Association Between Psoriasis and Dementia: A Retrospective Cohort Study

Psoriasis and dementia: A population-based matched cohort study of adults in England

OBJECTIVE

Evidence for an association between psoriasis and dementia is limited and conflicting. We aimed to investigate the association using large and representative population-based data and describe risk by dementia subtype and over time.

METHODS

We compared dementia risk between people with and without psoriasis using an age-, sex- and primary care practice-matched cohort of adults aged ≥40 years from the Clinical Practice Research Datalink Aurum in England (1997-2021) linked to hospital admissions data, analysed with stratified Cox regression.

RESULTS

Among 360,014 individuals with psoriasis and 1,799,617 without, psoriasis was associated with a small increased risk of all-cause dementia (adjusted hazard ratio [aHR] 1.06, 95% CI 1.04-1.08; absolute rate difference 24 per 100,000 person-years). Strength of association increased with time since psoriasis diagnosis (e.g. aHR 0.99, 0.96-1.03 within 0 to 5 years; 1.20, 1.05-1.37 within 20 to 25 years). The association was stronger for vascular dementia (aHR 1.10, 1.06-1.14) than Alzheimer's dementia (aHR 1.03, 1.00-1.06). Hazard ratios were larger for severe psoriasis (all-cause aHR 1.32, 1.25-1.39; vascular aHR 1.58, 1.44-1.74; Alzheimer's aHR 1.11, 1.02-1.21).

INTERPRETATION

Long-term risk of all-cause dementia and vascular dementia, but not Alzheimer's dementia, was slightly higher in people with psoriasis, but absolute risk differences were small. Risks were more substantially raised with time since psoriasis diagnosis and in severe psoriasis compared to mild to moderate psoriasis, suggesting a potential dose-response relationship.

Exploring role of citrus fruits in comorbid neurodegenerative disorders associated with psoriasis

A neurodegenerative illness is a disorder in which the brain and/or spinal cord's neurons, or nerve cells, gradually deteriorate and disappear. These illnesses often get worse with time and can seriously affect movement, cognition, and other neurological functions. Psoriasis is a long-term autoimmune skin condition marked by fast skin cell growth that results in red, elevated areas coated in silvery-white scales. It can affect several body parts, such as the elbows, knees, scalp, and lower back, and it is not communicable. The build-up of amyloid beta [Aβ] protein is linked to elevated levels of reactive oxygen species (ROS) (Kim et al. 2020). These ROS can trigger multiple pathways, including MAPK, NFkB, JAK/STAT, and interleukin 1 beta (IL-1β), ultimately playing a role in the development of neurodegenerative illnesses like Alzheimer's disease (AD) and psoriasis. People who have psoriasis are more likely to acquire AD, as psoriasis is a chronic inflammatory skin condition that is genetically connected. Because of the antioxidants and anti-inflammatory properties of citrus fruits neurodegenerative and psoriasis disease may be prevented. The neuroprotective action of bioactives in citrus fruits involves the inhibition of inflammation through the control of p38 mitogen-activated protein kinase (MAPK) and the activation of nuclear factor erythroid 2-related factor 2 (Nrf2). Due to their immunomodulatory and anti-inflammatory qualities, polyphenols may be able to control the immune response in psoriasis. We performed a thorough review in order to investigate for the first time to understand the role of citrus fruits in comorbid neurodegenerative disorders associated with psoriasis. For better understanding into the possible applications of citrus fruits in treating psoriasis and neurodegenerative disease would require additional studies focusing directly on the relationship between citrus fruits consumption in managing neurodegenerative and psoriasis disease.

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.

Causal relationship between psoriasis vulgaris and dementia: Insights from Mendelian randomization analysis

Many clinical studies have demonstrated a correlation between psoriasis vulgaris and dementia, yet this correlation remains controversial. Our study employed the Mendelian randomization (MR) method to investigate the causal relationship between psoriasis vulgaris and dementia. Data were obtained from the summary statistics of the genome-wide association studies from IEU-OpenGWAS project database. In univariate Mendelian randomization (UVMR) analysis, psoriasis vulgaris was used as exposure. Alzheimer disease (AD), vascular dementia (VaD), dementia with Lewy bodies (DLB), Parkinson's disease with dementia (PDD) and frontotemporal dementia (FTD) served as the outcomes. In multivariate Mendelian randomization (MVMR) analysis, VaD served as the outcome. The first MVMR analysis used psoriasis vulgaris, mean platelet volume (MPV), platelet distribution width (PDW) and platelet count (PLT) as exposures. The second MVMR analysis used psoriasis vulgaris, vitamin D level and 25 hydroxyvitamin D level as exposures. The main analysis employed the inverse variance weighted method, and the outcomes were evaluated by odds ratio (OR) and 95% confidence interval (95% CI). In UVMR analysis, the results depicted that psoriasis vulgaris was associated with VaD (OR: 0.903, 95% CI: 0.818-0.996, p = 0.041). The results revealed insignificant associations between psoriasis vulgaris and other dementia types. After adjusting the effects of MPV, PDW and PLT in MVMR analysis, the association between psoriasis vulgaris and VaD was no longer significant (p = 0.164). Similarly, after adjusting the effects of vitamin D level and 25 hydroxyvitamin D level in MVMR analysis, the association between psoriasis vulgaris and VaD was also no longer significant (p = 0.533). Our study suggests that psoriasis vulgaris may potentially decrease VaD incidence. However, the causal association between psoriasis vulgaris and VaD may be impeded by platelet-related indices, vitamin D level and 25 hydroxyvitamin D level.

Risk Factors of Dental Caries in the Thai Population: The Retrospective Cohort Study

Aim

The aim of this retrospective cohort study was to determine the risk factors associated with the occurrence of dental caries increments in Thai dental patients.

Materials and Methods

The dental chart records of 500 patients who visited the Department of Advanced General Dentistry, Mahidol University during 2003-2013 were included in this research. Risk factors such as age, gender, medical history, marital status, routine oral checkup, oral appliance usage, initial and final records of decayed (DT)-missing-filled (DMF-T), dental history of tooth extraction due to caries, xerostomia, presence of visible plaque, presence of interproximal restoration, and caries risk level were retrieved from dental records. Cox proportional hazard regression model was used to determine the association of caries risk factors and new dental caries increments.

Results

The results indicated that the rate of incidence of new dental caries was 2.1 per 100 person-month. In the multivariate hazard model, past caries experience in more than three teeth (adjusted hazard ratio: 2.29, 95%CI: 1.53-3.44) and xerostomia (adjusted hazard ratio: 4.47, 95%CI: 1.82-10.98) were independent risk factors of dental caries increments. Other factors, such as demographic data, physical factors, clinical factors, and other contributing factors, were not associated with the incidence of new dental caries.

Conclusion

The presence of past caries experience and xerostomia were predictors of the occurrence of new dental caries.