The promoting physical activity in regional and remote cancer survivors (PPARCS) trial: Physical activity maintenance

INTRODUCTION

The study examined whether increased physical activity (PA) in nonmetropolitan cancer survivors was maintained 12 weeks following the PPARCS intervention.

METHODS

PA outcomes were assessed using an accelerometer at baseline, end of the intervention, and at 24 weeks. Linear mixed models were used to examine between-group changes in PA outcomes.

RESULTS

The increased moderate-to-vigorous PA (MVPA) following intervention was maintained with significantly higher MVPA in the intervention group at 24 weeks (vs. controls) compared to baseline nett change of 52.5 min/week (95% CI 11.0-94.0.4).

CONCLUSIONS

Distance-based interventions using wearables and health coaching may produce MVPA maintenance amongst nonmetropolitan cancer survivors.

A randomized controlled trial of Promoting Physical Activity in Regional and Remote Cancer Survivors (PPARCS)

BACKGROUND

Physical activity (PA) is important for cancer survivors. Trials of remotely delivered interventions are needed to assist in reaching under-served non-metropolitan cancer survivors. The objective of this study was to ascertain whether wearable technology, coupled with health coaching was effective in increasing PA in breast and colorectal cancer survivors living in regional and remote areas in Australia.

METHODS

Cancer survivors from 5 states were randomized to intervention and control arms. Intervention participants were given a Fitbit Charge 2TM and received up to 6 telephone health coaching sessions. Control participants received PA print materials. Accelerometer assessments at baseline and 12 weeks measured moderate-to-vigorous PA (MVPA), light PA, and sedentary behavior.

RESULTS

Eighty-seven participants were recruited (age = 63 ± 11 years; 74 (85%) female). There was a significant net improvement in MVPA of 49.8 min/week, favoring the intervention group (95% confidence interval (95%CI): 13.6-86.1, p = 0.007). There was also a net increase in MVPA bouts of 39.5 min/week (95%CI: 11.9-67.1, p = 0.005), favoring the intervention group. Both groups improved light PA and sedentary behavior, but there were no between-group differences.

CONCLUSION

This is the first study to demonstrate that, when compared to standard practice (i.e., PA education), a wearable technology intervention coupled with distance-based health coaching, improves MVPA in non-metropolitan cancer survivors. The results display promise for the use of scalable interventions using smart wearable technology in conjunction with phone-based health coaching to foster increased PA in geographically disadvantaged cancer survivors.

Psychological correlates of physical activity and exercise preferences in metropolitan and nonmetropolitan cancer survivors

OBJECTIVE

Interventions to increase physical activity (PA) in cancer survivors have often adopted a "one-size-fits-all" approach and may benefit from being tailored to psychological constructs associated with behavior. The study objective was to investigate the exercise preferences and psychological constructs related to PA among cancer survivors.

METHODS

Posttreatment colorectal, endometrial, and breast cancer survivors (n = 183) living in metropolitan and nonmetropolitan areas completed survey measures of PA, exercise preferences, attitudes, self-efficacy, perceived behavioral control (PBC), and intention toward PA.

RESULTS

A structural equation model with adequate fit and quality indices revealed that instrumental attitude and self-efficacy were related to PA intention. Intention was related to behavior and mediated the relationship between self-efficacy and behavior. Preferred exercise intensity was related to self-efficacy, PBC, attitudes, and intention, while preferred exercise company was related to self-efficacy and PBC. Participants preferred moderate-intensity PA (71%), specifically self-paced (52%) walking (65%) in an outdoor environment (58%).

CONCLUSIONS

Since instrumental attitude and self-efficacy were associated with PA, incorporating persuasive communications targeting attitudes in PA interventions may promote PA participation. As cancer survivors who prefer low-intensity exercise and exercising with others report lower self-efficacy and PBC, interventions targeting confidence and successful experience in this group may also be warranted.

"To be there for my family" and "Keep my independence": Metropolitan and Non-Metropolitan Cancer Survivors' Health Behaviour Motives

PURPOSE

Cancer survivors are at risk of comorbidities and mortality, and those living outside of metropolitan areas are particularly susceptible given poorer socioeconomic, health and support resources. As engagement in health behaviours is affected by participants' autonomous motives, investigation of the motives of cancer survivors in metropolitan and non-metropolitan areas could elucidate the values and reasons for practising health behaviours, allowing programs to be tailored to these motives.

METHODS

Metropolitan (n = 103) and non-metropolitan (n = 80) Australian cancer survivors completed a survey item by describing their motives for physical activity and healthy diet change. Inductive thematic analysis of responses was performed to establish themes across health behaviour motives.

RESULTS

Analyses revealed four themes: to be able to, longevity, psychological health and appearance. Survivors primarily referred to being able to enjoy family, leisure activities, travel and staying independent, with these motives often linked to longevity. Motives were similar across locations; however, those in non-metropolitan locations reported continuation of work and pain relief more frequently. Female survivors more often reported weight loss.

CONCLUSIONS

A predominant motive for health behaviour change in cancer survivors across geographical location was the ability to enjoy family and engage in leisure and work activities. Programs aiming to promote health behaviours in cancer survivors might consider framing interventions accordingly by emphasizing benefits of longevity and maintaining independence.

Prophylaxis against Staphylococcus epidermidis vascular graft infection with rifampicin-soaked, gelatin-sealed Dacron

An animal model was used to assess the efficacy of rifampicin-impregnated, gelatin-sealed Dacron in the prevention of vascular graft infections caused by Staphylococcus epidermidis. Under a general anaesthetic an interposition graft was placed into sheep carotid artery. On completion of the operation 1 ml of normal saline containing 10(8) colony forming units (cfu) of a slime-producing S. epidermidis was inoculated directly onto the graft. After 3 weeks the graft was harvested. Swabs were taken of perigraft tissues, and of external and internal aspects of the graft. A 3-5-mm segment of the graft was incubated in broth medium and a second segment was ground for 5 min and incubated in broth medium. The presence of abscess formation and anastomotic disruption was assessed. Ten sheep received a gelatin-sealed Dacron graft (control), while nine received the same graft impregnated with rifampicin at a concentration of 1.2 mg/ml (treated). Eight of 10 control grafts were infected, with 30 of 50 possible cultures positive, compared with four of nine treatment grafts infected (P = 0.13) and 13 of 45 cultures positive (P = 0.004). The control group had four abscesses and two anastomotic disruptions; the treatment group had no abscesses (P = 0.05) or anastomotic disruptions (P = 0.26). Other organisms were isolated from nine of the 12 infected grafts, most commonly Staphylococcus aureus. There was no development of resistance to rifampicin. Rifampicin-impregnated, gelatin-sealed Dacron is successful at reducing the incidence of S. epidermidis vascular graft infection.

Development of a Staphylococcus epidermidis vascular graft infection model in sheep

Staphylococcus epidermidis is an increasingly recognized causative organism of vascular graft infections. To increase our understanding of this problem we have tried to establish Staph. epidermidis vascular graft infection in sheep by direct inoculation. A 2 cm long, 5 mm diameter polytetrafluoroethylene (PTFE) or a gelatin sealed Dacron vascular graft was inserted into the left carotid artery. At the completion of the operation 1 mL of normal saline containing either 10(4), 10(6), or 10(8) colony forming units (cfu) of a slime producing Staph. epidermidis was inoculated directly onto the graft. After 3 weeks the grafts were harvested in a sterile fashion. Swabs were taken of the perigraft tissues and the external and internal aspects of the grafts; a 3-5 mm segment of the graft was incubated in broth medium and a second segment was ground for 5 min and then incubated in broth medium. Note was made of the presence of abscess formation, anastomotic failure or thrombosis. Thirteen sheep received a PTFE graft and 14 received a gelatin sealed Dacron graft. Three sheep died immediately postoperatively. The rate of infection was 40% at 10(4), 67% at 10(6) and 80% at 10(8) cfu Staph. epidermidis. In only four cases were all five cultures positive. In nine cases two or less cultures were positive, the majority of these being the broth cultures. Nine other organisms were isolated from nine mixed infections. Nine out of 13 PTFE and seven out of 11 Dacron grafts were infected.(ABSTRACT TRUNCATED AT 250 WORDS)

Assessment of abdominal aortic aneurysm with magnetic resonance imaging

Pre-operative imaging of abdominal aortic aneurysms (AAA) is important in determining suitability for operation and operative approach. Ultrasound imaging is an excellent screening modality but is relatively poor at identifying renal arteries and the extent of iliac involvement. Computed tomography scanning with intravenous contrast and arteriography are invasive modalities that are associated with a small risk. Magnetic resonance imaging (MRI) offers the potential of accurate anatomical definition without use of contrast agents and passage of an intra-arterial catheter. Eight patients who had their AAA evaluated with MRI are reported. All had renal arteries accurately defined, intra-aneurysmal thrombosis was well delineated, and iliac extension was correctly identified in four cases. The initial experience has been most encouraging and the authors consider that MRI may become the investigation of choice for pre-operative AAA assessment.

Rifampicin impregnated Dacron grafts: no development of rifampicin resistance in an animal model

AIM

Rifampicin impregnated Dacron grafts have been shown to be effective at preventing vascular graft infection in different animal models. The development of resistance to rifampicin would be a major drawback to the widespread use of such a graft. We aimed to determine how readily this would occur by using a sheep animal model.

METHODS

Under general anaesthetic a 2cm long, 5mm diameter Dacron interposition graft inpregnated with 1.2 mg/ml rifampicin was placed in the left carotid artery. An extreme challenge of methicillin resistant Staphylococcus aureus (MRSA) using an inoculum of 10(9) colony forming units was placed directly onto the graft. The grafts were harvested at 3 weeks and cultures of the graft and tissues were taken. The presence or absence of any abscess formation, anastomotic disruption and graft thrombosis was noted. Any positive growths were identified and if found to be the same as the inoculum, the bacteria were used as the inoculum for another sheep. This was repeated once more. Thus we started with three sheep initially and used a total of nine sheep.

RESULTS

There were no deaths. All grafts were infected with the same MRSA strain, confirmed on phage typing. There were three abscess and one anastomotic disruption. Seven of the grafts were occluded. The minimal inhibitory concentration (MIC) of the infecting inoculum and the bacteria retrieved were determined using the agar dilutional method. The MIC for the three initial inocula was < 0.007 mg/l. All subsequent strains isolated had an MIC of < 0.015 mg/l. This was a difference of one dilution and not significant.

CONCLUSION

There was no development of rifampicin resistance using this animal model.

Comparison of fluoropolymer passivated Dacron and polytetrafluoroethylene grafts in a sheep model

The search for an optimal prosthetic vascular graft suitable for small vessels continues. The aim of this study was to compare a fluoropolymer passivated Dacron graft with a standard polytetrafluoroethylene graft. A sheep animal model was used. Under general anaesthesia a 5-cm length of 5-mm diameter graft was interposed into the left carotid artery. After an interval of 1, 2 or 3 months the sheep were reanaesthetized and a carotid angiogram performed before harvesting the graft. Graft patency was assessed by macroscopic inspection, angiography and histological examination. Overall, four of eight polytetrafluoroethylene grafts and three of ten fluoropolymer passivated Dacron grafts remained patent with similar patency rates at 1, 2 and 3 months. Histological examination of all available grafts showed evidence of fibrointimal hyperplasia. All but one of the occluded grafts had fibrointimal hyperplasia.