Showing papers by "John J. Reilly published in 1994"

Patterns of obesity in boys and girls after treatment for acute lymphoblastic leukaemia

Abstract: The frequency and pattern of obesity in survivors of acute lymphoblastic leukaemia (ALL) was examined in a retrospective analysis of height and weight at zero, two, and four years from diagnosis in 40 children (19 boys and 21 girls). The children had been treated according to the Medical Research Council protocols UKALL VIII and X, both of which included cranial radiotherapy at a dose of 1800 cGy. Body mass index (BMI), determined as weight/height, was used as a measure of fatness. The BMI Z scores were calculated for each patient from standard tables. The ALL group was compared with a control group of 18 age matched children who had received chemotherapy but no radiotherapy. Changes in BMI between diagnosis and two and four years later were analysed by paired t tests. Mean BMI Z scores at diagnosis were similar between ALL boys, ALL girls, and the control group. Two years after diagnosis the ALL group, particularly the girls, showed a significant increase in BMI. By four years BMI had decreased slightly in the ALL boys, but had increased still further in the ALL girls with 57% having BMI Z scores greater than 2. In the control group BMI increased, but not significantly, at two and four years. It is concluded that the obesity seen in patients treated for ALL is more pronounced in girls than boys, and that cranial irradiation is an important factor.

Measuring the body composition of elderly subjects: a comparison of methods

Abstract: There is a paucity of data on differences between methods for the assessment of body composition in elderly subjects. Studies on younger adults suggest that such differences are of some practical significance at the individual level. In the present study the following methods of estimating percentage body fatness (BF%) were compared in healthy elderly men and women (mean age 70 (SD 6) years: densitometry; skinfold thickness; total body water; bioelectrical impedance (BIA) using an age-specific predictive equation and the manufacturers' equation; body mass index (BMI). Though BF% estimates from the various methods tended to be highly correlated with those from densitometry and with each other, differences between methods at the individual level were marked. In particular, the age-specific equations based on BMI and BIA systematically overestimated BF% relative to the other methods. Biases between BF% estimates derived from densitometry, skinfolds, BIA (manufacturers' equation) and total body water were less marked, indicating little evidence of systematic differences between these methods in elderly subjects. Individual differences between methods were slightly greater than those reported in some studies of younger adults, but this may be of little practical significance, and may be considered inevitable in view of variability between and within subjects in the extent to which the underlying assumptions of these two-component methods are met in elderly subjects.

Does weight for height have prognostic significance in children with acute lymphoblastic leukemia

Abstract: Purpose: We tested the hypothesis that weight for height, a simple index of nutritional status, is related to prognosis in childhood acute lymphoblastic leukemia (ALL). Patients and Methods: The study population was composed of 78 children with ALL tested at one U.K. center on the same protocol (UKALL-X). Outcome measures were relapse/no relapse and time to first relapse. Influence of weight for height, expressed as standard deviation scores, was tested using survival analysis in a retrospective design. Results: The weight-for-height standard deviation score had a significant influence on time until first relapse (log ranks test, p = 0.012), with the highest risk of early relapse in children at the lower end of the weight-for-height distribution. Conclusions: The results suggest that weight for height does have an influence on outcome in ALL, but the mechanism is unclear and the finding requires confirmation by larger scale prospective studies.

Is body composition an important variable in the pharmacokinetics of anticancer drugs? A review and suggestions for further research.

Abstract: Variability between individual patients in the therapeutic and toxic effects of anticancer drugs is one of the major problems confronting clinical oncology. Because of the narrowness of the therapeutic window that separates concentrations that are active from those causing unacceptable toxicity, any means to allow optimisation of drug exposure is worthy of consideration. Normalisation of drug dose using body weight or predicted surface area may be of only limited value in producing a consistent clinical outcome [24, 43]. It may be that characteristics other than body size are of prime importance in giving rise to between-patient variability in response. Body composition (body fatness) could be one such characteristic [1, 7i[. The disposition of a number of agents has been studied in obese and non-obese subjects (for reviews see Abernethy and Greenblatt [1] and Cheymol [7]) and certain general conclusions have been drawn from the literature on noncancer drugs. These conclusions are summarised in Table 1. For some drugs the apparent volume of distribution is altered in obese individuals (e.g. prednisolone) [32]. The hydrophilic or lipophilic nature of certain drugs is likely to be at least partially responsible for variation in distribution volume. Oxidative drug biotransformation is in general minimally changed by obesity, but there are significant exceptions (including prednisolone [1]). For a number of drugs, metabolic conjugation has seen shown to increase with increasing body weight [1]. Renal clearance of some agents is increased in obesity (aminoglycosides; procainamide) and this provides another mechanism by which body composition might influence drug pharmacokinetics. Furthermore, pathological changes associated with more severe obesity (e. g. in cardiac or hepatic function) might be

Prediction of body density from skinfold thickness in elderly subjects: are the existing equations valid?

Abstract: In 33 healthy elderly subjects, body density was measured using hydrodensitometry and predicted from the sum of four skinfold thicknesses. In the men, mean measured density was 1.045 kg/l and mean predicted density 1.041 kg/l, with bias and limits of agreement 0.004 (+/- 0.016) kg/l and 95% confidence interval (CI) for the difference 0.001-0.008 kg/l. In the women, mean measured density was 1.012 kg/l and mean predicted density 1.020 kg/l, and 95% CI for the difference was -0.016-0.000 kg/l. The bias was therefore in the opposite direction in women than men, and limits of agreement were wider (-0.008 +/- 0.030 kg/l) in the women. Biases in prediction of density lead to systematic error in estimation of body fatness in elderly subjects, and this systematic error is more likely to be of practical significance in women than men.

Energy intakes of children with cerebral palsy

Abstract: The energy intakes of 13 children [seven girls, six boys, mean age 10 years (s.d. 4; range 4–15 years)] with cerebral palsy attending a residential school were measured by 3-day weighed dietary record. Energy intake averaged 340 kj/kg per day (s.d. 93; range 102–424) which was higher than the group mean estimated energy requirement (271 kj/kg per day, s.d. 70; range 144–395). The mean coefficient of variation for day to day energy intake was 14%, and food energy not consumed (plate waste and food unsuccessfully ingested) averaged 22% of energy intake. Within the group there was little evidence of marked differences in energy intake between different diagnostic types of cerebral palsy or between children of different feeding/eating ability, although the sample size was too small to detect small between-group differences in intake. Energy intake was somewhat higher than that reported in some other studies, but there was no evidence of the unusually high energy intakes which have been reported previously in some groups of children with cerebral palsy.