Table 3—

Prevalence of GDM detected by NDDG or Carpenter-Coustan diagnostic plasma glucose thresholds by age and ethnicity (KPMCP of Northern California, 1996)

NGDM by NDDG
GDM by Carpenter-Coustan
Percent change
n%(95% CI)n%(95% CI)
Age groups
 <25 years7,469771.0(0.8–1.3)1301.7(1.4–2.0)70.0
 25–29 years7,6092313.0(2.6–3.4)3484.6(4.1–5.0)53.3
 30–34 years7,2153064.2(3.8–4.7)4506.2(5.7–6.8)47.6
 ≥35 years4,1532375.7(4.9–6.4)3448.3(7.4–9.1)45.6
P linear trend<0.001<0.001
All women26,4468513.2(3.0–3.4)1,2724.8(4.5–5.1)50.0
Ethnic groups
 White13,7143462.5(2.3–2.8)5423.9(3.6–4.3)58.3
  Age-adjusted2.4a*(2.2–2.7)3.8a*(3.5–4.1)
 African-American2,345602.6(1.9–3.2)803.4(2.7–4.1)33.3
  Age-adjusted3.0ab*(2.2–3.8)4.0a*(3.1–4.8)
 Hispanic5,0261693.4(2.9–3.9)2484.9(4.3–5.5)46.2
  Age-adjusted3.9b*(3.3–4.5)5.6(4.9–6.3)
 Asian4,1212345.7(5.0–6.4)3418.3(7.4–9.1)48.0
  Age-adjusted5.0(4.4–5.7)7.4(6.6–8.2)
  • *

    * Within each column, different superscript letters among age-adjusted ethnic groups indicate significant pairwise difference at P < 0.0083 for an overall error rate of 0.05 (i.e., within each diagnostic threshold, ethnic groups containing the same superscript letter are not statistically significantly different from each other).