Table 3

Adjusted ORs (aORs) of having first-degree relatives affected by idiopathic inflammatory myopathies (IIMs) in patients with IIM compared with individual without IIM*

Patients with IIM, n/N (%)Individuals without IIM, n/N (%)aOR† (95% CI)aOR‡ (95% CI)
≥1 relative13/1620 (0.80)16/7797 (0.21)4.32 (2.00 to 9.34)
Any first-degree relatives13/7615 (0.17)16/37309 (0.04)2.61 (1.80 to 3.78)2.61 (1.80 to 3.79)
Parents2/2306 (0.09)5/11414 (0.04)
Full siblings9/2464 (0.37)10/11685 (0.09)2.54 (1.62 to 3.99)2.53 (1.62 to 3.96)
Offspring2/2845 (0.07)1/14210 (0.01)
  • *≥1 relative: comparison between patients with IIM and individuals without IIM; any first-degree relatives, parents, full siblings and offspring: comparison between relative pairs of patients with IIM and relative pairs of individuals without IIM.

  • †Controlled for sex, birth year and residential area of index persons.

  • ‡Controlled for sex, birth year and residential area of index persons, sex and birth year of first-degree relatives.