Methods

Patients

Patient members of the French SSc patient association (ASF) were asked to participate in a study during four consecutive annual meetings in 2004, 2005, 2006 and 2007. The proportions of patients who agreed of those who were asked to participate were 50 (44 women)/80 (62.5%) in 2004, 71 (59 women)/98 (72.4%) in 2005, 70 (55 women)/95 (73.7%) in 2006 and 70 (55 women)/101 (69.3%) in 2007. Overall, since some patients were evaluated several times, 177 different patients from the ASF were evaluated; only the first assessment of each patient was considered. In addition, 36 patients (21 women) were evaluated during hospitalisation in the Internal Medicine Department of Cochin Hospital.

To be eligible for the study, patients had to fulfil the American College of Rheumatology4 and/or the Leroy and Medsger5 criteria for SSc. Patients with localised scleroderma were excluded from the study. All patients were assessed during at least one of the four annual ASF meetings in spring (temperature 18–22°C) or, for 36 patients, during hospitalisation.

Demographic and clinical parameters

Parameters recorded were age; sex; ethnicity; occupation; sick leave; year of onset of Raynaud’s syndrome; age at diagnosis; year of onset of the first non-Raynaud’s phenomenon; disease duration; disease form (limited SSc, limited cutaneous SSc or diffuse SSc); weight and size; inter-incisor distance (mm); dyspnoea (New York Heart Association 4-point scale); pitting scars; DU; calcinosis; oesophagus, joint and/or muscle involvement; heart involvement; interstitial lung disease; pulmonary arterial hypertension; and renal crisis. Evidence of oesophagus, joint and/or muscle involvement; heart involvement; interstitial lung disease; pulmonary arterial hypertension; and scleroderma renal crisis was based on patient reports for patients evaluated at the association meetings and on clinical charts for patients evaluated in hospital. No distinction was made between DUs of vascular mechanisms, DUs complicating calcinosis and DUs secondary to trauma.

Physical ability was assessed by the Karnofsky performance status (KPS) scale (11 items), ranging from normal health (100%) to death (0%).6

In 2006 and 2007, patients were also asked by interview whether their health status was perfectly acceptable, acceptable, poorly acceptable or unacceptable, and aesthetic burden was assessed by asking the patient: “What is the global aesthetic repercussion of your SSc?” which was measured on an 11-point semi-quantitative scale (0–10).

Quality of life assessment

The French version of the SF-367 covers eight areas. For each area the score ranges from 0 (poorer health status) to 100 (better health status). Scores were also summarised in two global scores: the physical component score (PCS) and the mental component score (MCS).

Disability assessment

Global disability was assessed by the health assessment questionnaire (HAQ), the scale ranging from 0 (no disability) to 3 (maximal disability).7 8 Hand disability was evaluated with the Cochin hand function scale (CHFS),9 an 18-item questionnaire ranging from 0 (no disability) to 90 (maximal disability) validated for SSc.10 Mouth disability was evaluated by the Mouth Handicap in Systemic Sclerosis (MHISS) scale (range 0 (no disability) to 48 (maximum disability)).11

Global hand and wrist mobility assessment

Global hand and wrist mobility were evaluated by use of the hand functional index (HFI) and Kapandji index.12 13 The HFI score ranges from 4 (best mobility) to 42 (worst mobility) and the Kapandji score ranges from 0 (worst mobility) to 100 (best mobility).

Patients’ perceived disability

Patients’ perceived handicap was assessed using the McMaster-Toronto Arthritis Patient Preference Disability Questionnaire (MACTAR).14 Patients were asked to select the three situations among daily living activities that caused them maximal trouble. The global score ranges from 0 (no handicap) to 30 (maximal handicap). This questionnaire has been validated for SSc.6

Anxiety and depression assessments

Anxiety and depression were assessed by use of the Hospital Anxiety and Depression scale (HADa and HADd).15

Statistical analysis

Data analysis was performed using Systat 9 (SPSS Inc, Chicago, USA). Quantitative variables were described with means (SD) and ranges. Qualitative variables were described with proportions and percentages. For univariate analysis, quantitative variables were compared using of Student t test and categorical variables by the χ² test. A multivariate analysis was performed to determine factors associated with DUs. A backward stepwise regression analysis with values of 0.15 to enter and 0.10 to stay in the model was used. Variables entered in multivariate analysis were those with p values <0.5 in univariate analysis.

Results

Demographic and clinical data

The demographic and clinical characteristics of the 213 patients (175 women) studied are shown in table 1. Sixty-seven patients (31.4%) had at least one DU at the time of evaluation. The disease duration was longer in patients with DUs than in those without DUs (mean (SD) 12.6 (11.4) vs 9.5 (6.8) years, p = 0.043). The clinical presentation of SSc between patients with DUs and those without DUs did not differ significantly, with the exception of pitting scars (p<0.001) and calcinosis (p<0.0001) which were more frequent in patients with DUs.

Outcome measure scores

Patients with DUs had significantly greater global disability (mean (SD) HAQ score 1.218 (0.723) vs 0.930 (0.717), p = 0.008) and hand disability (CHFS 27.38 (20.68) vs 16.73 (18.19), p = 0.0001) than those without DUs upon univariate analysis (table 2). Patients with DUs showed a significant decrease in the MCS (39.58 (9.54) vs 43.38 (12.53), p = 0.026) of the SF-36 but no difference was noted in the PCS compared with those without DUs. Patients with DUs did not experience more anxiety and/or depression on the HAD scale. On multivariate analysis, factors associated with DUs were calcinosis (OR 2.33, 95% CI 1.04 to 5.19), CHFS score (OR 1.02, 95% CI 1.00 to 1.04) and aesthetic prejudice (OR 1.36, 95% CI 1.12 to 1.64).

Discussion

We provide evidence that patients with SSc with DUs have reduced wrist and hand mobility, increased global and hand disabilities and decreased mental aspect of HRQoL compared with those with no DU. Our results suggest that, in SSc, special efforts should be made to prevent or rapidly cure DUs and improve HRQoL.

These observed differences do not seem to be related to longer disease duration in patients with DUs, since the disease duration factor was not retained on multivariate analysis and individual correlations with disability and HRQoL were very low (Spearman correlation coefficients between 0.06 and 0.22).

Surprisingly, the presence of DUs did not alter the PCS of the SF-36, whereas the severity of Raynaud’s disease was found to predict a reduction in PCS in a cohort of patients with SSc or Raynaud’s disease plus antinuclear antibodies in a recent study.16 However, the presence of a DU is associated with a decreased MCS score of the SF-36. Because DUs are also associated with increased aesthetic burden, they may have implications on the MCS.

We did not find differences in MACTAR scores between patients with and without DUs. This finding may not be surprising, since we recently reported that the three main activities listed by patients with SSc as priority handicaps were walking, housekeeping and sport training.6 Indeed, although housekeeping comprises activities that involve the hands, as does sport training, the major limitations in complying with these activities are probably due to other restrictions.

The major limitation of our study is that no distinction was made between DUs of vascular mechanisms, DUs complicating calcinosis and DUs secondary to trauma. Since we did not distinguish between the different types of DUs, we cannot determine whether the decrease in hand mobility is a cause or a consequence of the DUs. In addition, our sample consisted largely of patients from the French national association of SSc with only a small number of patients hospitalised in a tertiary care hospital for treatment or follow-up. Thus, outcome measure scores for patients from our study are worse than in those assessed in a tertiary care setting.8 10 This sample might therefore not be representative of the entire SSc population in France, and the generalisability of our results cannot be ascertained. Further evaluation of this topic in other cohorts of patients with SSC is therefore necessary to confirm these findings. Finally, the use of multiple assessment tools may weaken the statistical analysis owing to multiple comparisons.

In conclusion, in patients with SSc, DUs have a negative impact on hand and global disabilities and on the mental component of HRQoL. More accurate prevention, treatment and rehabilitation programmes are needed for these patients to improve their HRQoL.