Alberto Cavanna

Hepatic clearance of D-sorbitol: noninvasive test for evaluating functional liver plasma flow

The hepatic clearance of D-sorbitol, a natural polyol which is metabolized by the liver, was studied in normal and cirrhotic subjects after bolus intravenous injection (2 g) and during constant infusion (54 mg/min) with the aim of providing a noninvasive and simple measure of functional liver plasma flow. The high hepatic extraction of D-sorbitol and the dose-independence of its clearance pointed to a flow-dependent clearance regimen. The renal excretion was taken into account when computing the hepatic clearance. Day-to-day reproducibility of the test was good. No significant difference was found when the hepatic clearance was measured by bolus injection or constant infusion methods. As measured by the bolus injection method, the mean (+/- SD) hepatic clearance in the normal subjects (911 +/- 137 ml/min) was significantly greater (P less than 0.001) than that of the cirrhotics (456 +/- 181 ml/min).The hepatic clearance ofd-sorbitol, a natural polyol which is metabolized by the liver, was studied in normal and cirrhotic subjects after bolus intravenous injection (2 g) and during constant infusion (54 mg/min) with the aim of providing a noninvasive and simple measure of functional liver plasma flow. The high hepatic extraction ofd-sorbitol and the dose-independence of its clearance pointed to a flow-dependent clearance regimen. The renal excretion was taken into account when computing the hepatic clearance. Day-today reproducibility of the test was good. No significant difference was found when the hepatic clearance was measured by bolus injection or constant infusion methods. As measured by the bolus injection method, the mean (±sd) hepatic clearance in the normal subjects (911±137 ml/min) was significantly greater (P<0.001) than that of the cirrhotics (456±181 ml/min).

The relationship between initial trunk control or postural balance and inpatient rehabilitation outcome after stroke: a prospective comparative study

Objective: To compare the predictive validity of trunk control in sitting position assessed by Trunk Impairment Scale and balance in lying, sitting and standing posture assessed by Postural Assessment Scale for Stroke patients on functional outcome in stroke survivors. Design: Prospective observational study. Setting: A single rehabilitation hospital in Italy. Subjects: Sixty of 68 consecutive subjects admitted to a rehabilitation hospital after stroke. Main measures: We performed Trunk Impairment Scale and Postural Assessment Scale for Stroke patients at admission to inpatient rehabilitation. Outcome measures at discharge were Functional Independence Measure score and destination (classified as either home or institution). Results: After adjustment for 14 potential confounders, including Functional Independence Measure score at admission to rehabilitation, both Trunk Impairment Scale and Postural Assessment Scale for Stroke patients scores were significantly associated with the Functional Independence Measure score at discharge (P = 0.010 and P =0.04, respectively), change in the Functional Independence Measure score during rehabilitation (P = 0.003 and P<0.001, respectively), Functional Independence Measure effectiveness (P = 0.024 and P =0.017, respectively) and destination at discharge (P = 0.040 and P =0.032, respectively). The panel of prognostic variables predicted 64—65% of the variance in the final Functional Independence Measure score, 30—35% of the variance in the change of the Functional Independence Measure score during rehabilitation, and 45—46% of the variance in the Functional Independence Measure effectiveness depending on the inclusion of either Trunk Impairment Scale or Postural Assessment Scale for Stroke patients score among the predictors. Conclusions: Both trunk performance in sitting position and balance in lying sitting and standing posture after stroke predicted functional ability and destination at discharge from inpatient rehabilitation. Scores from the Postural Assessment Scale for Stroke patients may have a slightly better prognostic value than scores from the Trunk Impairment Scale.

Muscle mass and functional recovery in women with hip fracture.

Di Monaco M, Vallero F, Di Monaco R, Tappero R, Cavanna A: Muscle mass and functional recovery in women with hip fracture. Am J Phys Med Rehabil 2006;85:209–215. Objective:To investigate the association between muscle mass and functional recovery in women with hip fracture. Design:A total of 200 of 230 women with hip fracture admitted consecutively to a rehabilitation hospital were investigated in this survey study. Lean mass (LM) was assessed by dual-energy x-ray absorptiometry, 23.1 ± 7.9 (mean ± SD) days after fracture occurrence. Appendicular LM (aLM) was calculated as the sum of LM in arms and legs. Because metal implants (prostheses and nails) affect the regional assessment of body composition, aLM was corrected by substituting LM in the unfractured leg for LM in the fractured leg: corrected aLM = (LM in unfractured leg × 2) + LM in arms. We used two approaches to adjust corrected aLM for body size: corrected aLM divided by height squared (aLM/ht2), and corrected aLM adjusted for height and fat mass (residuals). Functional recovery was assessed by using Barthel index scores. Results:After adjustment for body size, corrected aLM was neither significantly correlated with Barthel index scores nor with the change in Barthel index scores after rehabilitation. Also, after stratification for quintiles of aLM/ht2 and residuals, no significant differences in functional recovery were found among the five groups. Conclusions:LM assessed after hip fracture is not associated with functional outcome in women.

Skeletal muscle mass, fat mass, and hip bone mineral density in elderly women with hip fracture

Soft tissue body composition strongly affects bone health. Our aim was to investigate the relationship between both skeletal muscle mass (SMM) and fat mass (FM) and femoral bone mineral density (BMD) in a sample of elderly women with hip fracture. We assessed 293 of 325 hip fracture women admitted consecutively to a rehabilitation hospital. Soft tissue body composition and BMD were assessed by dual-energy X-ray absorptiometry (DXA), 23.2 ± 7.7 (mean ± SD) days after fracture occurrence. BMD was measured at four sites (neck, total femur, trochanter, intertrochanteric area) in the unfractured femur. Appendicular lean mass (aLM) was calculated as the sum of LM in arms and legs. We used two approaches to adjust aLM for body size: aLM divided by height squared (aLM/ht2), and aLM adjusted for height and FM (residuals). Both FM and aLM were significantly correlated with femoral BMD. However, the correlation coefficients for aLM were lower than for FM; they further decreased after adjustment for height squared, and were no longer significant after correction for both height and FM (residuals). When FM, aLM/ht2, age, and time spent between fracture occurrence and DXA assessment were included together as the independent variables in a regression model, FM was the only independent variable significantly associated with BMD. The coefficients of partial correlation ranged from 0.414 to 0.647 depending on the femoral region of BMD assessment (P < 0.001). FM, but not SMM emerged as a pivotal determinant of BMD in our sample of hip fracture women.

25-Hydroxyvitamin D, parathyroid hormone, and functional recovery after hip fracture in elderly patients

There is increasing interest in the effects of vitamin D and parathyroid hormone (PTH) on extraskeletal tissues, including the muscle. These effects may explain impairment in functional ability found in vitamin D-deficient subjects. Our aim was to investigate the roles of vitamin D and PTH in affecting the ability to perform activities of daily living after hip fracture. We studied 456 of 521 hip-fracture patients admitted consecutively to a rehabilitation hospital. Functional outcome was assessed after acute inpatient rehabilitation by using the Barthel index score. The functional scores were significantly correlated with serum levels of 25-hydroxyvitamin D (ρ = 0.190; P < 0.001) and PTH (ρ = −0.164; P < 0.001) and the 25-hydroxyvitamin D/PTH ratio (ρ = 0.261; P < 0.001). At multiple regression, 25-hydroxyvitamin D and PTH levels were independently associated with Barthel index scores. The correlation between the 25-hydroxyvitamin D/PTH ratio and Barthel index scores was significantly stronger than the one between 25-hydroxyvitamin D and Barthel index scores (difference between the two correlation coefficients = 0.071; 95% CI = 0.009–0.133; P = 0.011). The significant association between the 25-hydroxyvitamin D/PTH ratio and the Barthel index scores persisted after adjustment for 12 prognostic factors (P = 0.012). On the whole, the panel of prognostic factors we studied predicted 50.1% of the variance of the functional score. Data shows that PTH and 25-hydroxyvitamin D were significantly associated with the ability to function after hip fracture and suggest that the two hormones act through independent mechanisms. The 25-hydroxyvitamin D/PTH ratio significantly contributed to a predictive model of functional outcome.

Body mass index and functional recovery after hip fracture: a survey study of 510 women

Background and aims: Low body mass index (BMI) is associated with high risk of osteoporosis and fractures, but its impact on functional recovery after fractures is unknown. Our aim was to investigate the association between BMI and both functional recovery and period of rehabilitation in hip-fractured women. Methods: 510 out of 580 Caucasian women with hip fracture, admitted consecutively to a rehabilitation hospital, were investigated in this retrospective study. Functional recovery was assessed using the Barthel index score. Results: In the 510 women, BMI was 22.8±4.1 kg/m2 (mean±SD). After adjustment for age, femur bone mineral density, and the Barthel index assessed on admission to rehabilitation, a significant negative association was found between BMI and both the Barthel index score after rehabilitation and changes in it resulting from rehabilitation (p≤0.001). After adjustment for age and the Barthel index assessed on admission to rehabilitation, a significant positive association was found between BMI and period of rehabilitation (p≤0.001). The results were similar when BMI was evaluated either as individual values or after categorization according to World Health Organization criteria. Conclusions: In a sample of hip-fractured women, BMI was negatively associated with Barthel index scores and positively associated with period of rehabilitation. BMI may affect function after hip fracture, apart from hip fracture risk: subjects with higher BMI and low hip fracture risk may have poorer functional recovery in case of hip fracture, despite prolonged rehabilitation. Conversely, subjects with lower BMI and high hip fracture risk may have better functional recovery in case of hip fracture.

Type of Hip Fracture in Patients With Parkinson Disease is Associated With Femoral Bone Mineral Density

OBJECTIVEnTo investigate the association between bone mineral density (BMD) and hip fracture type (cervical or trochanteric) in a sample of fallers with Parkinson disease (PD).nnnDESIGNnObservational study.nnnSETTINGnRehabilitation hospital in Italy.nnnPATIENTSnWe investigated 1040 of 1120 white fallers consecutively admitted to a rehabilitation hospital for hip fracture. Thirty-eight (3.65%) of the 1040 patients suffered from PD secondarily. Thirty-eight controls matched for sex, age, and hip fracture type were found among the 1002 non-PD fallers.nnnINTERVENTIONSnNot applicable.nnnMAIN OUTCOME MEASURESnBMD was assessed by dual-energy x-ray absorptiometry at a mean+/-SD of 21.9+/-7.5 days after fracture occurrence in the 38 PD patients and 21.6+/-5.9 days after fracture occurrence in the 38 controls.nnnRESULTSnBMD assessed at total femur, trochanter, and intertrochanteric region was significantly lower in the 15 PD patients with trochanteric fractures than in the 23 with cervical fractures; the mean T score differences were 0.57 (95% confidence interval [CI], 0.07-1.08; P=.028), 0.66 (95% CI, 0.04-1.28; P=.037), and 0.63 (95% CI, 0.11-1.15; P=.019), respectively. A significant association between femoral BMD and hip fracture type was found at logistic regression after adjustment for several confounders. Results in the 38 controls were similar to those obtained in the 38 PD fallers.nnnCONCLUSIONSnIn a sample of PD fallers as in a control group of non-PD fallers, BMD levels assessed at 3 femoral sites were significantly lower in the patients who sustained trochanteric fractures than in those with cervical fractures of the hip.

Non-invasive evaluation of portal-systemic shunting in man by d-sorbitol bioavailability

Portal-systemic shunting is an important circulatory abnormality in patients with cirrhosis. This study explores the potential of the natural polyol D-sorbitol as test compound for non-invasive assessment of shunting. Ten normal subjects, 10 patients with cirrhosis and 12 cirrhotics with surgical portacaval shunts were studied after oral and intravenous administration of a 2 g dose of sorbitol. As measured by the H2 breath test, removal from the intestinal lumen was complete in both groups. Bioavailability of sorbitol, calculated as ratio of the areas under the plasma concentration/time curve after p.o. and i.v. administration, was zero in normal subjects, 0.29 +/- 0.15 in cirrhotic patients, and 0.38 +/- 0.11 in patients with portacaval shunts. Calculation of bioavailability on the basis of urinary outputs of sorbitol gave similar results. It is concluded that the bioavailability of sorbitol reflects portal-systemic shunting, although the relatively low figures suggest some degree of sorbitol metabolism by enterocytes.

Incident falls impair ability to function in hip-fracture survivors: A prospective study of 95 elderly women

The present study focused on home-dwelling women successfully discharged back to the community after a fall-related fracture of the hip. We investigated the role of incident falls in affecting ability to function in activities of daily living. Ninety-five of 103 consecutive women without cognitive impairment were recruited during in-patient rehabilitation following their first hip fracture. Functional independence in activities of daily living was assessed by using the Barthel Index (BI) score at discharge from in-patient rehabilitation and at a 6-month follow-up. Nineteen of the 95 women sustained one or more falls during a median observation time of 187 days. At a Mann-Whitney test, both BI scores assessed at the 6-month follow-up and gains in BI scores during the follow-up were significantly lower in the 19 fallers than in the 76 non-fallers (p=0.021 and p=0.030, respectively), whereas no significant differences were found in baseline BI scores between the two groups. At linear multiple regression, we found a negative association between incident falls and both functional scores (p=0.01) and their gains (p=0.006) after adjustment for several confounders. We conclude that incident falls were significantly associated with a worse functional score in our sample of hip-fracture women.

D-Sorbitol plasma disappearance rate: An index to evaluate changes in liver circulation

SummaryThe hepatic clearance of D-sorbitol was proven to be a reliable parameter for evaluating the functional liver plasma flow. Twenty-five normal subjects and 50 cirrhotic patients were studied in order to assess if the measure of the plasma disappearance rate of sorbitol can be used as a simpler procedure to evaluate changes in liver perfusion and to predict modifications of drug bioavailability due to circulatory events. The plasma disappearance rate was calculated between 10 and 20 min after intravenous administration of a 2-g dose because in this time interval plasma levels were in the optimum range for the chemical assay, and the plasma concentration/time curve fitted a decreasing exponential function. Plasma disappearance rate values were found to correlate significantly (r = 0.666, p<0.001) with sorbitol hepatic clearance, as calculated after the 2-h test. The test had a good day-to-day reproducibility both in normal subjects and cirrhotic patients. In 5 patients submitted to surgical side-to-side portacaval shunt, decreases of plasma disappearance rate and sorbitol hepatic clearance showed no significant difference. Mean values (± SD) of D-sorbitol plasma disappearance rate were 0.048 ± 0.014 min-1 in cirrhotic patients, and 0.081 ± 0.014 min-1 in normal subjects (p<0.001).