Proteinuria and risk of stroke in patients with hypertension: The Kailuan cohort study

Changes in urine dipstick proteinuria and its relation to the risk of diabetic retinopathy and neuropathy

BACKGROUND

Proteinuria is considered as a predictor for cardiovascular complications in diabetes mellitus (DM). However, no study has examined the association between changes in proteinuria and the risk of diabetic microvascular complications.

METHODS

Study participants were 71,825 DM patients who received urine dipstick test for proteinuria both in 2003-2004 and 2006-2007. They were categorized into four groups according to changes in proteinuria over 3 years (negative: negative → negative, resolved: proteinuria ≥ 1+ → negative, incident: negative → proteinuria ≥ 1+, persistent: proteinuria ≥ 1+ → proteinuria ≥ 1+). Cox-proportional hazard model was used in assessing the adjusted hazard ratios (HR) and 95% confidence interval (CI) for incidence of retinopathy, and neuropathy (adjusted HR [95% CI]).

RESULT

In all of DM patients, risk for comprehensive incidence of retinopathy and neuropathy increased in all types of proteinuria changes. In type 1 DM, HR for retinopathy and neuropathy generally increased in order of negative (reference), resolved (2.175 [1.150-4.114] and 1.335 [0.909-1.961]), incident (2.088 [1.185-3.680] and 1.753 [1.275-2.409]), and persistent proteinuria (1.314 [0.418-4.134] and 2.098 [1.274-3.455]). This pattern of relationship was similarly observed in type 2 DM for retinopathy and neuropathy: negative (reference), resolved (1.490 [1.082-2.051] and 1.164 [0.988-1.371]), incident (1.570 [1.161-2.123] and 1.291 [1.112-1.500]), and persistent proteinuria (2.309 [1.407-3.788] and 1.272 [0.945-1.712]).

CONCLUSION

Risk for diabetic retinopathy and neuropathy generally increased in order of negative, resolved, incident, and persistent proteinuria. Once manifested proteinuria was associated with the increased risk of diabetic retinopathy and neuropathy even after remission of proteinuria.

Persistent proteinuria is associated with the occurrence of cardiovascular disease: a nationwide population-based cohort study

Proteinuria is an important risk factor for cardiovascular disease (CVD) and acts as a surrogate marker of renal damage. This study aimed to determine the association between changes in proteinuria and the occurrence of CVD. In our study, 1,708,712 participants who consecutively underwent national health examinations from 2003-2004 (first period) to 2005-2006 (second period) were included. They were classified into four groups based on the presence of proteinuria at the two consecutive health examinations: (1) normal (0 → 0), (2) proteinuria-improved (participants who had improved proteinuria (+ 1 → 0, + 2 → ≤ +1 [0 or + 1], ≥ +3 → ≤ +2 [0, + 1 or + 2]), (3) proteinuria-progressed (0 → ≥ +1, + 1 → ≥ +2, + 2 → ≥ +3), and (4) proteinuria-persistent (+ 1 → +1, + 2 → +2, ≥ +3 → ≥ +3). We used a multivariate Cox proportional hazards model to assess the occurrence of CVD according to changes of presence and severity of proteinuria. During a median of 14.2 years of follow-up, 143,041 participants (event rate, 8.37%) with composite CVD were observed. Compared with the normal group, the risk of incident risk of CVD was increased according to the severity of proteinuria in each of the persistent, progressed, and improved groups (p for trend < 0.001). In a pairwise comparison, the risk of composite CVD in the improved (hazard ratio [HR]: 1.32, 95% confidence interval [CI]: 1.27-1.37), progressed (HR: 1.49, 95% CI: 1.44-1.54), and persistent groups (HR: 1.78, 95% CI: 1.64-1.94) were higher than that of the normal group. Furthermore, the improved group had a relatively lower risk of composite CVD compared to the persistent group (HR: 0.75, 95% CI: 0.69-0.83, p < 0.001). The incidence risk of composite CVD was associated with changes of presence and severity of proteinuria. Persistent proteinuria may be associated with increased risk of CVD, even compared with improved or progressed proteinuria status.

The association between changes in proteinuria and the risk of cerebral infarction in the Korean population

BACKGROUND

Proteinuria is a risk factor for cerebral infarction. It is known that proteinuria can change over time. However, published data is scarce for the association between changes in proteinuria and the risk of cerebral infarction.

METHOD

Study participants were 276,861 Koreans who were assessed for urine dipstick proteinuria both in 2003-2004 and 2007-2008. They were categorized into four groups by changes in proteinuria over 4 years (negative: negative → negative, resolved: proteinuria ≥ 1+ → negative, incident: negative → proteinuria ≥ 1+, persistent: proteinuria ≥ 1+ → proteinuria ≥ 1 + ). We used multivariate adjusted Cox-proportional hazard model in calculating the adjusted hazard ratios (HR) and 95% confidence interval (CI) for cerebral infarction until 2013 according to changes in proteinuria.

RESULT

Adjusted HR and 95% CI for cerebral infarction significantly increased in order of persistent, incident, and resolved proteinuria, compared with negative proteinuria (negative: reference, resolved: 1.166 [1.009-1.347], incident: 1.345 [1.188-1.522], and persistent: 1.443 [1.089-1.912]). In gender subgroup analysis, men showed the more clear association between changes in proteinuria and the risk of cerebral infarction (negative: reference, resolved: 1.284 [1.057-1.560], incident: 1.351 [1.149-1.589], and persistent: 1.428 [1.014-2.012]).

CONCLUSION

All types of proteinuria changes were associated with the increased risk of cerebral infarction, even in participants with once manifested but vanishing proteinuria.

Increased Stroke Risk in Metabolically Abnormal Normal Weight: a 10-Year Follow-up of 102,037 Participants in China

The purpose of this study was to investigate the risks of stroke in subjects with metabolically abnormal normal weight (MANW) in China. We recruited 102,037 participants from the Zhejiang Metabolic Syndrome Cohort and the Kailuan cohort. The mean years of follow-up were 9.9 years. General obesity was defined by body mass index (BMI) ≥ 28, overweight by BMI < 28 and ≥ 24, and normal weight by BMI < 24 and ≥ 18.5. Metabolic abnormality was defined as two or more abnormal components (elevated triglycerides, low high-density lipoprotein cholesterol, elevated systolic blood pressure or diastolic blood pressure, or use of antihypertensive drug therapy, elevated fasting plasma glucose, or antidiabetic treatment). A multiple Cox regression model was used to calculate hazard ratio (HR) and its 95% confidence interval (CI), adjusted by potential confounding factors. Overall HR of the risks in two cohorts was calculated by a meta-analysis. Compared with the subjects who were metabolically normal with normal weight (MNNW), the pooled HR for stroke in MANW subjects was 1.82 (95% CI, 1.59-2.07). The risks of stroke in MANW subjects were significantly lower than that in subjects with metabolically abnormal obesity (MAO), but higher than that in those with metabolically normal obesity (MNO) (P < 0.05). These associations remained in the subtypes of cerebral infarction and cerebral hemorrhage. In normal-weight subjects, the HR for stroke was significantly positively correlated with the number of abnormal metabolic components (P_trend < 0.001). In brief, metabolic abnormality increased the risk of stroke irrespective of obesity status. MANW individuals showed a greater risk of stroke, and this risk was positively correlated with the number of abnormal metabolic components.

From protein uptake to Dent disease: An overview of the CLCN5 gene

Proteinuria is a well-known risk factor, not only for renal disorders, but also for several other problems such as cardiovascular diseases and overall mortality. In the kidney, the chloride channel Cl^-/H⁺ exchanger ClC-5 encoded by the CLCN5 gene is actively involved in preventing protein loss. This action becomes evident in patients suffering from the rare proximal tubulopathy Dent disease because they carry a defective ClC-5 due to CLCN5 mutations. In fact, proteinuria is the distinctive clinical sign of Dent disease, and mainly involves the loss of low-molecular-weight proteins. The identification of CLCN5 disease-causing mutations has greatly improved our understanding of ClC-5 function and of the ClC-5-related physiological processes in the kidney. This review outlines current knowledge regarding the CLCN5 gene and its protein product, providing an update on ClC-5 function in tubular and glomerular cells, and focusing on its relationship with proteinuria and Dent disease.

Is functional disability a risk equivalent to the comorbidity of multi-vascular risk factors for cardiovascular events and all-cause death? A 5-year follow-up study

Background/objectives: Functional disability (FD) is common after stroke and associated with the occurrence of future adverse events; however, whether FD is as strong a risk factor as comorbid vascular risk factors for cardiovascular events and death is unclear. Methods: Consecutive patients 3-6 months after index ischemic stroke were assessed at baseline and followed up for documented new cardiovascular events (recurrent stroke, acute myocardial infarction, and sudden death) and death within 5 years. Comorbidity of vascular risk factors was stratified as low or intermediate-to-high risk according to the Stroke Prognostic Instrument II. Four mutually exclusive cohorts were identified (1) intermediate-to-high risk only, n = 505, (2) FD only, n = 78, (3) both intermediate-to-high risk and FD, n = 264, and (4) low risk and no FD, n = 240. Results: The incidence of cardiovascular events was lowest in patients free of FD with low risk, followed by patients with FD alone, intermediate-to-high risk alone, and both. Compared with intermediate-to-high risk only, patients free of FD with low risk had a significantly lower adjusted hazard ratio (HR) (HR: 0.56, 95% confidence interval [CI]: 0.33-0.94), patients with FD only had a similar HR (HR: 0.47, 95% CI: 0.19 -1.18), and patients with both FD and intermediate-to-high risk had a significantly higher HR (HR: 2.13, 95% CI: 1.53-2.98) of cardiovascular events. A similar trend but a larger HR was noted for all-cause death. Conclusion: FD 3-6 months after ischemic stroke is a risk equivalent to comorbidity of conventional vascular risk factors for the incidence of cardiovascular events and mortality of all-cause death.

Visit-to-Visit Variability of Lipids Measurements and the Risk of Stroke and Stroke Types: A Prospective Cohort Study

BACKGROUND AND PURPOSE

Previous studies suggested increased visit-to-visit variability of total cholesterol (TC) is associated with stroke. This study aimed to investigate the associations of various lipids measurements variability and the risk of stroke and stroke type (ischemic and hemorrhagic stroke).

METHODS

Fifty-one thousand six hundred twenty participants in the Kailuan Study without history of myocardial infarction, stroke, and cancer who underwent three health examinations during 2006 to 2010 were followed for incident stroke. Variability in TC, triglycerides, high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) measurements were measured using the coefficient of variation (CV), standard deviation (SD), variability independent of the mean (VIM), and average real variability (ARV).

RESULTS

During a median of 6.04 years of follow-up, 1,189 incident stroke (1,036 ischemic and 160 hemorrhagic stroke) occurred. In the multivariable-adjusted model, the hazard ratio (HR) comparing participants in the highest versus lowest quartile of CV of HDL-C were 1.21 (95% confidence interval [CI], 1.02 to 1.45; P for trend=0.013) for ischemic stroke. The highest quartile of CV of LDL-C was associated with 2.17-fold risk of hemorrhagic stroke (HR, 2.17; 95% CI, 1.25 to 3.75; P for trend=0.002) compared with the lowest quartile. We did not observe any significant association between TC and triglycerides variability with any of stroke. Consistent.

RESULTS

were obtained when calculating variability index using SD, VIM, or ARV.

CONCLUSIONS

These findings suggest the high visit-to-visit HDL-C and LDL-C variability were associated with an increased incidence of ischemic and hemorrhagic stroke, respectively.