The effect of overweight and obesity on psoriasis patients in Chinese Han population: a hospital-based study

Treatment outcomes of secukinumab in adult patients with moderate-to-severe plaque psoriasis in China: A real-world multicenter retrospective study

Secukinumab is effective in treating patients with moderate-to-severe plaque psoriasis. However, most studies assessing its effectiveness in routine clinical settings in China are mostly single-center studies with a limited sample size. The objective of this study was to assess secukinumab's efficacy, treatment patterns, and characteristics in patients with moderate-to-severe plaque psoriasis. This 24-week, multicenter (n = 5) retrospective study analyzed the data of Chinese adult patients with moderate-to-severe plaque psoriasis who initiated secukinumab treatment between May 2019 and March 2020. The Psoriasis Area and Severity Index (PASI), body surface area (BSA), Investigator's Global Assessment Modified 2011 (IGA mod 2011), and Dermatology Life Quality Index (DLQI) were assessed. Dermatologists documented the treatment dosage and modification reasons. Of the 244 secukinumab-naïve patients, most were men (73.4%, 179/244) and weighed 60-90 kg (72.8%, 177/243). The mean (SD) age at secukinumab initiation was 38.1 (11.6) years, and the disease duration was 13.5 (7.9) years. Most patients (97.1%, 237/244) received secukinumab 300 mg. At weeks 4, 12, 16, and 24, the proportion of patients achieving PASI 75 (≥75% reduction from baseline) was 40.0%, 92.1%, 88.4%, and 88.9%, respectively; PASI 90 was 15.0%, 73.7%, 81.4%, and 68.3%, respectively; and PASI 100 was 8.7%, 40.8%, 58.1%, and 41.3%, respectively. During the same periods, BSA and IGA mod 2011 showed similar improvement trends. An increasing proportion of patients achieved DLQI of 0-1 (21.6%, 65.7%, 75.0%, and 80.3%, respectively). Treatment modification was highest at week 12. The average interval between two administrations after week 4 was 62.95 days. Secukinumab was highly effective in improving the PASI, IGA, BSA, and DLQI in Chinese patients with moderate-to-severe plaque psoriasis throughout the first 24 weeks. The treatment pattern for Chinese patients differs from that in the clinical guidelines.

Prevalence of psoriatic arthritis in Chinese population with psoriasis: A multicenter study conducted by experienced rheumatologists

BACKGROUND

Reports on the prevalence of psoriatic arthritis (PsA) among Chinese patients with psoriasis are very limited. This study, conducted by rheumatologists, estimated the prevalence of PsA in a large number of Chinese patients with psoriasis.

METHODS

Consecutive patients with a confirmed diagnosis of psoriasis attending nine dermatology clinics in five hospitals were recruited. All psoriasis patients were asked to complete a questionnaire comprising 16 questions to identify possible cases of PsA. All patients with one or more positive answers to the questionnaire were evaluated by two experienced rheumatologists.

RESULTS

A total of 2434 psoriasis patients, including 1561 males and 873 females, were enrolled. Both the questionnaire and rheumatologists' examinations were completed in the dermatology clinics. The results identified 252 patients with PsA, comprising 168 males and 84 females. The overall prevalence of PsA among psoriasis patients was 10.4% (95% confidence interval [95% CI], 9.1%-11.7%). By sex, the prevalence was 10.8% (95% CI, 9.2%-12.5%) for males and 9.6% (95% CI, 7.7%-11.9%) for females and there was no significant sex difference in the prevalence of PsA (P = 0.38). Of the 252 PsA patients, 125 (49.6%, 95% CI, 41.3%-59.1%) were newly diagnosed by rheumatologists. Consequently, the prevalence of undiagnosed PsA among psoriasis patients was 5.2% (95% CI, 4.4%-6.2%).

CONCLUSION

The prevalence of PsA in the Chinese population with psoriasis is about 10.4%, which is almost double that of previous reports in the Chinese population, but lower than that in Caucasians.

Discrepancy in Metabolic Syndrome between Psoriatic Arthritis and Rheumatoid Arthritis: a Direct Comparison of Two Cohorts in One Center

OBJECTIVE

We aimed to investigate the discrepancy in metabolic syndrome (MS) and cardiovascular disease (CVD) between patients with psoriatic arthritis (PsA) and those with rheumatoid arthritis (RA).

METHODS

Patients with PsA and RA were enrolled between 1 December 2018 and 31 December 2021. Data on their demographics, height, weight, waist circumference, clinical and laboratory data, and comorbidities were collected. Disease activities of patients with RA and PsA were assessed. Prevalence was estimated by dividing cases (such as MS and CVD) of PsA and RA individually. Propensity score matching and inverse probability of treatment weighting were used for further validation.

RESULTS

Consecutively, 197 patients with PsA and 279 patients with RA were enrolled in this study. Both MS [36.0% versus 23.3%, p = 0.002, OR 1.54 (1.16, 2.05)] and CVD [6.6% versus 1.1%, p = 0.001, OR 6.13 (1.77, 21.25)] were more frequently observed in patients with PsA compared with patients with RA. The frequency of abdominal obesity was also higher in patients with PsA [61.9% versus 33.0%, OR 1.87 (1.53, 2.29), p < 0.001]. After 1:1 propensity score matching for age, sex, smoking history, serum lipids, and disease activity, MS remained more common in 117 patients with PsA than in 117 patients with RA (37.6% versus 23.1%, p = 0.016) These findings remained after the inverse probability of treatment weighting in 196 patients with PsA and 288 patients with RA. A positive linear relationship between MS with disease activity was found in patients with PsA, but not in patients with RA.

CONCLUSION

Considerable discrepancies in MS and CVD were observed between patients with PsA and those with RA. The greater odds of MS and CVD emphasize the need to pay more attention to metabolic and cardiovascular conditions in patients with PsA.

Comparison of Behavioral Risk Factors and Cardiometabolic Comorbidities of Psoriatic Arthritis and Psoriasis: A Case-Control Study in Chinese Patients

Purpose

Comparison of risk factors and comorbidities could help indicate the underlying mechanisms of diseases. This study aimed to compare behavioral factors and cardiometabolic comorbidities of PsA/psoriasis versus healthy controls to implicate the similarities and differences in potential pathogenic mechanisms for further research.

Patients and Methods

A case-control study in Chinese patients with PsA or psoriasis and healthy controls was conducted. Clinical information based on patient-reported and measured outcomes were collected. Multivariable logistic regression was used to investigate the associations, in terms of adjusted odds ratios (AORs).

Results

We randomly selected 171 patients with PsA, 342 with psoriasis, and 1026 healthy controls from our database, matching by age and sex. Dyslipidemia (AOR=4.62 for PsA and 2.97 for psoriasis) and alcohol drinking (AOR=3.20 for PsA and 3.62 for psoriasis) were significantly associated with both diseases. Overweight was inversely associated with both PsA (AOR=0.46, P=0.002) and psoriasis (AOR=0.56, P=0.001), while obesity was associated with PsA (AOR=2.02, P=0.025) but not psoriasis (AOR=0.87, P=0.621). Subgroup analysis by onset age of psoriatic lesions showed that former smoking was significantly associated with early-onset psoriasis (AOR=2.44, P=0.016) but not PsA (AOR=0.59, P=0.329). Laboratory test indicated that both PsA and psoriasis were associated with altered lipid profile.

Conclusion

PsA and psoriasis in Chinese patients share common behavioral and cardiometabolic risk factors including dyslipidemia and alcohol consumption. There is a U-shape association between BMI and PsA/psoriasis.

Higher bodily adiposity, fat intake, and cholesterol serum levels are associated with higher disease activity in psoriatic arthritis patients: is there a link among fat and skin and joint involvement?

Introduction/ objectives

Assuming that there is a link between lipid and glucose metabolism and inflammation in patients with psoriatic arthritis (PsA), our aim was to evaluate the relationships among body composition measurements, food intake, and disease activity in patients with PsA.

Methods

A total of 97 patients with PsA, according to the CASPAR criteria, were included in this cross-sectional study. Body composition measurements (whole-body DXA, GE-Lunar), food intake (3-day registry) and biochemical and inflammatory serum markers were evaluated. Skin and joint disease activity were assessed by using PASI, BSA, DAS28, and minimal disease activity (MDA). The level of significance was set as p < 0.05.

Results

A higher prevalence of obesity, according to the fat mass index (FMI) (92.7%), and metabolic syndrome (MetS) (54%) were found, but no significant changes regarding lean or bone mass were found. Joint disease activity was positively correlated with total body fat (r = 0.4; p < 0.001), FMI (r = 0.33; p < 0.001), body mass index (r = 0.20; p < 0.049) and waist circumference (r = 0.27; p = 0.009). In addition, joint disease activity was negatively associated with muscle mass (r = − 0.38; p < 0.001). Skin disease activity was positively correlated with total cholesterol (r = 0.3; p = 0.003) and LDL-cholesterol (r = 0.28; p = 0.006). After multiple adjustments, patients with severe joint disease activity had higher body adiposity than patients in remission or with low disease activity. Skin disease activity was associated with higher trans-fat intake and lower omega-6 consumption.

Conclusions

Our data suggest a possible harmful link among fat (body adiposity, saturated fat consumption, LDL-cholesterol serum levels) and joint and skin disease activity in patients with PsA.

Remission in psoriatic arthritis: Definition and predictors

OBJECTIVE

To determine the frequency of remission defined by the absence of the various disease manifestations of psoriatic arthritis (PsA) and identify predictors for remission.

METHODS

Patients followed at the PsA clinic between 2000 and 2015 were included. Patients are assessed at 6- to 12-month intervals according to a standard protocol. Remission was defined as a visit that patients had no tender or swollen joints, no inflammatory back pain, no tender entheseal sites, minimal skin involvement with BSA<1%, patient pain on visual analog scale (VAS) score of <15, patient global disease activity VAS score of <20, Health Assessment Questionnaire (HAQ) score <0.5. We used imputation approach to determine remission status for visits with incomplete criteria for each patient.

RESULTS

Data from 985 patients (57% males, average age of 47.4 years) were included in this study. From 2000 to 2015, 175 (18%) patients achieved remission at least once and 92 (9%) experienced sustained remission over at least 2 consecutive visits. In a multivariate Weibull regression analysis for the time to remission, higher BMI was associated with lower chance of remission (HR = 0.96, p = 0.012), while the use of biologics increased the chance of achieving remission (HR = 1.48, p = 0.034). The effect of biologics was also significant on the chance of achieving sustained remission for 2 or more consecutive visits (HR = 1.76, p = 0.020). However, biologics were not significantly associated with sustained remission when it was defined based on 3 or more consecutive visits.

CONCLUSION

Remission occurred at least once in 18% of the patients with PsA while sustained remission occurred in 9% of the study sample. Having higher BMI would reduce the achievement of remission. The use of biologic agents increased not only the chance of remission, but also the chance of sustained remission for at least 12 months.

Association of Psoriasis With Comorbidity Development in Children With Psoriasis

Importance

Children with psoriasis are at increased risk for comorbidities. Many children with psoriasis are also overweight or obese; it is unknown whether the increased risk of comorbidities in these children is independent of obesity.

Objective

To determine the risk of elevated lipid levels (hyperlipidemia/hypertriglyceridemia), hypertension, metabolic syndrome, polycystic ovarian syndrome, diabetes, nonalcoholic liver disease, and elevated liver enzyme levels in children with and without psoriasis, after accounting for obesity.

Design, Setting, and Participants

This was a retrospective cohort study of claims data from Optum Laboratories Data Warehouse (includes 150 million privately insured and Medicare enrollees). A cohort of 29 957 children with psoriasis (affected children) and an age-, sex-, and race-matched comparator cohort of 29 957 children without psoriasis were identified and divided into 4 groups: (1) nonobese, without psoriasis (reference cohort); (2) nonobese, with psoriasis; (3) obese, without psoriasis; and (4) obese, with psoriasis.

Main Outcomes and Measures

Risk of developing comorbidities (Cox proportional hazards regression).

Results

The overall mean (SD) age of those included in the cohort was 12.0 (4.4) years, and 16 034 (53.5%) were girls. At baseline, more affected children were obese (862 [2.9%] vs 463 [1.5%]; P < .001 for all comparisons). Children with psoriasis were significantly more likely to develop each of the comorbidities than those without psoriasis (P < .01). Obesity was a strong risk factor for development of each comorbidity, even in those without psoriasis (hazard ratios [HRs] ranging from 2.26 to 18.11). The risk of comorbidities was 40% to 75% higher among nonobese children with vs without psoriasis: elevated lipid levels (HR, 1.42; 95% CI, 1.25-1.62), hypertension (HR, 1.64; 95% CI, 1.40-1.93), diabetes (HR, 1.58; 95% CI, 1.27-1.95), metabolic syndrome (HR, 1.62; 95% CI, 1.13-2.33), polycystic ovarian syndrome (HR, 1.49; 95% CI, 1.18-1.88), nonalcoholic liver disease (HR, 1.76; 95% CI, 1.16-2.65), and elevated liver enzyme levels (HR, 1.46; 95% CI, 1.27-1.67). Except for hypertension (P = .03), no significant interaction occurred between psoriasis and obesity on the risk of comorbidities.

Conclusions and Relevance

Children with psoriasis are at greater risk of developing obesity, hyperlipidemia, hypertension, diabetes, metabolic syndrome, polycystic ovarian syndrome, nonalcoholic liver disease, and elevated liver function enzyme levels than children without psoriasis. While psoriasis is a small independent risk factor for the development of these comorbidities, obesity is a much stronger contributor to comorbidity development in children with psoriasis.

Effect of weight loss on activity in psoriatic arthritis: A systematic review

OBJECTIVE

To evaluate the association between weight loss and changes in disease activity in patients with psoriatic arthritis (PsA).

METHODS

We performed a systematic review of the literature, with searches in Medline, Embase and Cochrane Central Library from inception until April 2015.

INCLUSION CRITERIA

1) randomized controlled trials (RCT); 2) PsA patients; 3) interventions were any intervention aimed at weight control; and 4) a PsA activity-related outcome measure was evaluated. Risks of bias were assessed by the Cochrane Collaboration scale.

RESULTS

Of the 215 articles identified, only 2 RCT met the inclusion criteria, 1 in abstract format. Both showed moderate risk of bias. Patients who managed to lose weight-by any method-had better results in terms of activity and inflammation. The percentage of weight loss correlated moderately with changes in inflammatory outcomes.

CONCLUSION

Weight loss in PsA could be associated with less inflammation; however, the evidence to support this is limited.

Prevalence of psoriatic arthritis in patients with psoriasis: A systematic review and meta-analysis of observational and clinical studies

BACKGROUND

Wide-ranging prevalence estimates of psoriatic arthritis (PsA) in patients with psoriasis have been reported.

OBJECTIVES

To assess the prevalence and incidence of PsA in patients with psoriasis.

METHODS

Two authors independently searched 3 databases for studies reporting on the prevalence or incidence of PsA in patients with psoriasis. A proportion meta-analysis was performed to calculate the pooled proportion estimates of PsA in patients with psoriasis.

RESULTS

A total of 266 studies examining 976,408 patients with psoriasis were included. Overall, the pooled proportion (95% confidence interval [CI]) of PsA among patients with psoriasis was 19.7% (95% CI, 18.5%-20.9%). In children and adolescents (<18 years of age), the pooled prevalence was 3.3% (95% CI, 2.1%-4.9%). The PsA prevalence was 22.7% (95% CI, 20.6%-25.0%) in European patients with psoriasis, 21.5% (95% CI, 15.4%-28.2%) in South American patients with psoriasis, 19.5% (95% CI, 17.1%-22.1%) in North American patients with psoriasis, 15.5% (95% CI, 0.009%-51.5%) in African patients with psoriasis, and 14.0% (95% CI, 95% CI, 11.7%-16.3%) in Asian patients with psoriasis. The prevalence of PsA was 23.8% (95% CI, 20.1%-27.6%) in studies in which the Classification Criteria for Psoriatic Arthritis were applied. The incidence of PsA among patients with psoriasis ranged from 0.27 to 2.7 per 100 person-years.

LIMITATIONS

Between-study heterogeneity may have affected the estimates.

CONCLUSIONS

We found that 1 in 4 patients with psoriasis have PsA. With the growing recognition of the Classification Criteria for Psoriatic Arthritis, more homogenous and comparable prevalence estimates are expected to be reported.

Body mass index, abdominal fatness, weight gain and the risk of psoriasis: a systematic review and dose-response meta-analysis of prospective studies

Greater body mass index (BMI) has been associated with increased risk of psoriasis in case–control and cross-sectional studies, however, the evidence from prospective studies has been limited. We conducted a systematic review and dose–response meta-analysis of different adiposity measures and the risk of psoriasis to provide a more robust summary of the evidence based on data from prospective studies. PubMed and Embase databases were searched for relevant studies up to August 8th 2017. Summary relative risks (RRs) and 95% confidence intervals (CIs) were calculated using a random effects model. The summary relative risk (RR) for a 5 unit increment in BMI was 1.19 (95% CI 1.10–1.28, I² = 83%, n = 7). The association appeared to be stronger at higher compared to lower levels of BMI, p_nonlinearity < 0.0001, and the lowest risk was observed at a BMI around 20. The summary RR was 1.24 (95% CI 1.17–1.31, I² = 0%, p_{heterogeneity} = 0.72, n = 3) per 10 cm increase in waist circumference, 1.37 (95% CI 1.23–1.53, I² = 0%, p_{heterogeneity} = 0.93, n = 3) per 0.1 unit increase in waist-to-hip ratio, and 1.11 (95% CI 1.07–1.16, I² = 47%, p_{heterogeneity} = 0.15, n = 3) per 5 kg of weight gain. Adiposity as measured by BMI, waist circumference, waist-to-hip ratio, and weight gain is associated with increased risk of psoriasis.

The Association Between Obesity and Clinical Features of Psoriatic Arthritis: A Case-control Study

Objective.

To assess whether obesity is associated with distinct psoriatic arthritis (PsA) features and whether it interacts with PsA HLA susceptibility alleles.

Methods.

Patients with early PsA were compared with patients with psoriasis without arthritis (PsC). The primary predictor was the body mass index (BMI) at the first visit to the clinic. The clinical features across 3 BMI groups were compared by linear trend test and Cochrane-Armitage trend test. The interaction between BMI and HLA risk alleles for psoriatic disease (HLA-B*27, B*3901, B*3801, B*0801, B*4402, B*4403, and C*0602) were assessed using logistic regression analysis.

Results.

There were 314 patients with early PsA, and 498 patients with PsC were analyzed. Obesity was more frequent in patients with PsA compared with PsC (OR 1.77; p = 0.002). Higher BMI was associated with older age at onset of PsA (p < 0.0001) and psoriasis (p = 0.009). The frequency of HLA-B*27 was higher in patients with normal weight compared with those with higher BMI (p = 0.002). A significant interaction was found for the combined effect of HLA-B*27 and obesity in logistic regression analysis (p = 0.036). In patients who were HLA-B*27–negative, the association between obesity and PsA was statistically significant (OR 2.39; p < 0.001), but obesity was less frequent in patients with PsA who were HLA-B*27–positive.

Conclusion.

Obesity is linked with late-onset psoriasis and PsA, while normal weight is associated with the presence of the HLA-B*27 allele and an earlier onset of the disease. These results highlight the differential risk factors that may drive the inflammatory process in psoriatic disease.

The relationship between body mass index, waist circumference and psoriatic arthritis in the Turkish population

Introduction

Psoriasis is a chronic, immune-mediated inflammatory disease predominantly affecting the skin, with a complex aetiology. Recently it has been suggested that the chronic inflammation of psoriasis may cause metabolic and vascular disorders. The relationship between obesity and psoriatic arthritis (PsA) is not clear, and there are insufficient prospective studies addressing this subject.

Aim

To investigate the relationship between psoriatic arthritis, severity of psoriasis and obesity in the Turkish population.

Material and methods

Patient data from psoriasis outpatient clinics from February 2007 to July 2013 were reviewed retrospectively using the Psoriasis-Turkey (PSR-TR) registration system. Patients’ age, onset age, body mass index (BMI), waist circumference, psoriasis area and severity index (PASI), and arthritis information were reviewed. In the outpatient clinics, patients who had joint pain consulted rheumatology clinics. The CASPAR criteria were used for the diagnosis of arthritis.

Results

A total of 443 males and 495 females enrolled in this study. The mean age of females was 43.9 years (18–93 years) and the mean age of males was 44.6 years (18–89 years). A total of 231 (25%) patients had psoriatic arthritis. Investigation of the relationship between PASI, BMI, waist circumference (WC) and arthritis revealed a statistically significant relationship between each variable.

Conclusions

In this study we observed a relationship between PsA and high BMI, high WC and high PASI. Psoriatic arthritis is a chronic inflammatory disorder and a chronic inflammatory state induced by adiposity may lead to PsA.

Psoriasis: classical and emerging comorbidities

Psoriasis is a chronic inflammatory systemic disease. Evidence shows an association of psoriasis with arthritis, depression, inflammatory bowel disease and cardiovascular diseases. Recently, several other comorbid conditions have been proposed as related to the chronic inflammatory status of psoriasis. The understanding of these conditions and their treatments will certainly lead to better management of the disease. The present article aims to synthesize the knowledge in the literature about the classical and emerging comorbidities related to psoriasis.

Evaluation of body composition parameters in patients with psoriasis

BACKGROUND

Body composition parameters, such as weight, body mass index (BMI), and visceral fat rating, have been found to be associated with psoriasis. However, the associations of these parameters with psoriasis have not been demonstrated clearly.

OBJECTIVES

This study aimed to evaluate body composition parameters in patients with psoriasis.

METHODS

The relationships between the various body composition parameters and psoriasis were retrospectively examined in 242 patients with plaque psoriasis (119 women, 123 men) over a 2-year period during 2010-2012. In addition, the correlations between body composition parameters and Psoriasis Area and Severity Index (PASI) score were evaluated in treated and untreated patients with psoriasis. Patients were divided into two groups according to whether or not they had received systemic therapy within the previous three months. Body composition values were measured using the Tanita SC-330 Body Composition Analyzer(®).

RESULTS

Statistically significant differences were recorded in terms of weight (kg), body fat percentage, fat mass (kg), total body water (TBW) percentage, metabolic age, visceral fat rating, BMI, and degree of obesity among treated and untreated patients and control subjects. Differences in fat-free mass (FFM) (kg), muscle mass (kg), TBW (kg), and bone mass (kg) were found to be close to the limit for significance. The treated and untreated groups showed no significant differences in any of the parameters evaluated. The correlations between PASI score and the various parameters provided some evidence for such relationships.

CONCLUSIONS

The present study provides evidence of a relationship between some body composition parameters and the occurrence of psoriasis. We suggest that body composition parameters should be analyzed not only in obese psoriasis patients but in all psoriasis patients upon their first diagnosis. Systemic therapy does not appear to cause any changes in body composition parameters.

Combined effects of the BDNF rs6265 (Val66Met) polymorphism and environment risk factors on psoriasis vulgaris

Smoking, alcohol consumption and higher body mass index (BMI) are well established risk factors for psoriasis and also associated with the clinical traits of the disease. And the genetic influences on these three risk factors indeed exist. Previously studies have demonstrated these risk factors related genetic variants may also play a role in the development of risk factors-related diseases. Then we performed a hospital-based study in order to evaluate the combined effect of the risk factors and their related polymorphism rs6265 in brain-derived neurotrophic factor (BDNF) gene on psoriasis vulgaris (PV) risk and clinic traits. The case-control study involved 660 subjects including 345 cases and 315 controls in Chinese Han population. The variant of rs6265 was typed by SNaPshot Multiplex Kit (Applied Biosystems Co., USA). We confirmed that higher BMI (≥25), smoking and alcohol consumption were risk factors for PV, and the estimated ORs were 1.63(95 % confidence interval (CI); 1.12-2.37), 2.09(95 % CI; 1.44-3.03) and 1.65(95 % CI; 1.15-2.37) respectively. Genotype and allele distributions did not differ significantly between case and control. However, we found combined effect of rs6265 genotype (GG) and higher BMI (≥25) increased risk of PV (OR = 2.09; 95 % CI, 1.02-4.28; P < 0.05; adjusted OR = 3.19; 95 % CI, 1.37-7.45; P < 0.05) and clinically severity of PV (OR = 2.71; 95 % CI, 1.09-6.72; P < 0.05; adjusted OR = 1.25; 95 % CI, 1.10-1.40; P < 0.05). But none such significant combined effect was observed between others genotype (AA and AG) and other risk factors. In conclusions, the combined effect of BDNF rs6265 genotype (GG) and higher BMI may increases the risk and clinical severity of PV in Chinese Han population.

Combined effect between CHRNB3-CHRNA6 region gene variant (rs6474412) and smoking in psoriasis vulgaris severity

BACKGROUND

Many factors associated with causing psoriasis have been reported, such as the genetic and environmental factors. Smoking is one of the well-established environmental risk factors for psoriasis and also associated with the disease severity. In addition, several studies of psoriasis and psoriatic arthritis have documented gene-environment interactions involving smoking behavior. Although gene polymorphisms on nicotinic acetylcholine receptor subunits CHRNB3-CHRNA6 region gene have been found to correlate with smoking behavior and lung cancer susceptibility in Chinese Han population, the combined effect between the smoking-related genetic variants and smoking behavior on psoriasis vulgaris (PV) has been unreported.

OBJECTIVE

To evaluate the combined effect of the smoking-related (rs6474412-C/T) polymorphism on CHRNB3-CHRNA6 region gene and smoking behavior on PV risk and clinic traits in Chinese Han population.

METHODS

A hospital-based case-control study including 672 subjects (355 PV cases and 317 controls) was conducted. The variant of rs6474412 was typed by SNaPshot Multiplex Kit (Applied Biosystems Co., USA).

RESULTS

The higher body mass index (BMI≥25), smoking behavior and alcohol consumption were risk factors for PV, and the estimated ORs were 1.55 (95% CI, 1.09-2.29), 1.74 (95% CI, 1.22-2.49) and 1.81 (95% CI, 1.25-2.62) respectively. The smoking patients had more severe conditions than non-smokers (OR=1.71, 95% CI, 1.08-2.70, P=0.020). The alleles and genotypes of rs6474412 were not associated with risk of PV, but the combined effect of rs6474412 genotype (TT) and smoking behavior increased severity of PV (OR=5.95; 95% CI, 1.39-25.31; P<0.05; adjusted OR=2.20; 95% CI, 1.55-3.14; P<0.001).

CONCLUSIONS

Our results demonstrate that the combined effect of rs6474412-C/T polymorphism in smoking-related CHRNB3-CHRNA6 region gene and smoking behavior may not confer risk to PV, but may have impact on PV severity in Chinese Han population.

Obesity is associated with a lower probability of achieving sustained minimal disease activity state among patients with psoriatic arthritis

AIM

To assess whether overweight and obese patients with psoriatic arthritis (PsA) are less likely to achieve sustained minimal disease activity (MDA) state compared to patients with normal weight.

METHODS

A cohort of patients was assessed at the University of Toronto PsA clinic at 6-12-month intervals according to a standard protocol from 2003 to 2012. Patients were categorised into the following groups according to their body mass index (BMI): normal (<25), overweight (25-30), and obese (>30). Sustained MDA was defined as achieving low disease activity state in five or more of the following domains for at least 1 year: skin, enthesitis, tender and swollen joint counts, pain, patient global assessment and function. Proportional odds discrete time to event analysis was used to investigate the association between BMI category and the achievement of sustained MDA.

RESULTS

Of the 557 patients included in the study, 36.2% were classified as overweight and 35.4% were obese. Overall, 66.1% of the patients achieved sustained MDA during the follow-up period. A dose-response association was found between obesity and the probability of achieving sustained MDA in the multivariate regression analysis. Patients in the higher BMI categories were less likely to achieve sustained MDA compared those in the lowest BMI category (overweight: OR 0.66 p=0.003; obese: OR 0.53 p<0.0001) after adjusting for potential confounding variables.

CONCLUSIONS

Overweight and obese patients with PsA are less likely to achieve sustained MDA compared to those of normal weight.

The association between psoriasis and obesity: a systematic review and meta-analysis of observational studies

Objective:

Psoriasis is an inflammatory skin disease affecting 2–4% of the world population. The objective of this study was to perform a systematic review and meta-analysis synthesizing the epidemiological associations between psoriasis and obesity.

Data sources:

We searched for observational studies from MEDLINE, EMBASE and Cochrane Central Register from 1 January 1980 to 1 January 2012. We applied the Meta-Analysis of Observational Studies in Epidemiology guidelines in the conduct of this study.

Study selection:

We identified 16 observational studies with a total of 2.1 million study participants (201 831 psoriasis patients) fulfilling the inclusion criteria.

Results:

Using random-effects meta-analysis, the pooled odds ratio (OR) for obesity among patients with psoriasis was 1.66 (95% confidence interval (CI) 1.46–1.89) compared with those without psoriasis. From the studies that reported psoriasis severity, the pooled OR for obesity among patients with mild psoriasis was 1.46 (95% CI 1.17–1.82) and the pooled OR for patients with severe psoriasis was 2.23 (95% CI 1.63–3.05). One incidence study found that psoriasis patients have a hazard ratio of 1.18 (95% CI 1.14–1.23) for new-onset obesity.

Conclusions:

Overall, compared with the general population, psoriasis patients have higher prevalence and incidence of obesity. Patients with severe psoriasis have greater odds of obesity than those with mild psoriasis.

Reliability and validity of the Chinese version of the Psoriasis Disability Index (PDI) in Chinese patients with psoriasis

Background

The Psoriasis Disability Index (PDI) is a widely used instrument to measure the impact of psoriasis on patients. There has not been psychometric evaluation of the Chinese version of PDI. The aim of this study was to evaluate its reliability and validity among Chinese patients with psoriasis.

Methods

A multi-center, cross-sectional study was conducted at 9 hospitals including patients aged 18 years and over. Reliability was determined by internal consistency using Cronbach’s alpha. Validity was assessed through convergent validity and known groups validity. Dimensionality of the PDI was examined by exploratory factor analysis in working patients and nonworking patients respectively.

Results

In all, 831 patients were studied. Internal consistency of the PDI was satisfactory. Cronbach’s alpha coefficient was 0.91 for the total score and over 0.70 for each subscale of the PDI. Evidence of convergent validity of the PDI was proved by excellent and moderate to good correlations with the Dermatology Life Quality Index (DLQI) and four subscales of the Short Form-36 (SF-36) (role-physical, bodily pain, social functioning, and role-emotional): r = 0.51-0.78. Known groups validity was confirmed that the PDI score discriminated well among patients with different severity of psoriasis. The dimensionality of the PDI was determined by the presence of two-factor structure for working patients and three-factor structure for nonworking patients which accounted for 57.3% and 62.3% of the variance respectively.

Conclusion

The Chinese version of the PDI is a reliable and valid instrument to assess the impact of psoriasis on patients’ lives and could be used in future quality of life assessment of Chinese patients with psoriasis.

[Nail psoriasis in individuals with psoriasis vulgaris: a study of 661 patients]

BACKGROUND AND OBJECTIVES

The nails are affected in a substantial number of patients with psoriasis. Nevertheless, few epidemiological studies have reported the characteristics of patients with nail psoriasis. Here we describe the epidemiology of nail psoriasis and the main characteristics of affected patients.

PATIENTS AND METHODS

We undertook a prospective case-control study at Hospital Universitario Marqués de Valdecilla and Hospital Universitario Central de Asturias in Spain between January 2007 and December 2009.

RESULTS

Of a total of 661 patients included, 47.4% were diagnosed with nail psoriasis, which was 13.5% more prevalent in men. The group of patients with nail disease had more severe psoriasis (12.82 vs 8.22 points on the psoriasis area and severity index) and a longer disease duration (20.30 vs 13.94years), and included a larger percentage of patients with psoriatic arthritis (29.7% vs 11.5%), a positive family history of the disease (53.7% vs 42.8%), and a body mass index greater than 30 (31.6% vs 23.9%). A larger percentage of the patients with nail disease had early-onset psoriasis (74.1% vs 65.5%) and fewer were carriers of the human lymphocyte antigen Cw*0602 allele (33% vs 50.3%).

CONCLUSIONS

Nail disease is frequent in psoriasis and is associated with greater severity of psoriasis and a larger number of comorbidities.