The Association between Dietary Inflammatory Index with Sleep Quality
and Obesity among Iranian Female Students: A Cross-sectional Study
Background: Overweight, obesity and lack of sleep quality as
inflammatory states are the common problems among college students and
the Association of Dietary Inflammatory Index (DII) with these problems
among this population is unknown. We aimed to evaluate the relationship
of the DII with obesity and sleep quality among Iranian female students.
Methods: The present cross-sectional study was conducted in 249 female
college students. The Dietary Inflammatory Index (DII) was calculated
using a valid and reliable 147-item food frequency questionnaire (FFQ).
To assess sleep quality, Pittsburgh Sleep Quality Index (PSQI) was used.
Odds Ratio (OR) and 95% Confidence Intervals (CIs) were estimated for
anthropometric indices and sleep quality according to DII score. Linear
regression was used to estimate the relationship between DII score with
sleep and anthropometric indices. Results: There was a significant
association evident between DII and sleep quality(> 5 is
considered as poor quality of sleep); i.e., the odds ratios between DII
quartile 2 vs 1 (unadjusted model: OR= 0.33 (CI: 0.14-0.74), P for trend
=0.002; model 1: the fully adjusted OR= 0.31(CI: 0.12-0.78), P for trend
= 0.005; model 2:OR=0.30 (CI:0.12-0.78), P for trend = 0.005) to
quartile 4(unadjusted model: OR= 1.13(CI: 0.45-2.80); model 1: OR=
1.11(CI: 0.44-2.79); model 2:OR=1.13(CI:0.44-2.87), P for trend =
0.005). Also, odds ratios increased significantly from quartile 2 to
quartile 4 in all models for DII and sleep quality. According to the
continuous score of DII, there was a significant positive association
between DII and sleep quality in all 3 models: unadjusted, model 1, and
model 2 (OR= 1.21 (CI: 1.05-1.40), OR= 1.21 (CI: 1.03-1.43), and OR=
1.22 (CI: 1.03-1.44), respectively. Conclusions: In this study, after
removing the effect of confounding factors, participants in the highest
quartile of DII score had significantly higher PSQI global score.