Association Between Dietary Selenium Intake and Chronic Obstructive Pulmonary Disease: A Cross-Sectional Study from the National Health and Nutrition Examination Survey 1999-2018

Abstract

Background: Chronic obstructive pulmonary disease (COPD) is a widespread respiratory condition characterized by chronic inflammation. Selenium, an essential trace element, possesses anti-inflammatory and antioxidant properties. However, the diet is often complex, and the absence of one nutrient may indicate a concurrent deficiency in others. Therefore, inadequate dietary selenium intake may suggest deficiencies in other elements. Despite its potential benefits, there is a scarcity of evidence regarding the association between dietary selenium intake and COPD.

Purpose: This study aims to investigate the potential association between dietary selenium intake and COPD among American adults.

Patients and methods: This cross-sectional study analyzed data from the National Health and Nutrition Examination Survey conducted in the United States from 1999 to 2018. Multivariate logistic regression, restricted cubic spline analyses, subgroup analysis, and sensitivity analysis were conducted to assess the correlation between dietary selenium intake and COPD.

Results: A total of 39,654 participants were included in the study. The adjusted odds ratio (OR) for COPD in the highest selenium intake group (T3, > 122.0 μg/day) was 0.80 (95% CI: 0.71-0.91, p < 0.001) compared to the lowest intake group (T1, < 81.6 μg/day). Dietary selenium intake exhibited a linear negative correlation with COPD. Among participants reporting selenium supplementation, a similar negative association persisted.

Conclusion: This study observed a negative correlation between dietary selenium intake and COPD among American adults, indicating a possible association between higher selenium intake and a lower risk of COPD.

Keywords: COPD; NHANES; National Health and Nutrition Examination Survey; chronic obstructive pulmonary disease; cross-sectional study; dietary selenium intake.

Figure 1

Flowchart depicting the screening and enrollment process for study participants.

Figure 2

Restricted cubic spline plot between dietary selenium intake and odds ratio of COPD. The bar chart illustrates the distribution of the population. Solid and dashed lines denote predicted values with 95% confidence intervals. Reference.point, the median selenium intake. Data represents 99% of the sample. Adjusted for age, sex, race/ethnicity, marital status, education level, body mass index, ratio of income to poverty, physical activity, smoking and drinking status, hypertension, diabetes, total energy intake.

Figure 3

Forest plot illustrating the multivariable-adjusted association between dietary selenium intake and COPD. Each square represents the OR, and the horizontal lines represent the 95% CI. The top of the plot represents the overall summary estimate. Adjustments were made for age, sex, race/ethnicity, marital status, education level, body mass index, ratio of income to poverty, physical activity, smoking and drinking status, hypertension, diabetes, total energy intake.