Disturbed cognitive functions after nasal provocation in patients with seasonal allergic rhinitis

Allergic rhinitis impairs working memory in association with drop of hippocampal - Prefrontal coupling

Allergic rhinitis (AR) is a chronic inflammatory disease frequently associated with a deficit in learning and memory. Working memory is an important system for decision making and guidance, which depends on interactions between the ventral hippocampus (vHipp) and the prelimbic prefrontal cortex (plPFC). It is still unclear whether AR influences the activity and coupling of these brain areas, which consequently may impair working memory. The current study aimed to examine alterations of the vHipp-plPFC circuit in a rat model of AR. Our results show decreased working memory performance in AR animals, accompanied by a reduction of theta and gamma oscillations in plPFC. Also, AR reduces coherence between vHipp and plPFC in both theta and gamma frequency bands. Cross-frequency coupling analyses confirmed a reduced interaction between hippocampal theta and plPFC gamma oscillations. Granger causality analysis revealed a reduction in the causal effects of vHipp activity on plPFC oscillations and vice versa. A significant correlation was found between working memory performance with disruption of functional connectivity in AR animals. In summary, our data show that in AR, there is a deficit of functional coupling between hippocampal and prefrontal network, and suggest that this mechanism might contribute to working memory impairment in individuals with AR.

Cognitive dysfunction and quality of life during pollen season in children with seasonal allergic rhinitis

BACKGROUND

Allergic rhinitis often gives rise to impaired quality of life and is believed to also affect cognitive function. We aimed to examine whether cognitive functions were impaired during grass pollen season in symptomatic allergic children and to relate the degree of impairment to quality of life and biomarkers related to stress and inflammation.

METHODS

Forty-three grass pollen-allergic children (age 8-17 years) with non-satisfactory effect of medication (antihistamines and nasal steroids daily) during previous seasons were included. In addition, 26 matched non-allergic children were included as controls. Both groups performed cognitive tests (CANTAB) and completed Quality of Life questionnaires outside and during the pollen season. Blood samples were collected and analyzed for stress and inflammatory biomarkers. Pollen level was measured daily.

RESULTS

Impaired cognitive function was found in spatial working memory, where the allergic group made more errors compared to the non-allergic group during pollen season, but not off-season. No significant differences could be seen between the allergic group and the controls in the other tests investigating visual memory or attention. Quality of health questionnaires revealed more symptoms and impaired quality of life in allergic compared to non-allergic children, and increased symptoms in allergic children were associated with longer reaction time for simple movement during pollen season. No differences in stress or inflammatory biomarkers could be found between the groups.

CONCLUSION

Cognitive function was affected during pollen season in pollen-allergic children, and the more symptoms the allergic children had, the longer the reaction time in the cognitive tests.

Future Direction in Rhinoplasty: Functional Improvements for a Better Outcome

The nose plays both an aesthetic and functional role in the human body. Physiologically, the nose is an important part of the upper airway. Aesthetically, it is the central focal point of the face. Thus, rhinoplasty has evolved to be both an aesthetic and functional surgery, as the manipulation of the aesthetic subunits of the nose inadvertently leads to the functional alterations of the nose. While the aesthetic goals of rhinoplasty are well described in the literature, functional outcomes from rhinoplasty have been more challenging to delineate. Rhinoplasty can have an impact on the sense of smell, sleep apnea, oxygenation, cognitive function, cardiovascular function, and voice. We have systematically reviewed the current literature in regard to functional rhinoplasty and septoplasty to summarize current surgical maneuvers and their impact on nasal function, along with physiological and perceived functional changes from rhinoplasty.

The effect of nasal provocation with a single-dose allergen on the physical and cognitive performance of patients with ragweed allergy

Purpose This study aims to compare the impact of active allergic rhinitis on physical and cognitive abilities of trained allergic athletes to untrained allergic patients. Methods Cognitive, respiratory, and fitness functions were assessed before and after allergen exposure. Participants in both groups were provoked intranasally with ragweed allergen. Results The group of athletes revealed significantly higher average values in peak inspiratory flow and fitness index before and after provocation. In neuropsychological assessments, athletes performed significantly better after allergen provocation in complex working memory capacity. Due to single acute allergen exposure, the size of the nasal cavity and nasal inspiratory peak flow significantly decreased in both groups. The physical performance of both groups did not change after provocation. Executive functions and complex working memory capacity of athletes significantly improved resulting from provocation. Conclusions A single-shot allergen in high dose might cause an increase in mental concentration, which was more pronounced in the group of athletes. This study indicates that acute exposure to allergen cannot affect the physical performance and may result in increased mental focus in patients with allergy notwithstanding the declining respiratory functions.

Memory and multitasking performance during acute allergic inflammation in seasonal allergic rhinitis

BACKGROUND

In previous research, patients with seasonal allergic rhinitis (SAR) showed poorer school and work performance during periods of acute allergic inflammation, supporting the idea of an impact of SAR on cognitive functions. However, the specific cognitive domains particularly vulnerable to inflammatory processes are unclear.

OBJECTIVE

In this study, the influence of SAR on memory and multitasking performance, as two potentially vulnerable cognitive domains essential in everyday life functioning, was investigated in patients with SAR.

METHODS

Non-medicated patients with SAR (n = 41) and healthy non-allergic controls (n = 42) performed a dual-task paradigm and a verbal learning and memory test during and out of symptomatic allergy periods (pollen vs. non-pollen season). Disease-related factors (e.g. symptom severity, duration of symptoms, duration of disease) and allergy-related quality of life were evaluated as potential influences of cognitive performance.

RESULTS

During the symptomatic allergy period, patients showed (1) poorer performance in word list-based learning (P = 0.028) and (2) a general slowing in processing speed (P < 0.001) and a shift in processing strategy (P < 0.001) in multitasking. Yet, typical parameters indicating specific multitasking costs were not affected. A significant negative association was found between learning performance and duration of disease (r = -0.451, P = 0.004), whereas symptom severity (r = 0.326; P = 0.037) and quality of life (r = 0.379; P = 0.015) were positively associated with multitasking strategy.

CONCLUSIONS

Our findings suggest that SAR has a differentiated and complex impact on cognitive functions, which should be considered in the management of SAR symptoms. They also call attention to the importance of selecting sensitive measures and carefully interpreting cognitive outcomes.

Allergy Enhances Neurogenesis and Modulates Microglial Activation in the Hippocampus

Allergies and their characteristic T_H2-polarized inflammatory reactions affect a substantial part of the population. Since there is increasing evidence that the immune system modulates plasticity and function of the central nervous system (CNS), we investigated the effects of allergic lung inflammation on the hippocampus—a region of cellular plasticity in the adult brain. The focus of the present study was on microglia, the resident immune cells of the CNS, and on hippocampal neurogenesis, i.e., the generation of new neurons. C57BL/6 mice were sensitized with a clinically relevant allergen derived from timothy grass pollen (Phl p 5). As expected, allergic sensitization induced high serum levels of allergen-specific immunoglobulins (IgG1 and IgE) and of T_H2 cytokines (IL-5 and IL-13). Surprisingly, fewer Iba1⁺ microglia were found in the granular layer (GL) and subgranular zone (SGZ) of the hippocampal dentate gyrus and also the number of Iba1⁺MHCII⁺ cells was lower, indicating a reduced microglial surveillance and activation in the hippocampus of allergic mice. Neurogenesis was analyzed by labeling of proliferating cells with bromodeoxyuridine (BrdU) and determining their fate 4 weeks later, and by quantitative analysis of young immature neurons, i.e., cells expressing doublecortin (DCX). The number of DCX⁺ cells was clearly increased in the allergy animals. Moreover, there were more BrdU⁺ cells present in the hippocampus of allergic mice, and these newly born cells had differentiated into neurons as indicated by a higher number of BrdU⁺NeuN⁺ cells. In summary, allergy led to a reduced microglia presence and activity and to an elevated level of neurogenesis in the hippocampus. This effect was apparently specific to the hippocampus, as we did not observe these alterations in the subventricular zone (SVZ)/olfactory bulb (OB) system, also a region of high cellular plasticity and adult neurogenesis.

Altered performance in attention tasks in patients with seasonal allergic rhinitis: seasonal dependency and association with disease characteristics

BACKGROUND

Seasonal allergic rhinitis (SAR) is a chronic disease affecting about 23% of the European population with increasing prevalence rates. Beside classical symptoms (i.e., sneezing, nasal congestion), patients frequently complain about subjective impairments in cognitive functioning during periods of acute allergic inflammation. However, objective evidence for such deficits or the role of potential modulators and underlying mechanisms is limited. The present study aimed to investigate the effect of SAR on attention-related cognitive processes. In addition, relationships between attention performance, sleep and mood disturbances as well as specific disease characteristics as potential modulators of this link were explored.

METHOD

SAR patients (n = 41) and non-allergic healthy controls (n = 42) completed a set of attention tasks during a symptomatic allergy period and during a non-symptomatic period. Influences of sleep, mood, total immunoglobulin E (IgE) levels and individual allergy characteristics on cognitive performance were evaluated.

RESULTS

Compared to healthy controls, SAR patients had a slower processing speed during both symptomatic and non-symptomatic allergy periods. Additionally, they showed a more flexible adjustment in attention control, which may serve as a compensatory strategy. Reduction in processing speed was positively associated with total IgE levels whereas flexible adjustment of attention was linked with anxious mood. No association was found between SAR-related attention deficits and allergy characteristics or sleep.

CONCLUSIONS

SAR represents a state that is crucially linked to impairments in information processing and changes in attentional control adjustments. These cognitive alterations are more likely to be influenced by mood and basal inflammatory processes than sleep impairments or subjective symptom severity.

Allergic rhinitis is a risk factor for traffic safety

BACKGROUND

Allergic rhinitis (AR) affects up to 30% of the adult population and symptomatic patients continue to engage in daily life activities, including car driving. Previous studies have shown that AR can impair cognitive functions, especially during longer-lasting tasks. Other reports suggest negative effects on psychomotor functions such as driving, but no clear evidence has been presented yet.

OBJECTIVES

Primary objective was to determine the effect of AR per se on actual driving performance and compare it with the effects of treated AR.

METHODS

Nineteen patients with documented AR history underwent a unique and validated 1-h on-the-road driving test outside the pollen season. In a 4-leg repeated measures design, patients underwent a nasal provocation test with either pollen or inactive control prior to the driving test. In the three conditions with pollen provocation, patients were pretreated with either cetirizine 10 mg, fluticasone furoate 27.5 μg, or placebo to alleviate the provoked AR symptoms.

RESULTS

The driving performance of patients when symptomatic and not treated was significantly impaired compared to the placebo condition. When engaging in a secondary memory task during driving, their performance deteriorated further. The magnitude of impairment was relevant and comparable to that seen at a blood alcohol level of 0.05%, the legal limit in many countries. Treatment of AR symptoms partially counteracted the effect of AR on driving.

CONCLUSIONS

Untreated AR can impair driving ability and put patients at risk. Drug therapy reduces this impairment, and AR patients should therefore be advised to always treat their condition.

On-the-road driving performance and driving-related skills in older untreated insomnia patients and chronic users of hypnotics

RATIONALE

Many older adults report sleep problems and use of hypnotics. Several studies have shown that hypnotics can have acute adverse effects on driving the next morning. It is unclear however whether driving of chronic hypnotic users is impaired. Therapeutic effects on insomnia and development of tolerance may reduce the residual effects on driving.

OBJECTIVES

The present study aimed to compare actual driving performance and driving-related skills of chronic hypnotic users to good sleepers. To determine whether insomnia itself affects driving performance, driving and driving-related skills were compared between insomnia patients who do not or infrequently use hypnotics and good sleepers.

METHODS

Twenty-two frequent users of hypnotics (using hypnotics ≥ 4 nights per week for more than 3 months), 20 infrequent users (using hypnotics ≤ 3 nights per week), and 21 healthy, age-matched controls participated in this study. On the night before testing, all subjects were hospitalized for an 8-h sleep recorded by polysomnography. Frequent hypnotic users used their regular medication at bedtime (2330 hours), while infrequent users and controls received no medication. Cognitive performance (word learning, digit span, tracking, divided attention, vigilance, and inhibitory control) was assessed 8.5 h and driving performance between 10 and 11 h after bedtime and dosing.

RESULTS

Polysomnographic recordings did not significantly differ between the groups, but the insomnia patients, treated or untreated, still reported subjective sleep complaints. Results show no differences in driving performance and driving-related skills between both groups of insomnia patients and controls.

CONCLUSIONS

Driving performance in chronic users of hypnotics and untreated insomnia patients is not impaired. For chronic users, this may be due to prescription of relatively safe drugs and low doses. For untreated insomniacs, this corroborates previous findings showing an absence of neuropsychological deficits in this group of patients.

Perceived stress predicts allergy flares

BACKGROUND

A relation between stress and symptoms of rhinitis has not been established.

OBJECTIVE

To determine if participants' reporting of allergy flares correlated with perceived emotional stress, depression, mood, and a biomarker of stress (cortisol).

METHODS

This study was a secondary analysis of 179 university employees who participated in a study evaluating the influence of several lifestyle interventions on health symptoms and inflammation. Perceived stress and depressive symptom questionnaires were obtained before each 2-week study period. Online diary entries documenting same-day allergy flares, stressful events, perceived stress, mood, and salivary cortisol levels were collected daily during 2 14-day blocks.

RESULTS

Thirty-nine percent of subjects (n = 69) self-reported allergy symptoms. This allergy flare group had higher perceived stress scores than the group without allergy symptoms. Perceived stress, but not depressive symptoms, positively correlated with allergy flares evaluated during 2 independent 14-day periods. There also was a positive relation between negative mood scores and allergy flares over the course of the study. Cortisol had no association with allergy symptom flares.

CONCLUSION

These findings suggest that individuals with persistent emotional stress have more frequent allergy flares. Furthermore, those with more flares have greater negative mood.

Prevalence of allergy and upper respiratory tract symptoms in runners of the London marathon

BACKGROUND

The prevalence of self-reported upper respiratory tract (URT) symptoms in athletes has been traditionally associated with opportunistic infection during the temporal suppression of immune function after prolonged exercise. There is little evidence for this, and a competing noninfectious hypothesis has been proposed, whereby the exercise-induced immune system modulations favor the development of atopy and allergic disease, which manifests as URT symptoms. The aim of this study was to examine the association between allergy and URT symptoms in runners after an endurance running event.

METHODS

Two hundred eight runners from the 2010 London Marathon completed the validated Allergy Questionnaire for Athletes (AQUA) and had serum analyzed for total and specific immunoglobulin E response to common inhalant allergens. Participants who completed the marathon and nonrunning controls who lived in the same household were asked to complete a diary on URT symptoms.

RESULTS

Forty percent of runners had allergy as defined by both a positive AQUA and elevated specific immunoglobulin E. Forty-seven percent of runners experienced URT symptoms after the marathon. A positive AQUA was a significant predictor of postmarathon URT symptoms in runners. Only 19% of nonrunning controls reported symptoms.

CONCLUSIONS

The prevalence of allergy in recreational marathon runners was similar to that in elite athletes and higher than that in the general population. There was a strong association between a positive AQUA and URT symptoms. The low proportion of households in which both runners and nonrunners were symptomatic suggests that the nature of symptoms may be allergic or inflammatory based rather than infectious. Allergy is a treatable condition, and its potential effect on performance and health may be avoided by accurate clinical diagnosis and management. Both athletes' and coaches' awareness of the potential implications of poorly managed allergy needs to be raised.

Atopic dermatitis causes lipid accumulation in the liver of NC/Nga mouse

Various factors have been reported to influence lipid metabolism and cause metabolic syndrome. However, the influence of allergy on the liver that plays important role of lipid metabolism has not been clarified. The aim of this study was to examine the influence of allergy on lipid metabolism of liver. A model of atopic dermatitis was developed in the NC/Nga mouse using picryl chloride to induce allergy. Lipid metabolism parameters were measured and the mechanism of changes in these parameters was examined using DNA microarray analysis and quantitative reverse transcriptase PCR. Triacylglycerol accumulation was promoted in the liver in the mouse atopic dermatitis model despite reductions in food intake, body weight gain, and serum glucose. As this mechanism, it was thought that atopic dermatitis caused the suppression of fatty acid β-oxidation. These results suggest that atopic dermatitis causes lipid accumulation in the liver.

Blunted HPA axis responsiveness to stress in atopic patients is associated with the acuity and severeness of allergic inflammation

Previously we could demonstrate attenuated responsiveness of the hypothalamus-pituitary-adrenal (HPA) axis to stress in patients with chronic allergic inflammatory disease (i.e., atopic dermatitis, allergic asthma). The present study was designed to investigate HPA axis function in an acute manifestation of allergy. Patients with seasonal allergic rhinitis (SAR; n = 20) and non-atopic controls (n = 20) were exposed to a standardized laboratory stressor ('Trier Social Stress Test'; TSST). Cortisol responses to the TSST and cortisol awakening responses (CAR) were measured in SAR subjects while suffering from acute symptoms of SAR (pollen season), and during a non-active state of their disease (pollen-free season). To assess the acuity and severity of SAR, eosinophil and basophil numbers and SAR symptomatology were determined. Non-allergic control subjects were examined at identical times during the year. To control for possible sequence effects, a cross-over design was used. SAR patients showed significantly increased symptom severity (t = 9.4; p<.001) as well as eosinophil (F(1,31) = 9.8; p<.01) and basophil (F(1,38) = 6.4; p<.05) numbers during the pollen season when compared to a pollen-free period. When exposed to the TSST, significantly attenuated cortisol responses were found in SAR subjects during acute manifestation of the disease (pollen season) when compared to the pollen-free season (F(16,456) = 1.65; p<.05). In SAR patients, there was a significant negative correlation between symptom severity and the cortisol response to the stressor (r = .53; p<.05). No significant between-group or between-condition differences with respect to the CAR could be determined (all p>.05). These findings support previous data of attenuated HPA axis responsiveness to stress in atopic conditions and further, suggest that HPA axis hyporesponsiveness in atopy may be linked to the severity of the allergic inflammatory process.