The Role of Pharmaceutical Innovation in Clinical Practice Guidelines for Chronic Diseases

Background

Over the last 25 years, clinical practice guidelines have emerged as a means to standardize and improve care. As pharmaceutical innovations develop, guidelines are updated to incorporate new interventions. However, the extent to which pharmacotherapies are represented as treatment options in guideline recommendations has not been well elucidated. This study aimed to quantify the role pharmacotherapy has played in clinical practice guidelines across a range of chronic diseases over the past 20 years.

Methods

Clinical practice guidelines published from 2000 to 2021 were identified for five chronic diseases: ischemic heart disease (IHD), non-small cell lung cancer (NSCLC), chronic obstructive pulmonary disease (COPD), Alzheimer's disease (AD), and type 2 diabetes (T2D). Guidelines were reviewed and data on treatment recommendations were collected, including the type of intervention, line of therapy, and, for pharmacotherapies, year of regulatory approval and year of inclusion in guidelines.

Results

In total, 92 clinical practice guidelines were reviewed. Among the 184 discrete recommended interventions across the five disease areas, 146 (79.3%) were pharmacotherapies, 21 (11.4%) were behavioral modifications, 6 (3.3%) were surgical interventions, and 11 (6%) were other interventions. Across guidelines, when a line of therapy was specified, behavioral modifications and pharmacotherapies were most frequently recommended as first-line interventions, whereas surgical interventions were more often recommended for subsequent lines of treatment. The time from regulatory approval of novel pharmacotherapies to inclusion in guideline recommendations varied considerably by disease area and geography.

Conclusions

Across the reviewed disease areas, behavioral interventions and pharmacotherapies are shown to be critical components of clinical practice. Over the last 20 years, novel pharmaceutical innovations have been incorporated into clinical practice guideline recommendations; however, with varying speeds of adoption. Given the increasing pace of pharmacologic innovation, timely updates of clinical practice guidelines are critical to evolving the standard of care and practicing evidence-based medicine.

Is Value Portable? An Examination of Contextual and Practical Considerations that Affect the Transferability of Value Assessments between Settings

Objectives

The extent to which value assessments are uniquely deployed in any given geographic setting is variable. Increasingly, markets are seeking insights from external health technology assessments (HTAs) to assist with decisions surrounding the adoption of new technologies. We reviewed the environment, infrastructure, and practice of value assessment in six countries, with a focus on how these elements influence the transferability of value assessments between settings.

Methods

We reviewed the diverse settings in which six organizations conducting HTA operate, and explored how differences might affect the transferability of value assessment. We focused attention on Australia’s Pharmaceutical Benefits Advisory Committee, China’s National Center for Medicine and HTA, Germany’s Institut für Qualität und Wirtschaftlichkeit im Gesundheitswesen, Japan’s Center for Outcomes Research and Economic Evaluation for Health (Core 2 Health), the National Institute for Health and Care Excellence in England and Wales, and the Institute for Clinical and Economic Review in the United States.

Results

HTA is adopted to address unique objectives for a given health system and is tailored to support local standards and preferences. Some elements of a value assessment, such as evidence on clinical effectiveness, may be more transferable than others. It is challenging to appropriately adjust external assessments to the local context.

Conclusions

Contextual differences influence both the role and application of HTA. These differences limit the transferability of value assessments from one setting to another. De novo appraisals, customized to the local decision context, are the ideal approach to determinations about value.

Role of Vascular Adaptation in Determining Systolic Blood Pressure in Young Adults

Background

Two individuals can have a similar pulse pressure (PP) but different levels of systolic blood pressure (SBP), although the underlying mechanisms have not been described. We hypothesized that, for a given level of PP, differences in SBP relate to peripheral vascular resistance (PVR); and we tested this hypothesis in a large cohort of healthy young adults.

Methods and Results

Demographic, biochemical, and hemodynamic data from 3103 subjects were available for the current analyses. In both men and women, for a given level of PP, higher SBP was associated with significantly higher body weight, body mass index, heart rate, and PVR (P<0.05 versus those with lower BP for all comparisons). Moreover, stratifying individuals by quartiles of PP and PVR revealed a stepwise increase in SBP from the lowest to highest quartile for each variable, with the highest SBP occurring in those in the highest quartile of both PP and PVR (P<0.001 for overall trend for both sexes). PVR was also increased with increasing tertile of minimum forearm vascular resistance, in both men (P=0.002) and women (P=0.03).

Conclusions

Increased PVR, mediated in part through altered resistance vessel structure, strongly associates with the elevation of SBP for a given level of PP in young adults. An impaired ability to adapt PVR appropriately to a given level of PP may be an important mechanism underlying elevated SBP in young adults.

Stiffening and ventricular-arterial interaction in the ascending aorta using MRI: ageing effects in healthy humans

Supplemental Digital Content is available in the text

Objectives:

The aim of this study was to investigate the effect of age and sex on _nPWV and _ndI in the ascending aorta of healthy humans.

Background:

Local pulse wave velocity (_nPWV) and wave intensity (_ndI) in the human ascending aorta have not been studied adequately, because of the need for invasive pressure measurements. However, a recently developed technique made the noninvasive determination of _nPWV and _ndI possible using measurements of flow velocity and arterial diameter.

Methods:

Diameter and flow velocity were measured at the level of the ascending aorta in 144 healthy participants (aged 20–77 years, 66 men), using MRI. _nPWV, _ndI parameters; forward (FCW); backward (BCW) compression waves, forward decompression wave (FDW), local aortic distensibility (_nD_s) and reflection index (_nRI) were calculated.

Results:

_nPWV increased significantly with age from 4.7 ± 0.3 m/s for those 20–30 years to 6.4 ± 0.2 m/s for those 70–80 years (P < 0.001) and did not differ between sexes. _nD_s decreased with age (5.3 ± 0.5 vs. 2.6 ± 0.2 10⁻⁵ 1/Pa, P < 0.001) and _nRI increased with age (0.17 ± 0.03 vs. 0.39 ± 0.06, P < 0.01) for those 20–30 and 70–80 years, respectively. FCW, BCW and FDW decreased significantly with age by 86.3, 71.3 and 74.2%, respectively (P < 0.001), all compared to the lowest age-band.

Conclusion:

In healthy humans, ageing results in stiffer ascending aorta, with increase in _nPWV and decrease in _nD_s. A decrease in FCW and FDW indicates decline in left ventricular early and late systolic functions with age in healthy humans with no differences between sexes. _nRI is more sensitive than BCW in establishing the effects of ageing on reflected waves measured in the ascending aorta.

Influence of the central-to-peripheral arterial stiffness gradient on the timing and amplitude of wave reflections

In individuals with compliant aortas, peripheral muscular artery stiffness exceeds central elastic artery stiffness. With aging, central stiffness increases with little change in peripheral stiffness, resulting in a reversal of the normal stiffness gradient. This reversal may reduce the wave reflection amplitude due to the movement of the major 'effective' reflection site further from the heart. To test this phenomenon, we investigated the relationship among arterial stiffness gradients (normal and reversed), wave reflection amplitude and reflection site distance. Subjects aged ⩾50 years were recruited from the Anglo-Cardiff Collaborative Trial. Central stiffness was assessed by carotid-femoral pulse wave velocity (cfPWV). In Study 1, peripheral PWV was also measured in the arm (carotid-radial pulse wave velocity) and, in Study 2, in the leg (femoral-dorsalis pedis). Reflection site distance was calculated from cfPWV and the reflected wave Tr. Subjects were dichotomized into those with a normal stiffness gradient (peripheral >central PWV) or a reversed gradient (peripheral Collapse

Key Words

• arterial stiffness gradient
• augmentation index
• pulse wave velocity
• wave reflection
• central pulse pressure

Collapse

MESH Headings

• Aged
• Aorta/physiology
• Arm/blood supply
• Blood Pressure/physiology
• Carotid Arteries/physiology
• Female
• Femoral Artery/physiology
• Humans
• Leg/blood supply
• Male
• Middle Aged
• Pulsatile Flow/physiology
• Pulse Wave Analysis
• Vascular Stiffness/physiology

Collapse

Grants

• FS/07/001/21990 British Heart Foundation
• FS/12/8/29377 British Heart Foundation

Collapse

Affiliation(s)

Stacey S Hickson Division of Experimental Medicine and Immunotherapeutics, Department of Medicine, University of Cambridge, Cambridge, UK
Wilmer W Nichols Division of Cardiovascular Medicine, Department of Medicine, University of Florida, Gainesville, FL, USA
Yasmin Division of Experimental Medicine and Immunotherapeutics, Department of Medicine, University of Cambridge, Cambridge, UK
Barry J McDonnell Department of Biomedical Sciences, School of Health Sciences, Cardiff Metropolitan University, Cardiff, UK
John R Cockcroft Department of Cardiology, Wales Heart Research Institute, Cardiff University, Cardiff, UK
Ian B Wilkinson Division of Experimental Medicine and Immunotherapeutics, Department of Medicine, University of Cambridge, Cambridge, UK
Carmel M McEniery Division of Experimental Medicine and Immunotherapeutics, Department of Medicine, University of Cambridge, Cambridge, UK

Collapse

Age-related changes of regional pulse wave velocity in the descending aorta using Fourier velocity encoded M-mode

Aortic pulse wave velocity (PWV) is an independent determinant of cardiovascular risk. Although aortic stiffening with age is well documented, the interaction between aging and regional aortic PWV is still a debated question. We measured global and regional PWV in the descending aorta of 56 healthy subjects aged 25-76 years using a one-dimensional, interleaved, Fourier velocity encoded pulse sequence with cylindrical excitation. Repeatability across two magnetic resonance examinations (n = 19) and accuracy against intravascular pressure measurements (n = 4) were assessed. The global PWV was found to increase nonlinearly with age. The thoracic aorta was found to stiffen the most with age (PWV [thoracic, 20-40 years] = 4.7 ± 1.1 m/s; PWV [thoracic, 60-80 years] = 7.9 ± 1.5 m/s), followed by the mid- (PWV [mid-abdominal, 20-40 years] = 4.9 ± 1.3 m/s; PWV [mid-abdominal, 60-80 years] = 7.4 ± 1.9 m/s) and distal abdominal aorta (PWV [distal abdominal, 20-40 years] = 4.8 ± 1.4 m/s; PWV [distal abdominal, 60-80 years] = 5.7 ± 1.4 m/s). Good agreement was found between repeated magnetic resonance measurements and between magnetic resonance PWVs and the gold-standard. Fourier velocity encoded M-mode allowed to measure global and regional PWV in the descending aorta. There was a preferential stiffening of the thoracic aorta with age, which may be due to progressive fragmentation of elastin fibers in this region.

The relationship of age with regional aortic stiffness and diameter

OBJECTIVES

The purpose of this study was to determine the impact of age on regional aortic pulse wave velocity (aPWV).

BACKGROUND

aPWV is an independent predictor of cardiovascular risk and increases exponentially with age. However, it is unclear whether such changes occur uniformly along the length of the aorta or vary by region.

METHODS

A total of 162 subjects, aged 18 to 77 years and free of cardiovascular disease and medication, were recruited from the Anglo-Cardiff Collaborative Trial. Cine phase contrast magnetic resonance imaging was performed at 5 aortic levels. Systolic diameter and average blood flow were measured at each level and regional aPWV (regional aPWV measured by cine phase contrast magnetic resonance imaging) determined in 4 aortic segments: the arch (R1), the thoracic-descending aorta (R2), mid-descending aorta (R3), and the abdominal aorta (R4) and across the entire aorta.

RESULTS

Regional PWV measured by cine phase contrast magnetic resonance imaging values increased from the valve to the bifurcation in the 4 segments (PWV-R1- PWV-R4: 4.6 ± 1.5 m/s, 5.5 ± 2.0 m/s, 5.7 ± 2.3 m/s, 6.1 ± 2.9 m/s, respectively) and did not differ between genders. The greatest age-related difference in stiffness occurred in the abdominal aorta (+0.9 m/s per decade, p < 0.001) followed by the thoracic-descending region (+0.7 m/s, p < 0.001), the mid-descending region (+0.6 m/s, p < 0.001) and aortic arch (+0.4 m/s, p < 0.001). The average systolic diameters decreased moving distally (L1-5: 3.1 ± 0.4 cm, 2.3 ± 0.3 cm, 2.1 ± 0.3 cm, 1.9 ± 0.2 cm, and 1.7 ± 0.2 cm, respectively). The greatest variation in systolic diameter as a function of age occurred in the ascending region (+0.96 mm/decade, p < 0.001). Values of aPWV measured across the entire aorta were strongly correlated with PWV-tonometry (R = 0.71, p < 0.001), although they were significantly lower (mean difference 1.7 ± 1.6 m/s, p < 0.001).

CONCLUSIONS

The greatest difference in aortic stiffness occurs in the abdominal region, whereas the greatest difference in diameter occurs in the ascending aorta, which may help offset an increase in wall stiffness.

Using magnetic resonance imaging measurements for the determination of local wave speed and arrival time of reflected waves in human ascending aorta

Wave speed is one of the key factors describing wave propagation in arteries [1]. Local wave speed is directly related to the arterial wall properties [2]. With aging, arterial wave speed increases due to the stiffening of arterial wall, and also related to arterial disease.

Aortic calcification is associated with aortic stiffness and isolated systolic hypertension in healthy individuals

Arterial stiffening is an independent predictor of mortality and underlies the development of isolated systolic hypertension (ISH). A number of factors regulate stiffness, but arterial calcification is also likely to be important. We tested the hypotheses that aortic calcification is associated with aortic stiffness in healthy individuals and that patients with ISH exhibit exaggerated aortic calcification compared with controls. A total of 193 healthy, medication-free subjects (mean age+/-SD: 66+/-8 years) were recruited from the community, together with 15 patients with resistant ISH. Aortic pulse wave velocity (PWV) was measured noninvasively, and aortic calcium content was quantified from high-resolution, thoraco-lumbar computed tomography images using a volume scoring method. In healthy volunteers, calcification was positively and significantly associated with aortic PWV (r=0.6; P<0.0001) but was not related to augmentation index or brachial PWV. Calcification was significantly higher in treatment-resistant and healthy subjects with ISH compared with controls (mean [interquartile range]: 1.92 [1.14 to 3.66], 0.84 [0.35 to 1.75], and 0.19 [0.1 to 0.78] cm3, respectively; P<0.0001 for both). In a multiple regression model, aortic calcium was independently associated with aortic PWV along with age, mean arterial pressure, heart rate, and estimated glomerular filtration rate (R(2)=0.51; P<0.0001). Only age, calcium phosphate product, and aortic PWV were independently associated with calcification. These data suggest that calcification may be important in the process of aortic stiffening and the development of ISH. Calcification may underlie treatment resistance in ISH, and anticalcification strategies may present a novel therapy.