria gonorrhoeae or Chlamydia trachomatis (GC/CT) diagnoses among young women who adopted IUDs.

DESIGN

Secondary analysis of a cluster-randomized provider educational trial.

SETTING

Forty US-based reproductive health centers.

PARTICIPANTS

We followed 1350 participants for 12 months aged 18-25 years who sought contraceptive care.

INTERVENTIONS

The parent study assessed the effect of provider training on evidence-based contraceptive counseling.

MAIN OUTCOME MEASURES

We assessed incidence of GC/CT diagnoses according to IUD use and sexually transmitted infection risk factors using Cox regression modeling and generalized estimating equations.

RESULTS

Two hundred four participants had GC/CT history at baseline; 103 received a new GC/CT diagnosis over the 12-month follow-up period. IUDs were initiated by 194 participants. Incidence of GC/CT diagnosis was 10.0 per 100 person-years during IUD use vs 8.0 otherwise. In adjusted models, IUD use (adjusted hazard ratio [aHR], 1.31; 95% confidence interval [CI], 0.71-2.40), adolescent age (aHR, 1.28; 95% CI, 0.72-2.27), history of GC/CT (aHR, 1.23; 95% CI, 0.75-2.00), and intervention status (aHR, 1.12; 95% CI, 0.74-1.71) were not associated with GC/CT diagnosis; however, new GC/CT diagnosis rates were significantly higher among individuals who reported multiple partners at baseline (aHR, 2.0; 95% CI, 1.34-2.98).

CONCLUSION

In this young study population with GC/CT history, this use of IUDs was safe and did not lead to increased GC/CT diagnoses. However, results highlighted the importance of dual sexually transmitted infection and pregnancy protection for participants with multiple partners.

High Pgp3 Chlamydia trachomatis seropositivity, pelvic inflammatory disease and infertility among women, National Health and Nutrition Examination Survey, United States, 2013-2016

BACKGROUND

Chlamydia trachomatis causes pelvic inflammatory disease (PID) and tubal infertility. Pgp3 antibody (Pgp3Ab) detects prior chlamydial infections. We evaluated for an association of high chlamydial seropositivity with sequelae using a Pgp3Ab multiplex bead array (Pgp3AbMBA).

METHODS

We performed chlamydia Pgp3AbMBA on sera from women 18-39 years old participating in the 2013-2016 National Health and Nutrition Examination Survey (NHANES) with urine chlamydia nucleic acid amplification test results. High chlamydial seropositivity was defined as a median fluorescence intensity (MFI ≥ 50,000; low-positive was MFI > 551-<50,000. Weighted US population high-positive, low-positive, and negative Pgp3Ab chlamydia seroprevalence and 95% confidence intervals (95% CI) were compared for women with chlamydial infection, self-reported PID, and infertility.

RESULTS

Of 2,339 women aged 18-39 years, 1,725 (73.7%) had sera and 1,425 were sexually experienced. Overall, 104 women had high positive Pgp3Ab (5.4% [95% CI 4.0-7.0] of US women); 407 had low positive Pgp3Ab (25.1% [95% CI 21.5-29.0]), and 914 had negative Pgp3Ab (69.5% [95% CI 65.5-73.4]).Among women with high Pgp3Ab, infertility prevalence was 2.0 (95% CI 1.1-3.7) times higher than among Pgp3Ab-negative women (19.6% [95% CI 10.5-31.7] versus 9.9% [95% CI 7.7-12.4]). For women with low Pgp3Ab, PID prevalence was 7.9% (95% CI 4.6-12.6) compared to 2.3% (95% CI 1.4-3.6) in negative Pgp3Ab.

CONCLUSIONS

High chlamydial Pgp3Ab seropositivity was associated with infertility although small sample size limited evaluation of an association of high seropositivity with PID. In infertile women, Pgp3Ab may be a marker of prior chlamydial infection.

Methods to mitigate infection spread from aerosol-generating dental procedures

Infection control measures play a critical role in preventing the spread of disease in healthcare settings. Concerns that SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2), the virus that causes Coronavirus Disease 2019, may be transmitted through droplets and aerosols from both symptomatic and asymptomatic individuals has turned the spotlight on healthcare interventions that involve aerosol generation in the oral cavity, such as many dental and periodontal procedures. This commentary seeks to familiarize the dental practitioner with various infection control methods that may be implemented to mitigate spread of infection in dental settings through aerosol-generating dental procedures.

Recall accuracy of notifications about incidental findings from an MRI examination: results from a population-based study

BACKGROUND

Self-reports of medical findings are indispensable in clinical practice and research but subject to recall bias. We analysed the recall accuracy of notifications about incidental findings (IFs) from a whole-body MRI examination and assessed determinants of recall error.

METHODS

Data from 3746 participants of a postal follow-up survey conducted on average 2.47 years after examination in the population-based Study of Health in Pomerania were analysed. Among those, 2185 (58.3%) underwent whole-body MRI at baseline, and findings of potential clinical relevance were disclosed in standardised postal letters. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were calculated to determine the accuracy of self-reports. Poisson regression analysis was conducted to analyse predictors for false-positive and false-negative recall.

RESULTS

An IF was disclosed to 622 (28.5%) individuals; 81.5% had tumour relevance. The overall sensitivity and PPV of participants' self-reports were 80% and 60%, respectively. PPvs were higher among women, better educated and married participants and among those with good verbal memory. Among MRI participants, lower educational level was associated with a higher risk of false-positive recall (risk ratio (RR) 1.44, 95% CI 1.01 to 2.03), while increasing age was associated with a higher risk of false-negative recall (RR 1.64, 95% CI 1.33 to 2.01).

CONCLUSIONS

Most participants correctly recalled disclosed IFs. However, the probability of an event in case of a positive recall is barely above 50%. Therefore, relying on subjects' recall of disclosed IFs will lead to a relevant proportion of errors. Clinicians and researchers should be aware of this problem and of participants' characteristics which may moderate the probability of correct decisions based on recalled findings.

Self-Reported History of Chlamydia or Gonorrhea Testing Among Heterosexual Women at High Risk of HIV Infection, National HIV Behavioral Surveillance, 2013

BACKGROUND

The US Preventive Services Task Force recommends annual chlamydia and gonorrhea screening for sexually active women <25 and ≥25 years old with associated risk factors. We sought to determine self-reported chlamydia and gonorrhea testing and diagnosis rates in the past 12 months in a community-based sample of heterosexual women at high risk of HIV infection.

METHODS

We used National HIV Behavioral Surveillance data from 2013 when surveillance was conducted in heterosexual adults with low social economic status. Our analysis was restricted to 18- to 44-year-old women who answered questions regarding chlamydia/gonorrhea testing and diagnosis in the previous 12 months. We calculated the percentage reporting testing and diagnosis. Poisson regressions with generalized estimating equations clustered on recruitment chain were used to assess factors associated with testing and diagnosis.

RESULTS

Among 18- to 24-year-old women (n = 1017), 61.0% self-reported chlamydia testing and 57.6% gonorrhea testing in the past 12 months. Among 25- to 44-year-old women (n = 2322), 49.0% and 47.0% reported chlamydia and gonorrhea testing, respectively. Among the subset of 25- to 44-year-old women who met screening criteria, 51.2% reported chlamydia testing. Having seen a medical provider and HIV testing (past 12 months) were associated with chlamydia/gonorrhea testing in both age groups. Self-reported chlamydia (18-24 years, 21.4%; 25-44 years, 12.2%) and gonorrhea diagnoses (18-24 years, 8.4%; 25-44 years, 6.6%) were common.

CONCLUSIONS

A substantial number of eligible women may not have been screened for chlamydia/gonorrhea. Renewed efforts to facilitate screening may prevent sequelae and support disease control activities.

Association between pubic hair grooming and prevalent sexually transmitted infection among female university students

Recent findings have suggested an association between pubic hair grooming and self-reported history of sexually transmitted infection (STI), specifically gonococcal infection (GC), chlamydial infection (CT), or human immunodeficiency virus (HIV). We evaluated the association between self-reported extreme grooming and laboratory-confirmed prevalence of GC/CT. Between April 2017 and April 2018, we enrolled English-speaking, adult, female students at a large, Midwestern university who presented on-campus for STI testing. Participants completed a questionnaire on demographics and sexual and grooming behaviors, which was linked to their GC/CT test results based on nucleic acid amplification testing. We defined extreme grooming as removal of all pubic hair either at least weekly in the past 12 months or ≥6 times in the past 30 days. We used two separate logistic regression models to determine whether odds of GC/CT varied by extreme groomer status for either time interval. In the study sample of 214 women, prevalence of GC/CT was 9.8%. Nearly all participants (98.1%) reported ever grooming; 53.6% were extreme groomers in the past year and 18% in the past month. Extreme grooming was not associated with prevalent GC/CT in the past year (odds ratio [OR] = 0.8; 95% confidence interval [CI]: 0.3-1.9; adjusted OR = 0.7; 95% CI: 0.3-2.0) or in the past month (OR = 0.5; 95% CI: 0.1-2.0; aOR = 0.4; 95% CI: 0.1-1.9). Pubic hair grooming was common among female university students attending for STI testing. Findings do not support pubic hair grooming as an STI risk factor in this population.

Advancing the public health applications of Chlamydia trachomatis serology

Genital Chlamydia trachomatis infection is the most commonly diagnosed sexually transmitted infection. Trachoma is caused by ocular infection with C trachomatis and is the leading infectious cause of blindness worldwide. New serological assays for C trachomatis could facilitate improved understanding of C trachomatis epidemiology and prevention. C trachomatis serology offers a means of investigating the incidence of chlamydia infection and might be developed as a biomarker of scarring sequelae, such as pelvic inflammatory disease. Therefore, serological assays have potential as epidemiological tools to quantify unmet need, inform service planning, evaluate interventions including screening and treatment, and to assess new vaccine candidates. However, questions about the performance characteristics and interpretation of C trachomatis serological assays remain, which must be addressed to advance development within this field. In this Personal View, we explore the available information about C trachomatis serology and propose several priority actions. These actions involve development of target product profiles to guide assay selection and assessment across multiple applications and populations, establishment of a serum bank to facilitate assay development and evaluation, and development of technical and statistical methods for assay evaluation and analysis of serological findings. The field of C trachomatis serology will benefit from collaboration across the public health community to align technological developments with their potential applications.

Chlamydia trachomatis Seroprevalence and Ultrasound-Diagnosed Uterine Fibroids in a Large Population of Young African-American Women

Reproductive tract infections have long been hypothesized to increase the risk of uterine fibroids. Few studies have been conducted, even for the common infection genital Chlamydia trachomatis (gCT), and only with self-reported gCT data. Our investigation used micro-immunofluorescence serology for gCT to characterize past exposure. We used cross-sectional enrollment data from a prospective fibroid study carried out in the Detroit, Michigan, area; ultrasound examinations systematically screened for fibroids. Participants were African-American women aged 23-34 years (recruited in 2010-2012). Age- and multivariable-adjusted logistic regression models were used to estimate odds ratios. A total of 1,587 women (94% of participants) had unequivocal gCT serology results; 22% had fibroids. Those who were seropositive for gCT were less likely to have fibroids (age-adjusted odds ratio = 0.68, 95% confidence interval: 0.54, 0.87; multivariable-adjusted odds ratio = 0.80, 95% confidence interval: 0.62, 1.03). Inverse associations were similar across categories of fibroid size, number, and total volume. Participant groups likely to have had multiple or severe infections (multiple serovar groups, more sex partners, clinically diagnosed chlamydia) all showed statistically significantly reduced odds of fibroids. A protective association of gCT with fibroids was unexpected but plausible. gCT infection might increase immune surveillance and eliminate early lesions. Further investigation on the relationship between fibroid development and reproductive tract infections is needed.

Misreporting of contraceptive hormone use in clinical research participants

Objective

Researchers traditionally rely on participant self-report for contraceptive use. We hypothesized that self-reported contraceptive use by clinical research participants may disagree with objectively measured hormonal status.

Study design

We enrolled women in Harare, Zimbabwe, aged 18–34, who by self-report had not used hormonal or intrauterine contraception for >30 days, or depot medroxyprogesterone acetate for >10 months, into a study designed to assess biologic changes with contraceptive initiation and use. Blood samples obtained at enrollment and each follow-up visit (N=1630 from 447 participants) were evaluated by mass spectrometry for exogenous hormones. We individually interviewed a subset of participants (n=20) with discrepant self-reported and measured serum hormones to better understand nondisclosure of contraceptive use.

Results

Discrepant with self-reported nonuse of hormonal contraception, synthetic progestogens were detectable in 120/447 (27%, 95% confidence interval 23%–31%) enrolled women. Measured exogenous hormones consistent with use of contraceptive pills (n=102), injectables (n=20) and implants (n=3) were detected at enrollment, with 7 women likely using >1 contraceptive. In-depth interviews revealed that participants understood the requirement to be hormone free at enrollment (100%). Most (85%) cited partner noncooperation with condoms/withdrawal and/or pregnancy concerns as major reasons for nondisclosed contraceptive use. All interviewed women (100%) cited access to health care as a primary motivation for study participation. Of participants who accurately reported nonuse of hormonal contraception at enrollment, 41/327 (12.5%) had objective evidence of nonstudy progestin use at follow-up that disagreed with self-reported nonuse.

Conclusions

Women joining contraceptive research studies may misrepresent their use of nonstudy contraceptive hormones at baseline and follow-up. Objective measures of hormone use are needed to ensure that study population exposures are accurately categorized.

Implications statement

Among Zimbabwean women participating in a contraceptive research study, 27% had objective evidence of use of nonstudy contraceptives at enrollment that disagreed with self-report. Studies that rely on self-report to identify contraceptive hormone exposure could suffer from significant misclassification.