Assessment of low vitamin D among Saudi Arabians. Did we overshoot the runway?

To compare the performance of 3 commonly used 25-hydroxyvitamin D [25-OHD] assays among a sample of the Saudi population. This cross-sectional study was carried out between January 2011 and December 2012 at King Fahd Hospital of the University, Al-Khobar, Saudi Arabia. After informed consent, blood samples for measurement of 25-OHD level was extracted from 200 adults. The vitamin D level of each individual were determined using chemiluminescence immunoassay [CLIA], radio-immuno assay [RIA], and liquid chromatography-tandem mass spectrometry [LC-MS/MS] assay. Assays were also compared through commonly used cut-points for classification of vitamin D deficiency. Bias between assays was evaluated using Bland-Altman plots. The average age of patients was 45.7 +/- 16.1 years. A significant difference between the assays was found. The mean 25-OHD levels were highest for the LC-MS/MS [21.65 ng/mL, 95% CI 19.74-23.56], intermediate for RIA [16.607 ng/mL, 95% CI 14.87-18.32], and lowest for CLIA method [13.864 ng/mL, 95% CI 12.109-15.618]. Using 30 ng/mL as a cutoff value, only 6% was found to have normal levels of 25-OHD using CLIA, 9% using RIA, and 22% using LC-MS/MS. Levels of 25-OHD and the prevalence of vitamin D deficiency are dependent on the assay used. The reported high prevalence of hypovitaminosis D among the Saudi population can be partially explained by the use of assays that underestimate vitamin D levels

Association of NOD2/CARD15, DLG5, OCTN1 and toll-like receptor 4 gene polymorphisms with inflammatory bowel disease: a university hospital experience

Background: Both genetic and environmental factors play major roles in the development of inflammatory bowel disease [IBD]. Recent studies have identified a number of genetic susceptibility loci for Crohn's disease [CD] and ulcerative colitis [UC]

Objectives: The present study aimed at examining the association of nine polymorphisms in four different genes with the development of CD and UC in a sample of Saudi patients with IBD

Materials and Methods: All gene polymorphisms were identified by polymerase chain reaction and by direct sequencing. Allele and genotype frequencies of polymorphisms of NOD2/CARD15 [R702W, G908R, L1007finsC], Toll-like receptor 4 [TLR4] [D299G, T399I], OCTN promoter [C1672, G207C] and DLG5 [G113A, C4136A] genes were determined in Saudi subjects with CD [51], UC [26] and in 75 normal controls

Results: Out of the nine polymorphisms studied in four loci, only two polymorphisms in two different loci were found to have increased in patients compared with the control subjects. The CT genotype of TLR4 T3991 was over represented in patients with CD or UC compared to that in controls [odds ratios [OR], 5.63:95% confident interval [CI], 1.19-26.69; P = 0.03]. In addition, the GA genotype of DLG5 G113A was over represented in patients with CD or UC compared with that in controls [OR, 4.72:95% CI 2.30-9.66; P = 0.0001]. However, there were no significant associations found between all other polymorphisms studied and the susceptibility of CD or UC found in the Saudi population

Conclusion: Our finding indicates that association of IBD with nine gene polymorphisms was only significant in two of these polymorphic variants

Influence of vitamin D levels on bone mineral density and osteoporosis

The effects of vitamin D on bone mass remain to be understood. This study was conducted with the objective of evaluating the influence of 25-hydroxyvitamin D [25OHD] levels on bone mineral density [BMD] among Saudi nationals. Cross-sectional study carried out at university hospital from 1 February 2008 to 31 May 2008. Healthy Saudi men and women in the peak bone mass [PBM] age group and those aged >50 years were recruited from the outpatient department of King Fahd University Hospital, Al Khobar, Saudi Arabia, between February 1, 2008, and May 31, 2008. Patient age and sex were documented, and body mass index was calculated. Hematological, biochemical, and serum 25OHD tests were performed. BMD was determined by dual-energy x-ray absorptiometry of the upper femur and lumbar spine. Patients were divided into three groups, based on their 25OHD level. Data from 400 patients were analyzed. Among individuals with a normal 25OHD level, 50% of women and 7% of men in the PBM age group and 26.4% of women and 49.2% of men aged >50 years had low bone mass. In patients with 25OHD insufficiency, 84.2% of women and 88.9% of men in the PBM age group and 83.3% of women and 80% of men aged >50 years had low bone mass. Results for patients with 25OHD deficiency revealed that none of the men and women in the PBM age group or >50 years old had normal BMD. Significant positive correlations between 25OHD level and BMD and significant negative correlations with parathyroid hormone were shown in most of the groups. This study showed that the vitamin D level significantly influences BMD reading among Saudi individuals. Evaluation and treatment of hypovitaminosis D should be considered during management of low bone mass

there a relationship between body mass index and serum vitamin D levels?

To evaluate the relationship between vitamin D level and body mass index [BMI] among Saudi Arabian citizens. Four hundred healthy individuals aged >/= 25 years [200 males and 200 females] were included in this cross-sectional study. Subjects were recruited in the period between 1st February 2008 and 31st May 2008 from the medical staff and employees of King Fahd Hospital of the University, Al-Khobar, Kingdom of Saudi Arabia, and from patients attending the endocrinology, orthopedic, and infertility clinics at the same hospital. Clinical evaluation was carried out, and BMI was calculated. Serum 25 hydroxy vitamin D [25OHD], in addition to serum parathyroid hormone levels and calcium chemistry were measured for all subjects. The mean age was 46.5 +/- 14.6 years for males, and 42.6 +/- 15.9 years for females [p=0.01]. Mean BMI was similar in both genders, and the difference in the level of serum 25OHD just reached statistical significance [p=0.04]. Male subjects with vitamin D deficiency were found to be older [p=0.03], and with higher BMI [p=0.01] compared to males with normal 25OHD. Although female subjects with hypovitaminosis D were also older than subjects with normal vitamin D level [p=0.01], BMI was significantly lower in females with vitamin D deficiency [p=0.001]. Obese males are at higher risk of having low 25OHD levels, while obesity in females appears to be protective against vitamin D deficiency in the population studied. We believe that obese male and thin female patients should be appropriately investigated, and treated for vitamin D deficiency

25-Hydroxyvitamin D levels among healthy Saudi Arabian women

To assess the serum level of 25 hydroxyvitamin D 25OHD among healthy Saudi Arabian women living in the eastern province. A cross-sectional randomized study was conducted between February 1st 2008 and May 31st 2008 at the King Fahd University Hospital, Al-Khobar, Kingdom of Saudi Arabia in 200 Saudi women between 25-35 years group 1 and women of >/= 50 years group 2. Clinical examination, laboratory tests, a complete blood picture, serum calcium, phosphorous, alkaline phosphatase, parathormone, and the serum levels of 25OHD levels were carried out. Data on lifestyle, dietary, and demographic questionnaires were collected. Vitamin D was defined as deficient with serum level < 50 nmol/L, insufficient between 52-72 nmol/L, and normal as 75nmol/L. In group 1, 70% of women had normal 25OHD, and in women of group 2, 45% had normal levels of 25OHD. Alkaline phosphatase and parathormone levels were significantly higher in women with low vitamin D levels. Sun exposure and consumption of dairy products were minimal. Vitamin D deficiency among healthy young Saudi women of 25-35 years was 30% and 55% in women of >/= 50 years. This study indicates that hypovitaminosis D is common in young and postmenopausal women. Efforts are require to augment and encouraged women for adequate exposure to sunlight and increased intake of fortified vitamin D products to maintain skeletal health

Frequency of methylenetetrahydrofolate reductase C677T polymorphism in patients with cardiovascular disease in Eastern Saudi Arabia

Homozygosity for the C677T mutation in the gene of the thermolabile enzyme 5, 10 methylenetetrahydrofolate reductase [MTHFR] associates with reduced enzyme activity, leading to mild hyperhomocysteinemia. We now know that an elevated level of homocysteine is an important risk factor for cardiovascular disease [CVD]. The objective of this study was to determine the prevalence of the C677T mutation in Saudi patients diagnosed with CVD. Over a period of 2 years [2003-2004] in a case control study, we determined the prevalence of the C677T mutation in 83 CVD patients and in 40 age and gender-matched controls in the Eastern Province of Saudi Arabia. We determined the MTHFR genotype by restriction fragment length polymorphism and allele specific hybridization procedures. The CVD group showed over representation of the C677T allele frequencies [20.5%] compared with unaffected controls [15%] [p=0.3]. Furthermore, the genotypic data indicated that the prevalence of homozygosity for the C677T mutation was dramatically higher in the CVD patients [10.8%] when compared with normal [0%] [p=0.058]. These results suggest that the MTHFR C677T variant mildly influences CVD. However, we require further investigation in large independent samples