Relationship between urinary iodine concentration and all-cause mortality in individuals with diabetes: An analysis of National Health and Nutrition Examination Survey 2005 - 2018
摘要
Urinary iodine concentration (UIC) is related to prediabetes and diabetes; nevertheless, there is still a dearth of data about the association of UIC with all-cause mortality in diabetics.
ObjectiveTo investigate the connection between UIC and all-cause mortality in diabetics.
MethodsData from NHANES, collected on adult Americans between 2005 and 2018, were used in this investigation. The associations between ln-transformed creatinine-adjusted UIC (urinary iodine/creatinine, UI/Cr) and all-cause mortality in diabetics, as well as in older diabetics with a history of thyroid disease, were analyzed using Cox proportional hazards models and survival curve analysis. Subgroup analyses and interaction tests were conducted to examine variables affecting the association between ln(UI/Cr) and all-cause mortality in people with diabetes. Lastly, the effect of smoking on this association was tested by using restricted cubic spline (RCS).
ResultsA total of 2,141 participants were included in this study. ln(UI/Cr) was significantly associated with a higher risk of all-cause mortality in diabetics in the unadjusted model (HR= 1.38, 95% CI: 1.20 - 1.58, P<0.001), but this association lost significance when confounding variables were considered (P> 0.05). Subgroup analysis revealed that Mexican-Americans and females had a stronger positive connection (P<0.05) between ln(UI/Cr) and the risk of all-cause mortality among diabetics. There was a significant correlation between ln(UI/Cr) and mortality in female smokers with diabetes (95% CI: 1.16 - 2.18, P=0.004). The RCS analysis demonstrated a significant non-linear relationship (P-non-linear= 0.0131). ln(UI/Cr) was significantly and positively associated with all-cause mortality in elderly diabetic individuals with a history of thyroid disease (HR= 1.38, 95% CI: 1.01 - 1.87, P=0.042).
ConclusionIn American individuals with diabetes, our research validates the association between UI/Cr and all-cause mortality. This correlation might offer additional dietary suggestions for the management of individuals with diabetes.