Reliability of anthropometric measurements in overweight and lean subjects: consequences for correlations between anthropometric and other variables

OBJECTIVE: To estimate the reliability of anthropometric measurements in overweight and lean subjects, and to examine the influence of this reliability on correlations to other variables, since low reliability leads to underestimation of correlations. DESIGN: Replicate measurements by two observers in 26 overweight and 25 lean subjects measured at two occasions. MEASUREMENTS: Sagittal abdominal diameter (SAD), waist circumference (waist), waist-to-hip ratio (W/H) and skinfold measurements. RESULTS: Intra-class correlation coefficients (ICCs) for SAD and waist were higher than for W/H (0.98 vs. 0.90, P<0.001, and 0.97 vs. 0.90, P = 0.001, respectively). For waist, the ICC was lower for overweight than for lean subjects (0.85 vs 0.95, P=0.030), but the ICC values were comparable for SAD and W/H (0.92 vs. 0.95 and 0.78 vs. 0.83, respectively). Intra-observer variations (IOV) for SAD and waist were lower than for W/H (coefficients of variation; 1.6%, 1.4% and 2.3%, respectively), as were intra-subject variations (ISV) (2.7%, 3.0% and 3.4%, respectively). ICC values ranged from 0.84 to 0.93 and were lower for overweight than for lean subjects for biceps, subscapular and umbilical skinfolds (P=0.031, P<0.001 and P=0.048, respectively). Coefficients of variations for skinfold measurements ranged between 7.3% and 16.0% for IOV and between 14.9% and 20.8% for ISV. CONCLUSIONS: The low ICC values imply that correlations can be underestimated in overweight groups. We propose that, because of their higher reliability, SAD and waist have a higher predictive capacity for cardiovascular risk than W/H. SAD is the only measurement with high reliability in both weight groups and its use is recommended.     

Low and high circulating cortisol levels predict mortality and cognitive dysfunction early after stroke

OBJECTIVE: Elevated cortisol levels are associated with confusion and poor outcome after stroke. Dehydroepiandrosterone sulphate (DS), the most abundant adrenal androgen may act as an anti-glucocorticoid. An altered regulation of these steroids may affect numerous brain functions, including neuronal survival. The purpose of this study was to investigate serum cortisol and DS levels and the cortisol/DS ratio early after stroke and relate our findings to the presence of disorientation and mortality. DESIGN: Patients with acute ischaemic stroke (n = 88, 56 men and 32 women) admitted to a stroke unit were investigated with repeated clinical assessments and scores for degree of confusion, extent of paresis and level of functioning. Serum cortisol (C) and DS were measured on day 1 and/or day 4. Data for 28-day and 1-year mortality are presented. A control group of 65 age-matched healthy individuals was used. Multivariate analyses of mortality rates in the different tertiles or sixtiles of serum cortisol were performed with logistic regression, adjusting for age, sex, diabetes and level of consciousness. RESULTS: There was no difference in serum cortisol levels on day 1 for stroke patients when compared with control group values. Initial cortisol levels were significantly higher in the patients with acute disorientation versus orientated patients (P < 0.05). Cortisol levels on day 1 were an independent predictor of 28-day mortality, and patients with low cortisol levels (<270 nmol L(-1)) and increased levels (>550 nmol L(-1)) both had an increased 1-year mortality. DS levels on day 1 were significantly elevated in stroke patients. CONCLUSION: Hypercortisolism is associated with cognitive dysfunction early after ischaemic stroke. High and low circulating cortisol levels are associated with increased mortality after stroke. DS levels were not associated with clinical outcome.     

Urinary free cortisol excretion shortly after ischaemic stroke

The cortisol axis and catecholamine excretion were studied in 20 patients within the first week after acute ischaemic stroke. Urine free cortisol and plasma cortisol levels after dexamethasone were significantly higher in stroke patients than in 80-year-old volunteers (n = 32; P = 0.03 and P = 0.003, respectively). Catecholamine excretion was found to be significantly correlated with urine cortisol concentration (r = 0.54, P less than 0.05) and limb paresis (r = 0.52, P less than 0.05). In a multiple regression analysis, urine cortisol values were shown to be positively associated with limb paresis (P = 0.003), disorientation (P = 0.03) and body temperature (P = 0.03). High cortisol excretion was associated with a poorer functional outcome in a discriminant analysis (P = 0.001). Thus acute ischaemic stroke is associated with an increased activity in the cortisol axis. This may have a number of negative effects on organ functioning, and is a predictor of a poorer functional outcome.     

Lipids, apolipoproteins and steroids in serum and in fluid from stimulated and non-stimulated human ovarian follicles

Steroid production depends on the cholesterol (CH) substrate supplied by circulating lipoproteins which are internalised in the cells by receptor-mediated mechanisms. Low density lipoproteins (LDL) stimulate progesterone production in vitro. However, studies on follicles indicate low levels of LDL in follicular fluid (FF1). In the present study FF1 was obtained by ultrasound-guided punctures just before ovulation from 17 women participating in an in vitro fertilization programme. Serum was obtained simultaneously. Follicular development was stimulated with hMG-HCG or clomiphene-hMG-hCG combinations. In another 8 women FF1 was collected in connection with surgery for sterilization. FF1 levels of CH, triglycerides (TG), phospholipids (PL), apolipoprotein A1 and B (apoA1; apoB), oestradiol and progesterone were assayed in both groups as were the corresponding serum levels in the stimulated patient group. The FF1 levels of apoA1, TG and PL were approximately half of the levels in HDL in normal serum in both groups. However, CH was slightly lower in the stimulated group. ApoB was not detectable in FF1. Oestradiol was similar in both groups while progesterone was much higher in the stimulated than in the non-stimulated cycles. FF1 levels of apoA1 correlated positively to CH and PL in both groups and to progesterone in the stimulated follicles, while the correlation was negative in the other group. The absence of apoB and the levels of CH, TG, PL and apoA11 indicate that high density lipoprotein (HDL), but not LDL is present in FF1.(ABSTRACT TRUNCATED AT 250 WORDS)     

False hyperphosphoremia in multiple myeloma. Interference of monoclonal immunoglobulin G with the determination of blood phosphorus level]

A case of pseudohyperphosphataemia detected in a male patient with multiple IgG myeloma is reported. Phosphataemia, measured by a technique without previous deproteinization, reached 5.66 mM before any treatment and varied with treatment-induced changes in monoclonal immunoglobulin levels. Conversely, normal phosphataemia levels were found in blood samples taken before and after treatment when serum was deproteinized. This pseudohyperphosphataemia resulted from an increase in optic density due to interference between monoclonal immunoglobulin and the molybdic reagent used to determine phosphataemia. A retrospective investigation yielded three similar cases: two in patients with myeloma and one in a patient with non-myelomatous monoclonal dysglobulinaemia. A brief prospective study showed that this phenomenon was relatively frequent, as it was found in 2 out of 9 patients with monoclonal immunoglobulin (IgG in all 9 cases). These data indicate that the finding of marked hyperphosphataemia in subjects with monoclonal dysglobulinaemia should always prompt a control assay performed on deproteinized blood.