Increased incidence of autoimmune thyroid disorders in patients with psoriatic arthritis: a longitudinal follow-up study

Thyroid abnormality in patients with psoriasis: prevalence and association with severity

BACKGROUND

Psoriasis is associated with several comorbidities and its association with thyroid abnormality has been hypothesized.

OBJECTIVE

To assess the prevalence of thyroid abnormality in Brazilian patients with psoriasis and to analyze its association with severity, presence of psoriatic arthritis and immunobiological treatment. Additionally, to compare results with literature as a control.

METHODS

In this observational study, clinical and laboratory data of patients followed from January 2018 to December 2019 were analyzed. Thyroid abnormality was assessed through the current history of thyroid disease and laboratory tests - thyrotropin (TSH), free thyroxine (FT4), antithyroid peroxidase (anti-TPO) and antithyroglobulin (anti-TG) antibodies. Patients were classified according to psoriasis severity - Psoriasis Area and Severity Index (PASI), presence of psoriatic arthritis, and current treatment. Subsequently, the results were compared with a control group selected from the literature review.

RESULTS

Of the 250 included patients, 161 were eligible. The prevalence of thyroid abnormality was 28.57% and of hypothyroidism, 14.91%. The mean age was 55 years and the median PASI was 2.2. There was no association between thyroid abnormality and PASI (p=0.8), presence of psoriatic arthritis (p=0.87), or use of immunobiological therapy (p=0.13). The literature control group included 6,227 patients and there was a statistically significant difference for the hypothyroidism variable (p<0.0001).

STUDY LIMITATIONS

Absence of a control group from the same center.

CONCLUSION

This was one of the first Brazilian studies on the prevalence of thyroid abnormality in patients with psoriasis.

Autoimmune Thyroid Disease in Psoriasis Patients: A Case-Control Study

INTRODUCTION

Psoriasis is a common immunologically mediated inflammatory disease characterized by skin inflammation, epidermal hyperplasia, an increased risk of painful and destructive arthritis, cardiovascular morbidity, and psychosocial challenges. Some autoimmune diseases are mediated by stimulating or blocking auto-antibodies. Auto-antibodies may act as antagonists and bind to hormone receptors, blocking receptor function. It may result in impaired secretion of mediators and gradual dysfunction of the affected organ, e.g., Graves disease and myasthenia gravis.

OBJECTIVE

This study was planned to evaluate the association between anti-thyroid peroxidase antibody (anti-TPO Ab) and anti-thyroglobulin antibody (anti-TG Ab) as biochemical markers in 30 clinically diagnosed psoriasis patients.

MATERIALS AND METHODS

This hospital-based, epidemiological case-control study was conducted in the Department of Biochemistry in collaboration with the Department of Dermatology, Venereology, and Leprology at Bhagat Phool Singh Government Medical College for Women, Khanpur Kalan, Sonepat, Haryana, India. Thirty subjects diagnosed clinically with psoriasis and an equal number of age-matched controls with no known autoimmune disease from the outpatient department were also enrolled. The following hormonal tests, i.e., thyroid-stimulating hormone (TSH), free triiodothyronine (FT3), free thyroxine (FT4), and antibodies, anti-TPO Ab and anti-TG Ab, were performed. The study period was one year. The data thus obtained was analyzed using SPSS Statistics version 26.0 (IBM Corp. Released 2019. IBM SPSS Statistics for Windows, Version 26.0. Armonk, NY: IBM Corp). The significance level (p-value) was taken as <0.05.

RESULTS

The mean age of psoriasis subjects was 37.83±12.89 years compared to 36.91±12.32 years in the control group and was found to be non-significant (p=0.432), reflecting a similar age distribution. A male preponderance was observed in the present study, where the psoriasis group consisted of 80% males and 20% females, while the control group had 60% males and 40% females. All six psoriasis patients diagnosed with autoimmune thyroid disease (AITD) were euthyroid at the time of enrollment, compared to only one control subject in a subclinical hypothyroid state. The mean values of anti-TPO Ab were 30.93±41.26 IU/mL in psoriasis patients and 11.39±28.42 IU/mL in the control group (p=0.001), while the mean values of anti-TG Ab were 11.21±27.69 IU/mL in psoriatic subjects and 2.49±9.05 IU/mL in the control group (p=0.004). No significant correlation between AITD and psoriasis was found when both parameters were analyzed statistically for correlation; even when one marker was considered, no significant correlation was found. The odds ratio was calculated to find an association between the disease and thyroid autoimmunity. The odds ratio was estimated to be 2.25 for psoriasis and the control group, with a confidence interval of 95% (0.77-6.59) and a p-value of 0.139, which was not statistically significant.

CONCLUSION

Psoriasis, a dermatological disorder, has been seen as related to AITD. The role of early detection of anti-thyroid antibodies, i.e., anti-TPO Ab and anti-TG Ab, can be of prognostic value in AITD and psoriasis.

[Autoimmune polyendocrine syndrome in adults. Focus on rheumatological aspects of the problem: A review]

Autoimmune polyglandular syndromes (APS) are a heterogeneous group of clinical conditions characterized by functional impairment of multiple endocrine glands due to loss of central or peripheral immune tolerance. These syndromes are also often accompanied by autoimmune damage to non-endocrine organs. Taking into account the wide range of components and variants of the disease, APS is usually divided into a rare juvenile type (APS 1) and a more common adult type (APS 2-4). APS type 1 is caused by a monogenic mutation, while APS types 2-4 have a polygenic mode of inheritance. One subtype of adult APS (APS 3D) is characterized by a combination of autoimmune thyroid disease and autoimmune rheumatic disease. This review considers the available literature data on combinations that meet the above criteria. Many studies have noted a significantly higher prevalence of rheumatic diseases in patients with autoimmune thyroid disease compared with the control group. Also, as in a number of rheumatic diseases, a more frequent occurrence of autoimmune thyroiditis, primary hypothyroidism and Graves' disease was noted.

Association between psoriasis and thyroid function: results from the Brazilian Longitudinal Study of Adults Health (ELSA-Brasil)

Objective

To determine the relationship between psoriasis, thyroid-stimulating hormone (TSH), free thyroxine (FT4), free triodothyronine (FT3), thyroid peroxidase antibodies (TPOAb), and subclinical thyroid dysfunctions in middle-aged and older adults.

Materials and methods

Cross-sectional analyses included a self-reported medical diagnosis of psoriasis and thyroid function from the 3rd visit (2017-2019) of the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil). TSH, FT4, and FT3 levels were analyzed as continuous variables and quintiles, and TPOAb positivity and subclinical hypothyroidism as a yes/no variable. Logistic regression models were built as crude and adjusted by main confounders (age, sex, education level, race/ethnicity, and smoking).

Results

From 9,649 participants (52.3% women; 59.2 ± 8.7 years old), the prevalence of psoriasis was 2.8% (n = 270). TSH, FT4, TPOAb positivity, and subclinical hypothyroidism were not associated with psoriasis in the main analyses. In the stratified analysis, our findings showed positive associations of the lowest (OR = 2.01; 95% CI 1.05-3.84; p = 0.036) and the highest (OR = 2.13; 95% CI 1.12-4.05; p = 0.022) quintiles of FT4 and a protective association of TPOAb positivity (OR = 0.43; 95% CI 0.19-0.98; p = 0.046) with prevalent psoriasis in women. In the logistic regression for FT3, participants in the 1st quintile showed a statistically significant association with psoriasis for the whole sample (OR = 1.66; 95% CI 1.11-2.46; p = 0.013) and for men (OR = 2.25; 95% CI 1.25-4.04; p = 0.007) in the sex-stratified analysis.

Conclusions

The present study showed that the association of FT4 levels with psoriasis are different according to sex, with a possible U-shaped curve in women but not in men. Although there were some associations of FT3 with psoriasis, they may be a consequence of non-thyroidal illness syndrome. Further prospective data may clarify the association of thyroid function and psoriasis.

Type 3 autoimmune polyglandular syndrome (APS-3) or type 3 multiple autoimmune syndrome (MAS-3): an expanding galaxy

BACKGROUND

The number of recognised distinct autoimmune diseases (AIDs) has progressively increased over the years with more than 100 being reported today. The natural history of AIDs is characterized by progression from latent and subclinical to clinical stages and is associated with the presence of the specific circulating autoantibodies. Once presented, AIDs are generally chronic conditions. AIDs have the tendency to cluster and co-occur in a single patient. Autoimmune thyroid diseases (AITD) are the most prevalent of AIDs in the world population, and about one-third of the AITD patients also present with a non-thyroid AID during their life-span. Furthermore, patient with non-thyroid AIDs often presents with a form of AITD as a concurrent condition. Many of the clusters of AIDs are well characterized as distinctive syndromes, while some are infrequent and only described in case reports.

PURPOSE

In this review, we describe the wide spectrum of the combinations and the intricate relationships between AITD and the other AIDs, excluding Addison's disease. These combinations are collectively termed type 3 Autoimmune Polyglandular Syndrome (APS-3), also called type 3 Multiple Autoimmune Syndrome (MAS-3), and represent the most frequent APS in the world populations.

CONCLUSIONS

Numerous associations of AITD with various AIDs could be viewed as if the other AIDs were gravitating like satellites around AITD located in the center of a progressively expanding galaxy of autoimmunity.

Conundrum for Psoriasis and Thyroid Involvement

Strategies concerning thyroid anomalies in patients confirmed with psoriasis, either on clinical level or molecular levels, and their genetic findings remain an open issue. Identification of the exact subgroup of individuals that are candidates to endocrine assessments is also controversial. Our purpose in this work was to overview clinical and pathogenic data concerning psoriasis and thyroid comorbidities from a dual perspective (dermatologic and endocrine). This was a narrative review of English literature between January 2016 and January 2023. We included clinically relevant, original articles with different levels of statistical evidence published on PubMed. We followed four clusters of conditions: thyroid dysfunction, autoimmunity, thyroid cancer, and subacute thyroiditis. A new piece of information in this field was the fact that psoriasis and autoimmune thyroid diseases (ATD) have been shown to be related to the immune-based side effects of modern anticancer drugs-namely, immune checkpoint inhibitors (ICP). Overall, we identified 16 confirmatory studies, but with heterogeneous data. Psoriatic arthritis had a higher risk of positive antithyroperoxidase antibodies (TPOAb) (25%) compared to cutaneous psoriasis or control. There was an increased risk of thyroid dysfunction versus control, and hypothyroidism was the most frequent type of dysfunction (subclinical rather than clinical), among thyroid anomalies correlated with >2-year disease duration, peripheral > axial and polyarticular involvement. With a few exceptions, there was a female predominance. Hormonal imbalance included, most frequently, low thyroxine (T4) and/or triiodothyronine (T3) with normal thyroid stimulating hormone (TSH), followed by high TSH (only one study had higher total T3). The highest ratio of thyroid involvement concerning dermatologic subtypes was 59% for erythrodermic psoriasis. Most studies found no correlation between thyroid anomalies and psoriasis severity. Statistically significant odds ratios were as follows: hypothyroidism: 1.34-1.38; hyperthyroidism: 1.17-1.32 (fewer studies than hypo); ATD: 1.42-2.05; Hashimoto's thyroiditis (HT): 1.47-2.09; Graves' disease: 1.26-1.38 (fewer studies than HT). A total of 8 studies had inconsistent or no correlations, while the lowest rate of thyroid involvement was 8% (uncontrolled studies). Other data included 3 studies on patients with ATD looking for psoriasis, as well as 1 study on psoriasis and thyroid cancer. ICP was shown to potentially exacerbate prior ATD and psoriasis or to induce them both de novo (5 studies). At the case report level, data showed subacute thyroiditis due to biological medication (ustekinumab, adalimumab, infliximab). Thyroid involvement in patients with psoriasis thus remained puzzling. We observed significant data that confirmed a higher risk of identifying positive antibodies and/or thyroid dysfunction, especially hypothyroidism, in these subjects. Awareness will be necessary to improve overall outcomes. The exact profile of individuals diagnosed with psoriasis who should be screened by the endocrinology team is still a matter of debate, in terms of dermatological subtype, disease duration, activity, and other synchronous (especially autoimmune) conditions.

Risk of cancer in Korean patients with psoriatic arthritis: a nationwide population-based cohort study

OBJECTIVE

While many studies on the increased risk of cancer in patients with psoriasis are available, data on the risk of cancer in patients with psoriatic arthritis (PsA) are still scarce. We assessed the risk of cancer in patients with PsA in a nationwide population-based cohort in Korea.

METHODS

From 2010 to June 2021, patients newly diagnosed with PsA and 1:10 age-matched and sex-matched controls were included in this study. The outcome was the incidence of overall and specific cancers.

RESULTS

Total 162 cancers occurred in 4688 PsA patients (incidence rate 83.2 (95% CI 70.8 to 97.0) per 10 000 person-years) and 1307 cancers occurred in 46 880 controls (incidence rate 66.9 (95% CI 63.3 to 70.6) per 10 000 person-years). The adjusted HR (aHR) of overall cancer in PsA patients was 1.20 (95% CI 1.02 to 1.41). However, this significance disappeared when non-melanoma skin cancer (NMSC) was excluded (aHR 1.16, 95% CI 0.98 to 1.37). Among specific cancers, the risk of NMSC (aHR 3.64 (95% CI 1.61 to 8.23)), lymphoma (aHR 2.63 (95% CI 1.30 to 5.30)) and thyroid cancer (aHR 1.83 (95% CI 1.18 to 2.85)) was higher in patients with PsA than in controls.

CONCLUSION

The risk of overall cancer was higher in patients with PsA than in the general population. Patients with PsA had increased risks of NMSC, lymphoma and thyroid cancer compared with the general population. Our findings suggest a need to conduct cancer screening by a detailed history and comprehensive clinical examination in patients with PsA.

Consensus statements for pharmacological management, monitoring of therapies, and comorbidity management of psoriatic arthritis in the United Arab Emirates

OBJECTIVE

Psoriatic arthritis (PsA), a chronic inflammatory disease characterized by heterogeneous clinical manifestations, substantially impacts the quality of life of affected individuals. This article aims at developing consensus recommendations for the management of PsA and associated comorbidities and screening and monitoring requirements of PsA therapies in the United Arab Emirates (UAE) population.

METHODS

An extensive review of present international and regional guidelines and publications on the pharmacological management, monitoring of therapies in the context of PsA was performed. Key findings from guidelines and literature were reviewed by a panel of experts from the UAE at several meetings to align with current clinical practices. Consensus statements were formulated based on collective agreement of the experts and members of Emirates Society for Rheumatology.

RESULTS

The consensus recommendations were developed to aid practitioners in clinical decision-making with respect to dosage recommendations for pharmacological therapies for PsA, including conventional drugs, non-biologic, and biologic therapies. Consensus recommendations for therapeutic options for the treatment of PsA domains, including peripheral arthritis, axial disease, enthesitis, dactylitis, psoriasis, and nail disease, were developed. The panel emphasized the importance of monitoring PsA therapies and arrived at a consensus on monitoring requirements for PsA therapies. The expert panel proposed recommendations for the management of common comorbidities associated with PsA.

CONCLUSION

These consensus recommendations can guide physicians and healthcare professionals in the UAE in making proper treatment decisions, as well as efficiently managing comorbidities and monitoring therapies in patients with PsA.

Prevalence of autoimmune thyroid disease in patients with psoriasis: a meta-analysis

OBJECTIVE

Psoriasis is a chronic inflammatory disease with autoimmune aetiology. A possible link between psoriasis and autoimmune thyroid disease (AITD) has been suggested in some studies with inconsistent findings. This meta-analysis aims to determine the association between psoriasis and AITD.

DESIGN

A meta-analysis of observational studies.

DATA SOURCES

PubMed, EMBASE, Scopus and the Cochrane Library were searched up to 1 November 2021.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

We included non-randomised studies, each with over 50 cases in every group, focusing on the rate of comorbidity between psoriasis and AITD.

DATA EXTRACTION AND SYNTHESIS

Two independent reviewers screened the articles and extracted data. The restricted maximum-likelihood was applied to perform the meta-analysis. OR and 95% CIs were pooled to compare the prevalence of AITD in psoriasis and control groups. Heterogeneity was assessed with I² statistic. The Newcastle-Ottawa Scale and Agency for Healthcare Research and Quality were applied for quality assessment. The risk of bias was assessed with Risk Of Bias In Non-randomised Studies-of Interventions (ROBINS-I).

RESULTS

Eleven available studies with data on 253 313 patients with psoriasis and 1 376 533 controls were included. Meta-analysis showed that patients with psoriasis had a higher prevalence of AITD (OR 1.76, 95% CI 1.35 to 2.28, Z=4.25, p<0.01), especially loss-of-function disorder of the thyroid gland. Both thyroglobulin antibodies positive rate (OR 1.98, 95% CI 1.27 to 3.10, Z=3.00, p<0.01) and thyroid peroxidase antibodies positive rate (OR 2.15, 95% CI 1.31 to 3.52, Z=3.05, p<0.01) were also increased in the psoriasis group compared with the control group.

CONCLUSIONS

Our study indicates that the rate of co-occurring AITD was significantly increased in patients with psoriasis. It suggests that the increased risk of AITD should be concerned in patients with psoriasis.

PROSPERO REGISTRATION NUMBER

CRD42020206005.

Relationship between autoimmune thyroid disease and nephropathy: A clinicopathological study

The association of nephropathy with autoimmune thyroid disease (AITD) has been reported previously. However, there is limited information on the relationship between thyroid autoantibodies and nephropathy. A retrospective study was conducted using the medical records of 246 patients with nephropathy, 82 of whom had concurrent AITD. General characteristics, thyroid function, autoantibodies, and the pathological types of nephropathy were analyzed. Immunohistochemistry was used to detect the thyroglobulin antibody (TG-Ab) and thyroid peroxidase antibody (TPO-Ab) in the kidneys. We found nephropathy patients with AITD exhibited higher serum levels of TPO-Ab, TG-Ab, thyroid-stimulating hormone receptor antibody (TR-Ab), and immunoglobulin G (IgG) (P < .05). Compared with the nephropathy without AITD group, the nephropathy with AITD group exhibited higher proportions of membranous nephropathy (MN) and focal segmental glomerulosclerosis (FSGS), and relatively lower proportions of mesangial proliferative glomerulonephritis (MsPGN) and minimal change nephropathy (MCN) (P = .005). TPO-Ab and TG-Ab levels in the kidney were more prevalent in nephropathy patients with AITD than those without AITD (P = .015 and P = .026, respectively). Subgroup analysis demonstrated that serum levels of thyroid stimulating hormone (TSH), TG-Ab, TPO-Ab, immunoglobulin M (IgM), and IgG in the MN group were significantly higher, whereas the levels of free thyroxine (FT4) and estimated glomerular filtration rate (eGFR) were lower, as compared with MN with Hashimoto thyroiditis (HT) group (P < .05). TPO-Ab and TG-Ab expression levels in the kidneys were more prevalent in the MN group than in the MN with HT group (P = .034). The expression levels of FT4, TG-Ab, TPO-Ab, and thyroid-stimulating hormone receptor antibody (TSHR-Ab) in the serum were significantly higher in the MN group than in the MN with Graves disease (GD) group (P < .05). The expression of TPO-Ab in the kidneys was more prevalent in the MN group than in the MN with GD group (P = .011). In sum, the expressions of TPO-Ab and TG-Ab were more prevalent in the kidneys of patients with nephropathy and AITD. Our findings indicate that TPO-Ab and TG-Ab may play a role in the development of AITD-related nephropathy.

Etiological Association Between Psoriasis and Thyroid Diseases

Psoriasis is a chronic relapsing/remitting autoimmune disease affecting skin and fingernails. It is associated with many other autoimmune diseases such as rheumatoid arthritis, celiac disease, Crohn's disease, and thyroid diseases. Two important autoimmune thyroid diseases - Hashimoto's thyroiditis (hypothyroidism) and Grave's disease (hyperthyroidism) - affect the body's significant organs such as the brain, muscles, digestive function, and the skin. Although some studies have established the connection between psoriasis and thyroid diseases with autoimmunity, our article provides an in-depth analysis of the connection between these two diseases and other common etiological factors associated with them, along with autoimmunity.

We reviewed articles from PubMed using regular keywords and Medical Subject Headings (MeSH) keywords and finalized 45 articles to find an association between these two diseases. These articles showed that this association is more prevalent in obese patients and late-onset psoriasis. Most of the articles showed a positive association, but few articles showed no connection between them. However, there is no concrete explanation to prove the association due to limited research; additional studies are necessary. It requires the attention of both clinicians and researchers to develop a universal drug that will work on both diseases, and also thyroid evaluation could be included in psoriatic patient care so that there is a possibility to decrease cost and efforts while treating these diseases. 

The Risk of Systemic Diseases in Those with Psoriasis and Psoriatic Arthritis: From Mechanisms to Clinic

Psoriasis and psoriatic arthritis (PsA) have been recently considered as chronic systemic inflammatory disorders. Over the past decades, enormous evidence indicates that patients with psoriasis and PsA have a higher risk of developing various comorbidities including cardiovascular disease, metabolic disease, cancers, infections, autoimmune disease, and psychiatric diseases. However, reported risks of some comorbidities in those with psoriasis and PsA are somewhat different according to the research design. Moreover, pathomechanisms underlying comorbidities of those with psoriasis and PsA remain poorly elucidated. The purpose of this review is to provide the most updated comprehensive view of the risk of systemic comorbidities in those with psoriasis and PsA. Molecular mechanisms associated with the development of various comorbidities in those with psoriasis and PsA are also reviewed based on recent laboratory and clinical investigations. Identifying the risk of systemic comorbidities and its associated pathomechanisms in those with psoriasis and PsA could provide a sufficient basis to use a multi-disciplinary approach for treating patients with psoriasis and PsA.

Not your average joint: Towards precision medicine in psoriatic arthritis

Precision medicine, propelled by advances in multi-omics methods and analytics, aims to revolutionize patient care by using clinically-actionable molecular markers to guide diagnostic and therapeutic decisions. We describe the applications of precision medicine in risk stratification, drug selection, and treatment response prediction in psoriatic arthritis, for which targeted, personalized approaches are steadily emerging.

Safety Profile of Biologics Used in Rheumatology: An Italian Prospective Pharmacovigilance Study

Post-marketing surveillance activities are essential to detect the risk/benefit profile of biologic disease-modifying antirheumatic drugs (bDMARDs) in inflammatory arthritis. The aim of this study was to evaluate adverse events (AEs) in patients treated with bDMARDs in rheumatology during a prospective pharmacovigilance study from 2016 to 2018. Descriptive statistical analyses were performed to evaluate bDMARDs-related variables of patients without AEs/failures vs patients with AEs and failures. The risk profile among biologics was assessed by comparing patients treated with each bDMARD to patients treated with etanercept. A total of 1155 patients were enrolled, mostly affected by rheumatoid arthritis (46.0%). AEs and failures were experienced by 8.7% and 23.3%, respectively. The number of comorbidities significantly influenced the onset of AEs, while anxiety-depressive, gastrointestinal disease, and fibromyalgia influenced onset of failures. The probability of developing an AE was significantly lower in patients treated with secukinumab, while the probability of developing treatment failure was significantly lower in patients treated with golimumab, secukinumab and tocilizumab. A total of 216 AEs were reported (25.5% serious), mostly regarding infections (21.8%), musculoskeletal (17.6%) and skin (16.2%) disorders. Serious AEs included neutropenia (12.7%), lymphocytosis (9.1%) and uveitis (7.3%). The obtained results revealed known AEs but real-world data should be endorsed for undetected safety concerns.

The aggregation between AITD with rheumatologic, or dermatologic, autoimmune diseases

Autoimmune thyroid diseases (AITD) are organ-specific autoimmune disorders mediated by Th1 lymphocytes, whose main clinical presentations are Hashimoto's thyroiditis (HT), or Graves' disease (GD). HT, GD, thyroid autoantibodies and thyroid dysfunctions have been shown in systemic rheumatologic diseases (as Sjögren's syndrome, systemic lupus erythematosus, rheumatoid arthritis, systemic sclerosis, or cryoglobulinemia). New associations of AITD with other autoimmune diseases are being discovered, for example with psoriatic arthritis and dermatological diseases. Several investigations suggest the importance of a shared genetic susceptibility and of environmental factors in patients with AITD and associated systemic autoimmunity. A major Th1 autoimmune response occurs in the initial, and/or active phases of organ-specific autoimmune disorders and/or systemic rheumatologic diseases with increased serum, or tissue, expressions of the Th1 chemokine CXCL10. Thyroid dysfunctions might have an important clinical impact, so a periodic thyroid screening in women with systemic or dermatological autoimmunity, overall in presence of thyroid autoantibodies is suggested.

Is There Any Association Between Psoriasis and Hashimoto's Thyroiditis?

Background

The association between psoriasis and Hashimoto’s thyroiditis has been evaluated in many retrospectives and prospective studies with varying numbers of patients and study designs. A positive association had been found certain studies, while no clear association in others.

Objective

The objective of this study was to evaluate the prevalence of Hashimoto’s thyroiditis in patients with psoriasis in comparison with healthy matched control from the same geographical region.

Methods

A case-control study was conducted from October 2017 to October 2018 in Faiha Specialized Diabetes, Endocrine, and Metabolism Center (FDEMC). Fifty-six psoriatic patients were compared with 54 healthy, gender, age and body mass index-matched controls. All participants had thyroid evaluation in the form of measurement of thyroid-stimulating hormone (TSH), free thyroxine (FT4), antithyroid peroxidase antibody (TPO Ab), and antithyroglobulin antibody (Tg Ab). Thyroid ultrasound examination was performed looking for volume, hypo-echogenicity, pseudo-nodularity, and increased vascularity. Assessment of psoriasis severity was conducted using the Psoriasis Area and Severity Index (PASI) score.

Results

Significantly higher prevalence of TPO Ab, Tg Ab, hypo-echogenicity, pseudo-nodularity, and increased vascularity was found in patients with psoriasis. The prevalence in psoriasis versus control was for TPO Ab (25.0% vs 9.3%, p = 0.02), Tg Ab (30.4% vs 11.1%, p = 0.01), hypo-echogenicity (30.4% vs 9.3%, p = 0.02), pseudo-nodularity (16.1% vs 0%, p = 0.002), and increased vascularity (35.7% vs 5.6%, p = 0.001). Patients with psoriasis with age of onset at diagnosis ≥40 years old and obesity were significantly more likely to have positive TPO Ab with a prevalence of (42.1% and 40.7%, respectively). There were no significant differences in the prevalence of hypothyroidism and subclinical hypothyroidism between psoriasis and control. In patients with psoriasis, psoriasis types, severity, duration, age, gender, smoking status, type 2 diabetes, and personal and family history of autoimmune diseases did not correlate with thyroid autoimmunity.

Conclusions

This study demonstrates a clear association between psoriasis and Hashimoto’s thyroiditis in the form of a significantly higher prevalence of TPO Ab, Tg Ab, hypo-echogenicity, pseudo-nodularity, and increased vascularity. Hence, thyroid evaluation by anti-thyroid antibodies, particularly TPO Ab, and ultrasound should be included in the care of psoriasis patients.

Rheumatoid arthritis and thyroid dysfunction: A cross-sectional study and a review of the literature

Thyroid dysfunction appears to show increased prevalence in many autoimmune diseases; however, this comorbidity has not been properly investigated in patients with RA. This issue was addressed in this cross-sectional study. Using the database of the Clalit Health Services (CHS) in Israel, RA patients were paired with age- and sex-matched controls to compare the prevalence of hypothyroidism and hyperthyroidism. Chi-squared and t-tests were used for univariate analysis and a logistic regression model was used for multivariate analysis. The study included 11,782 patients with RA and 57,973 controls. The rate of thyroid dysfunction diseases in RA patients was increased compared with the prevalence in controls (16.0% and 11.7%, p < 0.001, for hypothyroidism; and 2.33% and 1.81%, p < 0.001 in hyperthyroidism, respectively). In a multivariate analysis, RA was associated with hypothyroidism (OR = 1.42, 95% CI 1.34-1.50) and hyperthyroidism (OR = 1.26, 95% CI 1.10-1.45). RA is associated with thyroid dysfunction. Therefore, physicians treating patients with RA should be aware of the possibility of comorbid thyroid dysfunction and treat accordingly.

Psoriasis, Psoriatic Arthritis, and Thyroid Autoimmunity

Psoriasis (PsO) is a chronic relapsing/remitting autoimmune skin disease, associated with an increased risk of other autoimmune disorders. Psoriatic arthritis (PsA) is a chronic inflammatory arthritis occurring approximately in 30% of PsO patients. Sporadic cases of association between PsO and autoimmune thyroid disorders (AITDs) have been reported. However, two different recent studies did not find any association between them. In patients with PsO and PsA, an association with AITD has been shown by most of the studies in adults, but not in the juvenile form. In PsA women and men, thyroid autoimmunity [positive antithyroid peroxidase (AbTPO) antibodies, hypoechoic thyroid pattern] and subclinical hypothyroidism were more prevalent than in the general population. An association has been shown also in patients with PsO, arthritis, and inflammatory bowel disease, who have more frequently AITD. A Th1 immune predominance has been shown in early PsO, and PsA, with high serum CXCL10 (Th1 prototype chemokine), overall in the presence of autoimmune thyroiditis. This Th1 immune predominance might be the immunopathogenetic base of the association of these disorders. A raised incidence of new cases of hypothyroidism, thyroid dysfunction, positive AbTPO, and appearance of a hypoechoic thyroid pattern in PsA patients, especially in women, has been shown recently, suggesting to evaluate AbTPO levels, thyroid function, and thyroid ultrasound, especially in PsA women. Thyroid function follow-up and suitable treatments should be performed regularly in PsA female patients at high risk (thyroid-stimulating hormone within the normal range but at the higher limit, positive AbTPO, hypoechoic, and small thyroid).