Who moves in vulnerable Caribbean neighborhoods? Positive deviance for physical activity: Findings from the Jamaica health and Lifestyle Survey 2017 (JHLS III)

Decreased physical activity (PA) has been associated with residents living in neighborhoods perceived as being disordered or having high crime levels. What is unknown are the characteristics of individuals who engage in moderate to vigorous levels of PA (MVPA) despite living in these vulnerable neighborhoods, or who may be referred to as positive deviants (PD). We examined the factors associated with PD for PA among Jamaicans. Between 2016 and 2017 the Jamaica Health and Lifestyle Survey, a cross-sectional nationally representative survey (n = 2807), was conducted on individuals aged 15 years and older. Regression analyses were performed to identify associations with PD, defined using engagement in MVPA among persons living in vulnerable neighborhoods (N = 1710). Being female (odds ratio [OR]a = 0.64 (0.48, 0.86); p = 0.003), obese while living in an urban area (ORa = 0.39; 95 % CI = 0.26, 0.59; p < 0.0001), unemployed (ORa = 0.53; 95 % CI = 0.39, 0.73; p < 0.0001), or a student (ORa = 0.62; 95 % CI = 0.39, 0.98); p = 0.041) was associated with a significantly lower likelihood of PD, while having a personal medical history of at least one chronic disease significantly increased likelihood (ORa = 1.43; 95 % CI = 1.08, 1.90; p = 0.014). Taking a PD approach may be one angle to consider in trying to determine what is working and for whom, so that this may be harnessed in policy, prevention and intervention programming to increase PA.

Robust deep learning-based protein sequence design using ProteinMPNN

Although deep learning has revolutionized protein structure prediction, almost all experimentally characterized de novo protein designs have been generated using physically based approaches such as Rosetta. Here, we describe a deep learning-based protein sequence design method, ProteinMPNN, that has outstanding performance in both in silico and experimental tests. On native protein backbones, ProteinMPNN has a sequence recovery of 52.4% compared with 32.9% for Rosetta. The amino acid sequence at different positions can be coupled between single or multiple chains, enabling application to a wide range of current protein design challenges. We demonstrate the broad utility and high accuracy of ProteinMPNN using x-ray crystallography, cryo-electron microscopy, and functional studies by rescuing previously failed designs, which were made using Rosetta or AlphaFold, of protein monomers, cyclic homo-oligomers, tetrahedral nanoparticles, and target-binding proteins.

Triazole-derivatized near-infrared cyanine dyes enable local functional fluorescent imaging of ocular inflammation

Near-infrared (NIR) chemical fluorophores are promising tools for in-vivo imaging in real time but often succumb to rapid photodegradation. Indocyanine green (ICG) is the only NIR dye with regulatory approval for ocular imaging in humans; however, ICG, when employed for applications such as labelling immune cells, has limited sensitivity and does not allow precise detection of specific inflammatory events, for example leukocyte recruitment during uveitic flare-ups. We investigated the potential use of photostable novel triazole NIR cyanine (TNC) dyes for detecting and characterising activated T-cell activity within the eye. Three TNC dyes were evaluated for ocular cytotoxicity in-vitro using a MTT assay and optimised concentrations for intraocular detection within ex-vivo porcine eyes after topical application or intracameral injections of the dyes. TNC labelled T-cell tracking experiments and mechanistic studies were also performed in-vitro. TNC-1 and TNC-2 dyes exhibited greater fluorescence intensity than ICG at 10 μM, whereas TNC-3 was only detectable at 100 μM within the porcine eye. TNC dyes did not demonstrate any ocular cell toxicity at working concentrations of 10 μM. CD4⁺T-cells labelled with TNC-1 or TNC-2 were detected within the porcine eye, with TNC-1 being brighter than TNC-2. Detection of TNC-1 and TNC-2 into CD4⁺T-cells was prevented by prior incubation with dynole 34-2 (50 μM), suggesting active uptake of these dyes via dynamin-dependent processes. The present study provides evidence that TNC dyes are suitable to detect activated CD4⁺T-cells within the eye with potential as a diagnostic marker for ocular inflammatory diseases.

Cost-effectiveness analysis of a model of first-trimester prediction and prevention of preterm pre-eclampsia compared with usual care

OBJECTIVES

Pre-eclampsia (PE) causes substantial maternal and neonatal mortality and morbidity. In addition to the personal impact on women, children and their families, PE has a significant economic impact on our society. Recent research suggests that a first-trimester multivariate model is highly predictive of preterm (< 37 weeks' gestation) PE and can be combined successfully with targeted prophylaxis (low-dose aspirin), resulting in an 80% reduction in prevalence of disease. The aim of this study was to examine the potential health outcomes and cost implications following introduction of first-trimester prediction and prevention of preterm PE within a public healthcare setting, compared with usual care, and to conduct a cost-effectiveness analysis to inform health-service decisions regarding implementation of such a program.

METHODS

A decision-analytic model was used to compare usual care with the proposed first-trimester screening intervention within the obstetric population (n = 6822) attending two public hospitals within a metropolitan district health service in New South Wales, Australia, between January 2015 and December 2016. The model, applied from early pregnancy, included exposure to a variety of healthcare professionals and addressed type of risk assessment (usual care or first-trimester screening) and use of (compliance with) low-dose aspirin prescribed prophylactically for prevention of PE. All pathways culminated in six possible health outcomes, ranging from no PE to maternal death. Results were presented as the number of cases of PE gained/avoided and the incremental increase/decrease in economic costs arising from the intervention compared with usual care. Significant assumptions were tested in sensitivity/uncertainty analyses.

RESULTS

The intervention produced, across all gestational ages, 31 fewer cases of PE and reduced aggregate economic health-service costs by 1 431 186 Australian dollars over the 2-year period. None of the tested iterations of uncertainty analyses reported additional cases of PE or higher economic costs. The new intervention based on first-trimester screening dominated usual care.

CONCLUSION

This cost-effectiveness analysis demonstrated a reduction in prevalence of preterm PE and substantial cost savings associated with a population-based program of first-trimester prediction and prevention of PE, and supports implementation of such a policy. © 2020 International Society of Ultrasound in Obstetrics and Gynecology.

A mixed-methods evaluation of the impact of a pharmacist-led feedback pilot intervention on insulin prescribing in a hospital setting

AIMS

To explore the impact of a prescribing feedback intervention on insulin prescribing.

METHODS

This was a mixed-methods study in a hospital setting. An insulin prescribing feedback intervention was delivered verbally and in writing to twelve doctors. Insulin prescribing error frequency was compared to ten doctors who had not received the feedback intervention. Insulin prescribing was audited over four weeks at the start and end of the intervention period. Semi-structured interviews were conducted with participating doctors who had received feedback, and qualitative data analysed thematically to explore the impact of the intervention on their prescribing practice.

RESULTS

Prescribing data were collected on 370 insulin prescriptions with 241 errors identified. A significant reduction (χ2 = 22.6, p=<0.05) in insulin prescribing error frequency was observed in the intervention group, with a non-significant increase reported in the control group. Feedback was received positively and considered valuable by doctors, supporting development of their knowledge and skills and encouraging reflection on their prescribing performance. Doctors described enhanced confidence in insulin prescribing and a desire to improve as a prescriber and avoid harm, with feedback raising awareness of their development needs. Prescribers also described enhanced team work, with greater information and feedback seeking behavior to inform future prescribing decisions.

CONCLUSIONS

Feedback has potential to improve insulin prescribing and is a valued and acceptable process intervention for doctors. The impact on insulin prescribing practice is varied and complex influencing the capability, opportunity and motivation of prescribers to adapt and evolve their behavior in response to ongoing feedback.

P6341Impact of left-ventricular hemodynamics on treadmill exercise intolerance in conscious rats: pilot evaluation in animals with diastolic dysfunction

Introduction

Exercise intolerance is a clinical hallmark of patients with hypertrophic cardiomyopathy and/or impaired diastolic function. Elevated LV filling pressures, particularly in response to acute exercise bouts, are thought to play a role limiting exercise capacity in ventricles with abnormal relaxation/compliance. However, it is experimentally difficult to obtain in vivo hemodynamic measures necessary for the evaluation of centrally mediated dysfunction. Leveraging radio-telemetry, we evaluated central hemodynamic parameters as mediators of exercise intolerance in obese ZSF1 rats with diabetes, hypertension, and diastolic dysfunction.

Methods

Both ZSF1 (637+12g, n=8) and age-matched (28 weeks) healthy control (CTRL, 543+14g, n=4, P<0.05) rats were instrumented for telemetric left-ventricular pressure (LVP) recordings. Following surgical recovery rats were familiarized to treadmill running and subsequently challenged with an exercise protocol aimed at increasing heart rate by 200 beats/min (5° incline, 15 m/min, increased by 3 m/min every 2-min) until volitional exhaustion. LV pressures were collected continuously during cage resting, treadmill resting, and post-exercise until heart rate returned to baseline. Additionally, resting echocardiographic and blood glucose measures were collected.

Results

At rest, ZSF1 rats had preserved ejection fraction (73+6 vs 79+9%), elevated (P<0.05) blood glucose (237+83 vs 94+23 mg/dL), end-systolic (147+18 vs 103+13 mmHg), and end-diastolic pressures (16+3 vs 9+3 mmHg), with preserved indexed end-diastolic volumes (670+95 vs 741+89 μL/kg), suggesting impaired diastolic compliance. ZSF1 rats terminated exercise prematurely (8:26+1:20 vs 10:27+1:18 min, P<0.05), indicating a limitation in exercise capacity. This early volitional exhaustion was noted while end-diastolic pressures were not further increased (17+7 mmHg), suggesting that other pathological derangement may play a role modulating exercise capacity. For instance, ZSF1 rats tended to have a blunted increase in the systolic index dP/dt40 (+2589+1450 vs +3938+749 mmHg/s, P<0.1) despite achieving comparable increases in HR (193+34 vs 196+38 bpm) with exercise.

Conclusion

This pilot study demonstrates the feasibility for evaluation of left-ventricular hemodynamics during exercise in rodents with diastolic dysfunction, establishing a platform to evaluate both the mechanisms of exercise intolerance as well as potential therapeutic approaches to rescue exercise capacity.

Acknowledgement/Funding

MyoKardia

Passive-dynamic ankle-foot orthosis improves medium-term clinical outcomes after severe lower extremity trauma

Introduction

Individuals with delayed below-knee amputation have previously reported superior clinical outcomes compared with lower limb reconstruction. The UK military have since introduced a passive-dynamic ankle-foot orthosis (PDAFO) into its rehabilitation care pathway to improve limb salvage outcomes. The aims were to determine if wearing a PDAFO improves medium-term clinical outcomes and what influence does multidisciplinary team (MDT) rehabilitation have after PDAFO fitting? Also, what longitudinal changes in clinical outcomes occur with MDT rehabilitation and how do these results compare with patients with previous lower extremity trauma discharged prior to PDAFO availability?

Methods

We retrospectively evaluated levels of mobility, activities of daily living, anxiety, depression and pain in a heterogeneous group of 23 injured UK servicemen 34±11 months after PDAFO provision. We also retrospectively analysed 16 patients across four time points (pre-PDAFO provision, first, second and final inpatient admissions post-PDAFO provision) using identical outcome measures, plus the 6 min walk test.

Results

Outcomes were compared with previous below-knee limb salvage and amputees. Before PDAFO, 74% were able to walk and 4% were able to run independently. At follow-up, this increased to 91% and 57%, respectively. Mean depression and anxiety scores remained stable over time (p>0.05). After 3 weeks, all patients could walk independently (pre-PDAFO=31%). Mean 6 min walk distance significantly increased from 440±75 m (pre-PDAFO) to 533±68 m at last admission (p=0.003). The ability to run increased from 6% to 44% after one admission.

Conclusions

All functional and most psychosocial outcomes in PDAFO users were superior to previous limb salvage and comparable to previous below-knee amputees. The PDAFO facilitated favourable short-term and medium-term changes in all clinical outcome measurements.

Development and evaluation of a website for surveillance of healthcare-associated urinary tract infections in Australia

Phase II of the Surveillance to Reduce Urinary Tract Infections project piloted a website for point prevalence surveys of healthcare-associated (HAUTI) and catheter-associated urinary tract infection in Australian hospitals and aged care homes. This report describes development and evaluation of the website for online data collection. Evaluation findings from 38 data collectors indicated that most respondents found website registration and web form use easy (N = 22; 58% and N = 16; 43%, respectively). The need for improved computer literacy skills and automated data systems were highlighted. This study demonstrated a novel approach for Australian HAUTI data collection; however, refinements are needed before national roll-out.

Survey of infection control and antimicrobial stewardship practices in Australian residential aged-care facilities

This study assessed infection prevention and antimicrobial stewardship (AMS) practices in Australian residential aged-care facilities (RACF). Two hundred and sixty-five surveys (15.6%) were completed with all states represented and the majority (177 (67.3%)) privately run. Only 30.6% RACF had infection control trained staff on site. Few facilities had AMS policies, only 14% had antimicrobial prescribing restrictions. Most facilities offered vaccination to residents (influenza vaccination rates >75% in 73% of facilities), but pneumococcal vaccination was poor.

A modern-day solution to a 100-yearold problem: the use of a bespoke offloading brace in the rehabilitation of ‘Deck-Slap’ and other high-energy lower limb injuries

‘Deck-Slap’ is an injury pattern first described at the Battle of Jutland; it is still relevant today, with anti-vehicle mines a significant threat to Coalition troops. The effect of a device exploding beneath a vehicle produces a wave of high energy that is rapidly transmitted through the steel floor; this causes significant axial loading of lower limbs often resulting in severe fractures (notably of the calcaneum). Recent advancements in orthopaedic surgery have allowed for limbs that were destined for immediate amputation following significant trauma to be salvaged. However, despite intense rehabilitation, many of these salvaged limbs have subsequently gone on to delayed amputation, as functional outcomes are often poor. Technologically advanced prosthetic devices are available that afford good quality of life and allow for increased activity levels; these devices are, however, expensive to procure and maintain. This report describes a United Kingdom (UK) Armed Forces soldier who suffered a typical ‘deck-slap’ injury in Afghanistan with subsequent limb salvage. The use of the Bespoke Off-loading Brace (BOB) is discussed. The results presented here indicate that the biomechanical function of a patient with this type of injury improves when wearing the BOB. Further studies are needed to assess long-term clinical outcomes and the functional benefit of the device as a viable and cost-effective alternative to delayed limb amputation.

A modern-day solution to a 100-year-old problem: the use of a Bespoke Off-loading Brace in the rehabilitation of 'Deck-Slap' and other high-energy lower limb injuries

'Deck-Slap' is an injury pattern first described at the Battle of Jutland; it is still relevant today, with anti-vehicle mines a significant threat to Coalition troops. The effect of a device exploding beneath a vehicle produces a wave of high energy that is rapidly transmitted through the steel floor; this causes significant axial loading of lower limbs often resulting in severe fractures (notably of the calcaneum). Recent advancements in orthopaedic surgery have allowed for limbs that were destined for immediate amputation following significant trauma to be salvaged. However, despite intense rehabilitation, many of these salvaged limbs have subsequently gone on to delayed amputation, as functional outcomes are often poor. Technologically advanced prosthetic devices are available that afford good quality of life and allow for increased activity levels; these devices are, however, expensive to procure and maintain. This report describes a United Kingdom (UK) Armed Forces soldier who suffered a typical 'deck-slap' injury in Afghanistan with subsequent limb salvage. The use of the Bespoke Off-loading Brace (BOB) is discussed. The results presented here indicate that the biomechanical function of a patient with this type of injury improves when wearing the BOB. Further studies are needed to assess long-term clinical outcomes and the functional benefit of the device as a viable and cost-effective alternative to delayed limb amputation.

Cardiac autonomic function and baroreflex changes following 4 weeks of resistance versus aerobic training in individuals with pre-hypertension

AIM

Cardiac autonomic modulation and baroreflex sensitivity (BRS) are altered in individuals with hypertension. Aerobic exercise (AE) training has been shown to improve both measures, yet little is known about the effects of resistance exercise (RE). The purpose of this study was to examine the heart rate variability (HRV) and BRS following 4 weeks of resistance or aerobic training in a population with borderline high blood pressure (BP).

METHODS

Twenty-nine mild hypertensives were recruited and randomly assigned to 4 weeks of RE or AE training. Before and after training, resting measures of HRV frequencies and BRS were obtained.

RESULTS

There was a significant decrease in resting systolic BP for both exercise training modes (RE 136 +/- 3.0 pre- to 132 +/- 3.4 post-training vs. AE 142 +/- 4.0 pre- to 137 +/- 3.6 mmHg post-training, P = 0.019). Diastolic BP decreased significantly following both exercise training modes (RE 78 +/- 1.31 pre to 74 +/- 1.1 post vs. AE 80 +/- 1.7 pre to 77 +/- 1.6 mmHg post, P = 0.002). A significant time by training mode interaction for low frequency : high frequency (HF) ratio (P = 0.017) with AE decreasing the ratio (275.21 +/- 67.28 to 161.26 +/- 61.49) and RE increasing this ratio (143.73 +/- 65.00 to 227.83 +/- 59.41). Natural log-transformed (ln) HRV values showed a time-by-training mode interaction for ln HF (P = 0.05) as ln HF increased (4.7 +/- 0.38 to 5.4 +/- 0.35 ms(2)) following AE and decreased (5.98 +/- 0.37 to 5.76 +/- 0.42 ms(2)) following RE. BRS increased following aerobic training and decreased after resistance training (6.74 +/- 1.2 to 7.94 +/- 1.3 and 10.44 +/- 1.2 to 9.1 +/- 1.2 ms mmHg(-1) respectively, P = 0.021).

CONCLUSIONS

Aerobic exercise improved the autonomic nervous system (increasing vagal tone, reducing sympathovagal balance while increasing BRS) while RE showed no improvements in cardiac autonomic tone and decreased BRS.

Gastric adenocarcinoma and chronic gastritis in two related Persian cats

Two 12.5-year-old castrated male Persian cats from the same household, whose dams were littermates, presented simultaneously with gastric adenocarcinoma associated with proliferative and fibrosing gastritis. Intralesional adult Ollulanus tricuspis nematodes and rare surface-associated spiral-shaped bacteria were identified in one cat. No etiologic agents were identified in tissues from the second cat; however, gastric mucosa was examined following anthelmintic treatment. Clinical signs in each cat had commenced 2 months apart and included vomiting, hematemesis, intermittent melena, and weight loss. This is the first report of gastric adenocarcinoma occurring in housemate cats or cats of common descent. Carcinogenesis may have been influenced by shared undetermined genetic and environmental factors, possibly including Ollulanus tricuspis, spiral-shaped bacteria, or other etiologies for chronic gastritis that remain unidentified.

To thin or not to thin: the use of the anterolateral thigh flap in the reconstruction of intraoral defects

The anterolateral thigh (ALT) flap has achieved popularity recently for free-flap reconstruction of intraoral defects following excision of squamous cell carcinoma. We have assessed the feasibility of the ALT flap as a free flap for oral lining and the potential use of the thinned ALT flap in a one-stage reconstruction. We used the ALT flap to reconstruct the oral cavity in 18 consecutive patients between December 2000 and December 2001 following intraoral resection of squamous cell carcinoma. Twelve patients underwent reconstruction using a standard ALT flap, four patients received a thinned ALT flap in a one-stage procedure, one patient received a standard ALT flap in combination with a fibula flap and one patient received a combination of a standard ALT flap and vascularised iliac bone. There were no complications in any of the 14 cases in which a standard ALT flap was used. Two of these flaps were thinned subsequently as secondary procedures. Of the four thinned ALT flaps, one flap failed completely and two flaps experienced partial necrosis. In all but one case the donor site was closed directly with minimal donor-site morbidity. The ALT flap is a versatile flap that can be used in combination with other flaps for more complex defects with minimal donor-site morbidity and is a useful alternative in the armamentarium of the head and neck surgeon. Thinning of the flap is best performed as a secondary procedure, should it be required.

Basis for intracellular retention of a human mutant of the retinal rod channel alpha subunit

A mutant of the a subunit of the retinal rod cyclic GMP-gated channel, [Arg654(1-bp del)], corresponding to a truncated alphaR654Dstop subunit, was previously described in patients with retinitis pigmentosa: when expressed in HEK-293 cells, this mutated a subunit was retained inside the cell, but had normal channel activity in one case where it reached the plasma membrane, indicating that the mechanism of targeting is altered by the mutation, but not the function of the channel. The corresponding mutants of the bovine rod channel (alphaR656D stop), and of the closely related olfactory neuron channel (alphaR632Dstop) alpha subunits were expressed in Xenopus oocytes and their activity was analyzed by patch-clamp. Like their human homologue, these two channels have no activity, and we show that their GFP fusion proteins are accumulated into intracellular compartments. The truncation alone or the R/D mutation alone do not prevent or modify channel activity, indicating that neither the R656 residue nor the C-terminal domain downstream of R656 is necessary for homomeric channel targeting and function. Several mutations of R656 and of the preceding residues in the R656Dstop mutant disclose that the motif responsible for the absence of channel activity is an endoplasmic reticulum retention signal (KXKXXstop) in which the nature of the residues in positions -1 and -4 is determinant.

Interaction of plant protein Ser/Thr phosphatase PP7 with calmodulin

We have recently identified PP7, a novel group of plant protein Ser/Thr phosphatases, and hypothesized that PP7 may possess a calmodulin-binding site. To test this hypothesis, we assessed the effect of calmodulin on the activity of recombinant Arabidopsis thaliana PP7 and directly tested interaction between PP7 and calmodulin using surface plasmon resonance. Calmodulin exerted a moderate inhibitory effect on the phosphatase activity of PP7 with submicromolar affinity. PP7 specifically interacted with immobilized calmodulin (but not with recoverin, another EF hand Ca(2+)-binding protein) in a strictly Ca(2+)-dependent manner with nanomolar affinity. Deletion of an insert in the catalytic domain of PP7, predicted to function as a calmodulin-binding site, greatly decreased PP7 binding to calmodulin. These findings provide the first evidence for a plant protein phosphatase directly interacting with calmodulin and indicate that PP7 might be regulated by Ca(2+) levels in vivo.

Preventing falls in older people: impact of an intervention to reduce environmental hazards in the home

OBJECTIVES

To evaluate the impact of an intervention to reduce fall hazards in the homes of older people.

DESIGN

The intervention was administered to the 570 subjects in the experimental arm of a randomized controlled trial, with follow-up of subjects for 1 year.

SETTING

Community-based seniors living in Perth, Australia.

PARTICIPANTS

People age 70 and older.

INTERVENTION

Registered nurses delivered the intervention. It consisted of a home hazard assessment, an educational strategy on general fall hazard reduction and ways to reduce identified home hazards, and the free installation of safety devices: grab rails, nonslip stripping on steps, and double-sided tape for floor rugs and mats. All intervention subjects received the home hazard assessment, and 96% received the educational strategy. Grab rails were installed in 77% of homes, rugs were stabilized in 8%, and nonslip step stripping was installed in 36%.

MEASUREMENTS

Hazard prevalence was assessed at baseline in all homes and 11 months later in a random sample of 51 homes. Action taken in response to the intervention was assessed by a self-completed postal questionnaire completed 11 months after the intervention.

RESULTS

All homes had at least one fall hazard. The most prevalent were floor rugs and mats (mean of 14 per home), stepovers (Stepovers are structural changes to the height of the floor that were designed to be stepped over rather than stepped upon, for example, the lip of a shower or a bath side.) (mean of seven per home), steps (mean of four per home), and trailing cords (mean of two per home). The intervention was associated with a small but significant reduction in four of the five most prevalent hazards. The mean number of unsafe rugs and mats was reduced by 1.57 per house (95% confidence interval (CI) = 0.91-2.24); the mean number of unsafe steps was reduced by 0.61 per house (95% CI = 0.28-0.94); the mean number of rooms with trailing cords was reduced by 0.43 per house (95% CI = 0.10-0.76); and the mean number of unsafe chairs was reduced by 0.10 per house (95% CI = 0.02-0.18). Safety devices were installed in 81.9% of homes. Advice on modifying specific hazards identified on the home hazard assessment resulted in over 50% of subjects removing hazards of floor rugs and mats, trailing cords, and obstacles. The general education message prompted less activity to reduce these hazards than did the advice on identified hazards.

CONCLUSIONS

Fall hazards are ubiquitous in the homes of older people. The intervention resulted in a small reduction in the mean number of hazards per house, with many study subjects taking action but removing only a few hazards. The impact of the intervention in achieving self-reported action to reduce hazards was high.

Preventing falls in older people: outcome evaluation of a randomized controlled trial

OBJECTIVES

To evaluate the outcome of an intervention to reduce hazards in the home on the rate of falls in seniors.

DESIGN

Randomized controlled trial, with follow-up of subjects for 1 year.

SETTING

Community-based study in Perth, Western Australia.

PARTICIPANTS

People age 70 and older.

INTERVENTION

One thousand eight hundred seventy-nine subjects were recruited and randomly allocated by household to the intervention and control groups in the ratio 1:2. Because of early withdrawals, 1,737 subjects commenced the study. All members of both groups received a single home visit from a research nurse. Intervention subjects (n = 570) were offered a home hazard assessment, information on hazard reduction, and the installation of safety devices, whereas control subjects (n = 1,167) received no safety devices or information on home hazard reduction.

MEASUREMENTS

Both groups recorded falls on a daily calendar. Reported falls were confirmed by a semistructured telephone interview and were assigned to one of three overlapping categories: all falls, falls inside the home, and falls involving environmental hazards in the home. Analysis was by multivariate modelling of rate ratios and odds ratios for falls, corrected for household clustering, using Poisson regression and logistic regression with robust variance estimation.

RESULTS

Overall, 86% of study subjects completed the 1 year of follow-up. The intervention was not associated with any significant reduction in falls or fall-related injuries. There was no significant reduction in the intervention group in the incidence rate of falls involving environmental hazards inside the home (adjusted rate ratio, 1.11; 95% CI = 0.82-1.50), or the proportion of the intervention group who fell because of hazards inside the home (adjusted odds ratio, 0.97; 95% CI = 0.74-1.28). No reduction was seen in the rate of all falls (adjusted rate ratio, 1.02; 95% CI = 0.83-1.27) or the rate of falls inside the home (adjusted rate ratio, 1.17; 95% CI = 0.85-1.60). There was no significant reduction in the rate of injurious falls in intervention subjects (adjusted rate ratio, 0.92; 95% CI = 0.73-1.14).

CONCLUSIONS

The intervention failed to achieve a reduction in the occurrence of falls. This was most likely because the intervention strategies had a limited effect on the number of hazards in the homes of intervention subjects. The study provides evidence that a one-time intervention program of education, hazard assessment, and home modification to reduce fall hazards in the homes of healthy older people is not an effective strategy for the prevention of falls in seniors.

A paired comparison of tuberculin skin test results in health care workers using 5 TU and 10 TU tuberculin

BACKGROUND

Historically, 10 TU has been employed in Australia and the United Kingdom to perform the tuberculin skin test (TST). However, this makes it difficult to compare the rates of TST positivity with other countries such as the USA who use 5 TU. To assess the impact of the dose of tuberculin on the TST a comparison was made of TST responses in health care workers given a TST with both 5 and 10 TU.

METHODS

Two TSTs were performed simultaneously in each health care worker using 5 and 10 TU. Each dose was randomly assigned in a blinded manner to the right or left forearm and read at 48-72 hours by a single nurse who was blinded to the assignment of the 5 and 10 TU doses.

RESULTS

A total of 128 health care workers were enrolled, 119 (93%) of whom had a past history of BCG vaccination. The overall mean difference in paired reaction sizes for the two doses was 1.5 mm with 95% limits of agreement of -3.6 to 6.5 mm.

CONCLUSION

A slightly larger TST reading was seen with 10 TU than with 5 TU. The mean difference of 1.5 mm between the two doses should be considered when comparing rates of TST positivity between countries who use different doses of tuberculin to perform the tuberculin skin test.