74 research outputs found

    What we do and do not know about the menstrual cycle or, questions scientists could be asking

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    The objective of this paper is to consider from a public health perspective the types of questions researchers might be asking about the relationship between menstrual function and women’s health, and to evaluate to the extent to which these questions have or have not been addressed by the scientific community. Based on the findings in this report, it is obvious that a comprehensive program of research is needed in order to begin filling the myriad gaps in scientific knowledge about the menstrual cycle. Given the lack of knowledge about many fundamental aspects of menstrual function and about linkages between the menstrual cycle and other physiologic systems, the importance of conducting basic research cannot be underestimated. The report offers specific recommendations for research priorities

    Modeling Menstrual Cycle Length and Variability at the Approach of Menopause Using Bayesian Changepoint Models

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    As women approach menopause, the patterns of their menstruation cycle lengths change. To study these changes, we need to jointly model both the mean and variability of the cycle length. The model incorporates separate mean and variance change points for each woman and a hierarchical model to link them together, along with regression components to include predictors of menopausal onset such as age at menarche and parity. Data are from TREMIN, an ongoing 70-year old longitudinal study that has obtained menstrual calendar data of women throughout their reproductive life course. An additional complexity arises from the fact that these calendars have substantial missingness due to hormone use, surgery, failure to report, and loss of contact. We integrate multiple imputation and time-to event modeling in our Bayesian estimation procedure to deal with different forms of the missingness. Posterior predictive model checks are applied to evaluate the model fit. Our method successfully modeled patterns of women’s menstrual cycle trajectories throughout their late reproductive life and identified the change points for mean and variability of segment length, which provides insight into the menopausal process. More generally, our model points the way toward increasing use of joint mean-variance models to predict health outcomes and better understand disease processes

    A Varying-Coefficient Cox Model for the Effect of Age at a Marker Event on Age at Menopause

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    . It is of recent interest in reproductive health research to investigate the validity of a marker event for the onset of menopausal transition and to estimate age at menopause using age at the marker event. We propose a varying coefficient Cox model to investigate the association between age at a marker event, denned as a specific bleeding pattern change, and age at menopause, where both events are subject to censoring and their association varies with age at the marker event. Estimation proceeds using the regression spline method. The proposed method is applied to the Tremin Trust Data to evaluate the association between age at onset of the 60-day menstrual cycle and age at menopause. The performance of the proposed method is evaluated using a simulation study

    Piecewise Constant Cross-Ratio Estimation for Association in Bivariate Survival Data with Application to Studying Markers of Menopausal Transition

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    A question of significant interest in female reproductive aging is to identify bleeding criteria for the menopausal transition. Although various bleeding criteria, or markers, have been proposed for the menopausal transition, their validity has not been adequately examined. The Tremin Trust data are collected from a long-term cohort study that followed a group of women throughout their whole reproductive life, and provide a unique opportunity for assessing the association between age at onset of a bleeding marker and age onset of menopause. Formal statistical analysis of this dependence is challenging give the fact that both the marker event and menopause are subject to right censoring and their association depends on age at the marker event. We propose using cross-ratio to measure their dependence, which is assumed to be a piecewise constant function of age at onset of the marker event. Two estimation procedures using direct two-stage method and sequential two-stage method are proposed, while the latter is extended to allow for covariates in marginal survival functions. The proposed methods are applied to the analysis of the Tremin Trust data, and their performance is evaluated using simulations

    Genetic Differences May Reflect Differences in Susceptibility to Vulvodynia in General or in Spontaneous Remission Propensity

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    Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/110555/1/jsm12775.pd

    Remission, Relapse, and Persistence of Vulvodynia: A Longitudinal Population-Based Study

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    Background: Vulvodynia has been considered to be a chronic disorder. We sought to estimate the probability of and risk factors for remission, relapse, and persistence among women screening positive for vulvodynia. Methods: Survey-based assessment in a longitudinal population-based study of women (the Woman to Woman Health Study) who screened positive for vulvodynia and completed at least four follow-up surveys. Outcome measures included remission without relapse, relapse (after remission), and persistence of a positive vulvodynia screen. Multinomial regression was used to assess factors associated with outcomes. Results: Of 441 women screening positive for vulvodynia during the study, 239 completed 4 additional surveys. Of these, 23 (9.6%) had consistently positive vulvodynia screens, 121 (50.6%) remitted without relapse, and 95 (39.7%) relapsed following remission. Overall, factors associated with both relapse and persistence (compared with remission alone) included increased severity of pain ever (p?Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/140139/1/jwh.2015.5397.pd

    Lack of food access and food consumption patterns of late midlife women in southeast Michigan

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    Background: Food access is a key social determinant of health for older adults at high risk of chronic disease and physical disability. Methods: This cross-sectional analysis examined correlates of food access and the relationship between food access and food consumption characteristics in a sample of 316 late midlife women from Southeast Michigan in 2015-2016. Results: Lack of food access, defined as access to self-perceived adequate grocery shopping resources in one’s neighborhood, was reported by 20.9% of women. Women who reported lack of food access were less likely to report making meals at home (p=0.02) and had less frequent consumption of fresh fruits (p=0.04), fresh vegetables (p=0.001), and lean meats (p=0.048) as compared to those that did not report a lack of food access (p=0.04, p=0.001, p=0.048). Being African American (OR: 2.49; 95% CI: 1.20-5.17) and experiencing economic stress (OR: 2.86; 95% CI: 2.53-5.33) were major correlates of reporting lack of food access. Conclusion: Interventions to improve food access for midlife women may help address differences in chronic disease risk associated with diet quality among racial/ethnic groups and across socioeconomic status

    Changing Patterns of lung, liver, and head and neck non-AIDS-defining cancers relative to HIV status in Tanzania between 2002-2014

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    Abstract Background Tanzania, like other low-income countries, has an increasing cancer burden that remains underestimated. Infection-associated malignancies, particularly HIV-infection, represent a great proportion of cancer burden in Tanzania and throughout Africa. Availability of HIV treatment and improved survival of HIV patients are suggested factors related to increasing prevalence of non-AIDS-defining cancers (NADCs). This study examined patterns of NADCs and proportions of HIV-positivity at the Ocean Road Cancer Institute (ORCI). Methods We reviewed logbooks of all ORCI patients diagnosed and/or treated for lung, liver, and head and neck cancers during 2002–2014. The number of total cancers diagnosed at ORCI during this period was used to calculate proportions of NADCs. We abstracted medical records to obtain demographic and clinical profiles and HIV status information for 1127 patients diagnosed or treated during 2010–2014. Trends in numbers and proportions of NADCs were analyzed using Joinpoint regression. Characteristics of NADC patients were analyzed using multinomial logistic regression. Results NADCs diagnosed at ORCI increased by 33.8% from 2002 to 2014 while the proportion of NADCs relative to all cancers significantly decreased from 6.8% in 2002 to 5.6% in 2014 (APC = -2.74%). Numbers and proportions of lung and liver cancers increased compared to all cancer diagnoses from 2002 to 2014. The number of head and neck cancers increased while decreasing proportionally compared to all cancer diagnoses from 2002 to 2014. Among patients with pathologically confirmed NADCs between 2010 and 2014, HIV prevalence showed a non-statistically significant decrease from 8.1 to 7.1% (APC = -3.77%). Conclusions Absolute numbers of lung, liver, and head and neck cancers increased at ORCI by 1/3 since 2002. Improving survivorship of HIV patients and varying immunodeficiency status may have contributed to the increasing number of NADCs. Total cancer diagnoses nearly doubled during this period, leading to a smaller relative proportion of NADCs diagnosed in 2014 compared to 2002. Late- stage diagnosis and short survival of NADCs included this study may explain possible underestimation and smaller increase in proportion of these particular NADCs compared to other NADCs studied in Tanzania. The slight decrease in proportion of HIV-positive NADC patients during 2010–2014 may suggest increasing patient longevity and more effective HIV management in Tanzania.http://deepblue.lib.umich.edu/bitstream/2027.42/134744/1/13027_2016_Article_106.pd

    Multimodal Vulvar and Peripheral Sensitivity Among Women With Vulvodynia: A Case–Control Study

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    OBJECTIVE: To assess differences in vulvar and peripheral sensitivity between women with and without vulvodynia. METHODS: Women with vulvodynia (n = 41) and age-matched controls (n = 43) seen in the outpatient setting were evaluated via surveys, clinical examination, and multimodal sensory testing (pressure, heat, cold, vibration, and electrical stimulation). The relationships between sensitivity to various sensory modalities and case/control status, as well as by vulvodynia subgroups, were assessed using logistic regression. RESULTS: Women with vulvodynia were more sensitive to pressure and to electrical stimuli than were control women at the vulva (median, 22 vs 230 g and 0.495 vs 0.769 mA, respectively; P 0.025). Those reporting spontaneous pain versus provoked pain had greater pressure sensitivity to the thumb (median, 1850 vs 2690 g; P = 0.020) and greater electrical sensitivity at the introitus (0.450 vs 0.608 mA; P = 0.011), and those with primary versus secondary vulvodynia had substantially greater pressure sensitivity to the thumb (median, 2438 vs 3125 g, P = 0.004). However, having localized versus generalized vulvodynia was not associated with differences in pressure or electrical sensitivity. CONCLUSIONS: Sensitivities to pressure and electrical stimuli are greater among vulvodynia cases than among controls and support 2 previously defined subgroups-those reporting spontaneous pain versus those whose pain only occurred when provoked, and those with primary versus secondary vulvodynia

    Urogenital Symptoms and Pain History as Precursors of Vulvodynia: A Longitudinal Study

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    Abstract Background: We sought to assess vulvodynia incidence and risk factors among those with and without premorbid urogenital symptoms. Methods: Women's Health Registry members who completed a baseline assessment in 2004 were sent a 2-year and 4-year follow-up survey containing a validated screen for vulvodynia. Subgroup analysis of vulvodynia incidence rates was performed, and risk factors associated with incidence were assessed. Results: Of 1037 original enrollees, 723 (69.7%) completed consecutive surveys (initial and 2-year or initial, 2-year, and 4-year), 660 of whom did not have current or past vulvodynia at baseline. Of these 660, 71 (10.8%) first met criteria for vulvodynia within the 4-year period, for an annual incidence rate of 3.1% (95% confidence interval [CI] 2.5-4.0). Baseline strict controls were less likely to develop criteria for vulvodynia diagnosis (annual incidence rate of 1.4%) compared to those with an intermediate phenotype (presence of dyspareunia or history of short-term vulvar pain), for whom the incidence rate was 5.6% (p<0.001). Risk factors for incident vulvodynia differed between these two groups. Among the strict controls, an increased risk was noted among younger women (incidence rate ratio) [IRR] 3.6). For those with an intermediate phenotype, risk was increased among nonwhite women and those reporting pain with or after intercourse (IRR 2.2, 3.4, and 3.1, respectively). In both control groups, incident vulvodynia risk increased among those reporting urinary burning at enrollment (IRR 4.2 and 2.8 for strict and intermediate phenotype controls, respectively). Conclusions: The annual incidence of vulvodynia is substantial (3.1%) and is greater among women reporting a history of dyspareunia or vulvar pain that did not meet criteria for vulvodynia compared to those without this history, suggesting that generalized urogenital sensitivity may be a common underlying mechanism predating the clinical presentation of vulvodynia.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/98465/1/jwh%2E2012%2E3566.pd
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