The effect of vitamin D supplementation on knee osteoarthritis, the VIDEO study: a randomised controlled trial.

OBJECTIVE: Epidemiological data suggest low serum 25-hydroxyvitamin D3 (25-OH-D3) levels are associated with radiological progression of knee osteoarthritis (OA). This study aimed to assess whether vitamin D supplementation can slow the rate of progression. METHOD: A 3-year, double-blind, randomised, placebo-controlled trial of 474 patients aged over 50 with radiographically evident knee OA comparing 800 IU cholecalciferol daily with placebo. Primary outcome was difference in rate of medial joint space narrowing (JSN). Secondary outcomes included lateral JSN, Kellgren & Lawrence grade, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain, function, stiffness and the Get up and Go test. RESULTS: Vitamin D supplementation increased 25-OH-D3 from an average of 20.7 (standard deviation (SD) 8.9) µg/L to 30.4 (SD 7.7) µg/L, compared to 20.7 (SD 8.1) µg/L and 20.3 (SD 8.1) µg/L in the placebo group. There was no significant difference in the rate of JSN over 3 years in the medial compartment of the index knee between the treatment group (average -0.01 mm/year) and placebo group (-0.08 mm/year), average difference 0.08 mm/year (95% confidence interval (CI) [-0.14-0.29], P = 0.49). No significant interaction was found between baseline vitamin D levels and treatment effect. There were no significant differences for any of the secondary outcome measures. CONCLUSION: Vitamin D supplementation did not slow the rate of JSN or lead to reduced pain, stiffness or functional loss over a 3-year period. On the basis of these findings we consider that vitamin D supplementation has no role in the management of knee OA.

Rivaroxaban in antiphospholipid syndrome (RAPS) protocol: a prospective, randomized controlled phase II/III clinical trial of rivaroxaban versus warfarin in patients with thrombotic antiphospholipid syndrome, with or without SLE.

INTRODUCTION: The current mainstay of the treatment of thrombotic antiphospholipid syndrome (APS) is long-term anticoagulation with vitamin K antagonists (VKAs) such as warfarin. Non-VKA oral anticoagulants (NOACs), which include rivaroxaban, have been shown to be effective and safe compared with warfarin for the treatment of venous thromboembolism (VTE) in major phase III prospective, randomized controlled trials (RCTs), but the results may not be directly generalizable to patients with APS. AIMS: The primary aim is to demonstrate, in patients with APS and previous VTE, with or without systemic lupus erythematosus (SLE), that the intensity of anticoagulation achieved with rivaroxaban is not inferior to that of warfarin. Secondary aims are to compare rates of recurrent thrombosis, bleeding and the quality of life in patients on rivaroxaban with those on warfarin. METHODS: Rivaroxaban in antiphospholipid syndrome (RAPS) is a phase II/III prospective non-inferiority RCT in which eligible patients with APS, with or without SLE, who are on warfarin, target international normalized ratio (INR) 2.5 for previous VTE, will be randomized either to continue warfarin (standard of care) or to switch to rivaroxaban. Intensity of anticoagulation will be assessed using thrombin generation (TG) testing, with the primary outcome the percentage change in endogenous thrombin potential (ETP) from randomization to day 42. Other TG parameters, markers of in vivo coagulation activation, prothrombin fragment 1.2, thrombin antithrombin complex and D-dimer, will also be assessed. DISCUSSION: If RAPS demonstrates i) that the anticoagulant effect of rivaroxaban is not inferior to that of warfarin and ii) the absence of any adverse effects that cause concern with regard to the use of rivaroxaban, this would provide sufficient supporting evidence to make rivaroxaban a standard of care for the treatment of APS patients with previous VTE, requiring a target INR of 2.5.

National audit of the use of surgery and radiological embolization after failed endoscopic haemostasis for non-variceal upper gastrointestinal bleeding.

BACKGROUND: Following non-variceal upper gastrointestinal bleeding (NVUGIB), 10-15 per cent of patients experience further bleeding. Although surgery has been the traditional salvage therapy, there is renewed interest in transcatheter arterial embolization (TAE). This study examined the use, clinical characteristics and outcomes of patients receiving salvage surgery or TAE after failed endoscopic haemostasis for NVUGIB. METHODS: A UK national audit of upper gastrointestinal bleeding was undertaken in May and June 2007. A logistic regression model was used to identify clinical predictors of endoscopic failure. RESULTS: Data were analysed from 4478 patients involving 212 UK centres. Some 533 (11·9 per cent) experienced further bleeding, of whom 163 (30·6 per cent) proceeded to salvage therapy with surgery (97), TAE (60) or both (6). Among surgical patients (mean age 71 years), 66·0 per cent (68 of 103) had a Rockall score of at least 3 and emergency surgery was carried out between midnight and 08.00 hours in 21 per cent, with a consultant surgeon present in 89 per cent of operations. Some 9 per cent of patients had further bleeding after TAE, resulting in later surgery. The mortality rate was 29 per cent after surgery, 10 per cent after TAE and 23·2 per cent among those with further bleeding after the index endoscopy that was managed by endoscopy alone. The strongest predictors of endoscopic failure were coagulopathy (odds ratio 3·27, 95 per cent confidence interval 2·37 to 4·53) and a haemoglobin level of 10 g/dl or less (odds ratio 2·22, 1·71 to 2·87, for haemoglobin 8-10 g/dl). CONCLUSION: Salvage surgery and embolization are required in fewer than 4 per cent of patients with NVUGIB. The high postoperative mortality rate, reflecting age, co-morbidity and severity of bleeding, warrants a prospective study to establish the effectiveness and safety of TAE as an alternative to surgery in the management of bleeding after failure of endoscopic therapy.

Outcomes following acute nonvariceal upper gastrointestinal bleeding in relation to time to endoscopy: results from a nationwide study.

BACKGROUND AND STUDY AIMS: Despite the established efficacy of therapeutic endoscopy, the optimum timeframe for performing endoscopy in patients with nonvariceal upper gastrointestinal bleeding (NVUGIB) remains unclear. The aim of the current audit study was to examine the relationship between time to endoscopy and clinical outcomes in patients presenting with NVUGIB. PATIENTS AND METHODS: This study was a prospective national audit performed in 212 UK hospitals. Regression models examined the relationship between time to endoscopy and mortality, rebleeding, need for surgery, and length of hospital stay. RESULTS: In 4478 patients, earlier endoscopy ( < 12 hours) was not associated with a lower mortality or need for surgery compared with later ( > 24 hours) endoscopy (odds ratio [OR] for mortality 0.98, 95 % confidence interval [CI] 0.88 - 1.09 for endoscopy > 24 hours vs. < 12 hours; P = 0.70). In patients receiving therapeutic endoscopy, there was a nonsignificant trend towards an increase in rebleeding associated with later endoscopy (OR 1.13, 95 %CI 0.97 - 1.32 for endoscopy > 24 hours vs. < 12 hours), with the converse seen in patients not requiring therapeutic endoscopy (OR 0.83, 95 %CI 0.73 - 0.95 for endoscopy > 24 hours vs. < 12 hours; interaction P = 0.003). Later endoscopy ( > 24 hours) was associated with an increase in risk-adjusted length of hospital stay (1.7 days longer, 95 %CI 1.39 - 1.99 vs. < 12 hours; P < 0.001). CONCLUSIONS: Earlier endoscopy was not associated with a reduction in mortality or need for surgery. However, it was associated with an increased efficiency of care and potentially improved control of hemorrhage in higher risk patients, supporting the routine use of early endoscopy unless specific contraindications exist. These results may help inform the debate about emergency endoscopy service provision.

Patients' views on an education booklet following spinal surgery.

PURPOSE: This study evaluated an evidence-based education booklet developed for patients undergoing spinal surgery which was used as a treatment intervention in a multi-centre, factorial, randomised controlled trial (FASTER: Function after spinal treatment, exercise and rehabilitation) investigating the post-operative management of spinal surgery patients. This study sought to determine the acceptability and content of the booklet to patients. METHODS: Patients receiving the educational booklet before discharge from hospital as part of the FASTER study were asked to complete an evaluation, which rated the booklet "Your Back Operation" with regard to content, information, usability, etc. using forced and open questions. This assessment was conducted at the same time as the initial 6-week post-operative review performed as part of the larger study. RESULTS: Therefore, 97% of the 117 trial participants who returned their 6-week evaluation and randomised to receive a booklet returned their questionnaire. The booklet was highly rated receiving an overall rating of 7 or more out of 10 from 101/111 (91%), and high ratings for content, readability and information. The booklet's key messages were clear to the majority of patients; however, many patients highlighted deficiencies with respect to content particularly in relation to wound care and exercise. CONCLUSIONS: Patients valued the booklet and rated its content highly. Many suggested that the booklet be developed further and there was a clear desire for specific exercises to be included even though there is no evidence to support specific exercise prescription.

A randomised controlled trial of subcutaneous sodium salicylate therapy for osteoarthritis of the thumb.

BACKGROUND: Current treatment for osteoarthritis (OA) is limited. Many patients with OA of the hand have areas of tender subcutaneous thickening in the forearm and upper scapular region. A pilot study showed an improvement in pain from OA at the first carpometacarpal joint after injection of such areas with 0.5% sodium salicylate or saline, an inexpensive treatment that can be administered by general practitioners and nurses. The study indicated that a randomised, sham-controlled trial was justified. METHODS: 40 patients with OA of the first carpometacarpal joint were randomised to receive either injections of sodium salicylate into tender, thickened areas of subcutaneous tissue on the forearm (baseline) and upper scapular region (week 1) or sham injections consisting of pressure without skin penetration. Blinded assessments were made at weeks 3, 7 and 13 after baseline. RESULTS: Pain and tenderness during follow-up were both significantly lower in the active treatment group compared with the sham group: 19% and 14% greater reduction in mean visual analogue scale (VAS) score, respectively (p=0.007 and 0.02, baseline mean 5.65 and 5.35 cm, average difference in change from baseline VAS 1.9 and 1.4 cm, 95% CI 0.6 to 3.2 and 0.2 to 2.5). Active and sham injections were painful, the former significantly more so; however, there was no significant correlation between the pain of active injections and response. CONCLUSION: The data show that subcutaneous sodium salicylate injections are an effective symptomatic treatment for OA of the thumb. The results provide a basis for further physiological and therapeutic research in this area.

Function after spinal treatment, exercise and rehabilitation (FASTER): improving the functional outcome of spinal surgery.

BACKGROUND: The life-time incidence of low back pain is high and diagnoses of spinal stenosis and disc prolapse are increasing. Consequently, there is a steady rise in surgical interventions for these conditions. Current evidence suggests that while the success of surgery is incomplete, it is superior to conservative interventions. A recent survey indicates that there are large differences in the type and intensity of rehabilitation, if any, provided after spinal surgery as well as in the restrictions and advice given to patients in the post-operative period. This trial will test the hypothesis that functional outcome following two common spinal operations can be improved by a programme of post-operative rehabilitation that combines professional support and advice with graded active exercise and/or an educational booklet based on evidence-based messages and advice. METHODS/DESIGN: The study design is a multi-centre, factorial, randomised controlled trial with patients stratified by surgeon and operative procedure. The trial will compare the effectiveness and cost-effectiveness of a rehabilitation programme and an education booklet for the postoperative management of patients undergoing discectomy or lateral nerve root decompression, each compared with "usual care"using a 2 x 2 factorial design. The trial will create 4 sub-groups; rehabilitation-only, booklet-only, rehabilitation-plus-booklet, and usual care only. The trial aims to recruit 344 patients, which equates to 86 patients in each of the four sub-groups. All patients will be assessed for functional ability (through the Oswestry Disability Index - a disease specific functional questionnaire), pain (using visual analogue scales), and satisfaction pre-operatively and then at 6 weeks, 3, 6 and 9 months and 1 year post-operatively. This will be complemented by a formal analysis of cost-effectiveness. DISCUSSION: This trial will determine whether the outcome of spinal surgery can be enhanced by either a post-operative rehabilitation programme or an evidence-based advice booklet or a combination of the two and as such will contribute to our knowledge on how to manage spinal surgery patients in the post-operative period.

Risk factors and recommendations for rate stratification for surveillance of neonatal healthcare-associated bloodstream infection.

Neonates are among the most vulnerable patient groups for healthcare-associated infection with multiple endogenous and exogenous risks. Interpretation of neonatal bloodstream infection (BSI) rates requires stratification for case-mix. We assessed 1367 consecutive admissions to a single neonatal unit over a 34-month period. Four intrinsic and seven extrinsic risks were evaluated using Poisson regression analyses both individually and in combination. Nine of the 11 evaluated risk factors were significantly associated with BSI on univariate analyses. The only significant independent risks were parenteral nutrition, whether administered centrally or peripherally [incidence rate ratio (IRR): 14.2; 95% confidence interval (CI): 8.8-22.9; P<0.001], and gestational age <26 weeks (IRR: 2.5; 95% CI: 1.7-3.8; P<0.001). The rate of BSI per 1000 patient-days was 40 times higher in infants with both of these than in infants with neither. If validated in other settings, stratification of neonatal BSI rate by two unambiguous risk factors, parenteral nutrition and birth gestational age <26 weeks, offers a simple method to make meaningful intra- and inter-hospital comparisons.

Investigation of relationship between reduced, oxidized, and protein-bound homocysteine and vascular endothelial function in healthy human subjects.

Previous studies investigating homocysteine and vascular disease have relied on total plasma homocysteine as the sole index of homocysteine status. We examined the dynamic relationship between vascular endothelial function and concentrations of total, protein-bound oxidized, free oxidized, and reduced homocysteine to identify the homocysteine form associated with endothelial dysfunction in humans. We investigated 14 healthy volunteers (10 men, 4 women). Brachial artery flow-mediated dilatation was measured at baseline and at 30, 60, 120, 240, and 360 minutes after oral (1) L-methionine (50 mg/kg), (2) L-homocysteine (5 mg/kg), and (3) placebo. Plasma concentrations of total, protein-bound oxidized, free oxidized, and reduced homocysteine were measured at each time point, and nitroglycerin-induced dilatation at was assessed at 0, 120, and 360 minutes. Flow-mediated dilatation fell, and concentrations of total, protein-bound oxidized, free oxidized, and reduced homocysteine increased after oral homocysteine and oral methionine (all P<0.05 for difference in time course compared with placebo). Flow-mediated dilatation showed a reciprocal relationship with reduced homocysteine during both homocysteine and methionine loading. In both loading studies, peak reduction in flow-mediated dilatation coincided with maximal reduced homocysteine concentrations. In contrast, there was no consistent relationship between flow-mediated dilatation and free oxidized homocysteine, protein-bound oxidized homocysteine, or related species. Nitroglycerin-induced dilatation was unchanged by oral homocysteine and oral methionine (P>0.10 compared with placebo). Reduced homocysteine is closely associated with endothelial dysfunction during oral methionine and oral homocysteine loading. Our observations support the hypothesis that reduced homocysteine is the deleterious form of homocysteine for vascular function in vivo and suggest a less important role for other homocysteine species.

Accelerated postnatal head growth follows preterm birth.

BACKGROUND: Poor growth after preterm birth, particularly poor head growth, is associated with impaired neurodevelopmental outcome. OBJECTIVE: To evaluate weight gain and head growth between birth and term in a contemporary cohort of preterm infants, taking into account breast milk intake and illness severity. METHODS: Subjects were inborn infants or=37 weeks postmenstrual age. Weight and head circumference (HC) were expressed as standard deviation score (SDS), growth between birth and discharge as SDS gain (SDSG), and illness severity and breast milk exposure as the number of days of level 1 (full) intensive care (%L1IC) and the number of days on which breast milk was received (%BM) as a percentage of days from birth to discharge. RESULTS: Infants showed poor postnatal weight gain but accelerated head growth. There was a highly significant fall in mean (SD) weight SDS between birth and discharge (-0.31 (0.96) and -1.32 (1.02) respectively, p<0.001) and a highly significant increase in HC SDS (-0.52 (0.95) and -0.03 (1.25) respectively, p = 0.003). %L1IC had a highly significant negative impact on weight SDSG (p = 0.006), and %BM had a significant positive impact on HC SDSG (p = 0.043). CONCLUSIONS: Accelerated postnatal head growth suggests catch up after antenatal restraint. This raises the possibility that poor neurocognitive outcomes after extremely preterm birth may in part be consequent on poor intrauterine brain growth. As postnatal head growth may be facilitated by breast milk, there is an urgent need to evaluate the optimal use of breast milk in preterm neonates. Illness severity is a significant determinant of poor postnatal weight gain.

A randomised controlled trial of flow driver and bubble continuous positive airway pressure in preterm infants in a resource-limited setting.

OBJECTIVES: The variable-flow flow driver (FD; EME) and continuous-flow bubble (Fisher-Paykel) continuous positive airway pressure (CPAP) systems are widely used. As these differ in cost and technical requirements, determining comparative efficacy is important particularly where resources are limited. DESIGN: We performed a randomised, controlled, equivalence trial of CPAP systems. We specified the margin of equivalence as 2 days. We analysed binary variables by logistical regression adjusted for gestation, and log transformed continuous variables by multiple linear regression adjusted for gestation, sex and antenatal steroids. SETTING: A neonatal unit with no blood gas analyser or surfactant availability and limited X-ray and laboratory facilities PATIENTS: Neonates <37 weeks of gestation. INTERVENTIONS: We provided CPAP at delivery followed by randomisation to FD or bubble (B). OUTCOMES: Primary outcome included total days receiving CPAP; secondary outcomes included days receiving CPAP, supplemental oxygen, ventilation, death, pneumothorax and nasal excoriation. RESULTS: We randomised 125 infants (B 66, FD 59). Differences in infant outcomes on B and FD were not statistically significant. The median (range) for CPAP days for survivors was B 0.8 (0.04 to 17.5), FD 0.5 (0.04 to 5.3). B:FD (95% CI) ratios were CPAP days 1.3 (0.9 to 2.1), CPAP plus supplementary oxygen days 1.2 (0.7 to 1.9). B:FD (95% CI) ORs were death 2.3 (0.2 to 28), ventilation 2.1 (0.5 to 9), nasal excoriation 1.2 (0.2 to 8) and pneumothorax 2.4 (0.2 to 26). CONCLUSIONS: In a resource-limited setting we found B CPAP equivalent to FD CPAP in the total number of days receiving CPAP within a margin of 2 days. TRIAL REGISTRATION NUMBER: ISRCTN22578364.

Factors associated with mortality in patients with asymptomatic carotid stenosis: results from the ACSRS Study.

AIM: This study determines the factors associated with mortality in patients with asymptomatic carotid stenosis. METHODS: Patients (n=1,101) with asymptomatic internal carotid artery stenosis greater than 50% in relation to the bulb diameter were followed up for a period of 6 to 84 (median 38) months. Stenosis was graded using duplex scanning and expressed as a percentage of the carotid bulb diameter. Clinical and biochemical risk factors were recorded. The end-points were ipsilateral ischemic stroke, cardiovascular death and all cause mortality. RESULTS: In a Cox multivariate analysis 6 factors emerged as independent predictors of risk. Age, male gender, cardiac failure, left ventricular hypertrophy on electrocardiogram (ECG) and myocardial ischemia on ECG were associated with increased risk. Antiplatelet therapy was associated with decreased risk. Based on these risk factors a high-risk group consisting of one third of the population with a 40% cumulative cardiovascular death rate and a 66% all cause death rate at 7 years could be identified. The remaining 2/3 consisted of a low-risk group with a 10% cumulative cardiovascular death rate and a 21% all cause death rate at 7 years (P<0.0001 compared to the high risk group). There was not any significant difference in the cumulative ipsilateral stroke rate, which was 12% in the low and 13% in the high cardiovascular risk group (Log Rank P>0.05). CONCLUSIONS: The methodology and findings from the ACSRS natural history study need to be applied to randomized controlled trials on the value of carotid endarterectomy or stenting in patients with asymptomatic carotid stenosis. They may help refine the indications for intervention in patients with carotid endarterectomy.

The effects of MK801 on the high pressure neurological syndrome in the baboon (Papio anubis).

The in vivo neurophysiological interactions of the non-competitive NMDA receptor antagonist MK801 with the High Pressure Neurological Syndrome have been investigated in the primate Papio anubis. A hyperbaric chamber was used to achieve environmental pressures of 61 ATA (atmospheres absolute) over a period of 5 hr. Eight animals underwent 2 compressions each, one following pretreatment with 0.03 mg/kg (i.v.) MK801, the other a control. Half of the animals received MK801 on their first exposure. Mild signs of the high pressure neurological syndrome, e.g. paw and limb tremor were first observed between 10 and 20 ATA and more severe signs, e.g. whole body tremor, myoclonus and vomiting, appeared after 50 ATA. The onset pressures for the various signs were increased by 10-17 ATA when the animals received MK801 (P = 0.06) and the severity of the signs, over the whole range of pressures at which they appeared, was significantly reduced (P less than 0.001). Additional experiments showed that MK801 afforded considerable protection, at pressures up to 81 ATA, but doses larger than those used for the main experiment produced signs of tranquilisation and sedation. Changes in the EEG were observed in channels associated with the frontal, parietal and occipital regions. Amplitude and frequency spectra were calculated and trends with pressure in the 4 conventional wavebands were analysed. The most striking change was a decrease in amplitude of delta waves (P less than 0.001), which was ameliorated by MK801 (P less than 0.001).

A randomized, controlled trial of prophylactic granulocyte-macrophage colony-stimulating factor in human newborns less than 32 weeks gestation.

OBJECTIVE: Preterm neonates undergoing intensive care have high morbidity from sepsis. These infants also frequently develop neutropenia, and when this is associated with sepsis, mortality is high. This study investigates the potential for granulocyte-macrophage colony-stimulating factor (GM-CSF) to effect a clinically relevant increase in neutrophil number when used prophylactically in high-risk preterm neonates, and assesses its safety in this population. DESIGN: In an open, randomized, controlled study, 75 neonates (25 small for gestational age) <32 weeks gestation were randomized to receive GM-CSF (10 microg/kg/d) by subcutaneous injection for 5 days from <72 hours after birth, or to a control group. The primary outcome measure was the neutrophil count during 14 days from study entry. The infants were monitored for potential toxicity. Clinical outcomes, sepsis, and mortality, were recorded, but this initial study was not designed to address clinical benefit. RESULTS: Prophylactic GM-CSF therapy completely abolished neutropenia in treated infants, when both well and septic, throughout the period of study. Neutropenia (

Comparison of diltiazem at two dose levels with propranolol for treatment of stable angina pectoris.

Two dose levels of diltiazem with propranolol were compared in the management of chronic stable angina. Two groups of patients were treated for alternate periods of 4 weeks with each drug in a double-blind crossover with computer-assisted maximal treadmill tests and ambulatory ST-segment monitoring for evaluation of efficacy and safety. In 12 patients who received diltiazem, 180 mg/day, the time to development of angina increased from 5.9 +/- 0.7 minutes (+/- standard error of the mean) during placebo treatment to 8.3 +/- 0.8 minutes during diltiazem treatment and to 9.2 +/- 0.8 minutes with propranolol, 240 mg/day. Three patients became angina-free when they were treated with both drugs. Among 12 patients who received diltiazem, 360 mg/day, 1 patient became angina-free during treatment with both drugs and 1 became angina-free with diltiazem only. The mean exercise time increased from 5.8 +/- 0.7 minutes with placebo to 8.6 +/- 1.0 minutes with diltiazem, 360 mg/day, and to 8.2 +/- 0.6 minutes with propranolol, 240 mg/day. Analysis of variance showed no difference in efficacy between the 2 doses of diltiazem or between the 2 drugs. Ambulatory heart rate was reduced both during the day and at night with both drugs and significantly more with propranolol than with diltiazem treatment. Except for 1 patient in whom a rash developed when given diltiazem, 180 mg/day, and another who had both a rash and first-degree heart block with diltiazem, 360 mg/day, both drugs were well tolerated. Thus, diltiazem in a daily dose of 180 or 360 mg/day is as effective as propranolol for the treatment of chronic stable angina.

EEG electrode positions outside the hairline to monitor sleep in man.

This study investigated the use of electroencephalographic (EEG) electrode placements outside the hairline to monitor sleep. Six subjects slept for 1 night during which the EEG was recorded from "standard" electrode placements and simultaneously from the "test" placements outside the hairline where adhesive pregelled electrodes could be used. Each subject's EEG record was scored independently by two observers. The standard and test electrode placements were assessed separately. Cohen's kappa (kappa) was used to quantify the agreement in the sleep scores (a) between observers when both scored the standard placements and (b) between the test and standard placements when scored by the same observer. The agreement for all stages between observers (a) was excellent (kappa = 0.82); and the agreement within observers, between placements (b) was even better [kappa = 0.86 for the six sleep stages considered separately; when stages awake/1 and 3/4 were combined (a) kappa = 0.88 and (b) kappa = 0.09]. It is concluded that EEG electrode placements outside the hairline can be used effectively to record sleep EEGs. The adoption of these electrode placements would simplify the monitoring procedure for many applied physiological studies especially when usual laboratory techniques for EEG are precluded.

Sensitivity and specificity of radioisotope right-left shunt measurements and pulse oximetry for the early detection of pulmonary arteriovenous malformations.

STUDY OBJECTIVES: To assess the effectiveness of pulse oximetry and radioisotope measurement of right-to-left (R-L) shunt for the early detection of pulmonary arteriovenous malformations (PAVMs) in patients with hereditary hemorrhagic telangiectasia (HHT). DESIGN: Patients with HHT had serial measurements of the following: (1) arterial oxygen saturation (SaO2) by pulse oximetry in erect and supine positions, and on maximal exercise using cycle ergometry; (2) quantitative radioisotope measurements of R-L shunt using IV 99mTc-labeled macroaggregates of albumin; and (3) routine pulmonary function. After percutaneous transcatheter embolization of all PAVMs with feeding vessel diameters > 3 mm, residual PAVMs were assessed with selective digital subtraction pulmonary angiography. Using postembolization angiography as the "gold standard," SaO2 and radioisotope shunt measurements after embolization were analyzed retrospectively using logistic regression to assess the ability of each test to predict for the presence of residual PAVMs. RESULTS: Of the 66 patients included, 40 had small PAVMs remaining postembolization. Using univariate logistic regression, radioisotope shunt and erect saturation showed a significant relationship with the presence of residual PAVMs (p=0.001, 0.005, respectively). Erect SaO2 < or = 96% had 73% sensitivity and 35% specificity for detecting PAVMs. Radioisotope shunt >3.5% of cardiac output had 87% sensitivity and 61% specificity for detecting PAVMs. CONCLUSIONS: These results confirm that noninvasive measurements are useful in the screening of patients with HHT for the presence of PAVMs without need for angiography and its associated risks, and that radionuclide scanning is better than pulse oximetry.

Ambulatory intraarterial blood pressure in essential hypertension. Effects of age, sex, race, and body mass--the Northwick Park Hospital Database Study.

Twenty-four-hour recordings of intraarterial blood pressure (IABP) from 723 untreated hypertensive patients were analyzed for the effects of age, sex, race, and body mass index on the level of IABP and its circadian variation. Age had a highly significant positive relationship (P < .001) with the cuff systolic and diastolic blood pressures, with regression coefficients (SE) of +0.83 (0.07) and -0.24 (0.04) mm Hg/year, respectively. There was a similar (P < .001) positive relationship between age and 24-h mean systolic IABP, measuring +0.71 (0.07) mm Hg/year, but 24-h mean diastolic IABP did not increase significantly with age. There was a significant (P < .001) inverse relationship between age and 24-h mean heart rate (HR), at -0.17 (0.03) beats/min/year. Nocturnal fall in systolic and diastolic IABP, calculated as the difference between daytime and nighttime mean IABP, had a significant (P < .001) negative relationship with age. Nocturnal fall in HR, calculated similarly, also significantly (P < .001) decreased with age. Age did not affect long-term systolic and diastolic IABP variability but did decrease long-term HR variability significantly (P < .001). Hypertensive men and women of similar age, had comparable daytime mean systolic and diastolic IABP (P = .15 and P = .03 respectively), but women had significantly (P < .001) lower nighttime mean systolic and diastolic IABP than men. The nocturnal fall in systolic and diastolic IABP was significantly (P < .002) greater in women as compared to men. Women also had significantly (P < .01) greater long-term systolic and diastolic IABP variability than men. Women had significantly (P < .001) greater 24-h, daytime mean and nighttime mean HR than men. Twenty-four-hour, daytime and nighttime mean IABP were all significantly higher (P < .01) in Afro-Caribbeans as compared to whites and Asians. No significant differences were observed in the magnitude of nocturnal IABP fall or long-term IABP variability between the three races. Asians and Afro-Caribbeans had significantly (P < .001) lower nocturnal HR falls and long-term HR variability (P < .01) than whites. Body mass index (BMI) did not relate directly to the level of daytime blood pressure, clinic cuff, or daytime mean IABP, in either men or women. BMI did have a highly significant (P < .001) positive relationship with nighttime mean IABP in men, but not in women. The degree of nocturnal fall of IABP had a significant (P < .001) inverse relationship with BMI in hypertensive men.

The effect of deprenyl, a selective monoamine oxidase B inhibitor, on sleep and mood in man.

The effect of (-)-deprenyl, a rapidly acting selective monoamine oxidase (MAO) B inhibitor, on the sleep and mood of six healthy young male adults was investigated. The drug was administered double-blind in a balanced cross-over design. The dose (5-10 mg/day for 3 days) was chosen to cause complete inhibition of MAO, a process which usually takes 1-2 weeks with conventional MAO inhibitors. The inhibition was monitored by measuring platelet MAO activity and phenylethylamine excretion. Urinary phenylethylamine concentration was raised in all subjects. Subjects were unaware of any sleep disturbance due to the drug although the electroencephalogram (EEG) showed increased wakefulness. The onset of rapid-eye-movement (REM) sleep was delayed and the total amount reduced; the amount of stage 2 sleep was increased. The only effect of the drug on mood was to decrease the level of alertness prior to sleep. There was a slight but significant increase in the pre-sleep systolic blood pressure. There were no effects due to drug withdrawal.

Variations in the virulence, for pregnant guinea pigs, of campylobacters isolated from man.

Pregnant guinea pigs were used to compare the virulence of four human isolates of Campylobacter fetus ss. fetus and four of C. jejuni on the basis of their ability to cause abortion and bacteraemia. Of the four strains of C. fetus ss. fetus two produced abortion readily after intramuscular injection. The four C. jejuni isolates were, however, of comparatively low virulence and no differences between them were demonstrated. Some of the isolates differed in their ability to survive in vitro in human and guinea-pig serum. It is suggested that campylobacters vary in their virulence for man and that this may influence the outcome of infections. Guinea pigs may prove useful in studying the pathogenesis of systemic campylobacter infections.