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PubMed2007

Sagittal balance of the pelvis-spine complex and lumbar degenerative diseases. A comparative study about 85 cases.

Retrospective analysis of the spino-pelvic alignment in a population of 85 patients with a lumbar degenerative disease. Several previous publications reported the analysis of spino-pelvic alignment in the normal and low back pain population. Data suggested that patients with lumbar diseases have variations of sagittal alignment such as less distal lordosis, more proximal lumbar lordosis and a more vertical sacrum. Nevertheless most of these variations have been reported without reference to the pelvis shape which is well-known to strongly influence spino-pelvic alignment. The objective of this study was to analyse spino-pelvic parameters, including pelvis shape, in a population of 85 patients with a lumbar degenerative disease and compare these patients with a control group of normal volunteers. We analysed three different lumbar degenerative diseases: disc herniation (DH), n = 25; degenerative disc disease (DDD), n = 32; degenerative spondylolisthesis (DSPL), n = 28. Spino-pelvic alignment was analysed pre-operatively on full spine radiographs. Spino-pelvic parameters were measured as following: pelvic incidence, sacral slope, pelvic tilt, lumbar lordosis, thoracic kyphosis, spino-sacral angle and positioning of C7 plumb line. For each group of patients the sagittal profile was compared with a control population of 154 asymptomatic adults that was the subject of a previous study. In order to understand variations of spino-pelvic parameters in the patients' population a stratification (matching) according to the pelvic incidence was done between the control group and each group of patients. Concerning first the pelvis shape, patients with DH and those with DDD demonstrated to have a mean pelvic incidence equal to 49.8 degrees and 51.6 degrees, respectively, versus 52 degrees for the control group (no significant difference). Only young patients, less than 45 years old, with a disc disease (DH or DDD) demonstrated to have a pelvic incidence significantly lower (48.3 degrees) than the control group, P < 0.05. On the contrary, in the DSPL group the pelvic incidence was significantly greater (60 degrees) than the control group (52 degrees), P < 0.0005. Secondly the three groups of patients were characterized by significant variations in spino-pelvic alignment: anterior translation of the C7 plumb line (P < 0.005 for DH, P < 0.05 for DDD and P < 0.05 for DSPL); loss of lumbar lordosis after matching according to pelvic incidence (P < 0.0005 for DH, DDD and DSPL); decrease of sacral slope after matching according to pelvic incidence (P = 0.001 for DH, P < 0.0005 for DDD and P < 0.0005 for DSPL). Measurement of the pelvic incidence and matching according to this parameter between each group of patients and the control group permitted to understand variations of spino-pelvic parameters in a population of patients.

Adult↗

PubMed2006

Age stratified, perioperative, and one-year mortality after abdominal aortic aneurysm repair: a statewide experience.

OBJECTIVE: The purpose of this study was to determine the in-hospital, 30-day, and 365-day mortality for the open repair of abdominal aortic aneurysms (AAAs), when stratified by age, in the general population. Age stratification could provide clinicians with information more applicable to an individual patient than overall mortality figures. METHODS: In a retrospective analysis, data were obtained from the California Office of Statewide Health Planning and Development (OSHPD) for the years 1995 to 1999. Out-of-hospital mortality was determined via linkage to the state death registry. All patients undergoing AAA repair as coded by International Classification of Diseases, 9th Revision (ICD-9) procedure code 38.44 and diagnosis codes 441.4 (intact) and 441.3/441.5 (ruptured) in California were identified. Patients <50 years of age were excluded. We determined in-hospital, 30-day, and 365-day mortality, and stratified our findings by patient age. Multivariate logistic regression was used to determine predictors of mortality in the intact and ruptured AAA cohorts. RESULTS: We identified 12,406 patients (9,778 intact, 2,628 ruptured). Mean patient age was 72.4 +/- 7.2 years (intact) and 73.9 +/- 8.2 (ruptured). Men comprised 80.9% of patients, and 90.8% of patients were white. Overall, intact AAA patient mortality was 3.8% in-hospital, 4% at 30 days, and 8.5% at 365 days. There was a steep increase in mortality with increasing age, such that 365-day mortality increased from 2.9% for patients 51 to 60 years old to 15% for patients 81 to 90 years old. Mortality from day 31 to 365 was greater than both in-hospital and 30-day mortality for all but the youngest intact AAA patients. Perioperative (in-hospital and 30-day) mortality for ruptured cases was 45%, and mortality at 1 year was 54%. CONCLUSIONS: There is continued mortality after the open repair of AAAs during postoperative days 31 to 365 that, for many patients, is greater than the perioperative death rate. This mortality increases dramatically with age for both intact and ruptured AAA repair.

Age Distribution↗

PubMed2002

The Human Genome Project and the future of diagnostics, treatment and prevention.

The Human Genome Project, the mapping of our 30,000-50,000 genes and the sequencing of all of our DNA, will have major impact on biomedical research and the whole of therapeutic and preventive health care. The tracing of genetic diseases to their molecular causes is rapidly expanding diagnostic and preventive options. The increased insights into molecular pathways, gained from high-throughput 'functional genomics', using DNA-chip and protein-chip approaches and specially designed animal model systems, will open great prospects for pharmacological and genetic therapies. Powerful bioinformatics and biostatistics will further improve our pattern recognition and accelerate progress. A rapidly expanding area of high expectations is that of 'pharmacogenomics': the design of more effective drugs with lower toxicity through tailoring of drug treatment to individual, genetically determined differences in drug metabolism. Not only will this decrease the cost of health care through reduction of adverse drug reactions, but a better stratification of populations will also provide more statistical power farther upstream in drug trials. However, the optimal benefits from the current explosion of 'data mining' will only be realized when the basic data are made and kept publicly accessible, while at the same time safeguarding the protection of intellectual property arising from downstream inventions. This is one of the goals of HUGO, the international Human Genome Organization, established 13 years ago to assist coordination of data acquisition and exchange and societal implementation of the genome project. Additional points of attention in this historic endeavour are the prevention of stigmatization and discrimination and the safeguarding of a worldwide balance in the contribution by--and benefits to--different populations, while respecting the diversity in cultures and traditions.

Ethics, Medical↗

PubMed1999

Higher relative, but lower absolute risks of myocardial infarction in women than in men: analysis of some major risk factors in the SHEEP study. The SHEEP Study Group.

OBJECTIVES: Middle-aged men have often been the subjects of multifactorial studies of myocardial infarction (MI) risk factors. One major objective of the SHEEP study was to compare the effects of different MI risk factors in women and men. DESIGN: SHEEP (Stockholm Heart Epidemiology Program) is a population-based case-referent study of causes of MI (first event) in Swedish women and men aged 45-70 years. During the period 1992-94, 2246 cases of MI were identified; 34% of the cases were women and 27% of the cases were fatal. One referent per case was chosen randomly from the Stockholm County population after stratification for the case's sex and age. Logistic regression was used to estimate the relative risks associated with risk factors of primary interest (diabetes, hypercholesterolaemia, hypertriglyceridaemia, hypertension, overweight, physical inactivity, smoking and job strain). RESULTS: The relative risk estimates ranged from 1.5 to 4.4 in women and from 1.3 to 2.9 in men (results for nonfatal cases and their referents). None of the 95% confidence intervals included 1.0. The relative risks were higher in the women than in the men (101-180%). The absolute risks, however, were all lower in the women than in the men. Estimates of Rothman's synergy index for gender ranged from 1.0 (hypertension) to 1.8 (current smoking). CONCLUSIONS: The indications of some effect modification due to sex (stronger risks in men for certain exposures) invoke the question of possible mechanisms.

Aged↗

PubMed1996

Assessment of the safety and efficacy of the monoclonal anti-tumor necrosis factor antibody-fragment, MAK 195F, in patients with sepsis and septic shock: a multicenter, randomized, placebo-controlled, dose-ranging study.

OBJECTIVE: To investigate the safety, biological effects, and efficacy of the anti-tumor necrosis factor (TNF) antibody fragment, MAK 195F, in a phase II trial in patient with severe sepsis. DESIGN: Prospective, randomized, open label, placebo-controlled, dose-ranging, multicenter, multinational clinical trial. SETTING: Sixteen academic medical centers' intensive care units in six European countries. PATIENTS: One hundred twenty-two patients with severe sepsis or septic shock who received standard supportive care and antimicrobial therapy. INTERVENTIONS: Patients received one of three different doses of the anti-TNF antibody (0.1 mg/kg, 0.3 mg/kg, or 1.0 mg/kg) or placebo; the antibody or placebo was given in nine doses at 8-hr intervals over 3 days. MEASUREMENTS AND MAIN RESULTS: There were no significant differences in mortality rates among the groups receiving various doses of the anti-TNF antibody or placebo, but patients with baseline serum interleukin (IL)-6 concentrations of > 1000 pg/mL appeared to benefit from MAK 195F in a dose-dependent fashion. Increased circulating IL-6 concentrations, but not TNF concentrations, were found to be important prognostic indicators for mortality for the patients in the placebo and the two lower dosage groups but not in the high dosage group (1 mg/kg). IL-6 concentrations decreased during the first 24 hrs of treatment in all three anti-TNF groups but not in the placebo group. MAK 195F was well tolerated by all patients. Human antimurine antibodies developed in 40% of the patients receiving the antibody. CONCLUSIONS: There was no increase in survival from sepsis for the patients receiving anti-TNF treatment in the overall study population. Retrospective stratification of patients by IL-6 concentrations suggests beneficial effects of the drug for patients with baseline circulating IL-6 concentrations of > 1000 pg/mL. This hypothesis requires validation in a larger, blinded, prospective study.

Antibodies, Monoclonal↗

PubMed2005

Predicting vascular risk in Type 1 diabetes: stratification in a hospital based population in Scotland.

AIMS: To estimate the absolute cardiovascular risk of patients with Type 1 diabetes attending hospital diabetes clinics in Scotland and to develop a method for identifying those at highest risk, thus enabling therapy to be targeted. METHODS: Baseline information was collected for 2136 patients with Type 1 diabetes using the Royal College of Physicians of Edinburgh Diabetes Register. These records were then linked to diagnoses of macrovascular disease in databases of the Information Statistics Division of the Common Services Agency. RESULTS: During six to nine years of follow up 110 patients (5%) developed macrovascular disease. There were significant associations between baseline age (P < 0.00001), blood pressure (P < 0.00001), albuminuria (P < 0.0002), HbA1c (P < 0.001), cholesterol (P < 0.00001) and smoking status (P < 0.00001) with the development of macrovascular disease. A scoring system for future macrovascular risk was developed from a multivariate analysis of this data. CONCLUSIONS: The data confirm the high vascular risk of patients with Type 1 diabetes. The relationship with age is such that those patients above 50 years require only one additional risk factor to reach such a high vascular risk that intervention is indicated. Using these data many patients between the age of 40 and 49 years are also likely to be identified to be at high risk.

Adult↗

PubMed2006

Detection of parent-of-origin effects in nuclear families using haplotype analysis.

Despite the potential pitfalls of stratification, population-based association studies nowadays are being conducted more often than family-based association studies. However, the mechanism of genomic imprinting has lately been implicated in the etiology of genetic complex diseases and can be detected using statistics only in family-based designs. Powerful tests for association and imprinting have been proposed previously for case-parent trios and single markers. Since the power of association studies can be improved if multiple affected children and haplotypes are considered, we extended the parental asymmetry test (PAT) for imprinting to a test that is suited for both general nuclear families and haplotypes, called HAP-PAT. Significance of the HAP-PAT is determined via a Monte-Carlo simulation procedure. In addition to the HAP-PAT, we modified a haplotype-based association test, proposed by us before, in such a way that either only paternal or maternal transmissions contribute to the test statistic. The approaches were implemented in FAMHAP and we evaluated their performance under a variety of disease models. We were able to demonstrate the usefulness of our haplotype-based approaches to detect parent-of-origin effects. Furthermore, we showed that also in the presence of imprinting it is more reasonable to consider all affected children of a nuclear family, than to randomly select one affected child from each family and to conduct a trio study using the selected individuals.

Computer Simulation↗

PubMed2007

NF1 plexiform neurofibroma growth rate by volumetric MRI: relationship to age and body weight.

OBJECTIVE: To longitudinally analyze changes in plexiform neurofibroma (PN) volume in relation to age and body growth in children and young adults with neurofibromatosis type 1 and inoperable, symptomatic, or progressive PNs, using a sensitive, automated method of volumetric MRI analysis. METHODS: We included patients 25 years of age and younger with PNs entered in a natural history study or in treatment trials who had volumetric MRI over > or =16 months. RESULTS: We studied 49 patients (median age 8.3 years) with 61 PNs and a median evaluation period of 34 months (range 18 to 70). The PN growth rates varied among patients, but were constant within patients. Thirty-four patients (69%) experienced > or =20% increase in PN volume during the observation period. PN volume increased more rapidly than body weight over time (p = 0.026). Younger patients had the most rapid PN growth rate. CONCLUSIONS: Volume increase of plexiform neurofibromas is a realistic and meaningful trial endpoint. In most patients plexiform neurofibroma growth rate exceeded body growth rate. The youngest patients had the fastest plexiform neurofibroma growth rate, and clinical drug development should be directed toward this population. Age stratification for clinical trials for plexiform neurofibromas should be considered.

Aging↗

PubMed1993

High-density lipoprotein cholesterol and alcohol consumption in US white and black adults: data from NHANES II.

OBJECTIVES: High-density lipoprotein (HDL) cholesterol is known to be positively related to moderate alcohol consumption from studies in selected populations. This study describes the association in a representative sample of the US adult population. METHODS: Stratification and multivariate regression analyses were used to examine HDL cholesterol levels and alcohol consumption. RESULTS: Fewer women than men reported consumption of alcohol at any frequency. Similar percentages of Whites and Blacks reported alcohol consumption. Age-adjusted mean HDL cholesterol levels were higher among alcohol drinkers than among nondrinkers in all sex-race strata. Mean HDL cholesterol levels of Whites and Blacks of both sexes increased consistently with increased frequency of consumption of beer, wine, and liquor. With age, education, body mass index, smoking, and physical activity controlled for, there were higher age-adjusted HDL cholesterol levels with increasing reported quantities of alcohol consumed. Daily or weekly use of alcohol led to an increase of 5.1 mg/dL in mean HDL cholesterol level, whereas consumption of 1 g of alcohol led to an increase of 0.87 mg/dL. CONCLUSION: Even if there is a causal association between alcohol consumption and higher HDL cholesterol levels, it is suggested that efforts to reduce coronary heart disease risks concentrate on the cessation of smoking and weight control.

Adult↗

PubMed2003

OMERACT 6 Economics Working Group report: a proposal for a reference case for economic evaluation in rheumatoid arthritis.

Standardization of methods for economic evaluation is essential for defining the methodological research agenda that will advance the discipline. Standardization also greatly facilitates the interpretation and comparison of the results of economic analyses. For these reasons, several jurisdictions now require economic evaluation, conducted according to standardized methodological guidelines, as a key ingredient in decision making for reimbursement of health treatments and technologies. The application of these general guidelines, however, can be difficult in the absence of disease-specific information. In the case of rheumatoid arthritis (RA), the recent emergence of innovative, highly effective, but also expensive treatments has created an immediate need to more fully understand the economic implications of RA treatments. With this background, the OMERACT Economics Working Group set out in 1994 to develop an RA-specific reference case for economic evaluation. This report summarizes the OMERACT process leading to specific recommendations on the 12 key elements of a proposed "reference case" for economic evaluation in RA. These elements include: study horizon, duration of therapy, extrapolation beyond trial duration, modeling beyond therapy, synthesis of comparisons where head-to-head trials do not exist, clinical outcome measures, mortality, valuation of health states, resource utilization, discontinuation of therapy, therapeutic sequence, and population risk stratification. Through these efforts, the OMERACT Economics Working Group aims to expedite and enhance the conduct and dissemination of methodological research in economic analyses in the rheumatic diseases.

Arthritis, Rheumatoid↗

PubMedDate not supplied

Organization of the inner retina following early elimination of the retinal ganglion cell population: effects on cell numbers and stratification patterns.

The present study has examined the effects of early ganglion cell elimination upon the organization of the inner retina in the ferret. The population of retinal ganglion cells was removed by optic nerve transection on the second postnatal day, and retinas were subsequently studied in adulthood. Numbers of amacrine and bipolar cells were compared in the nerve-transected and nerve-intact retinas of operated ferrets, while stratification patterns within the inner plexiform layer were compared in these and in normal ferret retinas. Early ganglion cell elimination was found to produce a 25% reduction in the population of glycine transporter-immunoreactive amacrine cells, and 18 and 15% reductions in the populations of parvalbumin and calbindin-immunoreactive amacrine cells, respectively. GABAergic amacrine cells were also reduced by 34%. The number of calbindin-immunoreactive displaced amacrine cells, by contrast, had increased in the ganglion cell-depleted retina, being three times their normal number. Other amacrine and bipolar cell types were unaffected. Despite these changes, the stratification patterns associated with these cell types remained largely intact within the inner plexiform layer. The present results demonstrate a class-specific dependency of inner retinal neurons upon the ganglion cell population in early postnatal life, but the ganglion cells do not appear to provide any critical signals for stratification within the inner plexiform layer, at least not after birth. Since they themselves do not produce stratified dendritic arbors until well after birth, the signals for stratification of the bipolar and amacrine cell processes should arise from other sources.

Amino Acid Transport Systems, Neutral↗

PubMed2006

Interest of tumor necrosis factor-alpha -308 G/A and interleukin-10 -592 C/A polymorphisms in human African trypanosomiasis.

This study aimed to determine whether single nucleotide polymorphisms (SNPs) within tumour necrosis factor-alpha (TNF) and interleukin-10 (IL10) promoters and genes are associated with human African trypanosomiasis (HAT). The polymorphisms used in the analysis were TNF(-308G/A), TNF(-238G/A), TNF(-1031T/C), TNF(+488G/A), IL10(-1082G/A) and IL10(-592C/A). A familial case-control sample of 277 individuals (102 cases and 175 parents) and a matched case-control group of 225 subjects (88 cases and 137 unrelated controls) were gathered together in this study. A conditional logistic regression was used to test for association. We carried out this analysis in the overall population and after stratification by time of exposure, age and ethnic group. Our results show that in the overall population, and after stratification by time of exposure, the IL10(-592A) allele is associated with a lower risk of disease, suggesting the possibility of a protective effect. After stratification by time of exposure, individuals homozygous for the SNP located in the TNF(-308) promoter were shown to present a higher risk of developing the disease early after exposure. Our study shows that TNF(-308G/A) and IL10(-592C/A) SNPs are polymorphisms of interest in the investigation of the genetic susceptibility to human African trypanosomiasis. Larger studies are currently underway to confirm these results.

Adult↗

PubMed1998

Calculation of roc curves in multidimensional likelihood ratio based screening with Down's syndrome as a special case.

OBJECTIVES: The development of algorithms and computer programs for the analysis of screening performance in situations with multiple normally (Gaussian) distributed selection markers and a priori risks depending on a stratification of the population. METHODS: The S-PLUS programming language was used to construct programs producing distributions of log likelihood ratios based on the Monte Carlo simulation. These distributions were used to construct programs for the calculation of roc curves, including a possible stratification of the population. RESULTS: S-PLUS programs for the analysis of screening performance are listed and described. The programs can be used without any special knowledge of S-PLUS. An example of the use of the programs is given.

Adolescent↗

PubMed1992

On inherited fertility in biological systems: a model of correlated fluctuations in the stochastic branching process.

A new evolutionary model with hereditary modes considered as correlated fluctuations of fertility has been proposed. It has been demonstrated that the model allows the global statistical properties of the system to be evaluated, e.g. the ensemble average and the probability of extinction. The results obtained show the increase of instability of a population with the enhancement of inheritance efficiency. The existence of at least an exponential stratification in the population has also been shown. Possible applications of the present model are discussed.

Animals↗

PubMed2004

A new concept for DRG-based reimbursement of services in German intensive care units: results of a pilot study.

OBJECTIVE: To evaluate LOS in developing a concept of borderline ICU LOS for a realistic reimbursement of intensive care. DESIGN: Retrospective analysis of LOS and cost data extracted from patients' electronic records. SETTING: Surgical ICU of the University Hospital Göttingen, Germany. PATIENTS AND PARTICIPANTS: All adult ICU admissions with LOS >24 h over a 24-month period (1 January 2000 to 31 December 2001; n=1631.) INTERVENTIONS: None. MEASUREMENTS AND RESULTS: Cluster analysis partitioned the ICU population into three homogeneous groups based on ICU LOS and total direct costs: cluster 1 (n=1405; mean LOS=2.8; mean cost= Euro 2399); cluster 2 (n=190; mean LOS=13.4; mean cost=Euro 12,754); cluster 3 (n=36; mean LOS=34.9; mean cost= Euro 34,173). Cost distribution between cluster 1 and clusters 2 and 3 combined was 48 vs 52%. Upper 95 percentile LOS of 6.7 allowed cluster 1 to be replaced by an LOS profile population of < or = 7 days population (n=1355; 96% population and 91% total ICU cost overlap with cluster 1) representing 83% of total ICU population and 44% of total ICU costs. Stratification of >7 day population into LOS less than or >20 days (n=220; n=56) were further differentiated by mortality (11 vs 23%) and sepsis incidence (33 vs 79%). CONCLUSIONS: It may be feasible to formulate a LOS-based reimbursement scheme for ICU services in Germany based on the selection of (appropriate) patients' ICU LOS profiles.

Cluster Analysis↗

PubMed2025

HLA-B Alleles With Shared Peptide Binding Specificities Define Global Risk of Co-trimoxazole-Induced Severe Cutaneous Adverse Drug Reactions.

BACKGROUND: Co-trimoxazole is a leading global cause of severe cutaneous adverse drug reactions (SCAR) including Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN) and drug reaction with eosinophilia and systemic symptoms (DRESS). Co-trimoxazole-induced SCAR are associated with HLA class I alleles including HLA-B∗13:01 and HLA-B∗38:02 in Southeast Asian (SEA) populations. However, the global generalizability of these associations is unknown but critical for population-appropriate risk stratification and diagnosis. OBJECTIVE: To determine HLA risk factors associated with co-trimoxazole-induced SJS/TEN and DRESS in populations from the United States and South Africa. METHODS: We performed high-resolution HLA typing on dermatologist-adjudicated co-trimoxazole-induced patients with SCAR in the United States (n = 63) and South Africa (n = 26) compared with population controls. Peptide binding and docking analyses were performed using MHCcluster2.0 and CB-Dock2. RESULTS: In a multiple logistic regression model, HLA-B∗44:03 (corrected P [Pc] < .001; odds ratio [OR] = 4.08), HLA-B∗38:01 (Pc < .001; OR = 5.66), and HLA-C∗04:01 (Pc = .003; OR = 2.50) were independently associated with co-trimoxazole-induced SJS/TEN in the United States. HLA-B∗44:03 was also associated with co-trimoxazole-induced DRESS in South Africa (Pc = .019; OR = 10.69). Distinct HLA-B variants with shared peptide binding specificities (SPBS) and HLA-C∗04:01 identified 94% and 78% of co-trimoxazole-induced SJS/TEN and DRESS in the United States, respectively. The SEA risk allele HLA-B∗13:01, with SPBS to HLA-B∗44:03, was identified in just one of 63 US patients with SCAR. CONCLUSIONS: HLA alleles with SPBS to SEA-related risk alleles, including HLA-B∗44:03 (SPBS with HLA-B∗13:01) and HLA-B∗38:01 (SPBS with HLA-B∗38:02) but also HLA-C∗04:01, predisposed to co-trimoxazole-induced SCAR in the United States and South Africa. These findings provide biological plausibility and strategies for global risk prediction and diagnosis of co-trimoxazole-induced SCAR.

Humans↗

PubMed2005

Chest pain units: management of special populations.

Chest pain units provide an important alternative to traditional hospital admission for patients who present to the emergency department with symptoms compatible with acute coronary syndrome and a normal or inconclusive initial evaluation. Although patient subgroups such as women, diabetics, those with established coronary artery disease,and those with symptoms related to stimulant use present unique challenges,management in a chest pain unit appears to be appropriate in these populations. Judicious application of accelerated diagnostic protocols and current testing methods can promote safe, accurate, and cost-effective risk stratification of special populations to identify patients who can be safely discharged and patients who require hospital admission for further evaluation.

Angina Pectoris↗

PubMed2002

Genetics of suicidal behavior: candidate association genetic approach.

Suicidal behavior runs in families and seemed to be genetically determined in part and independent of the presence of psychiatric disorders. This review presents the current knowledge of candidate gene association studies in the field of suicidology. Concordance for monozygotic twins is about 13% Vs. 0.7% in dizygotics. It seems that there is a relationship to intermediate phenotypes such as impulsivity and aggression. The problem of studying complex traits and of ethnic stratification in heterogeneous population are major concerns in studying genetics of suicide. Family-based methods is one of the strategies to overcome stratification. We found a possible association of tryptophane hydroxylase gene polymorphism with depression and serotonin transporter promoter gene to violence traits by family-based methods. Recent data from the study of COMT. MAO and serotonin receptors genes polymorphisms are controversial at this stage. Future directions for research includes alternative phenotypes, endo-phenotypes and genome scan.

Adolescent↗