Roselle for hypertension in adults

Serum γ-glutamyltransferase levels and obesity status changes the risk of prehypertension in Chinese adults

Objective

It's well known that γ-Glutamyltransferase (γ-GGT) and obesity plays an important role in the development of preHT. However, the effect of γ-GGT on preHT in populations with different obesity status remains unclear.

Methods

From February 2014 to January 2018, a total of 20,368 participants were enrolled in this study after excluding those with hypertension and liver diseases. Fasting blood samples were collected to measure γ-GGT and blood lipid levels and glucose indices. Demographic and clinical parameters such as sex, age, height, weight, neck circumference (NC), waist circumference (WC), hip circumference (HC), and body fat ratio (BFR); and information on smoking and alcohol consumption were collected by trained medical professionals.

Results

Participants were divided into three groups based on obesity status. The prevalence of preHT was 83.5 % in the obesity group was higher than that in the overweight group (58.9 %) and the normal group (47.1 %). γ-GGT in different categories of obesity indices were significantly different, and higher obesity indices were found with higher γ-GGT levels. The interaction of γ-GGT and obesity indices such as NC, WC, HC, and BFR on the prevalence of preHT was significant (P = 0.028, 0.002, 0.007, and 0.034, respectively). Serum γ-GGT was found to be positively associated with preHT in participants with normal and overweight body mass indices.

Conclusion

Our results indicate that γ-GGT is a risk factor for preHT in participants who are nonobese, and that the obesity indices NC, WC, HC, BFR, and γ-GGT were contributing factors in increasing the risk of preHT.

Evaluating the potential of Hibiscus sabdariffa beverage to address the prevalence of iron deficiency in sub-Saharan Africa

The potential of Hibiscus sabdariffa L. beverage as a dietary iron source for sub-Saharan Africans was investigated. The target was to provide 6 mg of iron through 250 mL of the beverage daily. However, the iron content of the dried hibiscus calyces was determined to be 9.73 ± 0.31 mg/100 g and from that only ∼30% was extractable, resulting in 0.93 ± 0.19 mg Fe/250 mL of the selected beverage formulation. Therefore, ferrous sulfate was explored as a fortificant. The beverage contains polyphenols which could form non-absorbable chelation complexes with iron during digestion. Subsequently, the effect of polyphenols on the bioaccessibility of native and added iron was assessed using spectrophotometric methods. The presence of iron-polyphenol complexes in samples of the unfortified and fortified beverages, adjusted to pH 6.5 (pH at site of iron absorption in the gut) was established. However, only ∼25% of the added iron was found to be bound in the complex. It was shown that the viability of H. sabdariffa L. beverage as an iron source is impacted by extraction losses and the inhibitory effect of polyphenols. Nonetheless, if iron-polyphenol complexation was reduced/prevented then, a fortified hibiscus beverage could be a useful iron source.

Effect of the Combination of Hibiscus sabdariffa in Combination with Other Plant Extracts in the Prevention of Metabolic Syndrome: A Systematic Review and Meta-Analysis

Metabolic syndrome is a complex and multifactorial disorder associated with increased risk of cardiovascular disease and type 2 diabetes, exacerbated by a sedentary lifestyle and situations such as the COVID-19 pandemic. Recent studies have shown that consumption of fruits and vegetables high in polyphenols has a protective effect, reducing cardiovascular risk. Hibiscus sabdariffa (HS) in combination with other plant extracts has recently attracted scientists' attention due to its potential use in the treatment of metabolic syndrome. This systematic review and meta-analysis examines the effects of HS in combination with other plant extracts on the prevention of metabolic syndrome, exploring their synergistic effects and potential as therapeutic agents. For this purpose, a systematic search of randomized clinical trials (RCTs) was conducted in four different databases and the data obtained were then used for a meta-analysis. Initially, the titles and abstracts of 1368 studies were read. From these, 16 studies were examined closely for their eligibility, and finally, seven RCTs with 332 participants were included in both the meta-analysis and the qualitative analysis. Our results show that HS in combination with other plant extracts improved anthropometric parameters, blood pressure, and lipid profile (low density lipoprotein cholesterol and total cholesterol) compared to a placebo control group. It is important to note that although this meta-analysis suggests that HS in combination with other plant extracts may have a beneficial effect on cardiovascular parameters, further research is needed to determine the optimal dose and intake duration.

Roselle for hypertension in adults

BACKGROUND

Hypertension is considered to be a serious health problem worldwide. Controlling and lowering blood pressure are of significant benefit to people with hypertension because hypertension is a risk factor for stroke, heart disease, and cardiovascular disease. Roselle, the tropical plant Hibiscus sabdariffa, also commonly called sour tea or red tea, has been used as both a thirst-quenching drink and for medicinal purposes.

OBJECTIVES

To assess the effect of Roselle on blood pressure in people with primary hypertension.

SEARCH METHODS

For this update, the Cochrane Hypertension Information Specialist searched the following databases and trials registers for randomised controlled trials (RCTs): the Cochrane Hypertension Specialised Register (to 6 August 2021), Cochrane Central Register of Controlled Trials (CENTRAL; 2021, Issue 7), MEDLINE Ovid (1946 to 5 August 2021), Embase Ovid (1974 to 5 August 2021), ProQuest Dissertations & Theses (to 6 August 2021), Web of Science Clarivate (to 7 August 2021), Food Science and Technology Abstracts Clarivate (to 7 August 2021), the WHO International Clinical Trials Registry Platform (to 6 August 2021), and the US National Institutes of Health Ongoing Trials Register ClinicalTrials.gov (to 6 August 2021). We searched Google Scholar and OpenSIGLE. We also handsearched local and regional Chinese databases: CBM, CMCC, TCMLARS, CNKI, CMAC, and the Index to Chinese Periodical Literature (to 14 September 2020), as well as Thai databases (ThaiJO, CUIR, TDC, CMU e-Theses, TCTR) (to 3 October 2020). There were no language or publication date restrictions.

SELECTION CRITERIA

We sought RCTs evaluating the use of any forms of Roselle with placebo or no treatment in adults with hypertension. Our primary outcome was change in trough and/or peak systolic and diastolic blood pressure (SBP, DBP). Secondary outcomes were withdrawals due to adverse effects, change in pulse pressure, and change in heart rate.

DATA COLLECTION AND ANALYSIS

All search results were managed using Covidence and re-checked for the number of records, inclusion and exclusion of studies with Mendeley reference management software. We used standard methodological procedures expected by Cochrane. Two review authors worked independently in parallel for screening (titles and abstracts, and full reports), data extraction, risk of bias assessment, and assessment of the certainty of the evidence using the GRADE approach. Any disagreements were resolved by discussion or by consultation with the third review author if necessary. We presented mean difference (MD) of change in SBP and DBP with their corresponding 95% confidence interval (CI).

MAIN RESULTS

For this update, only one RCT with a parallel-group design involving 60 participants with type 2 diabetes mellitus fulfilled the inclusion criteria. This study investigated the effect of Roselle extract capsules (total dose of 5600 mg) compared with placebo (lactose) at eight weeks. The study was at low risk of selection bias, performance bias, and detection bias. Conversely, it was at high risk of attrition bias, reporting bias, and other bias (baseline imbalance). We have very little confidence in the effect estimate of Roselle on change-from-baseline in both SBP and DBP between the two groups. The MD of change in SBP was 1.65, 95% CI -7.89 to 11.19 mmHg, 52 participants, very low-certainty evidence. The MD of change in DBP was 4.60, 95% CI -1.38 to 10.58 mmHg, 52 participants, very low-certainty evidence. Our secondary outcomes of withdrawals due to adverse effects, change in pulse pressure, and change in heart rate were not reported. Due to the limited available data, no secondary analyses were performed (subgroup and sensitivity analysis).

AUTHORS' CONCLUSIONS

The evidence is currently insufficient to determine the effectiveness of Roselle compared to placebo for controlling or lowering blood pressure in people with hypertension. The certainty of evidence was very low due to methodological limitations, imprecision, and indirectness. There is a need for rigorous RCTs that address the review question.

Effects of Hibiscus sabdariffa L. on serum lipids: a systematic review and meta-analysis

ETHNOPHARMACOLOGICAL RELEVANCE

Prevention of cardiovascular disease by modifying its major risk factors, including serum cholesterol levels, is an important strategy. Hibiscus sabdariffa L. has been promoted for reducing cholesterol levels, but its reported impact on cholesterol levels has been inconsistent. The study aimed to assess systematically the evidence and quality of current research on the effect of Hibiscus sabdariffa L. on blood lipids and its adverse effects.

MATERIALS AND METHODS

Electronic databases were searched up to June 2013 for relevant randomised controlled trials (RCTs). Journals and conference proceedings were also searched. The quality of the selected trials was assessed using the Cochrane Risk of Bias Assessment Tool. The efficacy results of similar studies were pooled if they used the same comparator. Outcomes examined were levels of total cholesterol, high density lipoprotein cholesterol, low density lipoprotein cholesterol and triglycerides.

RESULTS

Six studies involving 474 subjects met our inclusion criteria. These studies varied in terms of the types of interventions, comparators used, and duration of trials. Overall, Hibiscus sabdariffa L. did not produce any significant effect on any of the outcomes examined, when compared with placebo, black tea or diet. With short-term use it is well tolerated.

CONCLUSIONS

The available evidence from RCTs does not support the efficacy of Hibiscus sabdariffa L. in lowering serum lipids. Further rigorously designed trials with larger sample sizes are warranted to confirm the effects of HS on serum lipids.

Hibiscus sabdariffa L. in the treatment of hypertension and hyperlipidemia: a comprehensive review of animal and human studies

The effectiveness of Hibiscus sabdariffa L. (HS) in the treatment of risk factors associated with cardiovascular disease is assessed in this review by taking a comprehensive approach to interpreting the randomized clinical trial (RCT) results in the context of the available ethnomedical, phytochemical, pharmacological, and safety and toxicity information. HS decoctions and infusions of calyxes, and on occasion leaves, are used in at least 10 countries worldwide in the treatment of hypertension and hyperlipidemia with no reported adverse events or side effects. HS extracts have a low degree of toxicity with a LD50 ranging from 2,000 to over 5,000mg/kg/day. There is no evidence of hepatic or renal toxicity as the result of HS extract consumption, except for possible adverse hepatic effects at high doses. There is evidence that HS acts as a diuretic, however in most cases the extract did not significantly influence electrolyte levels. Animal studies have consistently shown that consumption of HS extract reduces blood pressure in a dose dependent manner. In RCTs, the daily consumption of a tea or extract produced from HS calyxes significantly lowered systolic blood pressure (SBP) and diastolic blood pressure (DBP) in adults with pre to moderate essential hypertension and type 2 diabetes. In addition, HS tea was as effective at lowering blood pressure as the commonly used blood pressure medication Captropril, but less effective than Lisinopril. Total cholesterol, low-density lipoprotein cholesterol (LDL-C), and triglycerides were lowered in the majority of normolipidemic, hyperlipidemic, and diabetic animal models, whereas high-density lipoprotein cholesterol (HDL-C) was generally not affected by the consumption of HS extract. Over half of the RCTs showed that daily consumption of HS tea or extracts had favorable influence on lipid profiles including reduced total cholesterol, LDL-C, triglycerides, as well as increased HDL-C. Anthocyanins found in abundance in HS calyxes are generally considered the phytochemicals responsible for the antihypertensive and hypocholesterolemic effects, however evidence has also been provided for the role of polyphenols and hibiscus acid. A number of potential mechanisms have been proposed to explain the hypotensive and anticholesterol effects, but the most common explanation is the antioxidant effects of the anthocyanins inhibition of LDL-C oxidation, which impedes atherosclerosis, an important cardiovascular risk factor. This comprehensive body of evidence suggests that extracts of HS are promising as a treatment of hypertension and hyperlipidemia, however more high quality animal and human studies informed by actual therapeutic practices are needed to provide recommendations for use that have the potential for widespread public health benefit.

Roselle for hypertension in adults

BACKGROUND

Hypertension is considered a serious health problem worldwide. Controlling and lowering blood pressure have a significant benefit to the hypertensive patients because hypertension is a risk factor for stroke, heart disease and cardiovascular disease. A tropical plant called Roselle, or Red Sorrel in English-speaking countries, has been used both as a thirst-quenching drink and for medical purposes.

OBJECTIVES

To explore the effect of Roselle on blood pressure in hypertensive adult patients.

SEARCH STRATEGY

The following databases were searched (Date of most recent search was September 2009): - Cochrane Database of Systematic Reviews (2nd Quarter 2009) - DARE (2nd Quarter 2009) - Ovid MEDLINE (1950 to Present with Daily Update) - EMBASE (1980 to 2009 Week 22) - AMED (1985 to May 2009) - EBSCO CINAHL - BIOSIS (1969 to 2008) - AGRICOLA (1970 to May 2009) - Food Science and Technology Abstract (1969 to 2009 June Week 1) - International Pharmaceutical Abstracts - International Bibliographic Information on Dietary Supplements - Clinical Trials.gov and Current Controlled Trials - OpenSIGLE - Hand searching of journals - ISI Web of Knowledge

SELECTION CRITERIA

We sought randomised control trials (RCTs) evaluating use of any forms of Roselle with placebo or no treatment in hypertensive patients. Change in trough and/or peak systolic and diastolic blood pressure were primary outcomes. Secondary outcomes were withdrawals due to adverse effects, change of pulse pressure and change of heart rate.

DATA COLLECTION AND ANALYSIS

Two review authors (C Ngamjarus, CN and P Pattanittum, PP) independently scanned titles and abstracts, as well as independently screened the full reports of the potentially relevant studies. At each stage, the results were compared and disagreements were solved by discussion.

MAIN RESULTS

No studies were identified that met the inclusion criteria. However, one abstract of an ongoing study is likely to meet the inclusion criteria, when completed.

AUTHORS' CONCLUSIONS

There is insufficient evidence to support the benefit of Roselle for either controlling or lowering blood pressure in patients with hypertension. Based on the information of this review, there is a clear need to develop well-designed studies to assess the efficacy of Roselle on hypertensive patients.