Clinical application and potential effects of 2014 hypertension guidelines on incident cardiovascular events

Metformin use and cardiovascular outcomes in patients with diabetes and chronic kidney disease: a nationwide cohort study

BACKGROUND

Metformin has recently been shown not to increase the risk of lactic acidosis in patients with chronic kidney disease (CKD). Thus, the criteria for metformin use in this population has expanded. However, the relationship between metformin use and clinical outcomes in CKD remains controversial.

METHODS

This study considered data from 97,713 diabetes patients with an estimated glomerular filtration rate of <60 mL/min/1.73 m2. The primary outcome was major adverse cardiac and cerebrovascular events (MACCE), and the secondary outcomes were all-cause mortality and incident end-stage renal disease (ESRD).

RESULTS

Metformin users had a significantly higher risk of MACCE than non-users (hazard ratio [HR], 1.20; 95% confidence interval [CI], 1.14-1.26; p < 0.001). However, metformin users had a lower risk of all-cause mortality (HR, 0.78; 95% CI, 0.74-0.81; p < 0.001) and ESRD (HR, 0.44; 95% CI, 0.42-0.47; p < 0.001) during follow-up than non-users did. The relationships between metformin use and clinical outcomes remained consistent in propensity score matching analyses and subgroup analyses of patients with adequate adherence to anti-diabetes medication.

CONCLUSION

Treatment with metformin was associated with an increased risk of MACCE in patients with diabetes and CKD. However, metformin users had a lower risk of all-cause mortality and ESRD during follow-up than non-users did. Therefore, metformin needs to be carefully used in patients with CKD.

Sex differences in the blood pressure level associated with increased risks of cardiovascular events: a Korean nationwide population-based cohort study

Hypertension is a leading risk factor for cardiovascular events and death. Despite differences in clinical implications of hypertension between men and women, guidelines establishing optimal blood pressure (BP) targets are still debated. The aim of this study was to investigate sex differences in the BP level associated with increased risks of major adverse cardiac and cerebral events (MACCEs) among antihypertensive-treated patients. Using data from the Korean National Health Insurance Service-National Sample Cohort, we enrolled antihypertensive-treated patients and divided them into four categories: Group 1: SBP < 120 and DBP < 80 mm Hg; Group 2: 120 ≤ SBP < 130 and DBP < 80 mm Hg; Group 3: 130 ≤ SBP < 140 or 80 ≤ DBP < 90 mm Hg; and Group 4: SBP ≥ 140 or DBP ≥ 90 mm Hg. We performed time-dependent cox regression analysis to investigate sex differences in the BP levels that increased the risk of MACCEs. Most of the 98 267 patients fell into Group 3 (53.2% men and 52.8% women) and Group 4 (30.5% men and 28.1% women). During 8.34 ± 2.07 years, there were 8,813 MACCEs and 791 deaths. The incidences of MACCEs and death tended to increase as the BP increased in both sexes. Compared to Group 1, the risk of MACCEs significantly increased only in Group 4 for men, while it significantly increased in Groups 3 and 4 for women. This study shows that there are sex differences in the BP level at which the risk of MACCEs increases. Our finding suggests that sex should be significantly considered when determining the optimal BP target in patients undergoing hypertension treatment.

The protective effect of klotho against contrast-associated acute kidney injury via the antioxidative effect

As oxidative stress is one major factor behind contrast-associated acute kidney injury (CA-AKI), we investigated the protective effect of klotho against CA-AKI via the antioxidative effect. In in vitro experiments, cells (NRK-52E) were divided into the following three groups: control, iopamidol, or iopamidol + recombinant klotho (rKL) groups. Moreover, cell viability was measured with the Cell Counting Kit-8 assay, and oxidative stress was examined with 2',7'-dichlorodihydrofluorescein diacetate fluorescence intensity. RT-PCR and Western blot analysis were performed to assess propidium iodide klotho expression, and Bax-to-Bcl-2 and apoptosis ratios were evaluated with annexin V/Hoechst 33342 staining. Furthermore, we knocked down the klotho gene using siRNA to verify the endogenous effect of klotho. In our in vivo experiments, oxidative stress was evaluated with the thiobarbituric acid-reactive substance assay, and apoptosis was evaluated with the Bax-to-Bcl-2 ratio and cleaved caspase-3 immunohistochemistry. Additionally, cell and tissue morphology were investigated with transmission electron microscopy. In both in vitro and in vivo experiments, mRNA and protein expression of klotho significantly decreased in CA-AKI mice compared with control mice, whereas oxidative stress and apoptosis markers were significantly increased in CA-AKI mice. However, rKL supplementation mitigated the elevated apoptotic markers and oxidative stress in the CA-AKI mouse model and improved cell viability. In contrast, oxidative stress and apoptotic markers were more aggravated when the klotho gene was knocked down. Moreover, we found more cytoplasmic vacuoles in the CA-AKI mouse model using transmission electron microscopy but fewer cytoplasmic vacuoles in rKL-supplemented cells. The present study shows that klotho in proximal tubular cells can protect against CA-AKI via an antioxidative effect.

Association of blood pressure components with mortality and cardiovascular events in prehypertensive individuals: a nationwide population-based cohort study

BACKGROUND

The effects of each blood pressure index [systolic and diastolic blood pressure (SBP, DBP), pulse pressure (PP), mean arterial pressure (MAP)] on the occurrence of mortality and cardiovascular (CV) events have not yet been investigated in prehypertensive populations.

METHODS

A total of 30,258 prehypertensive Korean participants underwent periodic health examination between 2003 and 2004 were enrolled, and the associations of BP components with mortality and CV events were investigated. Moreover, based on the DBP [80 ≤ DBP <90 mmHg (N = 21,323) and DBP <80 mmHg (N = 8,935)], the effects of BP components were also evaluated.

RESULTS

Multivariate Cox analyses in prehypertensive group revealed that the hazard ratios (HRs) were 1.121 and 1.130 per 10 mmHg increase in SBP and PP for mortality, respectively. Additionally, 10 mmHg increase of SBP (HR:1.090) was still significantly, but increase of PP (HR:1.060) was marginally associated with higher incidence of CV events. However, there were no significant associations with increase in DBP or MAP on adverse clinical outcomes in prehypertensive group. In the prehypertensive subjects with DBP <80 mmHg, CV events more frequently occurred by 38.8% and 28.5% per 10 mmHg increase in SBP and PP, respectively.

CONCLUSIONS

Prehypertensive subjects might need to be cautioned when they have high SBP or PP with low DBP even in healthy populations. Key message Prehypertensive subjects should be cautioned when they have high-systolic blood pressure or pulse pressure with low-diastolic blood pressure, even without previous hypertension, diabetes mellitus or chronic kidney disease.

Level of Blood Pressure Control and Cardiovascular Events: SPRINT Criteria Versus the 2014 Hypertension Recommendations

BACKGROUND

Blood pressure (BP) targets from the SPRINT (Systolic Blood Pressure Intervention Trial) differ from targets of the 2014 hypertension (HTN) recommendations of the Eighth Joint National Committee.

OBJECTIVES

The goal of this study was to estimate the proportion of hypertensive adults with who would meet BP goals under the SPRINT criteria and under the 2014 recommendations, and to determine related effects on cardiovascular morbidity and mortality.

METHODS

We used data from the Korean National Health and Nutrition Examination Survey of 2008 to 2013 (n = 13,346), as well as the Korean National Health Insurance Service health examinee cohort of 2007 (n = 67,965), to estimate the proportion of subjects meeting BP goals of each of the criteria. Using data from the Korean National Health Insurance Service health examinee cohort of 2007 (n = 67,965), we compared risks of major cardiovascular events (composite of nonfatal myocardial infarction, nonfatal stroke, or death from cardiovascular causes) associated with different BP control goals.

RESULTS

A substantially lower proportion of hypertensive adults met BP goals of the SPRINT criteria compared with the 2014 recommendations (11.9% vs. 70.8%, respectively). Ten-year predicted cardiovascular risks were lowest in the intensive control group (below SPRINT BP goals), intermediate in the less-intensive group (above SPRINT goals but below 2014 recommendation goals), and highest in the uncontrolled group (above 2014 recommendations) (6.15%, 7.65%, and 9.39%, respectively; p < 0.001). After multivariable adjustment, the less-intensive and uncontrolled groups had a greater risk of major cardiovascular events (hazard ratios 1.17 and 1.62, respectively; p value for trend, <0.001) than the intensive group.

CONCLUSIONS

Substantially fewer hypertensive adults would meet SPRINT BP goals than would meet 2014 recommendation goals. Stricter BP control is associated with a decreased risk of major cardiovascular events.

Blood Pressure Control During Chronic Kidney Disease Progression

BACKGROUND

Hypertension is a major cause of end-stage renal disease, and blood pressure (BP) control is crucial in patients with chronic kidney disease (CKD). However, it is generally inadequately controlled in CKD patients. We investigated the prevalence of CKD patients with inadequate BP control and its related factors, based on the CKD stage.

METHODS

We analyzed the health examination sample cohort database, which consisted of the randomly selected participants among all the citizens who received the health examination provided by National Health Insurance Service of Korea in 2012 and 2013.

RESULTS

There were 27,350 CKD patients (7.9%) out of a total of 345,044 participants. As CKD stage progressed, there were more patients with poorly controlled hypertension compared to those with well-controlled hypertension. In addition, systolic BP increased with CKD stage progression, while diastolic BP was not significantly different. Age, female, body mass index, increased pulse pressure, CKD stage, and levels of fasting glucose, total cholesterol, hemoglobin, and proteinuria were significant factors associated with poor control of BP in hypertensive CKD patients.

CONCLUSION

The proportion of CKD patients with poorly controlled hypertension significantly increased as CKD progressed, mainly associated with the increase in pulse pressure. However, future investigation for causal relationship between poorly controlled hypertension and its related factors is needed.

Antihypertensive drug prescription patterns and their impact on outcome of blood pressure in Ethiopia: a hospital-based cross-sectional study

Background

Irrational prescription is strongly associated with poor control of hypertension. The present study aimed to evaluate antihypertensive drug prescription trends and to measure their impact on the level of blood pressure (BP) control in Gondar University Hospital, Gondar, Ethiopia.

Methods

A hospital-based retrospective cross-sectional study was conducted from May 30 to June 30, 2016. All hypertensive patients on medication were included. A structured data abstraction form was prepared to gather the necessary information. The prescription patterns and BP level were measured retrospectively. A binary logistic regression was computed to determine the effect of different prescription patterns on BP control.

Results

A total of 596 hypertension patients were recruited for the study; of them, 561(94%) met the study criteria. The mean age of the respondents was 55.96±14.6 years. Females constituted 58.2% of the study population. Approximately fifty percent of the prescriptions were monotherapies. Twice-daily dosing was associated with lower risk of uncontrolled hypertension (crude odds ratio [COR] =0.51[0.15–0.73], adjusted odds ratio [AOR] =0.69[0.163–0.91]). Monthly appointment was linked with a nearly 90% reduced incidence of uncontrolled BP (COR =0.15[0.04–0.73], AOR =0.093[0.024–0.359]).

Conclusion

Monotherapies were the most frequently prescribed regimens. Twice-daily dosing and monthly appointments were associated with low incidence of uncontrolled BP. Clinicians should be vigilant in adjusting the frequency of dosing and should fix appointment date in consultation with their patients.