Association between serum uric acid/serum creatinine ratios and lung function in the general American population: National Health and Nutrition Examination Survey (NHANES), 2007-2012

Association between the serum uric acid/serum creatinine ratio and cognitive function in older adults: NHANES in the United States

Cognitive impairment can potentially become a significant health concern in older adults. However, early effective diagnostic methods are still lacking. Therefore, we utilized the NHANES database in the US to investigate the relationship between serum uric acid to serum creatinine (SUA/SCR) ratio and cognitive impairment. In our study, a total of 3874 participants were included (2001-2002, 2011-2014). Weighted t tests or chi-square tests were utilized to analyze the basic characteristics of the population. Weighted logistic regression analysis, smooth-fit curves, threshold effects, and subgroup analysis were conducted to investigate the correlation between the SUA/SCR and cognitive impairment. In this study, the SUA/SCR was significantly lower in individuals with cognitive impairment. The logistic regression model, after adjusting for all covariates, revealed that the Q2-Q4 were 0.65 (95% CI 0.49, 0.86), 0.60 (95% CI 0.40, 0.90), 0.55 (95% CI 0.39, 0.77) respectively. This indicates that participants in the Q4 had a 45% reduced risk of cognitive impairment. Smooth-fit curves and threshold effect analysis revealed a nonlinear relationship between SUA/SCR and cognitive impairment, with a turning point at 4.13. Subgroup analysis showed no statistically significant differences in the relationship between SUA/SCR and cognitive impairment among different subgroups (P > 0.05). Our findings indicate a negative correlation between the SUA/SCR and the risk of cognitive impairment in the population of adults aged 60 and above in the US. This suggests that the SUA/SCR holds promise as a potential indicator for cognitive impairment.

Association between waist circumference and lung function in American middle-aged and older adults: findings from NHANES 2007-2012

PURPOSE

There is a major epidemic of obesity, and many obese patients suffer from respiratory symptoms and disease. However, limited research explores the associations between abdominal obesity and lung function indices, yielding mixed results. This study aims to analyze the association between waist circumference (WC), an easily measurable marker of abdominal obesity, and lung function parameters in middle-aged and older adults using the National Health and Nutrition Examination Survey (NHANES).

METHODS

This study utilized data obtained from the National Health and Nutrition Examination Survey (NHANES) spanning 2007 to 2012, with a total sample size of 6089 individuals. A weighted multiple regression analysis was conducted to assess the relationship between WC and three pulmonary function parameters. Additionally, a weighted generalized additive model and smooth curve fitting were applied to capture any potential nonlinear relationship within this association.

RESULTS

After considering all confounding variables, it was observed that for each unit increase in WC, in males, Forced Vital Capacity (FVC) increased by 23.687 ml, Forced Expiratory Volume in one second (FEV1) increased by 12.029 ml, and the FEV1/FVC ratio decreased by 0.140%. In females, an increase in waist circumference by one unit resulted in an FVC increase of 6.583 ml and an FEV1 increase of 4.453 ml. In the overall population, each unit increase in waist circumference led to a FVC increase of 12.014 ml, an FEV1 increase of 6.557 ml, and a decrease in the FEV1/FVC ratio by 0.076%. By constructing a smooth curve, we identified a positive correlation between waist circumference and FVC and FEV1. Conversely, there was a negative correlation between waist circumference and the FEV1/FVC ratio.

CONCLUSIONS

Our findings indicate that in the fully adjusted model, waist circumference, independent of BMI, positively correlates with FVC and FEV1 while exhibiting a negative correlation with FEV1/FVC among middle-aged and older adults in the United States. These results underscore the importance of considering abdominal obesity as a potential factor influencing lung function in American middle-aged and older adults.

Joint association of serum urate and healthy diet with chronic obstructive pulmonary disease incidence: results from the UK Biobank study

Background: The role of serum urate (SU) levels in the development of chronic obstructive pulmonary disease (COPD) remains a topic of debate, and it is unclear whether a healthy diet can mitigate the impact of SU on COPD risk. The objective of this study is to examine whether and to what extent a healthy diet can reduce the risk of COPD in relation to SU levels. Methods: The cohort analysis included 155 403 participants from the UK Biobank. SU levels were measured at the time of recruitment. A healthy diet score was calculated based on the consumption of vegetables, fruits, fish, processed meats, unprocessed red meat, whole grains, and refined grains. The Cox proportional hazards model was used to analyze the associations between SU levels, a healthy diet score, and the risk of COPD. Results: During a follow-up period of 1 409 969 person-years, 2918 incident cases of COPD were identified. Compared with the lowest SU level group, the hazard ratio (HR) and 95% confidence interval (CI) for COPD were 1.17 (1.03, 1.34) for participants with the highest SU level (hyperuricemia), indicating a positive association. Additionally, a dose-response relationship was observed between SU levels and the incidence of COPD (P-value for overall <0.0001). In the combined effect analysis, compared to individuals with high SU (hyperuricemia) + a low diet score (diet score <4), those with normal SU + a high diet score (diet score ≥4) had a HR (95% CI) of 0.75 (0.65, 0.87) for COPD. Conclusions: In summary, there is a positive association between SU levels and the risk of COPD. Furthermore, a healthier diet can mitigate the risk of COPD associated with high SU levels.

Association between serum uric acid levels and lung function in the NHANES cohort (2007-2012): A cross-sectional analysis of a diverse American population

BACKGROUND

Hyperuricemia has been linked to various health conditions. However, the relationship between uric acid (UA) levels and lung function remains debated.

METHODS

In a cross-sectional study of 6750 participants aged 20-69 from NHANES, we assessed UA levels and lung function (FVC and FEV1). We conducted regression analyses while adjusting for potential confounders.

RESULTS

After accounting for factors like age, sex, BMI, smoking, and more, we found a negative association between UA FVC and FEV1. Specifically, for every 0.1 mg/dL increase in UA, FEV1 decreased by 15.265 mL, and FVC decreased by 24.46 mL. No association was observed with FEV1/FVC. Subgroup analyses revealed similar negative correlations among various groups, particularly in non-Hispanic Black females under 60.

CONCLUSION

Serum UA levels are inversely associated with FEV1 and FVC in the American population, with a notable impact on non-Hispanic Black females under 60.