Table 1—

Sociodemographic and clinical characteristics of youth with type 1 or type 2 diabetes: the SEARCH study prevalent 2001 and incident 2002–2005 cases

Type 1 diabetes
Type 2 diabetes
P
0–45–910–14≥15P*10–14≥15P
Sociodemographic characteristics
    Income0.00360.9565<0.0001
        <$25,00027 (9.8)80 (9.9)116 (9.6)73 (8.6)11 (29.7)20 (31.7)
        $25,000–$49,00078 (28.4)183 (22.6)223 (18.5)168 (19.8)9 (24.3)17 (27)
        $50,000–$74,00071 (25.8)169 (20.9)287 (23.8)190 (22.4)10 (27)14 (22.2)
        ≥$75,00099 (36)376 (46.5)580 (48.1)417 (49.2)7 (18.9)12 (19)
    Education0.01900.74780.0003
        Less than high school1 (0.3)12 (1.4)31 (2.5)11 (1.2)3 (7.1)4 (5.6)
        High school graduate or higher295 (99.7)832 (98.6)1231 (97.5)940 (98.8)39 (92.9)67 (94.4)
    Insurance§<0.00010.0466<0.0001
        Private220 (78.6)637 (81.5)981 (84.6)744 (87)30 (78.9)33 (52.4)
        Medicaid/Medicare54 (19.3)127 (16.2)150 (12.9)78 (9.1)8 (21.1)26 (41.3)
        Other3 (1.1)13 (1.7)13 (1.1)15 (1.8)2 (3.2)
        None3 (1.1)5 (0.6)15 (1.3)18 (2.1)2 (3.2)
Clinical characteristics
    Fasting C-peptide (adjusted means ± SE)0.1 ± 0.040.3 ± 0.020.5 ± 0.020.6 ± 0.02<0.00013.4 ± 0.43.7 ± 0.30.5892<0.0001
    GAD antibody positive115 (55)371 (51.5)618 (54.4)451 (51)0.36906 (15)15 (23.4)0.2970<0.0001
        Duration adjusted (%)46.446.352.959<0.000114.823.60.2981<0.0001
    DKA at onset [n (% yes)]73 (28.9)94 (18.5)143 (24)37 (15.8)0.00073 (8.8)1 (2.6)0.24110.0008
    Family history of diabetes<0.00010.9734<0.0001
        Yes133 (44.8)404 (47.9)714 (56.8)528 (55.1)32 (78)56 (77.8)
        No164 (55.2)439 (52.1)544 (43.2)430 (44.9)9 (22)16 (22.2)
    Diabetes therapy (current)0.00200.7264<0.0001
        Insulin297 (100)835 (99.4)1,245 (98.7)927 (97.1)10 (25)13 (19.1)
        Metformin3 (0.2)2 (0.2)19 (47.5)34 (50)
        Both5 (0.6)12 (1)23 (2.4)8 (20)18 (26.5)
        None1 (0.1)3 (0.3)3 (7.5)3 (4.4)
    A1C<0.00010.3267<0.0001
        < 8%108 (52.7)433 (59.7)622 (53.6)399 (44.7)29 (70.7)52 (80)
        8–9.5%90 (43.9)255 (35.2)408 (35.2)302 (33.8)7 (17.1)5 (7.7)
        ≥9.5%7 (3.4)37 (5.1)130 (11.2)192 (21.5)5 (12.2)8 (12.3)
    BMI z score0.6 ± 10.6 ± 0.90.6 ± 0.90.6 ± 0.90.95541.9 ± 0.82.1 ± 0.60.1331<0.0001
    Weight0.46150.0773<0.0001
        Underweight/normal127 (70.2)575 (69.8)840 (68.2)641 (69.1)7 (17.1)3 (4.7)
        Overweight 85th–95th percentile37 (20.4)148 (18)260 (21.1)194 (20.9)3 (7.3)9 (14.1)
        Obese ≥95th percentile17 (9.4)101 (12.3)131 (10.6)92 (9.9)31 (75.6)52 (81.3)
    High waist circumference**36 (20.8)97 (11.9)162 (13.4)125 (14)0.021433 (78.6)55 (87.3)0.2342<0.0001
    Acanthosis nigricans [n (% yes)]3 (1.6)9 (1.1)26 (2.1)18 (2)0.349916 (43.2)16 (25.8)0.0727<0.0001
    High blood pressure††22 (13.1)41 (5.1)53 (4.4)39 (4.2)<0.000113 (31.7)4 (6.2)0.0005<0.0001
        Duration adjusted (%)12.954.44.30.000130.66.30.0033<0.0001
    Self-reported hypertension6 (0.7)16 (1.3)62 (6.5)<0.000111 (26.8)22 (31.4)0.6089<0.0001
        Duration adjusted (%)0.81.35<0.000126.231.80.5463<0.0001
    High triglycerides (≥110 mg/dl)3 (1.8)26 (4)115 (10.8)204 (25)<0.000121 (56.8)39 (60.9)0.6802<0.0001
        Duration adjusted (%)2.14.41122.1<0.000157.960.40.8147<0.0001
    Low HDL cholesterol (≤40 mg/dl)27 (13.4)45 (6.3)123 (10.7)163 (18.3)<0.000121 (52.5)46 (69.7)0.0751<0.0001
        Duration adjusted (%)11.85.810.320.1<0.000146.774.10.0113<0.0001
    High LDL cholesterol (≥100 mg/dl)91 (53.8)291 (45.3)445 (41.9)369 (45.2)0.027516 (43.2)36 (56.3)0.20760.1654
        Duration adjusted (%)57.947.842.741.30.000644.555.50.30490.0631
    ApoB [median (interquartile range)]75 (17.5)71 (22)71 (23)76 (26)<0.000183 (32)90 (40)0.1049<0.0001
        Duration adjusted [median (interquartile range)]74.8 (0.7)68.3 (2.0)70.1 (3.2)76.4 (5.3)<0.000179.6 (2.3)89.7 (7.1)0.2220<0.0001
    High ACR (≥30)13 (6.9)40 (5.4)112 (10.1)89 (10.8)0.00065 (11.9)9 (15.3)0.63110.0872
        Duration adjusted (%)7.15.610.210.40.003613.312.70.93420.0498
  • Data are n (%), unless otherwise indicated. Physical examination data not collected on youth aged <3 years.

  • *

    * For categorical variables using χ2 test for the association between variable levels and age-groups within type 1 diabetes; for continuous variables using ANOVA for the overall effect of age-group within type 1 diabetes; for adjusted variables using logistic regression (categorical variables) or linear regression (continuous variables) for the overall effect of age-group within type 1 diabetes.

  • For categorical variables using χ2 test for the association between variable levels and age-groups within type 2 diabetes; for continuous variables using ANOVA for the overall effect of age-group within type 2 diabetes; for adjusted variables using logistic regression (categorical variables) or linear regression (continuous variables) for the overall effect of age-group within type 2 diabetes.

  • For categorical variables using χ2 test for the association between variable levels and diabetes type (type 1 versus type 2); for continuous variables using ANOVA for the overall effect of diabetes type (type 1 versus type 2); for adjusted variables using logistic regression (categorical variables) or linear regression (continuous variables) for the overall effect of diabetes type (type 1 versus type 2).

  • §

    § Only nonmembership sites (South Carolina, Ohio, Washington, and Colorado).

  • Incident cases only.

  • Family history includes parents, grandparents, and biological siblings.

  • **

    ** Waist circumference ≥90th percentile for age and sex.

  • ††

    †† Measured blood pressure (systolic or diastolic) ≥ age-, sex-, and height-specific 95th percentile.