Association of Serum Uric Acid Concentration and Its Change with Cardiovascular Death and All-Cause Mortality

Development of a prediction model to estimate the 5-year risk of cardiovascular events and all-cause mortality in haemodialysis patients: a retrospective study

Background

Cardiovascular disease (CVD) is a major cause of mortality in patients on haemodialysis. The development of a prediction model for CVD risk is necessary to help make clinical decisions for haemodialysis patients. This retrospective study aimed to develop a prediction model for the 5-year risk of CV events and all-cause mortality in haemodialysis patients in China.

Methods

We retrospectively enrolled 398 haemodialysis patients who underwent dialysis at the dialysis facility of the General Hospital of Northern Theater Command in June 2016 and were followed up for 5 years. The composite outcome was defined as CV events and/or all-cause death. Multivariable logistic regression with backwards stepwise selection was used to develop our new prediction model.

Results

Seven predictors were included in the final model: age, male sex, diabetes, history of CV events, no arteriovenous fistula at dialysis initiation, a monocyte/lymphocyte ratio greater than 0.43 and a serum uric acid level less than 436 mmol/L. Discrimination and calibration were satisfactory, with a C-statistic above 0.80. The predictors lay nearly on the 45-degree line for agreement with the outcome in the calibration plot. A simple clinical score was constructed to provide the probability of 5-year CV events or all-cause mortality. Bootstrapping validation showed that the new model also has similar discrimination and calibration. Compared with the Framingham risk score (FRS) and a similar model, our model showed better performance.

Conclusion

This prognostic model can be used to predict the long-term risk of CV events and all-cause mortality in haemodialysis patients. An MLR greater than 0.43 is an important prognostic factor.

High serum uric acid trajectories are associated with risk of myocardial infarction and all-cause mortality in general Chinese population

Background

Long-term patterns of serum uric acid (SUA) and their association with the risk of myocardial infarction (MI) and mortality are poorly characterized as prior studies measured SUA at a single time point. This study aimed to identify SUA trajectories and determine their associations with incident MI and all-cause mortality.

Methods

We included 85,503 participants who were free of MI in or prior 2012 from the Kailuan study. SUA trajectories during 2006–2012 were identified by group-based trajectory modeling. Cox proportional hazard models were used to assess the association of SUA trajectories with MI and all-cause mortality.

Results

We identified three SUA trajectories during 2006–2012: low-stable (n=44,124, mean SUA: 236–249 μmol/L), moderate-stable (n=34,431, mean SUA: 324–354 μmol/L) and high-stable (n=6,984, mean SUA: 425–463 μmol/L). During a median follow-up of 6.8 years, we documented 817 (0.96%) incident MI and 6498 (7.60%) mortality. Compared with the low-stable group, high-stable group experienced a higher risk of MI (hazard ratio [HR], 1.35; 95% confidence [CI], 1.07–1.71) and all-cause mortality (HR, 1.22; 95% CI, 1.12–1.33). Multiple sensitivity analyses yielded similar results. Additionally, the association of SUA trajectory with MI and all-cause mortality was more pronounced in individuals without a history of hypertension (P-interaction=0.0359) and those aged <60 years (P-interaction<0.0001), respectively.

Conclusions

Higher SUA trajectories were associated with altered risk of MI and all-cause mortality, suggesting that monitoring SUA trajectory may assist in identifying subpopulations at higher risk of MI and all-cause mortality.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13075-022-02812-y.

Distinct Prognostic Role of Serum Uric Acid Levels for Predicting All-Cause Mortality Among Chinese Adults Aged 45~75 Years With and Without Diabetes

Introduction

The current study sought to explore the effect of baseline serum uric acid (SUA) on the risk of all-cause mortality among Chinese adults aged 45~75 years and to determine its interaction relationship with diabetes.

Methods

The study was designed as a community-based cohort of 4467 adults aged between 45~75 years included in a 6-years follow-up period from 2009 to 2015 years by the China Health and Nutrition Survey (CHNS). Baseline SUA levels were grouped into quartiles and its association on all-cause mortality was explored using multivariate Cox proportional hazards models. Stratified analyses were performed to explore the associations of SUA quartiles with all-cause mortality among diabetic and non-diabetic individuals.

Results

A total of 141 deaths (5.3 per 1000 person-years) were recorded During a follow-up of 26431 person-years. Out of the 141 deaths, 28 deaths (10.1 per 1000 person-years) were reported in the diabetic groups and 113 deaths (4.8 per 1000 person-years) were recorded in the non-diabetic group. An increased risk of all-cause mortality was observed for participants in the first and fourth quartiles compared with the second SUA quartile, (Q1 SUA: aHR=2.1, 95% CI 1.1~4.1; Q4 SUA: aHR=2.1, 95% CI 1.1~4.0). Stratification of participants by diabetes status showed a U-shaped association for non-diabetic individuals. Whereas, declined eGFR, rather than SUA, was an independent risk factor for all-cause mortality in diabetic individuals (aHR=0.7, 95% CI 0.6~1.0).

Conclusion

Our study proved that the prognostic role of SUA for predicting all-cause death might be regulated by diabetes. Both low and high SUA levels were associated with increased mortality, supporting a U-shaped association only in non-diabetic individuals. Whereas, renal dysfunction rather than SUA was an independent risk factor for all-cause mortality. Further studies should be conducted to determine the SUA levels at which intervention should be conducted and explore target follow-up strategies to prevent progression leading to poor prognosis.

Cumulative Serum Uric Acid and Its Time Course Are Associated With Risk of Myocardial Infarction and All-Cause Mortality

Background Serum uric acid (SUA) has been demonstrated as a risk factor for myocardial infarction (MI) and all-cause mortality; however, the impact of cumulative SUA (cumSUA) remains unclear. We aimed to investigate the association of cumSUA with MI risk and all-cause mortality, and to further explore the effects of SUA accumulation time course. Methods and Results The study enrolled 53 463 participants without a history of MI, and these participants underwent 3 examinations during 2006 to 2010. cumSUA from baseline to the third examination was calculated, multiplying mean values between consecutive examinations by time intervals between visits. Cox models estimated hazard ratios (HRs) and 95% CIs of MI and all-cause mortality for cumSUA quartiles, hyperuricemia exposure duration, and SUA accumulation time course. During a median follow-up of 7.04 years, 476 incident MIs and 2692 deaths occurred. In the fully adjusted model, a higher MI risk was observed in the highest cumSUA quartile (HR, 1.48; 95% CI, 1.10-1.99), in participants with longer hyperuricemia exposure duration (HR, 1.71; 95% CI, 1.06-2.73), and in participants with cumSUA≥median and a negative slope (HR, 1.58; 95% CI, 1.18-2.11). Similar associations persisted for all-cause mortality. Conclusions The risk of MI and all-cause mortality increased with higher cumSUA and was affected by the SUA accumulation time course. Early SUA accumulation contributed more to MI risk and all-cause mortality than later SUA accumulation with the same overall cumulative exposure, emphasizing the importance of optimal SUA control early in life.

Correlation analysis of low-level serum uric acid and cardiovascular events in patients on peritoneal dialysis

Background

The impact of serum uric acid (SUA) on development of cardiovascular disease (CVD) in patients undergoing peritoneal dialysis (PD) remains controversial, especially the impact of hypouricemia (HUA) on CVD. The aim of our study was to investigate the influence of low-level SUA on cardiovascular (CV) events in PD patients.

Methods

A retrospective cohort study was conducted.728 PD patients from February 1, 2010 to May 31, 2019 were enrolled. All demographic and laboratory data were collected at baseline and 6 months after PD treatment. The study cohort was divided into four groups according to SUA level (μmol/L) after 6 months of PD: Group1 (< 360), Group2 (360–420), Group3 (420–480), Group4 (≥ 480). The clinical characteristics of each group were analyzed. With Group2 as reference, logistic regression analysis was performed to investigate the correlation between SUA levels and risk of CV events in patients undergoing PD. Use Kaplan–Meier method to generate CV events risk graph.

Results

728 patients were enrolled in this study, including 403 (55.4%) males and 325 (44.6%) females, with an average age of 48.66 ± 13.98 years; of which 158 (21.7%) patients developed CV events. Multivariate COX regression showed that after adjusting for multiple clinical factors, Group1 (HR = 1.92, 95% CI 1.17–3.15, P = 0.01), Group3 (HR = 1.89, 95% CI 1.13–3.15, P = 0.015), and Group4 (HR = 2.38, 95% CI 1.35–4.19, P = 0.003) are all independent risk factors for developing CV events. The Kaplan–Meier risk curve of CV events showed that the risk of CV events in the Group1, Group3 and Group4 were significantly higher (Log-Rank = 12.67; P = 0.005). Restricted cubic spline (RCS) showed that SUA level is non-linearly associated with the risk of CV events, showing an U-shaped curve (\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\chi_{4}^{2}$$\end{document}χ42=13.3 P = 0.01).

Conclusions

Our study suggested that patients with SUA level less than 360 μmol/L also exhibited the higher risk for developing CV events, an U-shaped association between SUA level and risk of CV events in patients undergoing PD. Both SUA levels below 360 μmol/L and above 420 μmol/L were found to be significant risk factors for developing CV events in patients undergoing long-term PD.

Changes in serum uric acid and the risk of cardiovascular disease and all-cause mortality in the general population

BACKGROUND AND AIM

Longitudinal evidence on change in serum (SUA) with risk of cardiovascular disease (CVD) and all-cause mortality is limited, as many prior studies focused on baseline SUA. Further, the optimal threshold range of SUA change is unclear.

METHODS AND RESULTS

A total of 63,127 participants without history of CVD were enrolled. Change in SUA was determined by the difference of SUA levels between 2006 and 2010, which divided by baseline SUA was percent change in SUA. Multivariable Cox proportional hazards models were used to calculated the hazard ratios (HRs) and 95% confidence intervals (CIs). Our analysis also included restricted cubic spline model and three-piecewise Cox proportion hazards model to address the non-linearity between percent change in SUA and outcomes. During a median follow-up of 7.04 years, 3341 CVD and 3238 deaths occurred. We did not observed a significant association between changes in SUA and CVD. However, changes in SUA at extreme were associated with higher risk of all-cause mortality, the HRs (95% CIs) were 1.15 (1.02-1.29) and 1.20 (1.06-1.35) in the first and fifth quintile group, compared with the third quintile group. We further found a U-shaped association between percent change in SUA and all-cause mortality, and the optimal range was within 20%.

CONCLUSIONS

Changes in SUA at extreme were risk factors for all-cause mortality, but not for CVD in the general population. The findings are relevant for role of SUA in the management of CVD risk and may contribute to improve identification of patients at higher risk.

Visit-to-visit variability of serum uric acid measurements and the risk of all-cause mortality in the general population

Background

Evidence on longitudinal variability of serum uric acid (SUA) and risk of all-cause mortality in the general population is limited, as many prior studies focused on a single measurement of SUA.

Methods

A total of 53,956 participants in the Kailuan study who underwent three health examinations during 2006 to 2010 were enrolled. Variability of SUA was measured using the coefficient of variation (primary index), standard deviation, average real variability, and variability independent of the mean. Cox proportional hazard regressions were used to calculate the hazard ratio (HR) and 95% confidence interval (CI) for the association of variability of SUA with subsequent risk of all-cause mortality, considering its magnitude and the direction and across different baseline SUA categories.

Results

Over a median follow-up of 7.04 years, 2728 participants died. The highest variability of SUA was associated with an increased risk of all-cause mortality, the HR was 1.33 (95% CI, 1.20–1.49) compared with the lowest variability. In this group, both a large fall (HR, 1.28; 95% CI, 1.14–1.44) and rise (HR, 1.18; 95% 1.05–1.32) in SUA were related to risk of all-cause mortality. These associations were similar across different baseline SUA categories. Consistent results were observed in alternative measures of SUA variability. Moreover, individuals with higher variability in SUA were more related to common risk factors than those with stable SUA.

Conclusions

Higher variability in SUA was independently associated with the risk of all-cause mortality irrespective of baseline SUA and direction of variability in the general population.

Uric Acid Variability and All-Cause Mortality: A Prospective Cohort Study in Northern China

OBJECTIVES

Uric acid(UA) is related with cardiovascular disease, but the association of UA variability with all-cause mortality is rarely known. This study aimed to investigate the relationship between UA variability and all-cause mortality in Kailuan cohort study in northern China.

DESIGN

Cohort study.

SETTING

Kailuan community hospitals in Tangshan, Hebei province, Northern China.

PARTICIPANTS

A total of 55717 participants from Kailuan Study were enrolled, and our study followed up biennially from 2006 to 2010.

MEASUREMENTS

Clinical records of the participants enrolled were analyzed. UA variation independent of mean (UAVIM) values were calculated and all the participants were quartile grouped into four groups as: Q1(UAVIM<0.68), Q2(0.68≤UAVIM<1.10), Q3(1.10≤UAVIM<1.67) and Q4(UAVIM≥1.67). The endpoint event was all-cause death. Cox regression model was performed to evaluate the hazard ratios(HRs) of all-cause mortality based on UAVIM groups.

RESULTS

During a median follow-up of 6.83 years, 2926 deaths occurred. The accumulated mortality rates were 4.6%, 4.8%, 5.4% and 6.1% in group Q1, Q2, Q3 and Q4 respectively. When adjusted potential confounders, the highest risk for all-cause mortality was in group Q4 and the adjusted HRs and 95% confidence intervals(CIs) of group Q2-Q4 for all-cause death were 1.044(0.937, 1.164), 1.182(1.064, 1.314) and 1.353(1.220, 1.501) compared with group Q1, respectively. Further analysis showed that the risk for all-cause death increased as UAVIM value increased. Sensitive analysis still showed the similar results when excluding participants with hyperuricemia or severe chronic kidney diseases. Sub-group analysis by age, gender, BMI or hypertension history also indicated analogous results.

CONCLUSION

Elevated UAVIM was related with increased all-cause mortality and UAVIM was an independent risk factor for all-cause mortality in the community cohort study.