Table 1

Participant characteristics of adult participants over 30 years of age by HOMA-IR and type 2 diabetes from the 2009–2010 NHANES*

CharacteristicsTotalFull analytic sample 1Analytic subsample 2
Type 2 diabetes§HOMA-IR¶
PresentAbsentHOMA-IR ≥75thInsulin-sensitive
n%n%n%n%n%
Unweighted sample163126212.57136987.4334223.57102776.43
Weighted sample136 081 78117 101 218118 980 56428 039 12690 941 437
Age (years) (%)
 ≥30 to <45 (R)56337.63312.453041.214143.538940.5
 ≥45 to <6571045.012651.858444.014543.643944.0
 ≥65 35817.410335.925514.85612.919915.4
Sex (%)
 Male (R)78848.615157.263747.318555.845244.7
 Female84351.411142.873252.715744.257555.3
Race/ethnicity (%)
 Non-Hispanic white (R)76068.99659.366470.315366.251171.6
 Non-Hispanic black27510.85213.222310.56714.41569.3
 Total Hispanic including multiracial59620.311427.548219.212219.436019.2
Education (%)
 Some college or higher (R)82961.411355.671662.215652.656065.2
 High school diploma36422.36323.430122.18728.521420.1
 Less than high school43316.48521.034815.79818.925014.7
Health insurance (%)
 Yes (R)122581.321585.3101080.724679.076481.3
 No40618.74714.735919.39621.026318.7
PIR (%)
 PIR≥350%= PIR≥3.50 (R)48042.86132.941944.39135.732846.9
 130%≤PIR< 350%=1.30≤ PIR<3.5054933.69738.745232.810433.834832.5
 PIR<130%= PIR<1.3044516.27218.237315.911721.925614.0
 Did not answer (missing)1577.43210.21257.0308.5956.5
BMI (%)
 Normal <25 kg/m2 (R)40527.83512.237030.1175.735337.6
 Overweight ≥25 to <30 kg/m2 58034.07423.850635.59323.941339.1
 Obese ≥30 kg/m2 64038.215264.048834.423170.425723.3
Physical activity (%)
 Active, vigorous-to-moderate (R)92062.411651.980463.918656.461866.0
 Sedentary71137.614648.156536.115643.640933.8
Smoking status (%)
 Former or never smoker (R)133884.122487.8111483.527182.484383.9
 Current smoker29315.93812.225516.57117.618416.1
Serum vitamin D3 (25(OH)D3) status (%)†
 Sufficient levels (R)103970.513558.890472.120060.670475.7
 Insufficient levels (<50 nmol/L)59229.512741.346527.914239.423224.3
Serum vitamin (25(OH)D) status (%)†
 Sufficient levels (R)112575.916571.196076.621766.274379.8
 Insufficient levels (<50 nmol/L)50624.19728.940923.412533.828420.2
Season of examination (%)†
 Summer, May 1–October 3 (R)90361.114361.476061.117357.358762.3
 Winter, November 1–April 3072838.911938.660938.916942.744037.8
Periodontitis (%)‡
 None or mild (R)87260.59038.978263.619161.459164.3
 Moderate or severe75939.517261.158736.415138.643635.7
  • Missing values for analytic samples 1 and 2, respectively: education: n=5 (0.1%) and n=4 (0.14%); BMI: n=6 (0.3%) and n=5 (0.32%).

  • * NHANES survey analytic guidelines recommend the relative SE is not larger than 30%, all estimates for each subgroup were less than 30%.

  • Serum vitamin D (25(OH)D) and vitamin D3 (25(OH)D3) insufficiency is defined as levels <50 nmol/L or <20 ng/mL.

  • Case definitions for periodontitis based on the definition from the Division of Oral Health at the Centers for Disease Control and Prevention, in collaboration with the American Academy of Periodontology.

  • § Type 2 diabetes based on self-report of a previous diagnosis by a physician or other health professionals, or based on the level of hemoglobin A1c of 6.5% (48 mmol/mol) or greater and fasting plasma glucose level of 126 mg/dL or greater.

  • HOMA-IR ≥4.17 (population-specific 75th percentile) established using fasting glucose and insulin levels by the following formula: HOMA-IR=[glucose (mmol/L)×insulin (μU/mL) / 22.5]. HOMA-IR excluded those with diagnosed and undiagnosed type 2 diabetes.

  • 25(OH)D, 25-hydroxyvitamin D; 25(OH)D3, 25-hydroxyvitamin D3; BMI, body mass index; HOMA-IR, homeostatic model assessment for insulin resistance; NHANES, National Health and Nutrition Examination Survey; PIR, poverty income ratio; R, reference category.