Noninvasive Central Systolic Blood Pressure Is More Strongly Related to Kidney Function Decline Than Peripheral Systolic Blood Pressure in a Chinese Community-Based Population

The relationship between carotid intima-media thickness and carotid plaque: a cohort study in China

Both carotid intima-media thickness (cIMT) and carotid plaque (CP) quantified by B-mode ultrasound have been proposed as surrogate imaging biomarkers of subclinical atherosclerosis, while the relationship between cIMT and CP, whether cIMT evaluation in a given patient might allow for predicting the development of a carotid plaque, is still discussed controversially. We investigated the cross-sectional relationship between cIMT and CP, and the predictive value of cIMT for incident CP formation in 1078 subjects with mean age of 52 ± 5 years in a community based atherosclerosis cohort in Beijing. Participants underwent ultrasonography of bilateral carotid arteries and received vascular risk factor assessment at baseline and after a mean of 2.35 years follow-up. The prevalence of plaque was increased by 3.75-fold for upper quartile cIMT compare with the lower quartile even after adjustments for traditional risk factors at baseline. Among the 746 plaque-free subjects at baseline, 230 (31.0%) developed new CP. After adjusted for demographics and vascular risk factors, neither baseline cIMT nor the cIMT change from baseline to follow-up predicted incident CP. In conclusion, although cIMT associates with CP cross-sectionally, increased cIMT dose not independently predict future plaque development. Our data suggest that paying attention to the traditional risk factors might prevent subjects from developing carotid plaques regardless from IMT changes.

Increased cardio-ankle vascular index is independently associated with chronic kidney disease: A cross-sectional study in Chinese patients with type 2 diabetes mellitus

AIMS

This cross-sectional study aimed to investigate the association between arterial stiffness and chronic kidney disease (CKD) in Chinese patients with type 2 diabetes mellitus (T2DM).

METHODS

This study included 1025 patients with T2DM (796 men, 229 women). The cardio-ankle vascular index (CAVI) served as an index to evaluate arterial stiffness. CKD was defined as an estimated glomerular filtration rate < 60 mL/min/1.73 m² and/or urinary albumin-creatine ratio ≥ 30 mg/g. Increased CAVI was defined as a value ≥9.

RESULTS

The mean CAVI was 8.4 ± 1.2. Among the patients, 314 (40%) had increased CAVI and 229 (22.3%) had CKD. Blood pressure, HbA1c levels, total cholesterol, low-density lipoprotein cholesterol, uric acid and CAVI were higher among patients with CKD than among those without CKD. Patients with increased CAVI were at a 1.82-fold (95% CI, 1.20-2.75; P < 0.001) higher prevalence of CKD after adjusting for other variables. The odds ratio for CKD was 2.69 (95% CI, 1.12-6.47; P = 0.027) in women and 1.62 (95% CI, 1.01-2.61; P = 0.045) in men.

CONCLUSION

Increased CAVI was independently associated with CKD in patients with T2DM. Further longitudinal studies with large sample sizes are warranted to investigate the effect of CAVI on CKD in patients with T2DM.

Elite athletes as research model: vitamin D insufficiency associates with elevated central blood pressure in professional handball athletes

PURPOSE

Low vitamin D levels have been associated with elevated blood pressure in the general population. Prospective studies, however, have produced conflicting evidence about the blood pressure-lowering effects of vitamin D supplementation. Cardiorespiratory fitness may modulate the vitamin D-blood pressure association. We therefore examined this association in professional athletes, whose high training load serves as a biological control for physical fitness.

METHODS

50 male professional handball players (age 26 ± 5 years) were examined. We assessed the central aortic pressure parameters using transfer function-based analysis of oscillometrically obtained peripheral arterial waveforms. Serum 25-OH vitamin D concentrations were determined by chemiluminescent immunoassay. The threshold for insufficiency was set at values of < 30 ng/mL.

RESULTS

Central blood pressure (cBP) was 98 ± 7/60 ± 10 mmHg. The aortic pulse wave velocity (PWV) was 6.3 ± 1.0 m/s. Nine athletes (18%) displayed insufficient 25-OH vitamin D levels and had a significantly (p < 0.01) higher cBP compared with the 41 (82%) athletes with sufficient 25-OH vitamin D levels (106 ± 5/68 ± 8 vs. 97 ± 7/58 ± 9 mmHg). Central systolic blood pressure (cSBP) in vitamin D-sufficient athletes was significantly lower in comparison to the healthy reference population (97 mmHg vs. 103 mmHg, p < 0.001). This significance of difference was lost in vitamin D-insufficient athletes (106 mmHg vs. 103 mmHg, p = 0.12).

CONCLUSION

Significantly raised central systolic and diastolic blood pressure in vitamin D-insufficient elite athletes implicates vitamin D as a potential modifier of vascular functional health.

Serum Lipids and Risk of Rapid Renal Function Decline in Treated Hypertensive Adults With Normal Renal Function

BACKGROUND

We aim to evaluate the effect of different lipids parameters, including triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), the TG to HDL-C (TG:HDL-C) ratio, total cholesterol (TC), and low-density lipoprotein cholesterol (LDL-C), on the risk of rapid renal function decline and examine any possible effect modifiers in general hypertensive patients with normal renal function.

METHODS

A total of 12,549 hypertensive patients with estimated glomerular filtration rate (eGFR) ≥60 ml/min/1.73 m2 in the renal sub-study of the China Stroke Primary Prevention Trial were included in the analyses. The primary outcome was rapid renal function decline, defined as an average decline in eGFR ≥ 5 ml/min/1.73 m2 per year.

RESULTS

The median treatment duration was 4.4 years. After the full adjustment for TC, TG, HDL-C, and other major covariates, a significantly higher risk of rapid renal function decline was found in participants with higher TG [≥150 vs. <150 mg/dl, 7.7% vs. 5.5%; odds ratios (OR): 1.27; 95% confidence interval (CI): 1.06-1.51], higher TG:HDL-C ratio [≥2.7 (median) vs. <2.7, 7.7% vs. 5.0%; OR: 1.39; 95% CI: 1.14-1.71), lower TC (≥200 vs. <200 mg/dl, 6.0% vs. 7.0%; OR: 0.79; 95% CI: 0.67-0.93), or lower LDL-C levels (≥130 vs. <130 mg/dl, 6.1% vs. 7.0%; OR: 0.79; 95% CI: 0.67-0.94). Moreover, the increased risk of the primary outcome associated with elevated TG was particularly evident among individuals with lower total homocysteine levels [<12.4 (median) vs. ≥ 12.4 μmol/l, P interaction = 0.036].

CONCLUSIONS

Higher TG and TG:HDL-C ratio were independent risk factors for rapid renal function decline in hypertensive adults with normal renal function.

U-shaped association between serum albumin and development of chronic kidney disease in general hypertensive patients

BACKGROUND & AIMS

We aimed to examine the association between serum albumin (SAlb) and the development of chronic kidney disease (CKD), and examine any possible effect modifiers in general hypertensive patients with normal renal function and with no previous cardiovascular diseases (CVD).

METHODS

This is a post-hoc analysis (performed at May, 2018) of 12,621 hypertensive adults with estimated glomerular filtration rate (eGFR) ≥60 mL/min/1.73 m² and SAlb ≥35.0 g/L from the renal sub-study of the China Stroke Primary Prevention Trial (CSPPT), conducted from May 2008 to August 2013. The primary outcome was development of CKD, defined as a decrease in eGFR of ≥30% and to a level of <60 mL/min/1.73 m²; or end stage renal disease.

RESULTS

The median follow-up duration was 4.4 years. Overall, the association between SAlb levels and risk of the primary outcome followed a U-shape. The risk of CKD development significantly decreased with the increment of SAlb (per g/L: OR = 0.92; 95% CI: 0.88-0.96) in participants with SAlb <51.4 g/L, and increased with the increment of SAlb (per g/L: OR = 1.06; 95%CI: 1.01-1.11) in participants with SAlb ≥51.4 g/L. Moreover, in participants with SAlb <51.4 g/L, the association between SAlb and CKD development remained significant in participants without proteinuria (per g/L: OR = 0.93; 95% CI: 0.88-0.99). The association between SAlb and CKD development was not significantly modified by age, sex, folic acid treatment, proteinuria, systolic blood pressure (SBP) at baseline and time-averaged SBP during the treatment period (all P-interactions>0.05).

CONCLUSIONS

There was a U-shaped association between SAlb levels and risk of CKD development among general hypertensive patients with normal renal function and without CVD, with a turning point at about 51.4 g/L.

Higher blood pressure increases arterial stiffness modified by blood glucose levels in a Chinese community-based study

Background: Increased arterial stiffness measured by brachial-ankle pulse wave velocity is associated with cardiovascular disease. However, the rates at which brachial-ankle pulse wave velocity and blood glucose accelerate within individuals who differ in blood pressure levels are largely unknown. Methods: This study was based on the baseline data of a Chinese community-based atherosclerosis cohort which included 7402 individuals. Using generalized linear regression models, the relationship between blood glucose levels and brachial-ankle pulse wave velocity, and the relationship between blood pressure levels and brachial-ankle pulse wave velocity were examined. Results: A marked interaction between hypertensive state and diabetic state was seen for brachial-ankle pulse wave velocity (P for interaction <0.001). The adjusted coefficient for subjects stratified by hypertensive groups and diabetic states showed that the highest brachial-ankle pulse wave velocity risk subjects were those who had both diabetes and hypertension (B=403.24; 95% CI: 372.43-434.05; P<0.001). Conclusions: The participants with increased arterial stiffness demonstrate a high prevalence of higher blood pressure. When high blood glucose levels co-occur with high blood pressure levels, there is a remarkable increase in arterial stiffness.

Decreased GFR and its joint association with type 2 diabetes and hypertension with prevalence and severity of carotid plaque in a community population in China

BACKGROUND

Type 2 diabetes (T2DM), hypertension and kidney dysfunction are known risk factors for cardiovascular disease, but their combined effect on carotid plaque remains uncertain. This study aims to assess the associations between T2DM, hypertension, kidney dysfunction and carotid plaque, and further explore the combined effect of three diseases.

PATIENTS AND METHODS

We conducted a cross-sectional analysis among 3,815 community-dwelling adults in a Chinese atherosclerosis cohort. Estimated glomerular filtration rate (eGFR), hypertension and T2DM were evaluated as risk factors for carotid plaque. The presence, number and total area of carotid plaques were also assessed. Using logistic model, mutinomial logistic model and generalized linear regression model, the relationship between risk factors and carotid plaque was examined.

RESULTS

T2DM, hypertension, decreased GFR, and, inversely, eGFR, were independently associated with the presence, number and total area of carotid plaque. Stratified analysis by T2DM and hypertension showed T2DM attenuated the association between eGFR change and carotid plaque. There was a cumulative relationship between three risk factors and carotid plaque burden. The OR for the number of plaques was 1.0 (reference), 1.55 to 2.03, 1.94 to 3.14, and 3.69 (all P<0.05), respectively, for individuals with none, one, two, and three risk factors. Likewise, combining three risk factors was associated with greater increase in total plaque area (β, 20.63; 95% CI, 14.04-27.22).

CONCLUSION

The coexistence of decreased GFR, diabetes and hypertension is associated with increased risk of carotid plaque, and these comorbidities may contribute additively to the development of plaque.

Central aortic pressure improves prediction of cardiovascular events compared to peripheral blood pressure in short-term follow-up of a hypertensive cohort

Objective: The aim of this study was to assess indices of a comprehensive panel of central aortic pressure and arterial stiffness for prediction of cardiovascular events in a hypertensive cohort.Methods: Noninvasive measurements of central aortic blood pressure, brachial pressure, wave reflection augmentation index, pressure amplification, pulse wave velocity (PWV) and carotid intima-media thickness (IMT) were obtained in 675 hypertensive patients (age 61 ± 9 years, 425 males) for a mean follow-up period 25 ± 4 months. The primary endpoints were defined as cardiovascular disease (CVD) events or death from CVD.Results: After adjusting for confounding factors, central systolic (cSBP) and pulse pressure (cPP) showed higher hazard ratios (HR/10 mmHg) for cardiovascular events (CV) compared to peripheral pressure indices (pSBP, pPP) at age >60 years (cSBP: HR = 1.18, pSBP: HR = 1.17, p = 0.034; cPP: HR = 1.28, pPP: HR = 1.2, p = 0.019). Each SD increase in IMT and in central augmented pressure (cAP) entailed a 1.4 times higher risk of increased total events in elderly patients (age >60 years). For males, each SD increase in cAP was associated with 1.36 times higher risk of increased total events. For females, each SD increase in cAIx and cAP was associated with 0.4 and 0.5 times lower risk of increased total and major CV, respectively. This sex difference is most likely due to lack of age-related increase of cAIx in females after age >60 years compared to males.Conclusions: Central pressure improved prediction of CVD compared to peripheral pressure during a relatively short-term follow up of approximately 2 years at age >60 years.

Association of different glucose traits with kidney function decline risk in a Chinese community-based population without chronic kidney disease

Background

Chronic kidney disease (CKD) has become a major issue worldwide and hyperglycemia is known as an important risk factor responsible for CKD progression. Few studies have investigated whether fasting plasma glucose (FPG) could predict kidney function decline (KFD) risk better than postprandial plasma glucose, and vice versa. In this study, we investigated the roles of FPG and 2-hour plasma glucose (2 h-PG) in predicting KFD risk in a Chinese community-based population without baseline deterioration of kidney functions.

Methods

Subjects with normal kidney function from an atherosclerosis cohort in Beijing, China were followed up for 2.3 years. The outcome was KFD (a drop in glomerular filtration rate category accompanied by 25% or greater decline of estimated glomerular filtration rate from the baseline or a sustained decline of more than 5 mL/min/1.73 m²/year rate).

Results

A total of 3,738 subjects were included of which, 7.7% of the subjects suffered from KFD. After covariates adjustments, both FPG (OR =1.23, P<0.001) and 2 h-PG (OR =1.07, P<0.001) were associated with KFD. Furthermore, FPG was independent of 2 h-PG to predict KFD (OR =1.26, P<0.001). Subgroup analyses and interaction tests including diabetes mellitus, after adjusting all covariates, revealed no significant heterogeneity among analyzed subgroups. We also found subjects with FPG level of 6.1–7.0 mmol/L and >7.0 mmol/L had 1.83 times and 2.51 times KFD risk respectively, compared to subjects with FPG level <5.6 mmol/L.

Conclusion

FPG was superior to 2 h-PG in predicting KFD in a Chinese community-based population without CKD. FPG screening may be an important measure for CKD primary prevention even in subjects with impaired fasting glucose.

Brachial-Ankle Pulse Wave Velocity is Associated with the Risk of New Carotid Plaque Formation: Data from a Chinese Community-based Cohort

Artery stiffness is an independent marker for atherosclerotic cardiovascular diseases. However, whether the brachial-ankle pulse wave velocity (ba-PWV) is related to new carotid plaque formation is unresolved. This study aimed to investigate the association between baseline ba-PWV and new carotid plaque formation in a Chinese community-based population without carotid plaques at baseline. This study population consisted of a total of 738 participants from an atherosclerosis cohort in Beijing, China. After a mean 2.3-year follow-up, the incidence of carotid plaques were 21.2% and 36.5% in the groups with ba-PWV < 1,400 cm/s and ≥1,400 cm/s, respectively. Compared with baseline ba-PWV < 1,400 cm/s group, ba-PWV ≥ 1,400 cm/s group was significantly associated with the incidence of new carotid plaque formation (odds ratio [OR] = 2.14, 95% CI: 1.50–3.03, P < 0.01), even after adjusting for common risk factors (OR = 1.52, 95% CI: 1.02–2.25, P = 0.04). Furthermore, there was a strong relationship between baseline ba-PWV and carotid plaque formation in subjects with ba-PWV < 1,400 cm/s, but no such relationship was found in subjects with baseline ba-PWV ≥ 1,400 cm/s. In conclusion, this study suggests that baseline ba-PWV is independently associated with the risk of carotid plaque formation in a Chinese community-based population.

Longer time spent in bed attempting to sleep is associated with rapid renal function decline: the Dongfeng-Tongji cohort study

INTRODUCTION

Prospective evidence on the relation between time in bed and renal dysfunction remains limited. We aimed to investigate the association of time spent in bed attempting to sleep (TSBS) with renal function decline in a middle-aged and elderly Chinese population.

METHODS

About 16,733 eligible participants with a mean age of 62.3 years at baseline were included. Rapid renal function decline was defined as (baseline eGFR - revisit eGFR)/years of follow-up ≥5 mL/min per 1.73 m²/year. A total of 1738 study participants experienced rapid renal function decline after a median 4.6-year follow-up. Logistic regression models were used for multivariate analyses.

RESULTS

The adjusted odds ratio (OR) of rapid renal function decline was 1.18 (95% CI: 1.02, 1.37) for TSBS ≥9 h/night compared with TSBS 7 to <8 h/night. This association remained significant (OR = 1.19, 95% CI: 1.03, 1.38) after further adjustment for sleep quality, midday napping and usage of sleeping pills. Particularly, the association appeared to be prominent in individuals with diabetes.

CONCLUSIONS

Longer TSBS (≥9 h) was independently associated with an increased risk of rapid renal function decline. Our findings emphasized the importance to have optimal TSBS. Key messages Our study firstly investigated the association between time spent in bed attempting to sleep (TSBS) and renal dysfunction in Chinese adults. Compared with individuals TSBS 7 to <8 h, individuals with TSBS ≥9 h had 19% increased risk for rapid renal function decline after adjustment for multivariate confounders. The association appeared to be prominent in individuals with diabetes.

Joint Effect of Non-invasive Central Systolic Blood Pressure and Peripheral Systolic Blood Pressure on Incident Hypertension in a Chinese Community-based Population

Central blood pressure level is not always consistent with peripheral blood pressure level, and especially their joint effect on incident hypertension is not well established. A total of 1607 non-hypertensive subjects from an atherosclerosis cohort in Beijing, China were included. Central systolic blood pressure (cSBP) was obtained using Omron HEM-9000AI machine and peripheral systolic blood pressure (pSBP) was measured using Omron HEM-7117 electronic sphygmomanometer, separately. Hypertension was defined as BP ≥ 140/90 mmHg or self-reported hypertension or taking any antihypertension drugs at the follow-up survey. After a median follow-up of 2.3 years, incident hypertension was 13.1%. Every 1 standard deviation increase of cSBP and pSBP was associated with 1.98 (95%CI: 1.69-2.33) and 2.84 (95%CI: 2.30-3.52) times of incident hypertension after adjustment for confounders. Moreover, hypertension risk in single pSBP ≥ 120 mmHg group, single cSBP ≥ 120 mmHg group, and both pSBP and cSBP ≥ 120 mmHg group was 2.83 (95%CI: 0.98-8.16), 3.28 (95%CI: 1.24-8.70), and 11.47 (95%CI: 4.97-26.46) times higher than both pSBP and cSBP < 120 mmHg group, respectively. The joint effect of cSBP and pSBP is superior to either cSBP or pSBP to predict incident hypertension in a Chinese community-based population. Screening of central blood pressure should be considered in non-hypertensive population for the purpose of primary intervention, especially for subjects with pSBP ≥ 120 mmHg.

Association between short sleep duration and carotid atherosclerosis modified by age in a Chinese community population

Background and aim

Short sleep duration is a risk factor of cardiovascular disorder; however, the association between short sleep duration and carotid atherosclerosis has not been completely characterised. The aim of this study is to investigate the association between short sleep duration and carotid atherosclerosis.

Methods

We used the cross-sectional data collected between May 2014 and July 2014, which were based on a cardiovascular disease cohort study including 3798 participants aged 40 years and older who are residents of Beijing, China. We used logistic regression models to examine the associations between sleep duration and carotid atherosclerosis.

Results

After the adjustment of covariates, short sleep duration (less than 5 hours per night) was found to be associated with carotid atherosclerosis, and it also elevated the risk of, in both terms, the increment of prevalence (OR=1.31, P<0.05) and the quantity of carotid plaques (OR=1.28, P<0.05). When age was also taken into consideration, the largest association, in both terms of prevalence (OR=3.46, P<0.01) and the number of carotid plaques (OR=4.23, P<0.01), was found in subjects over the age of 60 with short sleep duration.

Conclusion

In conclusion, sleep duration less than 5 hours per night is associated with a higher risk of carotid atherosclerosis compared with subjects who sleeps for 5 or over 5 hours per night, and the association may be modified by age.

Grading effect of abnormal glucose status on arterial stiffness and a new threshold of 2-h post-load glucose based on a Chinese community study

AIMS/INTRODUCTION

To investigate the relationship between various glucose metabolic status and arterial stiffness, and further explore the threshold of blood glucose indices for the risk of arterial stiffness.

MATERIALS AND METHODS

The present cross-sectional study included 4,851 individuals from a Chinese community. Overnight fasting blood glucose and 2-h post-load glucose were sampled. Arterial stiffness was measured as brachial-ankle pulse wave velocity. The association was examined using generalized linear regression models. The threshold effect was explored using two piecewise linear regression models by the smoothing plot.

RESULTS

After adjustment for covariates, isolated impaired fasting glucose, isolated impaired glucose tolerance, combined glucose intolerance and newly diagnosed diabetes mellitus were associated with a greater risk of arterial stiffness compared with normal glucose tolerance (B = 18.09, 95% confidence interval [CI] 0.42-35.76, P = 0.045; B = 28.51, 95% CI: 3.40-53.62, P = 0.026; B = 60.70, 95% CI: 38.37-83.04, P < 0.001; B = 95.06, 95% CI: 71.88-118.25, P < 0.001, respectively). Furthermore, there was a non-linear relationship between 2-h post-load glucose and arterial stiffness. A threshold for 2-h post-load glucose of 6.14 mmol/L was observed for the risk of arterial stiffness.

CONCLUSIONS

Impaired fasting glucose, impaired glucose tolerance, combined glucose intolerance and newly diagnosed diabetes mellitus were related to a greater risk of arterial stiffness compared with normal glucose levels. A threshold for 2-h post-load glucose of 6.14 mmol/L probably exists for the risk of arterial stiffness.

Associations of plasma homocysteine levels with peripheral systolic blood pressure and noninvasive central systolic blood pressure in a community-based Chinese population

Previous studies indicated that homocysteine (Hcy) is associated with higher peripheral systolic blood pressure (pSBP). There have been few data on the relationship between Hcy and central SBP (cSBP). A total of 4,364 Chinese subjects from the Shijingshan community in Beijing were included. cSBP and pSBP were measured with an Omron HEM-9000AI device. Subjects were 57.20 ± 8.9 years old, 37.9% were male. The median of Hcy was 11.96 μmol/L. The mean of cSBP and pSBP was 129.94 ± 18.03 mmHg and 133.25 ± 18.58 mmHg. lnHcy was associated with cSBP (adjusted β = 2.17, SE = 0.80, P = 0.007) and pSBP (adjusted β = 2.42, SE = 0.75, P = 0.001). With increasing Hcy, there were enhanced correlations of Hcy with pSBP and cSBP (p for trend between quartiles <0.01). Using Q1 for reference, the Q4 was associated with cSBP (adjusted β = 1.77, SE = 0.89, P = 0.047) and pSBP (adjusted β = 2.15, SE = 0.84, P = 0.011). The correlations were more significant in non-obese subjects than in obese subjects (cSBP: β = 4.30 vs 0.46, pSBP: β = 5.04 vs 1.18, P for interaction <0.001). Our study showed that Hcy was associated with higher cSBP and pSBP, especially in non-obese subjects.

White blood cell count predicts the odds of kidney function decline in a Chinese community-based population

Background

Inflammatory processes are very important in the development of kidney disease. Nevertheless, the association between white blood cell (WBC) count and the risk of renal dysfunction has not been well-established, especially in subjects without chronic kidney disease (CKD). Our study investigated the association between WBC count and kidney function decline in a Chinese community-based population with baseline estimated glomerular filtration rate (eGFR) ≥60 mL/min/1.73 m².

Methods

A total of 3768 subjects who were enrolled in an atherosclerosis cohort in Beijing were included in this study. EGFRs were calculated at baseline and follow-up using the CKD-EPI formula. The outcomes of this study were renal function decline (RFD) (a drop in eGFR stage along with a decline in eGFR of 25% or exceeding 5 mL/min/1.73 m²/year), rapid eGFR decline (an annual decrease in eGFR exceeding 3 mL/min/1.73 m²), and incident CKD (eGFR <60 min/1.73 m² at follow-up). Multivariate logistic regression models were used to evaluate the associations between WBC count and each outcome.

Results

On average, the subjects were 56.6 ± 8.5 years old, and 35.9% were male. Of the participants, 48.6% had hypertension and 17.4% had diabetes. The mean (SD) WBC count at baseline was 6.1 ± 1.5 × 10⁹/L. The mean (SD) eGFR at baseline was 101.1 ± 10.6 mL/min/1.73 m². After 2.3 years follow-up, the incidence rates of RFD, rapid eGFR decline and new CKD were 7.7, 20.9, and 0.8%, respectively. WBC count was significantly related to RFD, rapid eGFR decline and new CKD in the univariate analyses. Even after adjustment for demographic variables, comorbidities, medications and baseline eGFR, these associations remained. Moreover, similar trends in RFD were observed in nearly all subgroups stratified by each confounding variable. The increase in the odds of RFD associated with each 10⁹/L increase in WBC count was significantly greater in subjects not undergoing treatment with lipid-lowering drugs than those not undergoing this treatment (P-interaction: 0.05).

Conclusions

In conclusion, elevated WBC count served as a predictor of the odds of kidney function decline in this population, which supports the hypothesis that systemic inflammation may serve as a risk factor for CKD development.

Electronic supplementary material

The online version of this article (doi:10.1186/s12882-017-0608-4) contains supplementary material, which is available to authorized users.

WBC count predicts the risk of new-onset peripheral arterial disease in a Chinese community-based population

This longitudinal cohort study investigated whether peripheral WBC counts could predict peripheral arterial disease (PAD) incidence after a 2.3-year follow-up in a Chinese community-based population without PAD at baseline. A total of 3555 Chinese subjects without fever and PAD at baseline from an atherosclerosis cohort were included in our analysis. The ankle brachial index (ABI) was measured, and PAD was defined as an ABI <0.9. Multivariate regression models were used to evaluate the association of WBC count and new-onset PAD. The mean (±s.d.) baseline WBC count was 6.11±1.54 × 10⁹ l^-1, the mean (±s.d.) ABI was 1.11±0.08 at baseline and the incidence of PAD was 2.7% over 2.3 years. WBC counts were significantly associated with PAD incidence (odds ratio (OR)=1.27, 95% confidence interval (CI): 1.14-1.41, P<0.0001) with every 1 × 10⁹ l^-1 increase in WBC count. This relationship remained significant (OR=1.21, 95% CI: 1.08-1.36, P=0.0014) even after adjusting for other variables. The highest WBC quartile group had increased risk when compared with the lowest quartile group (OR=2.14, 95% CI: 1.09-4.22, P=0.027) in a multivariate logistic model. Furthermore, we did not find significant heterogeneity among the analyzed subgroups based on sex (male or female), age (<60 or ⩾60 years old), body mass index (BMI, <25 or ⩾25 kg m^-2), current smoking, current drinking, hypertension, diabetes mellitus, dyslipidemia or cardiovascular disease. In conclusion, elevated WBC counts independently predict the risk of new-onset PAD in a Chinese community-based population, supporting the hypothesis that systemic inflammation plays an important role in PAD development.

Relationship between plasma homocysteine level and lipid profiles in a community-based Chinese population

Background

Previous studies established a possible link among hyperhomocysteinemia (HHcy), dyslipidemia, and atherosclerosis. However, there was limited epidemic data concerning the relation between HHcy and lipid profiles, especially in community-based Chinese populations. This study aim to investigate the association of plasma homocysteine (Hcy) level with lipid profiles in a Chinese community-based population without lipid-lowering treatment.

Method

A total of 4660 Chinese subjects from a cohort of the Shijingshan district in Beijing were included in the analysis. Plasma total Hcy, serum lipid files including total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C) as well as relevant metabolic risk factors were measured. Multivariate regression models adjusting for age, gender, smoking, drinking, physical activity, vitamin B supplement, body mass index, fasting blood glucose level, serum creatinine, systolic and diastolic blood pressure were used to evaluate associations of Hcy and lipid profiles.

Result

Subjects were 56.75 ± 8.91 years old, and 38.15% were male. Median (IQR) Hcy was 11.98 (10.00–14.93) μmol/L, and 24.4% had HHcy (defined as Hcy ≥ 15 μmol/L). Mean (SD) baseline TC was 5.34 ± 0.98 mmol/L, LDL-C was 3.27 ± 0.81 mmol/L, and HDL-C was 1.43 ± 0.38 mmol/L. Median (IQR) of TG was 1.28 (0.91–1.85) mmol/L. In multivariable linear-regression analyses, lnHcy (ln transformation for Hcy) level was positively associated with lnTG (adjusted β = 0.075, SE = 0.021, P = 0.001). Using Hcy < 15 μmol/L as a reference, HHcy was independently associated with both lnTG (adjusted β = 0.056, SE = 0.020, P = 0.004) and lnHDL (adjusted β = −0.018, SE = 0.009, P = 0.038). In multivariable logistic-regression analyses, HHcy was associated with increasing risk of low HDL-C (HDL-C < 1.04 mmol/L; adjusted odds ratio [OR] =1.406, 95% confidence interval [CI]: 1.143 – 1.728, P = 0.001) and hypertriglyceridemia (TG ≥ 1.7 mmol/L; adjusted OR = 1.293, 95% CI: 1.096–1.524, P = 0.002) after adjusting the confounders. However, there were no significant associations between Hcy and TC or LDL-C.

Conclusion

The present study showed that HHcy was independently associated with hypertriglyceridemia and low levels of HDL-C, which provides evidence that Hcy levels might affect HDL-C and TG metabolism.