Haematological changes and iron status in teenage girls with eating disorders and weight loss-the importance of menstrual status

AIM: To study haematological changes and iron stores in teenage girls with eating disorders and weight loss. METHODS: Blood haemoglobin concentration, white blood cell and thrombocyte count and serum ferritin concentration were measured at assessments of 446 subjects. RESULTS: Haemoglobin concentrations, leukocyte and thrombocyte counts were related to weight and rate of weight loss but were largely within reference ranges. Serum ferritin concentrations were high in girls with amenorrhea and related to weight and rate of weight loss. Girls who retained menstruations had low serum ferritin concentrations and 37% had depleted iron stores (serum ferritin<16 microg/L). CONCLUSION: Anaemia, leukopenia and thrombocytopenia are uncommon in teenage girls with eating disorders and weight loss. When present, other diseases causing haematological changes should be considered. In amenorrhoic girls muscle catabolism increases serum ferritin concentrations which may give a false impression of an adequate iron status. This is unmasked in girls with retained menstruations who often have depleted iron stores.     

The role of insulin like growth factor (IGF) — 1 and IGF — binding protein-3 in diagnosis of Growth Hormone Deficiency in short stature children

Objective  The purpose of this study was to evaluate the role of IGF-1 and IGFBP-3 in diagnosis of short stature children and adolescents in whom Growth Hormone Deficiency (GHD) was found. Methods  In this cross sectional study the referred short stature children and adolescents to Namazi Hospital in Shiraz- Iran, in 2003–2005 were studied. The inclusion criteria were proved short stature based on the physical examination, weight, height, standard deviation score (SDS) of height < −2, with considering stage of puberty and predicted height in children without any genetic or chronic disorders. The exclusion criteria were any positive physical or laboratory data suggesting hypothyroidism, rickets or liver disorders. For all patients a provocative growth hormone test was performed with propranolol and L-dopa and serum IGF-1 and IGFBP-3 were measured. GHD defined as peak(cutoff) serum GH level under 10 ìg/L and low IGF-1 and IGFBP-3 considered as cutoff serum level under −2 standard deviation. Results  Eighty one short stature patients (39 boys and 42 girls) with mean age of 10.6 ± 3.5 years completed the study. Seventeen patients with GHD were found and in 18 patients IGF-1 level were low. Only in 6 patients both GH and IGF-1 were low and 2 of them had low IGFBP-3. There were no correlations between the levels of GH,IGF-1 and IGFBP-3 in children with short stature due to GHD. The sensitivity and specifity of IGF-1 and IGFBP-3 in assessment of GHD were 35% and 81% for IGF-1 and 12% and 94% for IGFBP-3, respectively. Conclusion  No correlations were found between GH level and serum levels of IGF-1 and IGFBP-3 in short patients and the sensitivity of those tests in assessment of GHD were poor.     

Changes in body weight and body mass index (BMI) in teenage girls prior to the onset and diagnosis of an eating disorder

Growth charts from the school health services were used to study weight changes prior to the onset and diagnosis of eating disorders (ED) with weight loss in 122 teenage girls. In these girls menarche started at 12.6 +/- 1.0 y (mean +/- SD), which is the same for the general population. At their maximal premorbid weight, the girls were 14.6 +/- 1.2 y of age and had a higher weight and body mass index (BMI) than the general population, as evidenced by standard deviation scores (SDS) above zero for weight (0.65 +/- 0.95, p < 0.001) and BMI (0.61 +/- 0.94, p < 0.001). Weight gain prior to the onset of weight loss followed two different patterns. Eighty-three (68%) girls tracked upwards through the weight curves to reach their maximal weight, thus putting on weight at a higher rate than expected. Thirty-nine (32%) girls tracked downwards through the weight curves to reach their maximal weight, but did so starting from a weight and BMI at well above average. Conclusions: Weight gain in teenage girls prior to the onset of an ED deviates from that of the general population. Being or becoming heavier and less lean than their peers could influence body image and decisions on dieting, which, in turn, may be the start of the development of an ED in the otherwise predisposed. The deviation from normal tracking patterns prior to the onset of disease also causes problems in diagnostic procedures and in setting treatment targets for weight gain, since "normal" or expected weight becomes more difficult to establish.     

Heart risk associated with weight loss in anorexia nervosa and eating disorders: electrocardiographic changes during the early phase of refeeding

Refeeding syndromes with electrolyte aberrations, heart failure and arrhythmias may complicate the nutritional rehabilitation of emaciated patients with eating disorders. Therefore, electrocardiographic (ECG) changes and changes in serum electrolyte concentrations following refeeding were studied in 37 admissions of 32 teenage girls with eating disorders. On admission they were all on a weight-losing course and weighed 37.0 ± 8.0 kg (mean ± SD) following a weight loss of 14.2 ± 7.2 kg. On ECG recordings there was a prolongation of the QT interval and an increased QT dispersion. Serum concentrations of sodium, potassium and magnesium were with few exceptions normal. Serum concentrations of creatinine were high in relation to the low body weight, indicating protein catabolism. The first 2 wk of refeeding resulted in a weight gain of 1.7 ± 0.2 kg without signs of refeeding syndromes or electrolyte aberrations. QT prolongation and dispersion normalized within the 3 d of refeeding. It is concluded that oral refeeding of patients with eating disorders and weight loss can be performed efficiently and without causing refeeding syndromes. QT pathology, a consequence of acute starvation and a risk factor for cardiac arrhythmias, normalizes within days. In view of the need to balance adequate refeeding and reduction of QT pathology against the risks of refeeding syndromes the start of refeeding of severely emaciated patients is best performed in a hospital setting where monitoring of ECG and serum electrolytes is possible.     

Weight requirements for return of menstruations in teenage girls with eating disorders, weight loss and secondary amenorrhoea

AIM: To investigate the weight requirements for return of menstruation in teenage girls with eating disorders (ED), weight loss and secondary amenorrhoea. METHODS: Growth charts from the school health services and measurements of weight and stature at assessment and during follow-up were obtained for 127 girls with ED, secondary amenorrhoea and subsequent return of menstruation. Measurements were used to estimate weight and body mass index (BMI) before puberty, at menarche, at the highest weight prior to the onset of the ED, at the last menstruation preceding amenorrhoea, at the lowest weight during treatment, and at return of menstruation. RESULTS: Before onset of the ED, the girls were taller, heavier and less lean than the population average as evidenced by standard deviation scores (SDS) for weight, height and BMI above zero. Weight loss started from an average weight of 58.9 +/- 9.8 kg (mean +/- SD), a last menstruation occurred at 51.5 +/- 6.9 kg, the lowest weight during treatment was 45.6 +/- 7.0 kg and menstruation returned at 52.9 +/- 6.0 kg. Return of menstruation occurred within a wide weight range. However, if weight at return of menstruation was expressed in SDS, it could be predicted by a linear regression on weight SDS at loss of menstruation (r2 = 0.76; p < 0.001). CONCLUSIONS: The weight level required for return of menstruation is highly individual but can be predicted by the weight at which menstruations cease. In the treatment of ED, there is a need for such individual weight targets--a target based on the population weight for height and/or age may be too generalized and too low.     

Medical assessment of adolescent girls with eating disorders: an evaluation of symptoms and signs of starvation

AIM: To investigate the prevalence of symptoms and signs related to starvation at the initial examination of adolescent girls with eating disorders (ED). METHODS: Two hundred and eleven girls with eating disorders recruited for a multicentre research and evaluation programme of six specialist eating disorder services in Sweden have been studied. The presence or absence of 12 symptoms, reported by the patients, and 16 signs, observed by the examiners, were registered and related to body weight. RESULTS: Eleven observed signs--loss of subcutaneous fat, loss of muscle mass, loss of muscular force, dry and scaly skin, brittle nails, dry and brittle hair, lanugo hair, resting pulse <60, systolic blood pressure <110, peripheral hypothermia, and peripheral cyanosis--were related to body weight expressed in standard deviation scores (SDS). When the number of observed signs for each patient was calculated, there was a strong relationship with weight. The odds ratio for having more than two signs was 4.35 (95% CI 2.67-7.04; p = 2.8 x 10(-9) for every one-unit change in weight SDS. Of the symptoms reported by the patients, only three were related to weight. When the number of reported symptoms for each patient was calculated, a relationship with weight was not observed. CONCLUSION: In adolescent girls with ED, physical signs observed at medical examination can be related to weight. However, reported symptoms are poorly related to weight and may be influenced by other factors. The finding emphasizes the importance of medical assessment at presentation of patients with ED.     

Clinical onset and diagnosis of eating disorders in premenarcheal girls is preceded by inadequate weight gain and growth retardation

Aim: To study growth and weight changes before the presentation of an eating disorder (ED) with premenarcheal onset. Methods: Growth charts from the school health services were obtained for 45 girls assessed during the period 1990-2000 at Uppsala University Children's Hospital. Measurements of weight and height from the charts and at presentation were recalculated into standard deviation scores (SDS). Results: At their maximal weight the girls were 12.5 ± 1.7 (mean ± SE) y old. They were then lighter, shorter and leaner than the general population mean, as evidenced by SDS below zero for weight (-0.43 ± 1.08; mean ± SD), height (-0.45 ± 1.01) and body mass index (BMI) (-0.35 ± 1.07). At presentation approximately 1 y later they had lost 5.8 ± 4.3 kg and were considerably underweight (weight SDS -2.27 ± 1.33) and further stunted (height SDS -0.76 ± 0.97). The point on the growth curves with the highest SDS for weight was observed at 8.5 ± 1.4 y of age. The girls were then heavier (weight SDS 0.35 ± 0.93) and less lean (BMI SDS 0.42 ± 0.97) than the population average. A tendency to track down through weight and height curves before the onset of weight loss was thus observed. Total weight deficit was as much as 31 ± 10% of expected body weight. Analyses of weight and height deficits indicated that two-thirds of the weight deficit and 60% of the height deficit was generated before the onset of weight loss.

Conclusion: Girls with eating disorders presenting before menarche may have a long history of poor weight gain and growth retardation before the onset of weight loss. This is in contrast to older girls, who commonly start weight loss at an above-average weight without prior poor weight gain. Since the psychopathology of ED in young girls may be different and less evident compared with older teenagers it is important to be aware that poor weight gain and growth retardation may be associated with early-onset ED.     

Time course and determinants of leptin decline during weight loss in obese boys and girls.

OBJECTIVE: To investigate whether changes in leptin concentrations during weight loss can be explained by gender, puberty, baseline adiposity and changes in adiposity, body composition, rate of weight loss, physical activity and insulin concentrations. DESIGN: A longitudinal study with 9 repeated measures during a 12-week weight loss programme. SUBJECTS: Fifty-three boys and 62 girls (7.9-15.2 years) with body mass index (BMI) standard deviation scores (SDS) of median 2.78 and 2.70, respectively. MEASUREMENTS: Height, weight, fat mass percentage assessed by bioimpedance, Tanner stages, testicular size, physical activity scores, blood leptin (ng/ml) and insulin concentrations (pmol/l) were measured at baseline, and except for Tanner stage and testicular size, repeated regularly during the programme. RESULTS: The weight loss was accompanied by a steep decline in leptin concentrations during the first 10-11 days, followed by a less steep decline until day 82. Leptin declined to 39% in boys and 51% in girls of the level that was expected given the relationship at baseline between leptin and BMI SDS, and the BMI SDS changes during weight loss. The biphasic leptin decline was independent of gender, puberty, baseline adiposity or concomitant changes in BMI SDS, fat mass percentage, rate of weight loss, physical activity scores or insulin concentrations. CONCLUSION: The biphasic leptin decline, which exceeded the level expected, was independent of puberty, baseline adiposity and changes in adiposity, body composition, rate of weight loss, physical activity scores and insulin concentrations. The dissociation of the leptin-weight relationship during weight loss may contribute to the general leptin variability in obese subjects.     

Omega-3 essential fatty acid status is improved during nutritional rehabilitation of adolescent girls with eating disorders and weight loss

Aim: Essential fatty acid status is altered in eating disorders with weight loss, and deficiencies in polyunsaturated omega‐3 essential fatty acids have been implicated in the development of depression and other psychopathologies. Presently, recovery of essential fatty status during the treatment of adolescent girls with eating disorders has been investigated. Methods: Fatty acids were analysed in erythrocyte membranes of 24 adolescents girls with eating disorders of short duration, and on the average >10 kg weight loss at presentation. Blood samples were obtained at presentation and following weight recovery on standard diet without supplementation with essential fatty acids. Results: Alterations of essential fatty status observed at presentation largely normalized during treatment. Omega‐3 status improved following weight gain. Conclusion: Adequate nutrition, normalization of eating behaviours, weight gain and the consequent return to normalization of metabolism and endocrine function are sufficient to ensure normalization of essential fatty acid status. Supplementation with omega‐3 polyunsaturated fatty acids does not appear warranted.     

Serum leptin concentrations in relation to pubertal development

OBJECTIVES: The amount of adipose tissue influences pubertal development and fertility in girls. A candidate for mediating this is the hormone leptin, derived from adipocytes. This work was carried out to determine whether the leptin concentration in serum is regulated during pubertal development. SUBJECTS AND METHODS: Serum concentrations of leptin were determined by radioimmunoassay in a sample of 252 healthy children representing all pubertal stages. RESULTS: Serum leptin concentrations correlated directly with age (r = 0.53), body mass index (BMI) (r = 0.71), and weight for height SD score (r = 0.44) in girls and with BMI (r = 0.33) and weight for height SD score in boys (r = 0.36). Leptin concentrations increased with pubertal development in girls, resulting in significantly higher concentrations at pubertal stages 4 and 5 than at the prepubertal stage, whereas there was no change in the boys. CONCLUSIONS: Serum leptin concentrations increased during pubertal development in the girls, but remained constant in the boys. Whether the increase in serum leptin concentrations in girls is of importance for, or a consequence of, pubertal development is still to be determined.     

Serum leptin concentrations in children with mild-to-moderate protein-energy malnutrition

BACKGROUND: The aim of the present study was to clarify the relationship between nutritional anthropometric parameters and serum leptin concentrations in otherwise healthy children with mild-to-moderate protein-energy malnutrition (PEM) secondary to inadequate energy intake. METHODS: Eighty-one otherwise healthy children with poor appetite and inadequate energy intake were enrolled in the study. The anthropometric values were evaluated in all subjects. Fasting serum leptin concentrations were assessed. RESULTS: Of the 81 otherwise healthy children, 30 were found to have mild-to-moderate PEM. The control group consisted of 51 healthy children who had normal anthropometric values, even though they had inadequate energy intake. There was a significant difference in serum leptin concentrations between the two groups (P < 0.01). Furthermore, there was a positive correlation between mean serum leptin concentrations and percentage of standard weight for height in the patient and the control group (P < 0.05). Multiple linear regression analysis indicated that percentage of standard BMI was the best predictor for serum leptin concentrations (P < 0.05). CONCLUSION: In addition to BMI, percentage of standard weight for height is a valuable nutritional anthropometric parameter for serum leptin concentrations in PEM and inadequate energy intake. However in the present study, percentage of standard BMI was the best predictor for serum leptin concentrations. Serum leptin concentrations are low not only in severe PEM, but also in children with mild-to-moderate PEM without chronic disease.     

Monitoring nutritional status accurately and reliably in adolescents with anorexia nervosa

Aim:   Accurate assessment of nutritional status is a vital aspect of caring for individuals with anorexia nervosa (AN) and body mass index (BMI) is considered an appropriate and easy to use tool. Because of the intense fear of weight gain, some individuals may attempt to mislead the physician. Mid-upper arm circumference (MUAC) is a simple, objective method of assessing nutritional status. The setting is an eating disorders clinic in a tertiary paediatric hospital in Western Australia. The aim of this study is to evaluate how well MUAC correlates with BMI in adolescents with AN.
Methods:   Prospective observational study to evaluate nutritional status in adolescents with AN.
Results:   Fifty-five adolescents aged 12–17 years with AN were assessed between January 1, 2004 and January 1, 2006. MUAC was highly correlated with BMI ( r  = 0.79, P  < 0.001) and individuals with MUAC ≥20 cm rarely required hospitalisation (negative predictive value 93%).
Conclusions:   MUAC reflects nutritional status as defined by BMI in adolescents with AN. Lack of consistency between longitudinal measurements of BMI and MUAC should be viewed suspiciously and prompt a more detailed nutritional assessment.     

中枢性性早熟女童血清性激素结合蛋白水平的变化

目的 观察中枢性性早熟(CPP)女童血清性激素结合蛋白(SHBG)水平变化及其与体质量指数(BMI)和稳态模型胰岛素抵抗指数(HOMA-IR)等的相关性.方法 以41例CPP(CPP组)、33例部分性乳房早发育(PT组)和30例健康体检(健康对照组)的青春期前女童为研究对象,进行生长发育评价,检测其血清SHBG水平.分析血清SHBG水平与BMI、胰岛素样生长因子-1(IGF-1)、骨龄(BA)和HOMA-IR的关系.采用SPSS 10.0软件进行统计学分析.结果 CPP组血清SHBG水平明显低于PT组和健康对照组,血清IGF-1水平则高于PT组和健康对照组;但PT组SHBG和IGF-1水平与健康对照组比较均无统计学差异;HOMA-IR在3组间比较也无统计学差异.同时,经双变量之间的相关分析,发现血清SHBG水平与HOMA-IR呈负相关(r=-0.27,P=0.01),与BMI亦呈明显负相关(r=-0.41,P=0.00),而与BA和IGF-1均无相关性.结论 CPP女童血清SHBG水平明显降低,可能存在着潜在的高雄激素血症.     

Heart risk associated with weight loss in anorexia nervosa and eating disorders: risk factors for QTc interval prolongation and dispersion

Risk factors for QTc interval prolongation and dispersion, indicators of an increased risk for cardiac arrhythmia and sudden death, have been investigated in patients with eating disorders (ED) and ongoing weight loss. Patients were characterized with regard to weight, body mass index (BMI; weight/length2), duration of weight loss, rate of weight loss and rate of weight loss immediately preceding examination. At examination, a 12-lead electrocardiographic (ECG) registration and blood samples for analysis of serum electrolytes were obtained. In total, 92 examinations in 58 female patients aged 15.5+/-1.7 (mean +/- SD) y were analysed. Control ECG recordings were obtained from 38 normal-weight teenage girls with no known heart disease. Patients with ED weighed 40.7+/-7.8 kg, corresponding to BMI 15.2+/-2.4 kg/m2 following a weight loss of 11.8+/-6.5 kg. In ED patients, the ECG showed bradycardia, a shift to the right of the QRS axis, diminished amplitudes of the QRS complex and T wave, and prolongation and increased dispersion of the QTc interval. In multiple regression analyses low weight, low BMI and rapid weight loss immediately preceding the examination were the most important independent predictors of QTc interval prolongation and dispersion. It is concluded that an ECG examination is an important part of the assessment of patients with ED and ongoing weight loss, even in the absence of electrolyte disturbances, and especially if the patient is severely underweight or weight loss is rapid.     

Long‐term effects of rapid weight gain in children,adolescents and young adults with appropriate birth weight for gestational age: the kiel obesity prevention study

Aim: This study investigates the effect of rapid weight gain in term children, adolescents and young adults born appropriate for gestational age. Methods: In all, 173 girls and 178 boys aged 6.1–19.9 (12.5 ± 3.1)years participated. Rapid weight gain (group 1) was defined as a change in weight‐SDS (standard deviation score) from birth till two years >0.67, ‘no change’ as ≥?0.67 and ≤0.67 (group 2) vs ‘slow weight gain’ as 90th age‐/sex‐specific BMI‐percentile was defined as overweight. Parental BMI, socio‐economic status and lifestyle were assessed as confounders. Results: A total of 22.8% gained weight rapidly, and 15.7% was overweight. Group 1 compared with group 2 and 3 subjects was taller, heavier and had a higher prevalence of overweight (girls/boys: 26.2%/28.9% vs 11.6%/19.0% vs 2.8%/5.0%; p < 0.01/p < 0.05). Concomitantly, a higher WC, %FM and FFM were observed. Rapid weight gain was positively associated with REE (adjusted for FFM) in boys (r = 0.26; p < 0.01), but not with cardio‐metabolic risk factors. Conclusion: Rapid weight gain was related to increases in height, weight, a higher prevalence of overweight and central fat distribution. In addition, rapid weight gain was related to a higher REE in boys, but not to cardio‐metabolic risk factors.     

Clinical measures of adiposity and percentage fat loss: which measure most accurately reflects fat loss and what should we aim for?

OBJECTIVE: To determine which clinical measure of childhood obesity should be monitored to best reflect change in adiposity in a weight management programme and estimate the degree of change needed to be relatively certain of fat reduction. SUBJECTS: 92 obese children with a mean (range) age of 12.8 (6.9-18.9) years and a mean body mass index standard deviation score (BMI SDS) of +3.38 (+2.27 to +4.47) attending a hospital-based clinic on a regular, 3 monthly basis. Measurements: Pairs of weight and height measured up to 2.41 years apart used to derive BMI as kg/m2, and adjusted for age and gender to give weight and BMI SDS (BMI-z score) using British 1990 Growth Reference Data. Contemporaneous adiposity estimated by fatness measured by a bioimpedance segmental body composition analyser. RESULTS: Changes in BMI-z scores, compared to BMI, weight and weight SDS, most accurately reflected loss of fat. Reductions of 0.25, 0.5, 0.75, and 1 BMI SDS equate to expected mean falls in total body fat percentage of 2.9%, 5.8%, 8.7% and 11.6%. Approximate 95% prediction intervals indicated that a fall in BMI SDS of at least 0.6 over 6-12 months (or 0.5 over 0-6 months) is consistent with actual fat loss. CONCLUSION: Change in BMI-z score best reflects percentage fat loss compared to BMI, weight and weight SDS. The wide variation in likely percentage fat loss for a given BMI SDS reduction means a loss of 0.5-0.6 is required to be relatively certain of definite percentage fat reduction.     

Prevalence of protein-energy malnutrition at diagnosis in children with acute lymphoblastic leukemia.

BACKGROUND: The purpose of the present study was to test the hypothesis that protein-energy undernutrition is common in patients with acute lymphoblastic leukemia at diagnosis. Previous studies have failed to establish whether undernutrition is a common feature at diagnosis. METHODS: Body mass index (BMI, weight/height2), expressed as a standard deviation score (SDS) relative to contemporary United Kingdom reference data, was used as the index of nutritional status. The index was calculated in a national cohort of standard-risk patients (n = 1019) treated in the same protocol in the United Kingdom. RESULTS: Prevalence of undernutrition (defined as BMI SDS <-2.0) exceeded expected frequencies in boys (7.6%) and girls (6.7%). These differences were statistically significant (p < 0.001), with a 95% confidence interval for the prevalence of undernutrition of 5.8% to 9.0%. CONCLUSIONS: Undernutrition is relatively common in patients with newly diagnosed acute lymphoblastic leukemia, with a threefold excess of patients below the cutoff used to define undernutrition. Screening for undernutrition at diagnosis of acute lymphoblastic leukemia is indicated, and the BMI SDS is a simple index of nutritional status that could be readily calculated using measurements routinely made at diagnosis. The same simple screening technique could also be used clinically to detect and manage or prevent overnutrition (obesity), which is common in these patients after diagnosis.     

Relation between serum insulinlike growth factor-1, insulinlike growth factor binding protein-2, and insulinlike growth factor binding protein-3 and nutritional intake in premature infants with bronchopulmonary dysplasia.

BACKGROUND: The usefulness of serum insulinlike growth factor (IGF)-system-peptide measurement to assess the adequacy of nutritional intake in premature infants with chronic lung disease bronchopulmonary dysplasia (BPD) was assessed. METHODS: Twenty-nine premature infants had serial measurements taken of their serum IGF-1, insulinlike growth factor binding protein (IGFBP)-2, and IGFBP-3 concentrations between 2 and 6 weeks of age. Regression analyses were used to examine the relation between nutritional parameters and IGF-1, IGFBP-2, and IGFBP-3 concentrations in premature infants with and without BPD. RESULTS: The group of infants with BPD (n = 12) did not differ from infants without BPD (n = 17) in gestational age or weight at entry, but gained less weight during the study period. In infants without BPD, IGF-1 correlated positively with protein intake (r = 0.50) and caloric intake (r = 0.41) over the 3 days before sample collection and with weight change over the previous week (r = 0.46). In contrast, infants with BPD showed a significant correlation between IGF-1 and weight change (r = 0.54) only. There was a significant negative correlation between IGFBP-2 and protein intake in infants without BPD (r = -0.50) and in infants with BPD (r = -0.41). Negative correlations between IGFBP-2 and both weight change (r = -0.64) and caloric intake (r = -0.43) over the previous week were found only in the group of infants without BPD. IGFBP-3 correlated positively with weight changes and protein intake in both groups but correlated with caloric intake only in the group without BPD. Multiple regression analyses were used to determine significant independent variables associated with IGF-1, IGFBP-2, and IGFBP-3. In infants without BPD, significant independent predictors of IGFBP-2 were 7-day weight change and 2-day protein intake; 3-day caloric intake was the only significant independent predictor for IGFBP-3. For infants with BPD, 3-day weight gain was the only independent variable associated with serum IGF-1. Protein intake in the week before sample collection was an independent predictor of IGFBP-2 and 3-day weight change and 2-day protein intake were independent predictors of IGFBP-3. CONCLUSIONS: These results confirm that changes in serum IGF-1, IGFBP-2, and IGFBP-3 reflect the nutritional status of premature infants and demonstrate that the relation between these proteins and nutritional intake differs in premature infants with and without BPD. Refinement of these observations by future studies may permit a more accurate determination of the protein and caloric intake sufficient for growth and repair after injury in premature infants with lung disease.     

Essential fatty acid status in teenage girls with eating disorders and weight loss

Aim: To explore the relationship between essential fatty acids (FA) and weight changes in adolescent girls with eating disorders (ED). Methods: Blood samples were obtained from 220 girls with ED and 39 healthy controls. The girls with ED were 15.3 ± 1.5 years of age and weighed 49.8 ± 8.7 kg (BMI 18.3 ± 2.8 kg/m²) after a weight loss of 6.8 ± 6.4 kg. FA were analysed in plasma phospholipids (PPL) and erythrocyte membranes (ERY). Results: The proportions of saturated and monounsaturated FA were increased during weight loss, while linoleic acid (18:2ω6) was decreased. The proportions of eicosapentanoic acid (EPA) (20:5ω3) and docosahexanoic acid (DHA) (22:6ω3) in PPL and ERY did not differ from controls. The activity of stearoyl‐CoA‐desaturase was increased as evidenced by an increased product/precursor ratio and correlated with the rate of weight loss. The activities of delta‐6‐desaturase and delta‐5‐desaturase did not differ from controls. The rate of weight loss was inversely correlated with delta‐6‐desaturase and directly correlated with delta‐5‐desaturase. Conclusion: The FA profile indicates low‐fat intake, fat mobilization from stores and an increased conversion of essential FA at the delta‐5‐desaturase step during weight loss in adolescent girls with ED. Normal levels of EPA and DHA were maintained.     

Update of nutrition guidelines for the teen: trends and concerns

Sociocultural influences are known to affect adolescent eating patterns and behaviors. Some teens reject a meat-based diet to become vegetarians; others take up dieting to lose weight or develop an eating disorder. Teens require increased nutrients to provide for the accelerated growth that takes place during these years. Nutritional deficiencies in adolescence can lead to loss of height, osteoporosis, and delayed sexual maturation. Sports also play an important role in many teens' lives. The desire to excel can lead to increased training and prolonged periods of dieting. Disordered eating, amenorrhea, and osteoporosis describe the "female athlete triad." Although more frequently seen in girls, boys who participate in sports that have an emphasis on size and weight such as wrestling and body building are also at risk for subclinical eating disorders. This paper discusses issues surrounding restrictive and nonrestrictive food patterns of adolescents and their nutritional consequences.