Magnitude of body-cell-mass depletion and the timing of death from wasting in AIDS

The impact of malnutrition on survival in AIDS was evaluated by examining the magnitude of body-cell-mass depletion as a function of time from death. Body cell mass was estimated as total body-potassium content and determined by whole-body counting. There was progressive depletion of body cell mass as patients neared death. The extrapolated and observed values for body cell mass at death were 54% of normal. Body weight had a similar relationship to death, with a projected body weight at death of 66% of ideal. We conclude that death from wasting in AIDS is related to the magnitude of tissue depletion and is independent of the underlying cause of wasting. The degree of wasting seen in this study is similar to historical reports of semistarvation, with or without associated infections. This observation suggests that successful attempts to maintain body mass could prolong survival in patients with AIDS.

Total parenteral nutrition in the critically ill patient: a meta-analysis

CONTEXT

Nutritional support has become a standard of care for hospitalized patients, but whether total parenteral nutrition (TPN) affects morbidity and mortality is unclear.

OBJECTIVE

To examine the relationship between TPN and complication and mortality rates in critically ill patients.

DATA SOURCES

Computerized search of published research on MEDLINE from 1980 to 1998, personal files, and review of relevant reference lists.

STUDY SELECTION

We reviewed 210 titles, abstracts, and papers. Primary studies were included if they were randomized clinical trials of critically ill or surgical patients that evaluated the effect of TPN (compared with standard care) on complication and mortality rates. We excluded studies comparing TPN with enteral nutrition.

DATA EXTRACTION

Relevant data were abstracted on the methodology and outcomes of primary studies. Data were abstracted in duplicate, independently.

DATA SYNTHESIS

There were 26 randomized trials of 2211 patients comparing the use of TPN with standard care (usual oral diet plus intravenous dextrose) in surgical and critically ill patients. When the results of these trials were aggregated, TPN had no effect on mortality (risk ratio [RR], 1.03; 95% confidence interval [CI], 0.81-1.31). Patients who received TPN tended to have a lower complication rate, but this result was not statistically significant (RR, 0.84; 95% CI, 0.64-1.09). We examined several a priori hypotheses and found that studies including only malnourished patients were associated with lower complication rates but no difference in mortality when compared with studies of nonmalnourished patients. Studies published since 1989 and studies with a higher methods score showed no treatment effect, while studies published in 1988 or before and studies with a lower methods score demonstrated a significant treatment effect. Complication rates were lower in studies that did not use lipids; however, there was no difference in mortality rates between studies that did not use lipids and those studies that did. Studies limited to critically ill patients demonstrated a significant increase in complication and mortality rates compared with studies of surgical patients.

CONCLUSIONS

Total parenteral nutrition does not influence the overall mortality rate of surgical or critically ill patients. It may reduce the complication rate, especially in malnourished patients, but study results are influenced by patient population, use of lipids, methodological quality, and year of publication.

Clarification of risk factors for abdominal operations in patients with hepatic cirrhosis

Celiotomy in cirrhotic patients is reported to bear a high risk of operative morbidity and mortality. We reviewed 100 consecutive, cirrhotic patients who underwent nonshunt celiotomy. Thirty patients died and major complications occurred in another 30 patients. Hospital mortality rate was 21% in 39 biliary operations, 35% in 26 procedures for peptic ulcer disease, and 55% in nine colectomies . Fifty-two variables were compared between survivors without complication, survivors with complications, and nonsurvivors. A computer-generated, multivariant discriminant analysis yielded an equation predictive of survival. Utilizing coagulation parameters, presence of active infection, and serum albumin, the equation predicted survival with 89% accuracy. In a similar fashion, amount of operative transfusions, absence of postoperative ascites, pulmonary failure, gastrointestinal bleeding, and culture-positive urine predicted survival with 100% accuracy. We conclude that celiotomy in the cirrhotic patient is truly associated with very high morbidity and mortality, and preoperative assessment can predict survival with 89% accuracy.

The malnutrition, inflammation, and atherosclerosis (MIA) syndrome -- the heart of the matter

The majority of patients starting dialysis already have signs of advanced atherosclerosis, and the risk factors for cardiovascular morbidity and mortality seen in patients with end-stage renal disease (ESRD) develop with the disease progression. Therefore, the predialysis period is the ideal time to start therapeutic interventions. Traditional risk factors alone may not adequately predict cardiovascular disease (CVD) outcome in patients with ESRD. Inflammation has been identified as playing a key role in atherosclerotic CVD. Pro-inflammatory cytokines are pivotal to the inflammation that is associated with malnutrition and atherosclerosis in ESRD. Malnutrition may worsen patient outcome by aggravating existing inflammation and heart failure, accelerating atherosclerosis and increasing susceptibility to infection. Atherosclerosis is itself a major risk factor for CVD mortality. Moreover, inflammation is associated with congestive heart failure. Strong associations between malnutrition, inflammation and atherosclerosis in this patient population suggest the presence of a syndrome we have called malnutrition, inflammation, and atherosclerosis (MIA), which is associated with an exceptionally high mortality rate.

Nutritional depletion in relation to respiratory and peripheral skeletal muscle function in out-patients with COPD

Although increasing attention has been paid to nutritional aspects in chronic obstructive pulmonary disease (COPD), limited information is available regarding the prevalence and consequences of nutritional depletion in a random out-patient COPD population. We studied body composition in relation to respiratory and peripheral skeletal muscle function in 72 COPD patients (mean (SD) forced expiratory volume in one second (FEV1) 53 (15) % predicted), who came to the lung function laboratory for routine lung function measurements. Patients were characterized by the degree of body weight loss and fat-free mass depletion. According to this definition, 14% of the group suffered from both loss of body weight and depletion of fat-free mass, whereas 7% had one of these conditions. We found that tissue depletion was concomitant with lower values for respiratory and peripheral skeletal muscle strength (46.0 (27.2) vs 77.1 (29.8) kg), and a significantly lower transfer coefficient for carbon monoxide (KCO 64.9 (16.2) vs 81.9 (24.5) % pred). Stratification by KCO (< 60% vs > 80%) also revealed significantly lower values for fat-free mass and higher values for intrathoracic gas volumes, total lung capacity (TLC) and residual volume (RV) in the group with a KCO < 60% pred. Analysis of covariance, taking fat-free mass as covariate, indicated an independent contribution of KCO on maximal inspiratory mouth pressure (PImax) but not on peripheral skeletal muscle strength. It is concluded that a substantial number of COPD out-patients suffer from nutritional depletion, preferentially affecting peripheral skeletal muscle function.

Plasma lipid profiles in adults after prenatal exposure to the Dutch famine

BACKGROUND

Small body size at birth has been reported to be associated with an atherogenic lipid profile in humans, and animal experiments have shown that undernutrition during pregnancy permanently alters cholesterol metabolism in the offspring. There is no direct evidence in humans that maternal malnutrition during pregnancy affects the lipid profiles of the offspring.

OBJECTIVES

We assessed the effects of maternal malnutrition during specific periods of gestation on plasma lipid profiles in persons aged approximately 50 y.

DESIGN

This was a follow-up study of men and women born at term as singletons in a university hospital in Amsterdam between 1 November 1943 and 28 February 1947 around the time of a severe famine.

RESULTS

Persons exposed to famine in early gestation had a more atherogenic lipid profile than did those who were not exposed to famine in utero. Their LDL-HDL cholesterol ratios were significantly higher (by 13.9%; 95% CI: 2.6-26.4%). Additionally, their plasma HDL-cholesterol and apolipoprotein A concentrations tended to be lower, and their plasma total cholesterol, LDL-cholesterol, and apolipoprotein B concentrations tended to be higher, although these differences were not statistically significant. The effect of famine was independent of size at birth and adult obesity.

CONCLUSIONS

An atherogenic lipid profile might be linked to a transition from poor maternal nutrition in early gestation to adequate nutrition later on. This suggests that maternal malnutrition during early gestation may program lipid metabolism without affecting size at birth.

The role of the microsomal triglygeride transfer protein in abetalipoproteinemia

The microsomal triglyceride transfer protein (MTP) is a dimeric lipid transfer protein consisting of protein disulfide isomerase and a unique 97-kDa subunit. In vitro, MTP accelerates the transport of triglyceride, cholesteryl ester, and phospholipid between membranes. It was recently demonstrated that abetalipoproteinemia, a hereditary disease characterized as an inability to produce chylomicrons and very low-density lipoproteins in the intestine and liver, respectively, results from mutations in the gene encoding the 97-kDa subunit of the microsomal triglyceride transfer protein. Downstream effects resulting from this defect include malnutrition, very low plasma cholesterol and triglyceride levels, altered lipid and protein compositions of membranes and lipoprotein particles, and vitamin deficiencies. Unless treated, abetalipoproteinemic subjects develop gastrointestinal, neurological, ophthalmological, and hematological abnormalities.

THE EFFECT OF FINITE PERIODS OF UNDERNUTRITION AT DIFFERENT AGES ON THE COMPOSITION AND SUBSEQUENT DEVELOPMENT OF THE RAT

In continuation of the work of Widdowson & McCance (1960), previously published in the Proceedings , groups of rats growing rapidly after a high plane of nutrition during suckling were undernourished for 3 weeks so that their weights at 6, 9 and 12 weeks of age were the same as those of rats which had been growing slowly after a lower plane of nutrition during the first 3 weeks of post-natal life. The undernourished rats were then rehabilitated by being given unlimited food. Undernutrition after weaning made progressively less difference to the ability of the rats to make a complete recovery, so that, whereas a low plane of nutrition during suckling produced smaller animals at maturity, and so to a lesser extent did a low plane of nutrition from 3 to 6 weeks, undernutrition from 6 to 9 weeks did not do so. Undernutrition from 3 to 9 weeks, however, did prevent the animals attaining the same size as the controls. Although their weights might be the same at death the size and composition of rats which had grown fast and then been undernourished differed in characteristic ways from those which had grown slowly and steadily all the time. The bones were longer, the testes and stomachs were heavier, the livers, spleens, skins and small intestines were lighter. The chemical findings were in keeping with the anatomical ones.

A review: new thoughts on growth

There is a critical point in development when the size of an animal, arising from its previous plane of nutrition, determines its appetite thereafter, and hence its rate of growth and dimensions at maturity. A small size at this critical time, brought about by undernutrition, is not followed by "catch-up" growth, however liberal the diet. A full diet produces catch-up growth only if the undernutrition, whatever its cause, has occurred after this critical period is over. It can, moreover, only restore a young animal to its percentile channel of growth, and its ability to do this after long periods of undernutrition becomes progressively limited by the animals chronologic age when the catch-up growth became possible.

THE ADRENOCORTICAL RESPONSE TO INSULIN-INDUCED HYPOGLYCAEMIA

The adrenocortical response to stress as shown by an increase of the plasma cortisol concentration during insulin-induced hypoglycaemia has been studied. The response was found to depend upon the degree and duration of the hypoglycaemia and upon the integrity of the entire hypothalamo-pituitary-adrenal axis. Thus, there was no response in subjects in whom the blood sugar did not fall below 40 mg./100 ml., nor in patients with severe hypothalamic or pituitary disorders.

The test was quick and simple to perform and did not require admission to hospital; it would seem to be of considerable value in the investigation of patients with suspected endocrine disease.

Blood pressure response to psychological stressors in adults after prenatal exposure to the Dutch famine

OBJECTIVE

There is increasing evidence that restricted prenatal growth is associated with exaggerated blood pressure responses to stress. We investigated the effect of maternal undernutrition on the adult offspring's stress response.

DESIGN

A historical cohort study.

METHODS

We performed continuous blood pressure and heart rate measurements during a battery of three 5-min physiological stress tests (Stroop test, mirror-drawing test and a public speech task) in 721 men and women, aged 58 years, born as term singletons in Amsterdam at about the time of the Dutch 1944-1945 famine.

RESULTS

During the stress tests, the systolic blood pressure (SBP) rose from baseline by 20 mmHg during the Stroop test, by 30 mmHg during the mirror-drawing test and by 47 mmHg during the public speech task. The SBP and diastolic blood pressure increase during stress was highest among individuals exposed to famine in early gestation compared with unexposed subjects (4 mmHg extra systolic increase, P = 0.04; 1 mmHg diastolic increase, P = 0.1, both adjusted for sex). Exposure during mid and late gestation was not associated with a stress-related increment of blood pressure (P adjusted for sex > 0.6). Correcting for confounders in a multivariable model did not attenuate the association between famine exposure in early gestation and the SBP increment. The heart rate increment was not related to famine exposure during any part of gestation.

CONCLUSION

We found a greater blood pressure increase during stress among individuals exposed to famine in early gestation. Increased stress responsiveness may underlie the known association between coronary heart disease and exposure to famine in early gestation.

Creatinine production, nutrition, and glomerular filtration rate estimation

This study examined the validity and clinical implications of the assumption of the Modification of Diet in Renal Disease Study (MDRD) formula that age, gender, race, and BUN account for creatinine production (CP). The relationships of MDRD GFR, CP, and nutrition were examined in 1074 Dialysis Morbidity and Mortality Study Wave II patients with reported measured creatinine clearances at initiation of dialysis. Age, gender, race, BUN, and serum creatinine (Scr) were used to calculate MDRD GFR. The measured 24-h urinary creatinine was used to estimate CP. In linear regression, Scr positively correlated with CP independent of age, gender, race, and BUN. Compared with the highest CP quartile, the lowest CP quartile had lower creatinine clearance (5.8 +/- 2.9 versus 11.3 +/- 3.4 ml/min, P <.01) despite lower Scr (5.8 +/- 2.6 versus 8.6 +/- 3.1 mg%, P <.01). There was an excellent correlation between the reciprocal of Scr and the MDRD GFR (r = 0.90). As a result, the MDRD GFR was higher in the lowest CP quartile (10.9 +/- 4.6 versus 7.6 +/- 2.4 ml/min, P <.01). Malnutrition (48% versus 26%, P <.01) was more common in the lowest CP quartile. Each 5-ml/min increase in MDRD GFR was associated with 21% higher odds of malnutrition (P = 0.046) in a multivariable logistic regression, which was abolished by controlling for CP. The fundamental assumption of the MDRD formula is invalid in patients with advanced renal failure, and the use of this formula in these patients might introduce biases.

Effects of maternal undernutrition and heavy physical work during pregnancy on birth weight

The study attempted to determine if heavy physical labour by mothers during pregnancy affected fetal growth when such mothers had calorie intakes which were below 70 per cent of WHO/FAO recommended standards. Full term infants of such mothers had a mean birth weight of 3060 +/- 355 (SD) g compared to 3270 +/- 368 SD g for the newborn of less physically active mothers on similar low calorie diets (P less than 0.01). The mothers who engaged in heavy labour had a mean pregnancy weight gain of 3.3 +/- 2.4 (SD) kg, independent of the birth weight of their offspring, compared with 5.9 +/- 3.3 kg for the less active mothers (P less than 0.001). The mothers' weight in early pregnancy had an insignificant influence on birth weights when mothers were on low calorie intakes.

The clinical implications of impaired glucose tolerance

Impaired glucose tolerance (IGT) was introduced in 1979 as an intermediate category covering the grey area between unequivocal diabetes mellitus and risk free more normal glucose tolerance. The IGT group included those at high risk of subsequent development of non-insulin-dependent diabetes mellitus (NIDDM) but low risk of specific diabetic complications. Categorisation of subjects as IGT is hampered by the variability of the oral glucose tolerance test, but even those shown to be IGT only once are at increased risk of developing NIDDM. The relative roles of inheritance, fetal undernutrition, and environmental life style factors (physical inactivity and diet) in the aetiology and pathogenesis of IGT are discussed, with all contributing. The prevalence of IGT in different populations has now been widely studied with values ranging from 2 to 25% in adults. Rates of progression to NIDDM also vary widely from 2 to 14% per year. Risk factors for progression are discussed. IGT also carries an increased risk of development of cardiovascular disease (CVD) and forms part of the "metabolic syndrome". The role of insulin resistance as a common aetiological factor is briefly reviewed. Finally, possible means of treatment of IGT are listed with the intent of delaying the onset of diabetes and CVD, which is of obvious clinical importance.

Electron microscopic observations in alcoholic heart disease

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Reactive nitrogen and human health: acute and long-term implications

Reactive-nitrogen (Nr) has a wide variety of beneficial and detrimental effects on human health. The most important of the beneficial effects are increasing global and regional food supplies and increased nutritional quality of available foods. However, lack of adequate dietary intake of amino acids and proteins is a serious cause of malnutrition when food supplies are inadequate because of poverty, drought, floods, wars, and displacements of people as refugees. There is sufficient, though limited, quantitative data indicating that increased circulation of Nr in the environment is responsible for significant human health effects via other exposure pathways. Nr can lead to harmful health effects from airborne occupational exposures and population-wide indoor and outdoor air pollution exposures to nitrogen dioxide and ozone. Nr can also affect health via water pollution problems, including methemoglobinemia from contaminated ground water, eutrophication causing fish kills and algal blooms that can be toxic to humans, and via global warming. The environmental pollutants stemming from reactive nitrogen are ubiquitous, making it difficult to identify the extent to which Nr exerts a specific health effect. As all populations are susceptible, continued interdisciplinary investigations are needed to determine the extent and nature of the beneficial and harmful effects on human health of nitrogen-related pollutants and their derivatives.

The effect of undernutrition in early life on cell generation in the rat brain

In undernourished rats aged up to 21 days, the DNA synthesis period in dividing cells of the subependymal and external granular layers is consistently and markedly prolonged, while rates of cell production from these layers are only slightly altered. Cell cycle times are unchanged up to the end of the first week of life and prolonged from day 12. The G1 phase is markedly shortened at 1, 6 and 12 days of age. It would appear that, in comparison with controls, disappearance of the external granular layer is delayed, and cell numbers in both germinal layers may be reduced.