Table 1

Sample characteristics of unmatched factors by case status

All patientsCase subjectsControl subjectsP*
n1,990995995
Insulin regimen
 Glargine630 (31.7)38.125.2<0.001
 NPH316 (15.9)22.49.3
 Lispro and/or regular only566 (28.4)19.537.4
 None478 (24.0)20.028.0
Basal-to-total insulin dose ratio
 0.00566 (28.4)19.537.4<0.001
 0.01–0.3999 (5.0)4.55.4
 0.40–0.59267 (13.4)16.310.6
 0.60–1.00580 (29.1)39.718.6
 No insulin478 (24.0)20.028.0
SSI use
 SSI only503 (25.3)16.634.0<0.001
 SSI plus scheduled insulin737 (37.0)42.931.2
 No SSI750 (37.7)40.534.9
Medication use in hospital
 Metformin417 (54.3)49.958.80.086
 Sulfonylureas254 (32.8)35.730.3
 Thiazolidinediones97 (12.6)14.410.8
 Glucocorticoids210 (10.6)10.211.00.558
Weight (kg)85.6 ± 27.085.2 ± 27.786.1 ± 26.20.301
Race
 African American799 (40.6)41.839.40.167
 White671 (34.1)32.236.0
 Hispanic274 (13.9015.112.7
 Other225 (11.4)11.011.9
Laboratory studies
A1C (%)8.1 ± 2.28.0 ± 2.18.1 ± 2.30.438
Albumin (g/dL)3.5 ± 0.63.4 ± 0.63.5 ± 0.5<0.001
Alanine aminotransferase (units/L)34.6 ± 99.334.6 ± 101.234.5 ± 97.40.867
Aspartate aminotransferase (units/L)41.3 ± 219.940.1 ± 172.942.6 ± 260.70.937
Creatinine (mg/dL)1.5 ± 1.71.7 ± 2.01.3 ± 1.2<0.001
Hematocrit (%)32.8 ± 5.232.1 ± 5.033.6 ± 5.3<0.001
WBC (k/UL)8.4 ± 4.18.4 ± 4.48.5 ± 3.70.553
Fasting within prior 24 h403 (20.3)50.649.40.774
Primary service
 Medicine1,40473.568.10.008
 Surgery58026.531.9
Comorbidity index
 0107 (5.40)4.66.1<0.001
 1–2803 (40.4)36.444.3
 3–4682 (34.3)36.432.2
 5–6282 (14.2)17.311.1
 >6116 (5.8)5.36.3
Length of stay (days)7.6 ± 7.08.1 ± 8.27.1 ± 5.5<0.001
  • Data are n (%), percentages, or means ± SD.

  • *P values for categorical variables were generated by χ2 tests. P values for continuous variables were generated by t tests.

  • †Hypoglycemia prevalence among patients who received lispro was similar to that among patients given regular insulin (31.8 vs. 36.1%).

  • ‡Excludes six patients with missing values.