Association between dietary index for gut microbiota and hypertension: a large cross-sectional study from NHANES

Background: Gut microbiota is strongly associated with hypertension. The Dietary Index of Gut Microbiota (DI-GM) is a newly proposed indicator of the diversity of gut microbiota in the diet. However, the relationship between DI-GM and hypertension is unclear. Methods: Data for this study were obtained from the National Health and Nutrition Examination Survey (2007-2020). Dietary data were used to calculate DI-GM and grouped into three tertile groups. Survey logistic regression and restricted cubic spline (RCS) were used to analyse the association between DI-GM and hypertension. Results: A total of 20 804 participants (age ≥20 years) were enrolled in the study. After adjusting for all covariates, the ORs for hypertension in the medium DI-GM group (second quartile, 4-5) and high DI-GM group (third quartile, >5) were 0.94 (95% CI: 0.83 to 1.06) and 0.87 (95% CI: 0.76 to 0.99) compared with the low DI-GM group (first quartile, <4). Additionally, results from the RCS analysis indicated a linear association between DI-GM and hypertension (p value for non-linearity=0.57). Conclusion: Our findings suggest that higher DI-GM dietary patterns are associated with a lower prevalence of hypertension in a representative sample of US adults. These results suggest that dietary patterns characterised by a higher DI-GM may represent a potential strategy for the prevention of hypertension.