Blood pressure and antihypertensive medication profile in a multiethnic Asian population of stable chronic kidney disease patients

Short-term blood pressure variability and outcomes in non-dialysis chronic kidney disease

Background

Blood pressure variability (BPV) is associated with cardiovascular and all-cause mortality, and has been demonstrated in dialysis patients, but has been poorly studied and remains controversial in non-dialysis chronic kidney disease (CKD) patients. We investigated the effect of short-term BPV on prognosis in this population.

Methods

A total of 245 stage 1–4 CKD patients with 24-h ambulatory blood pressure recordings were recruited. BPV was evaluated by standard deviation, coefficient of variation, and variation independent of the mean, respectively. All subjects were followed up to the composite end-point event or until January 15, 2020. Patients were divided into two groups based on 24-h median variation independent of the mean, and demographics, laboratory indicators and echocardiogram results were compared. Logistic regression was used to analyze the risk factors for increased BPV. Multivariate Cox regression and Kaplan-Meier survival analysis were used to explore the relationship between BPV and renal prognosis and major cardiovascular events.

Results

The mean age was 42.07 ± 12.66 years, with 141 males (57.55%). Multivariate Logistic regression analysis showed that high BMI (OR 1.110, P = 0.017), hyperkalemia (OR 2.227, P = 0.040), increased left ventricular end-diastolic diameter (OR 1.103, P = 0.010) and hypertension (OR 2.525, P = 0.002) were independent risk factors for high BPV. Kaplan-Meier survival analysis showed that renal and cardiovascular outcomes were better in the low BPV group than in the high BPV group (P = 0.006; P = 0.002). After adjusting for age, sex and traditional kidney related risk factors, BPV were not independently associated with renal outcomes. High BPV (HR 4.662, P = 0.017) was the main independent risk factor for major cardiovascular events in CKD.

Conclusions

In non-dialysis CKD, short-term BPV was associated with major cardiovascular disease but not renal progression. BMI, hypertension, potassium balance, and left ventricular end-diastolic diameter influenced short-term BPV.

Hypertension and chronic kidney disease in Asian populations

The countries of Asia are home to multiple ethnicities. There are ethnic differences in diet, culture, and attitudes towards health screening, access to care, and treatment of chronic diseases. Chronic kidney disease (CKD) and end-stage kidney disease (ESKD) have rising incidence and prevalence due to increased affliction with non-communicable diseases of diabetes and hypertension. To prevent the expensive complications of ESKD, one of the most important risk factors to control is hypertension in patients with CKD. We performed a narrative review on the prevalence of CKD in patients with hypertension, the prevalence and control of hypertension in patients with CKD, and the dietary sodium intake in CKD populations.

Utilization of antihypertensive drugs among chronic kidney disease patients: Results from the Chinese cohort study of chronic kidney disease (C-STRIDE)

The utilization of antihypertensive drugs plays an important role in blood pressure control among chronic kidney disease (CKD) patients. Limited information was available on how antihypertensive drugs were used among Chinese CKD patients. In the present study, the utilization of antihypertensive drugs among a subgroup of hypertensive participants with a complete record of antihypertensive drug information from the Chinese Cohort Study of Chronic Kidney Disease was analyzed. Among 2213 subjects, 61.7% and 26.5% had their blood pressure controlled to <140/90 mmHg and <130/80 mmHg, respectively. In total, 38.5% were on monotherapy. Of those patients who received combination therapy, 57.8% were treated with a two-drug combination. Renin-angiotensin system inhibitors (RASIs) were the most commonly prescribed drugs (71.2%). Only 10.2% of the patients were prescribed diuretics. After multivariable adjustment, participants taking RASI were more likely to have their blood pressure controlled to <140/90 mmHg (prevalence ratio (PR) 1.153, 95% confidence interval (CI): 1.071-1.240). CKD stage 4 (PR 0.548, 95% CI: 0.434-0.692) was associated with RASIs treatment. Additionally, diabetes (PR 1.498, 95% CI: 1.120-2.004), albumin/creatinine ratio ≥300 mg/g (PR 1.547, 95% CI: 1.020-2.344), and CKD stage 4 (PR 2.022, 95% CI: 1.223-3.343) were associated with diuretic use. The results suggested that combination therapy, diuretics use in general, and utilization of RASIs in advanced CKD stage were insufficient in the current treatment of Chinese hypertensive CKD patients.

Evaluation of different bioimpedance methods for assessing body composition in Asian non-dialysis chronic kidney disease patients

Background

Chronic kidney disease (CKD) is associated with fluid retention, which increases total body water (TBW) and leads to changes in intracellular water (ICW) and extracellular water (ECW). This complicates accurate assessments of body composition. Analysis of bioelectrical impedance may improve the accuracy of evaluation in CKD patients and multiple machines and technologies are available. We compared body composition by bioimpedance spectroscopy (BIS) against multi-frequency bioimpedance analysis (BIA) in a multi-ethnic Asian population of stable, non-dialysis CKD patients.

Methods

We recruited 98 stable CKD patients comprising 54.1% men and 70.4% Chinese, 9.2% Malay, 13.3% Indian, and 8.2% other ethnicities. Stability was defined as no variation in serum creatinine > 20% over three months. Patients underwent BIS analyses using a Fresenius body composition monitor, while BIA analyses employed a Bodystat Quadscan 4000.

Results

Mean TBW values by BIS and BIA were 33.6 ± 7.2 L and 38.3 ± 7.4 L; mean ECW values were 15.8 ± 3.2 L and 16.9 ± 2.7 L; and mean ICW values were 17.9 ± 4.3 L and 21.0 ± 4.9 L, respectively. Mean differences for TBW were 4.6 ± 1.9 L (P < 0.001), for ECW they were 1.2 ± 0.5 L (P < 0.001), and for ICW they were 3.2 ±1.8 L (P < 0.001). BIA and BIS measurements were highly correlated: TBW r = 0.970, ECW r = 0.994, and ICW r = 0.926. Compared with BIA, BIS assessments of fluid overload appeared to be more associated with biochemical and clinical indicators.

Conclusion

Although both BIA and BIS can be used for body water assessment, clinicians should be aware of biases that exist between bioimpedance techniques. The values of body water assessments in our study were higher in BIA than in BIS. Ethnicity, sex, body mass index, and estimated glomerular filtration rate were associated with these biases.

Hypertension and blood pressure variability management practices among physicians in Singapore

Purpose

There are limited data on blood pressure variability (BPV) in Singapore. The absence of updated local guidelines might contribute to variations in diagnosis, treatment and control of hypertension and BPV between physicians. This study evaluated BPV awareness, hypertension management and associated training needs in physicians from Singapore.

Materials and methods

Physicians from Singapore were surveyed between September 8, 2016, and October 5, 2016. Those included were in public or private practice for ≥3 years, cared directly for patients ≥70% of the time and treated ≥30 patients for hypertension each month. The questionnaire covered 6 main categories: general blood pressure (BP) management, BPV awareness/diagnosis, home BP monitoring (HBPM), ambulatory BP monitoring (ABPM), BPV management and associated training needs.

Results

Responses from 60 physicians (30 general practitioners [GPs], 20 cardiologists, 10 nephrologists) were analyzed (77% male, 85% aged 31–60 years, mean 22 years of practice). Approximately 63% of physicians considered white-coat hypertension as part of BPV. The most common diagnostic tool was HBPM (overall 77%, GPs 63%, cardiologists 65%, nephrologists 70%), but ABPM was rated as the tool most valued by physicians (80% overall), especially specialists (97%). Withdrawn Singapore guidelines were still being used by 73% of GPs. Approximately 48% of physicians surveyed did not adhere to the BP cutoff recommended by most guidelines for diagnosing hypertension using HBPM (>135/85 mmHg). Hypertension treatment practices also varied from available guideline recommendations, although physicians did tend to use a lower BP target for patients with diabetes or kidney disease. There were a number of challenges to estimating BPV, the most common of which was patient refusal of ABPM/HBPM. The majority of physicians (82%) had no training on BPV, but stated that this would be useful.

Conclusion

There appear to be gaps in knowledge and guideline adherence relating to the assessment and management of BPV among physicians in Singapore.