Predictors of Energy Compensation during Exercise Interventions: A Systematic Review

Weight loss from exercise-induced energy deficits is usually less than expected. The objective of this systematic review was to investigate predictors of energy compensation, which is defined as body energy changes (fat mass and fat-free mass) over the total amount of exercise energy expenditure. A search was conducted in multiple databases without date limits. Of 4745 studies found, 61 were included in this systematic review with a total of 928 subjects. The overall mean energy compensation was 18% ± 93%. The analyses indicated that 48% of the variance of energy compensation is explained by the interaction between initial fat mass, age and duration of exercise interventions. Sex, frequency, intensity and dose of exercise energy expenditure were not significant predictors of energy compensation. The fitted model suggested that for a shorter study duration, lower energy compensation was observed in younger individuals with higher initial fat mass (FM). In contrast, higher energy compensation was noted for younger individuals with lower initial FM. From 25 weeks onward, energy compensation was no longer different for these predictors. For studies of longer duration (about 80 weeks), the energy compensation approached 84%. Lower energy compensation occurs with short-term exercise, and a much higher level of energy compensation accompanies long-term exercise interventions.     

Evidence for a Physiologic Role of Erythropoietin in Fetal Erythropoiesis

Administration of antibody prepared inrabbits against human urinary Ep to fetalsheep during the last third of the gestation period resulted in a suppression oferythropoiesis in the fetus. This wasevidenced by a sharp decrease in the numbers of circulating reticulocytes and a reduced rate of ⁵⁹Fe incorporation into RBC,spleen, and bone marrow, effects ascribable to a neutralization of endogenous Ep.In addition, there was a significant decrease in the numbers of nucleated erythroid cells in the bone marrows of thesefetuses. These results point to a physiologic role for Ep in fetal erythropoiesis.

Submitted on December 17, 1973 Revised on February 19, 1974 Accepted on February 20, 1974     

Pulmonary function in primary pulmonary hypertension

OBJECTIVES: The study was done to ascertain the degree to which abnormalities in resting lung function correlate with the disease severity of patients with primary pulmonary hypertension (PPH). BACKGROUND: Patients with PPH are often difficult to diagnose until several years after the onset of symptoms. Despite the seriousness of the disorder, the diagnosis of PPH is often delayed because it is unsuspected and requires invasive measurements. Although PPH often causes abnormalities in resting lung function, these abnormalities have not been shown to be statistically significant when correlated with other measures of PPH severity. METHODS: Resting lung mechanics and diffusing capacity for carbon monoxide DL(CO) were assessed in 79 patients whose findings conformed to the classical diagnostic criteria of PPH and who had no evidence of secondary causes of pulmonary hypertension. These findings were correlated with severity of disease as assessed by cardiac catheterization, New York Heart Association (NYHA) class, and cardiopulmonary exercise testing. RESULTS: When PPH patients were first evaluated at our referral clinic, the DL(CO) and lung volumes were decreased in approximately three-quarters and one-half, respectively. The decreases in DL(CO), and to a lesser extent lung volumes, correlated significantly with decreases in peak oxygen uptake (reflecting maximum cardiac output), peak oxygen pulse (reflecting maximum stroke volume), and anaerobic threshold (reflecting sustainable exercise capacity) and higher NYHA class. CONCLUSIONS: Patients with PPH commonly have abnormalities in lung mechanics and DL(CO) levels that correlate significantly with disease severity. These measurements can be useful in evaluating patients with unexplained dyspnea and fatigue.     

Modifiable Failures in the Colorectal Cancer Screening Process and Their Association With Risk of Death

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Physical therapy and mobility 2 and 6 months after hip fracture

OBJECTIVES: To examine the relationship between early physical therapy (PT), later therapy, and mobility 2 and 6 months after hip fracture. DESIGN: Prospective, multisite observational study. SETTING: Four hospitals in the New York City area. PARTICIPANTS: Four hundred forty-three hospitalized older patients discharged after surgery for hip fracture in 1997-98. MEASUREMENTS: Patient demographics, fracture type, comorbidities, dementia, number of new impairments at discharge, amount of PT between day of surgery and postoperative day (POD) 3, amount of therapy between POD4 and 8 weeks later, and prefracture, 2-, and 6-month mobility measured using the Functional Independence Measure. RESULTS: More PT immediately after hip fracture surgery was associated with significantly better locomotion 2 months later. Each additional session from the day of surgery through POD3 was associated with an increase of 0.4 points (P=.032) on the 14-point locomotion scale, but the positive relationship between early PT and mobility was attenuated by 6 months postfracture. There was no association between later therapy and 2- or 6-month mobility. CONCLUSION: PT immediately after hip fracture surgery is beneficial. The effects of later therapy on mobility were difficult to assess because of limitations of the data. Well-designed randomized, controlled trials of the effect of varying schedules and amounts of therapy on functional status after hip fracture would be informative.     

Sudden death in severe aortic stenosis following cardiac catheterization

Five patients with critical aortic stenosis (aortic valve area 0.6 cm² or less) died 2 days to 21 days following cardiac catheterization performed in anticipation of cardiac surgery. A sixth patient was successfully resuscitated for spontaneous ventricular fibrillation, and successful aortic valve replacement was accomplished. Two patients had prior history of syncope; one patient, of ventricular tachycardia; three patients, of pulmonary edema; and three patients, of crescendo angina. One patient had severe hypotension during maintenance hemodialysis for chronic renal failure. The mode of death was sudden but not witnessed in two patients. The terminal cardiac rhythms were slow junctional in one patient, idioventricular in one, ventricular tachycardia in one, and ventricular fibrillation in the fourth patient. We conclude that symptomatic patients with critical aortic stenosis should be monitored after cardiac catheterization, and surgery should be performed as soon as possible since sudden death is not unusual.     

Patient protection and risk selection

BACKGROUND: Individual physicians who are paid prospectively, as in capitated health plans, might tend to encourage patients to avoid or to join these plans according to the patient's health status. Though insurance risk selection has been well documented among organizations paid on a prospective basis, such physician-level risk selection has not been studied. OBJECTIVE: To assess physician reports of risk selection in capitated health plans and explore potentially related factors. DESIGN AND PARTICIPANTS: National mailed survey of primary care physicians in 1997-1998, oversampling physicians in areas with more capitated health plans. RESULTS: The response rate was 63% (787 of 1,252 eligible recipients). Overall, 44% of physicians reported encouraging patients either to join or to avoid capitated health plans according to the patients' health status: 40% encouraged more complex and ill patients to avoid capitated plans and 23% encouraged healthier patients to join capitated plans. In multivariable models, physicians with negative perceptions of capitated plan quality, with more negative experiences in capitated plans, and those who knew at each patient encounter how they were being compensated had higher odds of encouraging sicker patients to avoid capitated plans (odds ratios, 2.0, 2.2, and 2.0; all confidence intervals >1). CONCLUSIONS: Many primary care physicians report encouraging patients to join or avoid capitated plans according to the patient's health status. Although these physicians' recommendations might be associated primarily with concerns about quality, they can have the effect of insulating certain health plans from covering sicker and more expensive patients.     

Dynamics of oxygen uptake during exercise in adults with cyanotic congenital heart disease

The dynamic increase in oxygen uptake (VO2) at the start of exercise reflects the circulatory adjustments to metabolic changes induced by the exercise. Because VO2 measured at the lungs is the product of pulmonary blood flow and arteriovenous oxygen difference, pathologic conditions affecting the capacity of these factors to change would be expected to alter VO2 kinetics. To determine whether measurement of VO2 kinetics can detect conditions in which the pulmonary blood flow response to exercise is abnormal, VO2 was measured, breath-by-breath, during the transition from rest to exercise in 13 adults with cyanotic congenital heart disease (central venoarterial shunting) and in nine normal subjects. The increase in VO2 above baseline during the first 20 sec of exercise (phase I), reflecting the immediate increase in pulmonary blood flow, was diminished in the patients compared with that in normal subjects (14.8 +/- 10.9 vs. 49.8 +/- 19.2 ml of oxygen) (p less than .001). The patients' phase I responses correlated with their reported physical activity tolerance (p less than .01). In addition, the second phase of the VO2 response kinetics was prolonged in patients compared with normal subjects (half-time = 63 +/- 13 vs 15 +/- 13 sec) (p less than .001). We conclude that striking disturbances in VO2 kinetics occur in patients with cyanotic congenital heart disease and that these measurements provide a useful noninvasive means of evaluating the degree to which the increase in pulmonary blood flow is constrained in response to exercise.     

Granulomatous hepatitis associated with glyburide

Summary A wide variety of diseases and injuries can cause granulomatous hepatitis, and drug-induced granulomatous hepatitis is a well-described entity. Sulfonylurea derivatives, which are commonly used oral hypoglycemic agents in the treatment of non-insulin-dependent diabetes mellitus, have been implicated in liver disease. However, glyburide, a second-generation sulfonylurea and a potent hypoglycemic drug, is considered to have less hepatic side effects than chlorpropamide. It has been reportedly associated with cholestatic jaundice and hepatitis and with hypersensitivity angiitis. A case of necrotizing granuloma has been reported. We present a second case of granulomatous hepatitis occurring in a patient who had been taking glyburide for approximately three years, and we review the literature for glyburide-associated hepatitis.