TABLE 1.

The Chicago Infant Mortality Study, 1993-1996: Unadjusted and Adjusted Univariate ORs for Variables in the Sleep Environment*

VariableSIDS CasesControlsUnadjusted OR (95% CI)Adjusted OR (95% CI)
N%N%
Surface
 Adult bed mattress148(56.9)151(58.1)ReferenceReference
 Crib49(18.9)63(24.2)0.8 (0.5–1.2)1.2 (0.7–2.2)
 Sofa/chair26(10.0)14(5.4)2.0 (0.96–4.1)1.6 (0.7–3.7)
 Other37(14.2)32(12.3)1.1 (0.7–1.9)1.3 (0.7–2.5)
Location
 Parent’s bedroom167(64.2)153(58.8)ReferenceReference
 Infant’s bedroom20(7.7)33(12.7)0.6 (0.3–1.1)0.8 (0.4–1.7)
 Other room in infant’s home47(18.1)46(17.7)0.9 (0.6–1.5)0.8 (0.5–1.5)
 Other26(10.0)28(10.8)0.8 (0.4–1.6)0.9 (0.4–1.9)
Prone sleep position
 No111(42.7)169(65.0)ReferenceReference
 Yes149(57.3)91(35.0)2.4 (1.7–3.4)2.3 (1.5–3.5)
Soft sleep surface
 No133(51.2)210(80.8)ReferenceReference
 Yes127(48.8)50(19.2)5.1 (3.1–8.3)5.1 (2.9–9.2)
Pillow use
 No192(73.8)224(86.1)ReferenceReference
 Yes68(26.2)36(13.9)2.5 (1.5–4.2)3.1 (1.6–5.8)
Head and/or face covered
 No224(86.1)245(94.2)ReferenceReference
 Yes36(13.9)15(5.8)2.5 (1.3–4.6)2.5 (1.2–5.2)
Wrapped/swaddled
 No231(88.8)234(90.0)ReferenceReference
 Yes29(11.2)26(10.0)1.1 (0.6–2.0)1.0 (0.5–1.9)
Sweating in last 2 days
 No247(95.0)243(93.5)ReferenceReference
 Yes13(5.0)17(6.5)0.8 (0.4–1.6)0.7 (0.3–1.7)
Runny nose/upper respiratory infection in last 2 d
 No143(55.0)197(75.8)ReferenceReference
 Yes117(45.0)63(24.2)2.5 (1.7–3.8)2.2 (1.3–3.5)
Pacifier use
 No221(85.0)177(68.1)ReferenceReference
 Yes39(15.0)83(31.9)0.3 (0.2–0.5)0.3 (0.2–0.5)
Breastfeeding (ever)
 No205(78.8)130(50.0)ReferenceReference
 Yes55(21.2)130(50.0)0.2 (0.1–0.3)0.4 (0.2–0.7)
Breastfeeding (current)
 No243(93.5)199(76.5)ReferenceReference
 Yes17(6.5)61(23.5)0.2 (0.1–0.4)0.3 (0.2–0.7)
Shared bed (with anyone)
 No129(49.6)181(69.6)ReferenceReference
 Yes131(50.4)79(30.4)2.7 (1.8–4.2)2.0 (1.2–3.3)
Shared bed (with mother alone or with mother and father)
 No129(49.6)181(69.6)ReferenceReference
 Yes, mother or mother and father70(26.9)59(22.7)1.9 (1.2–3.1)1.3 (0.7–2.3)
 Yes, with others61(23.5)20(7.7)5.4 (2.8–10.2)4.1 (2.0–8.4)
Shared room (with anyone)
 No75(28.8)108(41.5)ReferenceReference
 Yes185(71.2)152(58.5)1.8 (1.2–2.6)1.4 (0.9–2.3)
Shared room (with mother alone or with mother + father)
 No75(28.8)108(41.5)ReferenceReference
 Yes, mother or mother and father94(36.2)89(34.2)1.6 (1.1–2.4)1.2 (0.7–2.1)
 Yes, with others91(35.0)63(24.2)2.2 (1.4–3.4)1.7 (0.9–2.9)
  • * N = 260 matched pairs. Sleep environment data refer to last sleep (cases) and reference sleep period (controls).

  • Statistically significant ORs are indicated in bold.

  • Adjusted for maternal age, marital status, education, and index of prenatal care.