The impact of a meal, snack, or not eating during the night shift on simulated driving performance post-shift.

Objective The commute home following a night shift is associated with an increased risk for accidents. This study investigated the relationship between food intake during the night shift and simulated driving performance post-shift. Methods Healthy non-shift working males (N=23) and females (N=16), aged 18-39 years (mean 24.5, standard deviation 5.0, years) participated in a seven-day laboratory study and underwent four simulated night shifts. Participants were randomly allocated to one of three conditions: meal at night (N=12; 7 males), snack at night (N=13; 7 males) or no eating at night (N=14; 9 males). During the night shift at 00:30 hours, participants either ate a large meal (meal at night condition), a snack (snack at night condition), or did not eat during the night shift (no eating at night condition). During the second simulated night shift, participants performed a 40-minute York driving simulation at 20:00, 22:30, 01:30, 04:00, and 07:30 hours (similar time to a commute from work). Results The effects of eating condition, drive time, and time-on-task, on driving performance were examined using mixed model analyses. Significant condition×time interactions were found, where at 07:30 hours, those in the meal at night condition displayed significant increases in time spent outside of the safe zone (percentage of time spent outside 10 km/hour of the speed limit and 0.8 meters of the lane center; P<0.05), and greater lane and speed variability (both P<0.01) compared to the snack and no eating conditions. There were no differences between the snack and no eating conditions. Conclusion Driver safety during the simulated commute home is greater following the night shift if a snack, rather than a meal, is consumed during the shift.

Altering meal timing to improve cognitive performance during simulated nightshifts.

Altering meal timing could improve cognition, alertness, and thus safety during the nightshift. This study investigated the differential impact of consuming a meal, snack, or not eating during the nightshift on cognitive performance (ANZCTR12615001107516). 39 healthy participants (59% male, age mean±SD: 24.5 ± 5.0y) completed a 7-day laboratory study and underwent four simulated nightshifts. Participants were randomly allocated to: Meal at Night (MN; n= 12), Snack at Night (SN; n = 13) or No Eating at Night (NE; n = 14). At 00:30 h, MN consumed a meal and SN consumed a snack (30% and 10% of 24 h energy intake respectively). NE did not eat during the nightshift. Macronutrient intake was constant across conditions. At 20:00 h, 22:30 h, 01:30 h, and 04:00 h, participants completed the 3-min Psychomotor Vigilance Task (PVT-B), 40-min driving simulator, post-drive PVT-B, subjective sleepiness scale, 2-choice Reaction Time task, and Running Memory task. Objective sleep was recorded for each of the day sleeps using Actigraphy and for the third day sleep, Polysomnography was used. Performance was compared between conditions using mixed model analyses. Significant two-way interactions were found. At 04:00 h, SN displayed increased time spent in the safe zone (p < .001; percentage of time spent within 10 km/h of the speed limit and 0.8 m of lane center), and decreases in speed variability (p < .001), lane variability (p < .001), post-drive PVT-B lapses (defined as RT > 355 ms; p < .001), and reaction time on the 2-choice reaction time task (p < .001) and running memory task (p < .001) compared to MN and NE. MN reported greater subjective sleepiness at 04:00 h (p < .001) compared to SN and NE. There was no difference in objective sleep between eating conditions. Eating a large meal during the nightshift impairs cognitive performance and sleepiness above the effects of time of night alone. For improved performance, shiftworkers should opt for a snack at night.

Subjective Hunger, Gastric Upset, and Sleepiness in Response to Altered Meal Timing during Simulated Shiftwork.

Shiftworkers report eating during the night when the body is primed to sleep. This study investigated the impact of altering food timing on subjective responses. Healthy participants (n = 44, 26 male, age Mean ± SD = 25.0 ± 2.9 years, BMI = 23.82 ± 2.59kg/m2) participated in a 7-day simulated shiftwork protocol. Participants were randomly allocated to one of three eating conditions. At 00:30, participants consumed a meal comprising 30% of 24 h energy intake (Meal condition; n = 14, 8 males), a snack comprising 10% of 24 h energy intake (Snack condition; n = 14; 8 males) or did not eat during the night (No Eating condition; n = 16, 10 males). Total 24 h individual energy intake and macronutrient content was constant across conditions. During the night, participants reported hunger, gut reaction, and sleepiness levels at 21:00, 23:30, 2:30, and 5:00. Mixed model analyses revealed that the snack condition reported significantly more hunger than the meal group (p < 0.001) with the no eating at night group reporting the greatest hunger (p < 0.001). There was no difference in desire to eat between meal and snack groups. Participants reported less sleepiness after the snack compared to after the meal (p < 0.001) or when not eating during the night (p < 0.001). Gastric upset did not differ between conditions. A snack during the nightshift could alleviate hunger during the nightshift without causing fullness or increased sleepiness.

Bioelectrical phase angle values in a clinical sample of ambulatory rehabilitation patients.

BACKGROUND: Phase angle (PhA) is derived from the resistance and reactance measurements obtained from bioelectric impedance analysis (BIA) and is considered indicative of cellular health and membrane integrity. This study measured PhA values of rehabilitation patients and compared them to reference values, measures of functional ability and serum C-reactive protein (CRP) levels to explore their utility as a clinical tool to monitor disease progression and treatment efficacy. METHODS: This cross-sectional observational study was conducted on 215 ambulatory rehabilitation patients aged 20 - 94 years. All participants had been hospitalised for a stroke, orthopaedic or other condition resulting in a functional limitation. PhA was derived from BIA analysis and functional ability characterised using the Functional Independence Measure (FIM), timed up and go (TUG) and maximal quadriceps strength (MQS). Serum levels of CRP were also collected. RESULTS: Stroke patients had the highest PhA (5.3 degrees) followed by elective orthopaedic surgery (5.0 degrees) with the other group (4.3 degrees) significantly lower than both previous categories (p < 0.001). Ambulatory rehabilitation patients' PhA values were dependent on age and sex (p < 0.001), lower than published age matched healthy reference values (p < or = 0.05) and similar to other hospitalised or sick groups, but also higher than values reported in critically ill patients. Patients with CRP values less than 10 mg.L-1 had significantly (p = 0.005) higher mean PhA values. Furthermore, the highest functional status quartiles had significantly higher PhAs (p < or = 0.04) for the FIM, MQS and TUG measures. CONCLUSION: The results suggest that the phase angles of rehabilitation patients are between those of healthy individuals and seriously ill patients, thereby supporting claims that PhA is indicative of general health status. Phase angles are a potentially useful indicator of functional status in patients commencing an ambulatory rehabilitation program with a normal hydration status.

Perspectives of carers on the move from a hospital to a transitional care unit.

The authors describe carers' experiences of the traditional process of moving a relative into residential care from an acute hospital admission and how a transitional care unit affected this experience. Telephone interviews (total 31) confirmed that looking for permanent care was a stressful, time-consuming, and confusing process for all carers. The transitional care unit did not make a great difference to the stress of finding a residential care vacancy, but the overall experience of transitional care was positive, with carers feeling that it gave them time to consider residential care options. Carers felt that a hospital was not the best environment to assess ongoing care needs. The implementation of transitional care did not reduce the stress felt by carers when looking for a residential care facility, but it was an acceptable alternative to waiting for residential care in hospital.

Aldehyde dehydrogenase, nitric oxide synthase and superoxide in ex vivo nitrate tolerance in rat aorta.

The role of aldehyde dehydrogenase (ALDH) in ex vivo tolerance to transdermal glyceryl trinitrate was explored in rat aorta. ALDH activity, measured by aldehyde-induced NADH formation, was strongly depressed in the tolerant arteries. ALDH inhibitors, chloral hydrate (0.3 mM) and cyanamide (0.1-1 mM) inhibited relaxation to glyceryl trinitrate in non-tolerant and tolerant arteries. The inhibition differed from tolerance in that (a) the glyceryl trinitrate concentration-response curve was sigmoidal cf. biphasic in tolerance, (b) the potentiating effect of nitric oxide synthase (eNOS) inhibition was unchanged cf. increased in tolerance and (c) superoxide inhibited the response cf. no significant effect in tolerant or non-tolerant arteries. Hence, reduced ALDH activity does not account fully for ex vivo tolerance. The discrepancies are consistent with evidence that (a) organic nitrates, unlike chloral and cyanamide, irreversibly inactivate ALDH (hence reduced enzyme saturability can explain the biphasic curve) and (b) eNOS contributes to tolerance by a mechanism independent of glyceryl trinitrate metabolism.

Removable rigid dressings: a retrospective case-note audit to determine the validity of post-amputation application.

This study investigated the validity of post-amputation application of removable rigid dressings (RRDs) for trans-tibial amputees, regarding preparation for prosthetic management and key rehabilitation timelines. It was hypothesised that the use of RRDs would result in faster preparation of the residual limb for prosthetic management and shorter rehabilitation times, compared with conventional soft dressings. A retrospective case-note audit was conducted, in which consecutive trans-tibial amputees who underwent amputation in the 2 years before RRD implementation (non-RRD group, n = 37) and in the 2 years after RRD implementation (RRD group, n = 28) were eligible for inclusion. There was a significant reduction in the geometric mean time-to-first-prosthetic-casting in the RRD group, compared with the soft-dressing group (36.4 days vs. 27.6 days, respectively, p < 0.05). A significant reduction in acute length of stay (LOS) for the RRD group was also identified (15.9 days vs. 8.7 days, respectively, p < 0.001). There were no significant differences in other rehabilitation timeframes, such as rehabilitation LOS, total LOS, outpatient rehabilitation days, and total rehabilitation days between the two groups. This study shows that the application of RRDs reduces acute LOS and time-to-first-prosthetic-casting, thereby providing substantial benefits in preparing the trans-tibial amputee for early rehabilitation and prosthetic intervention.

Activity levels among lower-limb amputees: self-report versus step activity monitor.

OBJECTIVE: To determine the accuracy of self-reported activity by community-dwelling, lower-limb amputees. DESIGN: Descriptive study. SETTING: A regional prosthetics outpatient service. PARTICIPANTS: Seventy-seven unilateral lower-limb amputees at least 6 months after prosthetic rehabilitation. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Measured activity counts (in steps/min) and self-reported activity (rest, low, medium, high) in 15-minute intervals over 1 week were recorded for each participant. RESULTS: Participants averaged 3063+/-1893 steps per day. Strong agreement (gamma> or =0.7) between self-reported and measured activity was found for only 34% of participants between the hours of 9:00 am to 9:00 pm. The measured and self-reported proportion of time spent in various states of activity also showed poor agreement (rest, r=.41; low level activity, r=.39; medium level, r=.26; high level, r=.40). There was no bias toward either over- or under-reporting. CONCLUSIONS: The majority of participants were unable to accurately self-report their activity levels (sleep excluded) as compared with measured activity levels. This may have important implications for prescribing appropriate prosthetics and for clinicians who provide patients with advice on promoting health.

Pilot study examining the effect of cholesterol lowering on platelet nitric oxide responsiveness and arterial stiffness in subjects with isolated mild hypercholesterolaemia.

1. Hypercholesterolaemia has been associated with impaired endothelial function. However, there are no available data as to whether hypercholesterolaemia is also associated with platelet dysfunction. 2. In a group of asymptomatic adults with (n = 16) and without (n = 13) mild hypercholesterolaemia, we evaluated inhibition of platelet aggregation in response to the nitric oxide (NO) donor sodium nitroprusside (SNP), as well as the augmentation index (AIx), a parameter of arterial stiffness that is impaired in the presence of endothelial dysfunction. 3. Neither SNP response nor AIx varied significantly between normocholesterolaemic (NC) and hypercholesterolaemic (HC) subjects. 4. Three months treatment with pravastatin (40 mg/day) in HC subjects lowered mean (+/-SEM) total cholesterol levels from 6.6 +/- 0.2 to 5.5 +/- 0.2 mmol/L. Platelet response to SNP increased in platelet-rich plasma and tended to increase in whole blood. The AIx did not change significantly. However, falls in low-density lipoprotein (P = 0.03) and total cholesterol (P = 0.08) correlated with reductions in AIx in individual subjects. 5. These data provide evidence that moderate reduction of cholesterol levels may improve platelet responses to NO, whereas improvement in arterial stiffness may be detectable only with more extensive and/or a prolonged reduction in cholesterol levels.