ISSN:0954-6820    

DOI:10.1046/j.1365-2796.1996.478811000.x

出版商:Blackwell Science Ltd    

年代:1996

数据来源: WILEY

摘要:

Hallqvist Jet al.(Institute of Environmental Medicine and Department of International Health and Social Medicine, Karolinska Institute, Stockholm, Sweden). How to evaluate interaction between causes: a review of practices in cardiovascular epidemiology (Review).J Intern Med1996;239:377–82.To increase the knowledge of interaction or synergy between risk factors is an important task in medical research. Still, current literature in cardiovascular epidemiology reflects major misconceptions as how to evaluate interaction. This paper presents Rothman's model of causation from which strict empirical criteria of interaction can be derived. In principle, the method to apply consists of comparing risk differences for one risk factor of interest across strata of the other. Commonly used but incorrect approaches are exemplified and discussed. These include reporting risk of disease among those with combined exposure, comparing relative risks for one exposure after stratification by level of the other, and including an interaction term in the regression model and drawing conclusions from itsP‐va

ISSN:0954-6820    

DOI:10.1046/j.1365-2796.1996.431782000.x

出版商:Blackwell Science Ltd    

年代:1996

数据来源: WILEY

摘要:

Boonen S, Dequeker J (Department of Internal Medicine, Divisions of Geriatric Medicine and Rheumatology, and the Arthritis and Metabolic Bone Disease Research Unit, Katholieke Universiteit, Leuven, Belgium). Strategies for the prevention of senile (type II) osteoporosis: an update (Review).J Intern Med1996;239:383–91.Hip fractures in the elderly represent a global issue, associated with significant morbidity and mortality. Considering the magnitude of the problem, any substantial reduction in the hip fracture burden depends on prevention. In view of the complex pathogenesis of senile (type II) osteoporosis, preventive strategies should focus on the frequency of falling in the elderly as well as on the prevalence of compromised femoral integrity as a consequence of bone loss. Although many risk factors for senile osteoporosis are potentially preventible or reversible with targeted interventions, the beneficial effects of most strategies have not yet been adequately documented, indicating the need for additional long‐term controlled stud

ISSN:0954-6820    

DOI:10.1046/j.1365-2796.1996.427779000.x

出版商:Blackwell Science Ltd    

年代:1996

数据来源: WILEY

摘要:

Bonnema SJ, Møller J, Marving J, Kvetny J (Departments of Internal Medicine and Clinical Physiology and Nuclear Medicine, Esbjerg Centralsygehus, Esbjerg, Denmark). Sarcoidosis causes abnormal seasonal variation in 1,25‐dihydroxy‐cholecalciferol.J Intern Med1996;239: 393–98.Objectives.The spontaneous seasonal variations in the calcium regulating hormones 1,25‐dihydroxy‐cholecalciferol (1,25‐DHCC) and parathyroid hormone (PTH) were investigated in patients with sarcoidosis.Design.Controlled, prospective observational study with measurements in the winter and summer seasons, respectively.Subjects.Twelve patients (age: median 33, range 21–54 years) with biopsy‐verified (n=8) sarcoidosis were included as well as 11 age‐matched healthy control subjects.Main outcome measures.Serum values of calcium, ionized calcium, phosphate, chloride, bicarbonate, creatinine, albumin, angiotensin‐converting enzyme, alkaline phosphatase, 1,25‐DHCC, and PTH. Also, 24‐h whole‐body retention of 99mTc methylene‐diphosphonate was assessed.Results.The patient group showed an increased level of 1,25‐DHCC in the summer season (w:146±67, s:198±73 pmol L‐1;P<0.01) in contrast to the opposite finding among controls (w:161±34, s:144±43 pmol L‐1;P<0.05). Comparing the individual seasonal changes between the two groups, the difference was marked (P<0.001). Compared with controls, total serum calcium was elevated in the summer season in the patient group (P<0.05), in which the same parameter correlated positively with 1,25‐DHCC (r=0.658;P<0.01). PTH was increased two to three times above the control values throughout the year (patients: w:0.37±0.13, s:0.24±0.08 μg L‐1; controls: w:0.14±0.09, s:0.10±0.04 μg L‐1;P<0.001); although, the level of this hormone was still found within the reference interval. 24‐h whole body bone scintigraphy failed to show any seasonal variation in bone metabolism. In contrast, serum alkaline phosphatase was found to be increased during the summer season compared with the control group (P<0.001). Angiotensin‐converting enzyme showed no seasonal variation.Conclusions.In sarcoidosis, 1,25‐DHCC is abnormally regulated throughout the year, with a significantly higher serum level in the summer season. Uncontrolled production of 1,25‐DHCC in sarcoid pulmonary alveolary macrophages is possibly responsible for hypercalcaemic episodes, and thi

ISSN:0954-6820    

DOI:10.1046/j.1365-2796.1996.472813000.x

出版商:Blackwell Science Ltd    

年代:1996

数据来源: WILEY

摘要:

Tuominen JA, Eriksson JG, Koivisto VA (Department of Medicine, Helsinki University Central Hospital, and National Institute of Public Health, Helsinki, Finland). Acute administration of metoprolol and enalaprilat reduces insulin‐stimulated thermogenesis and skin blood flow.J Intern Med1996;239: 399–406.Objective.To examine the acute effects of intravenous metoprolol and enalaprilat on energy expenditure, thermogenesis, blood flow and insulin sensitivity.Design.Randomized, single‐blind, placebo‐controlled trial.Setting.Helsinki University Central Hospital, Finland.Subjects.Seven moderately insulin‐resistant nondiabetic subjects.Interventions.Each subject was studied three times at 2–3 weeks intervals; metoprolol (5 mg), enalaprilat (2 mg) or saline infusions were used.Methods.A 150‐min euglycaemic/hyperinsulinaemic clamp combined with indirect calorimetry and blood flow measurements were performed.Main outcome measures.Glucose uptake, forearm and skin blood flow, and energy expenditure.Results.Blood pressure was decreased to the same degree by both drugs. Forearm blood flow (plethysmography) was lower with metoprolol compared to enalaprilat (2.1±0.2 vs. 2.8±0.4 mL per 100 mL min‐1;P<0.05). Glucose‐plus‐insulin‐stimulated thermogenesis and total energy expenditure were reduced both by metoprolol (71 and 5.2%;P<0.05 in both) and enalaprilat (59%,P= 0.06; and 7.6%,P<0.05) as compared to the control study. Skin blood flow (laser Doppler) increased by 100% (P<0.01) during the glucose‐plus‐insulin infusion, but this increment was inhibited by both drug infusions. Forearm and whole‐body glucose uptake was not influenced by metoprolol or enalaprilat administration.Conclusions.(i) Both metoprolol and enalaprilat inhibit glucose‐plus‐insulin‐induced thermogenesis and a rise in skin blood flow. (ii) Metoprolol further reduces forearm blood flow compared to enalaprilat. (iii) Neither drug has any acute effect on insulin sensitivity. (iv) The interference of a physiological response to insulin by ACE inhibitors or beta‐blocking agents may have implications both for energy balance and thermoregulation durin

ISSN:0954-6820    

DOI:10.1046/j.1365-2796.1996.473824000.x

出版商:Blackwell Science Ltd    

年代:1996

数据来源: WILEY

摘要:

Aakhus S, Dahl S, Widerøe TE (Sections of Cardiology and Nephrology, Department of Medicine, University Hospital of Trondheim, Trondheim, Norway). Hyperlipidaemia in renal transplant patients.J Intern Med1996;239:407–15.Objectives.The aim of study was to assess the prevalence and severity of hyperlipidaemia in renal transplant patients in a Nordic country.Design.Multicentre, cross‐sectional study.Setting.Outpatients and ward inpatients registered from 23 hospitals covering all regions of the country.Subjects.Renal transplant patients with a functioning graft were registered: 406 patients in all; that is, 43% of the national renal transplant population. All patients used prednisolone, 71% used cyclosporine, either with (51%) or without (20%) azathioprine. Total cholesterol values from general population were obtained from a national survey.Main outcome measures.Blood lipids and their relation to clinical parameters.Results.Total cholesterol was significantly higher in transplant patients than in the general population for both genders and all age groups (P<0.01). Female patients had higher total cholesterol (mean±SD: 7.49±1.61mmolL‐1) than males (7.01±1.55mmolL‐1;P<0.001), and also higher HDL cholesterol (1.55±0.43 vs. males: 1.32±0.46mmolL‐1;P<0.001). Triglycerides were equally elevated in both genders, and 33% had values above 2.2mmolL‐1. Reduced creatinine clearance, a high body‐mass index, female gender, hypertension, and coronary artery disease were independently associated with higher total cholesterol. Beta blockers were associated with lower HDL cholesterol and higher triglycerides, and diuretics with higher triglycerides. Blood lipid levels were not associated with cyclosporine immunosuppression.Conclusion.Hyperlipidaemia is prevalent after renal transplantation, and is associated with impaired graft function, hypertension, and with the use of beta blockers and diuretics, but not with the

ISSN:0954-6820    

DOI:10.1046/j.1365-2796.1996.474825000.x

出版商:Blackwell Science Ltd    

年代:1996

数据来源: WILEY

摘要:

Hublin C, Kaprio J, Partinen M, Heikkilä K, Koskenvuo M (Departments of Psychiatry and Neurology and the Department of Public Health (The Finnish Twin Cohort), University of Helsinki, Helsinki; and the Department of Public Health, University of Turku, Turku; Finland). Daytime sleepiness in an adult, Finnish population.J Intern Med1996;239:417–23.Objectives.To investigate the prevalence of and the factors associated with daytime sleepiness occurring every or almost every day.Design.A cross‐sectional, questionnaire survey.Subjects.A total of 11354 adults (aged 33–60 years) representative of the Finnish population.Main outcome measures.Frequency of daytime sleepiness, naps and sleep attacks; occurrence of emotion‐associated muscle weakness, sleep debt, insomnia, sleep apnoeas and type of snoring; Beck Depression Inventory score; and the use of hypnotics and tranquillisers.Results.A total of 11.0% of women and 6.7% of men suffered from daytime sleepiness every or almost every day. Amongst those with sleepiness (n= 1026) 19.5% of women and 42.3% of men reported snoring 3 nights per week, 25% had scores suggesting moderate to severe depression, 11% used hypnotics or tranquilizers on more than 180 days per year, and 9% reported insufficient sleep. Insomnia at least every other day was reported by 20.7% of women and by 28.6% of men. Amongst those with sleepiness, narcolepsy was found in 0.3%, with the diagnosis confirmed in a sleep laboratory evaluation.Conclusions.Daytime sleepiness occurring daily or almost daily is most often associated with depression, insomnia and sleep‐disordered breathing. In most cases, indications of the cause of sleepiness can be obtained by using simple screening

ISSN:0954-6820    

DOI:10.1046/j.1365-2796.1996.475826000.x

出版商:Blackwell Science Ltd    

年代:1996

数据来源: WILEY

摘要:

Persson J, Israelsson B, Stavenow L, Holmström E, Berglund G (Department of Medicine, Lund University Hospital, Malmö, Sweden). Progression of atherosclerosis in middle‐aged men: effects of multifactorial intervention.J Intern Med1996;239: 425–33.Objective.To determine the effect of multifactorial intervention against cardiovascular risk factors on ultrasound‐determined progression of atherosclerosis in healthy middle‐aged men.Design.One hundred and forty‐nine healthy middle‐aged men were assigned to an intervention group (IG) or a control group (CG).Subjects.The participants had moderately increased risk‐factor scores for cardiovascular disease. They were recruited from a health screening programme at the Preventive Medicine Section, Department of Medicine, Lund University, University Hospital, Malmö. During the study period, 32 of the subjects were lost to follow‐up, leaving 59 in the IG and 58 in the CG.Intervention.The IG subjects underwent multifactorial intervention for 2 years, the goal being to help them stop smoking and to reduce their blood lipids and blood pressure.Main outcome measures.Intima–media thickness and plaque score in the right carotid artery were ultrasonographically determined initially and after 2 years. Blood lipids and blood pressure were measured at the same time, and in the IG also after 3, 6, 12 and 18 months after entry into the study.Results.At the entry into the study, there were no significant differences in major risk factors or ultrasound variables between IG and CG. Blood lipids and smoking decreased significantly during the 2 years of intervention in the IG, whilst these factors remained unchanged in the CG. Intima–media thickness and plaque scores increased significantly in both groups.Conclusions.No effects on ultrasound variables could be detected after 2 years of multifactorial intervention. A more aggressive intervention programme, possibly more dependent on pharmacological treatment, may be required to obtain reduced progression or regress

ISSN:0954-6820    

DOI:10.1046/j.1365-2796.1996.476814000.x

出版商:Blackwell Science Ltd    

年代:1996

数据来源: WILEY

摘要:

Targher G, Seidell JC, Tonoli M, Muggeo M, De Sandre G, Cigolini M (Division of Endocrinology and Metabolic Diseases, Institute of Clinical Medicine, University of Verona, Italy; and Department of Chronic Diseases and Environmental Epidemiology‐RIVM, Bilthoven, The Netherlands). The white blood cell count: relationship to plasma insulin and other cardiovascular risk factors in healthy males.J Intern Med1996;239:435–41.Objectives.To evaluate the relationships of total and differential white blood cell (WBC) count to the components of the so‐called insulin resistance syndrome.Subjects and design.The study population consisted of a random sample of 90 38‐year‐old healthy men with normal glucose tolerance.Interventions.A 75 g oral glucose tolerance test was performed in all participants.Main outcome measures.Total and differential WBC count, lipids, blood pressure, plasma glucose, C‐peptide and insulin (at fasting and 2 h after glucose load).Results.Total WBC count correlated consistently with plasma 2‐h glucose (r=0.38;P<0.001), fasting and 2‐h postload insulin (r=0.26 andr=0.33;P<0.01–0.001, respectively) and C‐peptide (r=0.28 andr=0.32;P<0.01–0.001) concentrations. Smokers had significantly higher total leukocytes (P<0.01), neutrophils and lymphocytes than nonsmokers. Furthermore, total WBC count correlated positively with body mass index, blood pressure, plasma triglycerides, fibrinogen, and negatively with HDL cholesterol concentration. As differential WBC count, most variables correlated essentially to neutrophils and/or lymphocytes, whereas plasma insulin and C‐peptide concentrations correlated essentially to lymphocytes and monocytes, but not to neutrophils. In a multiple linear regression analysis, only 2‐h plasma glucose (P<0.01) and fibrinogen (P<0.05) were positive predictors of total WBC count after adjusting for all potentially confounding variables.Conclusions.The results indicate that increased, albeit normal, WBC count associates with the cluster of metabolic and haemodynamic disorders typical of the insulin resistance syndrome, and suggest that increased WBC count may be yet another c

ISSN:0954-6820    

DOI:10.1046/j.1365-2796.1996.815000.x

出版商:Blackwell Science Ltd    

年代:1996

数据来源: WILEY

摘要:

Koskinen P, Virolainen J, Koskinen Pk, Häyry P, Kupari M (Division of Cardiology, Department of Medicine, Helsinki University Central Hospital, and Transplantation Laboratory, University of Helsinki, Helsinki, Finland). Evolution of heart rate variability in cardiac transplant recipients: a clinical study.J Intern Med1996;239: 443–9.Objectives.To investigate in cardiac transplant patients whether post‐transplantation time, graft arteriosclerosis, allograft rejection, or earlier cytomegalovirus infection affect the neural regulatory mechanisms of the donor heart.Design.A consecutive series of heart transplant patients during a 12‐month period.Setting.A university hospital in Finland.Subjects.Consecutive cardiac transplant recipients (n=38) attending the hospital for their annual clinical examintaion were studied. Their mean (SD) age was 45.4 (11.5) years, 37 were male, and the median (range) time since transplantation was 36 (12–72) months.Interventions.Power spectral analysis of R–R intervals (during 5 min of controlled breathing, the Valsalva manoeuvre, and deep breathing), routine coronary arteriography, cytomegalovirus serology.Results.R–R interval (r=0.67;P<0.001), the root mean square difference of successive R–R intervals (r=0.38;P<0.05), the total R–R interval power (r=0.45;P<0.01), the power of the very low frequency (0.0–0.07 Hz) component (r=0.53;P<0.01), and the power of the nonrespiratory (0.0–0.15 Hz) component (r=0.49;P<0.01) were related to the length of time since the operation. Patients having had a transplantation 3 years ago or more had significantly greater median (range) total R–R interval power than those having had the operation less than 3 years ago (59 [10–265] vs. 20 [3–113]ms2;P=0.02). There was also a difference between the two groups in the very low frequency component (18 [1–226] vs. 5 [0–45]ms2;P=0.01), in the nonrespiratory component (30 [1–227] vs. 9 [0–53]ms2;P=0.02), and in the Valsalva ratio (0.995 [0.955–1.065] vs. 1.020 [0.975–1.155];P=0.03). Patients with and without graft arteriosclerosis, episodes of rejection, or earlier cytomegalovirus infection showed no difference in the power spectral measures.Conclusions.The donor heart rate variability increases with post‐transplantation time. Heart rate variability in transplant recipients is not related to the extent of graft arteriosclerosis, episodes of allograft rejecti

ISSN:0954-6820    

DOI:10.1046/j.1365-2796.1996.480816000.x

出版商:Blackwell Science Ltd    

年代:1996

数据来源: WILEY