Epidemiology and clinical pattern of psoriatic arthritis in Germany: a prospective interdisciplinary epidemiological study of 1511 patients with plaque-type psoriasis

How can psoriatic arthritis be diagnosed early?

Psoriatic arthritis (PsA) is an inflammatory arthritis that usually develops after the onset of cutaneous psoriasis. Early diagnosis of PsA may lead to less joint damage and better long-term outcomes. Identifying inflammatory arthritis in individuals with psoriasis is the key to early diagnosis of PsA. Screening strategies targeted at individuals with psoriasis, as well as family members of patients with PsA will result in early identification of PsA. This article describes the various strategies that could be employed to identify inflammatory arthritis in patients with psoriasis so that appropriate referral to a rheumatologist for early diagnosis of PsA may be made.

Arthritis as an important determinant for psoriatic patients to develop severe vascular events in Taiwan: a nation-wide study

BACKGROUND

Psoriasis is an important systemic inflammatory disease that often leads to severe vascular diseases. This study was launched to determine if joint involvement affects incidence of vascular comorbidities in psoriatic patients. In addition, potential vasculo-protective effects of methotrexate in psoriatic patients were also evaluated.

METHOD

A population-based retrospective cohort study was conducted using the Taiwanese National Health Insurance database spanning from 1996 to 2006. Accordingly, 7648 and 284 psoriatic patients without or with arthritis, respectively, were identified. To ensure the temporal relationship between different events, those with date of first diagnosis psoriasis during the year of 1996 were excluded from subsequent analyses. In addition, those with diagnosis of cerebrovascular or cardiovascular diseases prior to onset of psoriasis were also excluded from relevant subsequent analyses.

RESULT

Taking psoriatic patients without arthritis as the referent group, the hazard ratio for incident cerebrovascular disease was 1.82 (95% CI = 1.17-2.82) for psoriatic patient with arthritis. In addition, psoriatic patients without arthritis who had methotrexate treatment showed reduced risks for incident cerebrovascular disease as compared with those with no arthritis and had received no methotrexate/retinoid treatment. Similar analyses were performed on cardiovascular diseases, and equivalent results were obtained.

CONCLUSION

Our study indicated that arthritis is a potential determinant for psoriatic patients in terms of incident vascular comorbidities. In addition, methotrexate treatment may be associated with reduced risks for development of severe vascular diseases in psoriatic patients without arthritis. Further studies should focus on the clinical complications associated with psoriatic patients with or without arthritis.

S3 - Guidelines on the treatment of psoriasis vulgaris (English version). Update

Psoriasis vulgaris is a common and often chronic inflammatory skin disease. The incidence of psoriasis in Western industrialized countries ranges from 1.5% to 2%. Patients afflicted with severe psoriasis vulgaris may experience a significant reduction in quality of life. Despite the large variety of treatment options available, surveys have shown that patients still do not received optimal treatments. To optimize the treatment of psoriasis in Germany, the Deutsche Dermatologi sche Gesellschaft (DDG) and the Berufsverband Deutscher Dermatologen (BVDD) have initiated a project to develop evidence-based guidelines for the management of psoriasis. They were first published in 2006 and updated in 2011. The Guidelines focus on induction therapy in cases of mild, moderate and severe plaque-type psoriasis in adults including systemic therapy, UV therapy and topical therapies. The therapeutic recommendations were developed based on the results of a systematic literature search and were finalized during a consensus meeting using structured consensus methods (nominal group process).

Early psoriatic arthritis

Psoriatic arthritis is an inflammatory musculoskeletal disease associated with psoriasis that is usually seronegative for rheumatoid factor. Psoriatic arthritis affects men and women equally, usually during the fourth decade, although it may affect children and octogenarians. Psoriatic arthritis may lead to deformities, joint damage, reduced quality of life and function. Early detection and treatment may prevent untoward outcomes.

[Diagnosis and therapy of early psoriatic arthritis]

Early diagnosis of psoriatic arthritis is of importance because an erosive disease is already detectable after a 2-year duration of symptoms. Often psoriatic arthritis cannot easily be detected because of the diversity of disease manifestations in early stages. As up to 30% of psoriasis patients develop psoriatic arthritis an interdisciplinary dermatologic/rheumatologic approach to diagnose findings and treatment decisions would be desirable. Screening tools, such as validated questionnaires allow an early detection and selection of patients with a high probability of psoriatic arthritis even in dermatological care or on a house physician basis. The implementation of the CASPAR criteria as a classification tool for psoriatic arthritis has also improved the diagnosis finding in patients with a recent onset of active musculoskeletal disease. Data from early psoriatic arthritis cohorts illustrate that drug-free remission is rare. An adequate treatment is of importance. The Group for Research and Assessment of Psoriasis and Psoriatic Arthritis (GRAPPA) has developed treatment recommendations based on the available evidence for different treatment modalities.

[Psoriasis arthritis. An interdisciplinary challenge]

Psoriatic arthritis (PsA) is classified as a spondylarthropathy based on its clinical and serological characteristics. The clinical manifestations and the association with psoriasis or nail psoriasis have led, together with immunological characteristics, to a further differentiation. The pathophysiological and genetic understanding of this disease has advanced as a result of the development of new treatment strategies and targets in rheumatology and dermatology. Collaborative efforts and increasing multidisciplinary cooperation between rheumatologists and dermatologists have led to an increased awareness in early diagnosis and treatment. New treatment modalities have demonstrated significant efficacy in preventing radiologic progression resulting in amelioration of clinical symptoms, improvement of function and quality of life.

Adalimumab monotherapy in a patient with psoriatic arthritis associated with chronic renal failure on hemodialysis: a case report and literature review

We report a patient with psoriatic arthritis (PsA) who was successfully treated with adalimumab even while under hemodialysis therapy for associated chronic renal failure. Flow cytometry of circulating lymphocytes revealed an obvious decrease in both Th1 and Th17 cells after starting adalimumab. The latter returned to the pretreatment level in the course of adalimumab therapy, while the former did not. Adalimumab is a potent therapeutic option for PsA patients with chronic renal failure on hemodialysis, and Th1 in peripheral blood may reflect the disease activity.

Prevalence of eye disease in Brazilian patients with psoriatic arthritis

OBJECTIVES

The aim of this study was to report the type and frequency of ocular manifestations in Brazilian psoriatic arthritis patients.

METHODS

We conducted a cross-sectional study in a Brazilian tertiary hospital. The test group included 40 patients who had psoriatic arthritis according to the Classification Criteria for Psoriatic Arthritis. A control group of 40 individuals was matched for age and gender. All of the patients underwent ophthalmic evaluation, which included best-corrected visual acuity, slit lamp and fundus examinations, and dry eye diagnostic tests (Schirmer I, tear breakup time and rose bengal). Demographic parameters were also evaluated.

RESULTS

The mean age of the patients was 53.9±13.1 years; the mean disease duration was 8±10.5 years. Most of the patients were women (60%), and the majority had polyarticular disease (57.5%). Several ocular abnormalities were found, including punctate keratitis, pinguecula, blepharitis, pterygium, cataract, glaucoma, uveitis, and retinal microvascular abnormalities. There were no significant differences in the rates of these abnormalities compared with the control group, however. The Keratoconjunctivitis sicca and dry eye diagnostic tests were more often positive in the patients with psoriatic arthritis than in the control group.

CONCLUSIONS

In this study, keratoconjunctivitis sicca was the most common ocular finding related to psoriatic arthritis. Therefore, we recommend early ophthalmologic evaluations for all psoriatic arthritis patients who complain of eye symptoms.

[Psoriatic arthritis : a permanent challenge for rheumatologists and patients--Part 1: epidemiology, pathogenesis and clinical course]

Psoriatic arthritis is still one of the big challenges in rheumatology due to the great variety of symptoms. Treatment frequently requires an interdisciplinary collaboration of general practitioners, dermatologists and rheumatologists who are able to recognize the onset of disease early by means of classification criteria and new imaging techniques followed by the implementation of appropriate antirheumatic treatment. During recent years new immunological pathways have been discovered leading to an increasing number of potential therapies, which increases the chance to find effective individualized treatment. However, tracking back the onset of the disease to specific causes is still a challenge which is made even more complex due to the absence of specific serum parameters.

Strategies for improving the quality of care in psoriasis with the use of treatment goals--a report on an implementation meeting

Targeted treatment, early intervention and the use of treatment goals is a new approach in medicine that has been implemented across several disciplines (e.g. diabetes, pulmonary arterial hypertension and rheumatoid arthritis) over the last 5-10 years. As in other chronic diseases, well-defined treatment goals may be helpful in guiding physicians in their care of patients with psoriasis, thereby obviating poor outcomes. Individual treatment goals were recently developed for the first time in psoriasis by a European Consensus group of experts from 19 European countries to supplement guidelines and promote the consistent use of available therapies to improve patient care. Goal-oriented therapy involves treating according to a treatment algorithm, regularly monitoring therapeutic response and prompt modification of therapy if goals are not met. In the absence of hard outcomes in psoriasis (e.g. biomarkers or biomedical predictors of clinical response), the European Consensus group based their treatment goals on changes in Psoriasis Area Severity Index and Dermatology Life Quality Index scores. Further evidence generation is important to determine whether surrogate markers for disease progression (e.g. co-morbidities) or predictors of clinical response can be identified for psoriasis. Furthermore, psoriasis may have a potential cumulative effect on the life course of patients, the understanding of which is likely to provide the rationale for earlier treatment strategies in psoriasis. For the work of the European Consensus group to have an impact on clinical care, transmission of treatment goals into guidelines, along with implementation of treatment goals at both the regional and national level is needed. Thus, dermatology experts from Europe, the Middle East, Australia and Canada gathered in Frankfurt, 2010, for a 1.5 day educational meeting run by the Progressive Psoriasis Initiative to discuss how treatment goals in psoriasis might best be implemented in clinical practice. The meeting conclusions are presented here.

Psoriatic arthritis: a systematic review

Psoriatic arthritis is an inflammatory rheumatic disorder of unknown etiology occurring in patients with psoriasis. The Classification Criteria for Psoriatic Arthritis study group has recently developed a validated set of classification criteria for psoriatic arthritis with a sensitivity of 91.4% and a specificity of 98.7%. Three main clinical patterns have been identified: oligoarticular (≤ 4 involved joints) or polyarticular (≥ 5 involved joints) peripheral disease and axial disease with or without associated peripheral arthritis. In this context distal interphalangeal arthritis and arthritis mutilans may occur. According to other reports, also in our centre, asymmetric oligoarthritis is the most frequent pattern at onset. Axial disease has been estimated between 5% and 36% of patients. It is characterized by an irregular involvement of the axial skeleton with a predilection for the cervical spine. Recurrent episodes of enthesitis and dactylitis represent a hallmark of psoriatic arthritis. In around 20% of cases distal extremity swelling with pitting edema of the hands or feet is observed. Unilateral acute iridocyclitis, usually recurrent in alternate fashion, is the most frequent extra-articular manifestation, and accelerated atherosclerosis is the prominent comorbidity. The clinical course of peripheral and axial psoriatic arthritis is usually less severe than rheumatoid arthritis and ankylosing spondylitis, respectively. Local corticosteroid injections and non-steroidal anti-inflammatory drugs are recommended in milder forms. Sulphasalazine and methotrexate are effective in peripheral psoriatic arthritis. Recent studies have provided evidence on the efficacy of anti-tumor necrosis factor-α drugs to control symptoms and to slow or arrest radiological disease progression.

[Health services research in dermatology. Current status]

Assessment of benefits and quality of medical healthcare treatment is becoming more and more important. In order to accurately carry out this assessment and to assure a reliable planning of health care, valid data are needed. Health services research is an interdisciplinary field of research, which provides information on disease and health care and to uncover suboptimal and incorrect services. This information can be used to improve the quality of treatment and to increase efficiency. In order to obtain information on the health care for skin and allergic diseases the German Center for Health Services in Dermatology (CVderm) was founded in 2005. It is actively involved in the coordination and conducation of health care, collaborating with other university groups.

Prevalence and characteristics of psoriatic arthritis in Chinese patients with psoriasis

BACKGROUND

The prevalence and clinical characteristics of psoriatic arthritis (PsA) in patients with psoriasis vary widely in different countries and studies on Chinese population are rarely reported.

OBJECTIVE

The aim of this study was to evaluate the prevalence and clinical characteristics of PsA in a Chinese population of patients with psoriasis.

METHODS

A large cross-sectional observational study was conducted in our outpatient dermatology department and consecutive psoriatic patients were evaluated for PsA according to Classification of Psoriatic arthritis (CASPAR) criteria. Demographic and medical parameters were recorded.

RESULTS

Among 1928 patients with psoriasis, 112 patients (5.8%) had PsA, of which 92% was newly diagnosed. Oligoarthritis (48.2%) was the most common manifestation pattern, followed by spondylitis (26.8%), polyarthritis (19.6%) and classic distal interphalangeal (DIP) arthritis (5.4%). Enthesitis was present in 26.8% and dactylitis in 13.4% of the patients. Compared with patients without PsA, patients with PsA had more severe skin disease (mean PASI 9.7 vs. 6.0), higher frequency of nail changes (46.4% vs. 21.0%) and scalp involvement (90.2% vs. 76.4%).

CONCLUSION

The findings are consistent with a low prevalence of PsA among patients with psoriasis in Asia and confirm a high percentage of undiagnosed cases with active arthritis among PsA patients in dermatologist's office. Dermatologists should screen for PsA in their patients, especially those with risk characteristics and early signs.

Antigens from Leishmania amastigotes inducing clinical remission of psoriatic arthritis

A first generation vaccine (AS100-1) was manufactured with protein from four cultured Leishmania species, which proved to be effective in the treatment of psoriasis. A single blind trial on 3,132 psoriasis patients revealed 508 (16.2%) subjects with psoriatic arthritis (PsA) that received AS100-1 antigens. The study group was distributed according to percent psoriasis area and severity index (PASI) reduction from PASI 10 to PASI 100. All groups decreased in arthritis score (AS), tender joints counts and nail changes after treatment; the highest decreased in the PASI 100 group. Relapses of psoriasis and PsA had PASI and AS lower than initial values before treatment. Clinical remissions were at lower doses and less time, after the second course of treatment. Peripheral blood mononuclear cells (PBMC) lymphocyte subsets (LS) varied with PASI range (1-10, 11-20 and 21-72). Pre-treatment, absolute values of gated LS: CD4+, CD8+HLA-, CD8+HLA+, CD8+CD3-, CD8+CD3+ decreased in PBMC as PASI increased, suggesting migration from the blood to the skin. In contrary to the previous finding, the following LS: CD8+CD4-, CD3+CD8-, HLA+CD8-, CD19, CD8+CD4+ and membrane surface immunoglobulin IgA+, IgD+, IgM+, IgE+, and IgG+ increased in PBMC as PASI increased suggesting activation and proliferation by unknown antigens creating a homeostatic cycle between skin/joints and peripheral blood. After nine doses of AS100-1, the following LS: CD8+CD3+, CD8+HLA+, CD3+CD8-, CD4+CD8-, CD8+HLA-, HLA+CD8-, CD8+CD3-, CD19+, CD8+CD4-, CD8+CD4+, IgA+, IgD+, IgM+, IgE+, and IgG+ decreased significantly as compared with values before treatment. The LS decreased stops the vicious cycle between skin/joints and blood explaining clinical remission of lesions.

Usefulness of ultrasound imaging in detecting psoriatic arthritis of fingers and toes in patients with psoriasis

Background. Given that clinical evaluation may underestimate the joint damage and that early treatment can slow down psoriatic arthritis (PsA) progression, screening psoriasis patients with imaging tools that can depict early PsA changes would entail clear benefits. Objective. To compare the ability of X-ray and ultrasound (US) examination in detecting morphological abnormalities consistent with early PsA in patients with psoriasis, using rheumatological evaluation as the gold standard for diagnosis. Methods. Patients with chronic plaque psoriasis and no previous PsA diagnosis attending our outpatient dermatology clinic and reporting finger/toe joint and/or tendon pain underwent X-ray and US evaluation; they were subsequently referred to a rheumatologist for clinical examination and review of imaging findings. Results. Abnormal US and/or X-ray findings involving at least one finger and/or toe (joints and/or tendons) were seen in 36/52 patients: 11 had one or more X-ray abnormalities, including erosion, joint space narrowing, new bone formation, periarticular soft tissue swelling, and periarticular osteoporosis; 36 had suspicious changes on US. Conclusion. US proved valuable in detecting joint and/or tendon abnormalities in the fingers and toes of patients with suspicious changes. The dermatologist should consider US to obtain an accurate assessment of suspicious findings.

Nail psoriasis as a severity indicator: results from the PsoReal study

BACKGROUND

Although nail psoriasis affects a substantial proportion of psoriasis patients and causes significant psychologic distress, few epidemiologic data characterizing patients with nail involvement are available. The aim of this research was to elucidate differences between patients with nail psoriasis and those without any nail involvement, taking quality indicators of health care from the patient's perspective into account.

METHODS

In total, 2449 patient members of the Deutscher Psoriasis Bund, the largest patient organization for psoriasis in Germany, were interviewed in this nationwide, noninterventional, cross-sectional study. Patients with nail psoriasis were compared with patients without any nail involvement with regard to gender, age, disease duration, affected body surface area, health-related quality of life (Dermatology Life Quality Index [DLQI] ED-5D), patient-defined treatment benefit, amount of inpatient treatments, disease duration, and numbers of work days lost.

RESULTS

Data from 2449 patients with psoriasis were analyzed. Overall, 44.8% (1078) of patients were female, mean age was 57.0 ± 11.7 years, and 72.8% had nail involvement and showed higher values for affected body surface area than those without nail involvement (8.3% versus 5.6%, respectively; P < 0.004). Health-related quality of life was significantly lower in patients with nail psoriasis (DLQI 7.2 versus 5.3; ED-5D 60.1 versus 67.3), who had more days off work (9.8 versus 3.3).

CONCLUSION

Nail involvement is an important symptom of psoriasis and is associated with greater disease severity and quality of life impairment. Accordingly, management of psoriasis should include a special focus on nail involvement.

Incidence and prevalence of psoriatic arthritis in Buenos Aires, Argentina: a 6-year health management organization-based study

OBJECTIVES

Studies regarding epidemiology of PsA are lacking in Latin America. We estimated the incidence and prevalence of PsA in a University Hospital-based Health Management Organization in Buenos Aires [Hospital Italiano Medical Care Program (HIMCP)].

METHODS

POPULATION

for incidence calculation, the population at risk was all adult members of the HIMCP, with continuous affiliation for at least 1 year from January 2000 to January 2006. Each person was followed until he/she voluntarily left the HIMCP, death or finalization of the study (final dates) contributing time at risk since January 2000 or enrolment date (whichever occurred later) to that final date. Case ascertainment: medical records of all patients with the problem psoriasis and/or PsA in the HIMCP problem-oriented computer-based patient record system, or registered in rheumatologists and/or dermatologists databases, were revised. Patients fulfilling CASPAR criteria were included.

STATISTICAL ANALYSIS

incidence rate (IR) was calculated with 95% CIs. Cumulative prevalence was estimated on 1 January 2006 (denominator population ==88,112).

RESULTS

In the study period, 138,288 persons contributed a total of 558,878 person-years, of whom 35 developed PsA (IR 6.26; 95% CI 4.2, 8.3 cases per 100,000 person-years). There were 12 females: IR 3.64 (95% CI 1.6, 5.7) cases per 100,000 person-years; and 23 males: IR 10.02 (95% CI 5.9, 14.1) cases per 100,000 person-years. On 1 January 2006, 65 prevalent cases were identified: prevalence 74 (95% CI 57, 94) cases per 100,000 members.

CONCLUSIONS

The incidence and prevalence of PsA in this Latin American country was similar to that reported in other studies from Europe and the USA.

Current status and new developments in the treatment of psoriasis and psoriatic arthritis with biological agents

Psoriasis is a chronic inflammatory disease affecting 1-3% of the general population. Among psoriatic patients, 5-40% are affected by psoriatic arthritis. Due to the chronic nature of the disease, patients suffer from substantial psychological and financial burdens, thus adding to a significantly impaired quality of life. Traditional systemic therapies for psoriasis, such as methotrexate, cyclosporin A, retinoids or PUVA therapy, have a potential for long-term toxicity and may not always provide sufficient improvement of the disease. The development of novel therapies targeting key steps in the pathogenesis of psoriasis and psoriatic arthritis now provide new and efficient treatment options. Biological therapies for the treatment of psoriasis and/or psoriatic arthritis are defined by their mode of action and can be classified into three categories: the T-cell modulating agents (alefacept and efalizumab), the inhibitors of tumour necrosis factor-alpha (TNFalpha blockers, e.g. adalimumab, certolizumab, etanercept, golimumab and infliximab) and the inhibitors of interleukin (IL) 12 and IL-23 (e.g. ustekinumab and briakinumab). This article provides a brief overview of the currently approved biological agents in the European Union and of some newer agents, such as briakinumab, certolizumab and golimumab.

Assessment of risk of psoriatic arthritis in patients with plaque psoriasis: a systematic review of the literature

OBJECTIVE

The aim of this study was to determine the prevalence of psoriatic arthritis (PsA) in the patients with plaque psoriasis and to give recommendation for the diagnosis of PsA for dermatologists.

METHODS

A systematic search was performed in Pubmed, Cochrane and Embase databases. The key-words used from the Medical Searching Heading (MeSH) were: 'Psoriasis', 'Arthritis, Psoriatic', 'Uveitis' and 'Dactylitis'. We selected cross-sectional epidemiological studies written in English or French between January 1980 and October 2009.

RESULTS

The initial literature search identified 2171 references. Based on abstract reading and exclusion of studies not written in English or French, and without control group, the final selection included 20 epidemiological studies. With the eight studies using rheumatologically validated criteria, the prevalence of PsA among psoriasis patient spanned a wide range from 7% to 26%.

CONCLUSION

Psoriasis arthritis may affect up to 24% of psoriasis patients. Dermatologist should be aware of main clinical sign of PsA to promote earlier recognition and treatment of PsA.

Safety and efficacy of the tumor necrosis factor antagonists

Psoriasis is one of the most common systemic inflammatory diseases and affects the quality of life of the affected persons profoundly. Further knowledge of the pathogenesis and new biotechnological techniques have made it possible to develop new targeted therapies, such as antibodies against tumor necrosis factor (TNF)-alpha. Today, 3 TNF inhibitors, infliximab, adalimumab, and Etanercept, have been approved for the treatment of psoriasis arthritis, psoriasis, and other indications like Crohn's disease, depending on the distinct substance by the European Medicines Agency. Golimumab was approved in September 2009 for the use in psoriasis arthritis, respectively. These substances have added new effective treatment options to the therapeutic armamentarium of psoriasis. To use these new treatments for the best of our patients, it is important to know the correct application, the advantages, as well as contraindications or possible adverse effects of the substances. This article provides an update on the TNF-alpha inhibitors with emphasis on practical daily use. Most data are on the basis of high-quality studies and official guidelines, but if necessary, data from recent publications or clinical expertise have been added. In summary, with TNF inhibitors we have gained effective new treatment options showing a favorable safety profile when paying attention to safety aspects before and during therapy (screening, monitoring).

Measuring joint involvement in polyarticular psoriatic arthritis: an introduction of alternatives

OBJECTIVE

To compare the reliability of 3 different simplified joint counts with the gold standard 66 swollen/68 tender joint count (JC66/68) for assessing clinical response in patients with polyarticular psoriatic arthritis (PsA).

METHODS

The 28-joint count (JC28), in the same way that it is used in rheumatoid arthritis, and 2 measures including distal interphalangeal (DIP) joints (the 32-joint count [JC32], including all finger joints as well as wrists and knees, and 36-joint count [JC36], which additionally included elbows and ankles), were compared with the JC66/68 in 182 patients using data from the Infliximab Multinational Psoriatic Arthritis Controlled Trial 2 trial database. Pearson's correlation coefficients were calculated to compare the swollen and tender JC28, JC32, and JC36 with the corresponding results of the total JC66/68. American College of Rheumatology (ACR) responses based on the individual measures were compared, and their ability in predicting a clinical response of ACR 20% improvement (ACR20) based on the JC66/68 was assessed by calculating the area under the receiver operating characteristic curve via logistic regression and the maximum Youden indices at weeks 14 and 24.

RESULTS

All simplified joint counts were highly correlated to the standard JC66/68 both for tenderness and swelling at each individual visit (Pearson's correlation coefficients consistently >0.8, n = 182-200; P < 0.0001). Logistic regression for ACR20 response showed that area under the curve was constantly >0.91, with comparable results for Youden indices of the simplified joint counts.

CONCLUSION

All simplified joint counts considered seemed sufficiently sensitive and specific to measure clinical response in trial patients with polyarticular PsA when compared with the JC66/68, no matter whether DIP joints were included (the JC36 and JC32) or excluded (the JC28). Further research will be needed to clarify this issue.

Psoriasis: is the impairment to a patient's life cumulative?

Psoriasis is associated with significant physical and psychological burden affecting all facets of a patient's life--relationships, social activities, work and emotional wellbeing. The cumulative effect of this disability may be self-perpetuating social disconnection and failure to achieve a 'full life potential' in some patients. Health-related quality of life studies have quantified the burden of psoriasis providing predominantly cross-sectional data and point-in-time images of patients' lives rather than assessing the possible cumulative disability over a patient's lifetime. However, social and economic outcomes indicate there are likely negative impacts that accumulate over time. To capture the cumulative effect of psoriasis and its associated co-morbidities and stigma over a patient's life course, we propose the concept of 'Cumulative Life Course Impairment' (CLCI). CLCI results from an interaction between (A) the burden of stigmatization, and physical and psychological co-morbidities and (B) coping strategies and external factors. Several key aspects of the CLCI concept are supported by data similar to that used in health-related quality of life assessments. Future research should focus on (i) establishing key components of CLCI and determining the mechanisms of impairment through longitudinal or retrospective case-control studies, and (ii) assessing factors that put patients at increased risk of developing CLCI. In the future, this concept may lead to a better understanding of the overall impact of psoriasis, help identify more vulnerable patients, and facilitate more appropriate treatment decisions or earlier referrals. To our knowledge, this is a first attempt to apply and develop concepts from 'Life Course Epidemiology' to psoriasis research.

Nail psoriasis in Germany: epidemiology and burden of disease

BACKGROUND

Although nail psoriasis affects a marked proportion of patients with psoriasis and causes significant psychological stress, only few epidemiological data characterizing patients with nail involvement are available.

OBJECTIVES

To gain robust data on the epidemiology and disease burden of nail psoriasis in Germany.

METHODS

Two nationwide, noninterventional, cross-sectional studies on psoriasis health care were conducted in 2005 and 2007, involving 48 (2005) and 130 (2007) German office-based and clinic-based dermatological centres. Data of n=3531 patients with psoriasis were collected using standardized questionnaires and physical examinations by trained dermatologists. Patients with nail psoriasis were compared with patients without any nail involvement concerning sex, age, disease duration, family history, disease severity, presence of psoriatic arthritis (PsA), health-related quality of life (HRQoL), number of inpatient therapies, and days off work.

RESULTS

Nail psoriasis was diagnosed in 40·9% of the patients; prevalence was 11·2 percentage points higher in men than in women. Patients with nail involvement had a longer disease duration (21·9 vs. 18·1 years), higher disease severity (mean Psoriasis Area and Severity Index 12·7 vs. 9·3), higher frequency of PsA (26·0% vs. 12·7%), stronger impairment of HRQoL (mean Dermatology Life Quality Index 8·9 vs. 7·3), and a 2·5-fold higher rate of inpatient treatments.

CONCLUSIONS

Nail involvement is a relevant manifestation of psoriasis and is associated with a higher disease severity and quality of life impairment. Accordingly, management of psoriasis should include a special focus on nail involvement.

Geoepidemiology and environmental factors of psoriasis and psoriatic arthritis

Psoriasis and Psoriatic Arthritis (PsA) are chronic inflammatory diseases that have a major impact on health. The prevalence and incidence estimates of these two closely related diseases show ethnic and geographic variations, being generally more common in the colder north than in the tropics. In Europe the prevalence of psoriasis varies anywhere from 0.6 to 6.5%. In the USA, the estimated prevalence of diagnosed psoriasis is 3.15%. The prevalence in Africa varies depending on geographic location, being lowest in West Africa. Psoriasis is less prevalent in China and Japan than in Europe, and is entirely absent in natives of the Andean region of South America. There are fewer reports on the incidence of psoriasis, but a recent study from Rochester, USA showed an increasing trend over the last 2 decades. The prevalence of PsA also shows similar variation, being highest in people of European descent and lowest in the Japanese. Although, study methodology and case definition may explain some of the variations, genetic and environmental factors are important. Genetic epidemiologic studies have shown that both diseases have a strong genetic component. The strongest association is with HLA-Cw*06. Associations with a number of genes including IL12B and IL23R have recently been confirmed. Environmental risk factors including streptococcal pharyngitis, stressful life events, low humidity, drugs, HIV infection, trauma, smoking and obesity have been associated with psoriasis and PsA. Here we have reviewed the current literature on the epidemiology and genetics of psoriasis and PsA.