Table 1

Characteristics of cases with invasive pneumococcal disease (IPD) and matched controls from the general population of Sweden

All IPD (n=4438)Controls
(n=21 080)
IPD with pneumonia
(n=14 979)
Age, years (SD)51.5 (11.5)50.9 (11.2)51.2 (11.5)50.7 (11.3)
Completed university31.9%37.2%31.0%37.3%
Chronic obstructive pulmonary disease4.8%0.5%5.5%0.4%
Bronchial asthma6.8%2.0%7.5%2.0%
Diabetes mellitus9.8%1.5%10.0%1.5%
Ethanol abuse3.7%0.9%3.8%1.0%
Pneumococcal vaccination0.2%<0.1%0.1%<0.1%
 Welders and flame-cutters1.1%0.4%1.4%0.5%
 Foundry workers0.1%<0.1%<0.1%<0.1%
 Steel mill workers0.4%0.4%0.5%0.3%
 All metalworkers*2.1%1.0%2.4%1.1%
Occupational exposures based on job–exposure matrix
 All inorganic dust23.1%19.7%23.4%19.8%
 Silica dust4.7%3.2%4.6%3.2%
 Vapours and gases21.7%20.1%22.0%20.1%
 Organic dust8.2%8.3%7.8%8.4%
 Any exposure†39.8%36.0%40.4%36.2%
  • *A merger of welders (and flame-cutters), foundry workers, steel mill workers and blacksmiths.

  • †All five job–exposure matrix categories combined.