Food allergy in adolescents: validation of the food allergy independent measure and the EuroPrevall food allergy quality of life questionnaire into Spanish

Background: Different questionnaires have been developed globally to assess and compare the impact of food allergy on the quality of life. The aim of this study was to validate a Spanish translation of the Food Allergy Independent Measure (FAIM) and the EuroPrevall Food Allergy–Quality of Life Questionnaire–Teenage Form (FAQLQ-TF) for adolescents aged 13–17 years. Methods: Sixty adolescents diagnosed with immunoglobulin E-mediated allergy to food completed the questionnaires. Cronbach’s alpha was used to assess internal consistency; correlation between FAQLQ-TF and FAIM was used to test construct validity. The discriminant validity was evaluated by comparison with the number of offending foods, the perceived impact on social life, the diagnosis of anaphylaxis, and the previous prescription of adrenaline auto--injectors (AAI). Results: No question fulfilled criteria to be removed from the questionnaire. For FAIM, Cronbach’s alpha = 0.763, and for the four domains of FAQLQ-TF, Cronbach’s alpha = 0.797–0.847. A significant correlation existed between FAQLQ-TF and FAIM, and of both of them with anaphylaxis and the prescription of AAI (P ˂ 0.05 for all comparisons). Conclusions: This Spanish translation of FAIM and FAQLQ-TF for adolescents had good internal consistency and construct validity as well as ability to discriminate patients according to the number of foods to avoid, impact on social life, diagnosis of anaphylaxis, and AAI prescription (AU)

Maternal stress and depression are associated with respiratory phenotypes in urban children.

BACKGROUND: Prenatal and early-life exposure to maternal stress and depression is linked to development of recurrent wheezing in young children. OBJECTIVE: We sought to determine whether maternal stress and depression in early life are associated with nonatopic wheezing phenotype in urban children. METHODS: The Urban Environment and Childhood Asthma Study examined a birth cohort of children at high risk for asthma in low-income neighborhoods. Prenatal and postnatal (through age 3 years) maternal stress and depression scores were compared with respiratory phenotypes through age 10 years (multinomial regression), self-reported colds (linear regression), and detection of respiratory viruses (Poisson regression). RESULTS: Scores for maternal depression, and, to a lesser extent, maternal perceived stress, were positively related to multiple wheezing phenotypes. In particular, cumulative measures of maternal depression in the first 3 years were related to the moderate-wheeze-low-atopy phenotype (odds ratio, 1.13; [1.05, 1.21]; P < .01). Considering indicators of respiratory health that were used to identify the phenotypes, there were multiple positive associations between early-life scores for maternal stress and depression and increased wheezing illnesses, but no consistent relationships with lung function and some inverse relationships with allergic sensitization. Cumulative maternal stress and depression scores were associated with cumulative number of respiratory illnesses through age 3 years. CONCLUSIONS: Among high-risk, urban children, maternal stress and depression in early life were positively associated with respiratory illnesses and a moderate-wheeze-low-atopy phenotype. These results suggest that treating stress and depression in expectant and new mothers could reduce viral respiratory illnesses and recurrent wheeze during the preschool years and some forms of childhood asthma.

Allergic diseases do not impair the cognitive development of children but do damage the mental health of their caregivers.

This study aimed to investigate whether children with atopic diseases exhibited different neurodevelopment function from healthy controls and whether their caregivers had differential parental stress. In total, we recruited 109 patients with atopic diseases (mean age 6.8 years, 54.1% male) and 82 healthy children (mean age 6.3 years, 54.9% male). Based on the children's age, they underwent developmental, cognitive evaluations and attention deficit/hyperactivity disorder (ADHD) symptoms. The parenting stress of children's caregivers was evaluated using the Chinese Health Questionnaire (CHQ-12) and Family APGAR. Of the children with atopic diseases, 87.2%, 74.3%, 29.4%, and 8.3% of them had allergic rhinitis, asthma, atopic dermatitis, and urticaria, respectively. None of these conditions were associated with children's cognitive profiles or ADHD symptoms. However, the caregivers of patients who had asthma suffered from higher CHQ-12 scores than those of patients without asthma. Furthermore, the number of atopic diseases had a dose-response effect on caregivers' CHQ-12 scores. In conclusion, allergic diseases did not impair the cognitive development of children. However, caregivers of patients with asthma or multiple atopic diseases may suffer a greater mental health burden with regard to caring for their children. Such caregivers may require support to effectively fulfill their parenting roles.

Biological Sex and IgE Sensitization Influence Severity of Depression and Cortisol Levels in Atopic Dermatitis.

BACKGROUND: Depression is a common comorbid condition with atopic dermatitis (AD), particularly during the active disease cycle. Controversial results regarding the contribution of biological sex, immunoglobulin E (IgE) sensitization, and cortisol on AD severity and comorbid depression justify further investigation. OBJECTIVE AND METHODS: To explore the influence of sex and IgE sensitization on biochemical and psychological parameters, and severity of AD, a case-control study of 105 volunteers (56 AD, 49 healthy controls (HC); 50 males, 55 females) was conducted over 10 weeks, starting at dermatological symptom onset. Disease severity, serum IgE, cortisol and testosterone levels, and depression scores were assessed at study baseline and after 10 weeks of conventional treatment. RESULTS: Dermatological severity differed among AD males by IgE sensitization and was elevated in males with extrinsic atopic dermatitis (EAD). Hamilton Depression Rating Scale (HAMD) scores were elevated in all patients at study baseline and improved with symptom reduction to HC levels, except female EAD. Severity of depression and dermatitis were correlated in EAD males at baseline and at week 10. Serum cortisol was elevated in male EAD at baseline, in contrast to males with intrinsic atopic dermatitis (IAD) at week 10. In addition, cortisol levels were found negatively correlated with SCORAD and HAMD scores in EAD males at week 10. CONCLUSION: Pathophysiological features of AD and depression are likely related to different inflammation-based effects and appear to be biological sex-dependent. Cortisol levels depend on biological sex and IgE sensitization in AD and increase in males with EAD at exacerbation and IAD males at resolution. Biological sex-related disease triggers, IgE sensitization, and cortisol levels are important for the understanding of the mechanisms underlying AD and comorbid depression.

Impact of allergies on health-related quality of life in patients with asthma.

Objective: To estimate the health-related quality of life (HRQoL) and health utilities among asthma patients with and without comorbid allergies in a managed care population.Methods: This was a retrospective analysis of patient survey responses and pharmacy claims from the Observational Study of Asthma Control and Outcomes (OSACO). Patients ≥12 years-old with persistent asthma received four identical surveys between April-2011 and December-2012. The presence of allergy was identified by a positive response to a survey question about hay fever/seasonal allergies and ≥1 diagnosis-related ICD-9-CM code(s) for allergic conditions. HRQoL instruments included generic utility (EQ-5D-3L [including VAS]), asthma-specific utility (AQL-5D) and asthma-specific health status (Mini Asthma Quality of Life Questionnaire [MiniAQLQ]). Median regression was used for utility scores and Least Squares regression for MiniAQLQ, adjusting for sociodemographic characteristics and smoking.Results: Of the 2681 asthmatics who completed the first survey in the OSACO study, 971 had comorbid allergies. After adjusting for covariates, asthma patients with comorbid allergies had significantly lower MiniAQLQ scores than patients without allergies (-0.489 [95% CI -0.570, -0.409]; p < 0.01), with the greatest decrement/impairment observed for the environmental stimuli domain (-0.729 [95% CI -0.844, -0.613]; p < 0.01). Utility scores were also statistically significantly lower for asthma patients with comorbid allergies compared to those without allergies (EQ-5D, -0.031 [95% CI -0.047, -0.015]; AQL-5D, -0.036 [95% CI -0.042, -0.029]; p < 0.01 each).Conclusions: The presence of allergies with persistent asthma is associated with a significant deleterious impact on several different measures of HRQoL.

Asthma, atopy and serious psychological distress: prevalence and risk factors among young people in the Melbourne atopy cohort study.

Background: While atopic conditions are associated with increased risk of mental health problems, the evidence that a range of allergic conditions are associated with psychological distress in young people is less clear.Methods: We recruited a longitudinal birth cohort study of 620 children with a family history of allergic disease. At the 18-year follow up, atopic sensitization was determined by skin prick testing. Surveys were used to determine psychological distress (Kessler 6), quality of life (SF12), respiratory symptoms and management, presence of current eczema and hay fever. Regression models were used to identify predictors of psychological distress and quality of life, while controlling for potential confounders.Results: Prevalence of serious psychological distress was quite low (n = 22, 5.3%), and there were no associations between psychological distress and current atopic sensitization, symptoms of hay fever, eczema or asthma. Smoking status and lower level of maternal education were associated with lower physical quality of life (SF12 PCS subscale). Psychological distress total score, lower maternal education, smoking, female sex, and current eczema were associated with worse mental quality of life (SF12 MCS subscale).Conclusion: We found relatively low levels of psychological distress in this cohort of young adults, despite a high prevalence of allergic diseases. Positive social factors may serve to buffer psychological distress amongst the cohort accounting for the low prevalence of serious psychological distress observed.

Validation of a Spanish version of the EuroPrevall Food Allergy Quality of Life Questionnaire-Parental Form

Background: Food allergy can have a major impact on quality of life of children and their parents. Questionnaires have been developed to measure the impact of this disorder. We aimed to validate the EuroPrevall questionnaire on Food Allergy-Quality of Life Questionnaire, Parent Form (FAQLQ-PF) and the Food Allergy Independent Measure (FAIM), translated into Spanish. Methods: The internal consistency of the FAQLQ-PF and the FAIM, translated into Spanish (Spain) and completed by the parents of 74 children with IgE-mediated food allergy, were evaluated with Cronbach's alpha. To test construct validity of the FAQLQ-PF, its correlation with the FAIM was also calculated. To assess their discriminant validity, we compared the values of both depending on the number of offending foods and for children with and without anaphylaxis. Results: The values of Cronbach's alpha for the three domains in the FAQLQ-PF were over 0.9. The value of alpha for FAIM questions was below 0.6, which was attributed to the wording of one question. When this question was removed, alpha increased to over 0.70. There was a significant correlation between the FAQLQ-PF score and the FAIM. There were significantly poorer FAQLQ-PF scores in children with more food allergies and worse FAIM in those who had had anaphylaxis. Conclusions: The Spanish version of the FAQLQ-PF had a good internal consistency, good construct validity and validity to discriminate patients with more food allergies and anaphylaxis. It can be used as a tool to evaluate and monitor the quality of life in families with food allergic children (AU)

No disponible

Maternal Stress During Pregnancy and Allergic Diseases in Children During the First Year of Life.

BACKGROUND: Many recent studies indicate that prenatal maternal distress increases the risk of allergic diseases in children. The mechanisms that favor it are still unclear. OBJECTIVES: We aimed to assess the association between exposure to different kinds of prenatal stress and the occurrence of atopic dermatitis, food allergy, wheezing, and recurrent respiratory tract infections in children. METHODS: The study population consisted of 370 mother-child pairs from a Polish Mother and Child Cohort (REPRO_PL). The analysis was restricted to the women who worked at least one month during the pregnancy period. Maternal psychological stress during pregnancy was assessed based on the Subjective Work Characteristics Questionnaire, the Perceived Stress Scale, and the Social Readjustment Rating Scale. The presence of atopic dermatitis, food allergy, wheezing, and recurrent respiratory tract infections in children was evaluated by doctors at 12 months of age. RESULTS: In a univariate model, we showed significant association between maternal life stress (according to the Perceived Stress Scale) and stressful life events (according to the Social Readjustment Rating Scale) and infant wheezing (at least 1 episode of wheezing during the first year of life). A multivariate model of logistic regression analysis revealed that maternal stress during pregnancy, described by the Social Readjustment Rating Scale, increased the risk of wheezing in children (OR 1.09, 95% CI 1.01-1.02) independently from other predictors of wheezing previously determined in this cohort, such as the number of infections and maternal smoking. We observed also significant positive association between maternal life stress during pregnancy measured by the Perceived Stress Scale and the risk of recurrent respiratory tract infections in the first year of life, however it was not significant after adjustment for confounding variables. CONCLUSIONS: Maternal stress during pregnancy increases the risk of childhood wheezing. The effects of stress during pregnancy on the onset of allergic diseases in children should be developed and translated into early prevention strategies.

Risk of suicide for individuals reporting asthma and atopy in young adulthood: findings from the Glasgow Alumni study.

There is emerging evidence that asthma and atopy may be associated with a higher risk of suicide. We investigated the association of asthma and atopy with mortality from suicide (n=32) in the Glasgow Alumni cohort, adjusting for the key confounders of socioeconomic position and smoking. We found no evidence of an association in our a priori atopy phenotypes with suicide, and there were insufficient suicides in the asthma phenotypes to draw any conclusions. In additional analyses, individuals reporting both eczema-urticaria and hay fever and those with family history of atopy were at higher risk of suicide. As these were secondary analyses and based on small numbers of events we cannot rule out chance findings. The lack of evidence in our main hypothesis may be due to the small number of suicides or reported associations between asthma and atopy may be confounded.

Association of Tourette syndrome and obsessive-compulsive disorder with allergic diseases in children and adolescents: a preliminary study.

OBJECTIVES: To investigate the rate of allergic diseases including asthma, allergic rhinitis and eczema in children and adolescents diagnosed with obsessive-compulsive disorder (OCD) (n:26) and/or Tourette syndrome (TS) (n:32) [OCD plus TS, n:13] compared to control subjects (n:35) [total, n:80]. PATIENTS AND METHODS: The symptoms of any allergic disease were assessed using the ISAAC questionnaire form. Allergy diagnoses were made by a pediatric allergy specialist. Skin prick tests were applied, and IgE levels and eosinophil counts were measured. RESULTS: While only one-fifth of the control subjects had allergic diseases, more than half of the children with TS and/or OCD had comorbid allergic diseases. Positive skin prick tests were greater in OCD patients compared to control subjects. There were no significant differences between the groups in terms of eosinophil counts or IgE levels. Among the allergic diseases, while allergic rhinitis was diagnosed at significantly higher rates in TS patients, eczema was significantly higher in OCD patients compared to control subjects. CONCLUSIONS: This preliminary study shows an association between allergic diseases and TS and/or OCD. The results revealing differences in associations between types of allergic disease (rhinitis or eczema) and neuropsychiatric disorder (tic disorder or OCD) need to be investigated in further studies with higher numbers of participants, and immune markers should be examined.

Parenting and relationship characteristics in mothers with their children having atopic disease.

This study compared parental cognitions and relationship characteristics of mothers of children with atopic disease with those of mothers of children without atopic disease. These factors include child-rearing attitudes, parental locus of control, parental sense of competence, attachment security, and maternal sensitivity. Preplanned subanalyses were carried out according to specific disease, mothers' perception of disease severity, and presence of concurrent atopic diseases. The descriptive comparative study of 233 Korean mothers included 102 mothers of children aged six years or younger with atopic dermatitis, asthma, and/or allergic rhinitis. Data were collected from 2007 to 2008 from local clinics and day care centers. Parental cognitions and relationship characteristics did not differ significantly between groups of mothers, except that mothers of children with atopic dermatitis showed less affection. However, subanalyses showed that mothers who perceived their child's disease to be severe were less likely to encourage autonomy and had a lower sense of competence, more rejecting attitudes, and an external locus of control. Although we should be cautious in generalizing these results, special care plans are strongly recommended for mothers of children with severe atopic disease to provide support and education, help mothers develop an internal locus of control, and increase parental sense of competence.

Childhood chronic physical condition, self-reported health, and life satisfaction in adolescence.

The present study investigates the prevalence and type of chronic conditions at 7 years of age-with special reference to atopic conditions-and their longitudinal associations with self-reported health and life satisfaction in adolescence. The data were obtained from Northern Finland Birth Cohort 1986 (NFBC 1986), which is a longitudinal 1-year birth cohort from an unselected, regionally defined population (n = 9,432). The present study investigated a sample of 8,036 children with data of chronic conditions at 7 years of age and a sample of 6,680 children with data of chronic conditions at 16 years of age. According to parents' report the prevalence of CC at 7 years of age was 14.8 % among boys and 13.2 % among girls, these figures being at 16 years of age 20.7 and 19.4 %, respectively. Atopic conditions were the most common chronic conditions at 7 years of age (12.7 % vs. other chronic conditions 4.7 %). Childhood chronic condition was associated with subsequent self-reported health in adolescence, but not with subsequent self-reported life satisfaction. Chronic condition at 7 years of age increased the risk of reporting health as "poor" even if the chronic condition was no longer prevalent at 16 years of age. Atopic conditions seemed to be linked with self-reported poor/moderate health more often than other chronic conditions among girls. Conclusion Childhood chronic conditions seem to affect adolescent's subjective health, but fortunately, they do not affect adolescents' subjective well-being to such an extent that it could lower their life satisfaction.

Stress and allergic diseases.

Allergy describes a constellation of clinical diseases that affect up to 30% of the world's population. It is characterized by production of allergen-specific IgE, which binds to mast cells and initiates a cascade of molecular and cellular events that affect the respiratory tract (rhinitis and asthma), skin (dermatitis, urticaria), and multiple systems (anaphylaxis) in response to a variety of allergens including pollens, mold spores, animal danders, insect stings, foods, and drugs. The underlying pathophysiology involves immunoregulatory dysfunctions similar to those noted in highly stressed populations. The relationships in terms of potential for intervention are discussed.

Effects of examination stress on psychological responses, sleep and allergic symptoms in atopic and non-atopic students.

BACKGROUND: Recent findings indicate that atopics may be more vulnerable to stress than non-atopics. However, the roles of psychological well-being and sleep in this presumed increased sensitivity are not known. PURPOSE: To investigate the effects of a brief naturalistic stressor on psychological responses, sleep, and allergic symptoms and to compare those responses between atopic and non-atopic individuals. METHODS: We assessed atopic and non-atopic students during a period without and during a period with examinations. RESULTS: For both atopic and non-atopic students, tension, anxiety, and depression deteriorated in response to examination, as did sleep latency and sleep quality. Overall, atopics were more tense, had more anxiety, longer sleep latencies, and were less well rested than non-atopics. Non-atopic students rose from bed later during the examination period. In response to examination, atopic students reported increased frequency of stress behaviors (e.g., eating fast), while decreased stress behaviors were reported by non-atopic students. Allergic symptoms were not affected. CONCLUSION: Atopic students were worse off in aspects of psychological well-being and sleep, but displayed only partly stronger responses to a stressor compared to non-atopic students. In spite of a broad negative response to examination, allergic symptoms were not affected.

The view of patients with asthma or chronic obstructive pulmonary disease (COPD) on complementary and alternative medicine.

BACKGROUND: The popularity of complementary and alternative medicine (CAM), particularly for chronic diseases such as asthma, is growing rapidly, but little is known about the characteristics of CAM use by patients with asthma and chronic obstructive pulmonary diseases (COPD). The aim of the present study is to compare the knowledge and preferences of patients with asthma or COPD about CAM, to evaluate the extent, characteristics and possible predictors of CAM use. METHODS: A face-to-face interview questionnaire was administered to the patients who attended the Allergic Diseases and Chest Diseases clinics between May 2005-January 2006, and 364 patients answered the questionnaire. RESULTS: 43.1 % (n = 90) of the 209 asthmatic patients, and 43.2 % (n = 67) of the 155 COPD patients had used some type of CAM previously. The asthmatic patients who have been admitted to the Emergency Room(ER) more frequently tend to use CAM methods (p = 0.03), whereas duration of doctor diagnosis, hospitalizations, admissions to ER and to be educated for diseases have a higher impact on CAM use in COPD patients (p = 0.00, p = 0.00, p = 0.00 and p = 0.04, respectively). The most commonly used forms of CAM were herbal medicines (57.8 % vs. 70.1 %) and quail egg (46.7 % vs. 37.3 %) in patients with asthma and COPD, respectively. The reported frequency of the subjective sense of improvement was higher in asthmatic patients than COPD patients but this difference was insignificant (50.0 % vs.39.4 %; p = 0.24). CONCLUSION: Most of the patients with asthma or COPD prefer alternative medicine. CAM use by patients with COPD should be asked about by their doctors, strongly advised about continuing their medicines and about side effects of CAM.

Personality characteristics in chronic and non-chronic allergic conditions.

In psycho-allergological research, the potential relevance of personality factors in the maintenance and exacerbation of atopic symptoms is still a matter of debate. The present study aimed to assess personality dimensions in chronic atopic disease, i.e. atopic dermatitis (AD) and in acute manifestation of atopy (seasonal allergic rhinitis, SAR). Further, the association of a potentially atopy-specific personality profile with atopy-relevant biological stress responses should be evaluated. Subjects suffering from AD (n=36), or SAR (n=20) and non-atopic controls (n=37) were investigated. To determine different personality domains, Spielberger's State-Trait Anxiety Inventory (STAI), the Questionnaire for Competence and Control (FKK) and the Questionnaire for Stress Vulnerability (MESA) were administered. To assess the relation between these personality dimensions and biological stress responses, atopics and non-atopic controls were exposed to a standardized laboratory stressor (Trier Social Stress Test, TSST). Endocrine (cortisol, ACTH), immune (total IgE, leukocyte subsets) and physiological (heart rates) measures were recorded before and after the stress test. When compared to healthy controls, AD and SAR patients showed significantly higher trait anxiety (STAI) and stress vulnerability in situations characterized by failure, job overload and social conflicts (MESA). Moreover, AD subjects scored significantly lower in self-competence and self-efficacy (FKK) as well as in recreation ability (MESA). No difference trait anxiety and stress vulnerability could be detected between AD and SAR subjects. Pearson correlational analyses yielded no significant correlation between the different personality domains and the endocrine, physiological and immunological stress responses. However, stress-induced increase in eosinophil number was significantly correlated with the perceived self-competence/self-efficacy in SAR patients.

Inhibitory effects of Moutan cortex on immediate allergic reactions.

The anti-allergic effect of an ethanol extract from Moutan Cortex was evaluated in some animal models. The Moutan Cortex extract (30, 100 mg/kg, i.p.) dose-dependently inhibited systemic anaphylactic shock induced by compound 48/80 in mice. It also inhibited dose-dependently the scratching behavior induced by compound 48/80 or histamine at a dose of 100 mg/kg. An increase in the vascular permeability induced by compound 48/80 or histamine was also inhibited by the Moutan Cortex. In addition, in vitro studies, the Moutan Cortex inhibited histamine release from rat peritoneal mast cells induced by compound 48/80. To investigate the active component of Moutan Cortex extract, it was suspended in water and extracted with EtOAc to yield EtOAc insoluble (A) and soluble (B) fractions. The effect of extract (B) was more potent than that of extract (A) in inhibiting histamine release. From these findings, it seems likely that the Moutan Cortex extract is effective in antagonizing certain pharmacological effects induced by compound 48/80, which is probably mediated by inhibiting the release of histamine from mast cells and antagonizing the effect on histamine. The main active component of Moutan Cortex is considered to be contained in extract (B). In conclusion, Moutan Cortex may be useful for the relief of symptoms of atopic dermatitis and other allergy-related diseases.

Anxiety in allergy and atopic dermatitis.

PURPOSE OF REVIEW: Individuals suffering from allergies often exhibit a specific psychological profile characterized by anxiety, depression and emotional excitability. Emotional stress precipitates allergic symptoms not only by heightening anxiety levels but also by dysregulating immune-cell functions. The primary objective of this report is to review recent findings of the relationship between anxiety and hypersensitivity responses in the context of psychoneuroimmunology in allergic individuals, notably patients with atopic dermatitis. RECENT FINDINGS: Atopic subjects with emotional problems develop a vicious cycle between anxiety and clinical symptoms. Acute stresses, which repeatedly and chronically affect patients with atopic dermatitis, raise anxiety in general more preferentially than anxiety at present. This psychological failure enhances Th2-type responses due to dysregulation of the neuroimmune system, leading to worsening of allergic symptoms. Tandospirone, a 5-hydroxytryptamine 1A receptor agonist with anxiolytic and antidepressant effects, attenuates itching through successful control of emotional difficulties. These data suggest the efficacy of administrating drugs with anxiolytic effects as part of the management strategy of stress-associated itching in patients with atopic dermatitis. SUMMARY: Psychological interventions such as periodic monitoring of anxiety levels in the context of immune functions and skin conditions are fundamental in therapy of allergic patients with emotional problems.

Cortisol circadian rhythms and stress responses in infants at risk of allergic disease.

BACKGROUND: The cortisol circadian rhythm and response to stressful stimuli are altered in children and adults with allergic disease, including asthma. It is not known whether these alterations precede or follow the onset of allergic disease. OBJECTIVE: We sought to evaluate the cortisol circadian rhythm and stress response among infants at risk for the development of allergic disease. METHODS: Infants with and without risk factors for allergic disease were evaluated at age 6 months. Saliva was obtained at 8 am, 2 pm, and 8 pm at home (n = 68) by parents when their infants were comfortable and in the clinic (n = 88) before and after their physical examination and vaccinations. Information regarding parental allergy and exposure to other children at home or in child care were obtained by questionnaire. RESULTS: In multivariate analysis the circadian rhythm of cortisol was flattened because of the lack of the expected morning surge of cortisol, resulting in decreased diurnal variation of cortisol in infants of mothers with allergy (P = .035) or asthma (P = .002) or an asthmatic father (P = .022). The cortisol stress response was greater in infants of mothers with allergy (P = .045) or asthma (P = .039), those with fewer siblings (P = .066), and those not entering day care early in life (P = .017). CONCLUSIONS: These alterations in both basal and stress levels of endogenous cortisol among infants predisposed to allergic disease might affect the development of allergic immune responses early in life through interactions with inflammatory mediators.

Blocking and unblocking in human causal learning.

Three experiments sought to develop the suggestion that, under some circumstances, common associative learning mechanisms might underlie animal conditioning and human causal learning, by demonstrating, in humans, an effect analogous to the unblocking by reinforcer omission observed in animal conditioning. Experiment 1 found no such effect. Experiment 2, designed to prevent inhibitory influences that might have masked excitatory unblocking in Experiment 1, demonstrated unblocking, indicating common human-animal associative learning mechanisms in which the associability of a stimulus varies as a function of its predictive history. Experiment 3, using a similar design but with a procedure promoting application of rational inference processes, failed to detect the same unblocking effect, indicating that associative and cognitive mechanisms may influence human causal learning.