Abstract
Background: The possible relationship between diet-related inflammation and the risk of gestational diabetes mellitus (GDM) requires further investigation, especially in non-Western populations. We examined the association between dietary inflammatory index (DII) scores and GDM in a case-control study conducted in Iran. Methods: This study included 122 GDM cases and 266 controls hospitalized for acute non-neoplastic diseases. Cases were pregnant women aged 18-40 years, who visited major general hospitals in different regions of Tehran. Pregnant women were screened for gestational diabetes between the 24th and 28th week of gestation with a 50-g, 1-hour glucose challenge test (GCT). Cases were diagnosed positive for GDM. Controls were pregnant women who had normal GCT test. DII scores were computed from dietary intake assessed by a previously validated 147-item food frequency questionnaire. Logistic regression models adjusted age, gestational age, energy, exercise, BMI, smoking exposure, family history of diabetes, and history of multivitamin intake were used to estimate odds ratios (ORs) and 95% confidence intervals (CI). Results: Subjects with higher DII scores (i.e. indicating a more proinflammatory diet) had a higher odd of GDM with the DII being used as both a continuous (OR = 1.20; 95% CI = 0.94-1.54) and as categorical (OR(tertile 3vs1) = 2.10; 95% CI = 1.02-4.34, p-trend = .03). Conclusions: These results indicate that a proinflammatory diet, as evidenced by higher DII scores, is associated with increased odds of GDM among Iranian women.