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PubMed2005

Patients receiving maintenance hemodialysis with low vs high levels of nutritional risk have decreased morbidity.

OBJECTIVE: To compare the demographic and clinical characteristics and outcomes (morbidity) of 442 patients receiving maintenance hemodialysis who are at different levels of nutritional risk. DESIGN: A retrospective, longitudinal, chart review. SETTING/SUBJECTS: An urban, outpatient hemodialysis unit in New York City. Subjects were stratified according to their number of nutritional risk factors: zero to one=low risk, two to three=moderate risk, four to six=high risk. MAIN OUTCOME MEASURES: Mean values for serum albumin <37 g/L, creatinine <884 micromol/L, total cholesterol <4.42 mmol/L, normalized protein nitrogen appearance <0.9 g/kg/day, weight change > -2.5 kg, and body mass index <24. Morbidity indicators were frequency and duration of hospitalizations. STATISTICAL ANALYSES: Descriptive statistics, analysis of variance, and chi 2 analysis were used to summarize data and to analyze mean differences between the groups and differences in categorical variables, respectively. RESULTS: Compared with the high-risk group, the majority of subjects in the low-risk group were younger, male, and did not have diabetes; fewer had two or more comorbidities. The high-risk group had 75% more hospitalizations and spent 195% more days in the hospital than the low-risk group. CONCLUSIONS: Declining values of the nutritional risk factors and higher hospitalization rates were present in the high-risk group. Older subjects, those with diabetes, and those with two or more comorbidities comprised the majority of the high-risk group. More aggressive nutrition counseling and interventions may be needed for high-risk group members to determine if their risk for morbidity could be reduced.

Age Factors↗

PubMed1983

Differentiating characteristics of myocardial nuclei in cardiomyopathy.

Myocardial tissue obtained by endomyocardial biopsy was semiquantitatively evaluated for nuclear and nucleolar characteristics in six groups of patients: patients with normal cardiac function (group 1), doxorubicin-induced cardiomyopathy (group 2), idiopathic cardiomyopathy (group 3), alcoholic cardiomyopathy (group 4), post-viral cardiomyopathy (group 5), and chronic valvular heart disease (group 6). From each patient, ten nuclei containing nucleoli were examined and rated on the basis of the following characteristics: chromatin clumping, number of fibrillar centers per nucleolus, nucleolonemal structure, size of nucleolus, number of nucleoli per nucleus, and stage of nucleolar change. Mean values for the nuclear characteristics in each group were compared with normal values using the unpaired t test. In the doxorubicin treated group there were significantly increased chromatin clumping, decreased fibrillar centers, decreased nucleolonemal structure, and increased numbers of contracted nucleoli (indicating later stage). These changes may be linked to lowered nuclear and nucleolar activity. In the idiopathic and post-viral groups, characteristics were consistent with increased nuclear and nucleolar activity. There were no significant changes from normal in the nucleolar features of either the alcoholic or valvular groups. Further comparisons between groups using one-way analysis of variance and multivariate statistical analysis support the conclusion that there are significant differences in the nuclear and nucleolar characteristics of these groups.

Analysis of Variance↗

PubMedDate not supplied

Variations in psychosocial functioning associated with patterns of progression in cocaine-dependent men.

This study examined the relationship between patterns of progression of cocaine use and psychosocial functioning in a sample of cocaine-dependent men who were veterans. Four patterns of progression were examined: mild-severe, moderate-severe, mild-moderate-severe, and severe only. Analysis of variance and post hoc analysis with Duncan grouping revealed significant differences among cocaine users with different patterns of progression in terms of negativism, problem index for situations involving unpleasant emotions, problem index for situations involving urges, depression, somatic anxiety, and medical problems in the family. However, there were no significant differences on sensation seeking, confidence to resist taking cocaine in different situations, obsessive compulsiveness, somatization, attention deficit, and social adjustment. Cocaine users with a severe-only pattern of progression were significantly more dysfunctional than those with mild-moderate-severe progression in terms of negativism, problem index for situations involving unpleasant emotions, depression, and somatic anxiety. Cocaine users with mild-moderate-severe progression had significantly less somatic anxiety than those with mild-severe progression and had less negativism and a lower problem index for urges than those with moderate-severe progression. Logistic regression analysis revealed unique behavioral variables associated with different patterns of progression. The implications of these findings for treatment are discussed.

Adaptation, Psychological↗

PubMed1986

Microbiology of beef carcasses before and after slaughterline automation.

The bacterial status of beef carcasses at a commercial abattoir was monitored before and after slaughterline automation. Bacterial counts did not differ significantly overall (P greater than 0.05) between the original manual line and the automated line for either morning or afternoon slaughter. On the manual line counts in the morning were lower than those from carcasses slaughtered in the afternoon, but on the automated line there was no difference between morning and afternoon counts. Due to highly significant line X sample site interaction for both morning and afternoon counts, overall differences among sample sites were not found by analysis of variance. However, principal components analysis revealed a significant shift in bacterial contamination among some sites due to slaughterline changes. The incidence of Enterobacteriaceae increased marginally following automation.

Analysis of Variance↗

PubMed2003

Study of the cultivar-composition relationship in Sicilian olive oils by GC, NMR, and statistical methods.

The aim of this research is to find if there is direct evidence relating the fatty acid composition of olive oils to specific cultivars grown within a well-limited geographical region. To group olive oils according to their own cultivars,(13)C high-field nuclear magnetic resonance (NMR) and gas chromatography (GC) were used to analyze 60 extra virgin olive oils from the same Italian region (southwestern Sicily) obtained from four monovarietal cultivars. The (13)C NMR spectrum provides information about glycerol triesters of olive oils, i.e., about the acyl composition of major components and about the fatty acids' positional distribution on the glycerol moiety. GC gives the complete fatty acid profile of olive oil samples. Selection of NMR and GC peaks on the basis of their sensitivity to the different cultivars was performed by using multivariate analysis of variance (MANOVA). Principal component analysis, tree clustering analysis, multidimensional scaling (MDS), and linear discriminant analysis (LDA) were then performed on the MANOVA-selected peaks. Results obtained from (13)C NMR and GC techniques combined with the multivariate statistical procedure are in good agreement and prove the usefulness of fatty acids analysis to group the monovarietal olive oils belonging to the same cultivars. Grouping of olive oils according to their cultivars occurs for particular (13)C resonances all belonging to fatty chains in the sn 1,3 position of the glycerol moiety.

Analysis of Variance↗

PubMed2000

Color and phenolic compounds of a young red wine. Influence of wine-making techniques, storage temperature, and length of storage time.

The purpose of this work was to determine the influence of vinification technique (maceration temperature and clarification method), storage temperature, and length of storage time on the phenolic compounds and color of young red wines. Multivariate analysis of variance and principal component analysis pointed to significant differences among all of the variables according to vinification technique and length of storage time. Storage temperature did not cause significant differences between some of the variables. The best color characteristics were obtained when low-temperature maceration wines were clarified with polyvinylpyrrolidone. Color quality also improved with lower storage temperature.

Analysis of Variance↗

PubMed1989

Genetic analyses of pupation distance in Drosophila melanogaster.

The inheritance of Drosophila melanogaster larval pupation behaviour is investigated in sixteen reciprocal crosses between field collected lines. These lines were made isogenic for the two major autosomes enabling the data to be analyzed using contrast analysis of variance and biometrical genetic analysis. Results of both analyses showed that the trait "pupation distance", the distance larvae pupate from food, fits a simple additive model of inheritance with no dominance. A chromosomal analysis showed that both the second and third chromosomes act additively on pupation distance and that the third pair of chromosomes had a much larger effect than the second. Significant variability exists in the distance D. melanogaster larvae pupate from fruit in nature. This phenotypic variation results from both heritable variation and variation from environmental sources. When the moisture content of the environment surrounding food is modified, gene by environment interactions also contribute to variation in the phenotype. Selective pressures which may act on larval differences in pupation site choice are discussed.

Analysis of Variance↗

PubMed2003

Factors determining the return to normal activity after appendicectomy.

BACKGROUND: The ability of a patient to return to their normal activities is an important outcome of an operation. The present study was designed to identify and rank factors that are important in determining this return to normal activity (RTNA) after appendicectomy. METHODS: Consecutive patients were identified prospectively following appendicectomy at North Shore Hospital between February and April 2000. Data regarding 25 different factors were obtained by a structured patient interview before and after discharge from hospital and by review of the medical records. Statistical analysis involved analysis of variance and logistic regression analysis. RESULTS: There were 98 patients (median age 28, range 15-69 years, male : female ratio 48:50) who had an appendicectomy. An open appendicectomy was performed in 74 patients, a laparoscopic appendicectomy in 22 patients and a laparotomy in two patients. This includes the 16 patients who were converted from laparoscopic to open appendicectomy (conversion rate 42% 16/38). Acute appendicitis was confirmed by histology in 67 (68%) patients. The significant independent variables identified by anova were ranked by logistic regression analysis. The most important determinant for the time to RTNA was what the doctor advised (chi-squared 43.7, P < 0.0001). The other determinants were the physical activity of their primary occupation (chi-squared 21.5, P < 0.017), the need for strong postdischarge analgesia (chi-squared 21.1, P < 0.13), the American Society of Anesthesiologists (ASA) category (chi-squared 13.6, P < 0.018) and the total sick leave obtained (chi-squared 9.6, P < 0.08). CONCLUSION: It has been shown that the most significant factor in determining the RTNA after appendicectomy was the advice given by the doctor, and that this was more important than the surgical approach, pathology, complications, age or occupation of the patient.

Adolescent↗

PubMed2003

Individual patient variation and inter-rater reliability of lower calyceal infundibular width on routine intravenous pyelography.

OBJECTIVE: To standardise infundibular width (IFW) measurement, to determine patient variability, and to determine inter-rater variability on intravenous pyelography (IVP). PATIENTS AND METHODS: Fifty outpatient IVP films were randomly drawn from two hospitals between 1 July 1998 and 31 August 1999, and examined to measure the lower calyceal IFW on the 5, 10 and 20 min films with compression, and after voiding. Kidneys with previous renal surgery, hydronephrosis or renal anatomical anomalies were excluded; in all, 81 kidneys from 50 patients were examined. The IFW was measured at the narrowest point along the infundibulum. All 50 films were then reviewed by two urologists unaware of their origin, to determine the inter-rater reliability of the infundibular measurements. RESULTS: Analysis of variance (anova) with posthoc analysis showed a significant difference in IFW at each phase of the IVP (repeated measures anova, P < 0.001). The mean (95% confidence interval) IFW was greatest on the compression film, at 4.4 (2.6) mm, and least on the postvoid film, at 1.6 (2.1) mm. Overall inter-rater reliability was 0.9780 (intraclass correlation coefficient), and the Pearson correlation between each rater for the IFW at each phase of the IVP was >/= 0.886. CONCLUSIONS: There is wide variability in lower calyceal IFW among the various IVP films in a given study. Thus any predictive value of the IFW must be standardized for the timing and IVP film type (compression, postvoid, etc.). The inter-rater reliability of IFW is high, suggesting that if used correctly it may be more useful in predicting the outcome after shock wave lithotripsy.

Adolescent↗

PubMed2001

Antenatal corticosteroids and placental histology in preterm birth.

To assess the effects of antenatal corticosteroid use on placental histopathology, we have reviewed a database of 463 consecutive non-anomalous singleton liveborns delivered at less than 32 weeks between April 1988 and December 1994, of which 280 received one or more doses of corticosteroids for promotion of fetal lung maturation. Patients were grouped by the number of corticosteroid doses received (analyzed as none, 1, 2 and 3 or more doses). Clinical and demographic factors were recorded prospectively. Placental histopathology was reviewed blinded to clinical factors except gestational age, and 42 distinct placental lesions were examined and scored for severity. Data were analyzed by contingency tables, one-way analysis of variance, and linear regression analysis. Among clinical variables, univariate analysis showed that the number of corticosteroid doses was significantly related to presence of labour prior to delivery, pre-eclampsia, premature rupture of membranes and clinical suspicion or diagnosis of chorioamnionitis. Using linear regression analysis with these clinical variables as confounders, increased number of doses of antenatal corticosteroids was related to increased severity of villous fibrosis and stromal mineralization, and fewer villous infarcts.

Adrenal Cortex Hormones↗

PubMed2006

Health effects of ultraviolet irradiation in asthmatic children's homes.

OBJECTIVE: Centrally installed ultraviolet (UV) irradiation units were investigated to determine the potential health benefits in mold-sensitized asthmatic children. METHODS: Nineteen mold-sensitized asthmatic children 5 to 17 years of age with home central ventilation systems were enrolled in a 28-week double-blinded placebo controlled cross-over trial. Clinical outcome measurements included morning and evening peak expiratory flow rates (PEFR), PEFR variability, change in forced expiratory volume in 1 second (FEV1), change in total rhinoconjunctivitis and asthma symptom scores, change in rhinoconjunctivitis and asthma quality-of-life scores, and total (rescue and controller) medication use from baseline and between time periods. Environmental outcomes included changes in temperature, relative humidity, dew point, and indoor airborne mold and bacterial counts from baseline and between time periods. Analysis of variance (ANOVA) and regression analysis and t test were used to evaluate relationships between environmental exposure(s) and clinical outcome measurements during each study period. RESULTS: Twelve male and seven female children, average age 10.6 years, were enrolled. A statistically significant improvement in PEFR variability in subjects receiving CREON2000 units followed by placebo units was observed (p < 0.05) across both treatment periods. Within group analysis during treatment period 1, a statistically significant improvement in reduction of asthma symptom scores, the number of days with asthma symptoms, total asthma medication use, and PEFR variability were observed in subjects receiving CREON2000 units versus placebo units (p < 0.05). No significant differences were observed between the CREON 2000 and placebo units for other clinical or environmental outcome measurements. CONCLUSIONS: Central UV irradiation was effective at reducing airway hyperresponsiveness manifested as PEFR variability and some clinical symptoms. A larger cohort controlled longitudinal study to validate the clinical health effects of UV irradiation as a primary indoor environmental intervention for allergic asthma is necessary to confirm this finding.

Adolescent↗

PubMed2004

Electromyographic profiles of gait prior to onset of freezing episodes in patients with Parkinson's disease.

Freezing in Parkinson's disease is a severe and disabling problem of unknown aetiology. The aim of this study was to analyse the temporal pattern and the magnitude of the electromyographic activity of the lower limb muscles just before freezing and to compare this with a voluntary stop and ongoing gait. We recruited 11 patients with a mean age of 64.8 years (SD 5.1) and a mean Unified Parkinson Disease Rating Scale (part III--off) score of 29 (SD 7.9). Within a standard 3D gait laboratory setting, surface electromyographic (EMG) data of the tibialis anterior (TA) and gastrocnemius (GS) muscles were collected using a portable EMG module. Patients in the off-phase of the medication cycle performed several trials of normal walking and voluntary stops or were exposed to freezing-provoking circumstances. Filtered EMG signals were rectified, smoothed and expressed as a percentage of the gait cycle. EMG onset was determined using a preset threshold, corrected after visual inspection. The magnitude of EMG was calculated by integrating EMG signals (iEMG) over (real) time. To control for the altered timing of activity, iEMG was also normalized for time (iEMGnormt). Analysis of variance of repeated measures analysis showed that significantly abnormal timing occurred in the TA and GS muscles with overall preserved reciprocity. Before freezing, TA swing activity already started prematurely during the pre-swing phase, whereas it was significantly shortened during the actual swing phase. For the GS muscle, a similar pattern of premature activation and termination was found during the stance phase before a freeze. GS activity also showed prolonged bursts of activity during the swing phase, not present during the normal and stop condition. Total iEMG activity of both TA and GS was significantly reduced during the pre-freezing gait cycles. However, when controlling for the altered duration of the bursts, the average iEMGnormt increased, as did the peak EMG in TA. In GS, iEMGnormt was not different in the three conditions. In conclusion, our data show that a consistent pattern of premature timing of TA and GS activity occurred before freezing, which was interpreted as a disturbance of central gait cycle timing. The total amount of EMG activity was reduced in both lower limb muscles due to the shortened time in which the muscles were active. In contrast to GS, activity in TA showed increased amplitudes of the EMG bursts, indicating a compensation strategy of pulling the leg into swing. The observed changes contribute to insufficient forward progression, deceleration and eventually a breakdown of movement.

Aged↗

PubMed2000

Association between clinical type of diarrhoea and growth of children under 5 years in rural Bangladesh.

BACKGROUND: The role of diarrhoea in the aetiology of growth retardation in young children remains controversial. To evaluate this, a population-based, longitudinal study of young children aged 6-48 months was conducted in Matlab, a rural area of Bangladesh, between May 1988 and April 1989. METHODS: Data obtained from 584 children were examined by one-year (n = 412) and 3-month (n = 1220) growth periods. Each growth period was analysed based on clinical types of diarrhoea, namely, non-diarrhoea, non-dysentery diarrhoea (diarrhoea without blood), and dysentery (diarrhoea with blood). Weight and height gains were compared among the study groups initially by one-way analysis of variance followed by multivariate analysis adjusting for potential confounding variables. RESULTS: Compared to non-diarrhoea and non-dysentery diarrhoea, dysentery was associated with significantly lower annual weight gain (1866 g [P < 0.01] and 1550 g [P < 0.05] versus 1350 g, respectively) and height gain (6.51 cm and 5.87 cm versus 5.27 cm [P < 0.01], respectively). Both 3-month dysentery and non-dysentery intervals were significantly associated with less weight gain compared to non-diarrhoea intervals (490 g and 522 g versus 637 g [P: < 0.05], respectively). Dysentery intervals were also associated with significantly poorer height gain compared to other intervals (2.19 cm versus 2.42 cm [P < 0.05] and 2.46 cm [P < 0.01], respectively). CONCLUSIONS: The growth of young children is strongly influenced by the clinical type of diarrhoea and the impact is dependent on the proportion of dysentery episodes in the total diarrhoeal burden.

Analysis of Variance↗

PubMed2006

The relationship between somatic growth and in vivo esophageal segmental and sphincteric growth in human neonates.

BACKGROUND: Measurement of aerodigestive tract length is an important determinant for accurate placement of esophageal probes and gavage tubes at the desired location. The relationship of esophageal body, upper esophageal sphincter (UES) and lower esophageal sphincter (LES) lengths with somatic growth in neonates is not well understood. OBJECTIVES: Our objectives were to (1) evaluate a relationship between segmental esophageal lengths and somatic growth parameters and (2) ascertain the relationship between segmental esophageal lengths and gestational age (GA) and postmenstrual age (PMA) in preterm and full-term born human neonates. DESIGN/METHODS: One hundred esophageal manometry studies were performed in 75 infants (30-60 weeks PMA) and the high-pressure zones of LES and UES identified. The distance from nares to LES and from nares to UES, esophageal body length, length of UES and LES derived from the manometry studies were correlated with somatic growth parameters. Growth rate of different esophageal segments was also determined in 26 subjects that underwent longitudinal studies. Analysis of variance and linear regression analysis were performed. RESULTS: Seventy-five neonates of 23.0-40.6 weeks gestational age (0.6-4.4 kg) were studied at 29.1-58.6 weeks PMA (1.0-6.4 kg). Significant correlation (P < 0.001) of PMA and physical growth parameters with the growth of nares-LES (R = 0.8), esophageal body length (R = 0.6) and nares-UES (R = 0.4) were noted. Nares-to-LES length increased at a rate of 0.25 cm/wk PMA during 33.0-36.0 weeks of age. CONCLUSIONS: In vivo esophageal segmental lengths correlated strongly with somatic growth parameters and PMA in neonates. We speculate that this approach has many practical applications with the use of esophageal probes and catheters.

Age Factors↗

PubMed2004

The use of a hemoglobin-based oxygen-carrying solution (HBOC-201) for extracorporeal membrane oxygenation in a porcine model with acute respiratory distress syndrome.

OBJECTIVE: To evaluate whether hemoglobin-based oxygen-carrying solution (HBOC)-201 (Biopure) is an effective alternative to donor blood for extracorporeal membrane oxygenation support in a porcine model of acute respiratory distress syndrome (ARDS). DESIGN: Randomized animal clinical trial. SETTING: Animal surgical research laboratory. SUBJECTS: Immature Yorkshire swine were assigned to one of three groups: 1, noninjured animals, donor porcine blood primed circuit; 2, ARDS-injured, HBOC-201 primed circuit; or 3, ARDS-injured, donor blood primed. INTERVENTIONS: ARDS injury was induced in groups 2 and 3 with oleic acid infusion before bypass. All animals were placed on full venoarterial extracorporeal membrane oxygenation support for 8 hrs. MEASUREMENTS AND MAIN RESULTS: Physiologic variables and laboratory samples were measured at baseline and hourly for 8 hrs. Data analysis consisted of repeated-measures analysis of variance with post hoc analysis. We found that 100% of animals survived on extracorporeal membrane oxygenation for the duration of the study period. HBOC-supported animals had comparable oxygen delivery to both donor blood groups. Mean pulmonary artery pressure, heart rate, and lactate concentrations were higher in the injury groups. Blood pressure was mildly increased in HBOC animals (p <.05 vs. control animals). Methemoglobin concentrations in the HBOC group were elevated and increased over time on extracorporeal membrane oxygenation (p <.001). CONCLUSIONS: HBOC-201 appears to be an effective alternative circuit-priming agent for use during extracorporeal membrane oxygenation. HBOC offers the advantages of rapid availability and diminished donor blood cell exposure. The efficacy of HBOC in longer duration bypass, and its associated methemoglobinemia, need to be further investigated.

Analysis of Variance↗

PubMed1999

Vertical height loss: an investigation of four restorative materials opposing enamel.

PURPOSE: The objective of this in vitro investigation was to compare the vertical wear produced by cone-shaped styli of three ceramic restorative materials and a Type III gold alloy opposing flattened human enamel. Vertical wear was measured as enamel height loss, material stylus height loss, and total vertical height loss (the sum of the enamel height loss and the restorative material height loss). MATERIALS AND METHODS: Ten cone-shaped styli were fabricated from each of four restorative materials, which included two machined ceramics, a pressed ceramic, and a Type III gold alloy. To maintain the standardized shape, styli were not polished or glazed. Specimens were subjected to wear in the presence of water for 100,000 cycles at 1.2 Hz under a load of 75 N using a wear simulation device. Enamel wear was evaluated by profilometry, and stylus wear was evaluated by computer imaging. Vertical wear was reported as enamel height loss, material stylus height loss, and total vertical height loss (the sum of the enamel height loss and material height loss). Data were compared using one-way analysis of variance and Scheffe's analysis (alpha = 0.05). RESULTS: Significant differences existed among materials based on material height loss (p = .0001), enamel height loss (p = .0001), and total vertical height loss (p = .0118). No significant difference among the three ceramics was found in mean total height loss, which ranged from 0.280 to 0.305 mm. However, the Type III gold exhibited less mean total wear (0.231 +/- 0.082) than the pressed and one machineable ceramic. This machined ceramic exhibited the most material height loss (0.249 +/- 0.044 mm). With the other ceramics, mean enamel wear was significantly more (0.211 and 0.216 mm, respectively). CONCLUSIONS: During wear simulation, pressed or machineable ceramics opposing flattened enamel exhibited a similar degree of total vertical height loss. One machined ceramic material wore significantly more than the other materials. The other machineable ceramic and the pressed ceramic wore the opposing enamel significantly more.

Aluminum Silicates↗

PubMed1996

Over-the-counter pharmaceuticals: exploratory research of consumer preference toward solid oral dosage forms.

The capsule dosage form in nonprescription pharmaceuticals persists as being one of the most vulnerable to product tampering. This study examines consumer preference toward three solid oral dosage forms (capsules, caplets, and tablets) in nonprescription products. Thirteen independent variables representing dosage form attributes are measured on semantic differential scales. The data are analyzed using analysis of variance (ANOVA) and factor analysis. Implications for the pharmaceutical marketer are noted. Future directions for research are also outlined.

Administration, Oral↗

PubMed2001

Postnatal malnutrition and growth retardation: an inevitable consequence of current recommendations in preterm infants?

BACKGROUND: Nutrient intakes meeting recommended dietary intakes (RDIs) take time to establish and once established are rarely maintained throughout hospital stay in preterm infants. A nutrient deficit, therefore, accrues. RDI are based on needs for maintenance and growth, with no provision to replace this deficit. We, therefore, hypothesized that postnatal malnutrition and growth retardation were inevitable in infants fed current RDI. METHODOLOGY: Dietary intakes were prospectively collected, by a single observer (N.P.), on a daily basis in a group of preterm infants (n = 105; birth weight </=1750 g; gestational age </=34 weeks) admitted to neonatal intensive care unit over a 6-month period. Actual was subtracted from recommended energy (120 kcal/kg/day) and protein (3 g/kg/day) intakes and nutritional deficits calculated. Infants were weighed on admission and throughout hospital stay. The data were analyzed using a combination of repeated measures analysis of variance and stepwise regression analysis. RESULTS: Nutrient intakes meeting current RDIs were rarely achieved during early life. By the end of the first week, cumulative energy and protein deficits were 406 +/- 92 and 335 +/- 86 kcal/kg and 14 +/- 3 and 12 +/- 4 g/kg in infants </=30 and those at >/=31 weeks. By the end of the fifth week, cumulative energy and protein deficits were 813 +/- 542 and 382 +/- 263 kcal/kg and 23 +/- 12 and 13 +/- 15 g/kg and the z scores were -1.14 +/-.6 and -.82 +/-.5 for infants at </=30 and >/=31 weeks. Stepwise regression analysis indicated that variation in dietary intake accounted for 45% of the variation in changes in z score. CONCLUSIONS: Preterm infants inevitably accumulate a significant nutrient deficit in the first few weeks of life that will not be replaced when current RDIs are fed. This deficit can be directly related to subsequent postnatal growth retardation.postnatal growth retardation, preterm infants.

Analysis of Variance↗