ABSTRACT
AIMS: There is emerging evidence of a relationship between vitamin D insufficiency and glucose intolerance. The aim of this study was to determine whether low serum 25-hydroxyvitamin D in early pregnancy is associated with an increased risk of gestational diabetes mellitus. METHODS: This nested case-control study examined the association between serum 25-hydroxyvitamin D and risk of gestational diabetes within a cohort of pregnant women from March 2008 to December 2009, who had undergone antenatal screening between 15 and 18 weeks gestation and subsequent glucose tolerance testing. Cases were women diagnosed with gestational diabetes and each case was matched to up to two controls without gestational diabetes on age, race and date of blood collection. Serum 25-hydroxyvitamin D was measured from stored antenatal screening samples and compared between cases and controls. RESULTS: Of the 116 women with gestational diabetes and 219 control subjects studied, the average age was 34.3 years and 41% were of non-Caucasian race. Women with gestational diabetes had significantly lower serum 25-hydroxyvitamin D compared with control subjects (56.3 vs. 62.0 nmol/l, P = 0.018). After adjusting for gestational age and maternal weight, serum 25-hydroxyvitamin D below the top quartile (< 73.5 nmol/l) was associated with a twofold greater likelihood of gestational diabetes (adjusted odds ratio 2.21, 95% confidence interval 1.19-4.13). CONCLUSIONS: Lower vitamin D status in early pregnancy was associated with a significantly increased risk of subsequent gestational diabetes that was independent of race, age, season and maternal weight. This study suggests that vitamin D may influence glucose tolerance during pregnancy and provides support for studies of vitamin D as a potential intervention to prevent gestational diabetes.
Subject(s)
Diabetes, Gestational/blood , Vitamin D Deficiency/blood , Vitamin D/analogs & derivatives , Adult , Case-Control Studies , Cohort Studies , Diabetes, Gestational/prevention & control , Female , Glucose Tolerance Test , Humans , Pregnancy , Pregnancy Trimester, First , Risk Assessment , Risk Factors , Vitamin D/blood , Vitamin D/therapeutic use , Vitamin D Deficiency/complicationsABSTRACT
BACKGROUND AND PURPOSE: Our goal was to characterize the geometry of simple-lobed cerebral aneurysms and to find the absolute size of these lesions from angiographic tracings. METHODS: Measurements of angiographic neck width (N), dome height (H), dome diameter (D), and semi-axis height (S) were obtained from tracings of 87 simple-lobed lesions located at the basilar bifurcation (BB), middle cerebral (MCA), anterior communicating (AcomA), posterior communicating (PcomA), superior cerebellar (SCA), and posterior cerebral (PCA) arteries. The following ratios were analyzed as subgroups according to location and as a collective sample: dome diameter/dome height (D/H), dome height/neck width (H/N), dome diameter/neck width (D/N), and dome height/semi-axis height (H/S). Using the parent artery as a reference, aneurysm dimensions were normalized to absolute in vivo size. Estimations were validated using angiographic markers. RESULTS: For the entire sample, mean ratios were D/H = 1.11, D/N = 1.91, and H/N = 1.86. For the H/S ratio, the value was 1.98 for BB, MCA, and PcomA lesions and significantly smaller for the AcomA subgroup, at 1.52. The average sizes (in mm) for these dimensions were N = 3.4 for MCA, 3.0 for AcomA, 3.1 for PcomA, and 6.5 for BB; D = 6.1 for MCA, 5.9 for AcomA, 5.3 for PcomA, and 11.7 for BB; H = 5.6 for MCA, 5.0 for AcomA, 5.3 for PcomA, and 11.3 for BB. On average, BB aneurysms were twice as large as aneurysms at other locations. Good correlations were found between the scaled values for D and N, H and N, and H and D. CONCLUSION: These results have been used to characterize the typical simple-lobed aneurysm geometry and to provide a framework for the development of a method of assessment of treatment choice and outcome on the basis of lesion geometry.
