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Previous research has suggested an association between depression and subsequent acute stroke incidence, but few studies have examined any effect modification by sociodemographic factors. In addition, no studies have investigated this association among primary care recipients with hypertension.
We examined the anonymized records of all public general outpatient visits by patients aged 45+ during January 2007–December 2010 in Hong Kong to extract primary care patients with hypertension for analysis. We took the last consultation date as the baseline and followed them up for 4 years (until 2011–2014) to observe any subsequent acute hospitalization due to stroke. Mixed-effects Cox models (random intercept across 74 included clinics) were implemented to examine the association between depression (ICPC diagnosis or anti-depressant prescription) at baseline and the hazard of acute stroke (ICD-9: 430–437.9). Effect modification by age, sex, and recipient status of social security assistance was examined in extended models with respective interaction terms specified.
In total, 396 858 eligible patients were included, with 9099 (2.3%) having depression, and 10 851 (2.7%) eventually hospitalized for stroke. From the adjusted analysis, baseline depression was associated with a 17% increased hazard of acute stroke hospitalization [95% confidence interval (CI) 1.03–1.32]. This association was suggested to be even stronger among men than among women (hazard ratio = 1.29, 95% CI 1.00–1.67).
Depression is more strongly associated with acute stroke incidence among male than female primary care patients with hypertension. More integrated services are warranted to address their needs.
Earlier studies examining structural brain abnormalities associated with cognitively derived subgroups were mainly cross-sectional in design and had mixed findings. Thus, we obtained cross-sectional and longitudinal data to characterize the extent and trajectory of brain structure abnormalities underlying distinct cognitive subtypes (“preserved,” “deteriorated,” and “compromised”) seen in psychotic spectrum disorders.
Data from 364 subjects (225 patients with psychotic conditions and 139 healthy controls) were first used to determine the relationship of cognitive subtypes with cross-sectional measures of subcortical volume and cortical thickness. To probe neurodevelopmental abnormalities, brain structure laterality was examined. To examine whether neuroprogressive abnormalities persist, longitudinal brain structural changes over 5 years were examined within a subset of 101 subjects. Subsequent discriminant analysis using the identified brain measures was performed on an independent subject group.
Cross-sectional comparisons showed that cortical thinning and limbic volume reductions were most widespread in “deteriorated” cognitive subtype. Laterality comparisons showed more rightward amygdala lateralization in “compromised” than “preserved” subtype. Longitudinal comparisons revealed progressive hippocampal shrinkage in “deteriorated” compared with healthy controls and “preserved” subtype, which correlated with worse negative symptoms, cognitive and psychosocial functioning. Post-hoc discrimination analysis on an independent group of 52 subjects using the identified brain structures found an overall accuracy of 71% for classification of cognitive subtypes.
These findings point toward distinct extent and trajectory of corticolimbic abnormalities associated with cognitive subtypes in psychosis, which can allow further understanding of the biological course of cognitive functioning over illness course and with treatment.
Suicide is a serious phenomenon associated with psychiatric disorders.
In the present study, we investigated factors that can predict follow-up at the psychiatric clinic after medical care at the emergency room (ER).
Medical records of the 145 patients treated at the ER following suicide attempt from Jan 1, 2009 to July 31, 2009 were reviewed. Age, sex, past psychiatric history, impulsiveness and medical severity of suicide attempt, risk-rescue rating scores, reasons for suicide attempt and methods of suicide were examined. Psychiatric diagnoses were made by psychiatrists at the initial interview with patients at ER.
The mean age of the patients was 42.9 ± 15.7 years, and 68.3 % were women and 31.7% were men. Among the suicide methods, psychotropics were the most common (69%), and ingestion of pesticides was the second (19.3%). Interpersonal problems were the most common precipitating event (57.9%), and depression was the most common (89%). About a half had previous psychiatric disorders and about one third had previous suicide attempt. Fifteen patients (10.3%) attempted planned suicide and 124 patients (85.5%) attempted impulsively. Mean risk and rescue rating scores was 8.6 ±1.6 and 12.3 ± 2.2. About one third had a follow-up psychiatric visit. The most important predictor of psychiatric follow-up was risk rating scores.
This study suggests that women with interpersonal problems and depression should be carefully monitored to reduce suicide attempt. Patients commit less risky suicide attempts tend to more loss to psychiatric follow-up, thus, need more attention to prevent suicide re-attempts.
Bupropion is a catecholamine reuptake inhibitor and also a potent noncompetitive ion channel site antagonist at the nicotinic acetylcholine receptor. Bupropion is indicated for use in combination with behavioral modification programs for smoking cessation. There have been a few studies about the effect of bupropion on smoking cessation in schizophrenia. Therefore, we aimed investigated the change of the symptomatology after smoking cessation with bupropion in the patients with schizophrenia.
There were fifty-six patients with smoking in the psychiatric ward of Hapcheon Korea Hospital. among them, thirty-nine inpatients meeting the DSM-IV criteria for schizophrenia were recruited. for 4 weeks, treatment team persuaded the patients to enter the program of smoking cessation. with the exception, if the patients did not agree the program, the patients were able to be transferred to another ward that smoking was permitted. All patients agreed to the program. Postive and Negative Symptom Scale (PANSS), Temperament and Character Inventory(TCI), State-Trait Anxiety Inventory(STAI), Fagerstrom Test for Nicotine Dependence(FTND) were evaluated at the beginning of the study and 12 weeks of Bupropion treatment.
At 12 weeks after successful smoking cessation with bupropion, FTND scores were significantly decreased after smoking cessation. the scores of STAI and PANSS were not significantly changed. the subcale of TCI, Novelty Seeking showed decreasing tendency after smoking cessation, although there was no statistical significance(p=0.054).
These results suggest that bupropion is an effective antidepressant on smoking cessation and does not aggravate the psychotic symptoms in schizophrenia. Further investigation with larger number of subjects is needed.
The prevalence of internet game use among children and adolescents has been increased in the recent years.
Internet addiction has been found to cause various psychiatric symptoms and psychological problems. Internet addiction has been found to cause various psychiatric symptoms and psychological problems.
The aim of this study was to examine the association between problematic internet game use and psychiatric symptoms in a sample of the Child and Adolescent Psychiatric Clinic, Ulsan University Hospital.
We analyzed data from 447 subjects who first visit the Child and Adolescent Psychiatric Clinic of the Ulsan University Hospital. The level of Internet addiction was categorized as either high-risk (≥108; group 3), potential risk (95 to 107; group 2), or no risk (≤94, group 1) based on the total score. Data were analyzed using SPSS version 17.0 and one-way ANOVA and multiple logistic regression method were used.
Thirteen adolescents met the criteria for high risk group of internet game addiction. in the high risk group, 10 were male and 3 were female adolescents. There was an mean difference among group 3 (high risk)< 1 (no risk),2 (potential risk) in AHI ; whereas group 3 (high risk)>1 (no risk), 2 (potential risk) in BDI, BAI, inattention, hyperactivity/impulsivity and K-ARS score. with multiple logistic regression analysis, K-scale was significantly related with male sex, BDI, ARShyperactivity/ impulsivity score.
We conclude that having male sex, happiness and depressive symptoms is associated with the risk of developing internet use disorders.
: Human impulsivity is a complex multidimensional construct encompassing cognitive, emotional, and behavioral aspects. Previous animal studies have suggested that striatal dopamine receptors play a critical role in impulsivity. in this study, we investigated the relationship between self-reported cognitive impulsiveness and dopamine D2/3 receptor availability in striatal subdivisions in healthy subjects using high-resolution positron emission tomography (PET) with [11C]raclopride.
Twenty-one participants completed 3-Tesla magnetic resonance imaging and high-resolution PET scans with [11C]raclopride. The trait of impulsiveness was measured using the Barratt Impulsiveness Scale (BIS-11). Partial correlation analysis was performed between BIS-11 scores and D2/3 receptor availability in striatal subregions, controlling for the confounding effects of temperament characteristics that are conceptually or empirically related to dopamine, which were measured by the Temperament and Character Inventory.
The analysis revealed that the non-planning (p = 0.004) and attentional (p = 0.007) impulsiveness subscale scores on the BIS-11 had significant positive correlations with D2/3 receptor availability in the pre-commissural dorsal caudate. There was a tendency toward positive correlation between non-planning impulsiveness score and D2/3 receptor availability in the post-commissural caudate.
These results suggest that cognitive subtrait of impulsivity is associated with D2/3 receptor availability in the associative striatum that plays a critical role in cognitive processes involving attention to detail, judgment of alternative outcomes, and inhibitory control.
It is known that Sexual Dysfunction (SD) is higher in patient with depression than in the general population. Though antidepressant seems to worsen the situation, there are also indications that the gender may play a role on it.
Evaluate the gender effect of sexual function among unmedicated MDD, MDD receiving antidepressant, and healthy controls.
The sample was formed by male and female Taiwanese outpatients in three age and sex matched groups, with sixty nine participants per group: unmedicated MDD, MDD receiving antidepressant, and healthy controls. the diagnoses of depressions were performed according DSM-IV and Taiwanese Depression Questionnaire. SD was evaluated with the Chinese version of the Changes in Sexual Functioning Questionnaire. Finally, the data was analyzed using SPSS software v17. Mixed designed ANOVA was used.
There are significant differences between males and females CSFQ results (sex main effect F = 82.44, p < 0.001) and between groups (group main effect F = 3.48, p = 0.034). Additionally, the 2-way interaction between sex and group was also significant (F = 3.40, p = 0.036). Simple main effect analysis shows differences among male participants, between healthy and medicated males (F = 11.41, p = 0.002), but not in female (F = 1.58, p = 0.21). However the statistics weren’t different between females groups, the medicated expresses better results (similar to healthy group) than the unmedicated one.
SD is different between genders in each of the groups. Antidepressant seems to increase SD in man, while improves sexual satisfaction/function among depressive woman. We speculate that psychological improvement after treatment may have different impact between genders on sexual satisfaction.
The presence of comorbid anxiety disorders (AD) and bipolar II disorders (BP-II) compounds disability complicates treatment, worsens prognosis, and has been understudied. The genes involved in metabolizing dopamine and encoding dopamine receptors, such as aldehyde dehydrogenase 2 (ALDH2) and dopamine D2 receptor (DRD2) genes, may be important to the pathogenesis of BP-II comorbid with AD. We aimed to clarify ALDH2 and DRD2 genes for predisposition to BP-II comorbid with and without AD. The sample consisted of 335 subjects BP-II without AD, 127 subjects BP-II with AD and 348 healthy subjects as normal control. The genotypes of the ALDH2 and DRD2 Taq-IA polymorphisms were determined using polymerase chain reactions plus restriction fragment length polymorphism analysis. Logistic regression analysis showed a statistically significant association between DRD2 Taq-I A1/A2 genotype and BP-II with AD (OR = 2.231, P = 0.021). Moreover, a significant interaction of the DRD2 Taq-I A1/A1 and the ALDH2*1*1 genotypes in BP-II without AD was revealed (OR = 5.623, P = 0.001) compared with normal control. Our findings support the hypothesis that a unique genetic distinction between BP-II with and without AD, and suggest a novel association between DRD2 Taq-I A1/A2 genotype and BP-II with AD. Our study also provides further evidence that the ALDH2 and DRD2 genes interact in BP-II, particularly BP-II without AD.
Suicide rates are high for older persons worldwide. However, no literature could be found on young-old people’s opinions about elderly suicide and the beliefs/expectations that protect them from attempting suicide.
To explore opinions about elderly suicide among community-dwelling young-old people in Taiwan and their reasons for not killing themselves.
A qualitative descriptive design was used. Young-old (65–74 years old) outpatients were recruited by convenience from two randomly selected medical centers in northern Taiwan if they had never expressed suicidal ideas and had no severe cognitive deficit. Data were collected in individual interviews and analysed by content analysis.
Among 31 participating young-old people, most participants (87.1%) had heard of elderly suicide. Their opinions about elderly suicide reflected negative emotional reactions (32.3%), judgmental attitudes (32.3%), could happen after losing the meaning of life (9.7%), and expectations of social welfare (9.7%). Reasons for not killing themselves fell into six major themes: living well (32.3%), suicide cannot resolve problems (22.6%), fear of humiliating their children (16.1%), religious beliefs (12.9%), never thought about suicide (12.9%), and living in harmony with nature (12.9%).
Among the factors that prevented participants from killing themselves, perceptions of living well and of children’s filial behavior, as well as rational thinking could be adjusted. These factors can be addressed and improved by healthcare providers and policy makers to prevent suicide among the young-old. Our findings may also serve as a reference for geriatric researchers in western countries with increasing numbers of elderly ethnic minority immigrants.
This research aimed to identify the effects of depressive mood of female high school students on dysmenorrhea and sleep quality.
This research was conducted for 2 months from September 2015 to October 2015. A total of 3 types of self-reported questionnaire were adopted for the research. Control group was separated by Zung Self-rating Depression Scale (ZSDS). Each group adopted a self-made questionnaire for research on menstruation and Pittsburgh Sleep Quality Index (PSQI) for research on sleep. Chi2 test and AVOVA analysis through SPSS-21 were used as statistics methods.
Analysis was made on 72 female students who submitted clear answers to the questionnaire. There were 34 students from normal mood group and 38 from depressive mood group. Depressive group presented meaningful results on regularity, pain severity, and drug treatment history of menstruation. Particularly, depressive group had 51.4% among subjects having severe menstrual pain of grade 3 by VMS (verbal multidimensional scoring system), way higher than 27.6% among subjects in the normal group. PSQI for sleep showed a meaningful result that 20.8% of those in the normal group were diagnosed with sleep disorder compared to 86.8% for the depressive group. A meaningful difference was seen in sleep latency, sleep duration, sleep disturbance, use of sleep medication, daytime functional disturbance among 7 items of PSQI.
This research showed that female high school students with depressive mood had high frequency and severity in dysmenorrhea and sleep quality disturbance.
Disclosure of interest
The authors have not supplied their declaration of competing interest.
In Korean culture, co-sleeping of parents and children are quite common, which is different from the Western culture where solitary sleeping of children is preferred. In this study, we evaluate the sleep environment factors that effect on children sleep disorder, and parent's parenting stress and mental health.
Surveys were conducted to 115 participating parents of preschool children sleeping behaviour lecture. Seventy-one completed surveys were analyzed for the study. The mean age of target children was 53 ± 23 months. Parents’ mental health was evaluated by using several forms such as Insomnia Severity Index, Korean-Parenting Stress Index short form, and The Patient Health Questionnaire-9. Children's sleeping environment and quality were assessed by Child Sleep Habit Questionnaire and Sleep environment survey.
Pearson correlation analysis (P < 0.05) was conducted to evaluate the relationship between the sleep disorder of children, and the parent's parenting stress and mental health. Analyzing the data through the partial least square path modeling, co-sharing would have negative effect; bed-sharing could have negative effect on the depressing emotion of parents (P = 0.065). Solitary sleeping of children could have positive effect on parent's mental health (P < 0.01).
Preschool children's sleeping disorder occurs more often in co-sleeping children with parents than solitary sleeping children. Parents’ parenting stress is related to the parent's age and depression, further related to the children sleeping disorder and their sleep environment. Although, it is difficult to generalize the exact cause, evaluation and improvement of children's sleep environment would help to reduce the parent's parenting stress.
Disclosure of interest
The authors have not supplied their declaration of competing interest.
This research examined gender variations in depressive mood for high school students affected by emotional upset and how such depressive mood affect their sleep quality.
Research was conducted from September 2015 to October 2015. Both males and females were divided into normal group and depressive group by Zung Self-rating Depression Scale (ZSDS). Each group adopted the Pittsburgh Sleep Quality Index (PSQI) to measure sleep quality.
Analysis was made on a total of 155 students, which were 83 male students and 72 female. The average ZSDS for all high school students was 43.38 and the average PSQI was 5.39. The number of male students in the normal and depressive group who were diagnosed with sleep disorder were 2 (3.8%) and 9 (29.0%), respectively (P < 0.05). But the number of female students in the normal and depressive group who were diagnosed with sleep disorder were 11 (32.4%) and 33 (86.8%), respectively (P < 0.05). Both males and females shared a meaningful result over sleep latency, sleep disturbance, use of sleep medication, and daytime functional disturbance among 7 items of PSQI for sleep quality, and female students had a significantly meaningful result over sleep duration, habitual sleep effects (P < 0.05).
This research showed that sleep quality of all high school students was not too bad but it can be problematic for those with depressive mood. Especially, female students were diagnosed with sleep disorder more than male students.
Disclosure of interest
The authors have not supplied their declaration of competing interest.
Heat shock proteins (HSPs) consist of highly preserved stress proteins that are expressed in response to stress. Two studies were carried out to investigate whether HSP genes in hair follicles from beef calves can be suggested as indicators of heat stress (HS). In study 1, hair follicles were harvested from three male Hanwoo calves (aged 172.2 ± 7.20 days) on six dates over the period of 10 April to 9 August 2017. These days provided varying temperature–humidity indices (THIs). In study 2, 16 Hanwoo male calves (aged 169.6 ± 4.60 days, with a BW of 136.9 ± 6.23 kg) were maintained (4 calves per experiment) in environmentally controlled chambers. A completely randomized design with a 2 × 4 factorial arrangement involving two periods (thermoneutral: TN; HS) and four THI treatment groups (threshold: THI = 68 to 70; mild: THI = 74 to 76; moderate THI = 81 to 83; severe: THI = 88 to 90). The calves in the different group were subjected to ambient temperature (22°C) for 7 days (TN) and subsequently to the temperature and humidity corresponding to the target THI level for 21 days (HS). Every three days (at 1400 h) during both the TN and HS periods, the heart rate (HR) and rectal temperature (RT) of each individual were measured, and hair follicles were subsequently collected from the tails of each individual. In study 1, the high variation (P < 0.0001) in THI indicated that the external environment influenced the HS to different extents. The expression levels of the HSP70 and HSP90 genes at the high-THI level were higher (P = 0.0120, P = 0.0002) than those at the low-THI level. In study 2, no differences in the THI (P = 0.2638), HR (P = 0.2181) or RT (P = 0.3846) were found among the groups during the TN period, whereas differences in these indices (P < 0.0001, P < 0.0001 and P < 0.0001, respectively) were observed during the HS period. The expression levels of the HSP70 (P = 0.0010, moderate; P = 0.0065, severe) and HSP90 (P = 0.0040, severe) genes were increased after rapid exposure to heat-stress conditions (moderate and severe levels). We conclude that HSP gene expression in hair follicles provides precise and accurate data for evaluating HS and can be considered a novel indicator of HS in Hanwoo calves maintained in both external and climatic chambers.
The influence of combined corrosion and vibration to the anti-loosening performance of a precision locknut used in a machine tool is investigated. Firstly, the locknut was submerged in 5% NaCl solution according to ASTM B895 standard for corrosion testing. The locknuts, after submerged in 1-hr, 2-hr and 4-hr periods, respectively, were then installed on the rotating spindle in a vertical dynamic impact tester for performing anti-loosening test. The initial installed pretension was 9800 N and the spindle was rotating in a constant speed of 1000 rpm. Turmogrease Li 802 EP lubricant was used on the contact surface between spindle thread and locknut. The set screws on the locknut were tightened sequentially and evenly in three-stage of torque: 1.96 N-m, 3.92 N-m and 5.88 N-m. Its real-time pretension variation with the periodic transverse impact and its final loosening torque were measured. Accordingly, the axial force ratio and anti-loosening torque ratio were calculated and discussed. It was found that corrosion treatment had similar influence on both the axial force ratio and the anti-loosening torque ratio. More corrosion on the locknut with longer submersion in NaCl solution deteriorated its anti-loosening characteristics. The result could serve as the reference for evaluating the fastening performance of precision locknut and guide the design and manufacturing for the application improvement.
To analyse how the auditory brainstem response changes in patients with sudden sensorineural hearing loss.
Data were collected via retrospective medical chart review.
Forty-three patients were included in this study. The mean latency of auditory brainstem response wave 1 was significantly longer for the affected side than for the unaffected side (p = 0.003). The mean latency of auditory brainstem response wave 1 was significantly shorter, and the mean amplitude of auditory brainstem response wave 1 was significantly larger, in the good response group compared to the poor response group. In forward conditional logistic regression analysis, auditory brainstem response wave 1 latency was an independent predictor of a good response (odds ratio = 34.37, 95 per cent confidence interval = 1.56–757.15, p = 0.025).
In patients with sudden sensorineural hearing loss, the latency of wave 1 of the auditory brainstem response was significantly increased and was related to prognosis.
We present ALMA detection of the [O iii] 88 μm line and 850 μm dust continuum emission in a Y-dropout Lyman break galaxy, MACS0416_Y1. The [O iii] detection confirms the object with a spectroscopic redshift to be z = 8.3118±0.0003. The 850 μm continuum intensity (0.14 mJy) implies a large dust mass on the order of 4×106M⊙. The ultraviolet-to-far infrared spectral energy distribution modeling, where the [O iii] emissivity model is incorporated, suggests the presence of a young (τage ≍ 4 Myr), star-forming (SFR ≍ 60M⊙yr−1), and moderately metal-polluted (Z ≍ 0.2Z⊙) stellar component with a stellar mass of 3 × 108M⊙. An analytic dust mass evolution model with a single episode of star formation does not reproduce the metallicity and dust mass in ≍ 4 Myr, suggesting an underlying evolved stellar component as the origin of the dust mass.
Abnormal effort-based decision-making represents a potential mechanism underlying motivational deficits (amotivation) in psychotic disorders. Previous research identified effort allocation impairment in chronic schizophrenia and focused mostly on physical effort modality. No study has investigated cognitive effort allocation in first-episode psychosis (FEP).
Cognitive effort allocation was examined in 40 FEP patients and 44 demographically-matched healthy controls, using Cognitive Effort-Discounting (COGED) paradigm which quantified participants’ willingness to expend cognitive effort in terms of explicit, continuous discounting of monetary rewards based on parametrically-varied cognitive demands (levels N of N-back task). Relationship between reward-discounting and amotivation was investigated. Group differences in reward-magnitude and effort-cost sensitivity, and differential associations of these sensitivity indices with amotivation were explored.
Patients displayed significantly greater reward-discounting than controls. In particular, such discounting was most pronounced in patients with high levels of amotivation even when N-back performance and reward base amount were taken into consideration. Moreover, patients exhibited reduced reward-benefit sensitivity and effort-cost sensitivity relative to controls, and that decreased sensitivity to reward-benefit but not effort-cost was correlated with diminished motivation. Reward-discounting and sensitivity indices were generally unrelated to other symptom dimensions, antipsychotic dose and cognitive deficits.
This study provides the first evidence of cognitive effort-based decision-making impairment in FEP, and indicates that decreased effort expenditure is associated with amotivation. Our findings further suggest that abnormal effort allocation and amotivation might primarily be related to blunted reward valuation. Prospective research is required to clarify the utility of effort-based measures in predicting amotivation and functional outcome in FEP.
Better understanding of interplay among symptoms, cognition and functioning in first-episode psychosis (FEP) is crucial to promoting functional recovery. Network analysis is a promising data-driven approach to elucidating complex interactions among psychopathological variables in psychosis, but has not been applied in FEP.
This study employed network analysis to examine inter-relationships among a wide array of variables encompassing psychopathology, premorbid and onset characteristics, cognition, subjective quality-of-life and psychosocial functioning in 323 adult FEP patients in Hong Kong. Graphical Least Absolute Shrinkage and Selection Operator (LASSO) combined with extended Bayesian information criterion (BIC) model selection was used for network construction. Importance of individual nodes in a generated network was quantified by centrality analyses.
Our results showed that amotivation played the most central role and had the strongest associations with other variables in the network, as indexed by node strength. Amotivation and diminished expression displayed differential relationships with other nodes, supporting the validity of two-factor negative symptom structure. Psychosocial functioning was most strongly connected with amotivation and was weakly linked to several other variables. Within cognitive domain, digit span demonstrated the highest centrality and was connected with most of the other cognitive variables. Exploratory analysis revealed no significant gender differences in network structure and global strength.
Our results suggest the pivotal role of amotivation in psychopathology network of FEP and indicate its critical association with psychosocial functioning. Further research is required to verify the clinical significance of diminished motivation on functional outcome in the early course of psychotic illness.
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.