Is psoriasis associated with dementia or cognitive impairment? A Critically Appraised Topic

Do Atopic Dermatitis and Psoriasis Have an Impact on Cognitive Decline-Latest Research Review

BACKGROUND

Atopic dermatitis and psoriasis are chronic skin diseases that affect the mental health of patients. The relationship between AD and psoriasis and cognitive processes in patients remains unclear. The aim of the review was to answer the question of whether AD and psoriasis have an impact on cognitive decline in patients.

METHOD

A systematic literature search was conducted on PubMed and EBSCO to identify case-control, cross-sectional, or cohort studies that evaluated the association between atopic dermatitis and psoriasis and cognitive impairment.

RESULTS

Most of the studies included in the review confirmed cognitive decline in patients with atopic dermatitis and psoriasis.

CONCLUSIONS

It seems that atopic dermatitis and psoriasis may negatively affect cognitive processes such as working memory, concentration, attention, and speed of motor reactions. Psychological interventions targeting distorted cognitive processing could improve the quality of life of patients with atopic dermatitis and psoriasis.

T cell-mediated skin-brain axis: Bridging the gap between psoriasis and psychiatric comorbidities

Psoriasis, a chronic inflammatory skin condition, is often accompanied by psychiatric comorbidities such as anxiety, depression, suicidal ideation, and other mental disorders. Psychological disorders may also play a role in the development and progression of psoriasis. The intricate interplay between the skin diseases and the psychiatric comorbidities is mediated by the 'skin-brain axis'. Understanding the mechanisms underlying psoriasis and psychiatric comorbidities can help improve the efficacy of treatment by breaking the vicious cycle of diseases. T cells and related cytokines play a key role in the pathogenesis of psoriasis and psychiatric diseases, and are crucial components of the 'skin-brain axis'. Apart from damaging the blood-brain barrier (BBB) directly, T cells and secreted cytokines could interact with the hypothalamic-pituitary-adrenal axis (HPA axis) and the sympathetic nervous system (SNS) to exacerbate skin diseases or mental disorders. However, few reviews have systematically summarized the roles and mechanisms of T cells in the interaction between psoriasis and psychiatric comorbidities. In this review, we discussed several key T cells and their roles in the 'skin-brain axis', with a focus on the mechanisms underlying the interplay between psoriasis and mental commodities, to provide data that might help develop effective strategies for the treatment of both psoriasis and psychiatric comorbidities.

Altered brain activity and cognitive impairment in patients with psoriasis

BACKGROUND

Patients with psoriasis may have cognitive impairment. However, there is limited information regarding intrinsic brain activity and cognitive function in patients with psoriasis.

OBJECTIVES

This study aim to assess alterations of intrinsic brain activity and its association with cognitive function in patients with psoriasis.

METHODS

A total of 222 patients with psoriasis aged 18-70 years and 144 age and gender-matched healthy controls (HCs) were enrolled into this study. All subjects underwent brain resting-state functional magnetic resonance imaging (rs-fMRI) and neuropsychological testing. The rs-fMRI data were analysed for both intrinsic brain activity as indicated by amplitude of low-frequency fluctuation (ALFF) and seed-based functional connectivity (FC). Correlative analysis of brain activity with cognitive assessment was performed.

RESULTS

Compared with the HCs, patients with psoriasis had worse cognitive performance in the Trail Making Test, Digit Span Test and Stroop Color-Word Test (p < 0.05). Patients with psoriasis showed decreased ALFF in the left superior frontal gyrus, the left medial superior frontal gyrus and the right precuneus gyrus; as well as enhanced ALFF in the left paracentral lobule (pFWE  < 0.05). Significant correlations were noted between the altered ALFF in the four brain regions and cognitive assessment (p < 0.05). Moreover, patients with psoriasis had increased FC between the four brain regions with altered ALFF (seeds) and the left prefrontal gyrus, the left anterior cingulate gyrus, left superior parietal lobule and default mode network (DMN) regions such as the right precuneus gyrus, left inferior parietal lobule, right angular gyrus and bilateral inferior temporal gyrus (pFWE  < 0.05).

CONCLUSIONS

Patients with psoriasis had altered brain activity and connectivity in the key brain areas within the DMN-prefrontal circuit. These brain changes may be the underlying neural correlates for cognitive functioning in patients with psoriasis.

Circadian Oscillations of Minimal Erythema Dose (MED) are Also Influenced by Diet in Patients with Psoriasis: A Chronomedical Study

INTRODUCTION

Minimal erythema dose (MED) remains a parameter of paramount importance to orient narrow-band (NB)-UVB phototherapy in psoriatic (PsO) patients. Recently, circadian rhythm and diet were recognized as potential MED modulators, but their mutual interaction remains understudied. Thus, we aimed to evaluate the potential diet modulation of MED circadian oscillations.

METHODS

In the first phase, a cohort study was performed comparing potential MED oscillations (morning, afternoon, and evening) among omnivorous psoriatic patients before and after a phototherapy cycle and omnivorous healthy controls. The two groups were age-, gender-, skin-type-, MED-, and diet-matched. Then, in the second phase, another cohort study was carried out comparing MED oscillations 24 h after the last phototherapeutic session only in psoriatic patients cleared with NB-UVB and undergoing different diets (vegan, vegetarian, paleo , ketogenic, intermittent circadian fasting, and omnivore). Patients with different diets were age-, gender-, and skin-type matched.

RESULTS

In the first phase, we enrolled only omnivores, specifically 54 PsO patients and 54 healthy individuals. Their MED before and after NB-UVB therapy changed significantly among the three different time-points (morning, afternoon, and evening) (p < 0.001). The time effect was statistically significant in both groups before and after phototherapy. In the second phase, we enrolled 144 PsO patients (vegan, vegetarian, paleo, ketogenic, intermittent circadian fasting, and omnivore). MED circadian oscillations preserved a significant difference also after clearance and were influenced by diet type and time of day (p < 0.001). In particular, vegans displayed the lowest MED values, whilst Ramadan fasting showed the highest values in morning, afternoon, and evening.

CONCLUSIONS

Diet, like other ongoing therapies, should be reported in the medical records of patients with psoriasis undergoing NB-UVB and patients with lower MEDs should be preferentially treated in the morning when the MED is higher.

Cognitive impairment in the immune-mediated inflammatory diseases compared with age-matched controls: Systematic review and meta-regression

OBJECTIVES

To compare the magnitude of cognitive impairment against age-expected levels across the immune mediated inflammatory diseases (IMIDs: systemic lupus erythematosus [SLE], rheumatoid arthritis [RA], axial spondyloarthritis [axSpA], psoriatic arthritis [PsA], psoriasis [PsO]).

METHODS

A pre-defined search strategy was implemented in Medline, Embase and Psychinfo on 29/05/2021. Inclusion criteria were: (i) observational studies of an IMID, (ii) healthy control comparison, (iii) measuring cognitive ability (overall, memory, complex attention/executive function, language/verbal fluency), and (iv) sufficient data for meta-analysis. Standardised mean differences (SMD) in cognitive assessments between IMIDs and controls were pooled using random-effects meta-analysis. IMIDs were compared using meta-regression.

RESULTS

In total, 65 IMID groups were included (SLE: 39, RA: 19, axSpA: 1, PsA: 2 PsO: 4), comprising 3141 people with IMIDs and 9333 controls. People with IMIDs had impairments in overall cognition (SMD: -0.57 [95% CI -0.70, -0.43]), complex attention/executive function (SMD -0.57 [95% CI -0.69, -0.44]), memory (SMD -0.55 [95% CI -0.68, -0.43]) and language/verbal fluency (SMD -0.51 [95% CI -0.68, -0.34]). People with RA and people with SLE had similar magnitudes of cognitive impairment in relation to age-expected levels. People with neuropsychiatric SLE had larger impairment in overall cognition compared with RA.

CONCLUSIONS

People with IMIDs have moderate impairments across a range of cognitive domains. People with RA and SLE have similar magnitudes of impairment against their respective age-expected levels, calling for greater recognition of cognitive impairment in both conditions. To further understand cognition in the IMIDs, more large-scale, longitudinal studies are needed.

Association of autoimmune diseases with Alzheimer's disease: A mendelian randomization study

BACKGROUND

Alzheimer's disease may have an autoimmune component, but the association is unclear.

OBJECTIVE

The objective of this Mendelian randomization (MR) study was to evaluate the association of liability to autoimmune diseases with Alzheimer's disease.

METHODS

A systematic search was done using PubMed to identify autoimmune diseases that have been suggested as associated with Alzheimer's disease. Genetic predictors of these autoimmune diseases were obtained from the largest and most recent genome-wide association studies (GWAS). Genetic associations with clinically-diagnosed Alzheimer's disease were obtained from the International Genomics of Alzheimer's Project GWAS (21982 cases; 41944 controls); and with parental and sibling history of Alzheimer's disease from the UK Biobank GWAS (27696 maternal, 14338 paternal and 2171 sibling cases). MR estimates were obtained using inverse variance weighting, MR-Egger and weighted median. To address possible selection bias due to inevitably recruiting only survivors, the analysis was repeated in younger people, i.e., UK Biobank siblings and adjusting for competing risk of Alzheimer's disease.

RESULTS

Of the 7 autoimmune diseases considered, liability to psoriasis and sarcoidosis were not associated with Alzheimer's disease. Some evidence was found for liability to multiple sclerosis being associated with higher risk and liability to Sjogren's syndrome with lower risk of Alzheimer's disease. Associations found for liability to giant cell arteritis, type 1 diabetes and rheumatoid arthritis were inconsistent in sensitivity analyses.

CONCLUSION

Liability to multiple sclerosis and Sjogren's syndrome could be associated with Alzheimer's disease. The underlying mechanisms, such as the role of myelin and neuroinflammation, should be further investigated.

Abnormal functional connectivity in psoriasis patients with depression is associated with their clinical symptoms

Psoriasis is a chronic, autoimmune disorder that is related to mental health disorders such as depression. However, few studies have focused on the features of brain activity in psoriasis patients with depression (PPD) and the association between brain activity and disease severity. A total of 29 PPD and 24 healthy controls were involved in this study, and all participants underwent resting-state functional magnetic resonance imaging (fMRI) scanning. The psoriasis area and severity index (PASI) and the self-rating depression scale (SDS) were used to measure clinical symptoms. Compared with HCs, PPD patients showed increased fractional amplitude of low-frequency fluctuation (fALFF) in the Frontal_Mid_L and increased functional connectivity (FC) between the hypothalamus-R and the Cingulum_Mid_R. Correlation analysis suggested a positive correlation between PASI and SDS scores in PPD, while the fALFF and FC values were negatively correlated with their SDS and PASI scores. These brain regions may be associated with the development of depressive symptoms and disease severity in psoriasis patients.

The prevalence of alexithymia in psoriasis: A systematic review and meta-analysis

OBJECTIVES

Alexithymia is characterized by an inability to identify and describe feelings, which may increase the psychological burden of patients with psoriasis. The prevalence of alexithymia in psoriasis has been investigated with variable results. This study aimed to estimate the overall alexithymia prevalence in psoriasis.

METHODS

The PubMed, PsycInfo, Web of Science, The Cochrane Library, EMBASE, China Knowledge Resource in Integrated Database (CNKI), WanFang Database, Weipu Database (VIP), and Chinese Biomedical Database (CBM) electronic databases were searched from inception to March 28, 2022, for cross-sectional studies, that reported prevalence of alexithymia. The included studies were evaluated for quality, data synthesis, subgroup analysis, sensitivity analysis, and publication bias.

RESULTS

This systematic review and meta-analysis included 16 articles involving 3752 patients with psoriasis from eight countries. The pooled prevalence of alexithymia was 28% (95% CI: 25-32%), with heterogeneity between studies (I² = 80.03%, p < .001). There was a higher prevalence of alexithymia in women with psoriasis, patients with a Psoriasis Area Severity Index (PASI) score >10, patients with psoriatic arthritis, and patients with psoriasis with visible skin lesions had a higher prevalence of alexithymia.

CONCLUSION

More than a quarter of people with psoriasis have alexithymia., But due to the small sample size of the included studies, the results of the subgroup analysis should be interpreted with caution. More research is needed to elucidate the mechanism of alexithymia development in psoriasis. These findings may provide a theoretical basis for the screening and intervention of alexithymia in patients with psoriasis.

Moxifloxacin Disrupts and Attenuates Aβ42 Fibril and Oligomer Formation: Plausibly Repositioning an Antibiotic as Therapeutic against Alzheimer's Disease

The aggregation of Aβ42 is established as a key factor in the development of Alzheimer's disease (AD). Consequently, molecules that inhibit aggregation of peptide may lead to therapies to prevent or control AD. Several studies suggest that oligomeric intermediates present during aggregation may be more cytotoxic than fibrils themselves. In this work, we examine the inhibitory activity of an antibiotic MXF on aggregation (fibrils and oligomers) and disaggregation of Aβ42 using various biophysical and microscopic studies. Computational analysis was done to offer mechanistic insight. The amyloid formation of Aβ42 is suppressed by MXF, as demonstrated by the decrease in both the corresponding ThT fluorescence intensity and other biophysical techniques. The lag phase of amyloid formation doubled from 4.53 to 9.66 h in the presence of MXF. The addition of MXF at the completion of the fibrillation reaction, as monitored by ThT, led to a rapid, concentration dependent, exponential decrease in fluorescence signal that was consistent with loss of fibrils. We used TEM to directly demonstrate that MXF caused fibrils to disassemble. Our docking results show that MXF binds to both monomeric and fibrillar forms of Aβ42 with significant affinities. We also observed breaking of fibrils in the presence of MXF through molecular dynamics simulation. These findings suggest that antibiotic MXF could be a promising lead compound with dual role as fibril/oligomer inhibitor and disaggregase for further development as potential repurposed therapeutic against AD.

Cognitive impairment in psoriasis patients: a systematic review of case-control studies

Introduction

Cognitive impairment in chronic diseases such as psoriasis is an increasing clinical challenge.

Objective

To assess the frequency and extent of difficulties in cognitive functioning in people with psoriasis compared to healthy people.

Patients and methods

The systematic review was carried out on the 23rd July, 2021 by two trained psychologists resulting in a selection of 11 studies on 971 patients with psoriasis and 10,242 controls.

Results

A review of the studies showed irregularities in many cognitive domains, including working memory processes, executive functions, long-term verbal memory, attention, and the visuospatial domain. Depending on the methods used to assess cognitive dysfunctions and the characteristics of patients in different studies, large differences in the frequency of cognitive impairment in patients with psoriasis were observed, ranging from 0 to 91.9%.

Conclusions

The authors conclude that there is a need for longitudinal studies to identify factors important for the development and persistence of cognitive impairment in psoriatic patients.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00415-022-11317-2.

Epidemiology of Psoriasis and Comorbid Diseases: A Narrative Review

Psoriasis is a chronic autoimmune inflammatory disease that remains active for a long period, even for life in most patients. The impact of psoriasis on health is not only limited to the skin, but also influences multiple systems of the body, even mental health. With the increasing of literature on the association between psoriasis and extracutaneous systems, a better understanding of psoriasis as an autoimmune disease with systemic inflammation is created. Except for cardiometabolic diseases, gastrointestinal diseases, chronic kidney diseases, malignancy, and infections that have received much attention, the association between psoriasis and more systemic diseases, including the skin system, reproductive system, and oral and ocular systems has also been revealed, and mental health diseases draw more attention not just because of the negative mental and mood influence caused by skin lesions, but a common immune-inflammatory mechanism identified of the two systemic diseases. This review summarizes the epidemiological evidence supporting the association between psoriasis and important and/or newly reported systemic diseases in the past 5 years, and may help to comprehensively recognize the comorbidity burden related to psoriasis, further to improve the management of people with psoriasis.

Cognitive Functions Associated with Brain Imaging Markers in Patients with Psoriasis

Psoriasis is a severe inflammatory disease associated with a higher comorbidity of depression, cognitive dysfunction and brain atrophy. The association between psoriasis, magnetic resonance imaging (MRI) markers and cognitive impairment has rarely been investigated, and the existing results are conflicting. Methods. This study included 89 subjects (53 patients with psoriasis and 36 healthy controls). The severity of psoriasis was evaluated using the Psoriasis Area and Severity Index (PASI) score; for depression, the Hospital Anxiety and Depression Scale (HADS) scale was used. Neuropsychological tests were also applied, including a Trail Making Test (TMT) as well as Digit Span, Stroop, Verbal Fluency and Rey Auditory Verbal Learning tests. MRI scans were performed using a 1.5 T scanner. Brain volumetry, white matter lesions, grey matter and white matter were evaluated. The extent of these changes was assessed on the Fazekas scale. The differences between groups were evaluated using a Student’s t-test and a Mann-Whitney U test, and a Pearson correlation analysis was also performed. Results. Patients with psoriasis presented worse achievements on all the neuropsychological tests and showed more intense changes on MRI compared to healthy controls. The severity of psoriasis as determined by PASI scores was associated with depression, and a greater psychomotor slowness severity of changes in the brain was associated with poorer results on the neurological tests. Conclusions. Our results indicate the possibility of progressive brain atrophy related to cognitive decline in psoriasis.

The Relationship between Alexithymia and Mental Health Is Fully Mediated by Anxiety and Depression in Patients with Psoriasis

Background: Psoriasis is a common skin disease that affects quality of life, especially mental health. Alexithymia has been considered a relevant feature in psoriasis patients. Moreover, psoriasis was found to be associated with negative psychological health, including anxiety and depression. As the pathways linking alexithymia and mental health remain unclear among patients with psoriasis, we aimed to examine the mediating role of anxiety and depression in the relationship between alexithymia and mental health in these patients. Methods: To explore our variables of interest, we used the Toronto Alexithymia Scale (TAS-20), the 12-Item Short Form Health Survey (SF-12), and the Hospital Anxiety and Depression Scale (HADS). Results: Forty-four percent of patients were alexithymic and reported higher anxiety and depression, and lower quality of life compared to non-alexithymic patients. Alexithymic patients also had lower educational attainment. A correlation analysis showed positive associations between alexithymia and both anxiety and depression, whereas mental and physical health were negatively associated with alexithymia. Moreover, anxiety and depression fully mediated the relationship between alexithymia and mental health. Conclusions: Our findings highlight the importance of assessing alexithymia and psychological distress in clinical practice to identify vulnerable patients and to implement interventions aimed at improving negative emotional states.

Past, present and future of therapeutic strategies against amyloid-β peptides in Alzheimer's disease: a systematic review

Alzheimer's disease (AD) is the most prevalent neurodegenerative disease in ageing, affecting around 46 million people worldwide but few treatments are currently available. The etiology of AD is still puzzling, and new drugs development and clinical trials have high failure rates. Urgent outline of an integral (multi-target) and effective treatment of AD is needed. Accumulation of amyloid-β (Aβ) peptides is considered one of the fundamental neuropathological pillars of the disease, and its dyshomeostasis has shown a crucial role in AD onset. Therefore, many amyloid-targeted therapies have been investigated. Here, we will systematically review recent (from 2014) investigational, follow-up and review studies focused on anti-amyloid strategies to summarize and analyze their current clinical potential. Combination of anti-Aβ therapies with new developing early detection biomarkers and other therapeutic agents acting on early functional AD changes will be highlighted in this review. Near-term approval seems likely for several drugs acting against Aβ, with recent FDA approval of a monoclonal anti-Aβ oligomers antibody -aducanumab- raising hopes and controversies. We conclude that, development of oligomer-epitope specific Aβ treatment and implementation of multiple improved biomarkers and risk prediction methods allowing early detection, together with therapies acting on other factors such as hyperexcitability in early AD, could be the key to slowing this global pandemic.

A preliminary study about neurofilament light chain and tau protein levels in psoriasis: Correlation with disease severity

BACKGROUND

Studies investigating cognitive dysfunction in psoriatic patients remain inconclusive.

OBJECTIVE

To investigate the risk of cognitive decline in plaque-type psoriasis patients.

METHODS

Serum neurofilament light chain (NFL) and tau protein concentrations in 45 patients with plaque-type psoriasis and forty-five healthy controls were measured by enzyme-linked immunosorbent assay (ELISA).

RESULTS

Mean homeostasis model assessment (HOMA-IR) values (6.82 vs 3.25) and serum levels of insulin (28.19 vs 15.71), NFL (5.74 vs 1.98), and tau (348.17 vs 207.30) in patients with psoriasis were found to be significantly higher than those of in healthy controls. There was a significant positive correlation between NFL and tau (r = .257, P = .015). There was significant correlation between NFL, tau and PASI (r = .310, P = .040) and (r = .383, P = .010), respectively. Significant correlations between NFL and insulin, TC, HDL-C, TG, VLDL-C, and BMI were found. NFL (9.38 vs 3.08) and tau (439.28 vs 281.58) concentrations and PASI values (23.94 vs 14.18) in patients with disease onset before 40 years were significantly higher than that of the patients with disease onset after 40 years. C-reactive protein (CRP) was significantly correlated with BMI (r = .449, P < .001), LDL-C (r = .240, P = .026), TG (r = .244, P = .024), and VLDL-C (r = .241, P = .025) in patients with psoriasis.

CONCLUSIONS

Increased serum NFL and tau protein levels and the presence of positive correlations between NFL, tau protein and PASI score show cognitive decline risk may be higher in moderate-to-severe psoriasis.