Prevalence and association of single nucleotide polymorphisms with sarcopenia in older women depends on definition

© 2020, The Author(s). The prevalence of sarcopenia depends on the definition used. There are, however, consistent sarcopenic characteristics, including a low muscle mass and muscle strength. Few studies have investigated the relationship between sarcopenia and genotype. A cross-sectional study was conducted with 307 community-dwelling ≥60-year-old women in South Cheshire, UK. Handgrip strength was assessed with a handgrip dynamometer and skeletal muscle mass was estimated using bioelectrical impedance. DNA was extracted from saliva (∼38%) or blood (∼62%) and 24 single-nucleotide polymorphisms (SNPs) were genotyped. Three established sarcopenia definitions - %Skeletal Muscle Mass (%SMM), Skeletal Muscle Mass Index (SMI) and European Working Group on Sarcopenia in Older People (EWGSOP) - were used to assess sarcopenia prevalence. Binary logistic regression with age as covariate was used to identify SNPs associated with sarcopenia. The prevalence of sarcopenia was: %SMM 14.7%, SMI 60.6% and EWGSOP 1.3%. Four SNPs were associated with the %SMM and SMI definitions of sarcopenia; FTO rs9939609, ESR1 rs4870044, NOS3 rs1799983 and TRHR rs7832552. The first three were associated with the %SMM definition, and TRHR rs7832552 with the SMI definition, but none were common to both sarcopenia definitions. The gene variants associated with sarcopenia may help proper counselling and interventions to prevent individuals from developing sarcopenia

Körperproportionen der Leistungsstärkstenjuniorenruderer im bezug auf Wettkampfniveau,den Stil des Ruderns und die Bootsgattung

The performance of elite rowers is, beside others, determined by their physical characteristics. Anthropometric data for adult rowers emphasise the importance of body mass and body size for rowing performance. Little is known concerning the importance of proportional length development. At the 1997 World Junior Rowing Championships anthropometric measurements (body mass and 6 length dimensions) were performed on 383 elite male junior rowers. Based on these measurements several proportional length dimensions were calculated. Data on boat type were obtained by questionnaire and data on competition level were based on the results obtained during the championship. The results indicate that these rowers were heavier (Mean = 82.2±7.4 kg) and taller (Mean = 187.4±5.8 cm) and had a larger sitting height (Mean=96.8±3.2 cm) and longer legs (Mean= 90.7±3.8 cm) than a reference population. Finalists had significantly larger length dimensions than non-finalists and sweep rowers had in general larger length dimensions than scullers. No differences existed when the length dimensions were expressed proportional to the stature of the rowers. It can be concluded that elite junior rowers have larger length dimensions compared to less successful rowers, but these top athletes do not differentiate from the sub-elite athletes regarding proportional length development. Differences could be observed between sweep rowers and scullers with larger length dimensions in favour of sweep rowers.Uvod Natjecateljska uspješnost vrhunskih veslača određena je, između ostaloga, i njihovim tjelesnim karakteristikama. S biološkog stajališta možemo kod sportaša olimpijske i svjetske razine kvalitete očekivati optimalnu ekspresiju utjecaja nasljeđa, sportske pripreme, prehrane i socio-kulturnih faktora. Ispitivanje obilježja tih sportaša može pomoći kineziolozima, znanstvenicima i trenerima, u razumijevanju vrhunskog sportskog uspjeha time što im pruža informacije korisne za oblikovanje strategija za objašnjenje i predviđanje sportskih rezultata. U prošlosti su se antropometrijske studije bavile uglavnom veslačima seniorima, a manje juniorima. Te antropometrijske studije naglašavaju važnost tjelesne mase i veličine tijela za uspješnost u veslanju. Smatra se da osobitu prednost veslačima donose duži udovi zbog toga što su to duže poluge i što omogućuju veću radnu snagu. Duge noge pojačavaju potisnu fazu (provlak) veslačkog zaveslaja. Štoviše, veći veslači imaju veći presjek mišića i veći apsolutni energetski kapacitet. Proučavanje longitudinalnih dimenzija do sada je bilo uglavnom ograničeno na varijablu “visina tijela ili stas”. Samo je nekoliko studija o proporcijama longitudinalnih dimenzija vrhunskih veslača, pa se malo zna o važnosti longitudinalnih proporcija tijela veslača. Cilj je ove studije bio trostruk: (1) opisati razvojne proporcijske longitudinalne dimenzije juniora veslača u usporedbi s flamanskim mladićima, (2) usporediti tjelesne proporcije veslača prema različitim kvalitetnim natjecateljskim razinama, načinu veslanja i kategorijama čamca i (3) ustanoviti model antropometrijskog profila za veslače juniore. Metode Uzorak ispitanika činila su 383 veslača juniora, u dobi od 17,8 ± 0,7 godina, raspon godina od 15,1 do 18,6. Ispitanici su nastupili na FISA svjetskom ju-niorskom veslačkom prvenstvu 1997 godine. Istraživanjem je obuhvaćeno 90% sudionika (bez kormilara), od toga 83% pobjednika i osvajača meda-lja te 89% finalista. Svi su trenirali 7-10 puta tjedno (10-15 sati). Potpuni opis uzorka i mjerenja može se naći u članku Bourgois i suradnici (1998). Za ovaj članak upotrijebljene su sljedeće tjelesne dimenzije: tjelesna visina, sjedeća visina, duljina nadlaktice, duljina podlaktice, duljina šake i duljina potkoljenice. Mjerenja su provedena u standardnim uvjetima prema postupcima koje su opisali Claessens i suradnici (1998). Na temelju tih mjera izračunate su proporcijske longitudinalne dimenzije. Pregled varijabli prikazan je u tablici 1. Podaci o vrsti čamca prikupljeni su upitnikom, a podaci o kvalitetnoj razini temeljili su se na rezultatima postignutima na prvenstvu. Međunarodna juniorska veslačka natjecanja standardizirana su na stazi od 2 000 m i podijeljena su u discipline veslanja jednim veslom (rimen) i veslanja na pariće (skul). Te se veslačke tehnike međusobno dosta razlikuju – veslač u čamcu rimen, dakle, vesla samo jednim veslom, dok skuleri koriste dva kraća vesla koja povlače istodobno. Izračunati su parametri deskriptivne statistike (aritmetička sredina, standardna devijacija i raspon) za sve varijable i za ukupni uzorak veslača. Za usporedbu proporcijskih odnosa između rimen veslača i skul veslača te finalista i onih koji se nisu plasirali u finale upotrijebljen je Studentov t-test za nezavisne uzorke. Analiza varijance (ANOVA) i post-hoc Tukeyjev test primijenjeni su da bi se otkrile razlike u proporcionalnosti među veslačima u raznim vrstama čamaca. Za statističke analize korišten je računalni program Statistical Analysis System. Svi su testovi bili dvostruki, a značajnom se smatrala razlika na razini od p<0.05. Rezultati Deskriptivna statistika prikazana je u tablici 3. U tablici su uspoređene proporcije veslača u rimenu i skulu. Rimen veslači bili su značajno viši i teži od skulera. Kada su se longitudinalne dimenzije dovele u proporcijski odnos prema tjelesnoj visini, nisu primijećene značajne razlike između te dvije vrste veslača. Slični su se rezultati dobili i u usporedbi finalista i ne-finalista (tablica 5). Prema rezultatima analize varijance (tablica 6) razlike između dva stila veslanja (rimen nasuprot skul) nađene su između dvojca sa (2+) i četverca sa (4+), s jedne strane, te samca (1x), četverca na pariće (4x) i dvojca bez (2-), s druge strane. Sportaši koji veslaju u dvojcu sa (2+) i četvercu sa (4+) bili su, u prosjeku, teži i viši od veslača u samcu (1x), četvercu na pariće (4x) i dvojcu bez (2-). Nisu dobivene razlike u proporcijskim odnosima longitudinalnih dimenzija prema vrsti čamaca. U tablici 7 predstavljen je model profila proporcijskih odnosa longitudinalnih dimenzija za veslače juniore koji su nastupili na FISA svjetskom juniorskom veslačkom prvenstvu. Rasprava i zaključak Rezultati pokazuju da su promatrani veslači teži i viši te da imaju veću sjedeću visinu i duže noge od opće populacije. Finalisti su imali značajno veće longitudinalne dimenzije od ne-finalista, a rimen veslači su općenito imali veće longitudinalne dimenzije od skulera. Nisu, međutim, dobivene razlike kada su longitudinalne dimenzije postavljene u proporcijski odnos prema tjelesnoj visini. Veslanje je sport izdržljivosti i longitudinalne dimenzije su nedvojbeno povezane s uspješnošću. Duge noge pojačavaju potisak u fazi provlaka tijekom veslačkog zaveslaja, što znači da su veslači s dugim nogama u biomehaničkoj prednosti. Usporedba tjelesnih proporcija izmjerenih veslača juniora s vrijednostima o kojima su izvijestili drugi autori (Carter i dr., 1982; Rodriguez, 1986) otkriva da veslači juniori imaju manju sjedeću visinu u odnosu na ukupnu tjelesnu visinu ili stas (Valoisov indeks) (51,6%) i veću duljinu nogu u odnosu na stas (48,4%) od normativne usporedne skupine (Ostyn i dr., 1980) (52,1% i 47,9%) i od teških olimpijskih veslača (Carter i dr, 1982) (52,1% i 47,.9%). Nisu dobivene razlike između veslača juniora i vrhunskih lakih veslača (51,5% i 48,5%). Može se zaključiti da su kvalitetniji veslači uglavnom viši i, povezano s tom razlikom, imaju veće longitudinalne dimenzije od manje uspješnih veslača, ali se oni ne razlikuju međusobno kada se te vrijednosti izraze proporcionalno u odnosu na njihovu tjelesnu visinu. Uočene su razlike između rimen veslača i skul veslača – rimen veslači su višega stasa i imaju veće apsolutne vrijednosti longitudinalnih dimenzija. Uz to što je izrađen profil veslača juniora, rezultati ove studije mogu pomoći trenerima i kineziolozima da steknu bolji uvid u to koje su morfološke karakteristike povezane s uspješnošću u veslanju. Rezultati se također mogu primijeniti za određenje antropometrijskog profila veslača i kao instrument za selekciju dječaka talentiranih za veslanje.Die Leistung der leistungsstärksten Ruderer ist unter anderem von ihren körperlichen Eigenschaften bestimmt. Körperbaudaten für erwachsene Ruderer stellen den Nachdruck auf die Wichtigkeit des Körpergewichts und der Körperhöhe für das Rudern. Es bleibt noch unklar, wie wichtig die proportionale Längenzunahme ist. Während der Junioren Weltmeisterschaften im 1997 wurden die Körperbau-Messungen (Körpergewicht und 6 Extremitätenlängen) auf 383 leistungsstärksten Junioren-Ruderer vorgenommen. Auf Grund dieser Messungen einige proportionale Extremitätenlängen wurden berechnet. Die Angaben über die Bootsgat-tung wurden einem Fragebogen entnommen, während die Angaben über dem Wettkampf-Niveau auf den während der Meisterschaft gewonnenen Ergebnissen basierten. Den Ergebnissen nach wogen diese Ruderer mehr (Mittelwert = 82,2±7,4 kg), sie waren größer (Mittelwert = 187,4±5,8 cm) und hatten eine größere Sitzhöhe (Mittelwert = 96,8±3,2 cm) und längere Beine (Mittelwert = 90,7±3,8 cm) als die Referenz-Grundgesamtheit. Die Finalisten hatten bedeutend größere Extremitätenlängenwerte als die Nicht-Finalisten, während die Riemenruderer im allgemeinen größere Extremitätenlängenwerte hatten als die Skuller. Keine Unterschiede waren zu merken, wenn die Extremitätenlängenwerte proportional der Körperhöhe der Ruderer dargestellt wurden. Daraus lässt sich schließen, dass die leistungsstärksten Junioren größere Extremitätenlängenwerte haben im Vergleich zu den weniger erfolgreichen Ruderern, aber diese Spitzensportler unterscheiden sich keineswegs von weniger erfolgreichen Sportlern im Bezug auf die proportionale Längenzunahme. Die Unterschiede sind bei den Riemenruderern und den Skullern zu merken, wobei die Skuller größere Extremitätenlängenwerte aufzeigen

Genetic regulation of body size and morphology in children: a twin study of 22 anthropometric traits

Background Anthropometric measures show high heritability, and genetic correlations have been found between obesity-related traits. However, we lack a comprehensive analysis of the genetic background of human body morphology using detailed anthropometric measures. Methods Height, weight, 7 skinfold thicknesses, 7 body circumferences and 4 body diameters (skeletal breaths) were measured in 214 pairs of twin children aged 3–18 years (87 monozygotic pairs) in the Autonomous Region of Madeira, Portugal. Factor analysis (Varimax rotation) was used to analyze the underlying structure of body physique. Genetic twin modeling was used to estimate genetic and environmental contributions to the variation and co-variation of the anthropometric traits. Results Together, two factors explained 80% of the variation of all 22 anthropometric traits in boys and 73% in girls. Obesity measures (body mass index, skinfold thickness measures, as well as waist and hip circumferences) and limb circumferences loaded most strongly on the first factor, whereas height and body diameters loaded especially on the second factor. These factors as well as all anthropometric measures showed high heritability (80% or more for most of the traits), whereas the rest of the variation was explained by environmental factors not shared by co-twins. Obesity measures showed high genetic correlations (0.75–0.98). Height showed the highest genetic correlations with body diameter measures (0.58–0.76). Correlations between environmental factors not shared by co-twins were weaker than the genetic correlations but still substantial. The correlation patterns were roughly similar in boys and girls. Conclusions Our results show high genetic correlations underlying the human body physique, suggesting that there are sets of genes widely affecting anthropometric traits. Better knowledge of these genetic variants can help to understand the development of obesity and other features of the human physique.The project “Genetic and environmental influences on physical activity, fitness and health: the Madeira family study” was supported by FCT - Fundação para a Ciência e a Tecnologia (The Portuguese National Funding Agency for Science, Research and Technology), reference POCI/DES/56834/2004. Open Access funding provided by University of Helsinki including Helsinki University Central Hospital

Genetic predisposition score predicts the increases of knee strength and muscle mass after one-year exercise in healthy elderly

This study aims to identify a genetic predisposition score from a set of candidate gene variants that predicts the response to a one-year exercise intervention. 200 participants (aged 60–83 years) were randomly assigned to a fitness (FIT), whole-body vibration (WBV) and control group. Participants in the exercise (FIT and WBV) groups performed a one-year intervention program. Whole-body skeletal muscle mass (SMM) and isometric knee extension strength (PTIM60) were measured before and after the intervention. A set of 170 muscle-related single nucleotide polymorphisms (SNPs) were genotyped. Stepwise regression analysis was applied to select significantly contributing SNPs for baseline and relative change parameters. A data-driven genetic predisposition score (GPS) was calculated by adding up predisposing alleles for each of the phenotypes. GPS was calculated based on 4 to 8 SNPs which were significantly related to the corresponding phenotypes. These SNPs belong to genes that are involved in myoblast differentiation, muscle and bone growth, myofiber contraction, cytokines and DNA methylation. GPS was related to baseline PTIM60and relative changes of SMM and PTIM60in the exercise groups, explaining the variance of the corresponding parameter by 3.2%, 14% and 27%, respectively. Adding one increasing allele in the GPS increased baseline PTIM60by 4.73 Nm, and exercise-induced relative changes of SMM and PTIM60by 1.78% and 3.86% respectively. The identified genetic predisposition scores were positively related to baseline knee extension strength and muscle adaptations to exercise in healthy elderly. These findings provide supportive genetic explanations for high and low responders in exercise-induced muscle adaptations

Gross motor coordination and weight status of Portuguese children aged 6-14 years

Objectives: To construct age- and gender-specific percentiles for gross motor coordination (MC) tests and to explore differences in gross MC in normal-weight, overweight and obese children. Methods: Data are from the "Healthy Growth of Madeira Study", a cross-sectional study carried out in children, aged 6–14 years. All 1,276 participants, 619 boys and 657 girls, were assessed for gross MC (Korperkoordinations Test fur Kinder, KTK), anthropometry (height and body mass), physical activity (Baecke questionnaire) and socioeconomic status (SES). Centile curves for gross MC were obtained for boys and girls separately using generalized additive models for location, scale and shape. Results: A significant main effect for age was found in walking backwards and moving sideways. Boys performed significantly better than girls on moving sideways. At the upper limit of the distributions, interindividual variability was higher in hopping on one leg (girls) and jumping and moving sideways (boys and girls). One-way ANCOVA, controlling for age, physical activity and SES, indicated that normal-weight children scored significantly better than their obese peers in all gross MC tests. Overweight boys and girls also scored significantly better than their obese colleagues in some MC tests. Conclusions: These centile curves can be used as reference data in Portuguese children and youth, aged 6–14 years. Being overweight or obese was a major limitation in MC tests and, therefore, of the children’s health- and performance related physical fitness

Sarcopenia, obesity, and sarcopenic obesity: Relationship with skeletal muscle phenotypes and single nucleotide polymorphisms

Obesity may aggravate the effects of sarcopenia on skeletal muscle structure and function in the elderly, but no study has attempted to identify the gene variants associated with sarcopenia in obese women. Therefore, the aims of the present study were to: (1) describe neuromuscular function in sarcopenic and non-sarcopenic women with or without obesity; (2) identify gene variants associated with sarcopenia in older obese women. In 307 Caucasian women (71 ± 6 years, 66.3 ± 11.3 kg), skeletal muscle mass was estimated using bioelectric impedance, and function was tested with a 30 s one-leg standing-balance test. Biceps brachii thickness and vastus lateralis cross-sectional area (VLACSA) were measured with B-mode ultrasonography. Handgrip strength, maximum voluntary contraction elbow flexion (MVCEF), and knee extension torque (MVCKE) were measured by dynamometry, and MVCKE/VLACSA was calculated. Genotyping was performed for 24 single-nucleotide polymorphisms (SNPs), selected based on their previous associations with muscle-related phenotypes. Based on sarcopenia and obesity thresholds, groups were classified as sarcopenic obese, non-sarcopenic obese, sarcopenic non-obese, or non-sarcopenic non-obese. A two-way analysis of covariance was used to assess the main effects of sarcopenia and obesity on muscle-related phenotypes and binary logistic regression was performed for each SNP to investigate associations with sarcopenia in obesity. There were no significant obesity * sarcopenic status interactions for any of the investigated muscle-related phenotypic parameters. Neither sarcopenia nor obesity had a significant effect on biceps brachii thickness, but sarcopenia was associated with lower VLACSA (p = 0.003). Obesity was associated with lower MVCEF (p = 0.032), MVCKE (p = 0.047), and MVCKE/VLACSA (p = 0.012) with no significant effect of sarcopenia. Adjusted for age and height, three SNPs (ACTN3 rs1815739, MTHFR rs1801131, and MTHFR rs1537516) were associated with sarcopenia in obese participants. Sarcopenia was associated with a smaller muscle size, while obesity resulted in a lower muscle quality irrespective of sarcopenia. Three gene variants (ACTN3 rs1815739, MTHFR rs1801131, and MTHFR rs1537516) suspected to affect muscle function, homocysteine metabolism, or DNA methylation, respectively, were associated with sarcopenia in obese elderly women. Understanding the skeletal muscle features affected by sarcopenia and obesity, and identification of genes related to sarcopenia in obese women, may facilitate early detection of individuals at particular risk of sarcopenic obesity

Static one-leg standing balance test as a screening tool for low muscle mass in healthy elderly women

Background: Identification of simple screening tools for detecting lower skeletal muscle mass may be beneficial for planning effective interventions in the elderly. Aims: We aimed to (1) establish a threshold for one-leg standing balance test (OLST) time for low muscle mass, and (2) test the ability of that threshold to assess muscular impairments in a poor balance group. Methods: Eyes-open OLST (maximum duration 30 s) was performed with right and left legs in 291 women (age 71 ± 6 years). OLST time was calculated as the sum of the OLST time of right and left legs. Fat-free mass (FFM), skeletal muscle mass (SMM), fat mass, biceps brachii and vastus lateralis sizes; handgrip strength (HGS), elbow flexion maximum torque (MVC ) and knee extension maximum torque (MVC ) were measured. Muscle quality was calculated as MVC /FFM and physical activity was assessed by questionnaire. Low muscle mass was defined as SMM of 22.1%, a previously established threshold for pre-sarcopenia. Results: The OLST threshold time to detect low muscle mass was 55 s (sensitivity: 0.63; specificity: 0.60). The poor balance group (OLST < 55 s) had higher fat mass (3.0%, p < 0.001), larger VL thickness (5.1%, p = 0.016), and lower HGS (− 10.2%, p < 0.001), MVC (− 8.2%, p = 0.003), MVC (− 9.5%, p = 0.012), MVC /FFM (− 11.0%, p = 0.004) and physical activity (− 8.0%, p = 0.024) compared to the normal balance group. While after adjusting age, the differences exist for HGS, fat mass and VL thickness only. Discussion: An OLST threshold of 55 s calculated as the summed score from both legs discriminated pre-sarcopenic characteristics among active, community-dwelling older women with limited potential (sensitivity 0.63, specificity 0.60). Conclusion: OLST, which can be performed easily in community settings without the need for more complex muscle mass measurement, may help identify women at risk of developing sarcopenia. EF KE KE relative EF KE K

Dietary protein requirement threshold and micronutrients profile in healthy older women based on relative skeletal muscle mass

Although multiple nutrients have shown protective effects with regard to preserving muscle function, the recommended amount of dietary protein and other nutrients profile on older adults for maintenance of high muscle mass is still debatable. The aims of this paper were to: (1) identify dietary differences between older women with low and high relative skeletal muscle mass, and (2) identify the minimal dietary protein intake associated with high relative skeletal muscle mass and test the threshold ability to determine an association with skeletal muscle phenotypes. Older women (n = 281; 70 ± 7 years, 65 ± 14 kg), with both low and high relative skeletal muscle mass groups, completed a food questionnaire. Skeletal muscle mass, fat-free mass (FFM), biceps brachii thickness, vastus lateralis anatomical cross-sectional area (VLACSA ), handgrip strength (HGS), maximum elbow flexion torque (MVCEF ), maximum knee extension torque (MVCKE ), muscle quality (HGS/Body mass), and fat mass were measured. Older women with low relative skeletal muscle mass had a lower daily intake of protein, iodine, polyunsaturated fatty acid (PUFA), Vit E, manganese, milk, fish, nuts and seeds (p < 0.05) compared to women with high relative skeletal muscle mass. The minimum required dietary protein intake for high relative skeletal muscle mass was 1.17 g/kg body mass/day (g/kg/d) (sensitivity: 0.68; specificity: 0.62). Women consuming ≥1.17 g/kg/d had a lower BMI (B = −3.9, p < 0.001) and fat mass (B = −7.8, p < 0.001), and a higher muscle quality (B = 0.06, p < 0.001). The data indicate that to maintain muscle mass and function, older women should consume ≥1.17 g/kg/d dietary protein, through a varied diet including milk, fish and nuts that also contain polyunsaturated fatty acid (PUFA) and micronutrients such as iodine, Vit E and manganese

Paediatric lymphoedema : An audit of patients seen by the paediatric and primary lymphoedema group of vascular European Reference Network (VASCERN)

Little is known about the overall prevalence of lymphoedema in children and the types of paediatric lymphoedema seen by specialist centres. Therefore, this study was aimed to provide a profile of children with primary or secondary lymphoedema seen by the expert centres of the paediatric and primary lymphoedema working group (PPL-WG) of VASCERN and to compare the profile between the different countries.A retrospective review of all children (aged up to 18 years) seen for the first time by the expert centres over one year (2019) was carried out. Lymphoedema-, patient- and genetics-related data was collected and described for the whole group and compared between the different European countries/UK.In 2019, a total of 181 new children were seen by eight expert centres. For primary lymphoedema, the phenotype was based on the St George's classification of lymphatic anomalies. The percentages diagnosed according to each category were: 7.2% for syndromic lymphoedema, 2.8% for systemic/visceral involvement, 30.4% for congenital, 35.9% for late-onset lymphoedema and 19.3% for vascular/lymphatic malformations. 4.4% had secondary lymphoedema. Nearly 10% of all children had had at least one episode of cellulitis. The median delay from onset of symptoms to being seen by an expert centre was 2.4 years. In 44.4% of the children with primary lymphoedema a genetic test was performed, of which 35.8% resulted in a molecular diagnosis. Across the different centres, there was a wide variety in distribution of the different categories of paediatric lymphoedema diagnosed and the frequency of genetic testing.In conclusion, this paper has demonstrated that there is a large delay between the onset of paediatric lymphoedema and the first visit in the expert centres and that an episode of cellulitis is a relatively common complication. Diagnostic variation across the centres may reflect different referral criteria. Access to genetic testing was limited in some centres. It is recommended that these issues are addressed in the future work of the PPL-WG to improve the referral to the expert centres and the consistency in service provision for paediatric lymphoedema in Europe.Peer reviewe

Genetic, Maternal and Placental Factors in the Association between Birth Weight and Physical Fitness: A Longitudinal Twin Study

Background Adult cardiorespiratory fitness and muscle strength are related to all-cause and cardiovascular mortality. Both are possibly related to birth weight, but it is unclear what the importance is of genetic, maternal and placental factors in these associations. Design Peak oxygen uptake and measures of strength, flexibility and balance were obtained yearly during adolescence (10–18 years) in 114 twin pairs in the Leuven Longitudinal Twin Study. Their birth weights had been collected prospectively within the East Flanders Prospective Twin Survey. Results We identified linear associations between birth weight and adolescent vertical jump (b = 1.96 cm per kg birth weight, P = 0.02), arm pull (b = 1.85 kg per kg birth weight P = 0.03) and flamingo balance (b = −1.82 attempts to stand one minute per kg birth weight, P = 0.03). Maximum oxygen uptake appeared to have a U-shaped association with birth weight (the smallest and largest children had the lowest uptake, P = 0.01), but this association was no longer significant after adjustment for parental BMI. Using the individual twin’s deviation from his own twin pair’s average birth weight, we found positive associations between birth weight and adolescent vertical jump (b = 3.49, P = 0.0007) and arm pull (b = 3.44, P = 0.02). Δ scores were calculated within the twin pairs as first born twin minus second born twin. Δ birth weight was associated with Δ vertical jump within MZ twin pairs only (b = 2.63, P = 0.009), which indicates importance of placental factors. Conclusions We found evidence for an association between adolescent physical performance (strength, balance and possibly peak oxygen uptake) and birth weight. The associations with vertical jump and arm pull were likely based on individual, more specifically placental (in the case of vertical jump) factors. Our results should be viewed as hypothesis-generating and need confirmation, but potentially support preventive strategies to optimize birth weight, for example via placental function, to target later fitness and health