The incidence of disability pensions and mortality among semi-skilled construction workers in Copenhagen. A retrospective cohort study with two control groups

The aim of the present study was to discover whether the incidence of disability pensions and mortality was higher amongst semi-skilled construction workers (SCW) in Copenhagen than in two control groups from the same geographic area. The population investigated consisted of a fixed cohort of 3537 SCW from Copenhagen as per 1/5/1975. The two control groups comprised 3818 Copenhagen members of the Warehouse Workers' union and a group of Copenhagen members of the Semi-skilled Worker's Union age-matched to the SCW cohort, both as per 1/5/75. Up to 31/12/79, a total of 102 SCW were granted disability pensions, compared with 89 and 77 in the two control groups respectively, i.e. a significantly higher frequency of award of disability pension among SCW than among warehouse workers (p less than 0.05). This was due especially to a higher frequency of disability pensions granted because of musculoskeletal diseases and cancer in SCW. The number of deaths was recorded from 1/5/75 to 30/11/78. No differences in overall mortality were found among the three groups, although slightly fewer deaths from lung cancer and ischaemic heart diseases and more suicides were observed among the construction workers. Selection bias and the effect of the working environment are discussed against the background of a concurrent investigation of the state of health and working conditions of SCW.