Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 203
Filter
1.
Ultrasound Obstet Gynecol ; 58(3): 494-495, 2021 09.
Article in English | MEDLINE | ID: mdl-34468058
2.
Ultrasound Obstet Gynecol ; 58(2): 329-330, 2021 08.
Article in English | MEDLINE | ID: mdl-34346120
3.
Ultrasound Obstet Gynecol ; 57(6): 925-930, 2021 06.
Article in English | MEDLINE | ID: mdl-33798274

ABSTRACT

OBJECTIVE: The recent international guidelines by the Society for Maternal-Fetal Medicine (SMFM) and the International Society of Ultrasound in Obstetrics and Gynecology (ISUOG) differ in their definitions of fetal growth restriction (FGR). Our aim was to compare the performance of the two definitions in predicting neonatal small-for-gestational age (SGA) and composite adverse neonatal outcome (ANO). METHODS: This was a secondary analysis of data from a prospective study of women referred for fetal growth ultrasound examination between 26 + 0 and 36 + 6 weeks' gestation. The SMFM and ISUOG guidelines were used to define pregnancies with FGR. The SMFM definition of FGR is estimated fetal weight (EFW) or abdominal circumference (AC) < 10th percentile. The ISUOG-FGR definition follows the Delphi consensus criteria and includes either EFW or AC < 3rd percentile or EFW or AC < 10th percentile combined with abnormal Doppler findings or a decrease in growth centiles. The primary outcome was the prediction of neonatal SGA, defined as birth weight < 10th percentile, and a composite of ANO, which was defined as one or more of: Grade-III or -IV intraventricular hemorrhage, respiratory distress syndrome, neonatal death, cord blood pH < 7.1, seizures and admission to the neonatal intensive care unit. Test characteristics (sensitivity, specificity, positive predictive value (PPV), negative predictive value and positive (LR+) and negative likelihood ratios) and area under the receiver-operating-characteristics curve were determined. The association between FGR detected by each definition and selected adverse outcomes was assessed using logistic regression analysis. RESULTS: Of the 1054 pregnancies that met the inclusion criteria, 137 (13.0%) and 55 (5.2%) were defined as having FGR by the SMFM and ISUOG definitions, respectively. Composite ANO and SGA neonate each occurred in 139 (13.2%) pregnancies. For the prediction of neonatal SGA, the SMFM-FGR definition had a higher sensitivity (54.7%) than did the ISUOG definition (28.8%). The ISUOG-FGR definition had higher specificity (98.4% vs 93.3%), LR+ (18.0 vs 8.2) and PPV (72.7% vs 55.5%) than did the SMFM definition for the prediction of a SGA neonate. The SMFM- and ISUOG-FGR definitions had similarly poor performance in predicting composite ANO, with sensitivities of 15.1% and 10.1%, respectively. CONCLUSIONS: The SMFM definition of FGR is associated with a higher detection rate for SGA neonates but at the cost of some reduction in specificity. The ISUOG-FGR definition has a higher specificity, LR+ and PPV for the prediction of neonatal SGA. Both definitions of FGR performed poorly in predicting a composite ANO. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.


Subject(s)
Fetal Growth Retardation/diagnosis , Infant, Small for Gestational Age , Practice Guidelines as Topic , Prenatal Diagnosis , Adult , Female , Fetal Weight , Gestational Age , Humans , Obstetrics , Pregnancy , Prospective Studies , Societies, Medical , Young Adult
4.
J Appl Psychol ; 105(3): 312-329, 2020 Mar.
Article in English | MEDLINE | ID: mdl-31328925

ABSTRACT

The multifaceted structure of multisource job performance ratings has been a subject of research and debate for over 30 years. However, progress in the field has been hampered by the confounding of effects relevant to the measurement design of multisource ratings and, as a consequence, the impact of ratee-, rater-, source-, and dimension-related effects on the reliability of multisource ratings remains unclear. In separate samples obtained from 2 different applications and measurement designs (N1 [ratees] = 392, N1 [raters] = 1,495; N2 [ratees] = 342, N2 [raters] = 2,636), we, for the first time, unconfounded all systematic effects commonly cited as being relevant to multisource ratings using a Bayesian generalizability theory approach. Our results suggest that the main contributors to the reliability of multisource ratings are source-related and general performance effects that are independent of dimension-related effects. In light of our findings, we discuss the interpretation and application of multisource ratings in organizational contexts. (PsycINFO Database Record (c) 2020 APA, all rights reserved).


Subject(s)
Employee Performance Appraisal/standards , Psychometrics/standards , Work Performance , Adult , Bayes Theorem , Humans , Reproducibility of Results
5.
Hum Exp Toxicol ; 38(2): 157-172, 2019 Feb.
Article in English | MEDLINE | ID: mdl-30062923

ABSTRACT

Inhalant abuse is a significant public health issue, particularly for adolescents, the predominant group of inhalant users. Adolescence is a critical growth period, and inhalant abuse has been associated with growth impairments, including reduced body weight and height. However, the extent to which inhalant abuse affects growth remains unquantified, and potential moderators remain unknown. To address this knowledge gap, a systematic review and meta-analysis of clinical human and preclinical animal studies utilizing toluene exposure (the primary solvent in abused products) was conducted. Five-hundred and sixty-nine studies were screened; 31 met inclusion criteria, yielding 64 toluene-control comparisons for body weight and 6 comparisons for height. Toluene exposure was negatively associated with body weight ( d = -0.73) and height ( d = -0.69). Concentration of inhaled toluene, but not duration, moderated the effect of toluene exposure on body weight, with more severe impairments at higher concentrations. Differences in effect size for body weight were observed for study characteristic subgroups including sex, age at first exposure, administration route and species. However, these findings should be interpreted cautiously due to low study numbers. Growth impairments, particularly during adolescence, can cause long-term health consequences. These effects on growth are therefore an important clinical outcome for individuals with a history of inhalant abuse.


Subject(s)
Inhalant Abuse/complications , Solvents/toxicity , Toluene/toxicity , Animals , Body Height/drug effects , Body Weight/drug effects , Humans
6.
J Appl Psychol ; 101(7): 976-94, 2016 Jul.
Article in English | MEDLINE | ID: mdl-26963079

ABSTRACT

Despite a substantial research literature on the influence of dimensions and exercises in assessment centers (ACs), the relative impact of these 2 sources of variance continues to raise uncertainties because of confounding. With confounded effects, it is not possible to establish the degree to which any 1 effect, including those related to exercises and dimensions, influences AC ratings. In the current study (N = 698) we used Bayesian generalizability theory to unconfound all of the possible effects contributing to variance in AC ratings. Our results show that ≤1.11% of the variance in AC ratings was directly attributable to behavioral dimensions, suggesting that dimension-related effects have no practical impact on the reliability of ACs. Even when taking aggregation level into consideration, effects related to general performance and exercises accounted for almost all of the reliable variance in AC ratings. The implications of these findings for recent dimension- and exercise-based perspectives on ACs are discussed. (PsycINFO Database Record


Subject(s)
Employee Performance Appraisal/standards , Personnel Selection/standards , Psychological Tests/standards , Psychometrics/standards , Female , Humans , Male , Middle Aged
7.
Br J Dermatol ; 175(4): 782-4, 2016 Oct.
Article in English | MEDLINE | ID: mdl-26875995

ABSTRACT

Graft-versus-host disease-associated angiomatosis (GVHD-AA) is an uncommon manifestation of chronic GVHD consisting of friable vascular proliferations. Using fluorescence in situ hybridization, we demonstrate the presence of donor-derived endothelial cells within areas of GVHD-AA. This is the first documented occurrence of a benign neoplastic growth in relationship to a form of chronic GVHD.


Subject(s)
Angiomatosis/etiology , Graft vs Host Disease/etiology , Hematopoietic Stem Cell Transplantation/adverse effects , Scleroderma, Systemic/etiology , Transplantation Chimera , Chimera , Chronic Disease , Endothelial Cells , Female , Humans , Sex Chromosomes , Transplantation, Homologous
8.
Br J Pharmacol ; 172(21): 5174-87, 2015 Nov.
Article in English | MEDLINE | ID: mdl-26282596

ABSTRACT

BACKGROUND AND PURPOSE: Abuse of toluene-containing inhalants is an increasing public health problem, especially among adolescents. Abuse during adolescence is associated with emaciation, while industrial exposure leads to altered glycaemic control suggesting metabolic instability. However, the relationship between adolescent inhalant abuse and metabolic dysfunction remains unknown. EXPERIMENTAL APPROACH: To model human abuse patterns, we exposed male adolescent Wistar rats [postnatal day (PND) 27] to chronic intermittent inhaled toluene (CIT, 10,000 ppm) or air (control) for 1 h·day(-1) , three times a week for 4 weeks. Feeding and body composition were monitored. After 4 weeks, circulating metabolic hormone concentrations and responses to a glucose tolerance test (GTT) were measured. Dietary preference was measured by giving animals access to either a 'western diet' plus standard chow (WC + SC) or standard chow alone during 4 weeks of abstinence. Metabolic hormones and GTT were subsequently measured. KEY RESULTS: Adolescent CIT exposure significantly retarded weight gain, altered body composition, circulating metabolic hormones and responses to a GTT. While reduced body weight persisted, responses to a GTT and circulating hormones appeared to normalize for animals on standard chow following abstinence. In CIT-exposed WC + SC rats, we observed impaired glucose tolerance associated with altered metabolic hormones. Analysis of hypothalamic genes revealed differential expression profiles in CIT-exposed rats following both the exposure period and abstinence, suggesting a central contribution to inhalant-induced metabolic dysfunction. CONCLUSION AND IMPLICATIONS: CIT exposure during adolescence has long-term effects on metabolic function, which may increase the risk of disorders related to energy balance and glycaemic control.


Subject(s)
Glucose/metabolism , Homeostasis , Metabolic Diseases/chemically induced , Toluene/toxicity , Administration, Inhalation , Animals , Male , Rats , Rats, Wistar , Toluene/administration & dosage
9.
Water Sci Technol ; 63(1): 149-55, 2011.
Article in English | MEDLINE | ID: mdl-21245567

ABSTRACT

The process of platinum group metal (PGM) refining can be up to 99.99% efficient at best, and although it may seem small, the amount of valuable metal lost to waste streams is appreciable enough to warrant recovery. The method currently used to remove entrained metal ions from refinery wastewaters, chemical precipitation, is not effective for selective recovery of PGMs. The yeast Saccharomyces cerevisiae has been found capable of sorbing numerous precious and base metals, and is a cheap and abundant source of biomass. In this investigation, S. cerevisiae was immobilised using polyethyleneimine and glutaraldehyde to produce a suitable sorbent, capable of high platinum uptake (150-170 mg/g) at low pH (<2). The sorption mechanism was found to be a chemical reaction, which made effective desorption impossible. When applied to PGM refinery wastewater, two key wastewater characteristics limited the success of the sorption process; high inorganic ion content and complex speciation of the platinum ions. The results proved the concept principle of platinum recovery by immobilised yeast biosorption and indicated that a more detailed understanding of the platinum speciation within the wastewater is required before biosorption can be applied. Overall, the sorption of platinum by the S. cerevisiae sorbent was demonstrated to be highly effective in principle, but the complexity of the wastewater requires that pretreatment steps be taken before the successful application of this process to industrial wastewater.


Subject(s)
Platinum/metabolism , Saccharomyces cerevisiae/metabolism , Water Pollutants, Chemical/metabolism
10.
Biotechnol Adv ; 25(3): 264-71, 2007.
Article in English | MEDLINE | ID: mdl-17293076

ABSTRACT

Biosorption has emerged as a low-cost and often low-tech option for removal or recovery of base metals from aqueous wastes. The conditions under which precious metals such as gold, platinum and palladium are sorbed by biomass are often very different to those under which base metals are sorbed. This, coupled with the increasingly high demand for precious metals, drives the increase in research into efficient recovery of precious metal ions from all waste material, especially refining wastewaters. Common biosorbents for precious metal ions include various derivatives of chitosan, as well as other compounds with relatively high surface amine functional group content. This is generally due to the ability of the positively charged amine groups to attract anionic precious metal ions at low pH. Recent research regarding the biosorption of some precious metals is reviewed here, with emphasis on the effects of the biosorption environment and the biosorption mechanisms identified.


Subject(s)
Biomass , Metals/chemistry , Metals/isolation & purification , Waste Disposal, Fluid/methods , Adsorption , Environment , Sewage/chemistry
11.
Eur J Surg Oncol ; 33(6): 706-12, 2007 Aug.
Article in English | MEDLINE | ID: mdl-17207958

ABSTRACT

AIMS: To assess the effect of previous peptic ulcer surgery on subsequent malignant events, in particular in relation to previous vagotomy, a historical cohort study was conducted. METHODS: All patients undergoing surgery for peptic ulcer disease with accurate follow-up data at a large peptic ulcer clinic in the Western Infirmary, Glasgow, from 1965 to 1983 were assessed. All cancer events and specific cancer events (gastric, bronchial, laryngeal, colorectal, bladder, breast, prostate, pancreas, kidney, oesophageal cancers) were determined as outcome measures and expressed as standardised incidence ratio (SIR). RESULTS: Vagotomy and drainage accounted for 67% of all procedures for peptic ulcer disease. Eighty-three percent were habitual smokers. For all peptic ulcer surgery patients, the SIR for all cancer events was 0.86. For specific cancers, the SIRs were bronchial cancer (SIR 1.13); laryngeal cancer (SIR 2.17), colorectal cancer (SIR 0.67). For vagotomised patients the risk of gastric cancer was significantly elevated (SIR 1.50). CONCLUSIONS: An excess of cancers attributable to smoking have been found in peptic ulcer surgery patients. Vagotomised patients have a higher risk of gastric cancer after long term follow-up. This finding may have implications for screening and the safety of long term acid suppression with agents such as proton pump inhibitors.


Subject(s)
Neoplasms/epidemiology , Peptic Ulcer/surgery , Vagotomy/statistics & numerical data , Bronchial Neoplasms/epidemiology , Cohort Studies , Colonic Neoplasms/epidemiology , Drainage/statistics & numerical data , Duodenal Ulcer/surgery , Female , Follow-Up Studies , Gastroenterostomy/statistics & numerical data , Humans , Incidence , Laryngeal Neoplasms/epidemiology , Longitudinal Studies , Male , Rectal Neoplasms/epidemiology , Risk Factors , Scotland/epidemiology , Smoking/epidemiology , Stomach Neoplasms/epidemiology
12.
Biotechnol Lett ; 28(1): 45-50, 2006 Jan.
Article in English | MEDLINE | ID: mdl-16369874

ABSTRACT

Dried milled biomass of Azolla filiculoides removed up to 98.2% of gold from wastewater from a gold plating factory containing 5 mg gold/l in solution in batch biosorption. The gold uptake capacity of the biomass was 98 mg/g. Whole dried biomass used in a continuous flow column removed up to 100% of gold from diluted wastewater. A similar column was linked to a sulphide precipitation process to provide a two-step system which was able to remove 98% of gold from undiluted wastewater containing 41 mg Au/l. The lifetime of the column was five days.


Subject(s)
Biomass , Ferns , Gold/isolation & purification , Industrial Waste , Waste Disposal, Fluid/methods , Water Purification/methods , Adsorption , Biodegradation, Environmental
13.
IEEE Trans Biomed Eng ; 50(7): 890-9, 2003 Jul.
Article in English | MEDLINE | ID: mdl-12848357

ABSTRACT

A novel expanded tip wire (ETW) catheter antenna is proposed for microwave ablation for the treatment of atrial fibrillation (AF). The antenna is designed as an integral part of coaxial cable so that it can be inserted via a 6F catheter. A numerical model based on the rotationally symmetric finite-difference time-domain technique incorporating the generalized perfectly matched layer as the absorbing boundary condition has been utilized to accurately model the interaction between the antenna and the myocardium. Numerical and in-vitro experimental results are presented for specific absorption rate, return loss and heating pattern produced by the antenna. Both numerical modeling and in-vitro experimentation show that the proposed ETW antenna produces a well-defined electric field distribution that provides continuous long and linear lesions for the treatment of AF.


Subject(s)
Atrial Fibrillation/therapy , Catheter Ablation/instrumentation , Electrodes , Heart Ventricles/radiation effects , Microwaves/therapeutic use , Animals , Atrial Fibrillation/physiopathology , Catheter Ablation/methods , Cattle , Computer-Aided Design , Dose-Response Relationship, Radiation , Equipment Design/methods , Feasibility Studies , Heart Ventricles/physiopathology , Hot Temperature/therapeutic use , Radiometry/methods , Reproducibility of Results , Sensitivity and Specificity , Therapy, Computer-Assisted/methods
14.
Placenta ; 24(7): 786-9, 2003 Aug.
Article in English | MEDLINE | ID: mdl-12852870

ABSTRACT

Intrauterine infection has been associated with fetal brain injury and preterm birth. We have recently shown that repeated exposure to bacterial endotoxin leads to hypoxia and brain injury in the preterm ovine fetus and we considered it possible that endotoxin could also damage the placenta. Our aim therefore was to assess placental structure following repeated exposure to endotoxin. Endotoxin was administered on 3-5 occasions (1 microg/kg, i.v.) over 5 days from 95-99 days of gestation (term approximately 147 days) to 6 fetal sheep and placental structure assessed at 105 days. In LPS-exposed animals there was a 17 per cent reduction (P<0.05) in placental weight and the average cross-sectional area of placentomes was reduced (P<0.05) by 20 per cent. In addition, all LPS-exposed placentae showed significant injury as evidenced by calcium deposits associated with areas of infarcted tissue. We conclude that repeated endotoxin exposure results in damage to the placenta which could lead to persistent alterations in placental exchange function.


Subject(s)
Lipopolysaccharides/toxicity , Placenta/drug effects , Pregnancy Complications, Infectious , Sheep , Animals , Calcinosis/chemically induced , Calcinosis/pathology , Disease Models, Animal , Female , Infarction/chemically induced , Infarction/pathology , Injections, Intravenous , Lipopolysaccharides/administration & dosage , Maternal-Fetal Exchange/drug effects , Organ Size/drug effects , Placenta/blood supply , Placenta/pathology , Pregnancy , Pregnancy Complications, Infectious/pathology , Pregnancy Complications, Infectious/physiopathology
15.
Pacing Clin Electrophysiol ; 26(6): 1379-85, 2003 Jun.
Article in English | MEDLINE | ID: mdl-12822755

ABSTRACT

Radiofrequency (RF) ablation of pulmonary veins (PVs) is a new treatment for atrial fibrillation. Low energy ablation is usually used for this procedure. The effect of superfusate flow on lesion formation in this setting has not been studied previously. We examined lesion dimensions and intramural temperatures with varying powers and duration of RF application in this high flow environment. Ablation of fresh bovine hearts was performed with a 4-mm tip RF catheter in temperature control mode, target temperature 50 degrees C. At power levels of 20 W, 30 W, 40 W, and 50 W, effects of PV flow (no flow or 1 L/min) and 60- and 120-second durations were tested. Tissue temperatures were recorded at depths of 1, 4, 7, and 10 mm. Without flow, no lesions were created. The lowest power setting for lesion creation was 30 W at 60 seconds and 20 W at 120 seconds. Increasing power from 30 W to 50 W for 60 seconds increased lesion depth 0.7 mm (SE 0.3), P = 0.03 and 2.5 mm (SE 0.6), P = 0.003, at 120 seconds. Increasing RF application duration from 60 to 120 seconds increased depth for 30 W by 0.9 mm (SE 0.5), P = NS, 40 W 1.7 mm (SE 0.4), P = 0.002, and 50 W 2.6 mm (SE 0.5), P < 0.001. Power of 50 W for 60 seconds and >30 W for 120 seconds created lesions deeper than the wall thickness of a PV. Flow is necessary for creation of lesions with low power, low tip temperature RF ablation. When a resistant site to ablation is encountered, increasing duration of ablation is best for increasing lesion depth. Higher power has the potential to create lesions deeper than the PV wall and may increase the risk of complications.


Subject(s)
Catheter Ablation/methods , Pulmonary Veins , Animals , Blood Flow Velocity , Cattle , Electric Stimulation , Heart Ventricles , In Vitro Techniques
16.
Ann Thorac Surg ; 75(2): 543-8, 2003 Feb.
Article in English | MEDLINE | ID: mdl-12607670

ABSTRACT

BACKGROUND: The optimal technique for producing linear radiofrequency thermal lesions in myocardial tissue is unclear. We compared epicardial ablation on the beating heart with endocardial ablation after cardioplegia. METHODS: Radiofrequency lesions were produced using a multielectrode malleable handheld probe in ovine myocardium with three wall thicknesses. Detailed analysis of lesion dimensions was used to assess the effects of site of ablation, muscle thickness, and duration of ablation. RESULTS: After epicardial atrial ablation, myocardial lesions were detected in all sections without macroscopically visible epicardial fat (n = 10), but only 43% (6/14) of sections with epicardial fat. Three of 24 atrial epicardial sections (13%) and 92% (23/25) of endocardial atrial lesion sections were clearly transmural. In thicker tissues lesion depth was independent of endocardial (right ventricle: 3.9 +/- 1.1 mm, left ventricle: 3.8 +/- 0.7 mm) or epicardial (right ventricle: 3.4 +/- 0.6 mm, left ventricle: 4.3 +/- 0.9 mm) ablation site. Epicardial lesions are less deep in thinner areas of myocardium (p = 0.003). Lesions were all wider than they were deep. There was no significant increase in lesion depth with the increase in ablation duration from 1 to 2 minutes. CONCLUSIONS: Lesions were unlikely to be transmural with either technique when the wall thickness was greater than about 4 mm. Epicardial fat has an important negative effect on epicardial lesion formation. Where epicardial fat is absent epicardially produced lesions penetrate less deeply when the wall thickness is small, possibly due to endocardial cooling by circulating blood. Prolongation of the duration of ablation from 1 to 2 minutes does not significantly increase lesion depth.


Subject(s)
Catheter Ablation/methods , Heart Conduction System/surgery , Animals , Catheter Ablation/instrumentation , Heart Conduction System/pathology , Models, Animal , Myocardium/pathology , Sheep
17.
Ann Vasc Surg ; 16(2): 242-5, 2002 Mar.
Article in English | MEDLINE | ID: mdl-11972261

ABSTRACT

Primary aortoenteric fistula is such a rare condition that even specialist vascular surgeons may not encounter one in their lifetime practice. Any hope of survival depends upon prompt diagnosis and surgical treatment. We present our experience of one such case, particularly the difficulties encountered in confirming the diagnosis, and go on to review the literature on the subject. Both our experience and that reported by previous authors would suggest that specialized investigations such as computed tomography, contrast angiography, radionuclide scintigraphy, and gastrointestinal endoscopy have only a limited contribution to make in confirming the diagnosis of primary aortoenteric fistula. The diagnosis should be considered in any patient with gastrointestinal blood loss and an abdominal aortic aneurysm. Specialized investigations should not be relied upon to confirm or refute the diagnosis. Any prospect of survival is dependant upon prompt diagnosis and surgical intervention. The latter is only achieved by a high index of clinical suspicion.


Subject(s)
Aortic Aneurysm, Abdominal/diagnosis , Gastrointestinal Hemorrhage/etiology , Intestinal Fistula/diagnosis , Vascular Fistula/diagnosis , Aged , Diagnosis, Differential , Duodenal Diseases/diagnostic imaging , Fatal Outcome , Female , Humans , Intestinal Fistula/complications , Tomography, X-Ray Computed , Vascular Fistula/complications
18.
Bone Marrow Transplant ; 27(11): 1215-7, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11551034

ABSTRACT

We report the case of a 46-year-old male who developed dermatomyositis and a sarcoid-like reaction in association with testicular relapse of multiple myeloma. The myositis progressed despite chemotherapy directed at the underlying malignant disorder and immunosuppressive treatment. There was, however, a dramatic and sustained response to high-dose chemotherapy and autologous peripheral blood stem cell transplantation which resulted in resolution of the myopathy and partial resolution of the sarcoid-like reaction. This case report highlights the potential of autologous stem cell transplantation as treatment for para-neoplastic disorders associated with haematological malignancies.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Dermatomyositis/therapy , Hematopoietic Stem Cell Transplantation , Multiple Myeloma/complications , Sarcoidosis/therapy , Combined Modality Therapy , Dermatomyositis/diagnosis , Dermatomyositis/etiology , Humans , Male , Middle Aged , Multiple Myeloma/therapy , Recurrence , Sarcoidosis/diagnosis , Sarcoidosis/etiology , Testicular Neoplasms/therapy , Treatment Outcome
19.
Sleep ; 24(4): 418-24, 2001 Jun 15.
Article in English | MEDLINE | ID: mdl-11403526

ABSTRACT

STUDY OBJECTIVES: To determine whether older people with age-related sleep maintenance problems have significantly lower melatonin levels than comparable normal sleepers. DESIGN: Case-control study. SETTING: A largely urban population, Auckland, New Zealand. PARTICIPANTS: People over the age of 65 years, who either slept normally, or had age-related sleep maintenance problems. Participants were recruited through media advertising, and local interest groups. Initial screening was by mail (Pittsburgh Sleep Quality Index), followed by interviews at a hospital day clinic. Exclusions included those with depression, cognitive impairment, medical and/or environmental problems which might impair sleep. INTERVENTIONS: N/A. MEASUREMENTS AND RESULTS: A metabolite of plasma melatonin, 6-sulphatoxymelatonin (aMT6s) was measured in the urine of 57 normal sleepers, and 53 people with age-related problems over 24 hours in three aliquots: 12:00-19:00h, 19:00-07:00h, 07:00-12:00h. There were clear differences in self reported quality of sleep but no difference in mean aMT6s 24 hour or total night excretory levels, or night/day ratios. CONCLUSIONS: Older people with age-related sleep maintenance problems do not have lower melatonin levels than older people reporting normal sleep.


Subject(s)
Aging/physiology , Melatonin/blood , Melatonin/urine , Sleep Wake Disorders/blood , Sleep Wake Disorders/urine , Aged , Aged, 80 and over , Case-Control Studies , Female , Humans , Male
SELECTION OF CITATIONS
SEARCH DETAIL
...