Cognition, structural brain changes and complicated grief. A population-based study

BACKGROUND

Several psychosocial risk factors for complicated grief have been described. However, the association of complicated grief with cognitive and biological risk factors is unclear. The present study examined whether complicated grief and normal grief are related to cognitive performance or structural brain volumes in a large population-based study.

METHOD

The present research comprised cross-sectional analyses embedded in the Rotterdam Study. The study included 5501 non-demented persons. Participants were classified as experiencing no grief (n = 4731), normal grief (n = 615) or complicated grief (n = 155) as assessed with the Inventory of Complicated Grief. All persons underwent cognitive testing (Mini-Mental State Examination, Letter-Digit Substitution Test, Stroop Test, Word Fluency Task, word learning test - immediate and delayed recall), and magnetic resonance imaging to measure general brain parameters (white matter, gray matter), and white matter lesions. Total brain volume was defined as the sum of gray matter plus normal white matter and white matter lesion volume. Persons with depressive disorders were excluded and analyses were adjusted for depressive symptoms.

RESULTS

Compared with no-grief participants, participants with complicated grief had lower scores for the Letter-Digit Substitution Test [Z-score -0.16 v. 0.04, 95% confidence interval (CI) -0.36 to -0.04, p = 0.01] and Word Fluency Task (Z-score -0.15 v. 0.03, 95% CI -0.35 to -0.02, p = 0.02) and smaller total volumes of brain matter (933.53 ml v. 952.42 ml, 95% CI -37.6 to -0.10, p = 0.04).

CONCLUSIONS

Participants with complicated grief performed poorly in cognitive tests and had a smaller total brain volume. Although the effect sizes were small, these findings suggest that there may be a neurological correlate of complicated grief, but not of normal grief, in the general population.

Infant dietary patterns and bone mass in childhood: the Generation R Study

Early life nutrition affects peak bone mass attainment. In this prospective cohort study, children with high adherence to a "dairy and whole grains" pattern in infancy had higher bone mineral density at the age of 6 years. Although the observed effects are small, our study provides insight into mechanisms linking early nutrition to bone acquisition in childhood.

INTRODUCTION

Nutrition in early life may affect peak bone mass attainment. Previous studies on childhood nutrition and skeletal health mainly focused on individual nutrients, which does not consider the cumulative effects of nutrients. We investigated the associations between dietary patterns in infancy and childhood bone health.

METHODS

This study included 2850 children participating in a population-based prospective cohort study. Dietary information was obtained from a food frequency questionnaire at the age of 13 months. Using principal component analysis, three major dietary patterns were extracted, explaining in total 30% of the variation in dietary intake. At the age of 6 years, a total body dual-energy X-ray absorptiometry (DXA) scan was performed, and bone mineral density (BMD), bone mineral content (BMC), area-adjusted BMC (aBMC), and bone area (BA) were analyzed.

RESULTS

Higher adherence score to a "dairy and whole grains" pattern was positively associated with BMD and aBMC, but not with BMC and BA. Accordingly, children in the highest quartile of the "dairy and whole grains" pattern had higher BMD (difference 3.98 mg/cm(2), 95% confidence interval (CI) 0.36 to 7.61) and aBMC (difference 4.96 g, 95% CI 1.27 to 8.64) than children in the lowest quartile. Stratification for vitamin D supplementation showed that the positive associations between the "dairy and whole grains" pattern and bone outcomes were only observed in children who did not receive vitamin D supplementation. A "potatoes, rice, and vegetables" and a "refined grains and confectionery" pattern were not consistently associated with bone outcomes.

CONCLUSIONS

An infant dietary pattern characterized by high intakes of dairy and cheese, whole grains, and eggs is positively associated with bone development in childhood. Further research is needed to investigate the consequences for bone health in later life.

Early pregnancy maternal and fetal angiogenic factors and fetal and childhood growth: the Generation R Study

STUDY QUESTION

What are the effects of maternal and fetal soluble fms-like tyrosine kinase 1 (sFlt-1) and placental growth factor (PlGF) concentrations on fetal and childhood growth patterns?

SUMMARY ANSWER

An angiogenic profile that is characterized by both low early pregnancy maternal sFlt-1 and PlGF concentrations and higher sFlt-1 concentrations, lower PlGF concentrations or a higher sFlt-1:PlGF ratio in umbilical cord blood is associated with a reduced fetal and childhood growth.

WHAT IS KNOWN ALREADY

An imbalance in maternal and fetal sFlt-1 and PlGF concentrations has been suggested to affect pregnancy outcomes. However, their effects on longitudinal fetal and childhood growth remain largely unknown.

STUDY DESIGN, SIZE, DURATION

This study was performed in 5980 mothers and 4108 of their children, participating in the Generation R Study; a population-based prospective cohort study from fetal life onwards in Rotterdam, the Netherlands (2001-2005).

PARTICIPANTS/MATERIALS, SETTING, METHODS

Blood samples were obtained from mothers in early and mid-pregnancy and from the umbilical vein at delivery. Fetal and childhood growth characteristics (weight and length) were measured repeatedly by ultrasound and physical examinations until the age of 6 years. We assessed the associations of maternal and fetal angiogenic factors with fetal and childhood growth using repeated measurement regression models. Logistic regression models were used to determine associations between angiogenic factors and small for gestational age at birth (SGA).

MAIN RESULTS AND THE ROLE OF CHANCE

Compared with early pregnancy maternal sFlt-1 concentrations in the lowest quintile, early pregnancy maternal sFlt-1 concentrations in the highest quintile were associated with a higher fetal weight growth resulting in a higher birthweight (difference in birthweight 0.33 standard deviation score (SDS); 95% Confidence Interval (CI) 0.25-0.41), a lower risk of SGA (Odds Ratio (OR) 0.36; 95% CI 0.27-0.48) and a subsequent higher weight growth until the age of 6 years. Early pregnancy maternal PlGF concentrations in the lowest quintile were associated with a reduced weight growth pattern resulting in a smaller birthweight (difference in birthweight -0.34 SDS; 95% CI -0.44, -0.25), an increased risk of SGA (OR 3.48; 95% CI 2.39-5.08) and a lower weight growth throughout childhood. An early pregnancy maternal sFlt-1:PlGF ratio in the highest quintile was associated with a higher fetal weight growth pattern from 30 weeks onwards, resulting in a higher weight at birth (difference in birthweight 0.09 SDS; P-value <0.05), which remained present until the age of 2 years. Newborns with higher umbilical cord sFlt-1 concentrations, lower PlGF concentrations or a higher sFlt-1:PlGF ratio showed a lower fetal and childhood weight growth from 30 weeks gestation onwards until the age of 6 years (P-value <0.05). Similar patterns were observed in relation to fetal and childhood length growth.

LIMITATIONS, REASONS FOR CAUTION

The study is an observational study. Therefore, no causal relationships can be established.

WIDER IMPLICATIONS OF THE FINDINGS

Both a maternal and fetal angiogenic imbalance may affect fetal and childhood growth. Changes in angiogenic profiles may be involved in the pathways linking fetal growth restriction with the long-term risk of vascular disease in adulthood.

STUDY FUNDING/COMPETING INTERESTS

The first phase of the Generation R Study is made possible by financial support from The Erasmus Medical Centre, Rotterdam, the Erasmus University Rotterdam, and the Netherlands Organization for Health Research and Development (ZonMw 21000074). V.W.V.J. received additional grants from the Netherlands Organization for Health Research and Development (ZonMw VIDI). M.I.B.-B. is financially supported by the Bo Hjelt foundation (grant 2009). The authors have no competing interests.

Does fetal smoke exposure affect childhood bone mass? The Generation R Study

We assessed the intrauterine influence of maternal smoking on childhood bone mass by comparing parental prenatal and postnatal smoking habits. We observed higher bone mass in children exposed to maternal smoking, explained by higher body weight. Maternal smoking or related lifestyle factors may affect childhood weight gain rather than skeletal growth.

INTRODUCTION

Maternal smoking during pregnancy may adversely affect bone health in later life. By comparing the associations of maternal and paternal smoking and of prenatal and postnatal exposure with childhood bone measures, we aimed to explore whether the suggested association could be explained by fetal programming or reflects confounding by familial factors.

METHODS

In 5565 mothers, fathers and children participating in a population-based prospective cohort study, parental smoking habits during pregnancy and current household smoking habits were assessed by postal questionnaires. Total body bone mineral content (BMC), bone area (BA) and bone mineral density (BMD) were measured by dual-energy X-ray absorptiometry (DXA) at the median age of 6.0 years (IQR 0.37).

RESULTS

In confounder-adjusted models, maternal smoking during pregnancy was associated with a higher BMC of 11.6 g (95 % confidence interval (CI) 5.6, 17.5), a larger BA of 9.7 cm(2) (95 % CI 3.0, 16.4), a higher BMD of 6.7 g/cm(2) (95 % CI 2.4, 11.0) and a higher BMC of 5.4 g (95 % CI 1.3, 9.6) adjusted for BA of the child. Current weight turned out to mediate these associations. Among mothers who did not smoke, paternal smoking did not show evident associations with childhood bone measures. Also, household smoking practices during childhood were not associated with childhood bone measures.

CONCLUSIONS

Our results do not support the hypothesis of fetal smoke exposure affecting childhood bone mass via intrauterine mechanisms. Maternal smoking or related lifestyle factors may affect childhood weight gain rather than skeletal growth.

Vitamin D status and metabolic syndrome in the elderly: the Rotterdam Study

OBJECTIVE

The effects of vitamin D in the elderly are inconsistent. The aim of this study was to evaluate the association between vitamin D status and the metabolic syndrome (MetS) in the elderly, as well as between vitamin D status and the components of MetS (i.e. serum glucose, triglycerides (TG), HDL cholesterol (HDL-C), waist circumference (WC), and blood pressure (BP)).

METHODS

The study was embedded in the Rotterdam Study, a population-based cohort of middle-aged and elderly adults. We analyzed data from 3240 people (median age 71.2 years) who did not have type 2 diabetes mellitus at baseline.

RESULTS

We found higher 25-hydroxyvitamin D (25(OH)D) concentrations associated with lower prevalence of MetS (odds ratio (OR); 95% CI: 0.61; 0.49, 0.77 for adequate levels (≥75  nmol/l) vs deficiency (<50  nmol/l). In addition, in analysis of the individual components, the ORs for adequate vs deficient vitamin D levels were: 0.66 (95% CI 0.53, 0.83) for elevated WC, 0.67 (95% CI 0.52, 0.86) for reduced HDL-C, 0.69 (95% CI 0.54, 0.88) for elevated TG, and 0.80 (95% CI 0.65, 0.99) for elevated fasting glucose. Vitamin D was not associated with elevated blood pressure, and ORs for adequacy vs deficiency were 0.82 (95% CI 0.65, 1.03).

CONCLUSION

Higher 25(OH)D concentrations in the elderly are associated with lower prevalence of MetS and, in particular, with more beneficial HDL-C, TG, WC, and serum glucose. Since the prevalence of vitamin D deficiency is common worldwide and its risk increases with age, if causality is proven, benefits of improving vitamin D status among the elderly may be great.

Sugar-containing beverage intake in toddlers and body composition up to age 6 years: the Generation R study

BACKGROUND/OBJECTIVE

Intake of sugar-containing beverages (SCBs) has been associated with higher body mass index (BMI) in childhood. The potential effect of SCB intake during infancy is unclear. We examined the association of SCB intake at 13 months with BMI development until 6 years and body composition at age 6 years.

SUBJECTS/METHODS

This study included 2371 Dutch children from a population-based prospective cohort study. SCB intake at 13 months was assessed using a Food Frequency Questionnaire with validation against 24-h recalls and was standardized for total energy. BMI was calculated from repeated weight and height measurements, and age- and sex-specific s.d. scores were calculated. Adiposity was measured using Dual-energy X-ray absorptiometry.

RESULTS

In girls, higher SCB intake at 13 months was significantly associated with higher BMI at ages 2, 3, 4 and 6 years (at age 6 years BMI (s.d. score) increase 0.11 (95% confidence interval (CI) +0.00; 0.23), high versus low intake). We observed a tendency towards higher android/gynoid fat ratio in girls with high intake (s.d. increase 0.14 (95% CI -0.02; 0.29), versus low intake) but not with body fat percentage. In boys, there was no association with BMI or body composition, but boys with high SCB intake at 13 months were taller at age 6 years (s.d. increase 0.14 (95% CI +0.00; 0.27), versus low intake).

CONCLUSIONS

Higher SCB intake at 13 months was associated with higher BMI up to age 6 years in girls but not in boys. Our results imply that the unfavorable effects of SCB intake start early in life and that dietary advice regarding limiting SCB intake should already be given early in life.

Genetic contributions to variation in general cognitive function: a meta-analysis of genome-wide association studies in the CHARGE consortium (N=53949)

General cognitive function is substantially heritable across the human life course from adolescence to old age. We investigated the genetic contribution to variation in this important, health- and well-being-related trait in middle-aged and older adults. We conducted a meta-analysis of genome-wide association studies of 31 cohorts (N=53,949) in which the participants had undertaken multiple, diverse cognitive tests. A general cognitive function phenotype was tested for, and created in each cohort by principal component analysis. We report 13 genome-wide significant single-nucleotide polymorphism (SNP) associations in three genomic regions, 6q16.1, 14q12 and 19q13.32 (best SNP and closest gene, respectively: rs10457441, P=3.93 × 10(-9), MIR2113; rs17522122, P=2.55 × 10(-8), AKAP6; rs10119, P=5.67 × 10(-9), APOE/TOMM40). We report one gene-based significant association with the HMGN1 gene located on chromosome 21 (P=1 × 10(-6)). These genes have previously been associated with neuropsychiatric phenotypes. Meta-analysis results are consistent with a polygenic model of inheritance. To estimate SNP-based heritability, the genome-wide complex trait analysis procedure was applied to two large cohorts, the Atherosclerosis Risk in Communities Study (N=6617) and the Health and Retirement Study (N=5976). The proportion of phenotypic variation accounted for by all genotyped common SNPs was 29% (s.e.=5%) and 28% (s.e.=7%), respectively. Using polygenic prediction analysis, ~1.2% of the variance in general cognitive function was predicted in the Generation Scotland cohort (N=5487; P=1.5 × 10(-17)). In hypothesis-driven tests, there was significant association between general cognitive function and four genes previously associated with Alzheimer's disease: TOMM40, APOE, ABCG1 and MEF2C.

A genome-wide association meta-analysis of plasma Aβ peptides concentrations in the elderly

Amyloid beta (Aβ) peptides are the major components of senile plaques, one of the main pathological hallmarks of Alzheimer disease (AD). However, Aβ peptides' functions are not fully understood and seem to be highly pleiotropic. We hypothesized that plasma Aβ peptides concentrations could be a suitable endophenotype for a genome-wide association study (GWAS) designed to (i) identify novel genetic factors involved in amyloid precursor protein metabolism and (ii) highlight relevant Aβ-related physiological and pathophysiological processes. Hence, we performed a genome-wide association meta-analysis of four studies totaling 3 528 healthy individuals of European descent and for whom plasma Aβ1-40 and Aβ1-42 peptides levels had been quantified. Although we did not observe any genome-wide significant locus, we identified 18 suggestive loci (P<1 × 10(-)(5)). Enrichment-pathway analyses revealed canonical pathways mainly involved in neuronal functions, for example, axonal guidance signaling. We also assessed the biological impact of the gene most strongly associated with plasma Aβ1-42 levels (cortexin 3, CTXN3) on APP metabolism in vitro and found that the gene protein was able to modulate Aβ1-42 secretion. In conclusion, our study results suggest that plasma Aβ peptides levels are valid endophenotypes in GWASs and can be used to characterize the metabolism and functions of APP and its metabolites.

A genetic variant in SLC6A20 is associated with Type 2 diabetes in white-European and Chinese populations

AIMS

To investigate whether polymorphisms in SLC6A20 are associated with susceptibility to Type 2 diabetes.

METHODS

In the Rotterdam Study, a prospective, population-based cohort (n = 5974), 22 tagging polymorphisms with minor allele frequencies>0.05 across SLC6A20 were studied. Replication studies were performed in an independent Dutch case-control study (DiaGene-Rotterdam Study 2 n = 3133), and in a Chinese Han case-control population (n = 2279). A meta-analysis of the results was performed.

RESULTS

In the Rotterdam study, the minor alleles of rs13062383, rs10461016 and rs2286489 increased the risk of Type 2 diabetes (hazard ratio 1.37, 95% CI 1.15-1.63, hazard ratio 1.30 95% CI 1.09-1.54 and hazard ratio 1.20, 95% CI 1.07-1.35, respectively). In the DiaGene/Rotterdam Study 2, the A allele of rs13062383 increased the risk of Type 2 diabetes (odds ratio 1.45, 95% CI 1.19-1.76). In the Chinese Han study, the rs13062383 A allele also increased the risk of Type 2 diabetes (odds ratio 1.21, 95% CI 1.03-1.42). Meta-analysis showed a highly significant association of rs13062383 with Type 2 diabetes (odds ratio 1.35, 95% CI 1.21-1.47; P = 3.3 × 10⁻⁸).

CONCLUSIONS

In conclusion, rs13062383 in SLC6A20 increased the susceptibility to Type 2 diabetes in populations with different genetic backgrounds.

Cortical thickness and inattention/hyperactivity symptoms in young children: a population-based study

BACKGROUND

While many neuroimaging studies have investigated the neurobiological basis of attention deficit hyperactivity disorder (ADHD), few have studied the neurobiology of attention problems in the general population. The ability to pay attention falls along a continuum within the population, with children with ADHD at one extreme of the spectrum and, therefore, a dimensional perspective of evaluating attention problems has an added value to the existing literature. Our goal was to investigate the relationship between cortical thickness and inattention and hyperactivity symptoms in a large population of young children.

METHOD

This study is embedded within the Generation R Study and includes 6- to 8-year-old children (n = 444) with parent-reported attention and hyperactivity measures and high-resolution structural imaging data. We investigated the relationship between cortical thickness across the entire brain and the Child Behavior Checklist Attention Deficit Hyperactivity Problems score.

RESULTS

We found that greater attention problems and hyperactivity were associated with a thinner right and left postcentral gyrus. When correcting for potential confounding factors and multiple testing, these associations remained significant.

CONCLUSIONS

In a large, population-based sample we showed that young (6- to 8-year-old) children who show more attention problems and hyperactivity have a thinner cortex in the region of the right and left postcentral gyrus. The postcentral gyrus, being the primary somatosensory cortex, reaches its peak growth early in development. Therefore, the thinner cortex in this region may reflect either a deviation in cortical maturation or a failure to reach the same peak cortical thickness compared with children without attention or hyperactivity problems.

Maternal weight gain in different periods of pregnancy and childhood cardio-metabolic outcomes. The Generation R Study

BACKGROUND

Excessive gestational weight gain seems to be associated with offspring cardio-metabolic risk factors. Little is known about the critical periods of gestational weight gain. We examined the associations of maternal weight gain in different periods of pregnancy with childhood cardio-metabolic risk factors.

METHODS

In a population-based prospective cohort study from early pregnancy onwards among 5908 mothers and their children, we obtained maternal prepregnancy weight and weight in early, mid and late pregnancy. At the age of 6 years (median: 72.6 months; 95% range: 67.9, 95.8), we measured childhood body mass index (BMI), total body and abdominal fat distribution, blood pressure and blood levels of lipids, insulin and c-peptide.

RESULTS

Overall, the associations of maternal prepregnancy weight with childhood outcomes were stronger than the associations of maternal gestational weight gain. Independent from maternal prepregnancy weight and weight gain in other periods, higher weight gain in early pregnancy was associated with higher childhood BMI, total fat mass, android/gynoid fat mass ratio, abdominal subcutaneous fat mass and systolic blood pressure (P-values<0.05). Independent associations of maternal weight gain in early pregnancy with childhood abdominal preperitoneal fat mass, insulin and c-peptide were of borderline significance. Higher weight gain in mid pregnancy was independently associated with higher childhood BMI, total and abdominal subcutaneous fat mass and systolic blood pressure (P-values<0.05). The associations for childhood cardio-metabolic outcomes attenuated after adjustment for childhood BMI. Weight gain in late pregnancy was not associated with childhood outcomes. Higher weight gain in early, but not in mid or late pregnancy, was associated with increased risks of childhood overweight and clustering of cardio-metabolic risk factors (odds ratio (OR) 1.19 (95% confidence interval (CI): 1.10, 1.29) and OR 1.20 (95% CI: 1.07, 1.35) per standard deviation increase in early gestational weight gain, respectively).

CONCLUSIONS

Higher weight gain in early pregnancy is associated with an adverse cardio-metabolic profile in offspring. This association is largely mediated by childhood adiposity.

Sex-specific effects of naturally occurring variants in the dopamine receptor D2 locus on insulin secretion and type 2 diabetes susceptibility

AIMS

Modulation of dopamine receptor D2 (DRD2) activity affects insulin secretion in both rodents and isolated pancreatic β-cells. We hypothesized that single nucleotide polymorphisms in the DRD2/ANKK1 locus may affect susceptibility to type 2 diabetes in humans.

METHODS

Four potentially functional variants in the coding region of the DRD2/ANKK1 locus (rs1079597, rs6275, rs6277, rs1800497) were genotyped and analysed for type 2 diabetes susceptibility in up to 25 000 people (8148 with type 2 diabetes and 17687 control subjects) from two large independent Dutch cohorts and one Danish cohort. In addition, 340 Dutch subjects underwent a 2-h hyperglycaemic clamp to investigate insulin secretion. Since sexual dimorphic associations related to DRD2 polymorphisms have been previously reported, we also performed a gender-stratified analysis.

RESULTS

rs1800497 at the DRD2/ANKK1 locus was associated with a significantly increased risk for type 2 diabetes in women (odds ratio 1.14 (1.06-1.23); P = 4.1*10⁴) but not in men (odds ratio 1.00 (95% CI 0.93-1.07); P = 0.92) or the combined group. Although rs1800497 was not associated with insulin secretion, we did find another single nucleotide polymorphism in this locus, rs6275, to be associated with increased first-phase glucose-stimulated insulin secretion in women (P = 5.5*10⁴) but again not in men (P = 0.34).

CONCLUSION

The present data identify DRD2/ANKK1 as a potential sex-specific type 2 diabetes susceptibility gene.

Common variants in PCSK1 influence blood pressure and body mass index

Proprotein convertase subtilisin/kexin-type 1 (PCSK1) activates precursors pro-opiomelanocortin (POMC), proinsulin and prorenin. We investigated if common variants in the PCSK1 gene influence blood pressure and risk of hypertension. Additionally, we investigated the risk of obesity and type 2 diabetes (T2D). In the Rotterdam Study (RS1), a prospective, population-based cohort (n=5974), four single-nucleotide polymorphisms (rs10515237, rs6232, rs436321 and rs3792747) in PCSK1 were studied. Linear and Cox regression models served to analyze associations between variants and end points. Replication was performed in the Rotterdam Study Plus1 (RSPlus1, n=1895). Rs436321 was significantly associated with systolic and diastolic blood pressure and risk of hypertension (odds ratio (OR): 1.1-1.3; P<0.05 in both populations). Rs6232 was associated with body mass index (BMI) (P=0.007 and P=0.04 in RS1 and RSPlus1, respectively). In RSPlus1, heterozygotes for rs6232 had 1.5 times higher risk of obesity (OR: 1.46; 95% confidence interval: 1.04-2.03; P=0.03). We did not find significant associations of PCSK1 with fasting insulin levels and T2D. We found an association of genetic variation in the PCSK1 gene with blood pressure and hypertension. Furthermore, we replicated the association of PCSK1 with BMI and obesity. No relationship was found between PCSK1 variants and fasting insulin levels and T2D. Our findings suggest that genetic variation in PCSK1 may contribute to, at least, some of these interrelated disorders.

The association between plasma homocysteine levels and bone quality and bone mineral density parameters in older persons

INTRODUCTION

High plasma homocysteine levels have been associated with incident osteoporotic fractures, but the mechanisms underlying this association are still unknown. It has been hypothesized that homocysteine might interfere with collagen cross-linking in bone, thereby weakening bone structure. Therefore, we wanted to investigate whether plasma homocysteine levels are associated with bone quality parameters, rather than with bone mineral density.

METHODS

Cross-sectional data of the B-PROOF study (n=1227) and of two cohorts of the Rotterdam Study (RS-I (n=2850) and RS-II (n=2023)) were used. Data on bone mineral density of the femoral neck and lumbar spine were obtained in these participants using dual-energy X-ray assessment (DXA). In addition, participants of B-PROOF and RS-I underwent quantitative ultrasound measurement of the calcaneus, as a marker for bone quality. Multiple linear regression analysis was used to investigate the associations between natural-log transformed plasma levels of homocysteine and bone mineral density or ultrasound parameters.

RESULTS

Natural-log transformed homocysteine levels were inversely associated with femoral neck bone mineral density in the two cohorts of the Rotterdam Study (B=-0.025, p=0.004 and B=-0.024, p=0.024). In B-PROOF, no association was found. Pooled data analysis showed significant associations between homocysteine and bone mineral density at both femoral neck (B=-0.032, p=0.010) and lumbar spine (B=-0.098, p=0.021). Higher natural-log transformed homocysteine levels associated significantly with lower bone ultrasound attenuation in B-PROOF (B=-3.7, p=0.009) and speed of sound in both B-PROOF (B=-8.9, p=0.001) and RS-I (B=-14.5, p=0.003), indicating lower bone quality. Pooled analysis confirmed the association between homocysteine and SOS (B=-13.1, p=0.016). Results from ANCOVA-analysis indicate that differences in SOS and BUA between participants having a plasma homocysteine level above or below median correspond to 0.14 and 0.09 SD, respectively.

DISCUSSION

In this study, plasma levels of homocysteine were significantly inversely associated with both bone ultrasound parameters and with bone mineral density. However, the size of the associations seems to be of limited clinical relevance and may therefore not explain the previously observed association between plasma homocysteine and osteoporotic fracture incidence.

Large scale meta-analysis of urinary C-terminal telopeptide, serum cartilage oligomeric protein and matrix metalloprotease degraded type II collagen and their role in prevalence, incidence and progression of osteoarthritis

OBJECTIVE

To evaluate the role of three cartilage-derived biomarkers on osteoarthritis (OA): urinary C-terminal telopeptide (uCTX-II), serum cartilage oligomeric protein (sCOMP), and serum MMP degraded type II collagen (sC2M).

SUBJECTS AND METHODS

Samples from 3582 individuals from the Rotterdam Study, the Genetics osteoArthritis and Progression (GARP), the Chingford Study and the TwinsUK cohort were assayed using enzyme-linked immune sorbent assays. Log10 of concentration levels were correlated with risk of hip, hand and knee OA, hip and knee OA severity and incidence, and progression of knee OA, adjusting for age, gender and body mass index (BMI). Results were meta-analysed to assess overall significance.

RESULTS

After adjusting for covariates, sCOMP was associated with knee OA and hip and knee OA incidence. Furthermore, sC2M was associated with knee OA incidence and progression. After adjustment for multiple tests (Bonferroni P < 0.002) only the association between sCOMP and knee OA remained significant (odds ratio (OR) = 3.26 (95%CI 1.63-10.1) P = 0.0008 for each standard deviation (SD) increase in biomarker levels). Levels of uCTX-II were significantly associated with risk of hand, hip and knee OA, progression and incidence of knee OA. A receiver operating characteristics (ROC) analysis showed a consistent improvement in prediction of knee OA progression from an average area under the curve (AUC) is 0.646 for age, sex and BMI alone to an AUC = 0.668 including uCTX-II for prediction.

CONCLUSIONS

uCTX-II is the most informative biochemical marker for prediction of OA. Both sCOMP and C2M showed some association with OA, thus indicating that they are descriptive of disease activity.

Infant diet and metabolic outcomes in school-age children. The Generation R Study

BACKGROUND

Breastfeeding duration is associated with the risks of cardio-metabolic diseases in adulthood. We examined the associations of infant feeding patterns with metabolic outcomes in children and whether any association was explained by family-based socio-demographic, maternal lifestyle-related or childhood factors.

SUBJECTS/METHODS

We performed a population-based prospective cohort study in 3417 children to examine the associations of breastfeeding duration and exclusivity and age at introduction of solid foods with blood levels of lipids, insulin and C-peptide and risk of clustering of cardio-metabolic risk factors at the median age of 6.0 years (90% range 5.7-6.8).

RESULTS

We observed that, in the models only adjusted for child's age and sex, ever breastfeeding was not associated with childhood blood levels of lipids but was associated with higher insulin and C-peptide concentrations (P-value<0.05). Breastfeeding duration and exclusivity were not consistently associated with metabolic outcomes. Early introduction of solid foods was associated with higher levels of total cholesterol (P-value<0.05) but not with high-density lipoprotein and low-density lipoprotein cholesterol, triglycerides and insulin levels. Shorter breastfeeding duration and exclusive breastfeeding were associated with increased risks of clustering of cardio-metabolic risk factors. After additional adjustment for family, maternal and childhood factors, none of these associations remained significant.

CONCLUSIONS

In conclusion, we found no consistent associations of infant feeding patterns with metabolic outcomes at school age, after taking into account family-based socio-demographic, maternal lifestyle-related or childhood factors. Whether infant diet composition influences metabolic outcomes in later life should be further studied.

Arterial stiffness and influences of the metabolic syndrome: a cross-countries study

Specific clusters of metabolic syndrome (MetS) components impact differentially on arterial stiffness, indexed as pulse wave velocity (PWV). Of note, in several population-based studies participating in the MARE (Metabolic syndrome and Arteries REsearch) Consortium the occurrence of specific clusters of MetS differed markedly across Europe and the US. The aim of the present study was to investigate whether specific clusters of MetS are consistently associated with stiffer arteries in different populations. We studied 20,570 subjects from 9 cohorts representing 8 different European countries and the US participating in the MARE Consortium. MetS was defined in accordance with NCEP ATPIII criteria as the simultaneous alteration in ≥3 of the 5 components: abdominal obesity (W), high triglycerides (T), low HDL cholesterol (H), elevated blood pressure (B), and elevated fasting glucose (G). PWV measured in each cohort was "normalized" to account for different acquisition methods. MetS had an overall prevalence of 24.2% (4985 subjects). MetS accelerated the age-associated increase in PWV levels at any age, and similarly in men and women. MetS clusters TBW, GBW, and GTBW are consistently associated with significantly stiffer arteries to an extent similar or greater than observed in subjects with alteration in all the five MetS components--even after controlling for age, sex, smoking, cholesterol levels, and diabetes mellitus--in all the MARE cohorts. In conclusion, different component clusters of MetS showed varying associations with arterial stiffness (PWV).

Dissecting the relationship between high-sensitivity serum C-reactive protein and increased fracture risk: the Rotterdam Study

Serum high-sensitivity C-reactive protein (CRP) is an inflammatory biomarker. We investigated the relationship between CRP and bone health in the Rotterdam Study. Serum high-sensitivity CRP was associated with fracture risk and lower femoral neck bending strength. Mendelian randomization analyses did not yield evidence for this relationship being causal.

INTRODUCTION

Inflammatory diseases are associated with bone pathology, reflected in a higher fracture risk. Serum high-sensitivity CRP is an inflammatory biomarker. We investigated the relationship between CRP and bone mineral density (BMD), hip bone geometry, and incident fractures in the Rotterdam Study, a prospective population-based cohort.

METHODS

At baseline, serum high-sensitivity CRP was measured. A weighted genetic risk score was compiled for CRP based on published studies (29 polymorphisms; Illumina HumanHap550 Beadchip genotyping and HapMap imputation). Regression models were reported per standard deviation increase in CRP adjusted for sex, age, and BMI. Complete data was available for 6,386 participants, of whom 1,561 persons sustained a fracture (mean follow-up, 11.6 years).

RESULTS

CRP was associated with a risk for any type of fracture [hazard ratio (HR) = 1.06; 95 % confidence interval (CI), 1.02-1.11], hip fractures (HR = 1.09; 1.02-1.17) and vertebral fractures [odds ratio (OR) = 1.34; 1.14-1.58]. An inverse relationship between CRP levels and section modulus (-0.011 cm(3); -0.020 to -0.003 cm(3)) was observed. The combined genetic risk score of CRP single nucleotide polymorphisms (SNPs) was associated with serum CRP levels (p = 9 × 10(-56)), but not with fracture risk (HR = 1.00; 0.99-1.00; p = 0.23).

CONCLUSIONS

Serum high-sensitivity CRP is associated with fracture risk and lower bending strength. Mendelian randomization analyses did not yield evidence for this relationship being causal. Future studies might reveal what factors truly underlie the relationship between CRP and fracture risk.

Fetal sex specific differences in human placentation: a prospective cohort study

INTRODUCTION

Our objective was to assess fetal sex specific differences in first trimester placental biomarkers of both physiological and pathological pregnancies and their interaction with environmental influences. This study is embedded in the Generation R Study, a prospective cohort study.

METHODS

Only live singleton births were included. Linear regression was performed to assess the effect of sex on first trimester placental biomarkers. Interaction analyses were performed to assess interaction of fetal sex with environmental influences. First trimester soluble fms-like tyrosine kinase (s-Flt1), placental growth factor (PLGF), plasminogen activator inhibitor (PAI-2) and homocysteine levels were assessed.

RESULTS

Significant fetal sex specific differences in placental biomarkers were observed. S-Flt1, PAI-2 and PLGF log transformated concentrations were 0.08 ng/mL (95% CI 0.05; 0.11), 0.07 ng/mL (95% CI 0.06; 0.09) and 0.04 pg/mL (95% CI 0.01; 0.06) higher in case of female as compared to male placentas. In pregnancies complicated by pre-eclampsia (PE), preterm birth (PTB) or a newborn being small for gestational age (SGA) no fetal sex specific differences were observed. Interaction analyses suggest that concentrations of s-Flt1, PLGF and PAI-2 decrease in male placentas in the case of hyperhomocysteinemia but remain equal in female placentas.

DISCUSSION

Fetal sex affects early placentation processes with discrepancies regarding pregnancies complicated by PE, PTB or a newborn being SGA. This suggests that other mechanisms causing these complications may dominate the fetal sex effect. The differences concerning homocysteine suggest that fetal sex dependent placental gene-environment interactions exist.

CONCLUSION

Fetal sex specific differences in placental biomarkers exist.

Utilization patterns of antidepressants between 1991 and 2011 in a population-based cohort of middle-aged and elderly

BACKGROUND

In middle-aged and older patients in whom antidepressant use increased in last decades, patterns of use might be of concern The objective of this study was to investigate the patterns of prevalence, incidence and duration of antidepressant use in an ageing population.

METHODS

All participants (aged>45 years) from the population-based Rotterdam Study were followed from January 1st 1991 until death, loss to follow-up, or end of the study period (December 31st 2011). Antidepressant drug dispensing, based on pharmacy records, were subdivided into Tricyclic Antidepressants (TCAs), Selective Serotonin Reuptake Inhibitors (SSRIs) and other antidepressants. One-year prevalence, 5-year incidence and duration of antidepressant use were calculated.

RESULTS

Yearly prevalence of antidepressant use increased from 3.9% in 1991 to 8.3% of the population in 2011. The increase in SSRI use was 5.8-fold, whereas use of other antidepressants doubled and TCA use remained stable over time. Incidence of all antidepressants decreased from 23.9 to 14.2 per 1000 person-years between 1992 and 2011. The duration of a first treatment episode increased over time.

CONCLUSION

Despite the prevalence of antidepressant use increased over time, incidence did not, which is most likely explained by a longer treatment duration and recurrent episodes.

Drug-gene interactions and the search for missing heritability: a cross-sectional pharmacogenomics study of the QT interval

Variability in response to drug use is common and heritable, suggesting that genome-wide pharmacogenomics studies may help explain the 'missing heritability' of complex traits. Here, we describe four independent analyses in 33 781 participants of European ancestry from 10 cohorts that were designed to identify genetic variants modifying the effects of drugs on QT interval duration (QT). Each analysis cross-sectionally examined four therapeutic classes: thiazide diuretics (prevalence of use=13.0%), tri/tetracyclic antidepressants (2.6%), sulfonylurea hypoglycemic agents (2.9%) and QT-prolonging drugs as classified by the University of Arizona Center for Education and Research on Therapeutics (4.4%). Drug-gene interactions were estimated using covariable-adjusted linear regression and results were combined with fixed-effects meta-analysis. Although drug-single-nucleotide polymorphism (SNP) interactions were biologically plausible and variables were well-measured, findings from the four cross-sectional meta-analyses were null (Pinteraction>5.0 × 10(-8)). Simulations suggested that additional efforts, including longitudinal modeling to increase statistical power, are likely needed to identify potentially important pharmacogenomic effects.

Parental smoking during pregnancy and total and abdominal fat distribution in school-age children: the Generation R Study

OBJECTIVE

Fetal smoke exposure may influence growth and body composition later in life. We examined the associations of maternal and paternal smoking during pregnancy with total and abdominal fat distribution in school-age children.

METHODS

We performed a population-based prospective cohort study among 5243 children followed from early pregnancy onward in the Netherlands. Information about parental smoking was obtained by questionnaires during pregnancy. At the median age of 6.0 years (90% range: 5.7-7.4), we measured anthropometrics, total fat and android/gynoid fat ratio by dual-energy X-ray absorptiometry, and preperitoneal and subcutaneous abdominal fat were measured by ultrasound.

RESULTS

The associations of maternal smoking during pregnancy were only present among girls (P-value for sex interaction<0.05). Compared with girls from mothers who did not smoke during pregnancy, those from mothers who smoked during the first trimester only had a higher android/gynoid fat ratio (difference 0.23 (95% confidence interval (CI): 0.09-0.37) s.d. scores (SDS). Girls from mothers who continued smoking throughout pregnancy had a higher body mass index (difference: 0.24 (95% CI: 0.14-0.35) SDS), total fat mass (difference: 0.23 (95% CI: 0.14-0.33) SDS), android/gynoid fat ratio (difference: 0.34 (95% CI: 0.22-0.46) SDS), subcutaneous abdominal fat (difference: 0.22 (95% CI: 0.11-0.33) SDS) and preperitoneal abdominal fat (difference: 0.20 (95% CI: 0.08-0.31) SDS). Similar associations with body fat distribution outcomes were observed for paternal smoking during pregnancy. Both continued maternal and paternal smoking during pregnancy may be associated with an increased risk of childhood overweight. The corresponding odds ratios were 1.19 (95% CI: 0.98-1.46) and 1.32 (1.10-1.58), respectively.

CONCLUSIONS

Maternal and paternal smoking during pregnancy are associated with an adverse body and abdominal fat distribution and increased risk of overweight in children. Similar effects of maternal and paternal smoking suggest that direct intrauterine mechanisms and common family-based lifestyle-related factors explain the associations.

Development and validation of an ankle brachial index risk model for the prediction of cardiovascular events

BACKGROUND

The ankle brachial index (ABI) is related to risk of cardiovascular events independent of the Framingham risk score (FRS). The aim of this study was to develop and evaluate a risk model for cardiovascular events incorporating the ABI and FRS.

DESIGN

An analysis of participant data from 18 cohorts in which 24,375 men and 20,377 women free of coronary heart disease had ABI measured and were followed up for events.

METHODS

Subjects were divided into a development and internal validation dataset and an external validation dataset. Two models, comprising FRS and FRS + ABI, were fitted for the primary outcome of major coronary events.

RESULTS

In predicting events in the external validation dataset, C-index for the FRS was 0.672 (95% CI 0.599 to 0.737) in men and 0.578 (95% CI 0.492 to 0.661) in women. The FRS + ABI led to a small increase in C-index in men to 0.685 (95% CI 0.612 to 0.749) and large increase in women to 0.690 (95% CI 0.605 to 0.764) with net reclassification improvement (NRI) of 4.3% (95% CI 0.0 to 7.6%, p = 0.050) and 9.6% (95% CI 6.1 to 16.4%, p < 0.001), respectively. Restricting the FRS + ABI model to those with FRS intermediate 10-year risk of 10 to 19% resulted in higher NRI of 15.9% (95% CI 6.1 to 20.6%, p < 0.001) in men and 23.3% (95% CI 13.8 to 62.5%, p = 0.002) in women. However, incorporating ABI in an improved newly fitted risk factor model had a nonsignificant effect: NRI 2.0% (95% CI 2.3 to 4.2%, p = 0.567) in men and 1.1% (95% CI 1.9 to 4.0%, p = 0.483) in women.

CONCLUSIONS

An ABI risk model may improve prediction especially in individuals at intermediate risk and when performance of the base risk factor model is modest.

Meta-analysis of 74,046 individuals identifies 11 new susceptibility loci for Alzheimer's disease

Eleven susceptibility loci for late-onset Alzheimer's disease (LOAD) were identified by previous studies; however, a large portion of the genetic risk for this disease remains unexplained. We conducted a large, two-stage meta-analysis of genome-wide association studies (GWAS) in individuals of European ancestry. In stage 1, we used genotyped and imputed data (7,055,881 SNPs) to perform meta-analysis on 4 previously published GWAS data sets consisting of 17,008 Alzheimer's disease cases and 37,154 controls. In stage 2, 11,632 SNPs were genotyped and tested for association in an independent set of 8,572 Alzheimer's disease cases and 11,312 controls. In addition to the APOE locus (encoding apolipoprotein E), 19 loci reached genome-wide significance (P < 5 × 10(-8)) in the combined stage 1 and stage 2 analysis, of which 11 are newly associated with Alzheimer's disease.

TRPV4 deficiency causes sexual dimorphism in bone metabolism and osteoporotic fracture risk

We explored the role of transient receptor potential vanilloid 4 (TRPV4) in murine bone metabolism and association of TRPV4 gene variants with fractures in humans. Urinary and histomorphometrical analyses demonstrated reduced osteoclast activity and numbers in male Trpv4(-/-) mice, which was confirmed in bone marrow-derived osteoclast cultures. Osteoblasts and bone formation as shown by serum procollagen type 1 amino-terminal propeptide and histomorphometry, including osteoid surface, osteoblast and osteocyte numbers were not affected in vivo. Nevertheless, osteoblast differentiation was enhanced in Trpv4(-/-) bone marrow cultures. Cortical and trabecular bone mass was 20% increased in male Trpv4(-/-) mice, compared to sex-matched wild type (Trpv4(+/+)) mice. However, at the same time intracortical porosity was increased and bone matrix mineralization was reduced. Together, these lead to a maximum load, stiffness and work to failure of the femoral bone, which were not different compared to Trpv4(+/+) mice, while the bone material was less resistant to stress and less elastic. The differential impacts on these determinants of bone strength were likely responsible for the lack of any changes in whole bone strength in the Trpv4(-/-) mice. None of these skeletal parameters were affected in female Trpv4(-/-) mice. The T-allele of rs1861809 SNP in the TRPV4 locus was associated with a 30% increased risk (95% CI: 1.1-1.6; p=0.013) for non-vertebral fracture risk in men, but not in women, in the Rotterdam Study. Meta-analyses with the population-based LASA study confirmed the association with non-vertebral fractures in men. This was lost when the non-population-based studies Mr. OS and UFO were included. In conclusion, TRPV4 is a male-specific regulator of bone metabolism, a determinant of bone strength, and a potential risk predictor for fractures through regulation of bone matrix mineralization and intra-cortical porosity. This identifies TRPV4 as a unique sexually dimorphic therapeutic and/or diagnostic candidate for osteoporosis.

Association of lumbar disc degeneration with osteoporotic fractures; the Rotterdam study and meta-analysis from systematic review

OBJECTIVE

To investigate the relation between lumbar disc degeneration (LDD) and all type of osteoporotic (OP) fractures including vertebral.

METHODS

This study is part of the Rotterdam study, a large prospective population-based cohort study among men and women aged 55years and over. In 2819 participants spine radiographs were scored for LDD (osteophytes and disc space narrowing (DSN)) from L1 till S1, using the Lane atlas. Osteoporotic (OP) fracture data were collected and verified by specialists during 12.8years. We considered two types of vertebral fractures (VFx): Clinical VFx (symptomatic fractures recorded by medical practitioners) and Radiographic VFx (using the McCloskey-Kanis method). Meta-analysis of published studies reporting an association of LDD features and VFx was performed. Differences in Bone Mineral Density (BMD) between participants with and without LDD features were analyzed using ANOVA. Risk of OP-fractures was analyzed using Cox regression.

RESULTS

In a total of 2385 participants, during 12.8years follow-up, 558 suffered an OP-fracture. Subjects with LDD had an increased OP fracture risk compared to subjects without LDD (HR: 1.29, CI: 1.04-1.60). LDD-cases have between 0.3 and 0.72 standard deviations more BMD than non-cases in all analyzed regions including total body BMD and skull BMD (P<0.001). Only males with LDD had increased risk for OP-fractures compared to males without LDD (adjusted-HR: 1.80, 95%CI: 1.20-2.70, P=0.005). The risk was also higher for VFx in males (HR: 1.64, CI: 1.03-2.60, P: 0.04). The association LDD-OP-fractures in females was lower and not significant (adjusted-HR: 1.08, 95%CI: 0.82-1.41). Meta-analyses showed that the risk of VFx in subjects with LDD has been studied only in women and there is not enough evidence to confidently analyze the relationship between LDD-features (DSN or/and OPH) and VFx due to low power and heterogeneity in phenotype definition in the collected studies.

CONCLUSIONS

Male subjects with LDD have a higher osteoporotic fracture risk, in spite of systemically higher BMD.

Ethnicity is a strong predictor for Helicobacter pylori infection in young women in a multi-ethnic European city

BACKGROUND AND AIM

At the same time that Helicobacter pylori prevalence is declining in Western countries, immigrants from developing countries with high H. pylori prevalence have settled in Western urban areas. Actual epidemiological data on H. pylori in a migrant community may help in realizing a more selective approach to assess H. pylori-related diseases. We aimed to define H. pylori prevalence as well as risk groups for H. pylori in a cohort of young women living in a multi-ethnic European city.

METHODS

We measured Immunoglobulin G (IgG) anti-H. pylori and CagA-antibodies in serum of pregnant women included in a population-based prospective cohort study, the Generation R study. Information on demographics and socioeconomic status was collected by questionnaires. Chi-square and logistic regression were used.

RESULTS

In total, 3146 (46%) of the 6837 tested women (mean age 29.7 ± 5.3) were H. pylori-positive and 1110 (35%) of them were CagA-positive. The H. pylori prevalence in Dutch women was 24%, which was significantly lower than in non-Dutch women (64%; P < 0.001). In particular, H. pylori positivity was found in 92% of Moroccan (odds ratio 19.2; 95% confidence interval 11.8-32.0), 80% of Cape Verdean (7.6; 5.0-11.5), 81% of Turkish (9.0; 6.7-12.1), 60% of Dutch Antillean (3.3; 2.3-4.7), and 58% of Surinamese women (3.0; 2.3-3.8). Among H. pylori-positive Dutch subjects, 19% were CagA-positive compared with 40% of the non-Dutch subjects (P < 0.001).

CONCLUSIONS

Despite a general trend of declining prevalence in Western countries, H. pylori remains highly prevalent in migrant communities, which may constitute target groups for screening and eradication to prevent H. pylori-related diseases.

Fertility treatment, twin births, and unplanned pregnancies in women with eating disorders: findings from a population-based birth cohort

Objective

To investigate fertility treatment, twin births, and unplanned pregnancies in pregnant women with eating disorders in a population-based sample.

Design

A longitudinal population-based birth cohort (Generation R).

Setting

Rotterdam, the Netherlands.

Sample

Women from the Generation R study who reported a history of (recent or past) anorexia nervosa (n = 160), bulimia nervosa (n = 265), or both (n = 130), and a history of psychiatric disorders other than eating disorders (n = 1396) were compared with women without psychiatric disorders (n = 4367).

Methods

Women were compared on the studied outcomes using logistic regression. We performed crude and adjusted analyses (adjusting for relevant confounding factors).

Main outcome measures

Fertility treatment, twin births, unplanned pregnancies, and women's feelings towards unplanned pregnancies.

Results

Relative to women without psychiatric disorders, women with bulimia nervosa had increased odds (odds ratio, OR, 2.3; 95% confidence interval, 95% CI, 1.1–5.2) of having undergone fertility treatment. Women with all eating disorders had increased odds of twin births (anorexia nervosa, OR 2.7, 95% CI 1.0–7.7; bulimia nervosa, OR 2.7, 95% CI 1.1–6.6; anorexia and bulimia nervosa, OR 3.795% CI 1.3–10.7). Anorexia nervosa was associated with increased odds of unplanned pregnancies (OR 1.8, 95% CI 1.2–2.6) and mixed feelings about these pregnancies (adjusted OR 5.0, 95% CI 1.7–14.4). Pre-pregnancy body mass index did not explain the observed associations.

Conclusions

Eating disorders are associated with increased odds of receiving fertility treatment and twin births. Women with anorexia nervosa were more likely to have an unplanned pregnancy and have mixed feelings about the unplanned pregnancy. Fertility treatment specialists should be aware that both active and past eating disorders (both anorexia nervosa and bulimia nervosa) might underlie fertility problems.

The contribution of hip geometry to the prediction of hip osteoarthritis

OBJECTIVE

To determine how well measures of hip geometry can predict radiological incident hip osteoarthritis (HOA) compared to well known clinical risk factors.

DESIGN

The study population is part of the Rotterdam Study, a prospective population-based cohort. Baseline pelvic radiographs were used to measure hip geometry by two methods: Statistical Shape Models (SSM) and predefined geometry parameters (PGPs). Incident HOA (Kellgren and Lawrence (KL) ≥ 2) was assessed in 688 participants after 6.5 years without radiographic HOA at baseline. The ability to predict HOA was quantified using the area under the Receiver Operating Characteristics (ROC) curve (AUC).

RESULTS

Comparison of the two methods showed that both contain information that is not captured by the other method. At 6.5 years follow-up 132 hips had incident HOA. Five PGPs (Wiberg angle, Neck Width (NW), Pelvic Width (PW), Hip Axis Length (HAL) and Triangular Index (TI)) and two SSM (modes 5 and 9) were significant predictors of HOA (P = 0.007). Hip geometry added 7% to the prediction obtained by clinical risk factors (AUC = 0.67 (geometry), 0.66 (gender, age, Body Mass Index (BMI)) and combining both: AUC = 0.73, respectively). Mode 12 (associated with position of the femoral head in acetabulum) and Wiberg angle were predictors of HOA in participants without radiological signs at baseline (KL = 0). Although the strength of the prediction decreased for all variables at a longer follow-up, the contribution of hip geometry was still significant (P = 0.01).

CONCLUSIONS

Hip geometry has a moderate ability to predict HOA in participants with and without initial signs of osteoarthritis (OA), similar to and largely independent of the predictive value of clinical risk factors.

Parental anthropometrics, early growth and the risk of overweight in pre-school children: the Generation R Study

BACKGROUND

There are limited data regarding the associations of both maternal and paternal anthropometrics with longitudinally measured post-natal growth measures in early childhood.

OBJECTIVE

To assess the associations of maternal and paternal anthropometrics with growth characteristics and the risk of overweight in pre-school children.

STUDY DESIGN

Population-based prospective cohort study from early foetal life onwards in the Netherlands.

METHODS

Maternal pre-pregnancy anthropometrics and gestational weight gain, and paternal anthropometrics were related to foetal and post-natal growth measures and the risk of overweight until the age of 4 years. Analyses were based on 5674 mothers, fathers and their children.

RESULTS

Both pre-pregnancy maternal and paternal height, weight and body mass index were associated with corresponding foetal and post-natal anthropometric measures. Maternal body mass index had a significantly stronger effect on childhood body mass index than paternal body mass index. As compared to children from parents with normal body mass index, children from two obese parents had an increased risk of overweight at the age of 4 years (odds ratio 6.52 (95% confidence interval 3.44, 12.38). Maternal gestational weight gain was only among mothers with normal body mass index associated with body mass index and the risk of overweight in the children.

CONCLUSION

Maternal and paternal anthropometrics affect early growth in pre-school children differently. Gestational weight gain in mothers without overweight and obesity is related to the risk of overweight in early childhood.

Prediction model for knee osteoarthritis incidence, including clinical, genetic and biochemical risk factors

OBJECTIVE

To develop and validate a prognostic model for incident knee osteoarthritis (KOA) in a general population and determine the value of different risk factor groups to prediction.

METHODS

The prognostic model was developed in 2628 individuals from the Rotterdam Study-I (RS-I). Univariate and multivariate analyses were performed for questionnaire/easily obtainable variables, imaging variables, genetic and biochemical markers. The extended multivariate model was tested on discrimination (receiver operating characteristic curve and area under the curve (AUC)) in two other population-based cohorts: Rotterdam Study-II and Chingford Study.

RESULTS

In RS-I, there was moderate predictive value for incident KOA based on the genetic score alone in subjects aged <65 years (AUC 0.65), while it was only 0.55 for subjects aged ≥65 years. The AUC for gender, age and body mass index (BMI) in prediction for KOA was 0.66. Addition of the questionnaire variables, genetic score or biochemical marker urinary C-terminal cross-linked telopeptide of type II collagen to the model did not change the AUC. However, when adding the knee baseline KL score to the model the AUC increased to 0.79. Applying external validation, similar results were observed in the Rotterdam Study-II and the Chingford Study.

CONCLUSIONS

Easy obtainable 'Questionnaire' variables, genetic markers, OA at other joint sites and biochemical markers add only modestly to the prediction of KOA incidence using age, gender and BMI in an elderly population. Doubtful minor radiographic degenerative features in the knee, however, are a very strong predictor of future KOA. This is an important finding, as many radiologists do not report minor degenerative changes in the knee.

Association of heat shock proteins with all-cause mortality

Experimental mild heat shock is widely known as an intervention that results in extended longevity in various models along the evolutionary lineage. Heat shock proteins (HSPs) are highly upregulated immediately after a heat shock. The elevation in HSP levels was shown to inhibit stress-mediated cell death, and recent experiments indicate a highly versatile role for these proteins as inhibitors of programmed cell death. In this study, we examined common genetic variations in 31 genes encoding all members of the HSP70, small HSP, and heat shock factor (HSF) families for their association with all-cause mortality. Our discovery cohort was the Rotterdam study (RS1) containing 5,974 participants aged 55 years and older (3,174 deaths). We assessed 4,430 single nucleotide polymorphisms (SNPs) using the HumanHap550K Genotyping BeadChip from Illumina. After adjusting for multiple testing by permutation analysis, three SNPs showed evidence for association with all-cause mortality in RS1. These findings were followed in eight independent population-based cohorts, leading to a total of 25,007 participants (8,444 deaths). In the replication phase, only HSF2 (rs1416733) remained significantly associated with all-cause mortality. Rs1416733 is a known cis-eQTL for HSF2. Our findings suggest a role of HSF2 in all-cause mortality.

Common carotid intima-media thickness does not add to Framingham risk score in individuals with diabetes mellitus: the USE-IMT initiative

AIMS/HYPOTHESIS

The aim of this work was to investigate whether measurement of the mean common carotid intima-media thickness (CIMT) improves cardiovascular risk prediction in individuals with diabetes.

METHODS

We performed a subanalysis among 4,220 individuals with diabetes in a large ongoing individual participant data meta-analysis involving 56,194 subjects from 17 population-based cohorts worldwide. We first refitted the risk factors of the Framingham heart risk score on the individuals without previous cardiovascular disease (baseline model) and then expanded this model with the mean common CIMT (CIMT model). The absolute 10 year risk for developing a myocardial infarction or stroke was estimated from both models. In individuals with diabetes we compared discrimination and calibration of the two models. Reclassification of individuals with diabetes was based on allocation to another cardiovascular risk category when mean common CIMT was added.

RESULTS

During a median follow-up of 8.7 years, 684 first-time cardiovascular events occurred among the population with diabetes. The C statistic was 0.67 for the Framingham model and 0.68 for the CIMT model. The absolute 10 year risk for developing a myocardial infarction or stroke was 16% in both models. There was no net reclassification improvement with the addition of mean common CIMT (1.7%; 95% CI -1.8, 3.8). There were no differences in the results between men and women.

CONCLUSIONS/INTERPRETATION

There is no improvement in risk prediction in individuals with diabetes when measurement of the mean common CIMT is added to the Framingham risk score. Therefore, this measurement is not recommended for improving individual cardiovascular risk stratification in individuals with diabetes.