Extinction of populations due to inbreeding depression with demographic disturbances

The process of population extinction due to inbreeding depression with constant demographic disturbances every generation is analysed using a population genetic and demographic model. The demographic disturbances introduced into the model represent loss of population size that is induced by any kind of human activities, e.g. through hunting and destruction of habitats. The genetic heterozygosity among recessive deleterious genes and the population size are assumed to be in equilibrium before the demographic disturbances start. The effects of deleterious mutations are represented by decreases in the growth rate and carrying capacity of a population. Numerical simulations indicate rapid extinction due to synergistic interaction between inbreeding depression and declining population size for realistic ranges of per-locus mutation rate, equilibrium population size, intrinsic rate of population growth, and strength of demographic disturbances. Large populations at equilibrium are more liable to extinction when disturbed due to inbreeding depression than small populations. This is a consequence of the fact that large populations maintain more recessive deleterious mutations than small populations. The rapid extinction predicted in the present study indicates the importance of the demographic history of a population in relation to extinction due to inbreeding depression.     

Ergodicity and extinction in a stochastic susceptible-infected-recovered-susceptible epidemic model with influence of information

An epidemic model with stochastic contact transmission coefficient takes into account white noise and the influence of information. Sufficient conditions for the extinction and persistence of the disease are expressed. The existence of a stationary distribution and the ergodic property are proved. The peak of infected population can be decreased by information. The analytical results are showed by simulations and the influence of white noise and information on the dynamics of epidemics are evaluated.     

Qualitative insights into women's personal experiences of perinatal depression and anxiety

Background and aimSymptoms of perinatal depression and anxiety are usually described and understood from a nosological perspective. This research sought to gain insight into women's lived experience of postnatal depression and anxiety, the factors that contribute to these symptoms and the context in which they develop.MethodFace to face and telephone interviews were conducted with 28 women from metropolitan and rural areas across Australia, who had experienced postnatal depression and/or anxiety within the last five years. Analysis was conducted from a grounded theory perspective.FindingsParticular symptoms of anxiety and depression develop in the context of the numerous changes inherent to the transition to motherhood and contribute to a common experience of frustration and loss. Symptoms were also associated with feelings of dissatisfaction with the pregnancy and motherhood experience.ConclusionsThe findings provide useful insights into women's experiences of mental health symptoms during the perinatal period, how these symptoms present and the factors involved in their development and maintenance. The need to consider women's perspectives to develop resources and health promotions strategies, as well as within the context of relationships with health professionals is highlighted. The study emphasizes the need for greater, more accurate information surrounding perinatal depression and the need to increase the profile and awareness of anxiety disorders.     

Predictors of postpartum depression service use: A theory-informed,integrative systematic review

ProblemPostpartum depression affects many women globally, yet rates of treatment use are low. A comprehensive view of factors associated with treatment use, from women’s and providers’ perspectives, based on a theoretical model is lacking.BackgroundSeveral studies examined various factors associated with postpartum depression service use; however, each study focused on a small number of factors.AimThis study describes a systematic literature review based on the Behavioral Model of Health Service Use. The purpose of this article is to review and synthesize the available literature regarding factors associated with women’s mental health service use for postpartum depression from women’s and healthcare providers’ perspectives, and provide a comprehensive integrative view of the subject.MethodsThree electronic databases were searched, and 35 studies published up to 2018 in English language journals met inclusion criteria for review. Factors associated with postpartum depression service use were classified according to the Behavioral Model of Health Service Use’s constructs.FindingsService use for postpartum depression is a function of a woman’s predisposition to use mental health services; individual, familial, and communal factors which enable or pose barriers to use of mental health services; and the woman’s perceived or evaluated need for treatment. In addition, societal determinants impact the woman’s decision to seek help directly or through impacting the health and mental health care service system’s resources and organization.ConclusionThis review illustrates key factors for researchers and practitioners to consider when treating postpartum women and developing interventions to enhance postpartum depression treatment use.     

A longitudinal study of perinatal depression among Chinese high-risk pregnant women

Background

Information is needed on the prevalence of depression in Chinese women with medically defined complications across the perinatal period, as well as key risk factors to develop appropriate perinatal mental health services and ensure the services target those most in need.

The effect of antenatal screening for depression on neonatal birthweight and gestation

BackgroundAntenatal depression has been associated with poor perinatal outcomes such as preterm birth and low birth weight. Universal screening of perinatal depression has been recommended to improve maternal and pregnancy outcomes.Hypothesis and aimWe hypothesise that screening for antenatal depressive symptoms may reduce the risk of preterm birth and low birth weight. To assess the hypothesis, we explore the association between antenatal depression screening using the Edinburgh Postnatal Depression Scale and neonatal outcomes.MethodsA retrospective analysis of state-wide population-based health administrative data. Inclusion criteria were pregnant women who gave birth to a singleton in Queensland in the second half of 2015 (29,543 women). Logistic regression analyses were run in 27,817 women with information in all variables. Main outcomes were preterm birth (<37 weeks of gestation) and low birth weight (<2500 grs).ResultsWomen who did not complete the screening had increased odds of preterm birth (AOR, 1.56; 95% CI, 1.39–1.74; p < 0.001) and low birth weight (AOR, 1.48; 95% CI, 1.30–1.68; p < 0.001) before and after adjustments for relevant confounders when compared to women who completed the screening. Sensitivity analyses performed in women with spontaneous labour and in women without a diagnosis of depression showed similar results.Conclusion(s)We found an association between screening for depressive symptoms during pregnancy and better neonatal outcomes. However, this result does not necessarily infer causality. Any association may represent a previously unknown benefit to screening, which could support the case for universal antenatal depression screening.     

The effects of ego-resilience,social support,and depression on suicidal ideation among the elderly in South Korea

South Korea’s elderly suicide rate is not merely the highest among the member nations of the Organization for Economic Cooperation and Development, it is the highest in the world. This study analyzed the effect of ego-resilience and social support on depression and suicidal ideation of the elderly, providing baseline data to aid in the development of preventive programs on elder suicide. We found that ego-resilience is a strong inhibitor of suicidal ideation. Direct and indirect effects of social support on suicidal ideation were especially helpful for elders with mild depression.