Non-pharmacological aspects of blood pressure management: what are the data? Kidney Int. 2011;79:1061-1070. [PMID: 21389976 DOI: 10.1038/ki.2011.46]

Positive correlation between body weight and body mass index with blood pressure in young adults

Study assessing the correlation between body weight and body mass index (BMI) with blood pressure in young adults is still limited. The aim of this was to investigate the link between body weight and BMI with blood pressure, as well as to assess how much increasing of body weight and BMI contribute to raising blood pressure in young men and women. A cross-sectional study was conducted among 1,107 healthy young adults aged 18-22 years (women, n=705; men, n=402). Chi-squared test was used to assess the association between body weight and BMI with blood pressure. The Pearson correlation and linear regression analysis were used to determine the correlation and direction of the relationship between body weight and BMI with blood pressure. Our data indicated the associations between body weight and BMI with blood pressure (both had p=0.001). There was a strong correlation between body weight and systolic blood pressure (SBP) (r=0.709; p<0.001), whereas the correlation between body weight and diastolic blood pressure (DBP) was moderate (r=0.374; p<0.001). BMI moderately influenced SBP and DBP (r=0.488 and r=0.358; p<0.001). A linear correlation analysis revealed a positive correlation between body weight and BMI with blood pressure, where an increase in body weight of 1 kg resulted an increase in SBP of 0.725 mmHg and DBP of 0.318 mmHg. In addition, an increase in BMI of 1 kg/m2 followed by an increase in SBP and DBP of 1.6 mmHg and 0.834 mmHg, respectively. This study highlights that nutritional status in young men and women is linked and has a positive correlation with blood pressure.

Higher Nocturnal Blood Pressure and Blunted Nocturnal Dipping Are Associated With Decreased Daytime Urinary Sodium and Potassium Excretion in Patients With CKD

Introduction

Sodium homeostasis is intimately associated with blood pressure (BP) rhythm, and potassium excretion is closely associated with sodium excretion in the general population. However, the association between circadian sodium and potassium pattern excretion and nocturnal BP in patients with chronic kidney disease (CKD) is not elucidated.

Methods

We evaluated the correlation between the day-to-night ratio of urinary sodium and potassium excretion rate, nocturnal blood pressure, and nocturnal BP dipping in a CKD cohort.

Results

A total of 3152 (56.76% males, mean age 47.63 years) individuals with CKD were included in the study. Patients in quartile 1 (with the lowest ratio) exhibited a 12 mmHg or 9 mmHg higher nocturnal systolic blood pressure (SBP) and blunted SBP dipping than those in quartile 4 when urinary sodium or potassium excretion rate was divided into day-to-night ratios (both P < 0.001). In multivariate analyses, lower day-to-night ratio of urinary sodium was independently linked to higher nocturnal SBP and blunted SBP dipping (linear regression coefficient (95% confidence interval [CI]): -6.89 (-9.48 to -4.31), and -3.64 (-5.48 to -1.80), respectively; both P < 0.001). Similarly, compared with the highest quartile of day-to-night ratio of urinary potassium excretion rate, linear regression coefficient (95% CI) for the lowest quartile was -5.60 (-8.13 to -3.07) for nocturnal SBP, and -2.47 (-4.28 to -0.67) for SBP dipping (both P < 0.001). Moreover, urine flow rate and concentrates of sodium or potassium in the urine were positively associated with urinary sodium or potassium excretion during daytime (P < 0.001).

Conclusion

A higher nocturnal BP and a blunted nocturnal BP dipping were both independently linked to a lower excretion of sodium or potassium during the day in patients with CKD. Furthermore, a decreased urine flow rate and a diminished capacity to concentrate sodium or potassium in the urine appear to be the key contributors to a low day-to-night ratio of urinary sodium excretion or potassium rate.

Gaps in hypertension care and control: a population-based study in low-income urban Medellin, Colombia

OBJECTIVES

To assess hypertension prevalence and the extent and associated factors of hypertension diagnosis, follow-up, treatment and control gaps in low-income urban Medellin, Colombia.

METHODS

We randomly sampled 1873 adults aged 35 or older. Unaware hypertensive individuals were defined as those without previous diagnosis whose average blood pressure was equal to or above 140/90 mmHg. For aware hypertensive patients, control was delimited as average blood pressure below 140/90 if under 59 years old or diabetic, and as less than 150/90 otherwise. We used logistic regression to identify care gap-associated factors.

RESULTS

Hypertension prevalence was 43.5% (95% CI 41.2-45.7). We found 28.2% aware and 15.3% unaware hypertensive individuals, which corresponds to a 35.1% (95% CI 31.9-38.5) underdiagnosis. This gap was determined by age, sex, education and lifestyle factors. 14.4% (95% CI 11.6-17.6) of aware hypertensive patients presented a follow-up gap, 93.4% (95% CI 90.9-95.2) were prescribed antihypertensive drugs, but 38.9% (95% CI 34.7-43.3) were not compliant. The latter was strongly associated with follow-up. The hypertension control gap in aware hypertensive patients, 39.0% (95% CI: 34.9-43.2), was associated with being older, having diabetes, weakly adhering to pharmacological treatment and receiving poor non-pharmacological advice. Overall, 60.4% (95% CI 57.0-63.8) of aware and unaware hypertensive participants had either diagnosed but uncontrolled or undiagnosed hypertension.

CONCLUSIONS

We found high hypertension prevalence coupled with, from an international perspective, encouraging awareness and control figures. Still, there remains ample room for improvement. Our findings can assist in designing integrated primary healthcare measures that further strengthen equitable and effective access to hypertension care and control.

Cost-Effectiveness of Improved Hypertension Management in India through Increased Treatment Coverage and Adherence: A Mathematical Modeling Study

Background:

Despite the availability of effective and affordable treatments, only 14% of hypertensive Indians have controlled blood pressure. Increased hypertension treatment coverage (the proportion of individuals initiated on treatment) and adherence (proportion of patients taking medicines as recommended) promise population health gains. However, governments and other payers will not invest in a large-scale hypertension control program unless it is both affordable and effective.

Objective:

To investigate if a national hypertension control intervention implemented across the private and public sector facilities in India could save overall costs of CVD prevention and treatment.

Methods:

We developed a discrete-time microsimulation model to assess the cost-effectiveness of population-level hypertension control intervention in India for combinations of treatment coverage and adherence targets. Input clinical parameters specific to India were obtained from large-scale surveys such as the Global Burden of Disease as well as local clinical trials. Input hypertensive medication cost parameters were based on government contracts. The model projected antihypertensive treatment costs, avoided CVD care costs, changes in disability-adjusted life year (DALYs) and incremental cost per DALY averted (represented as incremental cost-effectiveness ratio or ICER) over 20 years.

Results:

Over 20 years, at 70% coverage and adherence, the hypertension control intervention would avert 1.68% DALYs and be cost-saving overall. Increasing adherence (while keeping coverage constant) resulted in greater improvement in cost savings compared to increasing coverage (while keeping adherence constant). Results were most sensitive to the cost of antihypertensive medication, but the intervention remained highly cost-effective under all one-way sensitivity analyses.

Conclusion:

A national hypertension control intervention in India would most likely be budget neutral or cost-saving if the intervention can achieve and maintain high levels of both treatment coverage and adherence.

Effects of the Small-Sided Soccer Games on Blood Pressure in Untrained Hypertensive Adults: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

This systematic review with meta-analysis was conducted to assess the effects of small-sided games (SSGs)-based programs on the systolic and diastolic blood pressure of untrained hypertensive adults. The data sources utilized were Web of Science, Scopus, SPORTDiscus, and PubMed. The eligibility criteria were: (i) randomized controlled trials including a control group and an intervention group exclusively using soccer SSGs; (ii) intervention and control groups including an untrained hypertensive adult population; (iii) articles written in English; and (iv) only full-text and original articles. The database search initially identified 241 titles. From those, five articles were eligible for the systematic review and meta-analysis. The included randomized controlled studies involved five individual experimental groups and 88 participants, and 68 participants in the five control groups. The results showed a large and beneficial effect of SSG on systolic (ES = 1.69; 95% CI = 0.71 to 2.66; p = 0.001; I² = 85.2%; Egger’s test p = 0.101) and diastolic blood pressure (ES = 2.25; 95% CI = 1.44 to 3.06; p < 0.001; I² = 74.8%; Egger’s test p = 0.118) when compared to the control groups. The findings of the current systematic review and meta-analysis revealed consistent beneficial effects of recreational soccer SSGs on untrained men and women from the hypertensive population, although high levels of heterogeneity.

ACE Inhibitory and Antihypertensive Activities of Wine Lees and Relationship among Bioactivity and Phenolic Profile

Wine lees (WL) are by-products generated in the winemaking process. The aim of this study was to investigate the angiotensin-converting enzyme inhibitory (ACEi) activity, and the blood pressure (BP) lowering effect of WL from individual grape varieties. The relationship among their activities and phenolic profiles was also studied. Three WL, from Cabernet, Mazuela, and Garnacha grape varieties, were firstly selected based on their ACEi properties. Their phenolic profiles were fully characterized by UHPLC-ESI-Q-TOF-MS. Then, their potential antihypertensive effects were evaluated in spontaneously hypertensive rats (SHR). BP was recorded before and after their oral administrations (2, 4, 6, 8, 24, and 48 h) at a dose of 5 mL/kg bw. Cabernet WL (CWL) exhibited a potent antihypertensive activity, similar to that obtained with the drug Captopril. This BP-lowering effect was related to the high amount of anthocyanins and flavanols present in these lees. In addition, a potential hypotensive effect of CWL was discarded in normotensive Wistar-Kyoto rats. Finally, the ACEi and antihypertensive activities of CWL coming from a different harvest were confirmed. Our results suggest the potential of CWL for controlling arterial BP, opening the door to commercial use within the wine industry.

Mediating-Moderating Effect of Allostatic Load on the Association between Dietary Approaches to Stop Hypertension Diet and All-Cause and Cause-Specific Mortality: 2001-2010 National Health and Nutrition Examination Surveys

This secondary analysis of survey data examined mediating-moderating effects of allostatic load score (calculated using the Rodriquez method) on the association between nutrient-based Dietary Approaches to Stop Hypertension (DASH) diet score (Mellen Index) and the all-cause and cause-specific mortality risks among 11,630 adults ≥ 30 years of age from the 2001-2010 National Health and Nutrition Examination Surveys with no history of cardiovascular disease or cancer at baseline, and who were followed-up for ~9.35 years. Multivariable models were adjusted for demographic, socioeconomic, lifestyle, and health characteristics. All-cause, cardiovascular disease, and cancer-specific mortality rates were estimated at 6.5%, 1.1%, and 1.9%, respectively. The median DASH total score was 3.0 (range: 1-8) (with 78.3% scoring < 4.5), whereas the median allostatic load score was 3 (range: 0-9). The DASH diet, fiber, and magnesium were negatively correlated with allostatic load, whereas allostatic load predicted higher all-cause mortality, irrespective of the DASH diet. Whereas protein was protective, potassium increased all-cause mortality risk, irrespective of allostatic load. Potassium was protective against cardiovascular disease-specific mortality but was a risk factor for cancer-specific mortality. Although no moderating effects were observed, mediation by the allostatic load on cardiovascular disease-specific mortality was observed for DASH total score and selected component scores. Direct (but not indirect) effects of DASH through the allostatic load were observed for all-cause mortality, and no direct or indirect effects were observed for cancer-specific mortality. From a public health standpoint, the allostatic load may be a surrogate for the preventive effects of the DASH diet and its components on cardiovascular disease-specific mortality risk.

Genetics of Human Primary Hypertension: Focus on Hormonal Mechanisms

Increasingly, primary hypertension is being considered a syndrome and not a disease, with the individual causes (diseases) having a common sign-an elevated blood pressure. To determine these causes, genetic tools are increasingly employed. This review identified 62 proposed genes. However, only 21 of them met our inclusion criteria: (i) primary hypertension, (ii) two or more supporting cohorts from different publications or within a single publication or one supporting cohort with a confirmatory genetically modified animal study, and (iii) 600 or more subjects in the primary cohort; when including our exclusion criteria: (i) meta-analyses or reviews, (ii) secondary and monogenic hypertension, (iii) only hypertensive complications, (iv) genes related to blood pressure but not hypertension per se, (v) nonsupporting studies more common than supporting ones, and (vi) studies that did not perform a Bonferroni or similar multiassessment correction. These 21 genes were organized in a four-tiered structure: distant phenotype (hypertension); intermediate phenotype [salt-sensitive (18) or salt-resistant (0)]; subintermediate phenotypes under salt-sensitive hypertension [normal renin (4), low renin (8), and unclassified renin (6)]; and proximate phenotypes (specific genetically driven hypertensive subgroup). Many proximate hypertensive phenotypes had a substantial endocrine component. In conclusion, primary hypertension is a syndrome; many proposed genes are likely to be false positives; and deep phenotyping will be required to determine the utility of genetics in the treatment of hypertension. However, to date, the positive genes are associated with nearly 50% of primary hypertensives, suggesting that in the near term precise, mechanistically driven treatment and prevention strategies for the specific primary hypertension subgroups are feasible.

Two-year results of a community-based randomized controlled lifestyle intervention trial to control prehypertension and/or prediabetes in Thailand: a brief report

The aim of the study was to assess the 2-year effect of a community-based randomized controlled lifestyle intervention on glucose and blood pressure levels in Thailand. Participants (N=443, with prediabetes and/or prehypertension) received a six 2-hr group sessions lifestyle intervention (physical activity and nutrition) over 6 months. Measurements were at baseline, 12 months (89%) and at 24 months (84.7%). Statistically significant interaction effects on fasting plasma glucose and DBP at 12 months were not maintained at 24 months, while significant interaction effects were found on high-density lipoprotein and low-density lipoprotein cholesterol at 24 months. Improvements were found for fasting plasma glucose, SBP, DBP and total cholesterol, but no significant interaction effect was detected. The development of type 2 diabetes was higher in the control than in the intervention group, but it was not reaching significance (P=0.181), while 3.0% in the intervention group and 2.6% in the control group developed hypertension at 24 months. No significant group differences were found in psycho-behavioral variables. The lifestyle intervention did not provide additional benefits compared to the control group at 24-month follow-up. Trial registration number: TCTR20170721001.

Assessment of hypertension management and control: a registry-based observational study in two municipalities in Cuba

Background

To determine the prevalence of hypertension treatment and control among hypertensive patients in the Cuban municipalities of Cardenas and Santiago and to explore the main associated predictors.

Methods

Cross-sectional study, with multistage cluster sampling, conducted between February 2012 and January 2013 in two Cuban municipalities. We interviewed and measured blood pressure in 1333 hypertensive patients aged 18 years or older. Hypertension control was defined as blood pressure lower than 140/90 mmHg.

Results

The mean age ± standard deviation (SD) of participants was 59.8 ± 14 years, the mean systolic and diastolic blood pressure ± SD was 130.0 ± 14.4 and 83.1 ± 9.0 mmHg respectively. The majority of patients (91, 95%CI 90–93) were on pharmacological treatment, 49% with a combination of 2 or more classes of drugs. Among diagnosed hypertensive patients 58% (95%CI 55–61) had controlled hypertension. There was no association between hypertension control and gender, age and socio-economic condition. Levels of hypertension control depended on health area and control furthermore was positively associated with post-primary education, not being obese and white ethnicity: adjusted Odds Ratio (95% CI) 1.71 (1.26–2.34), 1.43 (1.09–1.88) and 1.41 (1.09–1.81) respectively.

Conclusions

The observed figures are outstanding at the international level and illustrate that hypertension treatment and control are achievable in a resource-constrained setting such as Cuba. The country’s primary health care approach and social equity in access to health care can be seen as key determinants of this success. Nevertheless, there is still room for improvement, as over a third of patients did not have controlled hypertension.

Dose-Related Antihypertensive Properties and the Corresponding Mechanisms of a Chicken Foot Hydrolysate in Hypertensive Rats

The antihypertensive properties of different doses of a chicken foot hydrolysate, Hpp11 and the mechanisms involved in this effect were investigated. Spontaneously hypertensive rats (SHR) were administered water, Captopril (50 mg/kg) or Hpp11 at different doses (25, 55 and 85 mg/kg), and the systolic blood pressure (SBP) was recorded. The SBP of normotensive Wistar-Kyoto (WKY) rats administered water or Hpp11 was also recorded. Additionally, plasmatic angiotensin-converting enzyme (ACE) activity was determined in the SHR administered Hpp11. Moreover, the relaxation caused by Hpp11 in isolated aortic rings from Sprague-Dawley rats was evaluated. Hpp11 exhibited antihypertensive activity at doses of 55 and 85 mg/kg, with maximum activity 6 h post-administration. At this time, no differences were found between these doses and Captopril. Initial SBP values of 55 and 85 mg/kg were recovered 24 or 8 h post-administration, respectively, 55 mg/kg being the most effective dose. At this dose, a reduction in the plasmatic ACE activity in the SHR was found. However, Hpp11 did not relax the aortic ring preparations. Therefore, ACE inhibition could be the mechanism underlying Hpp11 antihypertensive effect. Remarkably, Hpp11 did not modify SBP in WKY rats, showing that the decreased SBP effect is specific to the hypertensive state.

Nonpharmacologic management of hypertension: a multidisciplinary approach

PURPOSE OF REVIEW

Nonpharmacologic lifestyle modification interventions (LMIs), such as increasing physical activity, dietary modification, weight-loss, reducing alcohol consumption and smoking cessation, are effective strategies to lower resting blood pressures (BPs) in prehypertensive or hypertensive patients. However, the limited time shared between a physician and a patient is not adequate to instill an adoption of LMI. The purpose of this review is to therefore highlight evidence-based BP lowering, LMI strategies that can feasibly be implemented in clinical practices.

RECENT FINDINGS

Interventions focusing on modifying physical activity, diet, weight-loss, drinking and smoking habits have established greater efficacy in reducing elevated BP compared with providing guideline recommendations based on national guidelines. Alone greater reductions in BP can be achieved through programmes that provide frequent contact time with exercise, nutrition and/or wellness professionals. Programmes that educate individuals to lead peer support groups can be an efficient method of ensuring compliance to LMI.

SUMMARY

Evidence of a multidisciplinary approach to LMI is an effective and attractive model in managing elevated BP. This strategy is an attractive model that provides the necessary patient attention to confer lifestyle maintenance.

An information, education and communication module to reduce dietary salt intake and blood pressure among tea garden workers of Assam

OBJECTIVE

High salt diet increases blood pressure. Tea garden workers (TGW) of Assam, India have high (60.8%) prevalence of hypertension (HTN), which may be due to consumption of extra salt (salt as side dish) and salted tea at work place and home. The present study evaluated an information, education and communication (IEC) module to reduce salt intake and blood pressure among TGW.

METHODS

Two tea gardens (usual care and intervention) were selected at random covering a total population of 13,458. The IEC module consisting of poster display, leaflets, health rally, documentary show, individual and group discussion was introduced in the intervention garden targeting study participants, health care providers, key stake holders, school children and teachers. IEC intervention was continued for one year. Participants from usual care and intervention were followed at three monthly intervals and BP and other information were compared after one year.

RESULTS

A total of 393 study participants (Non intervention: 194; intervention: 199) were included. After one year of follow up, consumption of extra salt was reduced significantly in the intervention participants (66.3 vs. 45.5%, p=0.000). Intention to treat analysis revealed significant reduction in systolic [-6.4 (-8.6 to -4.2)] and diastolic [-6.9 (-8.1 to -5.7)] blood pressure after one year. Prevalence of HTN was reduced significantly (52.5 vs. 40.0%, p=0.02) among them.

CONCLUSIONS

Our IEC module created awareness about risk of hypertension associated with high salt intake and could reduce dietary salt intake and BP.

Development of a Hypertension Health Literacy Assessment Tool for use in primary healthcare clinics in South Africa, Gauteng

BACKGROUND

Hypertension is a universal risk factor for cardiovascular morbidity and mortality in both the ageing and obese populations and patients must be literate in hypertension health issues to participate actively in the management of their disease. Little research has been done to investigate hypertension health literacy levels among South Africans.

AIM

To develop a Hypertension Heath Literacy Assessment Tool to establish patients' comprehension of the health education they receive in primary healthcare (PHC) clinics in Tshwane, Gauteng, South Africa.

SETTING

PHC clinics in Tshwane, Gauteng, South Africa.

METHODS

The design was quantitative, descriptive and contextual in nature. The study population comprised health promoters who were experts in the field of health, documents containing hypertension health education content and individuals with hypertension. Participants were conveniently and purposefully selected. A modified Delphi technique was used to develop and validate the Hypertension Health Literacy Assessment Tool (HHLAT). To ensure validity and reliability of the HHLAT, the tool was administered to 195 participants concurrently with the Learning Ability Battery (LAB).

RESULTS

There was a strong positive (F = 76.0, p < 0.0001, R2 = 28.25%) correlation between the LAB and the HHLAT. The HHLAT indicated that only 37 (19%) of the patients with hypertension had poor hypertension health literacy levels.

CONCLUSION

The HHLAT is a valid tool that can be used in busy PHC clinics as it takes less than two minutes to administer. This tool can inform the healthcare worker on the depth of hypertension health education to be given to the patient, empowering the patient and saving time in PHC facilities.

Recognition and Management of Resistant Hypertension

Despite improvements in hypertension awareness and treatment, 30%-60% of hypertensive patients do not achieve BP targets and subsequently remain at risk for target organ damage. This therapeutic gap is particularly important to nephrologists, who frequently encounter treatment-resistant hypertension in patients with CKD. Data are limited on how best to treat patients with CKD and resistant hypertension, because patients with CKD have historically been excluded from hypertension treatment trials. First, we propose a consistent definition of resistant hypertension as BP levels confirmed by both in-office and out-of-office measurements that exceed appropriate targets while the patient is receiving treatment with at least three antihypertensive medications, including a diuretic, at dosages optimized to provide maximum benefit in the absence of intolerable side effects. Second, we recommend that each patient undergo a standardized, stepwise evaluation to assess adherence to dietary and lifestyle modifications and antihypertensive medications to identify and reduce barriers and discontinue use of substances that may exacerbate hypertension. Patients in whom there is high clinical suspicion should be evaluated for potential secondary causes of hypertension. Evidence-based management of resistant hypertension is discussed with special considerations of the differences in approach to patients with and without CKD, including the specific roles of diuretics and mineralocorticoid receptor antagonists and the current place of emerging therapies, such as renal denervation and baroreceptor stimulation. We endorse use of such a systematic approach to improve recognition and care for this vulnerable patient group that is at high risk for future kidney and cardiovascular events.

Effects of Lifestyle Modification on Telomerase Gene Expression in Hypertensive Patients: A Pilot Trial of Stress Reduction and Health Education Programs in African Americans

BACKGROUND

African Americans suffer from disproportionately high rates of hypertension and cardiovascular disease. Psychosocial stress, lifestyle and telomere dysfunction contribute to the pathogenesis of hypertension and cardiovascular disease. This study evaluated effects of stress reduction and lifestyle modification on blood pressure, telomerase gene expression and lifestyle factors in African Americans.

METHODS

Forty-eight African American men and women with stage I hypertension who participated in a larger randomized controlled trial volunteered for this substudy. These subjects participated in either stress reduction with the Transcendental Meditation technique and a basic health education course (SR) or an extensive health education program (EHE) for 16 weeks. Primary outcomes were telomerase gene expression (hTERT and hTR) and clinic blood pressure. Secondary outcomes included lifestyle-related factors. Data were analyzed for within-group and between-group changes.

RESULTS

Both groups showed increases in the two measures of telomerase gene expression, hTR mRNA levels (SR: p< 0.001; EHE: p< 0.001) and hTERT mRNA levels (SR: p = 0.055; EHE: p< 0.002). However, no statistically significant between-group changes were observed. Both groups showed reductions in systolic BP. Adjusted changes were SR = -5.7 mm Hg, p< 0.01; EHE = -9.0 mm Hg, p < 0.001 with no statistically significant difference between group difference. There was a significant reduction in diastolic BP in the EHE group (-5.3 mm Hg, p< 0.001) but not in SR (-1.2 mm Hg, p = 0.42); the between-group difference was significant (p = 0.04). The EHE group showed a greater number of changes in lifestyle behaviors.

CONCLUSION

In this pilot trial, both stress reduction (Transcendental Meditation technique plus health education) and extensive health education groups demonstrated increased telomerase gene expression and reduced BP. The association between increased telomerase gene expression and reduced BP observed in this high-risk population suggest hypotheses that telomerase gene expression may either be a biomarker for reduced BP or a mechanism by which stress reduction and lifestyle modification reduces BP.

TRIAL REGISTRATION

ClinicalTrials.gov NCT00681200.

The Effect of Self-Monitoring of Blood Pressure on Medication Adherence and Lifestyle Factors: A Systematic Review and Meta-Analysis

BACKGROUND

Self-monitoring of blood pressure (SMBP) can contribute to reduced blood pressure in people with hypertension. Potential mediators include increased medication, improved adherence, and changes in lifestyle factors including dietary change and increased physical activity. The objective of this review was to determine the effect of SMBP on medication adherence, medication persistence, and lifestyle factors in people with hypertension.

METHODS

Electronic bibliographic databases were searched through February 2014 to identify randomized controlled trials that compared SMBP to control/usual care in ambulatory hypertensive patients and reported medication or nonpharmacologic treatment adherence measures.

RESULTS

Twenty-eight trials with 7,021 participants fulfilled the inclusion criteria. Medication adherence was assessed in 25 trials (89%), dietary outcomes in 8 (29%), physical activity in 6 (21%), and medication persistence in 1 (4%). Blood pressure was assessed in 26 studies (93%). Follow-up ranged from 2 weeks to 12 months. Pooled results of 13 studies demonstrated a small but significant overall effect on medication adherence in favor of SMBP interventions (standardized mean difference 0.21, 95% CI 0.08, 0.34), with moderate heterogeneity (I2 = 43%). Standardized mean difference was used to express the size of intervention effect in each study relative to the variability observed, and was used to combine the results of studies where different measures of medication adherence were used. Where SMBP interventions had a significant effect on lifestyle factor change, the effect was unlikely to be clinically significant. Pooled results of 11 studies demonstrate a significant overall effect on diastolic blood pressure in favor of SMBP (weighted mean difference -2.02, 95% CI -2.93, -1.11), with low heterogeneity (I2 = 0%). A test for subgroup differences showed no difference when studies were grouped according to whether medication adherence was significantly improved or not.

CONCLUSIONS

SMBP may contribute to improvements in medication adherence in hypertensives. However, evidence for the effect of SMBP on lifestyle change and medication persistence is scarce, of poor quality, and suggests little clinically relevant benefit.

Prehypertension: Underlying pathology and therapeutic options

Prehypertension (PHTN) is a global major health risk that subjects individuals to double the risk of cardiovascular disease (CVD) independent of progression to overt hypertension. Its prevalence rate varies considerably from country to country ranging between 21.9% and 52%. Many hypotheses are proposed to explain the underlying pathophysiology of PHTN. The most notable of these implicate the renin-angiotensin system (RAS) and vascular endothelium. However, other processes that involve reactive oxygen species, the inflammatory cytokines, prostglandins and C-reactive protein as well as the autonomic and central nervous systems are also suggested. Drugs affecting RAS have been shown to produce beneficial effects in prehypertensives though such was not unequivocal. On the other hand, drugs such as β-adrenoceptor blocking agents were not shown to be useful. Leading clinical guidelines suggest using dietary and lifestyle modifications as a first line interventional strategy to curb the progress of PHTN; however, other clinically respected views call for using drugs. This review provides an overview of the potential pathophysiological processes associated with PHTN, abridges current intervention strategies and suggests investigating the value of using the "Polypill" in prehypertensive subjects to ascertain its potential in delaying (or preventing) CVD associated with raised blood pressure in the presence of other risk factors.

Efficacy of a church-based lifestyle intervention programme to control high normal blood pressure and/or high normal blood glucose in church members: a randomized controlled trial in Pretoria, South Africa

Background

In persons 15 years and above in South Africa the prevalence of pre-diabetes and diabetes has been estimated at 9.1% and 9.6%, respectively, and the prevalence of systolic prehypertension and hypertension, 38.2% and 24.6%, respectively. Elevated blood glucose and elevated blood pressure are prototype of preventable chronic cardiovascular disease risk factors.

Lifestyle interventions have been shown to control high normal blood pressure and/or high normal blood glucose.

Methods/Design

This study proposes to evaluate the efficacy of a community (church)-based lifestyle intervention programme to control high normal blood pressure and/or high normal blood glucose in church members in a randomized controlled trial in Gauteng, South Africa. The objectives are to: (1) measure non-communicable diseases profile, including hypertension and diabetes, health behaviours, weight management and psychological distress of church members; (2) measure the reduction of blood glucose and blood pressure levels after the intervention; (3) prevent the development of impaired glucose tolerance; (4) compare health behaviours, weight management and psychological distress, blood glucose and blood pressure levels between intervention and control groups, and within group during 6, 12, 24 and 36 months during and post intervention. The study will use a group-randomized design, recruiting 300 church members from 12 churches. Churches will be randomly assigned to experimental and control conditions.

Discussion

Lifestyle interventions may prevent from the development of high blood pressure and/or diabetes. The findings will impact public health and will enable the health ministry to formulate policy related to lifestyle interventions to control blood pressure and glucose.

Trial registration number

PACTR201105000297151

Supporting cardiovascular risk reduction in overweight and obese hypertensive patients through DASH diet and lifestyle education by primary care nurse practitioners

PURPOSE

To describe an intervention among overweight and obese hypertensive patients, encouraging Dietary Approaches to Stop Hypertension (DASH) diet and lifestyle changes, designed and led by a primary care nurse practitioner (NP).

DATA SOURCES

A pre- and postintervention quasi-experimental time-series design was implemented over 2 months. Intervention included three group classes and two individual counseling telephone calls. Forty-five hypertensive patients enrolled, with a mean age of 55 years and mean initial BMI of 32. Twenty-six (58%) completed the program. Standard instruments (Rapid Eating Assessment for Patients [REAP] and Partners in Health [PIH] questionnaires) were used to evaluate diet and lifestyle factors before and after the program.

CONCLUSIONS

Participants had statistically significant improvements in diet and lifestyle scores on both REAP and PIH questionnaires, as well as statistically significant weight loss (average 3.6 pounds lost) over the 2-month intervention period.

IMPLICATIONS FOR PRACTICE

This NP-led primary care intervention on diet and lifestyle showed early success in improving the health of overweight and obese hypertensive patients. Investment in NP-led diet and lifestyle counseling should be considered among high-risk patients in the primary care setting.

The association of genetic variations with sensitivity of blood pressure to dietary salt: A narrative literature review

Salt sensitivity of blood pressure (BP) is an independent risk factor for cardiovascular morbidity. Up to 50% of patients with essential hypertension are salt-sensitive, as manifested by a rise in BP with salt intake. Several genetic variations have been identified as being associated with salt sensitivity. The present study aimed to review the evidence on the effect of gene polymorphisms on the salt sensitivity of BP. We searched in PubMed website from 1990 to 2011, with the use of following keywords: "hypertension, dietary salt, polymorphisms, and blood pressure". The effect of sodium intake on BP differed by genotype at the genes of the renin-angiotensin system, aldosterone synthase, cytochrome p450 3A, epithelial sodium channel genes, genes of sympathetic nervous system, β-3 subunit of G-protein, alpha-adducin, endothelial nitric oxide synthase, Kallikrein-Kinin system. These approaches suggest that these polymorphisms may be potentially useful genetic markers of BP response to dietary salt. There is evidence that genetic predisposition modulates the BP response to diet. Therefore, diet and nutrition can mitigate or enhance the effects of genetic predisposition. Increasing our knowledge of this relationship can lead to individualized treatment and increased understanding of hypertension.

The role of angiotensin II in nonalcoholic steatohepatitis

Nonalcoholic fatty liver disease (NAFLD) is now considered the most prevalent chronic liver disease, affecting over 30% of the US adult population. NAFLD is strongly linked to insulin resistance and is considered the hepatic manifestation of the metabolic syndrome. Activation of the renin-angiotensin-aldosterone system (RAAS) is known to play a role in the hypertension observed in the metabolic syndrome and also is thought to play a central role in insulin resistance and NAFLD. Angiotensin II (AngII) is considered the primary effector of the physiological outcomes of RAAS signaling, both at the systemic and local tissue level. Herein, we review data describing the potential involvement of AngII-mediated signaling at multiple levels in the development and progression of NAFLD, including increased steatosis, inflammation, insulin resistance, and fibrosis. Additionally, we present recent work on the potential therapeutic benefits of RAAS and angiotensin II signaling inhibition in rodent models and patients with NAFLD.

Treatment of prehypertension: lifestyle and/or medication

Prehypertension is a warning to individuals with resting blood pressures between 120/80 mmHg and 139/89 mmHg of an insidious progression of blood pressure towards hypertensive levels (≥ 140/90 mmHg). Prehypertension is associated with increased cardiovascular risk and end organ damage compared with individuals who are normotensive. This review primarily focuses on internal and external factors associated with the prevalence of prehypertension. Elucidating all of the factors associated with a rise in resting blood pressure and comparing the effects of medication versus lifestyle changes may aid the clinician in developing a preventive and/or treatment strategy for each individual.

Patient trust in physicians and adoption of lifestyle behaviors to control high blood pressure

OBJECTIVE

To assess the relationship between patients' trust in their physician and self-reported adoption of lifestyle modification behaviors and medication adherence for control of hypertension.

METHODS

Longitudinal analysis of data from a randomized controlled trial of interventions to enhance hypertensive patients' adherence to medications and recommended lifestyle modifications. Two hundred patients were seen by 41 physicians at 14 urban primary care practices in Baltimore, Maryland, and followed for 12 months.

RESULTS

Seventy percent of patients reported complete trust in their physician. In adjusted analyses, patients with complete trust had higher odds of reporting that they were trying to lose weight (OR=2.27, 95% CI=1.38-3.74) than did patients with less than complete trust in their physician. Though not statistically significant, the odds of reporting trying to cut back on salt and engaging in regular exercise were greater in patients with complete trust. We observed no association for reports of medication adherence.

CONCLUSION

Trust in one's physician predicts attempts to lose weight among patients with hypertension, and may contribute to attempts to reduce salt and increase exercise.

PRACTICE IMPLICATIONS

Strengthening patient-physician relationships through efforts to enhance trust may be a promising strategy to enhance patients' engagement in healthy lifestyle behaviors for hypertension.

Adverse cardiac remodelling in spontaneously hypertensive rats: acceleration by high aerobic exercise intensity

In the present study it was hypothesized that voluntary aerobic exercise favours a pro-fibrotic phenotype and promotes adverse remodelling in hearts from spontaneously hypertensive rats (SHRs) in an angiotensin II-dependent manner. To test this, female SHRs at the age of 1 year were started to perform free running wheel exercise. Captopril was used to inhibit the renin-angiotensin system (RAS). Normotensive rats and SHRs kept in regular cages were used as sedentary controls. Training intensity, expressed as mean running velocity, was positively correlated with the left ventricular mRNA expression of TGF-β(1), collagen-III and biglycan but negatively correlated with the ratio of sarcoplasmic reticulum Ca(2+)-ATPase (SERCA)2a to Na(+)-Ca(2+) exchanger (NCX). A pro-fibrotic phenotype was verified by Picrosirius red staining. Sixty-seven per cent of SHRs performing free running wheel exercise died either spontaneously or had to be killed during a 6 month follow-up. In the presence of captopril, aerobic exercise did not show a similar positive correlation between training intensity and the expression of fibrotic markers. Moreover, in SHRs receiving captopril and performing free running wheel exercise, a training intensity-dependent reverse remodelling of the SERCA2a-to-NCX ratio was observed. None of these rats died spontaneously or had to be killed. In captopril-treated SHRs performing exercise, expression of mRNA for decorin, a natural inhibitor of TGF-β(1), was up-regulated. Despite these differences between SHR-training groups with and without captopril, positive training effects (lower resting heart rate and no progression of hypertension) were found in both groups. In conclusion, high aerobic exercise induces an angiotensin II-dependent adverse remodelling in chronic pressure overloaded hearts. However, high physical activity can potentially induce reverse remodelling in the presence of RAS inhibition.

High-antioxidant potatoes: acute in vivo antioxidant source and hypotensive agent in humans after supplementation to hypertensive subjects

Potatoes have the highest daily per capita consumption of all vegetables in the U.S. diet. Pigmented potatoes contain high concentrations of antioxidants, including phenolic acids, anthocyanins, and carotenoids. In a single-dose study six to eight microwaved potatoes with skins or a comparable amount of refined starch as cooked biscuits was given to eight normal fasting subjects; repeated samples of blood were taken over an 8 h period. Plasma antioxidant capacity was measured by ferric reducing antioxidant power (FRAP). A 24 h urine was taken before and after each regimen. Urine antioxidant capacity due to polyphenol was measured by Folin reagent after correction for nonphenolic interferences with a solid phase (Polyclar) procedure. Potato caused an increase in plasma and urine antioxidant capacity, whereas refined potato starch caused a decrease in both; that is, it acted as a pro-oxidant. In a crossover study 18 hypertensive subjects with an average BMI of 29 were given either six to eight small microwaved purple potatoes twice daily or no potatoes for 4 weeks and then given the other regimen for another 4 weeks. There was no significant effect of potato on fasting plasma glucose, lipids, or HbA1c. There was no significant body weight increase. Diastolic blood pressure significantly decreased 4.3%, a 4 mm reduction. Systolic blood pressure decreased 3.5%, a 5 mm reduction. This blood pressure drop occurred despite the fact that 14 of 18 subjects were taking antihypertensive drugs. This is the first study to investigate the effect of potatoes on blood pressure. Thus, purple potatoes are an effective hypotensive agent and lower the risk of heart disease and stroke in hypertensive subjects without weight gain.