Body Fat Percentage and Blood Donation are the Strongest Determinants of Iron Stores in Premenopausal Women Joining the New Zealand Army.

INTRODUCTION: Suboptimal iron status is an issue for women joining the military because of its association with impaired aerobic performance, yet no studies have investigated dietary and non-dietary determinants of iron status simultaneously in this population. The purpose of this study was to explore associations between iron stores, dietary patterns (DPs), and potential non-dietary determinants of iron status in premenopausal women at the commencement of basic military training (BMT) in the New Zealand Army. METHODS: During week 1 of BMT, demographic, body composition, lifestyle, medical history, and dietary data were measured as potential determinants of serum ferritin (SF) in 101 participants. Following univariate analysis, age, body fat percentage, previous blood donation, at least 6 h of exercise per week that raised the heart rate, and a vegetarian DP were analyzed using a multiple linear regression model. RESULTS: An increase in body fat percentage was associated with increased SF (P < .009), although blood donation in the past year decreased SF (P < .011) compared to those participants who did not donate blood. There was no association between SF and a vegetarian DP or hours of exercise per week. The model explained 17.5% of the variance in SF at the commencement of BMT. CONCLUSION: Body fat percentage and blood donation in the past year were the strongest determinants of iron stores in healthy premenopausal women commencing BMT. It is recommended that women joining the New Zealand Army are provided information to maintain or improve their iron status based on these findings. This includes clinical screening of iron status, advice for women considering blood donation, and dietary advice regarding total energy requirements and iron bioavailability.

Iron status and associations with physical performance during basic combat training in female New Zealand Army recruits.

Decreases in Fe status have been reported in military women during initial training periods of 8-10 weeks. The present study aimed to characterise Fe status and associations with physical performance in female New Zealand Army recruits during a 16-week basic combat training (BCT) course. Fe status indicators - Hb, serum ferritin (sFer), soluble transferrin receptor (sTfR), transferrin saturation (TS) and erythrocyte distribution width (RDW) - were assessed at the beginning (baseline) and end of BCT in seventy-six volunteers without Fe-deficiency non-anaemia (sFer 10 mg/l at baseline or end. A timed 2·4 km run followed by maximum press-ups were performed at baseline and midpoint (week 8) to assess physical performance. Changes in Fe status were investigated using paired t tests and associations between Fe status and physical performance evaluated using Pearson correlation coefficients. sFer (56·6 (sd 33·7) v. 38·4 (sd 23·8) µg/l) and TS (38·8 (sd 13·9) v. 34·4 (sd 11·5) %) decreased (P<0·001 and P=0·014, respectively), while sTfR (1·21 (sd 0·27) v. 1·39 (sd 0·35) mg/l) and RDW (12·8 (sd 0·6) v. 13·2 (sd 0·7) %) increased (P<0·001) from baseline to end. Hb (140·6 (sd 7·5) v. 142·9 (sd 7·9) g/l) increased (P=0·009) during BCT. At end, sTfR was positively (r 0·29, P=0·012) and TS inversely associated (r -0·32, P=0·005) with midpoint run time. There were no significant correlations between Fe status and press-ups. Storage and functional Fe parameters indicated a decline in Fe status in female recruits during BCT. Correlations between tissue-Fe indicators and run times suggest impaired aerobic fitness. Optimal Fe status appears paramount for enabling success in female recruits during military training.

Peripheral arterial disease: the evolving role of non-invasive imaging.

Peripheral arterial disease is usually secondary to stenotic or occlusive atherosclerosis and is both common and increasing in western society. The majority of symptomatic patients have intermittent claudication and only a minority (<2% and typically those with diabetes mellitus or renal failure) progress to critical limb ischaemia, heralded by the onset of rest pain and/or tissue loss. Imaging is largely reserved for patients with disabling symptoms in whom revascularisation is planned. In these patients, accurate depiction of the vascular anatomy is critical for clinical decision making as the distribution and severity of disease are key factors determining whether revascularisation should be by endovascular techniques or open surgery. Driven by advances in technology, non-invasive vascular imaging has recently undergone significant refinement and has replaced conventional digital subtraction angiography for many clinical indications. In this review, the relative merits and limitations of duplex ultrasound, CT angiography, and magnetic resonance angiography are discussed, emerging imaging techniques are described, and complications relating to the use of intravascular contrast agents are highlighted.

The transjugular intrahepatic portosystemic shunt (TIPS).

The creation of an intrahepatic portosystemic shunt via a transjugular approach (TIPS) is an interventional radiological procedure used to treat the complications of portal hypertension. TIPS insertion is principally indicated to prevent or arrest variceal bleeding when medical or endoscopic treatments fail, and in the management refractory ascites. This review discusses the development and execution of the technique, with focus on its clinical efficacy. Patient selection, imaging surveillance, revision techniques, and complications are also discussed.

Diagnosis of suspected venous thromboembolic disease in pregnancy.

Venous thromboembolic disease is a leading cause of maternal mortality during pregnancy. Early and accurate radiological diagnosis is essential as anticoagulation is not without risk and clinical diagnosis is unreliable. Although the disorder is potentially treatable, unnecessary treatment should be avoided. Most of the diagnostic imaging techniques involve ionizing radiation which exposes both the mother and fetus to finite radiation risks. There is a relative lack of evidence in the literature to guide clinicians and radiologists on the most appropriate method of assessing this group of patients. This article will review the role of imaging of suspected venous thromboembolic disease in pregnant patients, highlight contentious issues such as radiation risk, intravenous contrast use in pregnancy and discuss the published guidelines, as well as suggesting an appropriate imaging algorithm based on the available evidence.

Myocardial revascularisation by laser.

Myocardial revascularisation by laser is an emerging treatment for refractory angina in patients with coronary artery disease that is not amenable to conventional revascularisation. With the original technique, laser energy was applied to epicardial surface of the heart through a lateral thoracotomy; so-called transmyocardial laser revascularisation (TMR). It is now possible, using catheter-based percutaneous myocardial revascularisation (PMR) to deliver laser energy to the myocardium via the endocardial surface. In this article we discuss the possible mechanism of action of laser revascularisation, and summarise the results of recent randomised controlled trials of TMR, PMR systems are described, and the growing evidence for their efficacy is reviewed.

The Collaborative Lipid Research Clinics Program Family Study. III. Transformations and covariate adjustments of lipid and lipoprotein levels.

Several methods of transformation and covariate adjustment have been applied to the Collaborative Lipid Research Clinics Program Family Study data to facilitate analysis of lipid levels of examinees of different sex and age groups. After several exploratory analyses, cholesterol, high density lipoprotein cholesterol, and low density lipoprotein cholesterol were logarithmically transformed, and triglycerides were transformed by the power -0.25. Two types of covariate adjustment procedures, the regression and Z score methods, were used. A modified regression method was developed and was found to be preferable to both simple cubic regression and the Z score method on theoretical and empirical grounds. Refinements in this method to correct for change in variance with age, and for the effect of socioeconomic status, seasonality, and anthropometric measures were made. Methodological issues connected with the transformation and adjustment procedures are discussed.

The Collaborative Lipid Research Clinics Program Family Study. IV. Familial associations of plasma lipids and lipoproteins.

Familial associations of total cholesterol, low density lipoprotein cholesterol, triglycerides, and very low density lipoprotein cholesterol were examined in a population-based random sample of 858 white and 73 black probands and their 4,027 white and 245 black relatives from nine North American Lipid Research Clinics. Correlations among biologic relatives were highly significant for total cholesterol and low density lipoprotein cholesterol and to a lesser extent for triglycerides and very low density lipoprotein cholesterol in whites. Correlations for spouses, however, were not significant, suggesting a stronger influence of genes than shared environment in the determination of these traits. Homogeneity of familial correlations across age strata, clinics, and racial groups was examined. In general, correlations were homogeneous across age strata and clinics, and there was no asymmetry in parent-offspring correlations by the sex of the parent or offspring. Racial differences in correlations were not significant except in four of 32 comparisons, with blacks showing weaker correlations than whites in those instances.

The Collaborative Lipid Research Clinics Program Family Study: detection of major genes influencing lipid levels by examination of heterogeneity of familial variances.

Age, sex-adjusted, and transformed lipid and lipoprotein data on over 1,200 white North American sibships in the Collaborative Lipid Research Clinics Family Study were analyzed for possible major genes causing high or low levels of these traits. The sibships were stratified on the basis of parents' trait values, and within-sibship variance in the high (or low) families was compared to that in the normal families via an F-test. The null hypothesis of multifactorial transmission was strongly rejected for low LDL, low total cholesterol, and high HDL families. An analysis of spouse-pair variance gave similar results. This may reflect the presence of dominant genes for hyperalpha- and hypobetalipoproteinemia. There was weaker evidence for single genes causing hyperbetalipoproteinemia. There was no evidence for major genes influencing triglyceride levels. Methodological issues with significant bearing on these results and those of other studies are discussed.

The inheritance of sinking-pre-beta lipoprotein and its relation to the Lp(a) antigen.

We have investigated the genetics of plasma sinking-pre-beta lipoprotein (sp beta) as determined by the method of Breckenridge and Maguire, using several approaches: (i) a population study, (ii) a twin study and (iii) the use of family data. In addition, by the use of split samples, the sp beta level as determined by us was correlated with Lp(a) typing carried out in Oslo by Dr. Kåre Berg. Although the sp beta level is a continuous character, the results clearly showed it to be to a considerable extent under the control of the major autosomal gene pair constituted by the alleles Lpa and Lp, which mainly control the production of the Lp(a) antigen, Lpa being dominant. In our data the boundary between the LpLp and LpaLp genotypes appeared to fall between the sp beta 2 and 3 mg% levels, while that between LpaLp and LpaLpa was in the 15 mg% region. These boundaries, which were inferred from both typing and population statistics, received good confirmation from the family data. It appears that some 88% of the variation in sp beta level is directly ascribed to segregation of Lpa and Lp. On the basis of the twin study and other data, we conclude that the residual observed variation in sp beta is almost entirely ascribed to analytical error of determination and polygenic effects, the influence of environment being negligible. The heritability is close to 100%.