Large scale association analysis identifies three susceptibility loci for coronary artery disease.

Genome wide association studies (GWAS) and their replications that have associated DNA variants with myocardial infarction (MI) and/or coronary artery disease (CAD) are predominantly based on populations of European or Eastern Asian descent. Replication of the most significantly associated polymorphisms in multiple populations with distinctive genetic backgrounds and lifestyles is crucial to the understanding of the pathophysiology of a multifactorial disease like CAD. We have used our Lebanese cohort to perform a replication study of nine previously identified CAD/MI susceptibility loci (LTA, CDKN2A-CDKN2B, CELSR2-PSRC1-SORT1, CXCL12, MTHFD1L, WDR12, PCSK9, SH2B3, and SLC22A3), and 88 genes in related phenotypes. The study was conducted on 2,002 patients with detailed demographic, clinical characteristics, and cardiac catheterization results. One marker, rs6922269, in MTHFD1L was significantly protective against MI (OR=0.68, p=0.0035), while the variant rs4977574 in CDKN2A-CDKN2B was significantly associated with MI (OR=1.33, p=0.0086). Associations were detected after adjustment for family history of CAD, gender, hypertension, hyperlipidemia, diabetes, and smoking. The parallel study of 88 previously published genes in related phenotypes encompassed 20,225 markers, three quarters of which with imputed genotypes The study was based on our genome-wide genotype data set, with imputation across the whole genome to HapMap II release 22 using HapMap CEU population as a reference. Analysis was conducted on both the genotyped and imputed variants in the 88 regions covering selected genes. This approach replicated HNRNPA3P1-CXCL12 association with CAD and identified new significant associations of CDKAL1, ST6GAL1, and PTPRD with CAD. Our study provides evidence for the importance of the multifactorial aspect of CAD/MI and describes genes predisposing to their etiology.

The role of anxious and hyperthymic temperaments in mental disorders: a national epidemiologic study.

Temperament has been demonstrated clinically to be linked to mental disorders. We aimed to determine the possible role of temperament in mental disorders in a national epidemiologic study. A nationally representative sample of adults (n=1320) was administered the Lebanese-Arabic version of the Temperament Evaluation of the Memphis, Pisa, Paris and San Diego Autoquestionnaire (TEMPS-A), and the Arabic CIDI 3.0, as part of the LEBANON study. The association among temperaments and DSM-IV mood, anxiety, and impulse control disorders was assessed. The anxious temperament was shown to be a robust predictor of most disorders, especially within the anxiety and depressive clusters. The hyperthymic temperament had a uniquely protective effect on most mental disorders, with the exception of separation anxiety, bipolar, substance abuse and impulse control disorders. These effects were moderated by age and education. Temperaments, previously largely neglected in epidemiologic studies, could play a major role in the origin of mental disorders.

The I allele of the angiotensin converting enzyme I/D polymorphism confers protection against coronary artery disease.

BACKGROUND: Mutations in genes regulating lipid metabolism, vasoactivity, and coagulation are important modulators of coronary artery disease (CAD). OBJECTIVE: This study investigated the association between allelic variants of the angiotensin converting enzyme (ACE), methytetrahydrofolate reductase, plasminogen activator inhibitor-1 and factor V genes and CAD. METHODS: Clinical, biochemical, and angiographic information were collected from 300 patients who underwent cardiac catheterization and their DNA was genotyped by restriction fragment length polymorphism. RESULTS: The frequency of the D allele of the ACE gene was significantly higher than the I allele in patients with more than 70% stenosis in any vessel. Among patients with more than 70% stenosis, carriers of the D allele were 2.8 times more likely to be males. The presence of the ACE I allele was negatively associated with CAD with (P=0.02 ,OR=0.38.) CONCLUSION: This study describes a protective role of the ACE I allele in individuals who may be at risk of developing CAD.

Neighbourhood influences on narghile smoking among youth in Beirut.

BACKGROUND: Increasingly neighbourhoods are identified as influencing health. Neighbourhood characteristics have been linked to cigarette use. In Lebanon, the water pipe (narghile) use is most frequent among youth. The current study is aimed at identifying differential neighbourhood influences on smoking narghile among youth. METHODS: A quantitative interview was completed with 1294 adolescents, 13-20 years, in three urban disadvantaged neighbourhoods of Beirut. Individual and social factors, suggested by the literature, were associated with smoking narghile. The neighbourhood variation in the influence of these factors was then explored. Bivariate and stratified logistic regression analysis were conducted, neighbourhood being the stratification variable. RESULTS: About 60% of respondents had ever tried a narghile, about one-fifth continued to smoke. Several individual-level and social variables predicted narghile smoking bivariately. The influences on narghile smoking varied by neighbourhood. Neighbourhood differences persisted at the multivariate level. Consistently across neighbourhoods, the influence of friends was the predominant predictor of narghile smoking. In one neighbourhood, maternal smoking was a risk factor for narghile smoking of youth, in another paternal smoking. Being female seems to be protective in two of the three neighbourhoods. Other factors also differentially influence narghile use by neighbourhood. CONCLUSIONS: The mechanisms of influence of neighbourhoods on health are not clearly understood, but a transactional paradigm seems most fitting with the results found in this research. Interventions to prevent the narghile smoking should address multiple levels of influence; and must be tailored to the particular aspects of neighbourhoods which are influential in the uptake of this behaviour.

'It won't happen to me': the knowledge-attitude nexus in adolescent smoking.

BACKGROUND: Behavioral models state that adolescents need not only to know about the dangers of smoking, but also to perceive themselves as susceptible to those dangers prior to modifying their smoking behavior. However, this hypothesis has not been tested in developing world settings where the context of tobacco use may differ. METHODS: Survey data were collected from a sample of 1294 adolescents 13-20 years of age--from three under-privileged suburbs of Beirut, Lebanon. Scores were calculated to measure the knowledge of and the perceived susceptibility by a series of statements related to the consequences of tobacco use. Bivariate and multivariate methods were used to assess the association of knowledge and perceived susceptibility with smoking, controlling for socio-demographic variables. RESULTS: A logistic regression model showed that the odds of ever smoking among adolescents who had less knowledge of smoking were 1.9 times those of adolescents with more knowledge. Similar odds were demonstrated for adolescents who did not perceive themselves susceptible to smoking hazards compared with those who did. CONCLUSIONS: These results suggest that awareness campaigns should focus on raising the perceived susceptibility of adolescents by including items that are more within the realm of an adolescent's frame of mind such as smelly clothes and discolored teeth.

Harboring illnesses: on the association between disease and living conditions in a Palestinian refugee camp in Lebanon.

This research examined the association between the domestic built environment in a Palestinian refugee camp in Beirut, Lebanon, and the presence of illness among household members. Data on the domestic built environment, socio-demographics and health were collected in 860 households. The association between the presence of illness among household members and three environmental indices, namely infrastructure and services, housing conditions, and crowding was evaluated. These indices were based on a number of items that reflected the existing problems in the domestic built environment. The main finding was the positive association between poor housing conditions and the presence of illness among household members. Households with 8 - 15 housing problems were twice more likely to report the presence of illness than those with less than four housing problems (OR=2.08, 95% CI=1.40 - 3.11). This research contributes to the understanding of the influence of the built environment on the health of a refugee population.

Paid Work and Domestic Labor in Disadvantaged Communities on the Outskirts of Beirut, Lebanon.

This article explored the association between economic activity and the contribution to domestic labor in a Middle Eastern society. Analyses were carried out on cross-sectional survey data from 5,998 individuals, aged between 18 and 64 years, in three poor communities in the suburbs of Beirut, Lebanon. Domestic labor was evaluated with a composite index that takes into account both the type of task performed and the level of involvement. Housework categories included core household chores, care giving, financial management, home management, and home/car maintenance. Results showed that women continue to do most of the domestic labor in the three communities. However, women's load of domestic labor decreased as they joined the labor market, whereas men's contribution to domestic labor increased with involvement in paid work. Relatively speaking, the difference in contribution to housework between house members engaged and not engaged in paid labor was much higher for women than it was for men.

Prevalence of reproductive tract infections, genital prolapse, and obesity in a rural community in Lebanon.

OBJECTIVE: To determine the prevalence of reproduction-related illnesses in a rural community in Lebanon. METHODS: Data were collected through interviews with women in their homes, physical examinations and history taking by physicians in a clinic in the community, and laboratory tests. A total of 557 ever-married women aged 15-60 years were selected randomly. FINDINGS: Just over half of the sample (268, 50.6%) had five or more children, and (320, 78.9%) of women aged < 45 years were using contraception. The prevalence of reproductive tract infections was very low: six (1.2%) women had sexually transmitted diseases and 47 (9.3%) had endogenous reproductive tract infections. None had chlamydial infection or a positive serological finding of syphilis. None had invasive cervical cancer, and only one had cervical dysplasia. In contrast, genital prolapse and gynaecological morbidity were elevated. Half of the women studied (251, 49.6%) had genital prolapse, and 153 (30.2%) were obese. CONCLUSION: The prevalence of reproductive tract infections in this conservative rural community in east Lebanon was low. Possible explanations include the conservative nature of the community, the high rate of utilization of health care services, and the liberal use of antibiotics without a prescription. More importantly, the study showed an unexpectedly high prevalence of genital prolapse and obesity--a finding that has clear implications for primary health care priorities in such rural communities.