liu.seSearch for publications in DiVA
Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • oxford
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Studies on adipose tissue, body fat, body water and energy expenditure during the first four months of infancy using magnetic resonance imaging, skinfold measurements and the doubly labelled water method
Linköping University, Department of Molecular and Clinical Medicine, Pediatrics. Linköping University, Faculty of Health Sciences.
2003 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

During recent years much interest has been focused on the relationship between early nutrition and the future health of humans. Poor growth during early life has been associated with impaired glucose tolerance and coronary heart disease later in life, while rapid weight gain in infancy has been associated with an increased risk of obesity during childhood. Access to appropriate methods that can provide information about adipose tissue (AT), total body fat (TBF), and total energy expenditure (TEE) during infancy is important in order to conduct successful research in this area. The magnetic resonance imaging (MRI) technique based on the combination of a magnetic field and radiowaves can provide images of the body by which total adipose tissue volume (ATV) as well as its distribution between subcutaneous and non-subcutaneous ATV can be assessed. The doubly labelled water (DLW) method can assess total body water (TBW) and TEE. Estimates ofTBW can be used to calculate TBF. Measurements ofskinfold thickness (SFT) represent a traditional technique for assessing body fatness in humans, but even though it is simple in concept and easily applied, it has so far not been evaluated in infants under four months of age. The combination of the MRI and DLW methods represents a new possibility-to evaluate estimates of TBF based on measurements of SFT and to study various aspects of body composition during infancy. A method based on MRI which can assess total, subcutaneous and non-subcutaneous ATV was therefore developed, evaluated and applied in studies of infants.

Total, subcutaneous and non-subcutaneous ATV was assessed in 46 fullterm infants between four and 131 days old (25 boys and 21 girls), and in eight moderately preterm infants (six boys and two girls) with a postnatal age of 44-75 days. The infants were also studied by means of the DLW method to assess TBW and TEE, while TBF and the degree of hydration in fat free weight (FFW) and AT fat content were calculated. TBF based on SFT measurements was also assessed in 43 of these infants.

The MRI method can assess total ATV with good precision and with relative validity. During the first four months of life a considerable gain in ATV was found in both boys and girls. About 90% of the adipose tissue was located subcutaneously. Based on estimates of ATV and TBW, changes in body fat, FFW and in the degree of hydration in FFW were found to be similar to classical reference data for early infancy. During the first four months of life a significant increase in TEE (kJ/kg/24h) with age was found, probably an effect of a gradual increase in physical activity. In preterm infants at term postconceptional age and in fullterm newboms, the ATV (ml/kg body weight), TBW (%), the fat content in AT as well as the proportion of total ATV present as subcutaneous ATV were similar, while TEE (kJ/kg/24h) was 20% higher in the preterm infants than in the fullterm newboms. This difference could be explained by more rapid growth and also by higher physical activity in the preterm infants. Estimates of TBF based on SFT produces biased estimates of body fat in fullterm infants under four months of age. This bias can to a large extent be explained by a considerable variation in the fat content of AT. However, estimates of TBF obtained by means of the SFT method can be used to estimate body fatness in groups of infants with similar AT fat content.

In conclusion, estimates of ATV obtained by means of MRI contributed to new knowledge regarding various aspects of body composition during infancy.

Place, publisher, year, edition, pages
Linköping: Linköpings universitet , 2003. , 72 p.
Series
Linköping University Medical Dissertations, ISSN 0345-0082 ; 798
National Category
Medical and Health Sciences
Identifiers
URN: urn:nbn:se:liu:diva-25697Local ID: 10073ISBN: 91-7373-488-8 (print)OAI: oai:DiVA.org:liu-25697DiVA: diva2:246245
Public defence
2003-09-12, Aulan, Hälsans Hus, Hälsouniversitet, Linköping, 09:00 (Swedish)
Opponent
Available from: 2009-10-08 Created: 2009-10-08 Last updated: 2012-10-10Bibliographically approved
List of papers
1. Description and evaluation of a method based on magnetic resonance imaging to estimate adipose tissue volume and total body fat in infants
Open this publication in new window or tab >>Description and evaluation of a method based on magnetic resonance imaging to estimate adipose tissue volume and total body fat in infants
1998 (English)In: Pediatric Research, ISSN 0031-3998, E-ISSN 1530-0447, Vol. 44, no 4, 572-577 p.Article in journal (Refereed) Published
Abstract [en]

Information about body fatness is important during nutritional assessment of infants, but current methods to estimate body composition in vivo are often not applicable in infants. Therefore, a new method based on magnetic resonance imaging (MRI) was developed. This method, which can assess the volume and distribution of adipose tissue (AT) as well as total body fat, was applied in 11 healthy full-term infants. Their total body water was also estimated using the isotope dilution technique. Adipose tissue volume (ATV) was calculated from AT area in 16 images of the body taken by an MRI scanner (1.5 tesla). AT area was assessed using a computer program in which AT criteria was defined by the observer. ATV of the infants was therefore evaluated once by three observers and twice by a fourth observer. The different observers estimated total, s.c., and non-s.c. ATV with a precision that varied between 1.9 and 7.2%, 2.0 and 4.8%, and 4.2 and 40.7%, respectively. Variations during AT area calculations accounted for a large part of the imprecision when assessing total and s.c. ATV. The linear relationship between percent total body water and total ATV in relation to body weight was significant in all evaluations. Although average total ATV varied when estimated by the four observers, there was, within each evaluation, a fairly constant order between infants with respect to their ATV. It is concluded that the MRI procedure represents a useful possibility to assess body fatness in infants.

National Category
Medical and Health Sciences
Identifiers
urn:nbn:se:liu:diva-84497 (URN)10.1203/00006450-199810000-00017 (DOI)
Available from: 2012-10-10 Created: 2012-10-10 Last updated: 2017-12-07Bibliographically approved
2. Studies on human body composition during the first 4 months of life using magnetic resonance imaging and isotope dilution
Open this publication in new window or tab >>Studies on human body composition during the first 4 months of life using magnetic resonance imaging and isotope dilution
2003 (English)In: Pediatric Research, ISSN 0031-3998, E-ISSN 1530-0447, Vol. 54, no 6, 906-912 p.Article in journal (Refereed) Published
Abstract [en]

Assessing body composition during infancy requires data for the so-called reference infant. Currently available data for this purpose need to be updated and extended using methods based on principles different from those used previously to define the reference infant. Thus, magnetic resonance imaging was applied to full-term healthy boys (n = 25) and girls (n = 21), 4-131 d old, to estimate adipose tissue volume (ATV) and the amounts of s.c. and non-s.c. adipose tissue (AT). Total body water was estimated using isotope dilution. Total body fat (TBF), fat free weight (FFW) and the degree of hydration in FFW were calculated. Increases in weight, TBF, and FFW with age agreed with current reference data, although when compared with the reference, a slightly more rapid increase in % TBF was observed for boys. The degree of hydration in FFW was 78.9 ± 4.5% (n = 45). Both sexes showed significant increases with age in s.c. ATV (14.7 and 13.0 mL/d for boys and girls, respectively) and in non-s.c. ATV (1.58 and 1.26 mL/d, respectively). Subcutaneous ATV was 90.5 ± 1.8% (boys) and 91.1 ± 1,9% (girls) of total ATV. In conclusion, a pronounced increase with age in the amount of AT was demonstrated involving a considerable gain in s.c. fat during early life. Except for % TBF in boys, changes in body composition with age agreed with current reference data.

National Category
Medical and Health Sciences
Identifiers
urn:nbn:se:liu:diva-46416 (URN)10.1203/01.PDR.0000088064.63106.5E (DOI)
Available from: 2009-10-11 Created: 2009-10-11 Last updated: 2012-10-10Bibliographically approved
3. Total energy expenditure, body composition and weight gain in moderately preterm and full-term infants at term postconceptional age
Open this publication in new window or tab >>Total energy expenditure, body composition and weight gain in moderately preterm and full-term infants at term postconceptional age
2003 (English)In: Acta Paediatrica, ISSN 0803-5253, E-ISSN 1651-2227, Vol. 92, no 11, 1327-1334 p.Article in journal (Refereed) Published
Abstract [en]

Aim: To assess total energy expenditure (TEE) and body composition, i.e. total body water (TBW) and adipose tissue volume (ATV), at term age in 8 healthy preterm infants, born between gestational weeks 30 and 33, and in 9 healthy full-term newborns.

Methods: Total and subcutaneous ATVs were assessed using magnetic resonance imaging, while TEE and TBW were estimated using doubly labelled water.

Results: Total ATV was 272 ±21 and 261 ± 56 ml/kg body weight, while subcutaneous ATV was 88.9 ± 1.6 and 89.7 ± 2.0% of total ATV for preterm and full-term infants, respectively. The corresponding figures for TBW (as percentage of body weight) were 67.4 ± 2.5 and 68.1 ± 4.1, respectively. A significant correlation between ATV/kg body weight and body weight was found for full-term (p < 0.0001) but not for preterm infants. TEE for preterm infants was 315 ± 20 kJ/kg body weight/24 h, which was significantly higher (p < 0.05) than TEE for full-term infants (254 ± 45 kJ/kg body weight/24 h). At the time of investigation preterm infants weighed significantly (p < 0.05) less (540 g) than full-term infants. After the time of investigation, weight gains of preterm and full-term infants were 38 ± 12 and 24 ± 14 g/24 h, respectively.

Conclusion: When compared to full-term newborns, predominantly breastfed healthy preterm infants at term postconceptional age were significantly smaller, had a similar average proportion of body fat and showed catch-up growth. Their higher TEE/kg body weight can be explained by a higher growth rate and possibly also by higher physical activity.

National Category
Medical and Health Sciences
Identifiers
urn:nbn:se:liu:diva-25018 (URN)10.1080/08035250310005396 (DOI)9439 (Local ID)9439 (Archive number)9439 (OAI)
Available from: 2009-10-07 Created: 2009-10-07 Last updated: 2012-10-10Bibliographically approved
4. Assessment of total body fat using the skinfold technique and body water dilution in fullterm and preterm infants under four months of age
Open this publication in new window or tab >>Assessment of total body fat using the skinfold technique and body water dilution in fullterm and preterm infants under four months of age
(English)Manuscript (preprint) (Other academic)
Abstract [en]

Aim: To evaluate a method based on measurements of skinfold thickness (SFT) in infants under four months of age.

Methods: Adipose tissue volume was assessed by means of magnetic resonance imaging and total body fat (TBF) by means of a method based on skinfold measurements previously developed for children under two years of age (TBF-SFT). Estimates of TBF obtained by means of body water dilution (TBF-BWD) represented reference values. The subjects were 45 fullterm infants, 4-131 days old, and eight premature infants born in gestational weeks 30-33 and studied at a postnatal age of 63 ± 10 days.

Results: In fullterm infants TBF-SFT and TBF-BWD were 23.3 ± 3.4 and 21.8 ± 7.0 %, respectively, and the difference between the two methods was non-significant. However TBF-SFT minus TBF-BWD (%, y) was significantly con-elated (p<0.0001) with the average TBF-SFT and TBF-BWD (%, x), showing that the skinfold method overstimated TBF in lean infants while it underestimated TBF in infants with a high body fat content. In fullterm infants adipose tissue (AT) contained 0.68 ± 0.14 g fat/ml. Significant correlations were found between the AT fat content (g/ml, y) and TBF-BWD (%, x) (p<0.0001 ), as well as between the AT fat content (g/ml, x) and TBF-SFT minus TBF-BWD (%, y) (p<0.0001). In premature infants TBF-SFT (%), TBF-BWD (%) and the AT fat content were similar to the corresponding figures for nine fullterm newborns.

Conclusion: In fullterm infants the skinfold method produced biased estimates of TBF, which to a large extent can be explained by a variation in the AT fat content. However, the method has the potential to provide meaningful results in groups of infants with similar AT fat content.

National Category
Medical and Health Sciences
Identifiers
urn:nbn:se:liu:diva-84498 (URN)
Available from: 2012-10-10 Created: 2012-10-10 Last updated: 2012-10-10Bibliographically approved

Open Access in DiVA

No full text

Authority records BETA

Olhager, Elisabeth

Search in DiVA

By author/editor
Olhager, Elisabeth
By organisation
PediatricsFaculty of Health Sciences
Medical and Health Sciences

Search outside of DiVA

GoogleGoogle Scholar

isbn
urn-nbn

Altmetric score

isbn
urn-nbn
Total: 149 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • oxford
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf