Antihypertensive Combination Treatment: State of the Art

Self-care adherence and associated factors among hypertensive patients at Guraghe Zone, 2023

Background

Hypertension is the primary cause of cardiovascular disease and early mortality. Self-care is important for the prevention of hypertensive-related complications, and it was found to be necessary to determine the self-care adherence of hypertensive patients in Guraghe Zone, as there are limited findings in this area. The other reason for conducting this study was that there are certain variables related to self-care that have not been well studied, such as BMI, the number of antihypertensive medications, and the duration of antihypertensive drugs the patients are taking.

Objective

To assess self-care adherence and associated factors among hypertensive patients at Guraghe zone public hospitals.

Methods and materials

A multi-center institution-based cross-sectional study was conducted at selected Guraghe zone hospitals from May 20 to June 20, 2023. A systematic random sampling method was employed to select 370 participants. Hypertension self-care Activity Level Scale Effects (H-SCALE) was used to measure the self-care status. A binary logistic regression model was applied, and variables with a p-value <0.05 with a 95 % CI in the multivariable analysis were considered significant.

Results

The study evaluated the self-care adherence of 370 patients, and 50.8 % of patients had good self-care adherence. Normal BMI (AOR = 2.049, 95 % CI: 1.041, 4.033), starting antihypertensive in <5 years (AOR = 2.530, 95 % CI: 1.462, 4.381), patients taking three or more antihypertensive (AOR = 4.534, 95 % CI: 2.005, 10.252), absence of comorbidity (AOR = 1.758, 95 % CI: 1.030, 3.003), and strong social support (AOR = 3.842, 95 % CI: 1.994, 7.402) were significantly associated with good self-care.

Conclusion

and recommendation: Nearly half of patients with hypertension had good self-care adherence. BMI, antihypertensive duration, number of antihypertensive, comorbidity, and social support were variables that showed significant association with self-care adherence. Patients need to implement the lifestyle recommendations in addition to regular follow-up to prevent complications. Health-care facilities need to provide health education on the proper implementation of self-care recommendations.

Sakuranetin as a Potential Regulator of Blood Pressure in Spontaneously Hypertensive Rats by Promoting Vasorelaxation through Calcium Channel Blockade

Natural compounds, known for diverse pharmacological properties, have attracted attention as potential sources for hypertension treatment. Previous studies have revealed the hypotensive effect and vascular relaxation of prunetin, a natural compound derived from Prunus yedoensis. However, the potential blood pressure-lowering and vasorelaxant effects of sakuranetin, another representative compound found in plants belonging to the genus Prunus, have remained unexplored. We aimed to fill this gap by investigating the hypotensive and vasorelaxant effects of sakuranetin in rats. Results indicated that sakuranetin, particularly in the sakuranetin 20 mg/kg group, led to significant reductions in systolic blood pressure (SBP) and diastolic blood pressure (DBP) by -14.53 ± 5.64% and -19.83 ± 6.56% at 4 h after administration. In the sakuranetin 50 mg/kg group, the SBP and DBP decreased by -13.27 ± 6.86% and -16.62 ± 10.01% at 2 h and by -21.61 ± 4.49% and -30.45 ± 5.21% at 4 h after administration. In addition, we identified the vasorelaxant effects of sakuranetin, attributing its mechanisms to the inhibition of calcium influx and the modulation of angiotensin II. Considering its hypotensive and vasorelaxant effects, sakuranetin could potentially serve as an antihypertensive agent. However, further research is required to evaluate the safety and long-term efficacy.

Efficacy of single-pill combination in uncontrolled essential hypertension: A systematic review and network meta-analysis

This study aimed to evaluate the efficacy of single-pill combination (SPC) antihypertensive drugs in patients with uncontrolled essential hypertension. Through Searching Pubmed, EMBASE, the Cochrane Library, and Web of Science collected only randomized controlled trials on the efficacy of single-pill combination antihypertensive drugs in people with uncontrolled essential hypertension. The search period is from the establishment of the database to July 2022. The methodological quality of the included studies was assessed using the Cochrane Risk of Bias Assessment, and statistical analyses were performed using Review Manage 5.3 and Stata 15.1 software. This review ultimately included 32 references involving 16 273 patients with uncontrolled essential hypertension. The results of the network meta-analysis showed that a total of 11 single-pill combination antihypertensive drugs were included, namely: Amlodipine/valsartan, Telmisartan/amlodipine, Losartan/HCTZ, Candesartan/HCTZ, Amlodipine/benazepril, Telmisartan/HCTZ, Valsartan/HCTZ, Irbesartan/amlodipine, Amlodipine/losartan, Irbesartan/HCTZ, and Perindopril/amlodipine. According to SUCRA, Irbesartan/amlodipine may rank first in reducing systolic blood pressure (SUCRA: 92.2%); Amlodipine/losartan may rank first in reducing diastolic blood pressure (SUCRA: 95.1%); Telmisartan/amlodipine may rank first in blood pressure control rates (SUCRA: 83.5%); Amlodipine/losartan probably ranks first in diastolic response rate (SUCRA: 84.5%). Based on Ranking Plot of the Network, we can conclude that single-pill combination antihypertensive drugs are superior to monotherapy, and ARB/CCB combination has better advantages than other SPC in terms of systolic blood pressure, diastolic blood pressure, blood pressure control rate, and diastolic response rate. However, due to the small number of some drug studies, the lack of relevant studies has led to not being included in this study, which may impact the results, and readers should interpret the results with caution.

When blood pressure refuses to budge: exploring the complexity of resistant hypertension

Resistant hypertension, defined as blood pressure that remains above goal despite using three or more antihypertensive medications, including a diuretic, affects a significant proportion of the hypertensive population and is associated with increased cardiovascular morbidity and mortality. Despite the availability of a wide range of pharmacological therapies, achieving optimal blood pressure control in patients with resistant hypertension remains a significant challenge. However, recent advances in the field have identified several promising treatment options, including spironolactone, mineralocorticoid receptor antagonists, and renal denervation. In addition, personalized management approaches based on genetic and other biomarkers may offer new opportunities to tailor therapy and improve outcomes. This review aims to provide an overview of the current state of knowledge regarding managing resistant hypertension, including the epidemiology, pathophysiology, and clinical implications of the condition, as well as the latest developments in therapeutic strategies and future prospects.

Recent Developments in Drug Targets and Combination Therapy for the Clinical Management of Hypertension

Raised blood pressure is the most common complication worldwide that may lead to atherosclerosis and ischemic heart disease. Unhealthy lifestyles, smoking, alcohol consumption, junk food, and genetic disorders are some of the causes of hypertension. To treat this condition, numerous antihypertensive medications are available, either alone or in combination, that work via various mechanisms of action. Combinational therapy provides a certain advantage over monotherapy in the sense that it acts in multi mechanism mode and minimal drug amount is required to elicit the desired therapeutic effect. Such therapy is given to patients with systolic blood pressure greater than 20 mmHg and/or diastolic blood pressure exceeding 10 mmHg beyond the normal range, as well as those suffering from severe cardiovascular disease. The selection of antihypertensive medications, such as calcium channel blockers, angiotensin-converting enzyme (ACE) inhibitors, angiotensin receptor blockers (ARBs), and low-dose diuretics, hinges on their ability to manage blood pressure effectively and reduce cardiovascular disease risks. This review provides insights into the diverse monotherapy and combination therapy approaches used for elevated blood pressure management. In addition, it offers an analysis of combination therapy versus monotherapy and discusses the current status of these therapies, from researchbased findings to clinical trials.

Use of initial and subsequent antihypertensive combination treatment in the last decade: analysis of a large Italian database

OBJECTIVE

The aim of the study was to assess the use of antihypertensive combination treatment, both as the initial and as a subsequent therapeutic step, in a large Italian population.

METHODS

The residents of the Lombardy Region (Italy), aged 40 years or older, who were newly treated with antihypertensive drugs during 2012, 2015 and 2018 were identified and the drug treatment strategy (monotherapy and combination of two, three and more than three antihypertensive drugs) was assessed at treatment initiation, and after 6 months, 1, 2, and 3 years of treatment. Data were also analysed after stratification for demographic and clinical categories.

RESULTS

About 100 000 patients were identified for each cohort. Monotherapy was the most common initial treatment strategy (75%), followed by two-drug single-pill combination (16%), two-drug free combination (6%), and combination of at least three drugs (3%). Use of two and three or more antihypertensive drugs increased during follow-up and reached about 32% (two drugs) and 11% (>2 drugs) of the patients after 3 years from treatment initiation. Among patients prescribed a two-drug combination, the single-pill was the most common approach, whereas the use of the three-drug single-pill combination was extremely rare. There were no substantial differences in the use of combination treatment between the three cohorts and the results were similar in all demographic and clinical categories.

CONCLUSION

Our data show that in a real-life population use of antihypertensive drug combinations is low. They also show that, contrary to guideline recommendations, antihypertensive combination treatment did not show any noticeable increase in recent years.

Frequency-dependent depression of the NTS synapse affects the temporal response of the antihypertensive effect of auricular vagus nerve stimulation (aVNS)

OBJECTIVES

Auricular vagus nerve stimulation (aVNS) has recently emerged as a promising neuromodulation modality for blood pressure (BP) reduction due to its ease of use although its efficacy is still limited compared to direct baroreflex stimulation. Previous studies have also indicated that synaptic depression of nucleus tractus solitarius (NTS) in the baroreflex pathway depends on stimulus frequency. However, the nature of this frequency dependence phenomenon on antihypertensive effect has been unknown for aVNS. We aimed to investigate the antihypertensive effect of aVNS considering frequency-dependent depression characteristic in the NTS synapse. We explored NTS activation and BP reduction induced by aVNS and by direct secondary neuron stimulation (DS).

APPROACH

Both protocols were performed with recording of NTS activation and BP response with stimulation for each frequency parameter (2, 4, 20, 50, and 80 Hz).

MAIN RESULTS

The BP recovery time constant was significantly dependent on the frequency of DS and aVNS (DS - 2 Hz: 8.17 ± 4.98; 4 Hz: 9.73 ± 6.3; 20 Hz: 6.61 ± 3.28; 50 Hz: 4.93 ± 1.65; 80 Hz: 4.00 ± 1.43, p < 0.001, Kruskal-Wallis H-test / aVNS - 2 Hz: 4.02 ± 2.55; 4 Hz: 8.13 ± 4.05; 20 Hz: 6.40 ± 3.16; 50 Hz: 5.18 ± 2.37; 80 Hz: 3.13 ± 1.29, p < 0.05, Kruskal-Wallis H-test) despite no significant BP reduction at 2 Hz compared to sham groups (p > 0.05, Mann-Whitney U-test).

SIGNIFICANCE

Our observations suggest that the antihypertensive effect of aVNS is influenced by the characteristics of frequency-dependent synaptic depression in the NTS neuron in terms of the BP recovery time. These findings suggest that the antihypertensive effect of aVNS can be improved with further understanding of the neurological properties of the baroreflex associated with aVNS, which is critical to push this new modality for clinical interpretation.

Fabrication of a Shell-Core Fixed-Dose Combination Tablet Using Fused Deposition Modeling 3D Printing

Fixed-dose combinations (FDCs) achieve optimal goals for treatment with minimal side effects, decreased administration of large number of tablets, thus, greater convenience, and improved patient compliance. However, conventional FDCs do not have a guaranteed place in the future of patient-centered drug development because of the difficulty in achieving dose titration of each drug for individualized specific health needs and desired therapeutic outcomes. In the current study, FDCs of two antihypertensive drugs were fabricated with two distinct compartments using fused deposition modeling three-dimensional printing (FDM-3DP). Atorvastatin calcium and Amlodipine besylate loaded filaments were prepared by hot-melt extrusion. Shell-core FDC tablets were designed to have different infills for individualized dosing. Differential scanning calorimetry and powder X-ray diffraction revealed that both drugs were transformed into amorphous forms within the polymeric carriers. The fabricated tablets met the United States Pharmacopeia acceptance criteria for friability, content uniformity, and dissolution testing. The fabricated tablets were stable at room temperature with respect to drug content and thermal behavior over six months. This dynamic dosage form provides flexibility in dose titration and maintains the advantages of FDCs, thus achieving optimal therapeutic outcomes in different healthcare facilities.

Use of Perindopril Arginine/Indapamide/Amlodipine in the Management of Hypertension in Two Sub-Saharan African Island Countries of Madagascar and Mauritius

INTRODUCTION

Most patients with hypertension in sub-Saharan Africa require two or more drugs to control their blood pressure. Triple fixed-dose combination therapy of perindopril arginine/indapamide/amlodipine is more effective in lowering blood pressure, offers better target organ protection and has increased adherence compared to monotherapy and free combination therapy, and is safe to use. This observational study evaluates the effectiveness of perindopril arginine/indapamide/amlodipine in controlling blood pressure at least 1 month after treatment initiation and assesses patient- and physician- reported drug tolerance over a 3-month period in Madagascar and Mauritius.

METHODS

A total of 198 patients with hypertension in ambulatory care who had been on fixed-dose combination of perindopril arginine, indapamide, and amlodipine for at least 4 weeks were included. The main outcome measures were changes in systolic and diastolic blood pressure, attainment of blood pressure control under 140/90 mmHg and 130/80 mmHg, self-reported drug tolerance by the patient, and perceived drug tolerance by the treating physician. Data was collected at 1 month and 3 months.

RESULTS

Mean systolic blood pressure was significantly lower at the 1-month (- 3.4 mmHg, p = 0.002) and 3-month (- 8.5 mmHg, p < 0.0001) visits. Diastolic blood pressure also decreased significantly (- 2.4 mmHg at 1-month, p = 0.017 and - 5.4 mmHg at the 3-month visits, p < 0.0001). At 3 months, 80.4% of the patients attained blood pressure targets less than 140/90 mmHg and 42.7% attained targets less than 130/80 mmHg on the basis of their baseline blood pressure. Excellent drug tolerance was reported by more than 90% of patients and physicians at the 1-month visit and by more than 95% at the 3-month visit.

CONCLUSION

Triple fixed-dose therapy of perindopril arginine/indapamide/amlodipine continues to show additional blood pressure-lowering capacity even months after initiating the treatment in patients with hypertension in Madagascar and Mauritius. It is also well tolerated by patients with hypertension and assessed as safe to use by physicians.

Time-Dependent Effects of Individual and Combined Treatments With Nebivolol, Lisinopril, and Valsartan on Blood Pressure and Vascular Reactivity to Angiotensin II and Norepinephrine

Clinical guidelines suggest the combination of 2 drugs as a strategy to treat hypertension. However, some antihypertensive combinations have been shown to be ineffective. Therefore, it is necessary to determine whether differences exist between the results of monotherapy and combination therapy by temporal monitoring of the responses to angiotensin II and norepinephrine, which are vasoconstrictors involved in the development of hypertension. Thus, the purpose of this work was to determine the vascular reactivity to angiotensin II and norepinephrine in spontaneously hypertensive rat (SHR) aortic rings after treatment with valsartan, lisinopril, nebivolol, nebivolol-lisinopril, and nebivolol-valsartan for different periods of time. In this study, male SHR and Wistar Kyoto normotensive (WKY) rats were divided into 7 groups treated for 1, 2, and 4 weeks: (1) WKY + vehicle, (2) SHR + vehicle; (3) SHR + nebivolol; (4) SHR + lisinopril; (5) SHR + valsartan; (6) SHR + nebivolol-lisinopril; and (7) SHR + nebivolol-valsartan. Blood pressure was measured by the tail-cuff method, and vascular reactivity was determined from the concentration-response curve to angiotensin II and norepinephrine in aortic rings. The results showed that the combined and individual treatments reduced mean blood pressure at all times evaluated. All treatments decreased vascular reactivity to angiotensin II; however, in the case of lisinopril and nebivolol-lisinopril, the effect observed was significant up to 2 weeks. All treatments decreased the reactivity to norepinephrine up to week 4. These results show a time-dependent difference in vascular reactivity between the pharmacological treatments, with nebivolol-valsartan and nebivolol-lisinopril being both effective combinations. Additionally, the results suggest crosstalk between the renin-angiotensin and sympathetic nervous systems to reduce blood pressure and to improve treatment efficacy.

Position statement on use of pharmacological combinations in a single pill for treatment of hypertension by Argentine Federation of Cardiology (FAC) and Argentine Society of Hypertension (SAHA)

The present document provides scientific evidence reviewed and analysed by a group of specialist clinicians in hypertension that aims to give an insight into a pharmacological strategy to improve blood pressure control. Evidence shows that most hypertensive patients will need at least two drugs to achieve blood pressure goals. There is ample evidence showing that treatment adherence is inversely related to the number of drugs taken. Observational studies show that use of drug combinations to initiate treatment reduces the time to reach the treatment goal and reduces CVD, especially with single pill combinations (SPCs). This work, based on recommendations of the Argentine Federation of Cardiology and Argentine Society of Hypertension as a reference, aims to review the more recent evidence on SPC, and to serve as guidelines for health professionals in their clinical practice and to the wider use of SPCs for the treatment of hypertension. Evidence from clinical trials on the effectiveness and adverse effects of using SPCs are provided. An analysis is also made of the main contributions of SPCs in special populations, e.g., elderly and diabetic patients, and its use in high risk and resistant hypertension. The effects of SPCs on hypertensive-mediated organ damage is also examined. Finally, we provide some aspects to consider when choosing treatments in the economic context of Latin-America for promoting the most efficient use of resources in a scarce environment and to provide quality information to decision makers to formulate safe, cost-effective, and patient-centered health policies. Finally, future perspectives and limitations in clinical practice are also discussed.

Medication adherence in hypertension

: Suboptimal adherence to antihypertensive medication is a major contributor to poor blood pressure control. Several methods, direct or indirect, are available for measuring adherence, including the recently developed biochemical screening, although there is no gold-standard method routinely used in clinical practice to accurately assess the different facets of adherence. Adherence to treatment is a complex phenomenon and several of the barriers to adherence will need to be addressed at the healthcare system level; however, when looking at adherence from a more practical side and from the practitioner's perspective, the patient-practitioner relationship is a key element both in detecting adherence and in attempting to choose interventions tailored to the patient's profile. The use of single-pill combinations enabling simplification of treatment regimen, the implementation of a collaborative team-based approach and the development of electronic health tools also hold promise for improving adherence, and thus impacting cardiovascular outcomes and healthcare costs.

Application of supercritical fluid chromatography for separation and quantitation of 15 co-formulated binary anti-hypertensive medications using a single elution protocol

A facile supercritical fluid chromatography method is proposed to analyse 15 co-formulated binary anti-hypertensive drug combinations using a customized elution procedure. The effect of mobile phase composition, column back pressure and temperature was suitably optimized for adequate retention, analyte response and resolution. The chromatographic separation of the different drug combinations was performed on a DCPak poly(4-vinylpyridine) column (250 × 4.6 mm, 5 μm) at 125-bar pressure and 40°C using a photodiode array detector. A linear gradient of CO₂ and 0.1% formic acid in methanol provided the best elution conditions for all drug combinations. Baseline separation of the drugs was possible with resolution factor R_s ranging from 1.42 to 12.58. The method was validated for specificity, sensitivity, accuracy and precision, recovery and robustness. The limit of detection and limit of quantitation for aliskiren, amlodipine, atenolol, candesartan, hydrochlorothiazide, lisinopril, losartan, metoprolol, olmesartan, telmisartan and valsartan were in the range of 0.26-2.56 and 0.77-7.75 μg/mL, respectively. The thermodynamic study revealed that interactions of the drugs with the stationary phase were spontaneous as evident from the negative free energy values, and the separation process was enthalpy driven. The developed method was successfully employed to analyse these drugs in their co-formulated tablet formulations.

Evaluation of Blood Pressure Control and Associated Factors among Patients with Hypertension in Iraq: A Prospective Cross-sectional Study

BACKGROUND

Uncontrolled blood pressure (BP) is a major contributor to cardiovascular disease-related morbidity and mortality. However, evidence regarding the rate and factors associated with uncontrolled BP in Iraq is scarce. The objectives of this study were a) to assess the magnitude of and factors associated with patient BP control and b) to investigate the patient-level prescribing patterns of antihypertensive medications, in a large Iraqi hospital.

MATERIALS AND METHODS

A prospective, cross-sectional study was conducted in the primary care centers of Al-Yarmouk Hospital in Baghdad, Iraq, between April 2018 and August 2018. Eligible patients answered standard survey questions and had their BP measured. Controlled BP was defined as <130/80mm Hg for patients with diabetes and/or chronic kidney disease and <140/90mm Hg for other populations.

RESULTS

During the study period, 300 patients were included; of which, 67.3% were female. The average age was 57.6 (9.2) years (range, 25-79 years). Among the 300 patients included, only 38.7% had controlled BP. In univariate analysis, poorly controlled BP was not associated with education, employment, smoking, comorbid conditions excluding diabetes, and therapeutic regimen used. In contrast, the strongest predictors of uncontrolled BP were age <60 years, male sex, and diabetes mellitus. The majority were prescribed monotherapy (53.0%), followed by dual therapy (38.7%), and triple therapy (8.3%). Angiotensin II receptor blockers or angiotensin-converting enzyme inhibitors were the most commonly prescribed medications at 74.7%, followed by beta-blockers at 29.3%, calcium channel blockers at 28.0%, and diuretics at 23.0%.

CONCLUSION

BP control was suboptimal. Effective feasible strategies should be implemented to increase BP control in Iraq to reduce hypertension-related complications.

Fixed Versus Free Combinations Of Antihypertensive Drugs: Analyses Of Real-World Data Of Persistence With Therapy In Italy

PURPOSE

To analyse the pattern of use and cost of antihypertensive drugs in new users in an Italian population, and explore the patient/treatment factors associated with the risk of therapy discontinuation.

PATIENTS AND METHODS

In this retrospective study, information was collected from a population-based electronic primary-care database. Persistence with medication use 1 year from therapy initiation was evaluated for each user using the gap method. Each new user was classified according to his/her pattern of use as: "continuer", "discontinuer" "switching" or "add-on". A Cox regression model was used to analyse the factors influencing therapy discontinuation. Primary-care costs comprised specialists' visits, diagnostic procedures and pharmacologic therapies.

RESULTS

Among 14,999 subjects included in persistence analyses, 55.1% of cases initially started on monotherapy were classified as discontinuers vs 36.5% of cases taking combination therapy (42.3% vs 32.7%, respectively, for free and fixed combinations, P < 0.01). Old age, high cardiovascular risk and being in receipt of fixed-combination therapy were associated with greater persistence. Overall, the primary-care cost/person/year of hypertension management was ~€95.3 (IQR, 144.9). The monotherapy cost was €88 per patient (IQR, 132.9), and that for combination therapy was €151±148.3. The median cost/patient with a fixed combination was lower than that for a free combination (€98.4 (IQR, 155.3) and €154.9 (IQR, 182.6), respectively).

CONCLUSION

The initial type of therapy prescribed influences persistence. Prescribing fixed combinations might be a good choice as initial therapy.

Combination therapy in the treatment of hypertension

Hypertension is a major preventable risk factor for atherosclerosis and ischemic heart disease. Although modern and effective antihypertensive drugs are available, most patients remain with a suboptimal blood pressure control. Most hypertensive patients will need a combination of antihypertensive agents to achieve the therapeutic goals – recent guidelines recommend initiating treatment with two drugs in those patients with a systolic blood pressure >20 mmHg and/or a diastolic blood pressure >10 mmHg above the goals, and in those patients with high cardiovascular risk. In addition, approximately 25% of patients will require three antihypertensive agents to achieve the therapeutic targets. In this review, we analyse the latest information available regarding the treatment of hypertension with combination therapy.

Comparison of therapy persistence for fixed versus free combination antihypertensives: a retrospective cohort study

OBJECTIVES

The aim of the study was to compare therapy persistence among patients who started with one of three drug regimens: a monotherapy, or combination therapy either as a fixed combination (ie, 'single pill') or as a free combination (ie, two separate antihypertensive agents).

DESIGN

In a secondary data analysis, we used descriptive statistics and multivariate logistic regression to measure the effect of the three therapy regimens on therapy persistence over 4 years.

SETTING

Prescription data from a large German statutory health insurance provider.

PARTICIPANTS

All patients who started with a new antihypertensive therapy in 2007 or 2008 (n=8032) were included and followed for 4 years.

PRIMARY OUTCOME MEASURE

Therapy persistence, defined as receiving a refill prescription no later than within 180 days.

RESULTS

The persistence rates after 4 years were nearly identical among patients who started with a monotherapy (40.3%) or a fixed combination of two drugs (39.8%). However, significantly more patients who started with free-drug combinations remained therapy persistent (56.4%), resulting in an OR of 2.00 (95% CI 1.6 to 2.5; p<0.0001) for free combinations versus fixed combinations. This trend was observed in all age groups and for men and women. At the end of the study period, the number of different antihypertensive agents was still similar between patients who started with a fixed combination (2.41) and patients who started with a free combination (2.28).

CONCLUSIONS

While single-pill combinations make it easier to take different drugs at once, the risk is high that these several substances are stopped at once. Therapy persistence was significantly better for patients who started with a free-drug combination without taking much fewer different antihypertensive drugs as those with a fixed combination.

Bioequivalence study between a fixed-dose single-pill formulation of nebivolol plus hydrochlorothiazide and separate formulations in healthy subjects using high-performance liquid chromatography coupled to tandem mass spectrometry

Systemic arterial hypertension is a major risk factor for cerebrovascular disease. Therefore, adequate control of blood pressure is of enormous importance. One of the many fixed-dose single-pill antihypertensive formulations available on the market is the combination of nebivolol and hydrochlorothiazide. The objective of this study was to develop two distinct high-performance liquid chromatography coupled to tandem mass spectrometry methods to simultaneously quantify nebivolol and hydrochlorothiazide in human plasma. The methods were employed in a bioequivalence study, the first assay involving a nebivolol fixed-dose single-pill formulation based on healthy Brazilian volunteers. Nebilet HCT™ (nebivolol 5 mg + hydrochlorothiazide 12.5 mg tablet, manufactured by Menarini) was the test formulation. The reference formulations were Nebilet™ (nebivolol 5 mg tablet, manufactured by Menarini) and Clorana™ (hydrochlorothiazide 25 mg tablet, manufactured by Sanofi). For both analytes, liquid-liquid extraction was employed for sample preparation and the chromatographic run time was 3.5 min. The limits of quantification validated were 0.02 ng/mL for nebivolol and 1 ng/mL for hydrochlorothiazide. Since the 90% CI for C_max , AUC_(0-last) and AUC_(0-inf) individual test/reference ratios were within the 80-125% interval indicative of bioequivalence, it was concluded that Nebilet HCT™ is bioequivalent to Nebilet™ and Clorana™.

How does prescribing for antihypertensive products stack up against guideline recommendations? An Australian population-based study (2006-2014)

AIMS

We describe choice of first-line antihypertensive drug therapy and uptake of fixed-dose combinations (FDCs) in Australia, and investigate the impact of initiation on FDCs and other non-recommended first-line therapies on treatment discontinuation.

METHOD

This was a population-based retrospective cohort study using a random 10% sample of persons dispensed an Australian Pharmaceutical Benefits Scheme listed medicine from 1 July 2005 to 30 June 2014. The primary outcomes were adherence to Australian recommendations at initiation of antihypertensive therapy, discontinuation of initial therapy and discontinuation of any therapy in the first year after initiation.

RESULTS

In our sample of 55 937 persons initiating therapy, 42.0% did so outside Australian recommendations, including not initiating on recommended monotherapy (26.3%) and not initiating on the lowest recommended dose (30.6%). Only 1.7% of individuals who were dispensed an FDC established therapy on the free combination regimen (as recommended) prior to switching. After adjusting for covariates, persons initiating on non-recommended monotherapy (OR = 2.64, 95% CI 2.47-2.83) or FDCs of two or more antihypertensives (OR = 1.42, 95% CI 1.30-1.55), were more likely to discontinue all antihypertensive drug treatment in the first year compared to persons initiating on recommended monotherapy.

CONCLUSION

More than half of antihypertensive initiators conformed to Australian guidelines. Initiation on FDCs and other non-recommended treatments was associated with lower persistence on antihypertensive therapy in the first year. Long-term effectiveness and outcomes may be enhanced by initiating with low dose monotherapy.