Effects of age on balance control during walking

OBJECTIVE: To determine the effects of aging on balance control during walking. DESIGN: Two-group repeated-measures design. SETTING: Gait laboratory in Australia. PARTICIPANTS: Convenience sample of 20 healthy older subjects (mean age, 72y) and 20 healthy young subjects (mean age, 24y). INTERVENTIONS: Changes in locomotor performance in response to perturbations to balance were quantified for healthy older adults compared with healthy young adults for (1) straight line walking at preferred speed, (2) straight line walking at fast speed, (3) figure-of-eight walking at preferred speed, and (4) figure-of-eight walking while performing a secondary motor task. MAIN OUTCOME MEASURES: Gait speed, stride length, cadence, and double-limb support duration, using a footswitch system. RESULTS: Healthy older people screened for pathology had gait patterns comparable to young adults for straight line walking at preferred speed. However, multivariate analysis of variance (MANOVA) showed a significant interaction between age and speed when balance was perturbed by requiring subjects to change from walking at preferred to fast speeds (Pillai-Bartlett trace=.259, F(4,35)=3.06, P<.029, partial eta(2)=.259). This occurred because older people did not increase their speed (F(1,38)=7.65, P<.01, partial eta(2)=.168) or stride length (F(1,38)=12.23, P<.01, partial eta(2)=.243) as much as did the young adults. MANOVAs did not show statistically significant interactions between age and turning conditions or age and dual task conditions, although older people walked more slowly and with shorter steps when turning or performing a secondary task. CONCLUSIONS: Balance strategies during gait are task specific and vary according to age. In response to challenges to balance imposed by the requirement to change from preferred to fast walking, older people did not increase their speed and stride length to the same extent as did younger adults. This was possibly a strategy to maintain their stability.     

Neighborhood disadvantage moderates associations of parenting and older sibling problem attitudes and behavior with conduct disorders in African American children

Data from 296 sibling pairs (mean ages 10 and 13 years), their primary caregivers, and census records were used to test the hypothesis that African American children's likelihood of developing conduct problems associated with harsh parenting, a lack of nurturant-involved parenting, and exposure to an older sibling's deviance-prone attitudes and behavior would be amplified among families residing in disadvantaged neighborhoods. A latent construct representing harsh-inconsistent parenting and low levels of nurturant-involved parenting was positively associated with younger siblings' conduct disorder symptoms, as were older siblings' problematic attitudes and behavior. These associations were strongest among families residing in the most disadvantaged neighborhoods. Future research and prevention programs should focus on the specific neighborhood processes associated with increased vulnerability for behavior problems.     

An evidence-based specialist breast nurse role in practice: a multicentre implementation study

The objective of this study was to examine the feasibility, implementation, acceptability and impact of an evidence-based specialist breast care nurse (SBN) model of care in Australia. Primary data were collected from four diverse Australian breast cancer treatment centres over a 12-month period. The design was a multicentre demonstration project. Information about the provision of care and patient needs was collected through prospective logs. Structured interviews were conducted with women who received the SBN intervention ( N  = 167) and with a control group of women treated prior to the intervention period ( N  = 133). Health professionals ( N  = 47) were interviewed about their experience of the SBN. Almost all women had contact with an SBN at five scheduled consultations and 67% of women in the intervention group requested at least one additional consultation with the SBN. Women in the intervention group were more likely to receive hospital fact sheets and to be told about and participate in clinical trials. Ninety-eight per cent of women reported that the availability of an SBN would affect their choice of hospital, with 48% indicating that they would recommend only a hospital with a SBN available. Health professionals reported that SBNs improved continuity of care, information and support for the women, and resulted in more appropriate referrals and use of the time of other members of the team. In conclusion, the SBN model is feasible and acceptable within diverse Australian treatment centres; there is evidence that some aspects of care were improved by the SBN.     

Stress-induced hyperthermia and anxiety: pharmacological validation

When mammals, including man, are confronted with a stressful event, their core body temperature rises, stress-induced hyperthermia. In mice, the stress-induced hyperthermia procedure has been developed to measure antistress or anxiolytic-like effects of psychoactive drugs. Group-housed and singly housed versions of the stress-induced hyperthermia generate comparable results. Because the number of animals needed to perform an experiment is much lower in the singly housed versus the group-housed procedure, the former is the test of choice for pharmacological testing. A typical stress-induced hyperthermia test starts with an injection 60 min before the first rectal temperature measurement (T(1)), followed by a second temperature measurement (T(2)) 10-15 min later. The difference DeltaT (=T(2)-T(1)) is the stress-induced hyperthermia. The procedure also measures the intrinsic activity of drugs on the basal body temperature and DeltaT is relatively independent from the intrinsic temperature effects of drugs. Anxiolytic drugs (benzodiazepines, 5-HT(1A) receptor agonists, alcohol) reduce DeltaT suggestive of anxiolytic-like effects. Because the parameter measured for anxiety in the stress-induced hyperthermia procedure is not dependent on locomotor activity, like in almost all other anxiety tests, the stress-induced hyperthermia procedure is an attractive addition to tests in the anxiety field. Because the stress-induced hyperthermia is also present with a comparable pharmacological profile in females, this procedure has a wide species and gender validity. The procedure was applied in various genetically modified mice [5-HT(1A) and 5-HT(1B) receptor knockout (KO) mice and corticotropin-releasing hormone overexpressing (CRH-OE) mice] to study phenotypic influences of the various mutations on aspects of anxiety. The stress-induced hyperthermia test in singly housed male and female mice appears a useful and extremely simple test to measure effects of drugs on certain aspects of anxiety or to help to determine phenotypic differences in mutant mice.     

Organizational characteristics and restraint use for hospitalized nursing home residents

OBJECTIVES: To examine the effect of organizational characteristics on physical restraint use for hospitalized nursing home residents.
DESIGN: Secondary analysis of data obtained between 1994 to 1997 in a prospective phase lag design experiment using an advanced practice nurse (APN) intervention aimed at reducing physical restraint for a group of hospitalized nursing home residents.
SETTING: Eleven medical and surgical units in one 600-bed teaching hospital.
PARTICIPANTS: One hundred seventy-four nursing home residents aged 61 to 100, hospitalized for a total of 1,085 days.
MEASUREMENTS: Physical restraint use, APN intervention, age, perceived fall risk, behavioral phenomena, perceived treatment interference, mental state, severity of illness, day of week, patient–registered nurse (RN) ratio, patient–total nursing staff ratio, and skill mix.
RESULTS: Controlling for the APN intervention, age, and patient behavioral characteristics (all of which increased the likelihood of restraint use), weekend days as an organizational characteristic significantly increased the odds of restraint (weekend day and patient–RN ratio on physical restraint use: odds ratio (OR) = 1.92, 95% confidence interval (CI) = 1.38–2.68, P < .001; weekend day and patient–total staff ratio on physical restraint use: OR = 1.91, 95% CI = 1.37–2.66, P < .001; weekend day and skill mix on physical restraint use: OR = 1.91, 95% CI = 1.37–2.67, P < .001).
CONCLUSION: Key findings suggest that organization of hospital care on weekends and patient characteristics that affect communication ability, such as severely impaired mental state, English as a second language, sedation, and sensory-perceptual losses, may be overlooked variables in restraint use.