Association of Protein Tyrosine Phosphatase Receptor Type D and Serine Racemase Genetic Variants with Type 2 Diabetes in Malaysian Indians.

Introduction: Type 2 diabetes (T2D) candidate genes, protein tyrosine phosphatase receptor type D (PTPRD), and serine racemase (SRR) were suggested by a genome-wide association study (GWAS) in the Chinese population. Association studies have been replicated among East Asian populations. The association of PTPRD and SRR genetic variants with T2D in Southeast Asian populations still needs to be studied. This study aimed to investigate the association of PTPRD and SSR genetic variants with T2D in Malaysian Indian subjects. Methods: The single nucleotide polymorphisms (SNPs) of PTPRD (rs649891 and rs17584499) and SRR (rs4523957, rs391300, and rs8081273) were genotyped in 397 T2D and 285 normal Malaysian Indian subjects. Results: The homozygous dominant genotype of rs17584499 is frequent in diabetic patients (56.5%) compared to normal subjects (47.3%). In contrast, the homozygous recessive genotype of rs8081273 is more frequent among normal subjects (12.5%) than diabetic patients (5.6%). The dominant genetic model showed that PTPRD rs17584499 (CC) is a risk factor for T2D (OR = 1.42, P = 0.029), whereas the recessive genetic model showed that SRS SNP rs8081273 was protective for T2D (OR = 0.42, P = 0.003). Conclusion: This study confirmed the association of PTPRD rs17584499 genetic variations with T2D in Malaysian Indians. While the SRR rs8081273 (TT) genotype showed protection against T2D, more investigation in different populations is required to confirm this protection.

Plasma Lipocalin-2 and Adiponectin are Affected by Obesity Rather Than Type 2 Diabetes Mellitus per se.

PURPOSE: Changes in plasma adipocytokines and inflammatory markers in type 2 DM remain controversial as to whether they are due to obesity or directly associated with the diabetic state. Our objective was to study the effect of obesity and diabetes on plasma lipocalin-2 (LCN2), adiponectin, and interleukin-1ß (IL-1ß) by comparing their levels in non-diabetic obese subjects and non-obese type 2 DM patients, as well as determining the association of these adipocytokines with metabolic syndrome factors and diabetic parameters. PATIENTS AND METHODS: In this study, 85 Yemeni male volunteers aged 30-60 years old were enrolled, 25 of whom were healthy subjects with BMI < 25 kg/m2 served as control; 30 non-diabetic obese subjects (BMI ≥ 30 kg/m2 and FBG < 6.1 mmol/l); and 30 non-obese type 2 DM patients (BMI < 25 kg/m2 and FBG > 7 mmol/l). RESULTS: Lipocalin-2 and adiponectin were significantly (p = 0.043 and p = 0.034) lower in non-diabetic obese subjects by 16.2% and 29.7% with respect to control group, with no effect in the non-obese type 2 DM patients. Moreover, LCN2 was significantly (p = 0.04) lower in the non-diabetic obese subjects by 15.8% as compared with the non-obese type 2 DM patients, with no significant difference in adiponectin levels. In contrast, serum IL-1ß was significantly (p = 0.001 and p = 0.003) higher in both non-diabetic obese subjects and the non-obese type 2 DM patients by 76.5% and 67.7% as compared to control group. The significant decrease in both LCN2 and adiponectin and the significant increase in IL-1ß in the non-diabetic obese subjects disappeared upon adjustment for waist circumference (WC). In contrast, the significant increase in IL-1ß in the non-obese Type 2 DM patients was not affected upon adjustment for WC. CONCLUSION: Plasma LCN2 and adiponectin were not affected by diabetes per se, suggesting that the observed changes in LCN2 and adiponectin in type 2 DM may be due to obesity rather than the diabetic state, whereas IL-1ß levels were affected by both obesity and diabetes.

Latent Autoimmune Diabetes in Adults (LADA) and its Metabolic Characteristics among Yemeni Type 2 Diabetes Mellitus Patients.

PURPOSE: Although there is ample data about the prevalence of diabetes in the Middle East, little is known about the prevalence and features of autoimmune diabetes in this region. The aim of this study was to investigate the prevalence and metabolic characteristics of latent autoimmune diabetes in adults (LADA) amongst Yemeni Type 2 DM patients. PATIENTS AND METHODS: In this cross-section study, 270 Type 2 DM patients aged 30-70 years were recruited from the National Diabetes Center, Al-Thowra Hospital, Sana'a city, during the period November 2015 to August 2016. All Type 2 DM patients were diagnosed within 5 years and who did not require insulin for a minimum of 6 months following diagnosis. Levels of glutamic acid decarboxylase autoantibodies (GADA) were measured in all patients, and LADA was diagnosed in patients testing positive for anti-GAD antibodies. Further, biochemical analysis was carried out including fasting blood glucose (FBG), glycated haemoglobin (HbA1c), insulin, and lipid profile. Insulin resistance (HOMA-IR) and ß-cell function (HOMA-ß) were calculated. RESULTS: The prevalence of LADA, as defined by GADA-positive, amongst patient with Type 2 DM was 4.4%; with no significant difference in the prevalence between male (5.8%) and female (3.4%). LADA patients were younger than GADA-negative Type 2 DM. Body mass index, waist circumference, insulin and HOMA-ß were significantly lower in LADA patients, whereas triglyceride, cholesterol, HDL-c and HOMA-IR were non-significantly lower with respect to Type 2 DM. In contrast, FBG and HbA1c were significantly higher in LADA patients. Moreover, the prevalence of metabolic syndrome was significantly lower in LADA as compared with Type 2 DM. Only 2 out of the 12 GADA-positive (16.7%) were on insulin treatment at the time of the study. CONCLUSION: The prevalence of LADA in Yemeni Type 2 DM is lower than many of those reported in the literature, with no gender preference. Metabolic syndrome was significantly lower in LADA patients. Patients with LADA share insulin resistance with Type 2 DM but display a more severe defect in ß-cell function, thus highlighting the importance of an early diagnosis of LADA, to correctly treat LADA patients, allowing safe and effective therapies.

Impact of triglycerides and waist circumference on insulin resistance and ß-cell function in non-diabetic first-degree relatives of type 2 diabetes.

BACKGROUND: Although there is abundant evidence indicating the relative contribution of insulin resistance (HOMA-IR) and ß-cell dysfunction (HOMA-ß) among first-degree relatives (FDRs) of Type 2 DM patients, few studies reported the association between HOMA-IR and HOMA-ß with metabolic syndrome. Our objective was to evaluate the impact of metabolic syndrome factors on HOMA-IR, HOMA-ß and glycoproteins in non-diabetic FDRs. METHODS: In this study, 103 Yemeni male subjects aged 25-42 years, with BMI < 25 kg/m2 were examined, 39 of whom were normal subjects with no family history of diabetes served as control and 64 subjects were non-diabetic FDRs of Type 2 DM patients. RESULTS: Both glycoproteins, glycated haemoglobin (HbA1c) and fructosamine as well as insulin, HOMA-IR and HOMA-ß were significantly (p = 4.9 × 10-9; 6.0 × 10-8; 6.6 × 10-12; 1.3 × 10-7; 5.5 × 10-12, respectively) higher in non-diabetic FDRs as compared to control group. Fasting plasma glucose, though within normal range, were significantly (p = 0.026) higher in non-diabetic FDRs. Linear regression analysis showed that both TG and WC are the main metabolic syndrome factors that significantly increased HOMA-IR (B = 0.334, p = 1.97 × 10-6; B = 0.024, p = 1.05 × 10-5), HOMA-ß (B = 16.8, p = 6.8 × 10-5; B = 0.95, p = 0.004), insulin (B = 16.5, p = 1.2 × 10-6; B = 1.19, p = 8.3 × 10-6) and HbA1c (B = 0.001, p = 0.034; B = 0.007, p = 0.037). CONCLUSION: Triglyceride and WC are the important metabolic syndrome factors associated with insulin resistance, basal ß-cell function and insulin levels in non-diabetic FDR men of Type 2 DM patients. Moreover, FDRs showed insulin resistance with compensatory ß-cell function (hyperinsulinaemia) suggesting that insulin resistance precede the development of pancreatic ß-cell dysfunction in individuals at risk of Type 2 DM.

Metabolic Syndrome and Prediabetes Among Yemeni School-Aged Children.

PURPOSE: In view of the high rate of obesity and physical inactivity as well as the rising incidence of Type 2 DM among children in the neighboring Gulf countries and Middle East region; the aim of this study was, therefore, to determine the prevalence of metabolic syndrome (MetS) and prediabetes in Yemeni school-aged children. PATIENTS AND METHODS: In this study, 1402 school children aged 12-13 years old (grade 7) were recruited from public schools in the capital Sana'a during the period April-May 2013. Anthropometric measurements and BP were recorded and BMI was calculated. Fasting venous blood (5 mL) was collected for biochemical analysis including FBG, HbA1c, insulin and lipids profile. Insulin resistance (HOMA-IR) and ß-cell function (HOMA-ß) were calculated. RESULTS: The prevalence of prediabetes (as defined by impaired fasting glucose) and MetS (as classified by the IDF 2007) were 0.86% and 0.5%, respectively. Our results also showed 5.21% and 20.26% of the children to have two or one factor(s) of the MetS criteria fulfilled, respectively, with low HDL-c (17%) being the most prevalent MetS component, followed by metabolic glucose (8%), raised TG (5.3%), DBP (1.4%), and high WC (0.5%). Moreover, the prevalence of overweight and obesity was 4.2% and 2.8%, respectively; and about 1.2% of children had abnormal high insulin levels. Children with impaired fasting glucose (IFG) had increased HOMA-IR (p = 0.016) and SBP (p = 0.042) and decreased HDL-c (p = 0.034) and HOMA-ß (p < 0.001); whereas obese children had increased WC (p < 0.001) and TG (p = 0.049). CONCLUSION: The main finding of this study is that Yemeni children are at potential risk of obesity, metabolic syndrome and prediabetes despite their low prevalences. These results highlight the need for early identification and close monitoring of children at risk of later Type 2 DM as an important primary care strategy that can effectively prevent or delay the onset of such condition.

Relationship of metabolic syndrome defined by IDF or revised NCEP ATP III with glycemic control among Malaysians with Type 2 Diabetes.

BACKGROUND: The chronic complications of Type 2 Diabetes (T2D) such as macrovascular disease is amplified with the increase in the number of metabolic syndrome (MetS) risk factors. This research aims to study the relationship of MetS, diagnosed by the International Diabetes Federation (IDF) or revised National Cholesterol Education Programs Adult Treatment Panel III (NCEP ATP III) criteria, with glycemic control, fasting blood glucose (FBG), glycated hemoglobin (HbA1c), C-peptide, and insulin resistance in T2D patients. METHODS: The study is a cross-sectional observational study which, involved 485 T2D patients who are receiving treatment at the University Kebangsaan Malaysia Medical Center (UKMMC), Kuala Lumpur, Malaysia. The MetS among the T2D patients was diagnosed based on IDF and revised NCEP ATP III criteria. C-peptide and HbA1c levels were determined by an automated quantitative immunoassay analyzer and high-performance liquid chromatography, respectively. The MetS factors; FBG, triglyceride, and high-density lipoprotein cholesterol were measured by spectrophotometer. RESULTS: Application of the IDF and revised NCEP ATP III criteria respectively resulted in 73% and 85% of the T2D subjects being diagnosed with MetS. The concordance of these criteria in diagnosing MetS among T2D patients was low (κ = 0.33, P < 0.001). Both IDF and revised NCEP ATP III criteria indicated that T2D patients with 5 MetS factors had higher insulin resistance (P = 2.1 × 10-13; 1.4 × 10-11), C-peptide (P = 1.21 × 10-13; 4.1 × 10-11), FBG (P = 0.01; 0.021), and HbA1c (P = 0.039; 0.018) than those T2D patients without MetS, respectively. CONCLUSION: Although there is a low concordance between IDF and revised NCEP ATP III criteria in the diagnosis of MetS among T2D patients, both criteria showed that T2D patients with 5 MetS factors had higher insulin resistance, C-peptide, FBG, and HbA1c.

Ramadan Intermittent Fasting Affects Adipokines and Leptin/Adiponectin Ratio in Type 2 Diabetes Mellitus and Their First-Degree Relatives.

BACKGROUND: In view of the association of Ramadan intermittent fasting with profound changes in lifestyle both in nondiabetic and diabetic patients, the aim of this study was to investigate the effect of Ramadan fasting on adiponectin, leptin and leptin to adiponectin ratio (LAR), growth hormone (GH), human-sensitive C-reactive protein (hs-CRP), and diabetic and metabolic syndrome factors in patients with Type 2 Diabetes Mellitus (Type 2 DM), their first-degree relatives (FDRs), and healthy controls. METHODS: This cohort study involved 98 Yemeni male subjects aged 30-70 years old: 30 Type 2 DM, 37 FDRs of Type 2 diabetic patients, and 31 healthy control subjects. Subjects' body mass index (BMI), waist circumference (WC), and blood pressure (BP) were measured, and venous blood samples were collected twice: the first samples were collected a couple of days prior to Ramadan fasting (baseline) and the second samples after 3 weeks of fasting. RESULTS: Ramadan fasting did not affect BMI, WC, and BP in Type 2 DM and their FDRs with respect to the baseline levels prior to Ramadan, whereas triglyceride and cholesterol were borderline significantly decreased in Type 2 DM with no effect in FDRs. Fasting blood glucose was not affected in Type 2 DM but was significantly increased in FDRs and control groups, whereas glycated haemoglobin (HbA1c) was slightly decreased in Type 2 DM, FDRs, and healthy controls. C-peptide, insulin, and insulin resistance (HOMA-IR) were significantly increased in Type 2 DM and FDRs, with no effect in the control group, whereas ß-cell function (HOMA-ß) was significantly decreased in FDRs and controls with no change in Type 2 DM. Ramadan fasting significantly decreased GH in both FDRs and control groups, and significantly increased hs-CRP in the control with no effect in Type 2 DM and FDRs. Adiponectin was significantly decreased, and leptin and LAR were significantly increased in Type 2 DM, FDRs, and control groups. CONCLUSION: Ramadan intermittent fasting decreased adiponectin and increased leptin, LAR, insulin, and insulin resistance in both Type 2 DM and FDRs as well as decreased GH in both FDRs and healthy controls and increased hs-CRP in healthy controls. Moreover, Ramadan intermittent fasting neither worsens a patient's glycemic parameters nor improves it, with the exception of a slight improvement in HbA1c in Type 2 DM, FDRs, and healthy controls.

The Yemeni Brown Algae Dictyota dichotoma Exhibit High In Vitro Anticancer Activity Independent of Its Antioxidant Capability.

The aim of this study was to investigate the anticancer and antioxidant activities as well as the safety of the brown algae Dictyota dichotoma of the Western seacoast of Yemen. Cytotoxicity of methanol extract of D. dichotoma and several of its fractions, petroleum ether, chloroform, ethyl acetate, n-butanol, and aqueous extracts against seven different cancer cell lines was determined by crystal violet staining. The antioxidant activity was also assessed using the DPPH radical scavenging assay. Acute toxicity study was performed on rats at increasing doses of the methanol extract. Extracts of D. dichotoma exerted a significant dose-dependent cytotoxicity on the seven tumor cell lines but were generally more selective on MCF-7 and PC-3. Among all fractions, the chloroform fraction of the D. dichotoma displayed the highest cytotoxic activity and was most effective in MCF-7, PC3, and CACO cells (IC50 = 1.93 ± 0.25, 2.2 ± 0.18, and 2.71 ± 0.53 µg/mL, respectively). The petroleum ether fraction was also effective, particularly against MCF-7 and PC-3 (IC50 = 4.77 ± 0.51 and 3.93 ± 0.51 µg/mL, respectively) whereas the activity of the ethyl acetate fraction was more pronounced against HepG2 and CACO (IC50 = 5.06 ± 0.21 and 5.06 ± 0.23 µg/mL, respectively). Of all the extracts tested, the crude methanolic extract of the algae exhibited only a modest antioxidant potential (IC50 = 204.6 ± 8.3 µg/mL). Doses as high as 5000 mg/kg body weight of D. dichotoma methanolic extracts were safe and well tolerated by rats. The overall results showed that D. dichotoma exhibited a significant cytotoxic activity probably due to the occurrence of nonpolar cytotoxic compounds, which is independent of its antioxidant capability.

Impact of Metabolic Syndrome Factors on Testosterone and SHBG in Type 2 Diabetes Mellitus and Metabolic Syndrome.

OBJECTIVE: Several studies have often reported low testosterone and SHBG to be associated with type 2 DM and the metabolic syndrome (MetS). Our objective was to determine the impact of metabolic syndrome and diabetic parameters on testosterone and SHBG in both MetS subjects and type 2 DM patients. METHODS: In this study, 120 Yemeni male aged 30-70 years old were enrolled, 30 of whom were healthy subjects with BMI < 25 kg/m2 that served as control, 30 MetS, 30 type 2 DM without MetS, and 30 type 2 DM with MetS according to IDF criteria. RESULTS: Testosterone (free and total) and SHBG were significantly lower in MetS subjects and modestly reduced in type 2 DM with and without MetS. Stepwise linear regression showed free and total testosterone to be negatively affected by waist circumference, and univariate analysis shows this significant difference to disappear when adjusted for waist circumference. On the other hand, stepwise linear regression showed SHBG to be positively affected by testosterone and age and negatively affected by FBG and TG. Univariate analysis shows this observed significant difference to disappear when adjusted for testosterone. CONCLUSION: Abdominal obesity is a major determinant of low testosterone levels irrespective of diabetes status. Thus, supporting evidence suggesting that the causative relationship between the often low testosterone and type 2 DM might be bidirectional or even multidirectional and interrelated with obesity, MetS, and IR.

Anger, anxiety, and depressive affect as predictors of stress-induced cortisol production in khat and tobacco users.

INTRODUCTION: Glucocorticoid activity is disrupted in substance users including khat chewers who also use tobacco. Anger, dysphoria, and anxiety can mediate this relationship. The aim of this study was to contrast emotion dysregulation and substance use variables as predictors of post-stress cortisol output. MATERIALS AND METHODS: Comparable numbers of males (n = 90) and females (n = 85) including controls, khat only, and concurrent khat and tobacco users participated in a stress study. Depressive affect, anxiety, anger, substance use patterns, and saliva samples were collected following a standardized laboratory stress manipulation. RESULTS: Regression analysis showed that high depression and low anxiety was associated with high post-stress cortisol, but only in co-users of tobacco and khat. Males, but not females, showed a significant association between co-use of khat and tobacco and cortisol, which appears to be mediated by frequency of use. The link between anxiety and post-stress cortisol in the co-users remained significant after controlling for nicotine dependence and substance use frequency. CONCLUSION: Anxiety predicted the neuroendocrine consequences of concurrent use of tobacco and khat above and beyond sex, nicotine dependence, anger, and substance use frequency. Sex differences, however, are related to differences in nicotine dependence.

Chad Genetic Diversity Reveals an African History Marked by Multiple Holocene Eurasian Migrations.

Understanding human genetic diversity in Africa is important for interpreting the evolution of all humans, yet vast regions in Africa, such as Chad, remain genetically poorly investigated. Here, we use genotype data from 480 samples from Chad, the Near East, and southern Europe, as well as whole-genome sequencing from 19 of them, to show that many populations today derive their genomes from ancient African-Eurasian admixtures. We found evidence of early Eurasian backflow to Africa in people speaking the unclassified isolate Laal language in southern Chad and estimate from linkage-disequilibrium decay that this occurred 4,750-7,200 years ago. It brought to Africa a Y chromosome lineage (R1b-V88) whose closest relatives are widespread in present-day Eurasia; we estimate from sequence data that the Chad R1b-V88 Y chromosomes coalesced 5,700-7,300 years ago. This migration could thus have originated among Near Eastern farmers during the African Humid Period. We also found that the previously documented Eurasian backflow into Africa, which occurred ∼3,000 years ago and was thought to be mostly limited to East Africa, had a more westward impact affecting populations in northern Chad, such as the Toubou, who have 20%-30% Eurasian ancestry today. We observed a decline in heterozygosity in admixed Africans and found that the Eurasian admixture can bias inferences on their coalescent history and confound genetic signals from adaptation and archaic introgression.

Positive selection of lactase persistence among people of Southern Arabia.

OBJECTIVE: Frequency patterns of the lactase persistence (LP)-associated -13,915 G allele and archaeological records pointing to substantial role played by southern regions in the peopling and domestication processes that involved the Arabian Peninsula suggest that Southern Arabia plausibly represented the center of diffusion of such adaptive variant. Nevertheless, a well-defined scenario for evolution of Arabian LP is still to be elucidated and the burgeoning archaeological picture of complex human migrations occurred through the peninsula is not matched by an equivalent high-resolution description of genetic variation underlying this adaptive trait. To fill this gap, we investigated diversity at a wide genomic interval surrounding the LCT gene in different Southern Arabian populations. METHODS: 40 SNPs were genotyped to characterize LCT profiles of 630 Omani and Yemeni individuals to perform population structure, linkage disequilibrium, population differentiation-based and haplotype-based analyses. RESULTS: Typical Arabian LP-related variation was found in Dhofaris and Yemenis, being characterized by private haplotypes carrying the -13,915 G allele, unusual differentiation with respect to northern groups and conserved homozygous haplotype-blocks, suggesting that the adaptive allele was likely introduced in the Arabian gene pool in southern populations and was then subjected to prolonged selective pressure. CONCLUSION: By pointing to Yemen as one of the best candidate centers of diffusion of the Arabian-specific adaptive variant, obtained results indicate the spread of indigenous groups as the main process underlying dispersal of LP along the Arabian Peninsula, supporting a refugia model for Arabian demic movements occurred during the Terminal Pleistocene and Early Holocene.

Association of adipokines, leptin/adiponectin ratio and C-reactive protein with obesity and type 2 diabetes mellitus.

OBJECTIVE: Alterations in plasma adipokines and/or inflammatory parameters in Type 2 DM remain vague as to whether they are due to obesity and/or directly associated with the diabetic state. Our objective was to compare plasma adiponectin, leptin, leptin/adiponectin ratio (LAR) and hs-CRP in obese non-diabetic subjects and non-obese Type 2 DM patients, as well as determining the association of these adipokines with MetS and diabetes-related quantitative traits. METHODS: In this study, 92 Yemeni male volunteers aged 25-60 years old were enrolled, 31 of whom were healthy subjects with BMI < 25 kg/m(2) served as control; 30 non-diabetic obese subjects BMI ≥ 30 kg/m(2) and FBG < 6.1 mmol/l; and 31 non-obese Type 2 DM with FBG > 7 mmol/l and BMI < 25 kg/m(2). RESULTS: Adiponectin was lower in obese subjects, with no differences between non-obese Type 2 DM patients and controls. In contrast, leptin, LAR and hs-CRP were higher in both obese subjects and non-obese Type 2 DM patients. Linear regression analysis showed adiponectin to be associated negatively with BMI, waist circumference, insulin, HOMA-ß and HOMA-IR; whereas leptin, LAR and hs-CRP were associated positively with BMI, waist circumference, TG, FBG, insulin, HOMA-ß and HOMA-IR. Moreover, adiponectin negatively correlated with leptin, LAR and hs-CRP; whereas leptin and LAR positively correlated with hs-CRP and with each other. CONCLUSION: Plasma adiponectin is not affected by diabetes per se, suggesting that its alterations in Type 2 DM may be due to obesity and may be an important link between adiposity, IR and Type 2 DM.

Concurrent tobacco and khat use is associated with blunted cardiovascular stress response and enhanced negative mood: a cross-sectional investigation.

OBJECTIVES: Khat (Catha edulis), an amphetamine-like plant, is widely used in East Africa and the Arabian Peninsula and is becoming a growing problem in other parts of the world. The concurrent use of tobacco and khat is highly prevalent and represents a public health challenge. We examined for the first time associations of the concurrent use of tobacco and khat with psychophysiological responses to acute stress in two sites in Yemen. METHODS: Participants (N = 308; 135 women) included three groups: users of khat and tobacco, users of khat alone, and a control group (nonsmokers/nonusers of khat). These individuals completed a laboratory session in which blood pressures (BP), heart rate, and mood measures were assessed during rest and in response to acute stress. RESULTS: Concurrent use of khat and tobacco was associated with attenuated systolic BP, diastolic BP, and heart rate responses to laboratory stress (ps < 0.05) and with increased negative affect relative to the control group (ps < 0.05). CONCLUSIONS: Results demonstrated blunted cardiovascular responses to stress and enhanced negative affect in concurrent khat and tobacco users. These findings extend previous studies with other substances and suggest that adverse effects of khat use may lie in its association with the use of tobacco.

Catha Edulis (Khat) Chewing Decreases Serum Levels of Iron, Ferritin and Vitamin B12 and Increases Folic Acid.

BACKGROUND: Catha edulis (Khat) is customarily chewed to attain a state of stimulation and reduce physical fatigue. In view of the reported common adverse effects of Khat, the aim of this study was to evaluate the levels of iron, ferritin, folic acid, vitamin B(12) and body mass index (BMI) as nutritive indicators in Yemeni Khat chewers. METHODS: This study was a prospective cohort study, carried out on 90 male workers aged 19 - 23 years old; 45 were healthy non-Khat chewers serving as control group and 45 were regular Khat chewers. Serum iron, ferritin, folic acid, vitamin B(12) and body mass index were measured at baseline and after a year of follow up. RESULTS: Serum iron and BMI were significantly (p < 0.01) lower at baseline in Khat chewers by 9 % and 6 %, respectively; whereas ferritin, folic acid and vitamin B(12) were non-significantly different from non-Khat chewers. In the follow-up one year later, serum iron, ferritin, vitamin B(12) and BMI were significantly (p < 0.001) lower in Khat chewers by 19.0, 31.4, 20.6 and 10.7 %; whereas folic acid was significantly (p = 0.007) higher by 26.7 %. Comparison within groups showed serum iron, ferritin, and BMI to be significantly (p < 0.01) decreased after one year in the Khat chewers with respect to its baseline; whereas folic acid significantly (p < 0.001) increased. CONCLUSION: This study shows Khat chewers to be more susceptible to malnutrition, which should be considered by the general population and the public health authorities.

Effects of chronic khat use on cardiovascular, adrenocortical, and psychological responses to stress in men and women.

BACKGROUND: Khat is a psychostimulant plant widely used in Africa and its use has been growing rapidly in Europe and North America. OBJECTIVES: We investigated effects of chronic khat (Catha edulis) use on cardiovascular, adrenocortical, and psychological responses to acute stress. METHODS: Chronic khat users and nonusers were compared on physiological measures and mood reports in a cross-sectional, mixed design. Measurements were conducted during 24-hour ambulatory monitoring and during a laboratory session. A total of 152 participants (58 women) were recruited by flyers posted around Sana'a University campus and the surrounding community in Sana'a, Yemen. Salivary cortisol and self-report measures were collected during a 24-hour ambulatory period prior to a lab testing session. In addition, blood pressures (BP), salivary cortisol, and mood measures were assessed during rest and in response to acute mental stress. RESULTS: Khat users exhibited enhanced evening and attenuated morning cortisol levels, reflecting a blunted diurnal pattern of adrenocortical activity compared to nonusers. Khat users reported greater negative affect during the ambulatory period and during the laboratory session. In addition, they exhibited attenuated BP responses to stress. CONCLUSIONS AND SCIENTIFIC SIGNIFICANCE: These novel results demonstrate altered adrenocortical activity and increased dysphoric mood among khat users. The extent to which these associations are due to effects of chronic khat use per se or instead reflect predisposing risk factors for khat use is yet to be determined.

Gender differences in patterns and correlates of khat and tobacco use.

INTRODUCTION: Although research suggests gender differences in patterns of tobacco use, whether gender moderates concurrent use of tobacco and other substances remains unclear. In some parts of Africa and the Middle East, tobacco is often accompanied with khat (Catha edulis), a widely used substance in these regions. The concurrent use of tobacco and khat may represent a public health burden spreading to other countries in Europe and North America. METHOD: A total of 189 participants (69 women) khat users and smokers in Yemen were asked to complete questionnaires that focused on patterns of khat and tobacco use. Chi-square tests, analyses of variance, and correlational analyses were conducted. RESULTS: Reported frequency and intensity of khat and tobacco use were greater among men than in women. Also, reported number of cigarettes smoked during a khat session was higher among men than among women, whereas frequency of waterpipe use during the session was greater among women than among men. Smoking status (daily or occasional) was positively associated with khat use in women only. Age of onset of khat use was inversely related to the number of cigarettes smoked during a khat session and with intensity of khat chewing. The majority of participants reported that they had thought about and have attempted to quit khat and tobacco use. CONCLUSIONS: The results provide evidence for gender differences in patterns of concurrent use of tobacco and khat. Identifying determinants of tobacco and khat use may be useful in reducing the risk of their negative health outcomes.

Distribution of the lactase persistence-associated variant alleles -13910* T and -13915* G among the people of Oman and Yemen.

The high prevalence of lactase persistence (LP) among the people of Saudi Arabia is associated with the -13915(*)G variant allele upstream of the lactase gene (LCT). We, therefore, examined the frequency of the commonly known LP associated SNPs among randomly collected samples from Omani and Yemeni adult populations and obtained further data on the distribution of the two most common LP-associated variants, -13910(*)T and -13915T(*)G, in the Arabian Peninsula. The DNA fragment containing all the reported LP- associated SNPs was amplified and genotyped. The frequency of the -13915(*)G allele was highest among Dhofari Arabs of southern Oman (0.72) followed by Yemeni Arabs (0.54) and Arabs of northern Oman (0.14). It was not detected in Omanis of Asian origin. The frequency of the -13910(*)T allele was extremely low in Arabs of northern and southern Oman (0.00-0.01) and Yemenis (0.002). However, it had a frequency of 0.160 among Omanis of Asian origin. Results show that the highest frequency of the LCT -13915(*)G variant allele appears to be in the south of the Arabian Peninsula with clinal decrease within the Peninsula and further out in surrounding countries.

Khat use and trait anger: effects on affect regulation during an acute stressful challenge.

Khat (Catha edulis) is a widely used stimulating drug often consumed in daily routine in Yemen and East African countries. Chewing khat acutely elicits states of euphoria and feelings of well-being which later shift into emotional instability and low mood. Little is known about emotional regulation in habitual khat chewers. In this study, we compared self-reports on trait anger as well as positive and negative affect responses to a mental arithmetic challenge. Participants included 135 men and women from Yemen who chew khat regularly, occasionally or not at all. Participants attended a laboratory session that involved resting periods and performing a math challenge. Analyses of variance and regression show that regular khat chewing is associated with higher trait anger, more pronounced negative responses during stress and less pronounced positive emotional states. These results suggest that regular khat chewing is associated with disturbances in emotion regulation processes.

Socioeconomic and environmental factors important for acquiring non-severe malaria in children in Yemen: a case-control study.

Little is known about the relative importance of environmental and socioeconomic factors for acquiring malaria in Yemen. A case-control study was conducted to determine the importance of these factors for acquiring malaria among children in Yemen. Cases of non-severe malaria were recruited from health centres; community controls were from the neighbourhood of the cases. Data were collected by personal interview and direct inspection during home visits. In total, 320 cases and 308 controls were recruited. In the multivariate analysis, environmental factors (living near streams and freshwater marshes), earth roofs of houses and history of travel were all significantly and positively associated with the occurrence of malaria, whilst regular spraying with insecticides at home was a protective factor. There was no association with socioeconomic factors, including crowding, education and occupation of parents, and ownership of house assets. An index created based on a number of indicators of wealth showed a significant association with malaria in the univariate analysis but was not significant in the multivariate analysis. Control activities can be targeted on identifiable environmental factors such as stream and freshwater marshes, although this needs further investigation. Extra protective measures may be needed by all those who travel in Yemen.