Background: HPV burden is a predictor for high-grade cervical intraepithelial neoplasia and cancer. The natural history of HPV load in young women being recently exposed to HPV is described in this paper.Methods: A total of 636 female university students were followed for 2 years. Cervical specimens with HPV-16, -18, -31, or -45 DNA by consensus PCR were further evaluated with type-specific and β-globin real-time PCR assays. Proportional hazards regression was used to estimate hazard ratios (HR) of infection clearance. Generalized estimating equations assessed whether HPV loads was predictive of HPV infection at the subsequent visit.Results: HPV loads were consistently higher among women <25 years old, and those who had multiple sex partners, multiple HPV type infections and smokers. HPV-16 integration was encountered only in one sample. Infection clearance was faster among women at lower tertiles of HPV-16 (HR = 2.8, 95%CI: 1.0-8.1), HPV-18 (HR = 3.5, 95%CI: 1.1-11.2) or combined (HR = 2.4, 95%CI: 1.8-6.2) DNA loads. The relationship between HPV-16 and HPV-18 DNA loads and infection clearance followed a clear dose-response pattern, after adjusting for age and number of sexual partners. GEE Odds Ratios for HPV persistence of the middle and upper tertiles relative to the lower tertile were 2.7 and 3.0 for HPV-16 and 3.8 and 39.1 for HPV-18, respectively. There was no association between HPV-31 or -45 DNA loads and persistence.Conclusions: The association between HPV load and persistence is not uniform across high-risk genital genotypes. HPV-16 integration was only rarely demonstrated in young women.
Objective: The aim of the study was to quantify baseline estradiol (E2) and estrone (E1) concentrations according to selected patient characteristics in a substudy nested within the MAP.3 chemoprevention trial. Methods: E2 and E1 levels were measured in 4,068 postmenopausal women using liquid chromatography-tandem mass spectrometry. Distributions were described by age, years since menopause, race, body mass index (BMI), smoking status, and use and duration of hormone therapy using the Kruskal-Wallis test. Multivariable linear regression was also used to identify characteristics associated with estrogen levels. Results: After truncation at the 97.5th percentile, the mean (SD)/median (IQR) values for E2 and E1 were 5.41 (4.67)/4.0 (2.4-6.7) pg/mL and 24.7 (14.1)/21 (15-31) pg/mL, respectively. E2 and E1 were strongly correlated (Pearson correlation [r] = 0.8, P < 0.01). The largest variation in E2 and E1 levels was by BMI; mean E2 and E1 levels were 3.5 and 19.1 pg/mL, respectively for women with BMI less than 25 and 7.5 and 30.6 pg/mL, respectively, for women with BMI greater than 30. E2 and E1 varied by age, BMI, smoking status, and prior hormone therapy in multivariable models (P < 0.01). Conclusions: There was large interindividual variability observed for E2 and E1 that varied significantly by participant characteristics, but with small absolute differences except in the case of BMI. Although the majority of participant characteristics were independently associated with E1 and E2, together, these factors only explained about 20% of the variation in E1 and E2 levels.
Very few data are available on the determinants of PSA testing in Canada, and it is a matter of debate whether prostate-specific antigen (PSA) screening in asymptomatic men age 50 and older with no risk factors for prostate cancer is useful. If PSA screening is introduced into the periodic health examination, it will be important to know what factors influence its use. The purpose of this study is to determine the factors associated with PSA testing among asymptomatic men age 50 and older participating in the Tomorrow Project in Alberta. The Tomorrow Project is a population-based cohort study with over 11,000 participants accrued in Alberta since February 2003. Information was collected on medical history, sociodemographic factors, health status and lifestyle characteristics. This analysis includes 2136 men 50 years of age and older. The independent association between various factors and recent PSA screening is estimated using logistic regression. Approximately 50% of of the study group had received one or more PSA tests in their lifetime. Of these, 58% were asymptomatic for prostate disease at the time of their most recent PSA test. Variables independently associated with recent PSA screening for prostate cancer in this population include older age (≥ 65 versus < 55 years: adjusted odds ratio [OR] 2.60; 95% confidence interval [CI] 1.77–3.83), higher income (≥ $80,000 versus < $20,000, OR 1.97; 95% CI 1.09–3.55), region of health care delivery, perception of health status (good versus excellent health status; OR 0.65, CI 0.43–0.96], increased number of chronic health conditions (OR 1.73, 95% CI 1.10–2.71), and history of colorectal cancer screening with fecal occult blood test (OR 2.21; 95% CI 1.73–2.83). An increasing proportion of men in Alberta are receiving a PSA test. A number of significant predictors of having a PSA test were identified, suggesting that factors other than having a clinical indication for prostate disease can influence decisions about PSA screening.
We conducted a population-based, retrospective, matched-cohort study to examine the impact of breast cancer diagnosis and treatment on fertility outcomes. Relative risks of infertility, childbirth, premature ovarian insufficiency (POI; age < 40) and early menopause (age < 45) were calculated using modified Poisson regression. Our primary cohort included young women (15–39) with early stage BC diagnosed 1995–2014. Five cancer-free patients were matched to each BC patient by birth year and census subdivision. The BC cohort was further divided by treatment with chemotherapy vs. no chemotherapy treatment. 3903 BC patients and 19,515 cancer-free women. BC patients treated with chemotherapy were at increased risk of infertility (RR 1.81; 95% CI 1.60–2.04), and POI (RR 6.25; 95% CI 5.15–7.58) and decreased childbirth (RR 0.85; 95% CI 0.75–0.96), compared to women without cancer. BC patients who did not receive chemotherapy were also at increased risk of infertility (RR 1.80 95% CI 1.48–2.18) and POI (RR 2.12 95% CI 1.37–3.28). All young BC survivors face an increased risk of diagnosed infertility and POI relative to women without cancer, independent of chemotherapy. These results emphasize the importance of pre-treatment fertility counselling for young women diagnosed with BC.
Genetic variants of insulin-like growth factor 1 (IGF1) pathway genes have been shown to be associated with breast density and IGF1 levels, and therefore may also influence breast cancer risk via pro-survival signalling cascades. The aim of this study was to investigate associations between IGF1 pathway single nucleotide polymorphisms (SNPs) and breast cancer risk among European and East Asian women, and potential interactions with menopausal status and breast tumor subtype. Stratified analyses of 1,037 cases and 1,050 controls from a population-based case-control study were conducted to assess associations with breast cancer for 22 SNPs across five IGF-1 pathway genes in European and East Asian women. Odds ratios were calculated using logistic regression in additive genetic models. Polytomous logistic regression was used to assess heterogeneity by breast tumor subtype. Two SNPs of the IGF1 gene (rs1019731, rs12821878) were associated with breast cancer risk among European women. Four highly linked IGF1 SNPs (rs2288378, rs17727841, rs7136446, rs7956547) were modified by menopausal status among East Asian women only and associated with postmenopausal breast cancers. The association between rs2288378 and breast cancer risk was also modified by breast tumor subtype among East Asian women. Several IGF1 polymorphisms were found to be associated with breast cancer risk and some of these association were modified by menopausal status or breast tumor subtype. Such interactions should be considered when assessing the role of these variants in breast cancer etiology.
Calls to a telephone health helpline (THHL) have been previously evaluated for the ability to monitor specific syndromes, such as fever and influenza-like-illness or gastrointestinal illness. This method of surveillance has been shown to be highly correlated with traditional surveillance methods, and to have potential for early detection of community-based illness. Self-sampling, or having a person take his/her own nasal swab, has also proven successful as a useful method for obtaining a specimen, which may be used for respiratory virus detection. This study describes a self-swabbing surveillance system mediated by a nurse-led THHL in Ontario whereby syndromic surveillance concepts are used to recruit and monitor participants with influenza-like illness. Once recruited, participants collect a nasal specimen obtained by self-swabbing and submit for testing and laboratory confirmation. Enumeration of weekly case counts was used to evaluate the timeliness of the self-swabbing surveillance system through comparison to other respiratory virus and influenza surveillance systems in Ontario. The operational efficiency of the system was also evaluated. The mean and median number of days between the day that a participant called the THHL, to the day a package was received at the laboratory for testing were approximately 10.4 and 8.6 days, respectively. The time between self-swab collection and package reception was 4.9 days on average, with a median of 4 days. The self-swabbing surveillance system adequately captured the 2014 influenza B season in a timely manner when compared to other Ontario-based sources of influenza surveillance data from the same year; however, the emergence of influenza B was not detected any earlier than with these other surveillance systems. Influenza A surveillance was also evaluated. Using the THHL self-swabbing system, a peak in the number of cases for influenza A was observed approximately one week after or during the same week as that reported by the other surveillance systems. This one-year pilot study suggests that the THHL self-swabbing surveillance system has significant potential as an adjunct tool for the surveillance of influenza viruses in Ontario. Recommendations for improving system efficacy are discussed.