RESUMEN
BACKGROUND: We assessed the incidence and risk factors for first detection and redetection with the same human papillomavirus (HPV) genotype, and prevalence of cytological lesions during HPV redetections. METHODS: The Ludwig-McGill cohort study followed women aged 18-60 years from São Paulo, Brazil in 1993-1997 for up to 10 years. Women provided cervical samples for cytology testing and HPV DNA testing at each visit. A redetection was defined as a recurring genotype-specific HPV positive result after 1 or more intervening negative visits. Predictors of genotype-specific redetection were assessed using adjusted hazard ratios (aHR) with Cox regression modeling. RESULTS: In total, 2184 women contributed 2368 incident HPV genotype-specific first detections and 308 genotype-specific redetections over a median follow-up of 6.5 years. The cumulative incidence of redetection with the same genotype was 6.6% at 1 year and 14.8% at 5 years after the loss of positivity of the first detection. Neither age (aHR 0.90; 95% confidence interval [CI], .54-1.47 for ≥45 years vs < 25 years) nor new sexual partner acquisition (aHR 0.98; 95% CI, .70-1.35) were statistically associated with genotype-specific redetection. High-grade squamous intraepithelial lesion prevalence was similar during first HPV detections (2.9%) and redetection (3.2%). CONCLUSIONS: Our findings suggest many HPV redetections were likely reactivations of latent recurring infections.
Asunto(s)
Infecciones por Papillomavirus , Neoplasias del Cuello Uterino , Adulto , Femenino , Humanos , Brasil/epidemiología , Estudios de Cohortes , Virus del Papiloma Humano , Recurrencia Local de Neoplasia/complicaciones , Papillomaviridae/genética , Factores de Riesgo , Adolescente , Adulto Joven , Persona de Mediana EdadRESUMEN
Income, a component of socioeconomic status, influences cancer risk as a social determinant of health. We evaluated the independent associations between individual- and area-level income and site-specific cancer incidence in Canada. We used data from the 2006 and 2011 Canadian Census Health and Environment Cohorts, which are probabilistically linked datasets constituted by 5.9 million and 6.5 million respondents of the 2006 Canadian long-form census and 2011 National Household Survey, respectively. Individuals were linked to the Canadian Cancer Registry through 2015. Individual-level income was derived using after-tax household income adjusted for household size. Annual tax return postal codes were used to assign area-level income quintiles to individuals for each year of follow-up. We calculated age-standardized incidence rates (ASIR) and rate ratios for cancers overall and by site. We conducted multivariable negative binomial regression to adjust these rates for other demographic and socioeconomic variables. Individuals of lower individual- and area-level income had higher ASIRs compared to those in the wealthiest income quintile for head and neck, oropharyngeal, esophageal, stomach, colorectal, anal, liver, pancreas, lung, cervical and kidney and renal pelvis cancers. Conversely, individuals of wealthier individual- and area-level income had higher ASIRs for melanoma, leukemia, Hodgkin's lymphoma, non-Hodgkin's lymphoma, breast, uterine, prostate and testicular cancers. Most differences in site-specific incidence by income quintile remained after adjustment. Although Canada's publicly funded healthcare system provides universal coverage, inequalities in cancer incidence persist across individual- and area-level income gradients. Our estimates suggest that individual- and area-level income affect cancer incidence through independent mechanisms.
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Renta , Melanoma , Masculino , Humanos , Incidencia , Canadá/epidemiología , Clase Social , Factores SocioeconómicosRESUMEN
Human papillomaviruses (HPV) of the genus Betapapillomavirus can infect both cutaneous and mucosal sites, but research on their natural history at mucosal sites remains scarce. We examined the risk factors and co-detection patterns of HPVs of the Betapapillomavirus and Alphapapillomavirus genera in cervical samples of the Ludwig-McGill cohort study. We assessed a subset of 505 women from the Ludwig-McGill cohort study from São Paulo, Brazil. Cervical samples over the first year of follow-up were tested for DNA of over 40 alphapapillomavirus types and 43 betapapillomavirus types using a type-specific multiplex genotyping polymerase chain reaction assay. We assessed the risk factors for prevalent and incident betapapillomavirus type detection, and whether types were detected more frequently together than expected assuming independence using permutation tests, logistic regression, and Cox regression. We observed significant within-genus clustering but not cross-genus clustering. Multiple betapapillomavirus types were co-detected in the same sample 2.24 (95% confidence interval [CI]: 1.65-3.29) times more frequently than expected. Conversely, co-detections of alphapapillomavirus and betapapillomavirus types in the same sample occurred only 0.64 (95% CI: 0.51-0.83) times as often as expected under independence. In prospective analyses, positivity to one HPV genus was associated with a nonsignificant lower incidence of detection of types in the other genus. Lifetime number of sex partners and new sex partner acquisition were associated with lower risks of prevalent and incident betapapillomavirus detection. Betapapillomaviruses are commonly found in the cervicovaginal tract. Results suggest potentially different mechanisms of transmission for betapapillomavirus genital infections other than vaginal sex.
Asunto(s)
Alphapapillomavirus , Betapapillomavirus , Infecciones por Papillomavirus , Humanos , Adulto , Femenino , Betapapillomavirus/genética , Alphapapillomavirus/genética , Estudios de Cohortes , Infecciones por Papillomavirus/epidemiología , Estudios Prospectivos , Brasil/epidemiología , Virus del Papiloma HumanoRESUMEN
BACKGROUND: Infections with human papillomaviruses (HPVs) may enter a latent state, and eventually become reactivated following loss of immune control. It is unclear what proportion of incident HPV detections are reactivations of previous latent infections vs new transmissions. METHODS: The HPV Infection and Transmission among Couples through Heterosexual activity (HITCH) cohort study prospectively followed young newly formed heterosexual partners recruited between 2005 and 2011 in Montréal, Canada. We calculated the fraction of incident HPV detections nonattributable to sexual transmission risk factors with a Bayesian Markov model. Results are the median (2.5th-97.5th percentiles) of the estimated posterior distribution. RESULTS: A total of 544 type-specific incident HPV detection events occurred in 849 participants; 33% of incident HPV detections occurred in participants whose HITCH partners were negative for that HPV type and who reported no other sex partners over follow-up. We estimate that 43% (38%-48%) of all incident HPV detections in this population were not attributable to recent sexual transmission and might be potentially reactivation of latent infections. CONCLUSIONS: A positive HPV test result in many cases may be a reactivated past infection, rather than a new infection from recent sexual behaviors or partner infidelity. The potential for reactivation of latent infections in previously HPV-negative women should be considered in the context of cervical cancer screening.
Asunto(s)
Alphapapillomavirus , Infección Latente , Infecciones por Papillomavirus , Enfermedades de Transmisión Sexual , Neoplasias del Cuello Uterino , Teorema de Bayes , Estudios de Cohortes , Detección Precoz del Cáncer , Femenino , Genitales , Humanos , Papillomaviridae/genética , Infecciones por Papillomavirus/diagnóstico , Infecciones por Papillomavirus/epidemiología , Factores de Riesgo , Conducta Sexual , Parejas Sexuales , Neoplasias del Cuello Uterino/diagnóstico , Neoplasias del Cuello Uterino/epidemiologíaRESUMEN
The COVID-19 pandemic has affected cancer care worldwide. This study aimed to estimate the long-term impacts of cancer care disruptions on cancer mortality in Canada using a microsimulation model. The model simulates cancer incidence and survival using cancer incidence, stage at diagnosis and survival data from the Canadian Cancer Registry. We modeled reported declines in cancer diagnoses and treatments recorded in provincial administrative datasets in March 2020 to June 2021. Based on the literature, we assumed that diagnostic and treatment delays lead to a 6% higher rate of cancer death per 4-week delay. After June 2021, we assessed scenarios where cancer treatment capacity returned to prepandemic levels, or to 10% higher or lower than prepandemic levels. Results are the median predictions of 10 stochastic simulations. The model predicts that cancer care disruptions during the COVID-19 pandemic could lead to 21 247 (2.0%) more cancer deaths in Canada in 2020 to 2030, assuming treatment capacity is recovered to 2019 prepandemic levels in 2021. This represents 355 172 life years lost expected due to pandemic-related diagnostic and treatment delays. The largest number of expected excess cancer deaths was predicted for breast, lung and colorectal cancers, and in the provinces of Ontario, Québec and British Columbia. Diagnostic and treatment capacity in 2021 onward highly influenced the number of cancer deaths over the next decade. Cancer care disruptions during the COVID-19 pandemic could lead to significant life loss; however, most of these could be mitigated by increasing diagnostic and treatment capacity in the short-term to address the service backlog.
Asunto(s)
COVID-19/terapia , Neoplasias/terapia , Femenino , Humanos , Incidencia , Masculino , Neoplasias/mortalidad , Pandemias , SARS-CoV-2 , Análisis de Supervivencia , Tiempo de TratamientoRESUMEN
In their accompanying article, Vänskä et al. (Am J Epidemiol. 2021;190(4):506-514) provide us with cohort lifetime risks of cervical cancer attributable to different types of human papillomavirus in Sweden. We argue that a standardized lifetime risk such as those calculated by Vänskä et al. might be a more appropriate public health target for cervical cancer elimination than age-standardized incidence rates. Age standardization to an arbitrary standard age distribution implies an implicit value choice regarding the weight of different age groups for which we find little moral justification. Conversely, a standardized lifetime risk uses standard life expectancy as a weight, corresponding to the likelihood that cervical cancer would impact a woman and prevent her from pursuing opportunities within a standard life span. Based on the data from Vänskä et al., a standardized lifetime risk of 129-250 cervical cancers per 100,000 women born could be an aspirational alternative public health target for cervical cancer elimination as a public health problem, complementary to the World Health Organization's arbitrary draft target of 4 cervical cancers per 100,000 age-standardized woman-years.
Asunto(s)
Alphapapillomavirus , Infecciones por Papillomavirus , Neoplasias del Cuello Uterino , Factores de Edad , Femenino , Humanos , Incidencia , Papillomaviridae , Infecciones por Papillomavirus/epidemiología , Suecia/epidemiología , Neoplasias del Cuello Uterino/epidemiología , Neoplasias del Cuello Uterino/prevención & controlRESUMEN
BACKGROUND: It is unclear whether sexual transmission rates of human papillomaviruses (HPV) differ between sexes and HPV types. We estimate updated transmission rates from the final HITCH cohort study and propose an estimation method that accounts for interval-censored data and infection clearance. METHODS: We enrolled young women 18-24 years old and their male sex partners ≥18 years old in Montréal, Canada, between 2005 and 2011. We followed women over 24 months and men over 4 months. We tested genital samples with Linear Array for HPV DNA detection and genotyping. We calculated infection transmission rates between partners using a multistate Markov model via a Bayesian approach. We report the posterior median and 2.5%-97.5% percentile intervals (95% PI). RESULTS: We observed 166 type-specific incident HPV transmission events in 447 women and 402 men. The estimated median transmission rate from an HPV-positive to a negative partner was 4.2 (95% PI = 3.1 to 5.3) per 100 person-months. The transmission rate from men-to-women was 3.5 (95% PI = 2.5 to 4.7) and from women-to-men was 5.6 (95% PI = 3.8 to 7.0) per 100 person-months, corresponding to a rate ratio of 1.6 (95% PI = 1.0 to 2.5). Partners reporting always using condoms had a 0.22 (95% PI = 0.05 to 0.61) times lower HPV transmission rate than those reporting never using condoms. HPV16/18 did not have particularly high transmission rates relative to other HPV types. CONCLUSION: Our updated analysis supports previous research suggesting higher women-to-men than men-to-women HPV transmission rates and a protective effect of condoms in heterosexual partnerships. Our results also suggest that crude incidence rates underestimate HPV transmission rates due to interval-censoring. See video abstract at http://links.lww.com/EDE/B794.
Asunto(s)
Alphapapillomavirus , Infecciones por Papillomavirus , Adolescente , Adulto , Teorema de Bayes , Canadá/epidemiología , Estudios de Cohortes , Femenino , Genitales , Heterosexualidad , Papillomavirus Humano 16/genética , Papillomavirus Humano 18 , Humanos , Incidencia , Masculino , Infecciones por Papillomavirus/epidemiología , Conducta Sexual , Parejas Sexuales , Adulto JovenRESUMEN
Most women positive for human papillomavirus (HPV) are cytology normal. The optimal screen-management of these women is unclear given their risk of developing precancer. We performed a systematic review and meta-analysis of progression rates to precancer and cancer for HPV-positive, cytology normal women. We searched MEDLINE, EMBASE and Scopus for prospective studies measuring the cumulative incidence of precancer and cervical cancer in HPV-positive, cytology/histology normal women. Record screening was performed independently by two reviewers. We modeled the cumulative incidence over time using a multilevel random-effects meta-regression model. We used the model to predict HPV type-specific risks of precancer and cancer over follow-up. Data from 162 unique records were used in our analysis. The average incidence rate of cervical intraepithelial neoplasia grade 3 or cancer (CIN3+) in high-risk HPV positive but cytology/histology normal women was 1.0 per 100 women-years (95% CI: 1.0-1.1). This corresponds to an average cumulative risk at 1, 3 and 5 years of 2.1% (95% prediction interval 0.0-9.5), 4.3% (95% prediction interval 0.0-11.5) and 6.4% (95% prediction interval 0.0-13.5). HPV type was a strong predictor of the risk of oncogenic progression. There was substantial heterogeneity in the background precancer risk across studies (P-value < .0001). Our HPV type-specific progression risk estimates can help inform risk-based cervical cancer screening guidelines for HPV-positive women. However, precancer and cervical cancer risks are highly variable and may not be generalizable between populations.
Asunto(s)
Alphapapillomavirus/aislamiento & purificación , Infecciones por Papillomavirus/epidemiología , Displasia del Cuello del Útero/epidemiología , Neoplasias del Cuello Uterino/epidemiología , Alphapapillomavirus/genética , ADN Viral/genética , Femenino , Humanos , Clasificación del Tumor , Estudios Observacionales como Asunto , Prevalencia , Ensayos Clínicos Controlados Aleatorios como Asunto , Neoplasias del Cuello Uterino/patología , Neoplasias del Cuello Uterino/virología , Displasia del Cuello del Útero/patología , Displasia del Cuello del Útero/virologíaRESUMEN
OBJECTIVE: We assessed whether human papillomavirus (HPV) viral load is an independent predictor of underlying cervical disease and its diagnostic accuracy by age. METHODS: The Biomarkers of Cervical Cancer Risk study was a case-control study from 2001 to 2010 in Montréal, Canada. Cases were histologically-confirmed cervical intraepithelial neoplasia (CIN), adenocarcinoma in situ (AIS), or cervical cancer cases. Controls were women presenting for routine screening with normal cytology results. We quantified HPV16/18/31/33/45 viral load from exfoliated cervical cells using a real-time PCR assay. Diagnostic accuracy of viral load was assessed using the area under the receiver operating characteristic curve (AUC). We restricted the analysis to the 632 cases and controls who were HPV16/18/31/33/45 positive. RESULTS: Geometric mean HPV16/18/31/33/45 viral load increased with severity of lesion grade, ranging from 0.7, 3.1, 4.8, 7.2, and 12.4 copies/cell in normal, CIN1, CIN2, CIN3&AIS, and cervical cancer respectively. The adjusted odds ratio of CIN1+ and CIN2+ increased respectively by 1.3 (95%CI 1.1-1.4) and 1.2 (95%CI 1.1-1.3) per log-transformed viral copy/cell increase of HPV16/18/31/33/45. This association was mainly driven by HPV16, 18, and 31 viral loads. The AUC of HPV16/18/31/33/45 viral load for discriminating between normal and CIN1+ women was 0.70 (95%CI 0.64-0.76) in HPV-positive women, and was 0.76 (95%CI 0.66-0.86) for women ≥30â¯years and 0.66 (95%CI 0.58-0.74) for women under 30â¯years. CONCLUSIONS: HPV viral load has lower diagnostic accuracy than has been reported for other HPV screening triage tests. However, it may be useful for triaging HPV tests in settings without cytology results such as HPV self-sampling.
Asunto(s)
Adenocarcinoma in Situ/virología , Alphapapillomavirus/aislamiento & purificación , Infecciones por Papillomavirus/virología , Displasia del Cuello del Útero/virología , Neoplasias del Cuello Uterino/virología , Adulto , Anciano , Área Bajo la Curva , Estudios de Casos y Controles , Femenino , Humanos , Persona de Mediana Edad , Quebec , Carga Viral/fisiología , Adulto JovenRESUMEN
BACKGROUND: There is a paucity of empirical evidence to inform the age at which to stop cervical cancer screening. The recommended age to stop screening generally varies between age 50-70 years worldwide. However, cervical cancer incidence and mortality remain high in older women. We used a Markov model of cervical cancer screening to estimate the remaining lifetime risk of cervical cancer at different ages and with different exit screening tests, with the aim of informing recommendations of the age at which to stop cervical cancer screening in developed countries. METHODS: For this modelling study, we developed a state transition (Markov) model of cervical cancer natural history and screening. We developed, calibrated, and validated our model using Canadian provincial registries and survey data. To simulate an age-structured population in the model, a new cohort of 236â564 women (one fifth of the population of Canadian women aged 20-24 years in 2012) entered the model every year and were successively modelled in parallel. Successive cohorts entered the model at age 10 years, creating an age-structured population of women aged 10-100 years. Women who had a total hysterectomy were excluded from the analyses. We calibrated our model to human papillomavirus (HPV) infection and cancer incidence with data from Statistics Canada, which compiles the data from 13 individual provincial registries. We chose a three-stage progressive cervical intraepithelial neoplasia model to include differences in management and treatment decisions depending on lesion severity. We modelled infections with four high-risk HPV groups: HPV16 and HPV18; HPV31, HPV33, HPV45, HPV52, and HPV58; HPV35, HPV39, HPV51, HPV56, HPV59, HPV66, and HPV68; and a generic group of other potentially oncogenic HPVs. We estimated 5-year, 10-year, and remaining lifetime risk of cervical cancer for older, unvaccinated women who stopped screening at different ages and underwent different screening tests. FINDINGS: Cervical cancer incidence excluding women with hysterectomies underestimated the incidence of cervical cancer in women with a cervix by up to 71% in women aged 80-84 years. Our model predicted that women without HPV vaccination who have been never screened have a 1 in 45 (95% percentile interval 1 in 32 to 1 in 64) lifetime risk of cervical cancer. Perfect adherence (100% of women screened) to cytology screening every 3 years between the ages of 25 years and 69 years could reduce the lifetime risk of cervical cancer to 1 in 532 women (95% percentile interval 1 in 375 to 1 in 820) without HPV vaccination. Increasing the age at which women stopped cytology screening from 55 years to 75 years led to incremental decreases in cancer risk later in life. A 70-year old woman whose screening history was unknown had an average remaining lifetime risk of 1 in 588 (<1%; 95% percentile interval 1 in 451 to 1 in 873) if she stopped screening. Her remaining lifetime risk at age 70 years was reduced to 1 in 1206 (2·0 times reduction; 95% percentile interval 1 in 942 to 1 in 1748) if she had a negative cytology test, 1 in 6525 (12·9 times reduction; 95% percentile interval 1 in 3167 to 1 in 18â664) if she had a negative HPV test, and 1 in 9550 (18·1 times reduction; 95% percentile interval 1 in 4928 to 1 in 23â228) if she had a negative co-test for cytology and HPV. INTERPRETATION: Cervical cancer risk reductions might be achieved by screening with cytology up to age 75 years, although with diminishing returns. A negative exit oncogenic HPV test or negative HPV test plus cytology correlates with a low remaining lifetime cervical cancer risk for unvaccinated women with a cervix after the age of 55 years. FUNDING: Canadian Institutes of Health Research.
Asunto(s)
Detección Precoz del Cáncer/métodos , Neoplasias del Cuello Uterino/diagnóstico , Adolescente , Adulto , Distribución por Edad , Factores de Edad , Anciano , Anciano de 80 o más Años , Niño , Toma de Decisiones Clínicas , Detección Precoz del Cáncer/normas , Femenino , Pruebas de ADN del Papillomavirus Humano , Humanos , Incidencia , Cadenas de Markov , Persona de Mediana Edad , Prueba de Papanicolaou , Infecciones por Papillomavirus/diagnóstico , Infecciones por Papillomavirus/epidemiología , Infecciones por Papillomavirus/virología , Valor Predictivo de las Pruebas , Pronóstico , Medición de Riesgo , Factores de Riesgo , Factores Sexuales , Factores de Tiempo , Neoplasias del Cuello Uterino/epidemiología , Neoplasias del Cuello Uterino/virología , Frotis Vaginal , Adulto JovenRESUMEN
BACKGROUND: Y chromosome DNA from male epithelial and sperm cells was detected in vaginal samples after unprotected sex in experimental studies. We assessed the strength of this association in an observational setting to examine the utility of Y chromosome DNA as a biomarker of recent sexual behaviors in epidemiological studies. METHODS: The HPV (human papillomavirus) Infection and Transmission Among Couples Through Heterosexual Activity cohort study enrolled 502 women attending a university or college in Montréal, Canada, and their male partners from 2005 to 2010. Participants completed self-administered questionnaires. We used real-time polymerase chain reaction to test women's baseline vaginal samples for Y chromosome DNA and assessed which sexual behaviors were independent predictors of Y chromosome DNA positivity and quantity with logistic and negative binomial regression. RESULTS: Y chromosome DNA positivity decreased from 77% in women in partnerships reporting vaginal sex 0 to 1 day ago to 13% in women in partnerships reporting last vaginal sex of 15 or more days ago (adjusted odds ratio, 0.09; 95% confidence interval, 0.02-0.36). The mean proportion of exfoliated vaginal sample cells with Y chromosome DNA was much lower for women who reported always using condoms (0.01%) than for women who reported never using condoms (2.07%) (adjusted ratio, 26.8; 95% confidence interval, 8.9-80.5). No association was found with reported oral/digital sex frequency or concurrency of partnerships. CONCLUSIONS: Y chromosome DNA quantity is strongly associated with days since last vaginal sex and lack of condom use in observational settings. Y chromosome DNA quantity may prove useful as a correlate of recent vaginal sex in observational studies lacking data on sexual behavior, such as surveillance studies of human papillomavirus infection prevalence.
Asunto(s)
Cromosomas Humanos Y/genética , Coito , Condones/estadística & datos numéricos , ADN/análisis , Heterosexualidad , Infecciones por Papillomavirus/transmisión , Parejas Sexuales , Vagina/metabolismo , Biomarcadores/análisis , Canadá , Femenino , Papillomavirus Humano 16/aislamiento & purificación , Humanos , Masculino , Oportunidad Relativa , Infecciones por Papillomavirus/virología , Reacción en Cadena de la Polimerasa , Vigilancia de la Población , Valor Predictivo de las Pruebas , Prevalencia , Factores de Riesgo , Encuestas y Cuestionarios , Vagina/virología , Adulto JovenRESUMEN
Background: Detection of human papillomavirus (HPV) DNA in genital samples may not always represent true infections but may be depositions from infected sexual partners. We examined whether sexual risk factors and a biomarker (Y chromosome DNA) were associated with genital HPV partner concordance and estimated the fraction of HPV detections potentially attributable to partner deposition. Methods: The HITCH study enrolled young women attending a university or college in Montréal, Canada, and their male partners, from 2005 to 2010. We tested baseline genital samples for Y chromosome DNA and HPV DNA using polymerase chain reaction. Results: Type-specific HPV concordance was 42.4% in partnerships where at least one partner was HPV DNA positive. Y chromosome DNA predicted type-specific HPV concordance in univariate analyses, but in multivariable models the independent predictors of concordance were days since last vaginal sex (26.5% higher concordance 0-1 vs 8-14 days after last vaginal sex) and condom use (22.6% higher concordance in never vs always users). We estimated that 14.1% (95% confidence interval [CI], 6.3-21.9%) of HPV DNA detections in genital samples were attributable to vaginal sex in the past week. Conclusions: A substantial proportion of HPV DNA detections may be depositions due to recent unprotected vaginal sex.
Asunto(s)
Alphapapillomavirus/genética , Infecciones por Papillomavirus/epidemiología , Infecciones por Papillomavirus/virología , Conducta Sexual , Parejas Sexuales , Adolescente , Adulto , Alphapapillomavirus/clasificación , Biomarcadores , Canadá/epidemiología , Cromosomas Humanos Y , ADN Viral , Femenino , Humanos , Masculino , Infecciones por Papillomavirus/transmisión , Vigilancia de la Población , Prevalencia , Factores de Riesgo , Vagina/virología , Adulto JovenRESUMEN
BACKGROUND: Assortative sexual mixing, the tendency for individuals to choose partners with similar characteristics to themselves, may be an important contributor to the unequal distribution of sexually transmitted infections in populations. We analyzed the tendency for assortative mixing on demographic and sexual behaviors characteristics in newly formed young adults dating partnerships. METHODS: Women aged 18 to 24 years and their male sexual partners of no more than 6 months were recruited during 2005 to 2010 at universities in Montreal, Canada. New dating partners were also prospectively recruited during the 2-year follow-up. We used Spearman and Newman coefficients to examine correlations between partners' demographic characteristics and sexual behaviors, and multivariable logistic modeling to determine which characteristics were assortative. RESULTS: Participants in 502 recruited partnerships were assortative on age (Spearman P = 0.60), smoking behavior (P = 0.43), ethnicity (Newman coefficient=0.39), lifetime number of sexual partners (P = 0.36), sex partner acquisition rates (P = 0.22), gap length between partnerships (P = 0.20), and on whether they had concurrent partners (P = 0.33). Partners were assortative on number of lifetime partners, sexual partner acquisition rates, concurrency, and gap length between partnerships even after adjustment for demographic characteristics. Reported condom use was correlated between initial and subsequently recruited partners (P = 0.35). There was little correlation between the frequencies of vaginal/oral/digital/anal sex between subsequent partnerships. CONCLUSIONS: Dating partnerships were substantially assortative on various sexual behaviors as well as demographic characteristics. Though not a representative population sample, our recruitment of relatively new partnerships reduces survivor bias inherent to cross-sectional surveys where stable long-term partnerships are more likely to be sampled.
Asunto(s)
Etnicidad/estadística & datos numéricos , Heterosexualidad , Infecciones por Papillomavirus/transmisión , Parejas Sexuales , Canadá/epidemiología , Condones/estadística & datos numéricos , Femenino , Estudios de Seguimiento , Humanos , Relaciones Interpersonales , Masculino , Grupo Paritario , Satisfacción Personal , Estudios Prospectivos , Parejas Sexuales/psicología , Conducta Social , Adulto JovenAsunto(s)
Alphapapillomavirus , Infecciones por Papillomavirus , Displasia del Cuello del Útero , Neoplasias del Cuello Uterino , Colposcopía , Femenino , Humanos , Papillomaviridae/genética , Infecciones por Papillomavirus/complicaciones , Infecciones por Papillomavirus/epidemiología , Embarazo , Neoplasias del Cuello Uterino/epidemiología , Displasia del Cuello del Útero/epidemiologíaRESUMEN
The clustering of human papillomavirus (HPV) infections in some individuals is often interpreted as the result of common risk factors rather than biological interactions between different types of HPV. The intraindividual correlation between times-at-risk for all HPV infections is not generally considered in the analysis of epidemiologic studies. We used a deterministic transmission model to simulate cross-sectional and prospective epidemiologic studies measuring associations between 2 HPV types. When we assumed no interactions, the model predicted that studies would estimate odds ratios and incidence rate ratios greater than 1 between HPV types even after complete adjustment for sexual behavior. We demonstrated that this residual association is due to correlation between the times-at-risk for different HPV types, where individuals become concurrently at risk for all of their partners' HPV types when they enter a partnership and are not at risk when they are single. This correlation can be controlled in prospective studies by restricting analyses to susceptible individuals with an infected sexual partner. The bias in the measured associations was largest in low-sexual-activity populations, cross-sectional studies, and studies which evaluated infection with a first HPV type as the exposure. These results suggest that current epidemiologic evidence does not preclude the existence of competitive biological interactions between HPV types.
Asunto(s)
Coinfección , Interacciones Microbianas , Infecciones por Papillomavirus/transmisión , Conducta Sexual/estadística & datos numéricos , Enfermedades Virales de Transmisión Sexual/transmisión , Interferencia Viral , Sesgo , Estudios Epidemiológicos , Humanos , Modelos Biológicos , Papillomaviridae/clasificación , Papillomaviridae/inmunología , Infecciones por Papillomavirus/epidemiología , Infecciones por Papillomavirus/inmunología , Infecciones por Papillomavirus/virología , Factores de Riesgo , Parejas Sexuales , Enfermedades Virales de Transmisión Sexual/epidemiología , Enfermedades Virales de Transmisión Sexual/inmunología , Enfermedades Virales de Transmisión Sexual/virología , Factores de TiempoRESUMEN
Cervical cancer is the first cancer deemed amenable to elimination through prevention, and thus lessons from the epidemiology and prevention of this cancer type can provide information on strategies to manage other cancers. Infection with the human papillomavirus (HPV) causes virtually all cervical cancers, and an important proportion of oropharyngeal, anal and genital cancers. Whereas 20th century prevention efforts were dominated by cytology-based screening, the present and future of HPV-associated cancer prevention relies mostly on HPV vaccination and molecular screening tests. In this Review, we provide an overview of the epidemiology of HPV-associated cancers, their disease burden, how past and contemporary preventive interventions have shaped their incidence and mortality, and the potential for elimination. We particularly focus on the cofactors that could have the greatest effect on prevention efforts, such as parity and human immunodeficiency virus infection, as well as on social determinants of health. Given that the incidence of and mortality from HPV-associated cancers remain strongly associated with the socioeconomic status of individuals and the human development index of countries, elimination efforts are unlikely to succeed unless prevention efforts focus on health equity, with a commitment to both primary and secondary prevention.
Asunto(s)
Infecciones por Papillomavirus , Vacunas contra Papillomavirus , Neoplasias del Cuello Uterino , Humanos , Infecciones por Papillomavirus/epidemiología , Infecciones por Papillomavirus/prevención & control , Infecciones por Papillomavirus/virología , Infecciones por Papillomavirus/complicaciones , Femenino , Vacunas contra Papillomavirus/uso terapéutico , Neoplasias del Cuello Uterino/prevención & control , Neoplasias del Cuello Uterino/epidemiología , Neoplasias del Cuello Uterino/virología , Incidencia , Papillomaviridae/patogenicidad , Detección Precoz del Cáncer , Neoplasias/epidemiología , Neoplasias/prevención & control , Neoplasias/virologíaRESUMEN
Background: Life expectancy prediction is important for end-of-life planning. Established methods (Palliative Performance Scale [PPS], Palliative Prognostic Index [PPI]) have been validated for intermediate- to long-term prognoses, but last-weeks-of-life prognosis has not been well studied. Patients admitted to a palliative care facility often have a life expectancy of less than three weeks. Reliable last-weeks-of-life prognostic tools are needed. Objective: To improve short-term survival prediction in terminally ill patients. Method: This prospective study included all patients admitted to a palliative care facility in Montreal, Canada, over one year. PPS and PPI were assessed until patients' death. Seven prognostic clinical signs of impending death (Short-Term Prognosis Signs [SPS]) were documented daily. Results: The analyses included 273 patients (76% cancer). The median survival time for a PPS ≤20% was 2.5 days, while for a PPS ≥50% it was 44.5 days, for a PPI >8 the median survival was 3.5 days and for a PPI ≤4 it was 38.5 days. Receiver operating characteristic curves showed a high accuracy in predicting survival. Median survival after the first occurrence of any SPS was below one week. Conclusions: This study demonstrated that the PPS and PPI perform well between one week and three months extending their usefulness to shorter term survival prediction. SPS items provided survival information during the last week of life. Using SPS along with PPS and PPI during the last weeks of life could enable a more precise short-term survival prediction across various end-of-life diagnoses. The translation of this research into clinical practice could lead to a better adapted treatment, the identification of a most appropriate care setting for patients, and improved communication of prognosis with patients and families.
Asunto(s)
Esperanza de Vida , Cuidados Paliativos , Cuidado Terminal , Humanos , Masculino , Femenino , Pronóstico , Estudios Prospectivos , Anciano , Persona de Mediana Edad , Anciano de 80 o más Años , Enfermo Terminal , Quebec , Adulto , Curva ROCRESUMEN
COVID-19 disrupted cancer control worldwide, impacting preventative screening, diagnoses, and treatment services. This modelling study estimates the impact of disruptions on colorectal cancer cases and deaths in Canada and Australia, informed by data on screening, diagnosis, and treatment procedures. Modelling was used to estimate short- and long-term effects on colorectal cancer incidence and mortality, including ongoing impact of patient backlogs. A hypothetical mitigation strategy was simulated, with diagnostic and treatment capacities increased by 5% from 2022 to address backlogs. Colorectal cancer screening dropped by 40% in Canada and 6.3% in Australia in 2020. Significant decreases to diagnostic and treatment procedures were also observed in Australia and Canada, which were estimated to lead to additional patient wait times. These changes would lead to an estimated increase of 255 colorectal cancer cases and 1,820 colorectal cancer deaths in Canada and 234 cases and 1,186 deaths in Australia over 2020-2030; a 1.9% and 2.4% increase in mortality, respectively, vs a scenario with no screening disruption or diagnostic/treatment delays. Diagnostic and treatment capacity mitigation would avert 789 and 350 deaths in Canada and Australia, respectively. COVID-related disruptions had a significant impact on colorectal cancer screening, diagnostic, and treatment procedures in Canada and Australia. Modelling demonstrates that downstream effects on disease burden could be substantial. However, backlogs can be managed and deaths averted with even small increases to diagnostic and treatment capacity. Careful management of resources can improve patient outcomes after any temporary disruption, and these results can inform targeted approaches early detection of cancers.
Asunto(s)
COVID-19 , Neoplasias Colorrectales , Humanos , COVID-19/diagnóstico , COVID-19/epidemiología , Detección Precoz del Cáncer , Neoplasias Colorrectales/diagnóstico , Neoplasias Colorrectales/epidemiología , Neoplasias Colorrectales/terapia , Australia/epidemiología , Canadá/epidemiología , Prueba de COVID-19RESUMEN
Background: Several patients admitted to palliative care residences are on anticoagulotherapy (AC). Given the risks of venous thromboembolism (VTE) and bleeding, the decision to continue or stop AC on admission remains clinically challenging. Objectives: To determine the prevalence of AC use and incidence of suspected VTE and bleeding events in palliative care patients. Methods: Retrospective cohort study including all deceased patients at a Canadian palliative care residence over two years. Results: Among the 453 patients' charts reviewed (369 with cancer), 183 (40%) were on AC at admission or <30 days earlier. Only 64 (35%) continued AC, with 78% discontinuing it during their stay. Demographic parameters were similar in the AC and non-AC groups. The incidence of suspected VTE was lower in patients pursuing AC post-admission than in those who stopped: (4.6% vs. 6.7%) and, conversely, the incidence of bleeding was higher in patients on AC: (10.8% vs. 7.6%), though these differences were not statistically significant. The risk of death in cancer patients within 72 hours of suspected VTE or bleeding event was 80% and 30%, respectively. Patients on AC had a 33% reduced risk of VTE but a 44% increased risk of bleeding. Conclusion: This study provides information on the AC use in palliative care patients. In term of survivorship, it suggests a possible advantage to continue AC to prevent a symptomatic or distressing death. Given the low incidence of events, larger powered studies will be necessary to further characterize the risks/benefits of pursuing AC in patients in palliative care residences.