Table 1

Characteristics of patients included in the analysis

19971998199920002001200220032004200520062007
Number of cases35193727373536653556360038574020254931723323
Also seen in previous year (%)6569676566616364525264
Female79%78%78%79%79%79%79%79%76%76%76%
Mean±SD age (years)59.6±12.960.1±12.960.1±12.960.3±12.761.1±12.661.2±12.461.6±12.461.9±12.460.6±12.961.7±12.962.3±12.9
Mean±SD disease duration (years)9.0±8.89.4±8.69.5±9.09.4±8.810.2±9.210.6±9.110.7±9.210.8±9.310.3±9.710.9±9.811.4±10.1
 Disease duration ≤2 years (%)18.915.316.917.613.211.311.713.418.715.414.3
 Disease duration >2–10 years (%)48.850.848.748.348.648.447.645.640.840.840.1
 Disease duration >10 years (%)32.333.934.434.138.240.340.741.040.543.845.6