Prevalence of pain and fear as barriers to vaccination in children – Systematic review and meta-analysis

BackgroundInjection-related pain and fear are common adverse reactions in children undergoing vaccination and influence vaccine acceptance. Despite the large body of literature on sources of vaccine non-compliance, there is no estimate of the prevalence of pain and fear as contributing factors. The objective was to estimate the prevalence of injection pain or fear of needles as barriers to childhood (i.e., 0–18 years) vaccination.MethodsFour databases were searched from inception for relevant English and French articles until August 2021. In addition, the references of recent systematic reviews and all articles included in the review were hand searched. Article screening and data extractions were performed in duplicate. Studies were included if they reported on injection-related pain or fear of needles in children (0–18 years) using a checklist/closed-ended question(s). Results were stratified by respondent (parents or children), type of pediatric population (general or under-vaccinated), and relative importance of barrier (pain or needle fear as primary reason or any reason for under-vaccination). Prevalence rates of pain or needle fear were combined using a random effects model. Quality of included studies was assessed using the Joanna Briggs Institute critical appraisal checklist for prevalence data. Quality across studies was assessed using GRADE.ResultsThere were 26 studies with 45 prevalence estimates published between 1995 and 2021. For parent reports (of children) and children self-reported reasons for non-compliance, prevalence rates of pain or needle fear ranged from 5 to 13% in a general population and 8 to 28% in an under-vaccinated population, with a substantial variation in the prevalence estimates. There was no difference between category of respondent or relative importance on pain or needle fear prevalence rate. A regression model demonstrated an overall prevalence rate of pain or needle fear as an obstacle to vaccination of 8% in the general population and 18.3% in the under-vaccinated population. All evidence was very low in quality.ConclusionThis is the first review to systematically quantify the prevalence and therefore, importance, of pain and needle fear as obstacles to vaccination in children around the world. Pain from injection or fear of needles were demonstrated to be sufficiently prevalent as barriers to vaccination in children to warrant attention. Addressing pain and fear has the potential to significantly improve vaccination acceptance.     

Spontaneous recovery of fear differs among early – late adolescent and adult male mice

Adolescence is a vulnerable period for developing anxiety-related mental disorders such as post-traumatic stress disorder (PTSD), which requires a long-term course of therapy when a traumatic event has been experienced during childhood. However, the biological mechanism underlying these age-dependent characteristics remains unclear. In the present study, we used early adolescent, late adolescent and adult (4-, 8-, and 15-week old) male mice to examine age differences in fear memory, fear extinction, and spontaneous recovery of fear. We also measured the activation of extracellular signal-regulated kinase (ERK) 2 in the dorsal hippocampus (dHip) and the basolateral amygdala (BLA) following a spontaneous recovery test. Our major findings were as follows: (1) early adolescent and adult mice did not recover the fear response; only late adolescent mice recovered the fear response. (2) The ERK2 in the dHip was more activated after the spontaneous recovery test in late adolescent mice than in adult mice, and the ERK2 in the BLA was more activated after the spontaneous recovery test in adult mice than in late adolescent mice. These results suggest that there exists a unique period in which spontaneous recovery occurs and that these late adolescent behavioral signatures may be related to alteration in the ERK2 phosphorylation in the dHip and BLA.     

前置胎盘孕妇恐惧心理观察及护理

目的观察前置胎盘孕妇的恐惧心理反应，做好前置胎盘孕妇的心理护理。方法由孕妇自行填写CES-D和SA2量表，进行统计学分析。结果70．2％的前置胎盘孕妇具有恐惧心理。结论在妊娠过程应提高孕妇认知水平，加强心理护理，有助于她们顺利渡过妊娠期。     

Sex effects in defensive behavior: Baseline differences and drug interactions

Female rats consistently show a pattern of differences in defensive behaviors compared to males which parallel the effects of exposure to a nonpainful threat stimulus (cat or cat odor) in the same tests and measures. These indications of greater defensiveness for females are particularly common in situations involving potential, as opposed to actual and present, threat, a factor which probably also reflects ceiling or floor effects in situations involving very intense defensiveness. In addition, pharmacological studies indicate sex differences in the effects of selective serotonin (5-HT) receptor agonists and antagonists on defensive responding. These findings indicate that sex effects must be considered in studies of the pharmacological control of defensive behaviors, and suggest that responsivity to sex effects may be an additional criterion for the suitability of animal models of anxiety.     

Fear and the startle reflex: Blink modulation and autonomic response patterns in animal and mutilation fearful subjects

The present study was designed to examine the pattern of startle reflex modulation and autonomic responses for individuals high in animal or blood-injury fear when viewing pictures of their feared objects. Sixteen individuals in each fear group and 16 low-fear control individuals viewed 32 color slides depicting fear-relevant, unpleasant but fear-unrelated, neutral, and pleasant scenes. Free viewing times were assessed in a second phase of the procedure as an index of avoidance behavior. Exposure to pictures of feared objects resulted in a consistent startle reflex potentiation and behavioral avoidance in both fear groups. This activation of the basic aversive system was independent of the autonomic pattern of the fear responses, which differed for the high-fear groups. These results suggest that the probe startle response indexes the organism's basic motivational disposition and add new information to the assessment of fear.     

Evidence for differential effects of 8-OH-DPAT on male and female rats in the Anxiety/Defense Test Battery

The Proxemics/Activity test and the Eat/Drink test, two components of the Anxiety/Defense Test Battery, were developed to measure defensive reactions to situations associated with a natural predator (cat). In the present studies the behavioral effects of 8-OH-DPAT treatment (0.01–1.0 mg/kg, SC) were entirely consistent with anxiety/fear reduction. These effects included an increase in time spent near the cat compartment, and a complimentary decrease in time spent farthest from this compartment, together with an increase in transits and locomote behavior. 8-OH-DPAT (1.0 mg/kg) also increased eat frequencies and durations (highly preferred food) both during and following cat presentation, without influencing drinking. This finding is discussed with reference to previous findings with 8-OH-DPAT in studies assessing both food intake and anxiolysis. Interestingly, 8-OH-DPAT was more potent in a majority of its effects in female subjects, a finding consistent with recent neurochemical data. These findings provide important behavioral evidence for a sexual differentiation in 5-HT function, and support the case for greater emphasis on female subjects in animal models of anxiety.Supported by NIH MH42803 and RCMI Grants RR03061 and RR01825     

Corticosterone controls the developmental emergence of fear and amygdala function to predator odors in infant rat pups

In many altricial species, fear responses such as freezing do not emerge until sometime later in development. In infant rats, fear to natural predator odors emerges around postnatal day (PN) 10 when infant rats begin walking. The behavioral emergence of fear is correlated with two physiological events: functional emergence of the amygdala and increasing corticosterone (CORT) levels. Here, we hypothesize that increasing corticosterone levels influence amygdala activity to permit the emergence of fear expression. We assessed the relationship between fear expression (immobility similar to freezing), amygdala function (c-fos) and the level of corticosterone in pups in response to presentation of novel male odor (predator), littermate odor and no odor. CORT levels were increased in PN8 pups (no fear, normally low CORT) by exogenous CORT (3 mg/kg) and decreased in PN12 pups (express fear, CORT levels higher) through adrenalectomy and CORT replacement. Results showed that PN8 expression of fear to a predator odor and basolateral/lateral amygdala activity could be prematurely evoked with exogenous CORT, while adrenalectomy in PN12 pups prevented both fear expression and amygdala activation. These results suggest that low neonatal CORT level serves to protect pups from responding to fear inducing stimuli and attenuate amygdala activation. This suggests that alteration of the neonatal CORT system by environmental insults such as alcohol, stress and illegal drugs, may also alter the neonatal fear system and its underlying neural control.     

Effects of stress and shock anticipation on prepulse inhibition of the startle reflex

The effects of shock anticipation and attention to external stimuli on prepulse inhibition (PPI) were compared. In the threat-of-shock experiment, acoustic startle stimuli were presented with and without prepulses when aversive shocks were or were not anticipated. In the control experiment, startle and prepulse stimuli were delivered during periods with attended or ignored external stimuli. In the threat-of-shock experiment, startle was potentiated (fear-potentiated startle) and PPI was increased by shock anticipation. A gradual reduction in the overall PPI throughout the experiment was also found. In the control experiment, only PPI was increased in the attend condition. The PPI level remained constant throughout the experiment. The increase in PPI in the threat and attend conditions may have resulted from an increase in the general level of alertness that facilitated the processing of the prepulse. The gradual decrease in PPI in the threat experiment was hypothesized to result from a progressive deficit in sensory functioning due to the stressful nature of repeated shock anticipation.     

Anxiolytic effects of buspirone and gepirone in the fear-potentiated startle paradigm

Fear potentiation of the acoustic startle reflex was produced by eliciting startle responses in the presence of a light that had been previously paired with a shock. Buspirone (0.6–5.0 mg/kg) and gepirone (1.25–10.0 mg/kg), but not their common metabolite, 1-PP (0.5–40 mg/kg), produced a dose-dependent reduction of fear-potentiated startle. These doses of buspirone and gepirone slightly increased baseline startle levels. Reduction of fear-potentiated startle appears to involve supraspinal sites of action, since intraventricular but not intrathecal administration of buspirone (200 ;g) reduced fear-enhanced startle. Both buspirone and gepirone were highly efficacious in this model compared to other animal tests that are used to study anxiolytic compounds.     

306名大学生错失恐惧与社交媒体倦怠的关系:睡眠质量和负性情绪的链式中介作用

目的 探讨大学生睡眠质量、负性情绪在错失恐惧与社交媒体倦怠间的中介作用。 方法 采用错失恐惧量表、社交媒体倦怠量表、匹兹堡睡眠质量指数量表、抑郁-焦虑-压力量表简体中文版对306名大学生进行调查。 结果 错失恐惧、社交媒体倦怠、睡眠质量和负性情绪之间呈两两正相关;错失恐惧能正向预测社交媒体倦怠;睡眠质量和负性情绪在错失恐惧和社交媒体倦怠之间起单独中介作用,且睡眠质量和负性情绪在错失恐惧与社交媒体倦怠之间起链式中介作用,负性情绪各维度效应皆成立。 结论 睡眠质量和负性情绪能够为错失恐惧对社交媒体倦怠的影响提供一个解释机制,大学生的错失恐惧既可以直接影响其社交媒体倦怠水平,也可以通过睡眠质量、负性情绪的独立中介效应以及睡眠质量-负性情绪的链式中介效应间接影响。