Depression and Anxiety Reduce the Probability of Achieving a State of Sustained Minimal Disease Activity in Patients With Psoriatic Arthritis.

OBJECTIVE: We aimed to determine whether the presence of depression or anxiety is associated with the achievement of sustained minimal disease activity (MDA) in patients with psoriatic arthritis (PsA). METHODS: Adult patients satisfying classification criteria for PsA prospectively followed from 2008 to 2017 were included. A standard protocol including physician assessment and patient-reported outcomes determined whether patients achieved sustained MDA, which was defined as meeting MDA criteria for ≥2 consecutive visits. The presence of depression/anxiety was determined using 3 definitions: 1) a score of ≤38 on the mental component summary of the Medical Outcomes Study Short Form 36 (SF-36) health survey, 2) a score of ≤56 on the mental health domain of the SF-36 health survey, and 3) a rheumatologist's report of a diagnosis or treatment for depression/anxiety. A discrete time-to-event analysis was conducted based on a proportional odds model to identify factors associated with achieving sustained MDA. RESULTS: A total of 743 patients were included in the study. The number of patients identified as having depression/anxiety at baseline included 331 patients (44.54%) according to definition 1, 364 patients (48.99%) according to definition 2, and 211 patients (28.4%) according to definition 3. A total of 337 patients (45.36%) did not achieve sustained MDA. The presence of depression/anxiety was associated with reduced probability of achieving sustained MDA, with odds ratio (OR) 0.30 (P < 0.0001), OR 0.34 (P < 0.0001), and OR 0.47 (P < 0.0001) for definitions 1, 2, and 3, respectively. Other variables associated with a reduced probability of achieving sustained MDA included the Charlson comorbidity index and fibromyalgia. CONCLUSION: Symptoms of anxiety/depression reduce the probability of achieving sustained MDA in PsA. Comprehensive management of PsA should include measures for addressing these comorbidities.

Oligoarticular vs Polyarticular Psoriatic Arthritis: A Longitudinal Study Showing Similar Characteristics.

OBJECTIVE: The objectives of this study were to determine whether patients with oligoarticular presentation differ from those with polyarticular presentation and to identify potential predictors for evolution of oligoarthritis to polyarthritis in patients with psoriatic arthritis (PsA). METHODS: Patients who entered the University of Toronto PsA clinic between 1978 and 2018 within 12 months of diagnosis were identified. Only patients with ≥ 2 clinic visits were included. Patients were followed at 6- to 12-month intervals according to standard protocol, which included demographics, clinical history, detailed clinical examination, laboratory information, and patient questionnaires. Radiographs were done at 2-year intervals. Oligoarthritiswas defined by the presence of ≤ 4 inflamed joints and progressionas an increase to ≥ 5 joints. Statistical analyses included logistic regression models as well as Weibull regression models, adjusted for age, disease duration, and sex. RESULTS: Of 407 patients, 192 (47%) presented with oligoarthritis. Whereas demographic features were similar to those with polyarthritis, more patients with polyarthritis presented with dactylitis and enthesitis. Similar joint distribution was observed, with small joints of the hands and feet being most commonly affected. Patients with polyarthritis had higher Health Assessment Questionnaire and lower 36-item Short Form Health Survey (SF-36) scores. Of the 192 oligoarticular patients, 117 (61%) remained oligoarticular and 75 (39%) progressed to polyarthritis. A lower SF-36 mental component summary (MCS) score was the predictor for progressing to polyarthritis. CONCLUSION: Oligoarticular PsA occurs in 47% of patients with PsA and is similar to polyarticular disease, with most patients having small joint involvement. The only predictor for progression to polyarthritis was lower SF-36 MCS.

Axial Disease in Psoriatic arthritis: The presence and progression of unilateral grade 2 sacroiliitis in a psoriatic arthritis cohort.

BACKGROUND/PURPOSE: A universally accepted definition of axial psoriatic arthritis (axPsA) is lacking. We aimed to 1) assess the presence of axial involvement as defined by "at least unilateral grade 2 sacroiliitis (Uni2SI)" and 2) assess the radiographic progression of Uni2SI and identify risk factors for progression. METHODS: PsA patients participating in a prospective observational cohort were classified according to their highest sacroiliitis grade. The baseline features of patients with Uni2SI were compared to patients meeting the radiographic criteria of the modified New York Ankylosing Spondylitis (mNY AS) criteria. Risk factors were examined for progression from Uni2SI in a sub-group of patients with >1 follow-up radiographs. Logistic regression and a survival analysis were carried out and identified risk factors associated with radiographic mNY AS compared to Uni2SI. RESULTS: Axial disease defined as ≥Uni2SI was detected in 612/1354 patients (45%). mNY AS sacroiliitis was observed in 477 patients (35%). Radiographic progression of Uni2SI was assessed in 154 patients, 80 (52%) progressed to mNY AS criteria within 5.5 years. At baseline, progressors were diagnosed at a younger age (35.6 vs. 38.9, p = 0.05), had less degenerative disc disease (OR = 0.47, p = 0.02), worse peripheral radiographic damage (OR=1.02, p = 0.03) and worse psoriasis (OR = 1.09, p = 0.01) compared to non-progressors. Patients with an elevated erythrocyte sedimentation rate were more likely to progress (HR = 1.83, p = 0.02), while patients with longer disease duration were less likely to progress (HR = 0.95, p = 0.02). CONCLUSION: The radiographic mNY AS criteria appear to be suitable for defining axial PsA according to radiographs. MRI definitions are needed as well for the most appropriate definition of axial PsA.

Malignancy in psoriatic disease: Results from prospective longitudinal cohorts.

OBJECTIVES: To estimate the prevalence and incidence of malignancy and its types in psoriatic arthritis (PsA) and psoriasis without arthritis (PsC) patients, in comparison to the general population, and to identify the predictive factors for developing cancer in psoriatic disease (PsD). METHODS: PsA patients followed prospectively since 1978 and PsC patients followed since 2006 at 6-to-12 month intervals according to a standard protocol were included. Malignancies were recorded prospectively and linkages with Cancer Care Ontario and the Death Registry were carried out to confirm the presence and type of malignancy up to December 2016. Standardized incidence ratios (SIR) were calculated for overall cancers and by age and sex. Cox regression analysis was conducted to identify risk factors associated with the development of malignancy after the diagnosis of PsD. RESULTS: 2051 patients (PsD) were included of whom 228 (11%) developed cancer. 168 patients developed cancer after first clinic visit and are included in this report. Overall SIR for malignancy was 0.83 (0.68, 1.00), SIR for females was 1.06 (0.80, 1.37), and for males was 0.67 (0.50, 0.88). The most common malignancies were skin, breast, and hematological. Skin cancer was the only specific cancer that had a higher incidence than the general population with SIR = 3.37 (1.84, 5.66). There was insufficient evidence to suggest an increased risk of malignancy associated with biologics use. CONCLUSIONS: In this long-term prospective follow-up of patients with PsA and PsC the overall malignancy risk was not found to be higher than the general population, while skin cancer increased.

Mortality in psoriatic arthritis: Risk, causes of death, predictors for death.

BACKGROUND/OBJECTIVES: Mortality studies in psoriatic arthritis (PsA) have provided inconsistent results. This study aimed to: 1) Estimate trends in mortality rates among PsA patients over calendar time; 2) Evaluate cause-specific mortality rates in patients with PsA compared to the general population; 3) Identify predictors for mortality in PsA. METHODS: The study was carried out at the University of Toronto Psoriatic Arthritis Clinic where patients are followed prospectively according to a standard protocol at 6- to 12- month intervals. Standardized mortality ratios (SMRs) were calculated overall, by age, and by sex with reference to the Ontario population. Causes of death were recorded by ICD9 and ICD10 codes and cause-specific SMRs were computed. Cox regression models were used to identify predictors for mortality among PsA patients. RESULTS: Among 1490 patients followed over 15062.8 patient-years, 225 (15%) confirmed deaths were recorded (111 females, 114 males). The overall SMR was 0.92 (95% CI: 0.81-1.05), the sex-specific SMRs were 1.08 (95% CI: 0.89-1.30) for females and 0.81 (95% CI: 0.66-0.97) for males. The age-specific SMRs were 3.36 (95% CI: 1.61-6.18), 0.97 (95% CI: 0.68-1.34), 0.88 (95% CI: 0.73-1.06) and 0.86 (95% CI: 0.66-1.11) for 20-39, 40-59, 60-79 and above 80 years of age, respectively. Major causes of death included malignant neoplasms (n=61; SMR=0.97, 95% CI: 0.72-1.28), acute myocardial infarction (n=32; SMR=1.11, 95% CI: 0.74-1.58), and pneumonia (n=14; SMR=2.46, 95% CI: 1.27-4.31). Factors found to be associated with increased mortality include elevated acute phase reactants, presence of comorbidities such as heart disease and cancer, and lower education level. CONCLUSION: Young patients with PsA are at increased mortality risk. Better control of comorbidities may reduce this risk.

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.

The relationship between patient acceptable symptom state and disease activity in patients with psoriatic arthritis.

OBJECTIVES: The Psoriatic Arthritis Disease Activity Score (PASDAS) and Disease Activity Index for Psoriatic Arthritis (DAPSA) are composite PsA disease activity measures. We sought to identify the PASDAS and DAPSA cut-off points consistent with patient acceptable symptom state (PASS), the threshold of symptoms beyond which patients consider themselves well, and examine PASS across published PASDAS and DAPSA thresholds for low, moderate and high disease activity. METHODS: We used a standard protocol including physician assessment and patient-reported outcomes to prospectively record measures required to calculate PASDAS and DAPSA. We identified PASS thresholds for the PASDAS and DAPSA using receiver operating characteristics curve analyses. We assessed the frequency of reporting acceptable symptom state across disease activity thresholds for PASDAS and DAPSA scores. RESULTS: A total of 229 patients (58.5% male, mean age 55.5 years, mean disease duration 17.1 years) were recruited. The PASS threshold for the PASDAS was 3.79 [area under the curve (AUC) 0.86, sensitivity 0.75, specificity 0.82] and for the DAPSA was 11.10 (AUC 0.91, sensitivity 0.89, specificity 0.82). With the PASDAS, 90% of patients defined as having low disease activity considered their symptom state acceptable, compared with 55% and 17% among those with moderate and high disease activity, respectively. With the DAPSA, 98% of patients in disease remission considered their symptom state acceptable compared with 85, 22 and 18% among those with low, moderate and high disease activity, respectively. CONCLUSION: We have defined PASS thresholds for PASDAS and DAPSA. The PASDAS target for low disease activity and DAPSA targets of low disease activity or remission align well with PASS.

A novel role for the psoriatic arthritis impact of disease (PsAID) questionnaire.

BACKGROUND: The Minimal Disease Activity (MDA) uses the Health Assessment Questionnaire (HAQ) as one criterion. HAQ does not correlate well with disease activity with increased PsA disease duration, and its use in the MDA has been questioned. The Psoriatic Arthritis Impact of Disease (PsAID) was specifically developed for PsA Patients. We aimed to validate the PsAID within our patient cohort and determine if the PsAID can replace the HAQ in the MDA. METHODS: Patients were recruited from the PsA clinic and assessed according to a standard protocol including demographics, clinical features and laboratory tests. Descriptive statistics were calculated. PsAID cut-offs for use in the MDA were generated based on the Clinical Disease Activity for Psoriatic Arthritis (cDAPSA). RESULTS: 115 patients completed the PsAID. There were 70 males, 45 females, with a mean PsA duration of 18.7 (±11.6) years. Mean scores of PsAID-9 and PsAID-12 were 3.4 (±2.4) and 3.2 (±2.3), respectively. The PsAID correlated moderately well with 9 of the PROMs administered in the clinic (ρ = 0.51-0.78). Four PsAID cutoffs based on cDAPSA were generated for use in the MDA: remission (REM) PsAID-9, REM PsAID-12, low disease activity (LDA) PsAID-9, and LDA PsAID-12. All four versions of the PsAID MDAs had sensitivity greater than 85% with the HAQ-MDA, and three versions of the PsAID-MDA had specificity greater than 85% with the HAQ-MDA. CONCLUSIONS: The high sensitivity and specificity of the PsAID-MDA with the HAQ-MDA suggest that the PsAID is an effective replacement for the HAQ in the MDA.

Back pain in psoriatic arthritis: defining prevalence, characteristics and performance of inflammatory back pain criteria in psoriatic arthritis.

OBJECTIVE: We aimed to determine the agreement between rheumatologist-judged inflammatory back pain (IBP) and criteria defining IBP in patients with psoriatic arthritis (PsA) and predictive value of IBP in identifying axial involvement in PsA. METHODS: Using prospectively collected data, we investigated the agreement between rheumatologist judgement of IBP and IBP criteria (Calin, Rudwaleit and Assessment of Spondyloarthritis International Society) using the kappa coefficient. We also determined the sensitivity, specificity and likelihood ratios of the presence of back pain, rheumatologist-judged IBP and the three IBP criteria for detecting axial PsA (AxPsA). Finally, we compared the clinical and genetic markers in patients with PsA with axial radiological changes with and without back pain. RESULTS: 171 patients (52% male, mean age 46.6 years) were identified. Ninety-six (56.13%) patients reported chronic back pain. Sixty-five (38.01%) had IBP. 54 (32%) patients had evidence of radiological change in the spine. The agreement between rheumatologist judgement of IBP and IBP criteria was highest for the Calin criteria (0.70). Positive likelihood ratio for the presence of radiological axial involvement was highest for Rudwaleit criteria (2.17). No differences between patients with AxPsA with or without back pain were found, except for higher Bath Ankylosing Spondylitis Disease Activity Index and lower prevalence of human leucocyte antigen-B*38 in those with back pain. CONCLUSION: Rheumatologist-judged IBP or the criteria for IBP developed for ankylosing spondylitis may not perform well when ascertaining axial involvement in PsA.