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The COllaborative project of Development of Anthropometrical measures in Twins (CODATwins) project is a large international collaborative effort to analyze individual-level phenotype data from twins in multiple cohorts from different environments. The main objective is to study factors that modify genetic and environmental variation of height, body mass index (BMI, kg/m2) and size at birth, and additionally to address other research questions such as long-term consequences of birth size. The project started in 2013 and is open to all twin projects in the world having height and weight measures on twins with information on zygosity. Thus far, 54 twin projects from 24 countries have provided individual-level data. The CODATwins database includes 489,981 twin individuals (228,635 complete twin pairs). Since many twin cohorts have collected longitudinal data, there is a total of 1,049,785 height and weight observations. For many cohorts, we also have information on birth weight and length, own smoking behavior and own or parental education. We found that the heritability estimates of height and BMI systematically changed from infancy to old age. Remarkably, only minor differences in the heritability estimates were found across cultural–geographic regions, measurement time and birth cohort for height and BMI. In addition to genetic epidemiological studies, we looked at associations of height and BMI with education, birth weight and smoking status. Within-family analyses examined differences within same-sex and opposite-sex dizygotic twins in birth size and later development. The CODATwins project demonstrates the feasibility and value of international collaboration to address gene-by-exposure interactions that require large sample sizes and address the effects of different exposures across time, geographical regions and socioeconomic status.
The objective of this work was to describe treatment-emergent sexual dysfunction (TESD) and tolerability following a switch from selective serotonin reuptake inhibitor (SSRI: citalopram, paroxetine, or sertraline) monotherapy to vortioxetine or escitalopram monotherapy in adults with well-treated major depressive disorder (MDD) and SSRI-induced sexual dysfunction.
Data were analyzed from the primary study, an 8-week, randomized, double-blind, head-to-head study in which participants with well-treated depressive symptoms but experiencing TESD with SSRIs were directly switched to flexible doses (10/20 mg) of vortioxetine or escitalopram. Sexual functioning was assessed by the Changes in Sexual Functioning Questionnaire-14 (CSFQ-14), efficacy by the Montgomery–Åsberg Depression Rating Scale scores (MADRS) and Clinicians Global Impression of Severity/Improvement (CGI-S/CGI-I), and tolerability by adverse events. Efficacy and tolerability were assessed by pre-switch SSRI therapy where possible, and by participant characteristics.
Greater improvements in TESD were seen in the vortioxetine compared with escitalopram groups based on: participant demographics (≤45 years, women; P = 0.045), prior SSRI treatment (P = 0.044), number of prior major depressive episodes (MDEs) (1–3; P = 0.001), and duration of prior SSRI therapy (>1 year; P = 0.001). Prior SSRI treatment did not appear to influence the incidence or severity of TEAEs, except for nausea. Regardless of prior SSRI, both treatments maintained antidepressant efficacy after 8 weeks.
Results suggest that vortioxetine is a safe and effective switch therapy for treating SSRI-induced sexual dysfunction in adults with well-treated MDD. Also, improvement in sexual dysfunction with vortioxetine or escitalopram may be influenced by prior SSRI usage, sex, age, and history of MDEs.
Investigations into an outbreak of foodborne disease attempt to identify the source of illness as quickly as possible. Population-based reference values for food consumption can assist in investigation by providing comparison data for hypothesis generation and also strengthening the evidence associated with a food product through hypothesis testing. In 2014–2015 a national phone survey was conducted in Canada to collect data on food consumption patterns using a 3- or 7-day recall period. The resulting food consumption values over the two recall periods were compared. The majority of food products did not show a significant difference in the consumption over 3 days and 7 days. However, comparison of reference values from the 3-day recall period to data from an investigation into a Salmonella Infantis outbreak was shown to support the conclusion that chicken was the source of the outbreak whereas the reference values from a 7-day recall did not support this finding. Reference values from multiple recall periods can assist in the hypothesis generation and hypothesis testing phase of foodborne outbreak investigations.
Buprenorphine (BUP)/samidorphan (SAM) combination is an opioid system modulator being investigated as an adjunctive treatment for major depressive disorder (MDD). BUP/SAM is a fixed-dose combination of BUP, a partial µ-opioid receptor agonist and κ-opioid receptor antagonist, and SAM, a µ-opioid receptor antagonist added to address the abuse and dependence potential of BUP.1,2
We assessed the effects of SAM on the abuse potential of BUP in the BUP/SAM combination in two ways: (1) a human abuse potential (HAP) study in volunteers; and (2) an evaluation of the clinical experience across studies of patients with MDD.
Study 212 (ClinicalTrials.gov ID: NCT02413281) was a HAP study in nondependent, recreational, adult opioid users. Following a qualification period, participants were randomized to 6 treatments in a blinded, crossover design: placebo (PBO), BUP/SAM at the target therapeutic dose (BUP/SAM 2mg/2mg), at 8mg/8mg and 16mg/16mg , and BUP alone (8mg and 16mg). The primary endpoint was maximum effect (Emax) for “At The Moment” Drug Liking Visual Analog Scale (VAS).
The clinical program for BUP/SAM included 4 PBO-controlled studies of patients with MDD (n=961). Pooled safety data were evaluated for adverse events (AEs) that may be associated with abuse, dependence, or withdrawal, as well as for objective signs of withdrawal with the Clinical Opioid Withdrawal Scale (COWS).
In Study 212 (n=38), Emax Drug Liking VAS scores for the BUP/SAM 2mg/2mg dose were similar to those for PBO (median within-subject difference [90% CI]: 2.5 [0.0–9.0]). Emax Drug Liking VAS scores for all BUP/SAM dose groups, including supratherapeutic doses, were significantly lower than those observed for either of the BUP doses. The supratherapeutic doses of BUP/SAM (8mg/8mg and 16mg/16mg) had higher Emax Drug Liking VAS scores than PBO, but the differences were small.
In the MDD controlled studies, the incidence of euphoria-related AEs was low for BUP/SAM 2mg/2mg and PBO (1.6% vs 0.2%, respectively) and there was no evidence of abuse or dependence behavior. Euphoria-related events typically occurred with treatment initiation and resolved with continued treatment. There was minimal evidence of withdrawal by reported AEs or COWS assessment.
These findings indicate that SAM mitigates the abuse potential of BUP in the BUP/SAM combination.
Tardive dyskinesia (TD) is a hyperkinetic movement disorder associated with antipsychotic treatment. RE KINECT (NCT03062033), a real-world study of outpatients prescribed antipsychotics, was designed to identify the presence of possible TD and characterize the impact of involuntary movements on functioning and quality of life. Data from RE-KINECT were used to compare the impact of possible TD in patients with schizophrenia/schizoaffective disorder [SZD] versus mood/other psychiatric disorders [Mood].
Adults with ≥3months of lifetime exposure to antipsychotics and ≥1 psychiatric disorder were recruited. The presence of possible TD was based on clinicians’ observation of involuntary movements in 4 body regions (head, trunk, upper extremities, and lower extremities). Baseline outcomes included demographics, medication history, location/severity of abnormal movements, impact of abnormal movements on daily activities, the Sheehan Disability Scale (SDS), and the EuroQoL 5-Dimensional questionnaire (EQ-5D-5L).
Of 204 patients with clinician-confirmed possible TD, 111 (54.4%) had a SZD diagnosis and 93 (45.6%) had a mood/other psychiatric diagnosis. Significant differences found between groups (Mood vs SZD) included: mean age (56.9 vs 52.7 years; P=0.0263); male sex (33.3% vs 62.2%; P<0.0001); African-American race (7.5% vs 26.1%; P=0.0005); mean lifetime exposure to antipsychotics (9.5 vs 19.5 years; P<0.0001); and percentage of patients currently taking ≥2 psychiatric medications (93.5% vs 79.3%; P=0.0093). Based on clinician observation, there were no significant differences between diagnosis groups in the number of body regions impacted by abnormal movements, maximum severity score across all 4 regions, or patient awareness of possible TD. Over 30% of patients in both groups reported that involuntary movements had “some” or “a lot” of impact on their ability to continue usual activities, be productive, and socialize. No significant differences between the diagnosis groups (Mood vs SZD) were found for mean SDS total score (12.8 vs 10.8), SDS domain scores (work/school [4.1 vs 4.2], social life [4.3 vs 3.7], family life [4.1 vs 3.5]), EQ-5D-5L utility score (0.68 vs 0.74), or EQ-5D-5L health state VAS (64.8 vs 68.5).
In this cohort of outpatients with possible TD, those with Mood disorders were more likely to be older, female, and white than patients with SZD. The ability to function and quality of life were equally impaired in both groups. Further studies on the impact of TD are needed.
Funding Acknowledgements: Neurocrine Biosciences, Inc.
The efficacy of valbenazine (INGREZZA) in tardive dyskinesia (TD) was demonstrated in placebo-controlled clinical trials, based on the Abnormal Involuntary Movement Scale (AIMS) total score (sum of items 1-7). In these trials, mean changes in the AIMS total score were significantly greater with valbenazine 80 mg than with placebo. Currently, no minimal clinically important difference (MCID) has been established for the AIMS total score in patients with TD. Using valbenazine trial data, analyses were conducted to establish a MCID for AIMS total score in TD.
Data were pooled from three 6-week trials: KINECT (NCT01688037), KINECT 2 (NCT01733121), KINECT 3 (NCT02274558). Using the Clinical Global Impression ofChange (CGI-TD) as an anchor comparison, AIMS total score changes from baseline to Week 6 were summarized for all study participants (pooled valbenazine and placebo groups) with a “minimal” CGI-TD score of ≤3 (minimally improved or better) or “robust” ≤2 (much improved or better) at Week 6.
In the pooled population (N=373), 72% and 29% of all participants had CGI-TD scores of ≤3 and ≤2, respectively. The median (maximum, minimum) change from baseline in AIMS total score at Week 6 was -2 (-13, 8) in participants with CGI-TD score ≤3 and -3 ( 13, 8) in participants with a score ≤2.
Pooled data from 3 randomized, double-blind, placebo-controlled trials suggest that a 2 point decrease in AIMS total score may represent the minimal clinically meaningful improvement. Larger AIMS score improvements were associated with “much improved” or “very much improved” CGI TD assessments.
This study was funded by Neurocrine Biosciences, Inc.
Whether monozygotic (MZ) and dizygotic (DZ) twins differ from each other in a variety of phenotypes is important for genetic twin modeling and for inferences made from twin studies in general. We analyzed whether there were differences in individual, maternal and paternal education between MZ and DZ twins in a large pooled dataset. Information was gathered on individual education for 218,362 adult twins from 27 twin cohorts (53% females; 39% MZ twins), and on maternal and paternal education for 147,315 and 143,056 twins respectively, from 28 twin cohorts (52% females; 38% MZ twins). Together, we had information on individual or parental education from 42 twin cohorts representing 19 countries. The original education classifications were transformed to education years and analyzed using linear regression models. Overall, MZ males had 0.26 (95% CI [0.21, 0.31]) years and MZ females 0.17 (95% CI [0.12, 0.21]) years longer education than DZ twins. The zygosity difference became smaller in more recent birth cohorts for both males and females. Parental education was somewhat longer for fathers of DZ twins in cohorts born in 1990–1999 (0.16 years, 95% CI [0.08, 0.25]) and 2000 or later (0.11 years, 95% CI [0.00, 0.22]), compared with fathers of MZ twins. The results show that the years of both individual and parental education are largely similar in MZ and DZ twins. We suggest that the socio-economic differences between MZ and DZ twins are so small that inferences based upon genetic modeling of twin data are not affected.
In-spiraling supermassive black holes should emit gravitational waves, which would produce characteristic distortions in the time of arrival residuals from millisecond pulsars. Multiple national and regional consortia have constructed pulsar timing arrays by precise timing of different sets of millisecond pulsars. An essential aspect of precision timing is the transfer of the times of arrival to a (quasi-)inertial frame, conventionally the solar system barycenter. The barycenter is determined from the knowledge of the planetary masses and orbits, which has been refined over the past 50 years by multiple spacecraft. Within the North American Nanohertz Observatory for Gravitational Waves (NANOGrav), uncertainties on the solar system barycenter are emerging as an important element of the NANOGrav noise budget. We describe what is known about the solar system barycenter, touch upon how uncertainties in it affect gravitational wave studies with pulsar timing arrays, and consider future trends in spacecraft navigation.
Successful treatment of pediatric disorders has necessitated the development of alternative medication formulations, as children may prefer alternative dosage forms to tablets or capsules. This is especially true for attention-deficit/hyperactivity disorder (ADHD), which is one of the most common chronic pediatric conditions and often involves children with a variety of overlapping physical, psychological, or neurodevelopmental disorders. A special challenge for developing alternative dosage forms for ADHD treatment is the incorporation of a once-daily long-acting formulation. Traditional ADHD medication formulations have been limited, and issues surrounding prescribed dosing regimens—including poor medication adherence, difficulty swallowing, and the lack of dosing titration options—persist in ADHD treatment. In other disease areas, the development of alternative formulations has provided options for patients who have issues with consuming solid dosage forms, particularly children and individuals with developmental disorders. In the light of these new developments, several alternative formulations for ADHD medications are under development or have recently become available. This article reviews the various strategies for developing alternative dosage forms in other disease areas and discusses the application of these strategies in ADHD treatment. Alternative dosage forms may increase medication adherence, compliance, and patient preference and, therefore, improve the overall treatment for ADHD.
Aripiprazole lauroxil (AL) is a long-acting injectable atypical antipsychotic that was evaluated for the treatment of schizophrenia in a randomized, placebo-controlled, Phase 3 study. Here, we present exploratory analyses of supportive efficacy endpoints.
Patients experiencing an acute exacerbation of schizophrenia received AL 441 mg intramuscularly (IM), AL 882 mg IM, or matching placebo IM monthly. Supportive endpoints included changes from baseline at subsequent time points in Clinical Global Impression-Severity (CGI-S) scale score; Positive and Negative Syndrome Scale (PANSS) Total score; PANSS Positive, Negative, and General Psychopathology subscale scores; PANSS Marder factors (post hoc); and PANSS responder rate. Overall response rate, based on PANSS Total score and Clinical Global Impression–Improvement (CGI-I) scale score, was also analyzed.
Of 622 patients who were randomized, 596 had ≥1 post-baseline PANSS score. Patients were markedly ill at baseline (mean PANSS Total scores 92–94). Compared with placebo, CGI-S scores; PANSS Positive, Negative, and General Psychopathology subscale scores; and PANSS Marder factors were all significantly (p<0.001) improved by Day 85 with both AL doses, with significantly lower scores starting from Day 8 in most instances. Treatment response rates were significantly (p<0.001) greater with both doses of AL vs placebo.
AL demonstrated robust efficacy on CGI-S score, PANSS subscale scores, PANSS Marder factors, and response rates. Study limitations included use of a fixed dose for initial oral aripiprazole and fixed monthly AL doses without the option to individualize the oral initiation dosing or injection frequency for efficacy, tolerability, or safety.
Cariprazine, a dopamine D3/D2 partial agonist atypical antipsychotic with preferential binding to D3 receptors, is approved for the treatment of schizophrenia and manic or mixed episodes associated with bipolar I disorder. The efficacy and safety of cariprazine was established in three randomized, double-blind, placebo-controlled, 6-week trials in patients with acute exacerbation of schizophrenia. This 53-week study evaluated the long-term safety and tolerability of cariprazine in patients with schizophrenia.
This was a multicenter, open-label, flexible-dose study of cariprazine 3–9 mg/d in adults with schizophrenia. Participants included new patients and patients who had completed one of two phase III lead-in studies (NCT01104766, NCT01104779). Eligible patients entered a no-drug screening period of up to 1 week followed by 48 weeks of flexibly dosed, open-label cariprazine treatment (3–9 mg/d) and 4 weeks of safety follow-up.
A total of 586 patients received open-label cariprazine treatment, ~39% of whom completed the study. No unexpected safety issues or deaths were reported. The most common (≥10%) adverse events (AEs) observed were akathisia (16%), headache (13%), insomnia (13%), and weight gain (10%). Serious AEs occurred in 59 (10.1%) patients, and 73 (12.5%) patients discontinued the study due to AEs during open-label treatment. Mean changes in metabolic, hepatic, and cardiovascular parameters were not considered clinically relevant. Mean body weight increased by 1.5 kg during the study, prolactin levels decreased slightly, and measures of efficacy remained stable.
Long-term cariprazine treatment at doses up to 9 mg/d appeared to be generally safe and well tolerated in patients with schizophrenia.
Salmonella is a leading cause of bacterial foodborne illness. We report the collaborative investigative efforts of US and Canadian public health officials during the 2013–2014 international outbreak of multiple Salmonella serotype infections linked to sprouted chia seed powder. The investigation included open-ended interviews of ill persons, traceback, product testing, facility inspections, and trace forward. Ninety-four persons infected with outbreak strains from 16 states and four provinces were identified; 21% were hospitalized and none died. Fifty-four (96%) of 56 persons who consumed chia seed powder, reported 13 different brands that traced back to a single Canadian firm, distributed by four US and eight Canadian companies. Laboratory testing yielded outbreak strains from leftover and intact product. Contaminated product was recalled. Although chia seed powder is a novel outbreak vehicle, sprouted seeds are recognized as an important cause of foodborne illness; firms should follow available guidance to reduce the risk of bacterial contamination during sprouting.
New radiocarbon calibration curves, IntCal04 and Marine04, have been constructed and internationally ratified to replace the terrestrial and marine components of IntCal98. The new calibration data sets extend an additional 2000 yr, from 0–26 cal kyr BP (Before Present, 0 cal BP = AD 1950), and provide much higher resolution, greater precision, and more detailed structure than IntCal98. For the Marine04 curve, dendrochronologically-dated tree-ring samples, converted with a box diffusion model to marine mixed-layer ages, cover the period from 0–10.5 cal kyr BP. Beyond 10.5 cal kyr BP, high-resolution marine data become available from foraminifera in varved sediments and U/Th-dated corals. The marine records are corrected with site-specific 14C reservoir age information to provide a single global marine mixed-layer calibration from 10.5–26.0 cal kyr BP. A substantial enhancement relative to IntCal98 is the introduction of a random walk model, which takes into account the uncertainty in both the calendar age and the 14C age to calculate the underlying calibration curve (Buck and Blackwell, this issue). The marine data sets and calibration curve for marine samples from the surface mixed layer (Marine04) are discussed here. The tree-ring data sets, sources of uncertainty, and regional offsets are presented in detail in a companion paper by Reimer et al. (this issue).
We calibrated portions of the radiocarbon time scale with combined 230Th, 231Pa, 14C measurements of corals collected from Espiritu Santo, Vanuatu and the Huon Peninsula, Papua New Guinea. The new data map 14C variations ranging from the current limit of the tree-ring calibration [11,900 calendar years before present (cal BP), Kromer and Spurk 1998, now updated to 12,400 cal B P, see Kromer et al., this issue], to the 14C-dating limit of 50,000 cal BP, with detailed structure between 14 to 16 cal kyr BP and 19 to 24 cal kyr BP. Samples older than 25,000 cal BP were analyzed with high-precision 231Pa dating methods (Pickett et al. 1994; Edwards et al. 1997) as a rigorous second check on the accuracy of the 230Th ages. These are the first coral calibration data to receive this additional check, adding confidence to the age data forming the older portion of the calibration. Our results, in general, show that the offset between calibrated and 14C ages generally increases with age until about 28,000 cal BP, when the recorded 14C age is nearly 6800 yr too young. The gap between ages before this time is less; at 50,000 cal BP, the recorded 14C age is 4600 yr too young. Two major 14C-age plateaus result from a 130 drop in Δ14C between 14–15 cal kyr BP and a 700 drop in Δ14C between 22–25 cal kyr BP. In addition, a large atmospheric Δ14C excursion to values over 1000 occurs at 28 cal kyr BP. Between 20 and 10 cal kyr BP, a component of atmospheric Δ14C anti-correlates with Greenland ice δ18O, indicating that some portion of the variability in atmospheric Δ14C is related to climate change, most likely through climate-related changes in the carbon cycle. Furthermore, the 28-kyr excursion occurs at about the time of significant climate shifts. Taken as a whole, our data indicate that in addition to a terrestrial magnetic field, factors related to climate change have affected the history of atmospheric 14C.
We analyzed birth order differences in means and variances of height and body mass index (BMI) in monozygotic (MZ) and dizygotic (DZ) twins from infancy to old age. The data were derived from the international CODATwins database. The total number of height and BMI measures from 0.5 to 79.5 years of age was 397,466. As expected, first-born twins had greater birth weight than second-born twins. With respect to height, first-born twins were slightly taller than second-born twins in childhood. After adjusting the results for birth weight, the birth order differences decreased and were no longer statistically significant. First-born twins had greater BMI than the second-born twins over childhood and adolescence. After adjusting the results for birth weight, birth order was still associated with BMI until 12 years of age. No interaction effect between birth order and zygosity was found. Only limited evidence was found that birth order influenced variances of height or BMI. The results were similar among boys and girls and also in MZ and DZ twins. Overall, the differences in height and BMI between first- and second-born twins were modest even in early childhood, while adjustment for birth weight reduced the birth order differences but did not remove them for BMI.
Dextromethorphan (DM)/quinidine (Q) is an approved treatment for pseudobulbar affect (PBA) based on trials in amyotrophic lateral sclerosis or multiple sclerosis. PRISM II evaluated DM/Q effectiveness and tolerability for PBA secondary to dementia, stroke, or traumatic brain injury; dementia cohort results are reported.
This was an open-label, multicenter, 90 day trial; patients received DM/Q 20/10 mg twice daily. Primary outcome was change in Center for Neurologic Study–Lability Scale (CNS-LS) score. Secondary outcomes included PBA episode count and Clinical and Patient/Caregiver Global Impression of Change scores with respect to PBA (CGI-C/PGI-C).
134 patients were treated. CNS-LS improved by a mean (SD) of 7.2 (6.0) points at Day 90/Endpoint (P<.001) vs. baseline. PBA episodes were reduced 67.7% (P<.001) vs. baseline; global measures showed 77.5% CGI-C and 76.5% PGI-C “much”/”very much” improved. Adverse events included headache (7.5%), urinary tract infection (4.5%), and diarrhea (3.7%); few patients dropped out for adverse events (10.4%).
DM/Q significantly reduced PBA symptoms in patients with dementia; reported adverse events were consistent with the known safety profile of DM/Q.
A trend toward greater body size in dizygotic (DZ) than in monozygotic (MZ) twins has been suggested by some but not all studies, and this difference may also vary by age. We analyzed zygosity differences in mean values and variances of height and body mass index (BMI) among male and female twins from infancy to old age. Data were derived from an international database of 54 twin cohorts participating in the COllaborative project of Development of Anthropometrical measures in Twins (CODATwins), and included 842,951 height and BMI measurements from twins aged 1 to 102 years. The results showed that DZ twins were consistently taller than MZ twins, with differences of up to 2.0 cm in childhood and adolescence and up to 0.9 cm in adulthood. Similarly, a greater mean BMI of up to 0.3 kg/m2 in childhood and adolescence and up to 0.2 kg/m2 in adulthood was observed in DZ twins, although the pattern was less consistent. DZ twins presented up to 1.7% greater height and 1.9% greater BMI than MZ twins; these percentage differences were largest in middle and late childhood and decreased with age in both sexes. The variance of height was similar in MZ and DZ twins at most ages. In contrast, the variance of BMI was significantly higher in DZ than in MZ twins, particularly in childhood. In conclusion, DZ twins were generally taller and had greater BMI than MZ twins, but the differences decreased with age in both sexes.
For over 100 years, the genetics of human anthropometric traits has attracted scientific interest. In particular, height and body mass index (BMI, calculated as kg/m2) have been under intensive genetic research. However, it is still largely unknown whether and how heritability estimates vary between human populations. Opportunities to address this question have increased recently because of the establishment of many new twin cohorts and the increasing accumulation of data in established twin cohorts. We started a new research project to analyze systematically (1) the variation of heritability estimates of height, BMI and their trajectories over the life course between birth cohorts, ethnicities and countries, and (2) to study the effects of birth-related factors, education and smoking on these anthropometric traits and whether these effects vary between twin cohorts. We identified 67 twin projects, including both monozygotic (MZ) and dizygotic (DZ) twins, using various sources. We asked for individual level data on height and weight including repeated measurements, birth related traits, background variables, education and smoking. By the end of 2014, 48 projects participated. Together, we have 893,458 height and weight measures (52% females) from 434,723 twin individuals, including 201,192 complete twin pairs (40% monozygotic, 40% same-sex dizygotic and 20% opposite-sex dizygotic) representing 22 countries. This project demonstrates that large-scale international twin studies are feasible and can promote the use of existing data for novel research purposes.