Prevalence of rheumatic occupational diseases - PROUD study

Work related musculoskeletal diseases (WRMSDs) have a huge social and economic impact being a public health problem.

To determine the prevalence of WRMSDs in Portuguese active workers.

A questionnaire was sent by regular mail to the occupational physician of 822 large dimension companies in Portugal (over 250 employees). This questionnaire was addressed to the physician and contemplated data on file from the occupational medical doctor of clinically relevant WRMSDs (rather than addressing workers complaints). A reply form and a telephone reminder were used to assure a higher number of respondents.

Of the selected 822 companies, 515 responded (response rate of 62.3%) involving a total population of 410,496 workers. The prevalence of clinically relevant WRMSD was of 5.9% (24,269 cases). The more prevalent WRMSD were back pain with a prevalence of low back pain of 2.27% (n=9310 , 38.4% of total WRMSD). Dorsal pain 0.82% (n= 3379, 13.9% of total WRMSDs) and cervical pain 1.13% (n=4651, 19.2% of total WRMSD). Back pain accounts for 4.22% (n= 17340) and a total of 74.9% of all WRMSDs. Regarding the upper limb we found a prevalence of 1.61% (n= 6493). From this total, shoulder tendonitis was 0.59%(n= 2398, 9.9% of total WRMSDs), carpal tunnel syndrome 0.29% (n=1170, 4.8% of total WRMSDs), elbow tendonitis 0.29% (n=1202, 5% of total WRMSDs) and hand tendonitis 0.44% (n=1823, 7.5% of total WRMSDS). A lower prevalence was observed in the lower limbs with lower limb tendonitis of 0.08% (n=336, 0.01% of total WRMSDs).

Our work was representative of 11% of the working Portuguese population. We have found a prevalence of clinically relevant WRMSD of 5,9%. If we extrapolate for the total of the working population we would have 220 467 workers with WRMSDs. Our data are in conflict with national social security services regarding these diseases with much lower reported diseases that proves the inefficacy of the national reporting system. There are clear differences in our data when compared with the literature. We found a higher number of back pain, and in proportion of cervical pain, and lower numbers of upper and lower limb WRMSDs. In the upper limb we found a higher level of hand tendonitis and a decrease of elbow tendonitis and carpal tunnel syndrome. This work was a first effort to characterize WRMSDs in Portugal. Due to the study design we believe that further studies aimed for higher risk populations should be performed.