Engineering the fitness of older patients for chemotherapy : an exploration of Comprehensive Geriatric Assessment in practice

Clinicians often report that currently available methods to assess older patients, including standard clinical consultations, do not elicit the information necessary to make an appropriate cancer treatment recommendation for older cancer patients. An increasingly popular way of assessing the potential of older patients to cope with chemotherapy is a Comprehensive Geriatric Assessment. What constitutes Comprehensive Geriatric Assessment, however, is open to interpretation and varies from one setting to another. Furthermore, Comprehensive Geriatric Assessment’s usefulness as a predictor of fitness for chemotherapy and as a determinant of actual treatment is not well understood. In this article, we analyse how Comprehensive Geriatric Assessment was developed for use in a large cancer service in an Australian capital city. Drawing upon Actor–Network Theory, our findings reveal how, during its development, Comprehensive Geriatric Assessment was made both a tool and a science. Furthermore, we briefly explore the tensions that we experienced as scholars who analyse medico-scientific practices and as practitioner–designers charged with improving the very tools we critique. Our study contributes towards geriatric oncology by scrutinising the medicalisation of ageing, unravelling the practices of standardisation and illuminating the multiplicity of ‘fitness for chemotherapy’.

Predicting fitness for chemotherapy in older cancer patients

Background: The Vulnerable Elders Survey-13 (VES-13) is increasingly used to screen for older patients who can proceed to intensive chemotherapy without further comprehensive assessment. This study compared the VES-13 determination of fitness for treatment with the oncologist's assessments of fitness. Method: Sample: Consecutive series of solid tumour patients ≥65 years (n=175; M=72; range=65-86) from an Australian cancer centre. Patients were screened with the VES-13 before proceeding to usual treatment. Blinded to screening, oncologists concurrently predicted patient fitness for chemotherapy. A sample of 175 can detect, with 90% power, kappa coefficients of agreement between VES-13 and oncologists’ assessments >0.90 ("almost perfect agreement"). Separate backward stepwise logistic regression analyses assessed potential predictors of VES-13 and oncologists’ ratings of fitness. Results: Kappa coefficient for agreement between VES-13 and oncologists’ ratings of fitness was 0.41 (p<0.001). VES-13 and oncologists’ assessments agreed in 71% of ratings. VES-13 sensitivity = 83.3%; specificity = 57%; positive predictive value = 69%; negative predictive value = 75%. Logistic regression modelling indicated that the odds of being vulnerable to chemotherapy (VES-13) increased with increasing depression (OR=1.42; 95% CI: 1.18, 1.71) and decreased with increased functional independence assessed on the Bartel Index (OR=0.82; CI: 0.74, 0.92) and Lawton instrumental activities of daily living (OR=0.44; CI: 0.30, 0.65); RSquare=.65. Similarly, the odds of a patient being vulnerable to chemotherapy, when assessed by physicians, increased with increasing age (OR=1.15; CI: 1.07, 1.23) and depression (OR=1.23; CI: 1.06, 1.43), and decreased with increasing functional independence (OR=0.91; CI: 0.85, 0.98); RSquare=.32. Conclusions: Our data indicate moderate agreement between VES-13 and clinician assessments of patients’ fitness for chemotherapy. Current ‘one-step’ screening processes to determine fitness have limits. Nonetheless, screening tools do have the potential for modification and enhanced predictive properties in cancer care by adding relevant items, thus enabling fit patients to be immediately referred for chemotherapy.

Comprehensive assessment of the fitness of older people for chemotherapy

Purpose: To present the results of a mixed-method study comparing the level of agreement of a two-phased, nurse-administered Comprehensive Geriatric Assessment (CGA) with current methods that assess the fitness for chemotherapy of older cancer patients. A nurse-led model of multidisciplinary cancer care based on the results is also described. Methods: The two phases comprised initial screening by a nurse with the Vulnerable Elders Survey-13 [VES-13], followed by nurse administration of a detailed CGA. Both phases were linked to a computerised algorithm categorising the patient as ‘fit’, ‘vulnerable’ or ‘frail’. The study determined the level of agreement between VES-13- and CGA-determined categories; and between the CGA and the physicians’ assessments. It also compared the CGA’s predictive abilities in terms of subsequent treatment toxicity; while interviews determined the acceptability of the nurse-led procedure from key stakeholders' perspectives. Results: Data collection was completed in December 2011. The results will be presented at the conference. A consecutive-series n=170 will be enrolled, 33% of whom are ‘fit’; 33% ‘vulnerable’; and 33% ‘too frail’ for treatment. This sample can detect, with 90% power, kappa coefficients of agreement of ≥ 0.70 or higher (“substantial agreement”). Fitness sub-group comparisons of agreement between the medical oncologist and the nurse assessments can detect kappa estimates of Κ ≥ 0.80 with the same power. Conclusion: The results have informed a nurse-led model of cancer care. It meets a clear need to develop, implement and test a nurse-led, robust, evidence-based, clinically-justifiable and economically-feasible CGA process that has relevance in national and international contexts.

Outdoor flight testing of a pole inspection UAV incorporating high-speed vision

We present a pole inspection system for outdoor environments comprising a high-speed camera on a vertical take-off and landing (VTOL) aerial platform. The pole inspection task requires a vehicle to fly close to a structure while maintaining a fixed stand-off distance from it. Typical GPS errors make GPS-based navigation unsuitable for this task however. When flying outdoors a vehicle is also affected by aerodynamics disturbances such as wind gusts, so the onboard controller must be robust to these disturbances in order to maintain the stand-off distance. Two problems must therefor be addressed: fast and accurate state estimation without GPS, and the design of a robust controller. We resolve these problems by a) performing visual + inertial relative state estimation and b) using a robust line tracker and a nested controller design. Our state estimation exploits high-speed camera images (100Hz) and 70Hz IMU data fused in an Extended Kalman Filter (EKF). We demonstrate results from outdoor experiments for pole-relative hovering, and pole circumnavigation where the operator provides only yaw commands. Lastly, we show results for image-based 3D reconstruction and texture mapping of a pole to demonstrate the usefulness for inspection tasks.

Reliability and validity of physical fitness field tests for adults aged 55 to 70 years

The aim of this study was to examine the reliability and validity of field tests for assessing physical function in mid-aged and young-old people (55-70 y). Tests were selected that required minimal space and equipment and could be implemented in multiple field settings such as a general practitioner's office. Nineteen participants completed 2 field and I laboratory testing sessions. Intra-class correlations showed good reliability for the tests of upper body strength (lift and reach, R=.66), lower body strength (sit to stand, R=.80) and functional capacity (Canadian Step Test, R=.92), but not for leg power (single timed chair rise, R=.28). There was also good reliability for the balance test during 3 stances: parallel (94.7% agreement), semi-tandem (73.7%), and tandem (52.6%). Comparison of field test results with objective laboratory measures found good validity for the sit to stand (cf 1RM leg press, Pearson r=.68, p <.05), and for the step test (cf PWC140, r = -.60, p <.001), but not for the lift and reach (cf 1RM bench press, r=.43, p >.05), balance (r=-.13, -.18, .23) and rate of force development tests (r=-.28). It was concluded that the lower body strength and cardiovascular function tests were appropriate for use in field settings with mid-aged and young-old adults.

Tracking of physical activity, physical inactivity, and health-related physical fitness in rural youth

This study examined the tracking of selected measures of physical activity, inactivity, and fitness in a cohort of rural youth. Students (N = 181, 54.7% female, 63.5% African American) completed test batteries during their fifth-(age = 10.7 +/- 0.7 years), sixth-, and seventh-grade years. The Previous Day Physical Activity Recall (PDPAR) was used to assess 30-min blocks of vigorous physical activity (VPA), moderate-to-vigorous physical activity (MVPA), TV watching and other sedentary activities, and estimated energy expenditure (EE). Fitness measures included the PWC 170 cycle ergometer test, strength tests, triceps skinfold thickness, and BMI. Intraclass correlation coefficients (ICCs) for VPA, MVPA, and after-school EE ranged from 0.63 to 0.78. ICCs ranged from 0.49 to 0.71 for measures of inactivity and from 0.78 to 0.82 for the fitness measures. These results indicate that measures of physical activity, inactivity, and physical fitness tend to track during the transition from elementary to middle school.

Physical activity and physical fitness in African-American girls with and without obesity

Lack of physical activity and low levels of physical fitness are thought to be contributing factors to the high prevalence of obesity in African-American girls, To examine this hypothesis, we compared habitual physical activity and physical fitness in 54 African-American girls with obesity and 96 African-American girls without obesity residing in rural South Carolina, Participation in vigorous (greater than or equal to 6 METs) (VPA) or moderate and vigorous physical activity (greater than or equal to 4 METs) (MVPA) was assessed on three consecutive days using the Previous Day Physical Activity Recall, Cardiorespiratory fitness was assessed using the PWC 170 cycle ergometer test, Upper body strength was determined at two sites via isometric cable tensiometer tests, Relative to their counterparts without obesity, girls with obesity reported significantly fewer 30-minute blocks of VPA (0.90 +/- 0.14 vs. 1.3 +/- 0.14) and MVPA (1.2 +/- 0.18 vs. 1.7 +/- 0.16) (p<0.01), Within the entire sample, VPA and MVPA were inversely associated with body mass index (r=-0.17 and r=-0.19) and triceps skinfold thickness (r=-0.19 and r=-0.22) (p<0.05), In the PWC 170 test and isometric strength tests, girls with obesity demonstrated absolute scores that were similar to, or greater than, those of girls without obesity; however, when scores were expressed relative to bodyweight, girls with obesity demonstrated significantly lower values (p<0.05). The results support the hypothesis that lack of physical activity and low physical fitness are important contributing factors in the development and/or maintenance of obesity in African-American girls.

Close-quarters Quadrotor flying for a pole inspection with position based visual servoing and high-speed vision

This paper presents a 100 Hz monocular position based visual servoing system to control a quadrotor flying in close proximity to vertical structures approximating a narrow, locally linear shape. Assuming the object boundaries are represented by parallel vertical lines in the image, detection and tracking is achieved using Plücker line representation and a line tracker. The visual information is fused with IMU data in an EKF framework to provide fast and accurate state estimation. A nested control design provides position and velocity control with respect to the object. Our approach is aimed at high performance on-board control for applications allowing only small error margins and without a motion capture system, as required for real world infrastructure inspection. Simulated and ground-truthed experimental results are presented.

Distribution of fitness in populations of dengue viruses

Genetically diverse RNA viruses like dengue viruses (DENVs)segregate into multiple, genetically distinct, lineages that temporally arise and disappear on a regular basis. Lineage turnover may occur through multiple processes such as, stochastic or due to variations in fitness. To determine the variation of fitness, we measured the distribution of fitness within DENV populations and correlated it with lineage extinction and replacement. The fitness of most members within a population proved lower than the aggregate fitness of populations from which they were drawn, but lineage replacement events were not associated with changes in the distribution of fitness. These data provide insights into variations in fitness of DENV populations, extending our understanding of the complexity between members of individual populations.

Inspection of pole-like structures using a vision-controlled VTOL UAV and shared autonomy

We present an approach for the inspection of vertical pole-like infrastructure using a vertical take-off and landing (VTOL) unmanned aerial vehicle and shared autonomy. Inspecting vertical structures, such as light and power distribution poles, is a time consuming, dangerous and expensive task with high operator workload. To address these issues, we propose a VTOL platform that can operate at close-quarters, whilst maintaining a safe stand-off distance and rejecting environmental disturbances. We adopt an Image based Visual Servoing (IBVS) technique using only two line features to stabilise the vehicle with respect to a pole. Visual, inertial and sonar data are used, making the approach suitable for indoor or GPS-denied environments. Results from simulation and outdoor flight experiments demonstrate the system is able to successfully inspect and circumnavigate a pole.

Improving muscular endurance with the MVe Fitness ChairTM in breast cancer survivors: A feasibility and efficacy study

Objectives To assess the feasibility and efficacy of delivering Pilates exercises for resistance training to breast cancer survivors using the MVe Fitness Chair™. Design Pilot randomized controlled trial. Methods Twenty-six female breast cancer survivors were randomized to use the MVe Fitness Chair™ (n = 8), traditional resistance training (n = 8), or a control group (no exercise) (CO) (n = 10). The MVe Fitness Chair™ and traditional resistance training groups completed 8 weeks of exercise. Muscular endurance was assessed pre and post-test for comparisons within and between groups using push ups, curl ups, and the Dynamic Muscular Endurance Test Battery for Cancer Patients of Various Ages. Results Feasibility of the MVe Fitness Chair™ was good, evidenced by over 80% adherence for both exercise groups and positive narrative feedback. Significant improvements in muscular endurance were observed in the MVe Fitness Chair™ (p < 0.002) and traditional resistance training groups (p < 0.001), but there were no differences in improvement between the MVe Fitness Chair™ and traditional resistance training groups (p < 0.711) indicating that Pilates and traditional resistance training may be equally effective at improving muscular endurance in this population. Conclusions The MVe Fitness Chair™ is feasible for use in breast cancer survivors. It appears to promote similar improvements in muscular endurance when compared to traditional resistance training, but has several advantages over traditional resistance training, including cost, logistics, enjoyment, and ease of learning.

A Note on the Genericity of Simultaneous Stabilizability and Pole Assignability

n this paper we study the genericity of simultaneous stabilizability, simultaneous strong stabilizability, and simultaneous pole assignability, in linear multivariable systems. The main results of the paper had been previously established by Ghosh and Byrnes using state-space methods. In contrast, the proofs in the present paper are based on input-output arguments, and are much simpler to follow, especially in the case of simultaneous and simultaneous strong stabilizability. Moreover, the input-output methods used here suggest computationally reliable algorithms for solving these two types of problems. In addition to the main results, we also prove some lemmas on generic greatest common divisors which are of independent interest.

Pole placement in multi-input systems via elementary transformations

This paper is concerned with the development of an algorithm for pole placement in multi-input dynamic systems. The algorithm which uses a series of elementary transformations is believed to be simpler, computationally more efficient and numerically stable when compared with earlier methods. In this paper two methods have been presented.

Influence of food supplementation on the fitness of two biological control agents: a predatory nabid bug and a bollworm pupal parasitoid

Many arthropod predators and parasitoids exhibit either stage-specific or lifetime omnivory, in that they include extra-floral nectar, floral nectar, honeydew or pollen in their immature and/or adult diet. Access to these plant-derived foods can enhance pest suppression by increasing both the individual fitness and local density of natural enemies. Commercial products such as Amino-Feed®, Envirofeast®, and Pred-Feed® can be applied to crops to act as artificial-plant-derived foods. In laboratory and glasshouse experiments we examined the influence of carbohydrate and protein rich Amino-Feed UV® or Amino-Feed, respectively, on the fitness of a predatory nabid bug Nabis kinbergii Reuter (Hemiptera: Nabidae) and bollworm pupal parasitoid Ichneumon promissorius (Erichson) (Hymenoptera: Ichneumonidae). Under the chosen conditions, the provision of either wet or dry residues of Amino-Feed UV had no discernable effect on immediate or longer-term survival and immature development times of N. kinbergii. In contrast, the provision of honey, Amino-Feed plus extrafloral nectar, and extrafloral nectar alone had a marked effect on the longevity of I. promissorius, indicating that they were limited by at least carbohydrates as an energy source, but probably not protein. Compared with a water only diet, the provision of Amino-Feed plus extrafloral nectar increased the longevity of males and females of I. promissorius by 3.0- and 2.4-fold, respectively. Not only did female parasitoids live longer when provided food, but the total number of eggs laid and timing of deposition was affected by diet under the chosen conditions. Notably, females in the water and honey treatments deposited greater numbers of eggs earlier in the trial, but this trend was unable to be sustained over their lifetime. Egg numbers in these treatments subsequently fell below the levels achieved by females in the Amino-Feed plus extrafloral nectar and cotton extrafloral nectar only treatments. Furthermore, there were times when the inclusion of the Amino-Feed was beneficial compared with cotton extrafloral nectar only. Artificial food supplements and plant-derived foods are worthy of further investigation because they have potential to improve the ecosystem service of biological pest control in targeted agroecosystems by providing natural enemies with an alternative source of nutrition, particularly during periods of prey/host scarcity.