The relation between synovitis of individual finger joints and grip force over the first 5 years in early rheumatoid arthritis - a cohort study.

OBJECTIVE: The objective of this study was to investigate the relation between swelling and tenderness of individual finger joints and grip force in patients with early rheumatoid arthritis (RA). METHODS: In an inception cohort of patients with early RA (symptom duration < 12 months), all patients were examined by the same rheumatologist, and grip force was measured using the Grippit instrument at inclusion, 1 and 5 years. The average grip force values of each hand were evaluated and expressed as % of expected values, based on age- and sex-specific reference values. Linear regression analyses were used to assess the cross-sectional relation between the involvement of individual finger joints and grip force. In generalized estimating equations, the impact of time-varying synovitis/tenderness on grip force over time was estimated. Analyses were adjusted for wrist involvement, erythrocyte sedimentation rate, and patient-reported pain. RESULTS: In 215 patients with early RA, grip force was 39% of expected at diagnosis, and increased to 56% after 5 years. Synovitis of the first metacarpophalangeal (MCP) joint (60% and 69% at baseline in the right and left hand) was associated with reduced grip force at inclusion (adjusted ß - 9.2 percentage unit of expected grip force; 95% CI - 13.6 to - 4.8 for both hands combined) and at all follow-up evaluations. Synovitis of MCP I and MCP IV (12% at baseline) was significantly associated with reduced grip force over time in both hands. Proximal interphalangeal (PIP) joint swelling, and tenderness of MCP or PIP joints, had less impact on grip force. CONCLUSION: MCP I synovitis is the major contributor to reduced grip force in patients with early RA. This underlines the importance of the involvement of the thumb for impaired hand function in RA. MCP IV synovitis, but not PIP involvement or finger joint tenderness, also has a substantial impact on grip force.

Predictors of unacceptable pain with and without low inflammation over 5 years in early rheumatoid arthritis-an inception cohort study.

OBJECTIVES: Pain is a major symptom in patients with rheumatoid arthritis (RA). In early RA, pain is usually due to synovitis, but can also persist despite effective anti-inflammatory treatment. The objective of this study was to investigate the pain course over time and predictors of unacceptable pain and unacceptable pain with low inflammation, in patients with early RA. METHODS: An inception cohort of 232 patients with early RA, recruited in 1995-2005, was followed in a structured programme for 5 years. Pain was assessed using a visual analogue scale (VAS; 0-100). Unacceptable pain was defined as VAS pain > 40 based on the patient acceptable symptom state (PASS) and low inflammation as CRP < 10 mg/l. Baseline predictors of unacceptable pain were evaluated using logistic regression analysis. RESULTS: Pain improved significantly during the first 6 months, but then remained basically unchanged. Thirty-four per cent of the patients had unacceptable pain 5 years after inclusion. Baseline predictors of unacceptable pain after 5 years were lower swollen joint counts [odds ratio (OR) 0.71 per standard deviation (95% confidence interval (CI) 0.51-0.99)] and higher VAS for pain and global assessment of disease activity. Unacceptable pain with low inflammation after 5 years was negatively associated with anti-CCP antibodies [OR 0.50 (95% CI 0.22-0.98)]. CONCLUSION: Over one third of the patients had unacceptable pain 5 years after inclusion. Lower swollen joint count was associated with unacceptable pain at 5 years. The results may be explained by the positive effects of treatment on pain related to inflammation. Non-inflammatory long-lasting pain appears to be a greater problem in anti-CCP-negative patients.

The Relation Between Disease Activity, Patient-Reported Outcomes, and Grip Force Over Time in Early Rheumatoid Arthritis.

OBJECTIVE: The objective of this study is to identify early predictors of future reduced grip force in patients with rheumatoid arthritis (RA) and to identify early predictors of grip force over time. METHODS: In a structured follow-up of an inception cohort of patients with early RA, average grip force values of the dominant hand were evaluated and compared with the expected based on age- and sex-specific reference values. Potential predictors of reduced grip force (less than 50% of expected) at 5 years were examined using logistic regression. Differences in percentage of expected grip force values over the study period and differences in change over time, by baseline disease parameters, were estimated using mixed linear-effects models. RESULTS: Among 200 patients with early RA, 44% had reduced grip force 5 years after diagnosis. Baseline characteristics that predicted reduced grip force at 5 years included high scores for the Health Assessment Questionnaire Disability Index (odds ratio 1.54 per SD; 95% confidence interval 1.13-2.11), high scores for pain and patient global assessment, and low grip force. C-reactive protein levels, the erythrocyte sedimentation rate, the 28-joint Disease Activity Score (DAS28), rheumatoid factor, anti-cyclic citrullinated peptide antibodies, joint counts, and synovitis of individual joints in the dominant upper extremity did not predict reduced grip force. Patients with baseline synovitis of the wrist or metacarpophalangeal joints or patients with a high DAS28 had lower estimated grip force at inclusion but also greater improvement of grip force over time. CONCLUSION: Patient-reported outcomes predicted reduced grip strength 5 years after diagnosis. This underlines the prognostic importance of disability in early RA. Joint counts and synovitis in individual joints may change rapidly in early RA and appear to be less predictive of long-term hand function.

The relation between upper extremity joint involvement and grip force in early rheumatoid arthritis: a retrospective study.

To investigate the relation between joint involvement in the upper extremities and grip force in patients with early rheumatoid arthritis (RA). An inception cohort of 225 patients with early RA was followed according to a structured protocol. The same rheumatologist assessed all patients for swollen joints and joint tenderness. Grip force was measured (Grippit; AB Detektor, Gothenburg, Sweden) at the same visit. Average grip force values for the dominant hand were expressed as % of expected, based on age- and sex-specific reference values from the literature. Associations between grip force and current synovitis or tenderness of individual joints, and other disease parameters measured at the same visit, were examined. Patients with current synovitis of the wrist joint or ≥ 1 metacarpophalangeal (MCP) joint of the dominant hand had a significantly lower grip force at inclusion, at 1 year and at 5 years. Proximal interphalangeal joint tenderness and MCP joint tenderness were consistently associated with reduced grip force. In multivariate analysis, extensive MCP joint synovitis was associated with lower grip force at inclusion (ß - 2.8% per joint; 95% CI - 5.3 to - 0.4), and also at the 1-year follow-up. Patient reported pain scores and erythrocyte sedimentation rates had independent negative associations with grip force at all time points. In patients with early RA, extensive synovitis of the MCP joints was associated with reduced grip force, independently of other upper extremity joint involvement. Pain and inflammation have effects on hand function beyond those mediated by local synovitis.

Course of Grip Force Impairment in Patients With Early Rheumatoid Arthritis Over the First Five Years After Diagnosis.

OBJECTIVE: Objective measures of function are important in rheumatoid arthritis (RA). The objective of this study was to investigate grip strength in patients with early RA. METHODS: An inception cohort of 225 patients with early RA was followed in accordance with a structured protocol. Average and peak grip force values of the dominant hand (measured using a Grippit device [AB Detektor]) were evaluated and compared to expected age- and sex-specific reference values from the literature. Separate analyses were performed for those with limited self-reported disability (Health Assessment Questionnaire disability index [HAQ DI] score ≤0.5) and clinical remission (Disease Activity Score in 28 joints <2.6). RESULTS: Baseline average grip force among RA patients was significantly lower than the corresponding expected value (mean 105N versus 266N; P < 0.001). Observed average and peak grip force values were significantly reduced compared to those expected in women as well as in men over time and at all time points. The average grip force improved significantly from inclusion to the 12-month visit (age-corrected mean change 34N [95% confidence interval 26-43]). At 5 years, the average grip force was still lower than that expected overall (mean 139N versus 244N; P < 0.001), and also among those with HAQ DI scores ≤0.5 and those in clinical remission. CONCLUSION: Grip strength improved in early RA patients, particularly during the first year. However, it was still significantly impaired 5 years after diagnosis, even among those with limited self-reported disability and those in clinical remission. This suggests that further efforts to improve hand function are important in early RA.