Ziyad Mahfoud

Short- and Long-Term Safety of Weekly High-Dose Vitamin D3 Supplementation in School Children

BACKGROUND Hypovitaminosis D is prevalent in youth worldwide, but the safety of vitamin D at doses exceeding 200 IU/d is unknown in this age group. We assessed the safety of high doses of vitamin D(3) administered to apparently healthy schoolchildren. METHODS To assess short-term safety, 25 subjects randomly received placebo or vitamin D(3) at doses of 14,000 IU/wk for 8 wk. To assess long-term safety, 340 subjects randomly received placebo, vitamin D(3) as 1,400 IU/wk or 14,000 IU/wk for 1 yr. Biochemical variables were monitored at 0, 2, 4, 6, and 8 wk and 8 wk off therapy in the short-term study and at 0, 6, and 12 months in the long-term study. RESULTS In both the short- and long-term studies, mean serum calcium and 1,25-hydroxyvitamin levels did not change in any group. In the short-term study, mean 25-hydroxyvitamin concentrations increased from 44 (+/- 11) to 54 (+/- 19) ng/ml in the treated groups (P = 0.033). In the long-term study, mean 25-hydroxyvitamin D levels increased from 15 +/- 8 to 19 +/- 7 ng/ml (P < 0.0001) in subjects receiving 1,400 IU/wk and from 15 +/- 7 to 36 +/- 22 ng/ml (P < 0.0001) in the group receiving 14,000 IU/wk. No subject developed vitamin D intoxication. CONCLUSION Vitamin D(3) at doses equivalent to 2000 IU/d for 1 yr is safe in adolescents and results in desirable vitamin D levels.

Validation of the Arabic version of the Cohen perceived stress scale (PSS-10) among pregnant and postpartum women

BackgroundThis study was conducted to evaluate the validity of the Arabic translation of the Cohen Perceived Stress Scale (PSS-10) in pregnant and postpartum women.MethodsA sample of 268 women participated. These included 113 women in their third trimester of pregnancy, 97 in the postpartum period and 58 healthy female university students. GHQ-12 and EPDS were also administered to the participants. Internal consistency reliability, assessed using Cronbachs α, was 0.74.ResultsPSS-10 significantly correlated with both EPDS and GHQ12 (ρ = 0.58 and ρ = 0.48 respectively), and significantly increased with higher scores on stressful life events. PSS-10 scores were higher among university students who also recorded higher stressful life events scores.ConclusionThe Arabic translated version of the PSS-10 showed reasonably adequate psychometric properties.

HIV/AIDS among female sex workers, injecting drug users and men who have sex with men in Lebanon: results of the first biobehavioral surveys.

Objectives:To measure HIV prevalence and associated risk factors among female sex workers, injecting drug users (IDUs) and men who have sex with men (MSM) in Lebanon and the prevalence of hepatitis B virus and hepatitis C virus among IDUs. Methods and design:A cross-sectional survey of 135 female sex workers, 81 IDUs and 101 MSM was recruited using respondent-driven sampling. A structured interview was conducted by members of nongovernmental organizations working with these populations and blood was collected for serological testing. Results:HIV prevalence was 3.7% among MSM but no HIV cases were detected among female sex workers or IDUs. Among IDUs, prevalence of hepatitis C virus antibody was 51% and prevalence of hepatitis B virus surface antigen was 5%. Three-quarters of MSM had nonregular male sexual partners during the last year but only 39% reported using a condom every time. There was evidence of overlapping HIV risk: 36% of MSM and 12% of IDUs reported that they had sold sex. Previous testing for HIV was lowest among MSM (at 22%) despite their having the highest level both of knowledge about HIV and of perception of being at risk of HIV infection (67%). Conclusion:Prevention efforts at greater scale are needed to reach these at-risk populations in Lebanon. These should target MSM in particular, including access to HIV testing, but will need to address and overcome stigma. For IDUs, surveillance and prevention efforts should integrate both hepatitis C virus and HIV.

Vitamin D receptor gene polymorphisms modulate the skeletal response to vitamin D supplementation in healthy girls

OBJECTIVES Vitamin D receptor (VDR) gene plays an important role in bone mass regulation. We have previously shown a beneficial effect of vitamin D supplementation on bone mass in girls. This study investigated whether the musculo-skeletal response to Vitamin D was modulated by polymorphisms in VDR gene. DESIGN Randomized placebo-controlled trial. METHODS 179 girls (10-17 years), were randomly assigned to placebo or Vitamin D3 for one year. VDR genotypes were determined in 167 girls using BsmI, TaqI and ApaI restriction enzymes. Bone mass at the spine, hip, forearm and total body, and lean mass were measured by DXA at baseline and at one year. RESULTS After one year, VDR gene polymorphisms using Bsm1 and TaqI restriction enzymes were associated with percent changes in bone area, BMC and BMD at multiple skeletal sites in the Vitamin D3 group but not in the placebo group. The least increments were observed in the BB and tt genotypes. No similar effect was observed with ApaI enzyme. This relationship between VDR genotypes and changes in BMD and BMC remained significant after adjustment for puberty, changes in lean mass, height and bone area. CONCLUSION VDR gene polymorphisms influence the skeletal response to vitamin D supplementation in healthy adolescent girls.

Apolipoprotein E Gene Polymorphism and Allele Frequencies in the Lebanese Population

Apolipoprotein E (ApoE) genotypes were studied in order to determine the prevalence in the Lebanese population and compare it with other populations. DNA from 160 unrelated healthy donors from our HLA-bank was used. ApoE genotype was determined using the CardioVascular Disease (CVD) StripAssay (this assay is based on a Polymerase Chain Reaction-Reverse Hybridization technique). The prevalence of genotypes E3/3, E3/4, and E2/3 was found to be 69%, 26%, and 22%, respectively, and 0.6% for each of E2/4 and E4/4 genotypes. The Lebanese population tested showed similarities to earlier reported ApoE genotypic distributions (high E3 allele frequency) but also peculiar differences especially to some Arabic countries (total absence of E2 allele among Saudis) and other populations. This is the first report from Lebanon that will serve as a template for future investigations of the prevalence of ApoE alleles in association with various clinical entities.

Prevalence and determinants of suicide ideation among Lebanese adolescents: results of the GSHS Lebanon 2005.

The current study examined prevalence and risk factors for suicide ideation in 5038 Lebanese adolescents using Global School Health Survey data. Around 16% of Lebanese adolescents thought of suicide. Multivariate logistic regression models showed that risk factors for suicide ideation included poor mental health (felt lonely, felt worried, felt sad or hopeless), substance use (got drunk, used drugs), victimization (was bullied, was sexually harassed), and lack of parental understanding. Recommendations for future research and interventions are discussed.

Distribution of hepatitis C virus genotypes among injecting drug users in Lebanon

BackgroundThe aim of this study is to determine the prevalence of anti-HCV among injecting drug users (IDUs) in Lebanon, to establish the current prevalence of HCV genotypes in this population and to determine whether demographic characteristics and behavioral variables differ between participants who were HCV-RNA positive and those who were HCV-RNA negative or between the different genotypes. Participants were recruited using respondent-driven sampling method. The blood samples were collected as dried blood spots and then eluted to be tested for HCV, HBV and HIV by ELISA. Anti-HCV positive samples were subjected to RNA extraction followed by qualitative detection and genotyping.ResultsAmong 106 IDUs, 56 (52.8%) were anti-HCV-positive. The two groups did not differ in terms of age, marital status, and nationality. As for the behavioral variable, there was a trend of increased risky behaviors among the HCV-RNA positive group as compared to the HCV-RNA negative group but none of the variables reached statistical significance. Half (50%) of the 56 anti-HCV-positive were HCV-RNA positive. Genotype 3 was the predominant one (57.1%) followed by genotype 1 (21%) and genotype 4 (18%).ConclusionsThe predominance of genotype 3 seems to be the predominant genotype among IDUs in Lebanon, a situation similar to that among IDUs in Western Europe. This study provides a base-line against possible future radical epidemiological variant that might occur in IDUs.

High Prevalence of MTHFR Gene A1298C Polymorphism in Lebanon

BACKGROUND Mutations in the 5,10-methylenetetrahydrofolate reductase (MTHFR) gene could reduce the enzyme activity and lead to hyperhomocysteinemia, a condition that has been associated with several vascular conditions, in particular, coronary artery disease and deep vein thrombosis. AIM The aim of this study was to assess the prevalence of the two most common polymorphisms, C677T and A1298C, which have not been well studied in the Lebanese population. METHODS We randomly selected 205 healthy individuals originating from different Lebanese provinces and religious communities. The CVD StripAssay was used to test for MTHFR gene polymorphisms. RESULTS We found that for C677T, the prevalence of C/C, C/T, and T/T genotypes was 65.3%, 30.8%, and 3.9%, respectively, with an overall carrier rate of 34.6% and allelic frequency of 0.19. However, the A1298C genotypic prevalence of A/C, A/A, and C/C was 50.2%, 25.9%, and 23.9%, respectively, with an overall carrier rate of 74.14% and an allelic frequency of 0.49. CONCLUSIONS Compared to all other populations reported so far, the Lebanese population harbors the highest prevalence of the MTHFR A1298C polymorphism. This is an important finding to be followed in terms of clinical significance and sheds light on an additional unique genetic feature in this community.

Angiotensin-converting enzyme gene polymorphism and allele frequencies in the Lebanese population: prevalence and review of the literature.

We studied the distribution of the D/D, I/D, and I/I genotypes of the angiotensin-converting enzyme (ACE) in a sample of healthy Lebanese individuals to assess their prevalence and compare them with other populations. ACE genotypes were determined using the Cardiovascular Disease (CVD) StripAssay, which is based on a Polymerase Chain Reaction-Reverse hybridization technique. DNA from 133 unrelated healthy donors from our HLA-bank was used. The prevalence of D/D, I/D, and I/I genotypes was found to be 39.1, 45.1, and 15.8% respectively, with D and I allelic frequency of 61.7 and 38.3%, respectively. The sampled Lebanese population showed ACE genotypic distributions similar to Caucasians; however, with tendency towards harboring high D allele frequency together with a low I allele frequency just like the Spanish population. This first report from Lebanon will serve as a baseline statistical data for future investigations of the prevalence of ACE genotypes in association with various clinical entities notably cardiovascular diseases. The medical literature was also reviewed in this context.

Macular ultrastructural features in amblyopia using high-definition optical coherence tomography

Purpose To study macular morphology in amblyopic eyes using high-definition spectral domain optical coherence tomography (SD-OCT) and to compare the findings with fellow eyes. Methods This was a prospective institutional study of patients ≥6 years of age with unilateral amblyopia. Enhanced high-definition single line macular scans of amblyopic eyes were obtained using SD-OCT and compared with fellow eyes. Scans were evaluated qualitatively for structural differences. Central foveal thickness was measured and areas of the different retinal layers were computed within 500 µm from the foveal centre nasally and temporally. Results Forty-five patients with unilateral amblyopia were included: 25 with strabismic and 20 with anisometropic amblyopia with a mean age of 24.8 years. Qualitatively, the bulge in the inner segment/outer segment junction of the central fovea was noted to be attenuated or absent in 60% of amblyopic eyes compared with 29% of normal eyes, p=0.02. Also, amblyopic eyes demonstrated a shallow foveal pit compared with normal fellow eyes. Mean foveal thickness was significantly increased in amblyopic (228.56 µm) versus fellow eyes (221.72 µm), p=0.03. Upon exploring different retinal layers, the temporal inner nuclear layer area was increased (p=0.04) while the outer nuclear layer area was decreased (p=0.04) in amblyopic eyes compared with fellow eyes. Conclusions Using enhanced high-definition SD-OCT, amblyopic eyes demonstrated qualitative and quantitative differences in macular features, possibly representing signs of immaturity compared with normal fellow eyes.