An uncertain future for woodland caribou (Rangifer tarandus caribou): The impact of climate change on winter distribution in Ontario

Habitat alteration and climate change are two important environmental stressors posing increasing threats to woodland caribou, Rangifer tarandus caribou, in Ontario. Our first objective was to identify the importance of linear features, habitat, and climate on the occurrence of woodland caribou during the winter season using over 30 years of records (1980-2012). Our second objective was to forecast the impacts of climate change on the future occurrence and range of woodland caribou. Woodland caribou occurrence and environmental data collected during 1980 to 2012 were obtained from the Ontario Ministry of Natural Resources (OMNR). Logistic regression models were used to identify the importance of linear features, habitat, and climate on woodland caribou. We then forecast future caribou occurrences using 126 future climate projections. Woodland caribou preferred coniferous forests and mixed forests that tended to be associated with increased lichen coverage, and regions with colder winters. Woodland caribou also avoided anthropogenically disturbed regions, such as areas associated with high road density or developed areas. Caribou range extent was projected to contract by 57.2-100% by 2050 and 58.9-100% by 2070. Furthermore, all 126 climate change scenarios forecast a range loss of at least 55% for woodland caribou in Ontario by 2050. We project complete loss of woodland caribou in Ontario if winter temperatures increase by more than 5.6°C by 2070. We found that woodland caribou in Ontario are sensitive to changes in climate and forecasted that an average of 95% of Ontario’s native wood­land caribou could become extirpated by 2070. The greatest extirpations were projected to occur in the northernmost regions of Ontario as well as northeastern Ontario, while regions in western Ontario were projected to have the lowest rates of extirpation. This underscores the importance of mitigating greenhouse gases as a means to protect this iconic species

The impact of adversities across the lifespan on psychological symptom profiles in late adulthood: A latent profile analysis

People commonly face adverse circumstances throughout life, which increases risk for psychiatric disorders, such as anxiety, depression, psychosis, and posttraumatic stress disorder (PTSD). Adversities may occur during different periods in life. Especially adversity during early periods has been suggested to put individuals at risk for adverse mental health outcomes. Here, we investigated whether timing of adversity during the prenatal period, childhood, or mid-to-late adulthood differentially impacted classification into late adulthood symptom profiles. We performed sex-stratified Latent Profile Analysis to identify latent profiles regarding anxious, depressive, psychotic, and PTSD symptoms in n = 568 Dutch famine birth cohort members (n = 294 women, n = 274 men, mean age(SD) = 72.9(0.8)). Cross-sectional late adulthood symptomatology, childhood traumatic maltreatment, and adulthood trauma were based on self-report questionnaires. Prenatal adversity was considered present when individuals were prenatally exposed to the 1944-45 Dutch famine. In both men and women we identified one anxious/depressive profile and three profiles with approximately equal severity of all symptom types within each profile, yet differentiating in overall severity (low, mild, high) between profiles. We additionally found a PTSD symptom profile in women. In men, logistic regression models showed significant associations between prenatal, childhood and adulthood adversity, and profile classification, with differential effects depending on timing and most profound effects of child maltreatment. In women, childhood and adulthood adversity significantly increased classification probability into almost all profiles, with no significant effect of prenatal adversity. These findings support a time-dependent and sex-specific impact of adversity during different periods across the lifespan on psychological health, with consequences into late adulthood

Effects of prenatal exposure to the 1944–45 Dutch famine and glucocorticoid receptor polymorphisms on later life PTSD susceptibility

Background: Exposure to adversity in utero is thought to increase susceptibility to develop posttraumatic stress disorder (PTSD) following later life trauma, due to neurobiological programming effects during critical developmental periods. It remains unknown whether effects of prenatal adversity on PTSD susceptibility are modulated by genetic variations in neurobiological pathways implicated in PTSD susceptibility. Objective: We investigated whether genetic variation in the glucocorticoid receptor (GR) modulated effects of prenatal famine exposure on late adulthood PTSD symptom severity after trauma exposure in childhood and mid-to-late adulthood. Method: We included N = 439 term-born singleton adults (mean age: 72 years, 54.2% women) from the Dutch Famine Birth Cohort, born around the time of the Dutch Famine of 1944/1945, divided into exposure and control groups based on timing of the famine during gestation. Participants filled out self-report questionnaires on childhood (Childhood Trauma Questionnaire) and mid-to-late adulthood (Life Events Checklist for DSM-5) trauma, and current PTSD symptom severity (PTSD Checklist for DSM-5). GR haplotypes were determined from four functional GR single nucleotide polymorphisms (ER22/23EK, N363S, BclI and exon 9β) in previously collected DNA. Linear regression analyses were performed to investigate associations of GR haplotype and prenatal famine exposure in conjunction with later life trauma on PTSD symptom severity. Results: We observed a significant three-way interaction between the GR Bcll haplotype, famine exposure during early gestation, and adulthood trauma exposure on PTSD symptom severity in late adulthood. Only participants exposed to famine during early gestation without the GR Bcll haplotype showed a significantly stronger positive association between adulthood trauma and PTSD symptom severity than non-exposed participants, indicating increased PTSD susceptibility. Conclusions: Our results illustrate the importance of integrated approaches considering genetics and environmental contexts throughout various life periods, including the rarely investigated prenatal environment, to elucidate how PTSD susceptibility evolves throughout life. HIGHLIGHTS Adversity during pregnancy is thought to increase offspring's PTSD risk following later life trauma, but exact neurobiological mechanisms underlying this process remain unknown.We found that effects of prenatal famine exposure on PTSD symptom severity were influenced by genetic variation in the glucocorticoid receptor, which signals effects of the stress hormone cortisol. Integrated approaches considering genetics and environmental contexts throughout both early and later life are important to understand how PTSD risk evolves throughout life

The relationship between tonic immobility and the development, severity, and course of posttraumatic stress disorder: Systematic and meta-analytic literature review

Background: Tonic immobility (TI) is a reflexive, involuntary response that causes motor inhibition, vocal suppression, and analgesia. TI is elicited by extreme fear and perception of entrapment in a life-threatening situation. Research suggests that TI is a frequent peritraumatic response and may be related to subsequent posttraumatic stress disorder (PTSD). However, findings are mixed and, as of yet, no systematic or meta-analytic review examining associations between TI and PTSD has been published. Objective: We systematically and meta-analytically reviewed the literature and investigated whether TI is associated with the development, severity, and course of PTSD. Additionally, we evaluated whether different types of traumatic events are differentially associated with TI, and whether TI severity differs according to sex. Methods: A systematic literature search was conducted using Embase, PubMed, PsycINFO, and Scopus. Meta-analyses were performed on the included articles. Results: We identified 27 eligible articles. We found a significant association between TI and PTSD symptom severity (r = 0.39, 95% CI: 0.34–0.44; p <.0001). TI was more severe among females (Cohen's d=0.37, 95% CI: 0.25–0.48; p <.0001) and was more often elicited in situations involving interpersonal violence. We found limited longitudinal data to perform a meta-analysis of the association between TI and the development and/or course of PTSD. However, the literature available seems to support the role of TI in both the development and course of PTSD. Conclusions: Peritraumatic TI is associated with PTSD symptom severity, occurs more often during interpersonal violence, and is more severe among females. More longitudinal research is needed to investigate the role of TI in psychopathology development and course