Long-term predictive models of risk factors for early chronic kidney disease: a longitudinal study.

BACKGROUND: The high incidence and prevalence of chronic kidney disease (CKD) in Taiwan have produced tremendous burdens on health care resources. The work environment of air force special operations personnel engenders high psychological stress, and the resulting increased blood pressure can lead to glomerular hypertension and accelerated glomerular injury in the long term. The aim of the study was to establish the predictive models to define the predictors of CKD. RESULTS: The results indicated that the prevalence of CKD over 4 consecutive years was 3.8%, 9.4%, 9.0%, and 9.4%. The capability of using occult blood in urine to predict the risk of CKD after 1, 2, and 3 years was statistically significant. The age-adjusted odds ratio (OR) and 95% confidence interval (CI) were 7.94 (95% CI: 2.61-24.14), 12.35 (95% CI: 4.02-37.94) and 4.25 (95% CI: 1.32-13.70), respectively. DISCUSSION: The predictive power of occult blood in urine for the risk of CKD in each model was statistically significant. Future investigations can explore the feasibility of implementing simple and accurate urine dipsticks for preliminary testing besides annual aircrew physical examinations to facilitate early detection and treatment. METHODS: This study was a longitudinal study, in which air force special operations personnel who received physical examinations at military hospitals between 2004 and 2010 were selected. CKD was determined based on the definition provided by the US National Kidney Foundation. Overall, 212 participants that could be followed continuously for 4 years were analyzed.

Elevated uric acid level as a significant predictor of chronic kidney disease: a cohort study with repeated measurements.

BACKGROUND: Cohort studies evaluating increased serum uric acid (SUA) level as a chronic kidney disease (CKD) risk factor have yielded variable results. We aimed to assess the association between the pattern of longitudinal changes in SUA and incident CKD [estimated glomerular filtration rate (eGFR) <60 ml/min/1.73 m(2)]. METHODS: A population-based cohort study was conducted on 3,605 participants who were followed prospectively for a mean of 5.18 years. The longitudinal changes in SUA were categorized into three subgroups: persistently low, fluctuated (reduced or elevated), and persistently high. The primary outcome of interest was the development of CKD at a follow-up examination. Cox proportional hazards analysis was used to test the hypothesis. RESULTS: After adjustment for potential confounders, participants with fluctuated SUA with progressively elevated level and persistently high SUA level had significantly higher risk of developing CKD compared to subjects with persistently low SUA level: adjusted hazard ratio (95% confidence interval) was 2.05 (1.24-3.38) vs. 1.90 (1.34-2.71). This longitudinal relationship was independent of sex, age, body mass index, and hypertension status. CONCLUSIONS: Longitudinally elevated SUA independently predicts the risk of new-onset CKD.

Predictive value of serum apolipoprotein B/apolipoprotein A-I ratio in metabolic syndrome risk: a Chinese cohort study.

The purpose of this study was to evaluate whether the apolipoprotein B/apolipoprotein A-I (apoB/apoA-I) ratio is a promising risk predictor of metabolic syndrome (MetS) and to determine the optimal cut-off value of this ratio in detecting subjects with MetS in a Chinese population. A prospective study was conducted using a representative sample of non-institutionized people in Taiwan. A total of 3,343 participants with mean age (±SD) of 39.86 (±15.61) years old were followed up from 2002 to 2007. The primary outcome was the incidence of MetS. The MetS was defined according to a unified criterion established by several major organizations. There were 462 cases of incident MetS during a mean follow-up period of 5.26 years. A significantly stepwise increase in the incidence of MetS across quartiles of the apoB/apoA-I ratio was noted in both sexes after adjustment for potential confounders (p for trend <0.001). Compared with the lowest quartile of apoB/apoA-I ratio, participants in the highest quartile had a significantly higher risk of MetS in both men [adjusted hazard ratio (HR) = 6.29, 95 % confidence interval (CI) = 2.79-9.13] and women (adjusted HR = 3.82, 95 % CI = 1.06-6.63). Comparisons of receiver operating characteristics curves indicated that the predictive ability of apoB/apoA-I ratio to detect MetS was better than conventional lipid ratio measurements. Furthermore, the optimal cut-off value of apoB/apoA-I ratio for MetS diagnosis was 0.71 in men and 0.56 in women. These results suggest that an elevated apoB/apoA-I ratio might constitute a potentially crucial measure linked to the risk of developing MetS.

Metabolic syndrome and C-reactive protein concentration as independent correlates of chronic kidney disease.

Inflammation is a common phenotype for cardiometabolic disorders. In this study, we attempted to investigate inter-relationships between metabolic syndrome (MetS), C-reactive protein (an inflammatory biomarker) and chronic kidney disease (CKD). We performed a cross-sectional analysis of data from a representative sample of 4425 Chinese adults in Taiwan. The MetS was defined by a unified criteria set by several major organizations. A CKD event was defined as an estimated glomerular filtration rate (eGFR) <60 mL/min per 1.73 m(2). Additionly, a CRP cutpoint of 3 mg/L was used to differentiate high and low CRP levels. Overall, 1000 participants had MetS, resulting in a prevalence rate of 22.6%. High CRP level was noted in 782 (17.6%) subjects. In addition, a total of 508 (11.5%) persons qualified as having CKD. Subjects with the MetS had 1.55-fold [95% confidence interval (CI), 1.03-2.32] increased odds of CKD compared with their counterparts without the MetS after multiple adjustments. In addition, there was a significantly graded relationship between increasing levels of serum CRP and prevalent CKD (p for trend = 0.001). Participants in the highest category of serum CRP had a significantly elevated odds of CKD as compared with those in the lowest category [odds ratio (OR), 1.60; 95% CI, 1.21-2.12]. However, there was no interaction in excess of additive scale between the presence of MetS and high CRP level (p = 0.83). These findings suggest that MetS and high CRP were independently associated with increased prevalence of CKD in Chinese adults.

C-reactive protein concentration as a significant correlate for metabolic syndrome: a Chinese population-based study.

Increasing evidence suggests that chronic, low-grade inflammation may be a common soil involving the pathogenesis of metabolic syndrome (MetS) and cardiovascular disease. We examined the association between C-reactive protein (CRP) concentration, an extensively studied biomarker of low-grade inflammation, and the MetS in a representative sample of Chinese adults in Taiwan. We performed a cross-sectional analysis of data from 4234 subjects [mean (±SD) age, 47.1 (±18.2) years; 46.4 % males] who participated in a population-based survey on prevalences of hypertension, hyperglycemia, and hyperlipidemia in Taiwan. CRP levels were measured by the immunoturbidimetric CRP-latex high-sensitivity assay. The MetS was defined by an unified criteria set by several major organizations. Odds ratios (ORs) and 95 % confidence intervals (CIs) were calculated with logistic regression model. Overall, there were 938 subjects with MetS among 4,234 participants, resulting in a prevalence rate of 22.1 %. A significantly progressive increase in the prevalence of MetS across quartiles of CRP was observed (p for trend <0.001). Participants in the second, third, and upper quartiles of CRP had significantly higher risk of having MetS when compared with those in the lowest quartile [adjusted ORs (95 % CIs) were 2.18 (1.62-2.94), 4.39 (3.31-5.81), and 7.11 (5.39-9.38), respectively; p for trend <0.001]. Furthermore, there was a strong stepwise increase in CRP levels as the number of components of the MetS increased. The prevalence of MetS showed a graded increase according to CRP concentrations. The possible utility of CRP concentration as a marker for MetS risk awaits further evaluation in prospective studies.

Impact of metabolic syndrome on the incidence of chronic kidney disease: a Chinese cohort study.

AIM: Metabolic syndrome (MetS) is a major culprit in cardiovascular disease and chronic kidney disease (CKD) in Western populations. We studied the longitudinal association between MetS and incident CKD in Chinese adults. METHODS: A cohort study was conducted in a nationally representative sample of 4248 Chinese adults in Taiwan. The MetS was defined according to a unified criteria set by several major organizations and CKD was defined as an estimated glomerular filtration rate (eGFR) < 60 mL/min per 1.73 m(2). Cox proportional hazards regression was used to estimate hazard ratios (HR) and 95% confidence intervals (CI) adjusted for sex, age, body mass index (BMI) and serum levels of total cholesterol. RESULTS: The prevalence of MetS among participants at baseline recruitment was 15.0% (637/4248). During a median follow-up period of 5.40 years, 208 subjects (4.9%) developed CKD. The multivariate-adjusted HR of CKD in participants with MetS compared with those without was 1.42 (95% CI = 1.03, 1.73). Additionally, there was a significantly graded relationship between the number of the MetS components and risk of CKD. Further, the relation between MetS and incident CKD was more robust in subjects with BMI >27.5 kg/m(2) than in those with lower BMI. CONCLUSION: The results suggest that the presence of MetS was significantly associated with increased risk of incident CKD in a Chinese population. These findings warrant future studies to test the impact of preventing and treating MetS on the reduction of the occurrence of CKD.