Association between microalbuminuria and outcome of non-diabetic population aged 40 years and over: The reaction study

Predictive Factors for Target Organ Injuries in Hypertensive Individuals

Background

The causal relationship between systemic arterial hypertension and target organ damage (TOD) is well known, as well as the association with cardiovascular risk factors (CV). Ambulatory blood pressure monitoring (ABPM) is important in monitoring hypertension and assessing the risk of TOD.

Objective

To evaluate the relationship between blood pressure (BP) and clinical and biochemical parameters in the development of TOD in hypertensive patients.

Methods

This was a retrospective cohort study with 162 hypertensive patients followed for an average period of 13 years. The TOD investigated were left ventricular hypertrophy (LVH), microalbuminuria, coronary artery disease (CAD) and stroke. Blood pressure was assessed by ABPM and LVH using echocardiogram and electrocardiogram, respectively. Biochemical-metabolic tests and 24-hour microalbuminuria were performed at baseline and follow-up. The P-value <0.05 was considered significant.

Results

The average age was 69±11.8 years, with a predominance of women (64.8%), white ethnicity (79.6%) and diabetics (78.4%). ABPM showed a significant reduction in BP values during follow-up, although without association with TOD (microalbuminuria, stroke, and CAD), except for LVH that showed a correlation with sleep BP ≥120/70 mmHg (P=0.044). The most frequent TODs were LVH (29.6%), microalbuminuria (26.5%), CAD (19.8%) and stroke (17.3%). In the follow-up, there was an association between LVH and diabetes; microalbuminuria was associated with diabetes and triglycerides; stroke was associated with HDL-cholesterol (HDL-c), microalbuminuria and carotid disease. CAD showed a relationship with age and HDL-c.

Conclusion

Predictive factors for TOD are age, microalbuminuria, diabetes, HDL-c, triglycerides and carotid disease. Nocturnal BP is correlated with LVH. The absence of a relationship between ABPM and other TODs can be explained by the use of effective drugs, improvement of metabolic and blood pressure parameters.

The Risk Threshold for Hemoglobin A1c Associated With Albuminuria: A Population-Based Study in China

BACKGROUND

Diabetic kidney disease (DKD) is a kind of common microvascular complication of diabetes. This study aims to explore the possible links between blood sugar level and albuminuria, providing the exact cut point of the "risk threshold" for blood glucose with DKD.

METHODS

The relationship between blood glucose and albuminuria was modeled using linear and logistic regression in the REACTION study cohorts (N= 8932). Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated by logistic regression model. Two-slope linear regression was used to simulate associations between blood glucose and ACR.

RESULTS

We found that the increase in ACR was accompanied by increased HbA1c, with a turning point at 5.5%. The positive correlation remained highly significant (P<0.001) when adjusted for age, sex, marital status, education, smoking status, drinking status, BMI, waistline, SBP and DBP. In subgroup analyses including gender, obesity, hypertension, and smoking habits, the relationship was significant and stable.

CONCLUSIONS

We determined a risk threshold for HbA1c associated with albuminuria in a Chinese population over the age of 40. HbA1c ≥ 5.5% was positively and independently associated with ACR. These results suggest the necessity of early blood glucose control and renal function screening for DKD in at-risk populations.