Nicolaas Nagelkerke
United Arab Emirates University
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Bone | 2006
Hussein Saadi; Nicolaas Nagelkerke; Sheela Benedict; Qazaq Hs; Erica Zilahi; Mohammad K. Mohamadiyeh; Abdulrahim I. Al-Suhaili
OBJECTIVES To determine factors influencing serum 25 hydroxyvitamin D (25OHD) concentration and relationships between serum 25OHD concentration, bone turnover markers, bone mineral density (BMD), and vitamin D receptor (VDR) genotype in Emirati women. METHODS Serum 25OHD, parathyroid hormone (PTH), osteocalcin (OC), vitamin D binding protein (VDBP), and urinary deoxypyrdinoline (UDPD) concentrations and VDR genotype were determined in Emirati women volunteers who were participating in a study aiming at establishing a reference database for BMD. RESULTS Serum 25OHD concentration in the 259 women volunteers was 25.3 +/- 10.8 nmol/l (mean +/- SD), and all had vitamin D deficiency (25OHD <80 nmol/l). Mean serum 25OHD was highest in April (29.2 +/- 13.0 nmol/l), which marks the end of the short and cooler winter season, and lowest in August (18.2 +/- 5.9 nmol/l). No significant difference in 25OHD concentration was noted among Emirati women wearing different dress styles, but the mean serum 25OHD was significantly lower in comparison with non-Arab Caucasian women volunteers who dressed in a Western style (P < 0.001). Serum 25OHD correlated positively with age (r = 0.2), number of pregnancies (r = 0.16), dietary vitamin D intake (r = 0.15), serum calcium (r = 0.14), phosphorus (r = 0.14), VDBP (r = 0.15), and urinary calcium/creatinine (r = 0.2), and inversely with PTH (r = -0.22), OC (r = -0.13), and UDPD/creatinine (r = -0.15); P < 0.05 for all correlations. Multiple linear regression analysis showed that age, dietary vitamin D intake, multivitamin intake, and cooler season were independent positive predictors of serum 25OHD concentration (R(2) = 0.18). The frequencies of VDR genotypes were 36% GG, 44.1% AG, and 19.9% AA. Allele frequencies were 58% for G allele and 42% for A allele and were in Hardy-Weinberg equilibrium (x(2) = 1.44; P > 0.1). There was no statistically significant influence of VDR genotype on bone turnover or BMD. CONCLUSIONS Vitamin D deficiency is highly prevalent in Emirati women and appears largely attributable to insufficient sunlight exposure. It is associated with increased bone turnover. VDR genotype does not appear to influence bone turnover markers or BMD in Emirati women.
Diabetes Research and Clinical Practice | 2008
Hussein Saadi; Nicolaas Nagelkerke; S. George Carruthers; Sheela Benedict; Samar Abdulkhalek; Richard L. Reed; Miodrag L. Lukic; M. Gary Nicholls
AIMS The prevalence of type 2 diabetes mellitus (DM) among Emirati subjects is one of the highest in the world. This has been attributed to rising prevalence of obesity acting on genetically susceptible individuals. We analyzed the associations between TCF7L2 polymorphism and DM, metabolic syndrome, and markers of beta cell function and insulin resistance in a population-based sample of Emirati subjects. METHODS We genotyped the two TCF7L2 single nucleotide polymorphisms (SNPs) rs12255372 and rs7903146 in 368 adult subjects. Homeostatic model assessment (HOMA) was used to assess beta cell function (HOMA2-%B) and insulin resistance (HOMA2-IR). The SNP genotypes were analyzed against disease stage [normal glucose=0 (n=188), pre-diabetes=1 (n=85), and DM=2 (n=95)] and against clinical and biochemical measures. Age and sex were included as covariates in all association analyses. Additional adjustments were made for body mass index (BMI) and waist circumference in several analyses. RESULTS Diabetes disease stage was marginally significantly associated with the frequency of the T variant at rs12255372 (p=0.057; adjusted p=0.017) but not at rs7903146 (p=0.5; adjusted p=0.2). Comparison between subjects with normal glucose and the combined DM/pre-diabetes showed a significant association with rs12255372 (OR 1.47, CI 1.04-2.08; p=0.03) but not with rs7903146 (OR 1.16, CI 0.81-1.64; p=0.4). We found no association with metabolic syndrome, or with insulin and glucose levels, HOMA2-%B or HOMA2-IR. The age-standardized prevalence rate for metabolic syndrome was 43.9% in men and 42.1% in women. CONCLUSION These data suggest that TCF7L2 variants are associated with increased risk for DM in Emirati subjects. We also demonstrate a high prevalence of the metabolic syndrome in this population.
The review of diabetic studies : RDS | 2008
Juma M. Alkaabi; Fatma Al-Maskari; Hussein Saadi; Bachar Afandi; Hasratali Parkar; Nicolaas Nagelkerke
OBJECTIVES The aim of this study was to assess dietary practices and risk profile (hypertension, obesity, lipid profile and glycemic control) among people with diabetes in Al-Ain District, United Arab Emirates (UAE). METHODS During 2006, we performed a cross-sectional study of diabetic patients attending diabetic outpatient clinics at Tawam Hospital and primary health care centers in Al-Ain District. Subjects completed an interviewer-administered questionnaire, blood pressure, body mass index, percentage body fat and abdominal circumference were measured and recorded and the most recent HbA1c levels and fasting lipid profile were identified. RESULTS A sample of 409 diabetic patients was recruited, 50% of whom were illiterate. Only 24% read food labeling. 76% reported being unable to distinguish clearly between low and high carbohydrate index food items and no one reported counting calorie intake. 46% reported that they had never been seen by dietician since their diagnosis. Their overall risk profile, notably body weight, lipid profile and blood pressure, was very unfavorable; more than half of the study sample had uncontrolled hypertension and uncontrolled lipid profile and the majority was overweight (36%) or obese (45%). Abdominal obesity was particularly common (59%). Only 31% had an HbA1c of less than 7%. CONCLUSIONS The dietary practices of diabetic patients in the UAE are inadequate and need improvement.
PLOS ONE | 2013
Abdulla Shehab; Bayan Al-Dabbagh; Khalid F. AlHabib; Alawi A. Alsheikh-Ali; Wael Almahmeed; Kadhim Sulaiman; Ahmed Al-Motarreb; Nicolaas Nagelkerke; Jassim Al Suwaidi; Ahmad Hersi; Hussam Al Faleh; Nidal Asaad; Shukri Al Saif; Haitham Amin
Background Gender-related differences in mortality of acute coronary syndrome (ACS) have been reported. The extent and causes of these differences in the Middle-East are poorly understood. We studied to what extent difference in outcome, specifically 1-year mortality are attributable to demographic, baseline clinical differences at presentation, and management differences between female and male patients. Methodology/Principal Findings Baseline characteristics, treatment patterns, and 1-year mortality of 7390 ACS patients in 65 hospitals in 6 Arabian Gulf countries were evaluated during 2008–2009, as part of the 2nd Gulf Registry of Acute Coronary Events (Gulf RACE-2). Women were older (61.3±11.8 vs. 55.6±12.4; P<0.001), more overweight (BMI: 28.1±6.6 vs. 26.7±5.1; P<0.001), and more likely to have a history of hypertension, hyperlipidemia or diabetes. Fewer women than men received angiotensin-converting enzyme inhibitors (ACE), aspirin, clopidogrel, beta blockers or statins at discharge. They also underwent fewer invasive procedures including angiography (27.0% vs. 34.0%; P<0.001), percutaneous coronary intervention (PCI) (10.5% vs. 15.6%; P<0.001) and reperfusion therapy (6.9% vs. 20.2%; P<0.001) than men. Women were at higher unadjusted risk for in-hospital death (6.8% vs. 4.0%, P<0.001) and heart failure (HF) (18% vs. 11.8%, P<0.001). Both 1-month and 1-year mortality rates were higher in women than men (11% vs. 7.4% and 17.3% vs. 11.4%, respectively, P<0.001). Both baseline and management differences contributed to a worse outcome in women. Together these variables explained almost all mortality disparities. Conclusions/Significance Differences between genders in mortality appeared to be largely explained by differences in prognostic variables and management patterns. However, the origin of the latter differences need further study.
Journal of Environmental Science and Health Part A-toxic\/hazardous Substances & Environmental Engineering | 2008
Yousef M. Abdulrazzaq; Nawal Osman; Nicolaas Nagelkerke; Melita Kosanovic; Abdu Adem
A wide variation in the composition of breast milk has been reported from various countries. This study was undertaken to determine the trace element content of breast milk and plasma in lactating women. Mothers of children 4 weeks to 80 weeks in age, were studied. Blood and breast milk from the mothers were analysed for trace element content. Prepared samples were analysed using ICP-MS. 209 women agreed to take part in the study, 68 of whom were from the UAE and 124 were other nationalities (17 did not fill the this part of the questionnaire). Ninety-seven infants were male. The concentration of different trace elements in blood and breast milk were little different between women from the UAE and those from outside the UAE. Molybenum, chromium and arsenic significantly increased with increasing age of the infant, while manganese, copper and zinc significantly decreased with increasing age of the infant. The trace element concentrations of breast milk and maternal blood were comparable to published values. Normal values for plasma and breast milk trace metal concentrations have been obtained for UAE women.
The Review of Diabetic Studies : RDS | 2009
Juma M. Alkaabi; Fatma Al-Maskari; Hussein Saadi; Bachar Afandi; Hasratali Parkar; Nicolaas Nagelkerke
OBJECTIVES This study was designed to assess the physical activity practice among type 2 diabetic patients in the United Arab Emirates (UAE). METHODS This is a cross-sectional study of type 2 diabetic patients who participated in the outpatient clinics in Al-Ain District, during 2006. The patients completed an interviewer-administered questionnaire, and measurements of blood pressure, body mass index, body fat, abdominal circumference, glycemic control (HbA1c), and fasting lipid profile. RESULTS Of the 390 patients recruited, only 25% reported an increase in their physical activity levels following the diagnosis of diabetes, and only 3% reported physical activity levels that meet the recommended guidelines. More than half of the study subjects had uncontrolled hypertension (53%) and unacceptable lipid profiles; 71% had a high low-density lipoprotein (LDL), 73% had low high-density lipoprotein (HDL), and 59% had hypertriglyceridemia. Forty-four percent were obese and a further 34% were overweight. Abdominal obesity was also common (59%). Only 32% had an acceptable glycemic control. CONCLUSIONS The physical activity practice of type 2 diabetic patients in the UAE is largely inadequate to meet the recommended level necessary to prevent or ameliorate diabetic complications. Interventions aiming at overcoming the barriers to physical activity are urgently needed.
PLOS ONE | 2014
Abdishakur Abdulle; Abdulla Aljunaibi; Nicolaas Nagelkerke
Objectives To estimate the prevalence of high blood pressure (BP) and its relationship with obesity among children and adolescents. Methodology/Principal Findings In this cross-sectional population (Emirati) representative study, we invited a random sample of 1600 students (grades 1–12) attending 23 out of all 246 schools in the Emirate of Abu Dhabi, United Arab Emirates. But analysis was restricted to Emirati nationals aged 6–17 years. We measured BP, height, weight, waist circumferences (WC), and calculated body mass index (BMI) by standard methods. BP levels ≥90th percentile but <95th percentile and ≥ 95th for age, sex, and height (CDC percentiles) were classified as pre-hypertension (pre-HTN) and hypertension (HTN), respectively. Associations between BP, age, BMI, WC, and sex, were investigated by (multiple) linear regression methods. A total of 999 (47% girls) students provided complete results. The prevalence of pre-HTN was 10.5% and 11.4% and the prevalence of HTN was 15.4% and 17.8% among boys and girls, respectively. The prevalence of systolic/diastolic HTN was 14.4%/2.5% and 14.8/7.4% among boys and girls, respectively. BMI CDC percentile was positively correlated with WC percentile (r = 0.734, p<0.01), and both systolic (r = 0.34, p<0.001) and diastolic (r = 0.21, p<0.001) standardized BP. WC percentile was less strongly correlated with standardized SBP (r = 0.255, p<0.01) and DBP (r = 0.175, p<0.01) than BMI. Conclusions/Significance The prevalence of elevated BP, notably systolic was significantly high among the Emirati children and adolescents in Abu Dhabi. High BP was strongly related to body weight, and appears more strongly associated with BMI than WC. Further studies are required to investigate the impact of childhood obesity on HTN.
Annals of Human Genetics | 2009
Yousef M. Abdulrazzaq; Ahmed Ibrahim; Abdullah I Al-Khayat; Nicolaas Nagelkerke; Bassam R. Ali
This study was conducted to determine the prevalence of alkaptonuria in the UAE population and to identify the genotype of affected individuals. In a 3 stage sampling technique 2981 pupils from Government schools in Al Ain and private schools in Dubai were selected to take part in the study, of whom 2857 provided urine samples. Urine collected was analysed for homogentisic acid by gas chromatography‐mass spectrometry. Genomic DNA was isolated from the white blood cells of all family members of the affected case following standard established protocols. Specific PRC primers were designed to amplify all 14 exons of the HGD gene with the flanking intronic sequences including the splice site sequences. 2857 children returned a viable urine sample, of which one was highly positive for homogentisic acid. All 12 members of this girls family were studied and one, a 22 year old brother, was found to excrete HGA. Another, a sister who had not provided a urine sample, was discovered by genetic testing. There were no complaints of joint pain or other symptoms in any member of this family. Parents were first cousins. We found a single nucleotide deletion c.342delA, located in exon 3, which resulted in a frameshift at amino acid position 58 (p.Arg58fs or p.R58fs). Alkaptonuria may be more common than it is thought to be with an allele prevalence estimated at 0.0107 (95% CI 0.000392 – 0.03473). The R58fs mutation is old, perhaps having occurred several thousand years ago, and has spread over a large geographical area.
Acta Paediatrica | 2008
Yousef M. Abdulrazzaq; Asma Al Kendi; Nicolaas Nagelkerke
This study was undertaken to determine how mothers soothed their crying infants. A total of 1137 mothers of different cultural backgrounds were approached, 998 agreed to participate in the study, but only 716 completed the questionnaire through a telephone interview. Analysis was restricted to 702 mothers from the UAE nationality, other Arabs, other Muslims, Indians and Philippinos. The questionnaire contained 23 questions on different soothing methods. The most common soothing method was breast‐feeding (99.1%), followed by holding and carrying the infant (96.9%), letting infant suck on his thumb or finger (87.3%), herbal tea (65%), night bottle (42.1%) and swaddling infant (19.5%). Over 90% of mothers of all nationalities, preferred not to use pacifiers. Soothing herbs were often used, with the commonest being anise (165 mothers used anise). Fennel tea was also used by a substantial number of mothers (75), with gripe water (64), cumin (33), chamomile (32), mint (22) and fenugreek (16) making up most of the rest.
The Review of Diabetic Studies : RDS | 2010
Hussein Saadi; Juma M. Alkaabi; Benbarka M; Khalili A; Almahmeed W; Nicolaas Nagelkerke; Abdel-Wareth L; Al Essa A; Yasin J; Bayan Al-Dabbagh; Kazam E
AIMS To investigate the prevalence of undiagnosed type 2 diabetes (T2D) at primary health care (PHC) clinics, and to assess the quality of care of diabetic patients followed at a tertiary hospital diabetes center in Abu Dhabi, United Arab Emirates (UAE). METHODS Between May 2009 and October 2010, adult patients attending two PHC clinics, and adult diabetic patients attending the diabetes center, were invited to participate in the study. After overnight fast, participants returned for interview and laboratory tests. Undiagnosed T2D was defined by FPG ≥ 7.0 mmol/l or HbA1c ≥ 6.5%. Quality of care was assessed by reported care practices and achievement of internationally recognized targets. RESULTS Out of 239 patients at PHC clinics without history of T2D, 14.6% had undiagnosed T2D, and 31% had increased risk of diabetes (FPG 5.6-7.0 mmol/l or HbA1c 5.7-6.5%). The independent predictors of undiagnosed T2D were age (adjusted OR per year 1.07, 95% CI 1.04-1.11, p < 0.001) and BMI ≥ 25 (adjusted OR 4.2, 95% CI 0.91-19.7, p = 0.033). Amongst all 275 diagnosed T2D patients, including those attending PHC clinics and those followed at the diabetes center, it was found that 40.1% followed dietary recommendations, 12% reported visiting a diabetes educator, 28.2% walked for exercise, and 13.5% attained recognized targets of HbA1c < 7%, blood pressure < 130/80 mmHg, and LDL cholesterol < 2.6 mmol/l. CONCLUSIONS Almost half of the adult patients attending PHC clinics had undiagnosed T2D, or increased diabetes risk. Care practices, and achievement of treatment targets, were suboptimal.