Table 3

Logistic regression models assessing the joint effect of serum vitamin D3 (25(OH)D3) levels and periodontitis with HOMA-IR, pre-diabetes, and type 2 diabetes among adults over 30 years of age from the 2009–2010 NHANES

OutcomesHOMA-IR*Pre-diabetes†Type 2 diabetes‡
ExposuresWith/without outcome§ (n)OR (95% CI)With/without outcome§ (n)OR(95% CI)With/without outcome§ (n)OR (95% CI)
G=0 (periodontitis none or mild)E=0 25(OH)D3 sufficiency112/406Reference (1.00)261/257Reference (1.00)48/518Reference (1.00)
E=1 25(OH)D3 insufficiency¶79/185 1.87 (1.40 to 2.49)** 146/1181.06 (0.71 to 1.60)42/2641.37 (0.58 to 3.33)
G=1 (periodontitis moderate or severe) ††E=0 25(OH)D3 sufficiency88/2981.03 (0.70 to 1.59)269/1171.19 (0.80 to 1.78)87/3861.26 (0.68 to 2.35)
E=1 25(OH)D3 insufficiency¶63/138 1.90 (1.46 to 3.16)** 141/601.23 (0.69 to 2.18)85/201 3.02 (1.30 to 6.98)**
P values‡‡0.960.910.21
With/without outcome§§ (n) With/without outcome§§ (n) With/without outcome§§ (n)
G=0 (periodontitis none or mild)E=0 25(OH)D3 sufficiency112/406Reference (1.00)261/257Reference (1.00)48/518Reference (1.00)
E=1 25(OH)D3 insufficiency¶79/1851.36 (0.94 to 1.95)146/1180.90 (0.61 to 1.34)42/2641.07 (0.48 to 2.38)
G=1 (periodontitis moderate or severe)††E=0 25(OH)D3 sufficiency88/2981.06 (0.62 to 1.83)269/1171.14 (0.73 to 1.77)87/3861.27 (0.70 to 2.28)
E=1 25(OH)D3 insufficiency¶63/1381.57 (0.97 to 2.55)141/600.99 (0.58 to 1.68)85/201 2.83 (1.34 to 5.96)**
P values‡‡0.750.900.10
  • *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.

  • †Pre-diabetes based on the level of HbA1c of 5.7%–6.4% (39–47 mmol/mol), fasting plasma glucose level of 100–125 mg/dL, or adults who reported having been told by a health professional that they have any of the following: pre-diabetes, impaired fasting glucose, impaired glucose tolerance, or borderline diabetes. Pre-diabetes excluded those with diagnosed and undiagnosed type 2 diabetes.

  • ‡Type 2 diabetes based on self-report of a previous diagnosis by a physician or other health professionals, or based on the level of HbA1c of 6.5% (48 mmol/mol) or greater and fasting plasma glucose level of 126 mg/dL or greater.

  • §Minimally adjusted model for age, sex, race/ethnicity, PIR, season, smoking, and physical activity.

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

  • **Significance at p<0.05. Statistically significant values are shown in bold.

  • ††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.

  • ‡‡Represents multiplicative interaction p value results from adjusted survey logistic models.

  • §§Fully adjusted model for age, sex, race/ethnicity, education, insurance, season, smoking, physical activity, and body mass index.

  • 25(OH)D3, 25-hydroxyvitamin D3; HbA1c, hemoglobin A1c; HOMA-IR, homeostatic model assessment for insulin resistance; NHANES, National Health and Nutrition Examination Survey.