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- Holmgren, Anton, et al.
(författare)
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Insight into human pubertal growth by applying the QEPS growth model.
- 2017
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Ingår i: BMC pediatrics. - : Springer Science and Business Media LLC. - 1471-2431. ; 17:107
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Tidskriftsartikel (refereegranskat)abstract
- Computerized mathematical models describing absolute and relative individual growth during puberty in both cm and standard deviation (SD)-scores are lacking. The present study aimed to fill this gap, by applying the QEPS-model that delineates mathematically the specific pubertal functions of the total growth curve.Study population used was the individual growth curves of the longitudinally followed cohort GrowUp1974 Gothenburg (n=2280). The QEPS-model describes total height as (T)otal-function: a combination of four shape-invariant growth functions, modified by time-scale and height-scale parameters: a (Q)uadratic-function for the continuous growth from fetal life to adulthood; a negative (E)xponential-function adds the rapid, declining fetal/infancy growth; a (P)ubertal-function the specific pubertal growth spurt; a (S)top-function the declining growth until adult height. A constructed variable, MathSelect, was developed for assessing data-quality. CIs and SD-scores for growth estimates were calculated for each individual. QEPS-model estimates used for pubertal growth; from the T-function: onset of puberty as minimal height velocity (AgeT ONSET ); mid-puberty as peak height velocity (AgeT PHV ); end of puberty as height velocity decreased to 1cm/year (AgeT END ); duration of different intervals and gain (AgeT ONSET-END and Tpubgain); from the P-function: onset of puberty, estimated as growth at 1% or 5% (AgeP1 , AgeP5); mid-puberty as 50% (AgeP50) and PHV (AgeP PHV ); end of pubertal growth at 95 or 99% (AgeP95, AgeP99); duration of different intervals and pubertal gain (Ppubgain; P max ); from the QES-function: gain (QESpubgain) . RESULTS: Application of these mathematical estimates for onset, middle and end of puberty of P-function, QES-function, and T-function during puberty showed: the later the onset of puberty, the greater the adult height; pubertal gain due to the P-function growth was independent of age at onset of puberty; boys had higher total gain during puberty due to P-function growth than to QES-function growth; for girls it was reversed.QEPS is the first growth model to provide individualized estimates of both the specific pubertal growth function and the total growth during puberty, with accompanying SD-scores and Cis for each individual. These QEPS-derived estimates enable more in-depth analysis of different aspects of pubertal growth than previously possible.
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| 2. |
- Holmgren, Anton, et al.
(författare)
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Pubertal height gain is inversely related to peak BMI in childhood.
- 2017
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Ingår i: Pediatric research. - : Springer Science and Business Media LLC. - 1530-0447 .- 0031-3998. ; 81:3, s. 448-454
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Tidskriftsartikel (refereegranskat)abstract
- BackgroundChildhood BMI may influence subsequent growth in height as well as the timing of puberty. The aim of the present study was to investigate associations between BMI in childhood and subsequent height gain/pubertal growth.MethodsLongitudinal growth data were used (GrowUp1990 Gothenburg cohort, n=1901). The QEPS growth-model was used to characterize height gain in relation to the highest BMISDS value between 3.5 and 8 years of age. Children were defined as overweight/obese (OwOb) or normal weight/underweight (NwUw), using the 2012 International Obesity Task Force criteria.ResultsA negative association between childhood BMISDS and pubertal height gain was observed. Already at birth, OwOb children were heavier than NwUw children, and had a greater height velocity during childhood. Onset of puberty was 3.5/3.0 months earlier in OwOb girls/boys, and they had 2.3/3.1cm less pubertal height gain from the QEPS-models specific P-function than NwUw children. Adult height was not related to childhood BMI.ConclusionWe found that pubertal height gain was inversely related to peak BMI in childhood. Higher childhood BMISDS was associated with more growth before onset of puberty, earlier puberty and less pubertal height gain, resulting in similar adult heights for OwOb and NwUw children.
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