A pilot registry of unexplained fatiguing illnesses and chronic fatigue syndrome

Background

Chronic fatigue syndrome (CFS) has no diagnostic clinical signs or biomarkers, so diagnosis requires ruling out conditions with similar signs and symptoms. We conducted a pilot registry of unexplained fatiguing illnesses and CFS to determine the feasibility of establishing and operating a registry and implementing an education outreach initiative. The pilot registry was conducted in Bibb County, Georgia. Patient referrals were obtained from healthcare providers who were identified by using various education outreach initiatives. These referrals were later supplemented with self-referrals by members of a local CFS support group. All patients meeting referral criteria were invited to participate in a screening interview to determine eligibility. If patients met registry criteria, they were invited to a one-day clinic for physical and laboratory evaluations. We classified patients based on the 1994 case definition.

Results

We registered 827 healthcare providers. Forty-two providers referred 88 patients, and 58 patients (66%) completed clinical evaluation. Of the 188 CFS support group members, 53 were self-referred and 46 (87%) completed the clinical evaluation. Of the 104 participants completing evaluation, 36% (n = 37) met the criteria for CFS, 17% (n = 18) had insufficient fatigue or symptoms (ISF), and 47% (n = 49) were found to have exclusionary medical or psychiatric illnesses. Classification varied significantly by type of referral but not by previous history of CFS diagnosis. Healthcare providers referred more patients who were classified as CFS as compared to support group referrals in which more exclusionary conditions were identified. Family practice and internal medicine specialties made the most referrals and had the highest number of CFS cases. We conducted three CME events, held three “Meet and Greet” sessions, visited four large clinical health practices and health departments, mailed five registry newsletters, and conducted in-person office visits as part of education outreach, which contributed to patient referrals.

Conclusions

Referrals from healthcare providers and self-referrals from the patient support group were important to registry enrollment. The number of potentially treatable conditions that were identified highlights the need for continued medical management in this population, as well as the limitations of registries formed without clinical examination. Education initiatives were successful in part because of partnerships with local organizations.

Reduction in human papillomavirus (HPV) prevalence among young women following HPV vaccine introduction in the United States, National Health and Nutrition Examination Surveys, 2003-2010

BACKGROUND

Human papillomavirus (HPV) vaccination was introduced into the routine immunization schedule in the United States in late 2006 for females aged 11 or 12 years, with catch-up vaccination recommended for those aged 13-26 years. In 2010, 3-dose vaccine coverage was only 32% among 13-17 year-olds. Reduction in the prevalence of HPV types targeted by the quadrivalent vaccine (HPV-6, -11, -16, and -18) will be one of the first measures of vaccine impact.

METHODS

We analyzed HPV prevalence data from the vaccine era (2007-2010) and the prevaccine era (2003-2006) that were collected during National Health and Nutrition Examination Surveys. HPV prevalence was determined by the Linear Array HPV Assay in cervicovaginal swab samples from females aged 14-59 years; 4150 provided samples in 2003-2006, and 4253 provided samples in 2007-2010.

RESULTS

Among females aged 14-19 years, the vaccine-type HPV prevalence (HPV-6, -11, -16, or -18) decreased from 11.5% (95% confidence interval [CI], 9.2-14.4) in 2003-2006 to 5.1% (95% CI, 3.8-6.6) in 2007-2010, a decline of 56% (95% CI, 38-69). Among other age groups, the prevalence did not differ significantly between the 2 time periods (P > .05). The vaccine effectiveness of at least 1 dose was 82% (95% CI, 53-93).

CONCLUSIONS

Within 4 years of vaccine introduction, the vaccine-type HPV prevalence decreased among females aged 14-19 years despite low vaccine uptake. The estimated vaccine effectiveness was high.

Multiscale analysis of heart rate variability in non-stationary environments

Heart rate variability (HRV) is highly non-stationary, even if no perturbing influences can be identified during the recording of the data. The non-stationarity becomes more profound when HRV data are measured in intrinsically non-stationary environments, such as social stress. In general, HRV data measured in such situations are more difficult to analyze than those measured in constant environments. In this paper, we analyze HRV data measured during a social stress test using two multiscale approaches, the adaptive fractal analysis (AFA) and scale-dependent Lyapunov exponent (SDLE), for the purpose of uncovering differences in HRV between chronic fatigue syndrome (CFS) patients and their matched-controls. CFS is a debilitating, heterogeneous illness with no known biomarker. HRV has shown some promise recently as a non-invasive measure of subtle physiological disturbances and trauma that are otherwise difficult to assess. If the HRV in persons with CFS are significantly different from their healthy controls, then certain cardiac irregularities may constitute good candidate biomarkers for CFS. Our multiscale analyses show that there are notable differences in HRV between CFS and their matched controls before a social stress test, but these differences seem to diminish during the test. These analyses illustrate that the two employed multiscale approaches could be useful for the analysis of HRV measured in various environments, both stationary and non-stationary.

Modeling the impact of quadrivalent HPV vaccination on the incidence of Pap test abnormalities in the United States

BACKGROUND

We present data on Pap test results and HPV prevalence from the HPV Sentinel Surveillance project, a multiyear surveillance project enrolling women from a diverse set of 26 clinics throughout the US from 2003 to 2005. We use mathematical modeling to illustrate the potential timing and magnitude of decreases in Pap test abnormalities in sexually transmitted disease (STD), family planning, and primary care clinics in the US as a result of HPV vaccination.

METHODS

The probability of an abnormal Pap result was based on three factors: (1) infection with HPV 16/18, or both; (2) infection with high-risk HPV types other than HPV 16/18; and (3) infection with HPV 6/11, or both. We estimated the relative reduction in the probability of an abnormal Pap result over the first 25 years of a female-only, quadrivalent HPV vaccination program, compared to a scenario of no HPV vaccination in which the probability of abnormal Pap results was assumed constant.

RESULTS

The probability of an abnormal Pap result ranged from 7.0% for the lowest risk group (those without any high-risk HPV types and without HPV 6/11) to 45.2% for the highest risk group (those with HPV 16/18 and at least one other high-risk HPV type). Estimated reductions in abnormal Pap results among women in the 21- to 29-year age group were 0.8%, 10.2%, and 11.3% in years 5, 15, and 25 of the vaccine program respectively, in the lower vaccine coverage scenario, and 7.4%, 21.4%, and 22.2%, respectively, in the higher coverage scenario.

CONCLUSIONS

Our results suggest that HPV vaccination will have a discernable impact on the probability of Pap abnormalities, but the timing and magnitude of the reduction will depend substantially on vaccine coverage and the degree of cross-protection against high risk HPV types other than HPV 16/18.

Can clinical tests help monitor human papillomavirus vaccine impact?

As immunization programs for human papillomavirus (HPV) are implemented more widely around the world, interest is increasing in measuring their impact. One early measurable impact of HPV vaccine is on the prevalence of specific HPV types in a population. In low-resource settings, a potentially attractive strategy would be to monitor HPV prevalence using clinical cervical cancer screening test results to triage specimens for HPV typing. We assessed this approach in a nationally representative population of U.S. females aged 14-59 years. Using self-collected cervico-vaginal swab specimens from 4,150 women participating in the National Health and Nutrition Examination Survey during 2003-2006, we evaluated type-specific HPV prevalence detected by the Roche linear array (LA) research test on all specimens, compared with type-specific HPV prevalence detected by LA conducted only on specimens positive by the digene hybrid capture 2 (HC-2) clinical test. We calculated weighted prevalence estimates and their 95% confidence intervals (CIs), and examined relative type-specific HPV prevalence according to the two testing approaches. The population prevalence of oncogenic HPV vaccine types 16/18 was 6.2% (CI:5.4-7.1) by LA if all specimens were tested, and 2.4% (CI:1.9-3.0) if restricted to positive HC-2. Relative prevalence of individual HPV types was similar for both approaches. Compared with typing all specimens, a triage approach would require testing fewer specimens, but a greater reduction in HPV prevalence or a larger group of specimens would be needed to detect vaccine impact. Further investigation is warranted to inform type-specific HPV monitoring approaches around the world.

Acute psychosocial stress-mediated changes in the expression and methylation of perforin in chronic fatigue syndrome

Perforin (PRF1) is essential for immune surveillance and studies report decreased perforin in chronic fatigue syndrome (CFS), an illness potentially associated with stress and/or infection. We hypothesize that stress can influence regulation of PRF1 expression, and that this regulation will differ between CFS and non-fatigued (NF) controls. We used the Trier Social Stress Test (TSST) as a standardized acute psychosocial stress, and evaluated its effect on PRF1 expression and methylation in CFS (n = 34) compared with NF (n = 47) participants. During the TSST, natural killer (NK) cells increased significantly in both CFS (P = <0.0001) and NF subjects (P = <0.0001). Unlike previous reports, there was no significant difference in PRF1 expression at baseline or during TSST between CFS and NF. However, whole blood PRF1 expression increased 1.6 fold during the TSST in both CFS (P = 0.0003) and NF (P = <0.0001). Further, the peak response immediately following the TSST was lower in CFS compared with NF (P = 0.04). In addition, at 1.5 hours post TSST, PRF1 expression was elevated in CFS compared with NF (whole blood, P = 0.06; PBMC, P = 0.02). Methylation of seven CpG sites in the methylation sensitive region of the PRF1 promoter ranged from 38%–79% with no significant differences between CFS and NF. Although, the average baseline methylation of all seven CpG sites did not differ between CFS and NF groups, it showed a significant negative correlation with PRF1 expression at all TSST time points in both CFS (r = −0.56, P = <0.0001) and NF (r = −0.38, P = <0.0001). Among participants with high average methylation (≥65%), PRF1 expression was significantly lower in CFS than NF subjects immediately following TSST. These findings suggest methylation could be an important epigenetic determinant of inter-individual differences in PRF1 expression and that the differences in PRF1 expression and methylation between CFS and NF in the acute stress response require further investigation.

Prevalence of HPV types in cervical specimens from an integrated healthcare delivery system: baseline assessment to measure HPV vaccine impact

PURPOSE

Two human papillomavirus (HPV) vaccines are available to prevent cervical cancer. One early measure of HPV vaccine impact would be a reduction in vaccine-related HPV types (HPV 6, 11, 16, or 18, or HPV 16, 18) in cervical samples from young women. We aimed to assess feasibility of specimen collection and baseline HPV prevalence in an integrated healthcare delivery system.

METHODS

Residual cervical specimens collected during routine cervical cancer screening (2006-2008) were retained consecutively from eligible females aged 11-29 years, stratified by age group. Specimens were evaluated for 37 HPV genotypes using the Roche Linear Array assay.

RESULTS

Of 10,124 specimens submitted, 10,103 (99 %) were adequate for HPV testing. Prevalence of HPV 6, 11, 16, or 18 genotype was 11.4 % overall and was the highest in the youngest age group (18.1 % in the 11-19-year-olds, 12.5 % in the 20-24-year-olds, and 7.0 % in the 25-29-year-olds).

CONCLUSIONS

HPV types 6, 11, 16, or 18 prevalence could be measured over time to assess early HPV vaccine impact using residual specimens from an integrated healthcare delivery system, particularly if sampling focused on young women.

Sensitive and specific peak detection for SELDI-TOF mass spectrometry using a wavelet/neural-network based approach

SELDI-TOF mass spectrometer's compact size and automated, high throughput design have been attractive to clinical researchers, and the platform has seen steady-use in biomarker studies. Despite new algorithms and preprocessing pipelines that have been developed to address reproducibility issues, visual inspection of the results of SELDI spectra preprocessing by the best algorithms still shows miscalled peaks and systematic sources of error. This suggests that there continues to be problems with SELDI preprocessing. In this work, we study the preprocessing of SELDI in detail and introduce improvements. While many algorithms, including the vendor supplied software, can identify peak clusters of specific mass (or m/z) in groups of spectra with high specificity and low false discover rate (FDR), the algorithms tend to underperform estimating the exact prevalence and intensity of peaks in those clusters. Thus group differences that at first appear very strong are shown, after careful and laborious hand inspection of the spectra, to be less than significant. Here we introduce a wavelet/neural network based algorithm which mimics what a team of expert, human users would call for peaks in each of several hundred spectra in a typical SELDI clinical study. The wavelet denoising part of the algorithm optimally smoothes the signal in each spectrum according to an improved suite of signal processing algorithms previously reported (the LibSELDI toolbox under development). The neural network part of the algorithm combines those results with the raw signal and a training dataset of expertly called peaks, to call peaks in a test set of spectra with approximately 95% accuracy. The new method was applied to data collected from a study of cervical mucus for the early detection of cervical cancer in HPV infected women. The method shows promise in addressing the ongoing SELDI reproducibility issues.

Human papillomavirus genotypes in high-grade cervical lesions in the United States

BACKGROUND

Two vaccines protect against human papillomaviruses (HPV) 16 and 18, which cause 70% of cervical cancer and 50% of cervical intraepithelial neoplasia 2/3 and adenocarcinoma in situ (CIN2+). Monitoring HPV types in CIN2+ may be used to assess HPV vaccine impact.

METHODS

As part of a multisite vaccine impact monitoring project (HPV-IMPACT), biopsy specimens used to diagnose CIN2+ were obtained for HPV DNA typing for women aged 18-39 years.

RESULTS

Among 4,121 CIN2+ cases reported during 2008-2009 in 18- to 39-year-old women 3058 (74.2%) were tested; 96% were HPV DNA positive. HPV 16 was most common (49.1%), followed by HPV 31 (10.4%) and HPV 52 (9.7%). HPV 18 prevalence was 5.5% overall. Proportion of CIN2+ cases associated with HPV 16/18 was highest (56.3%) in 25- to 29-year-old women. HPV 16/18-associated lesions were less common in non-Hispanic blacks (41.9%) and Hispanics (46.3%) compared with non-Hispanic whites (59.1%) (P < .0001); the difference remained significant when adjusted for covariates. Compared to non-Hispanic whites, HPV 35 and 58 were significantly more common in non-Hispanic blacks (14.5% vs 4.2%; 12.3% vs 3.4%) and HPV 45 was higher in Hispanics (3.7% vs 1.5%).

CONCLUSIONS

Age and racial/ethnic differences in HPV type distribution may have implications for vaccine impact and should be considered in monitoring trends.

Continuous-flow Ferrohydrodynamic Sorting of Particles and Cells in Microfluidic Devices

A new sorting scheme based on ferrofluid hydrodynamics (ferrohydrodynamics) was used to separate mixtures of particles and live cells simultaneously. Two species of cells, including Escherichia coli and Saccharomyces cerevisiae, as well as fluorescent polystyrene microparticles were studied for their sorting throughput and efficiency. Ferrofluids are stable magnetic nanoparticles suspensions. Under external magnetic fields, magnetic buoyancy forces exerted on particles and cells lead to size-dependent deflections from their laminar flow paths and result in spatial separation. We report the design, modeling, fabrication and characterization of the sorting device. This scheme is simple, low-cost and label-free compared to other existing techniques.

Prevalence of human papillomavirus types in invasive vulvar cancers and vulvar intraepithelial neoplasia 3 in the United States before vaccine introduction

OBJECTIVE

The study aimed to determine the baseline prevalence of human papillomavirus (HPV) types in invasive vulvar cancer (IVC) and vulvar intraepithelial neoplasia 3 (VIN 3) cases using data from 7 US cancer registries.

MATERIALS AND METHODS

Registries identified eligible cases diagnosed in 1994 to 2005 and requested pathology laboratories to prepare 1 representative block for HPV testing on those selected. Hematoxylin-eosin-stained sections preceding and following those used for extraction were reviewed to confirm representation. Human papillomavirus was detected using L1 consensus polymerase chain reaction (PCR) with PGMY9/11 primers and type-specific hybridization, with retesting of samples with negative and inadequate results with SPF10 primers. For IVC, the confirmatory hematoxylin-eosin slides were re-evaluated to determine histological type. Descriptive analyses were performed to examine distributions of HPV by histology and other factors.

RESULTS

Human papillomavirus was detected in 121/176 (68.8%) cases of IVC and 66/68 (97.1%) cases of VIN 3 (p < .0001). Patients with IVC and VIN 3 differed by median age (70 vs 55 y, p = .003). Human papillomavirus 16 was present in 48.6% of IVC cases and 80.9% of VIN 3 cases; other high-risk HPV was present in 19.2% of IVC cases and 13.2% of VIN 3 cases. Prevalence of HPV differed by squamous cell carcinoma histological subtype (p < .0001) as follows: keratinizing, 49.1% (n = 55); nonkeratinizing, 85.7% (n = 14), basaloid, 92.3% (n = 14), warty 78.2% (n = 55), and mixed warty/basaloid, 100% (n = 7).

CONCLUSIONS

Nearly all cases of VIN 3 and two thirds of IVC cases were positive for high-risk HPV. Prevalence of HPV ranged from 49.1% to 100% across squamous cell carcinoma histological subtypes. Given the high prevalence of HPV in IVC and VIN 3 cases, prophylactic vaccines have the potential to decrease the incidence of vulvar neoplasia.

Patterns of cellular and HPV 16 methylation as biomarkers for cervical neoplasia

Aberrant promoter methylation of biologically relevant genes in cervical cancer and uneven CpG distribution within the human papillomavirus 16 (HPV 16) enhancer region have been reported. Cervical samples and questionnaires from 151 women screened for cervical cancer in Appalachian Ohio were analyzed. Methylation was measured by bisulfite sequencing in candidate gene sites in ESR1, DCC, p16, and LINE1 elements. Among 89 HPV 16-positive women, CpG sites in the E6 promoter and enhancer regions and the L1 region of the HPV 16 genome were measured. Methylation levels were compared by cervical cytology and HPV 16 status. HPV methylation was low regardless of cytology status, however E6 methylation was significantly higher in women with normal cytology. ESR1 and DCC methylation were significantly higher in HPV 16-positive women. Increased methylation at sites in the E6 promoter region was associated with lower odds of abnormal cytology. Increased methylation in candidate genes was associated with higher odds of abnormal cytology, particularly DCC region 2.4, DCC region 2.6, ESR1 region 3.2, and LINE1 site 1.2. HPV 16 genome CpG methylation was low except for the L1 region. In general, lower HPV 16 methylation and higher candidate gene methylation levels were associated with higher odds of abnormal cytology.

HPV genotypes in high grade cervical lesions and invasive cervical carcinoma as detected by two commercial DNA assays, North Carolina, 2001-2006

BACKGROUND

HPV typing using formalin fixed paraffin embedded (FFPE) cervical tissue is used to evaluate HPV vaccine impact, but DNA yield and quality in FFPE specimens can negatively affect test results. This study aimed to evaluate 2 commercial assays for HPV detection and typing using FFPE cervical specimens.

METHODS

Four large North Carolina pathology laboratories provided FFPE specimens from 299 women ages18 and older diagnosed with cervical disease from 2001 to 2006. For each woman, one diagnostic block was selected and unstained serial sections were prepared for DNA typing. Extracts from samples with residual lesion were used to detect and type HPV using parallel and serial testing algorithms with the Linear Array and LiPA HPV genotyping assays.

FINDINGS

LA and LiPA concordance was 0.61 for detecting any high-risk (HR) and 0.20 for detecting any low-risk (LR) types, with significant differences in marginal proportions for HPV16, 51, 52, and any HR types. Discordant results were most often LiPA-positive, LA-negative. The parallel algorithm yielded the highest prevalence of any HPV type (95.7%). HR type prevalence was similar using parallel (93.1%) and serial (92.1%) approaches. HPV16, 33, and 52 prevalence was slightly lower using the serial algorithm, but the median number of HR types per woman (1) did not differ by algorithm. Using the serial algorithm, HPV DNA was detected in >85% of invasive and >95% of pre-invasive lesions. The most common type was HPV16, followed by 52, 18, 31, 33, and 35; HPV16/18 was detected in 56.5% of specimens. Multiple HPV types were more common in lower grade lesions.

CONCLUSIONS

We developed an efficient algorithm for testing and reporting results of two commercial assays for HPV detection and typing in FFPE specimens, and describe HPV type distribution in pre-invasive and invasive cervical lesions in a state-based sample prior to HPV vaccine introduction.

Minimum data elements for research reports on CFS

Chronic fatigue syndrome (CFS) is a debilitating condition that has received increasing attention from researchers in the past decade. However, it has become difficult to compare data collected in different laboratories due to the variability in basic information regarding descriptions of sampling methods, patient characteristics, and clinical assessments. The issue of variability in CFS research was recently highlighted at the NIH's 2011 State of the Knowledge of CFS meeting prompting researchers to consider the critical information that should be included in CFS research reports. To address this problem, we present our consensus on the minimum data elements that should be included in all CFS research reports, along with additional elements that are currently being evaluated in specific research studies that show promise as important patient descriptors for subgrouping of CFS. These recommendations are intended to improve the consistency of reported methods and the interpretability of reported results. Adherence to minimum standards and increased reporting consistency will allow for better comparisons among published CFS articles, provide guidance for future research and foster the generation of knowledge that can directly benefit the patient.

Monitoring HPV type-specific prevalence over time through clinic-based surveillance: a perspective on vaccine effectiveness

We investigated the feasibility of monitoring trends in prevalence of vaccine-preventable human papillomavirus (HPV) types in different clinic populations. We collected cervical specimens from women presenting to family planning, primary care, and sexually transmitted disease (STD) clinics for routine pap smears in five US cities during 2003-2005. We performed HPV genotyping and calculated annual type-specific prevalences; pre-vaccine era prevalence was highest for HPV 16 (6.0; 95% confidence interval [CI] 5.5-6.6%) and annual prevalences for vaccine-preventable types were stable, with few exceptions, after controlling for clinic type, age group, and city. With sufficient sample size and stable population characteristics, clinic-based surveillance systems can contribute to monitoring HPV vaccine impact in the cervical screening population.

Age-group differences in human papillomavirus types and cofactors for cervical intraepithelial neoplasia 3 among women referred to colposcopy

BACKGROUND

Recommendations for high-risk human papillomavirus (HR-HPV) testing as an adjunct to cytology for cervical cancer screening differ by age group, because HR-HPV tests lack adequate specificity in women aged <30. Here, we assess age-group differences in HPV types and other risk factors for cervical intraepithelial neoplasia (CIN) grade 3 or worse (CIN3+) versus CIN0-2 in women from four colposcopy clinics.

METHODS

Women ages 18 to 69 (n = 1,658) were enrolled and completed structured interviews to elicit data on behavioral risk factors prior to their examinations. HPV genotyping was done on exfoliated cervical cell samples. We estimated relative risks (RR) for HPV types and cofactors for CIN3+, overall and stratified by age group.

RESULTS

After 2 years of follow-up, we identified 178 CIN3+, 1,305 CIN0-2, and 175 indeterminate outcomes. Nonvaccine HR-HPV types were only associated with CIN3+ among women ≥ 30 (RR = 2.3, 95% CI: 1.5-3.4; <30: RR = 0.9). Among all HR-HPV-positive women, adjusting for age, significant cofactors for CIN3+ included current smoking (RR = 1.5), former smoking (RR = 1.8), regular Pap screening (RR = 0.7), current regular condom use (RR = 0.5), and parity ≥ 5 (RR = 1.6, P(trend) for increasing parity = 0.07). However, the parity association differed by age group (≥ 30: RR = 1.8, P(trend) = 0.008; <30: RR = 0.9; P(trend) =.55).

CONCLUSION

Subgroup variation by age in the risk of CIN3+ points to the importance of the timing of exposures in relation to CIN3+ detection.

IMPACT

Future screening strategies need to consider natural history and secular trends in cofactor prevalence in the pursuit of appropriately sensitive and specific screening tools applied to appropriate age groups.