Ambulatory blood pressure monitoring: recent evidence and clinical pharmacy applications

Biomechanical Sensing Systems for Cardiac Activity Monitoring

Cardiovascular disease is consistently ranked high among the causes of death on a global scale. Monitoring of cardiovascular signs throughout the course of a long period of time and in real time is necessary in order to discover anomalies and begin early intervention at the appropriate time. To this purpose, a significant amount of interest among researchers has been directed toward the creation of flexible sensors that may be worn or implanted and are capable of constant, immediate observation of a variety of main physiological indicators. The real-time readings of the heart and arteries' pressure fluctuations can be reflected directly by mechanical sensors, which are one of the many types of sensors. Potential benefits of mechanical sensors include excellent accuracy and considerable versatility. Capacitive, piezoresistive, piezoelectric, and triboelectric principles are the foundations of the four types of mechanical sensors that are discussed in this article as recent developments for the purpose of monitoring the cardiovascular system. The biomechanical systems that are present in the cardiovascular system are then detailed, along with their monitoring, and this includes blood and endocardial pressure, pulse wave, and heart rhythm. In conclusion, we examine the usefulness of the use of continuous health monitoring for the treatment of vascular disease and highlight the difficulties associated with its translation into clinical practice.

Mechanical Sensors for Cardiovascular Monitoring: From Battery-Powered to Self-Powered

Cardiovascular disease is one of the leading causes of death worldwide. Long-term and real-time monitoring of cardiovascular indicators is required to detect abnormalities and conduct early intervention in time. To this end, the development of flexible wearable/implantable sensors for real-time monitoring of various vital signs has aroused extensive interest among researchers. Among the different kinds of sensors, mechanical sensors can reflect the direct information of pressure fluctuations in the cardiovascular system with the advantages of high sensitivity and suitable flexibility. Herein, we first introduce the recent advances of four kinds of mechanical sensors for cardiovascular system monitoring, based on capacitive, piezoresistive, piezoelectric, and triboelectric principles. Then, the physio-mechanical mechanisms in the cardiovascular system and their monitoring are described, including pulse wave, blood pressure, heart rhythm, endocardial pressure, etc. Finally, we emphasize the importance of real-time physiological monitoring in the treatment of cardiovascular disease and discuss its challenges in clinical translation.

Chronotherapy in practice: the perspective of the community pharmacist

BACKGROUND

Optimising the time of drug administration in alignment with circadian rhythms to enhance the clinical effect or minimise/avoid adverse effects is referred to as chronotherapy. Pharmacists have a key role in providing medicine related information, including counselling about the optimal time for medication administration. Where applicable, the principles of chronotherapy should underlie this aspect of medication counselling. Despite significant developments in the science of chronotherapy for specific pharmacological treatments, the perspective of pharmacists about their understanding and application of these principles in practice has not been explored.

OBJECTIVE

To explore community pharmacist's viewpoints about and experience with the application of chronotherapy principles in practice.

SETTING

Community pharmacies within metropolitan Sydney in New South Wales, Australia.

METHODS

Semi-structured, face to face interviews with a convenience sample of community pharmacists were conducted. All interviews were audio-recorded, transcribed verbatim and thematically analyzed using a 'grounded theory' approach, given the novelty of this area. Main outcome measure Community pharmacists' awareness, current practice and future practice support requirements about the principles of chronotherapy.

RESULTS

Twenty-five semi-structured interviews were conducted. Most participants reported encountering cases where clinical decision making about suggesting appropriate times of drug administration to patients was needed. Their approach was mainly pragmatic rather than based on theoretical principles of circadian variation in drug disposition or on current or emerging evidence; thus there was an evidence practice chasm in some cases. However, most participants believed they have an important role to play in counselling patients about optimal administration times and were willing to enact such roles or acquire skills/competence in this area.

CONCLUSION

Community pharmacists contribute to the safe and effective use of medications in providing the patients with information on optimal timing of drug administration during counselling. Further education, practical training and access to information may help pharmacists in translating principles of chronotherapy into the practice.

Physician Acceptance of a Physician-Pharmacist Collaborative Treatment Model for Hypertension Management in Primary Care

Physician-pharmacist collaborative care (PPCC) is effective in improving blood pressure (BP) control, but primary care provider (PCP) engagement in such models has not been well-studied. The authors analyzed data from PPCC referrals to 108 PCPs, for patients with uncontrolled hypertension, assessing the proportion of referral requests approved, disapproved, and not responded to, and reasons for disapproval. Of 2232 persons with uncontrolled hypertension, PPCC referral requests were sent for 1516 (67.9%): 950 (62.7%) were approved, 406 (26.8%) were disapproved, and 160 (10.6%) received no response. Approval rates differed widely by PCP with a median approval rate of 75% (interquartile range, 41%-100%). The most common reasons for disapproval were: PCP prefers to manage hypertension (19%), and BP controlled per PCP (18%); 8% of cases were considered too complex for PPCC. Provider acceptance of a PPCC hypertension clinic was generally high and sustained but varied widely among PCPs. No single reason for disapproval predominated.

Amlodipine+benazepril is superior to hydrochlorothiazide+benazepril irrespective of baseline pulse pressure: subanalysis of the ACCOMPLISH trial

Pulse pressure (PP) is an independent risk factor for cardiovascular (CV) disease and death but few studies have investigated the effect of antihypertensive treatments in relation to PP levels before treatment. The Avoiding Cardiovascular Events Through Combination Therapy in Patients Living With Systolic Hypertension (ACCOMPLISH) trial showed that the combination of benazepril+amlodipine (B+A) is superior to benazepril+hydrochlorothiazide (B+H) in reducing CV events. We aimed to investigate whether the treatment effects in the ACCOMPLISH trial were dependent on baseline PP. High-risk hypertensive patients (n=11,499) were randomized to double-blinded treatment with single-pill combinations of either B+A or B+H and followed for 36 months. Patients were divided into tertiles according to their baseline PP and events (CV mortality/myocardial infarction or stroke) were compared. Hazard ratios (HRs) for the treatment effect (B+A over B+H) were calculated in a Cox regression model with age, coronary artery disease, and diabetes mellitus as covariates and were compared across the tertiles. The event rate was increased in the high tertile of PP compared with the low tertile (7.2% vs 4.4% P<.01). In the high and medium PP tertiles, HRs were 0.75 (95% confidence interval [CI], 0.60-0.95; P=.018) and 0.74 (CI, 0.56-0.98, P=.034), respectively, in favor of B+A. There was no significant difference between the treatments in the low tertile and no significant differences in treatment effect when comparing the HRs between tertiles of PP. B+A has superior CV protection over B+H in high-risk hypertensive patients independent of baseline PP although the absolute treatment effect is enhanced in the higher tertiles of PP where event rates are higher.

Treatment of hypertension with chronotherapy: is it time of drug administration?

OBJECTIVE

To review evidence for dosing antihypertensives at bedtime and possible cardiovascular risk reduction.

DATA SOURCES

A PubMed, EMBASE, and Cochrane Controlled Trials database literature search (1990-September 2014) limited to human subjects was performed using the search terms hypertension, chronotherapy, ambulatory blood pressure, morning administration, evening administration, and antihypertensives. Additional references were identified from literature citations.

STUDY SELECTION

All prospective studies assessing cardiovascular outcomes or comparing morning to evening administration of antihypertensives were selected.

DATA SYNTHESIS

Compared with morning administration, dosing one or more antihypertensive medications at bedtime helps induce a normal circadian blood pressure pattern and reduces the risk of cardiovascular disease morbidity and mortality in individuals with hypertension. Similar results have been reported in high-risk individuals with diabetes, chronic kidney disease, and resistant hypertension. A lack of diversity among studied populations and reliance on subgroup analyses are among the limitations of these data. All antihypertensive medications have not been studied in chronotherapy and do not uniformly achieve desired results. The most substantial evidence exists for medications affecting the renin-angiotensin-aldosterone system.

CONCLUSIONS

Despite growing evidence and promise as a cost-effective strategy for reducing cardiovascular risk, chronotherapy is not uniformly recommended in the treatment of hypertension. Careful selection of patients and antihypertensives for chronotherapy is required. Further investigation is needed to evaluate the definitive impact of chronotherapy on cardiovascular outcomes.