Protein and energy balance following femoral neck fracture in geriatric patients

The ratio of energy expenditure to nitrogen loss in diverse patient groups--a systematic review

BACKGROUND & AIMS

The ratio of energy expenditure to nitrogen loss respectively of energy to nitrogen provision (E/N) is considered a valuable tool in the creation of an enteral or parenteral formulation. Specific E/N ratios for parenteral nutrition (PN) have not yet been clearly defined. To determine the range of energy expenditure, nitrogen (protein) losses, and E/N ratios for various patient groups, we performed a systematic review of the literature.

METHODS

Medline 1950-2011 was searched for all studies on patients or healthy controls reporting energy expenditure and nitrogen loss at the same time.

RESULTS

We identified 53 studies with 91 cohorts which comprised 1107 subjects. Mean TEE ± standard deviation (SD) was 31.2 ± 7.2 kcal/kg BW/day in patients (n = 881) and 35.6 ± 4.3 kcal/kg BW/day in healthy controls (n = 266). Mean total protein loss (TPL) was 1.50 ± 0.57 g/kg BW/day in patients and 0.94 ± 0.24 g/kg BW/day in healthy controls. A non-linear significant correlation was found between TPL and the E/N ratio.

CONCLUSION

The E/N ratio is not a constant value but decreases continuously with increasing protein loss. These variations should be considered in the nutritional support of patients.

A fracture does not adversely affect bone mineral density responses after teriparatide treatment

BACKGROUND

Fracture leads to local and systemic catabolic physiologic changes. As teriparatide is an agent used to treat osteoporosis in patients with fragility fractures, it is unclear whether teriparatide treatment alters bone mineral density (BMD) and bone markers when given to patients with fractures.

QUESTIONS/PURPOSES

We asked whether BMD and bone marker responses would be blunted in patients with fractures placed on teriparatide after fracture compared with patients without fractures on teriparatide.

PATIENTS AND METHODS

We retrospectively collected data from 141 patients treated with teriparatide for osteoporosis. Seventy-seven patients received teriparatide after fractures (fracture group), whereas 64 were treated for other indications (nonfracture group). We determined BMD at the lumbar spine and at the proximal femur before and 12 and 24 months posttreatment. Bone markers (urine N-telopeptide [urine NTX], bone-specific alkaline phosphatase [BALP]) were measured at baseline and 3, 12, and 24 months posttreatment.

RESULTS

Mean lumbar spine and hip BMDs at last followup increased from baseline with no differences between groups to approximately 9% and 4% at 24 months, respectively. Both bone markers increased from baseline in the nonfracture group, peaking at 12 months. For the fracture group, only urine NTX increased at 3 and 12 months posttreatment. Although the peak levels of both bone markers in the nonfracture group were greater, there was no difference between the two groups.

CONCLUSIONS

Fracture does not have a negative effect on the BMD and bone marker responses to teriparatide treatment. Clinicians should anticipate comparable BMD responses when treating patients with teriparatide for osteoporotic fractures and for other indications.

LEVEL OF EVIDENCE

Level III, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

A trial assessing N-3 as treatment for injury-induced cachexia (ATLANTIC trial): does a moderate dose fish oil intervention improve outcomes in older adults recovering from hip fracture?

BACKGROUND

Proximal femoral fractures are associated with increased morbidity and mortality. Pre-existing malnutrition and weight loss amongst this patient group is of primary concern, with conventional nutrition support being largely ineffective. The inflammatory response post proximal femoral fracture surgery and the subsequent risk of cachexia may explain the inability of conventional high energy high protein management to produce an anabolic response amongst these patients. Omega-3 fatty acids derived from fish oils have been extensively studied for their anti-inflammatory benefits. Due to their anti-inflammatory properties, the benefit of fish oil combined with individualized nutrition support amongst proximal femoral fracture patients post surgery is an attractive potential therapeutic strategy. The aim of the ATLANTIC trial is to assess the potential benefits of an anti-inflammatory dose of fish oil within the context of a 12 week individualised nutrition program, commencing seven days post proximal femoral fracture surgery.

METHODS/DESIGN

This randomized controlled, double blinded trial, will recruit 150 community dwelling elderly patients aged ≥65 years, within seven days of surgery for proximal femoral fracture. Participants will be randomly allocated to receive either a 12 week individualized nutrition support program complemented with 20 ml/day anti-inflammatory dose fish oil (~3.6 g eicosapentaenoic acid, ~2.4 g docosahexanoic acid; intervention), or, a 12 week individualized nutrition support program complemented with 20 ml/day low dose fish oil (~0.36 g eicosapentaenoic acid, ~0.24 g docosahexanoic acid; control).

DISCUSSION

The ATLANTIC trial is the first of its kind to provide fish oil combined with individualized nutrition therapy as an intervention to address the inflammatory response experienced post proximal femoral fracture surgery amongst elderly patients. The final outcomes of this trial will assist clinicians in the development of effective and alternative treatment methods post proximal femoral fracture surgery which may ultimately result in a reduction in systemic inflammation, loss of weight and lean muscle and improvements in nutritional status, mobility, independence and quality of life among elderly patients.

TRIAL REGISTRATION

ACTRN12609000241235.

Nutritional status and energy expenditure in elderly patients with recent hip fracture during a 2-month follow-up

A 2-month follow-up of nutritional status was performed in forty elderly patients with recent hip fracture. Patients were nutritionally assessed on admission to our rehabilitation unit (day 0), then monthly (day 30, day 60) by measurement of resting energy expenditure (REE), anthropometric, impedance and biological variables. Patients were defined as undernourished (n 13) or normally nourished (n 27) on the basis of mid-arm circumference (MAC) and triceps skinfold thickness (TST) measurements. Seven patients recovered a walking autonomy and were discharged from the hospital before day 30 (group I) whereas thirteen patients were discharged after day 30 (group II); twenty patients remained in the study at day 60 (group III). MAC and TST decreased in normally nourished patients from group III throughout the study whereas they did not change in group II or in undernourished patients from group III. REE values in relation to fat-free mass were increased compared with normal values and were similar in the three groups on day 0; they did not change during the study. Daily energy intake in relation to body weight was higher in group I and increased in group II and in undernourished patients from group III throughout the study. In contrast, it was below the recommended value at day 0 and it did not significantly improve in normally nourished patients from group III. Serum albumin, transthyretin and transferrin levels on day 0 were below reference intervals in the three groups. Albumin levels increased in group III throughout the study. Inflammatory proteins decreased in groups II and III, with C-reactive protein levels returning to normal values in group II by day 30 and in group III at day 60, while orosomucoid levels did not become completely normal over this period. Our findings indicate no improvement in nutritional status in undernourished patients after surgery for recent hip fracture, despite an adequate energy intake. An insufficient spontaneous energy intake for normally nourished patients was associated with a delayed favourable outcome resulting in a prolonged duration of hospitalization. A hypermetabolic state persisted during the 3 months after surgery.

Resting energy expenditure measured longitudinally following hip fracture compared to predictive equations: is an injury adjustment required?

The present study measuring resting energy expenditure (REE; kJ/d) longitudinally using indirect calorimetry in six elderly women aged ≥70 years following surgery for hip fracture, describes changes over time (days 10, 42 and 84 post-injury) and compares measured values to those calculated from routinely applied predictive equations. REE was compared to REE predicted using the Harris Benedict and Schofield equations, with and without accounting for the theoretical increase in energy expenditure of 35 % secondary to physiological stress of injury and surgery. Mean (95 % CI) measured REE (kJ/d) was 4704 (4354, 5054), 4090 (3719, 4461) and 4145 (3908, 4382) for days 10, 42 and 84, respectively. A time effect was observed for measured REE,P=0·003. Without adjusting for stress the mean difference and 95 % limits of agreement for measured and predicted REE (kJ/kg per d) for the Harris Benedict equation were 1 (−9, 12), 10 (2, 18) and 9 (1, 17) for days 10, 42 and 84, respectively. The mean difference and 95 % limits of agreement for measured and predicted REE (kJ/kg per d) for the Schofield equation without adjusting for stress were 8 (−3, 19), 16 (6, 26) and 16 (10, 22) for days 10, 42 and 84, respectively. After adjusting for stress, REE predicted from the Harris Benedict or Schofield equations overestimated measured REE by between 38 and 69 %. Energy expenditure following fracture is poorly understood. Our data suggest REE was relatively elevated early in recovery but declined during the first 6 weeks. Using the Harris Benedict or Schofield equations adjusted for stress may lead to overestimation of REE in the clinical setting. Further work is required to evaluate total energy expenditure before recommendations can be made to alter current practice for calculating theoretical total energy requirements of hip fracture patients.