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Dive into the research topics where Ola Samuelsson is active.

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Featured researches published by Ola Samuelsson.


The Lancet | 2005

Should beta blockers remain first choice in the treatment of primary hypertension? A meta-analysis.

Lars Lindholm; Bo Carlberg; Ola Samuelsson

BACKGROUND Beta blockers have been used widely in the treatment of hypertension and are recommended as first-line drugs in hypertension guidelines. However, a preliminary analysis has shown that atenolol is not very effective in hypertension. We aim to substantially enlarge the data on atenolol and analyse the effect of different beta blockers. METHODS The Cochrane Library and PubMed were searched for beta blocker treatment in patients with primary hypertension. Data were then entered into the Cochrane Collaboration Review Manager package and were summarised in meta-analyses. 13 randomised controlled trials (n=105 951) were included in a meta-analysis comparing treatment with beta blockers with other antihypertensive drugs. Seven studies (n=27 433) were included in a comparison of beta blockers and placebo or no treatment. FINDINGS The relative risk of stroke was 16% higher for beta blockers (95% CI 4-30%) than for other drugs. There was no difference for myocardial infarction. When the effect of beta blockers was compared with that of placebo or no treatment, the relative risk of stroke was reduced by 19% for all beta blockers (7-29%), about half that expected from previous hypertension trials. There was no difference for myocardial infarction or mortality. INTERPRETATION In comparison with other antihypertensive drugs, the effect of beta blockers is less than optimum, with a raised risk of stroke. Hence, we believe that beta blockers should not remain first choice in the treatment of primary hypertension and should not be used as reference drugs in future randomised controlled trials of hypertension.


The Lancet | 2004

Atenolol in hypertension: is it a wise choice?

Bo Carlberg; Ola Samuelsson; Lars Lindholm

BACKGROUND Atenolol is one of the most widely used beta blockers clinically, and has often been used as a reference drug in randomised controlled trials of hypertension. However, questions have been raised about atenolol as the best reference drug for comparisons with other antihypertensives. Thus, our aim was to systematically review the effect of atenolol on cardiovascular morbidity and mortality in hypertensive patients. METHODS Reports were identified through searches of The Cochrane Library, MEDLINE, relevant textbooks, and by personal communication with established researchers in hypertension. Randomised controlled trials that assessed the effect of atenolol on cardiovascular morbidity or mortality in patients with primary hypertension were included. FINDINGS We identified four studies that compared atenolol with placebo or no treatment, and five that compared atenolol with other antihypertensive drugs. Despite major differences in blood pressure lowering, there were no outcome differences between atenolol and placebo in the four studies, comprising 6825 patients, who were followed up for a mean of 4.6 years on all-cause mortality (relative risk 1.01 [95% CI 0.89-1.15]), cardiovascular mortality (0.99 [0.83-1.18]), or myocardial infarction (0.99 [0.83-1.19]). The risk of stroke, however, tended to be lower in the atenolol than in the placebo group (0.85 [0.72-1.01]). When atenolol was compared with other antihypertensives, there were no major differences in blood pressure lowering between the treatment arms. Our meta-analysis showed a significantly higher mortality (1.13 [1.02-1.25]) with atenolol treatment than with other active treatment, in the five studies comprising 17671 patients who were followed up for a mean of 4.6 years. Moreover, cardiovascular mortality also tended to be higher with atenolol treatment than with other antihypertensive treatment. Stroke was also more frequent with atenolol treatment. INTERPRETATION Our results cast doubts on atenolol as a suitable drug for hypertensive patients. Moreover, they challenge the use of atenolol as a reference drug in outcome trials in hypertension.


American Journal of Kidney Diseases | 1993

Lipoprotein Metabolism and Renal Failure

Per-Ola Attman; Ola Samuelsson; Petar Alaupovic

Lipoprotein metabolism is altered in the majority of patients with renal insufficiency and renal-failure, but may not necessarily lead to hyperlipidemia. The dyslipoproteinemia of renal disease has characteristic abnormalities of the apolipoprotein (apo) profile and lipoprotein composition. It develops during the asymptomatic stages of renal insufficiency and becomes more pronounced as renal failure advances. The qualitative characteristics of renal dyslipoproteinemia are not modified substantially by dialysis treatment. Patients with chronic renal disease may therefore be exposed to dyslipoproteinemia for long periods of time. The characteristic plasma lipid abnormality is a moderate hypertriglyceridemia. The alterations of lipoprotein metabolism affect both the apoB-containing very low-density and intermediate-density, and low-density lipoproteins and the apoA-containing high-density lipoproteins. The main underlying abnormality of lipoprotein transport is a decreased catabolism of the apoB-containing lipoproteins caused by decreased activity of lipolytic enzymes and altered lipoprotein composition. There is an increase of intact or partially metabolized, triglyceride-rich, apoB-containing lipoproteins with a disproportionate elevation of apoC-III and, to a lesser extent, apoE, resulting in a marked increase of the intermediate-density lipoproteins and an enrichment of triglycerides, apoC-III, and apoE in the low-density lipoproteins. In high-density lipoproteins there are decreases in the concentrations of cholesterol, apolipoproteins A-I and A-II, and the high-density lipoprotein-2 to high-density lipoprotein-3 ratio. These abnormalities result in a characteristic decrease of the apoA-I to apoC-III ratio and anti-atherogenic index apoA-I/apoB. The pathophysiologic links between the renal insufficiency and the abnormalities of lipoprotein transport are still poorly defined. Changes in the action of insulin on lipolytic enzymes, possibly mediated via increased levels of parathyroid hormone, have been suggested to play a contributory role. The clinical consequences of a defective lipoprotein transport may be related to the atherogenic character of lipoprotein abnormalities. Renal dyslipoproteinemia may contribute to the development of atherosclerotic vascular disease and progression of glomerular and tubular lesions with subsequent deterioration of renal function. Dietary and/or pharmacologic intervention may ameliorate the uremic dyslipoproteinemia, but the long-term clinical effects of such treatment have yet to be established.


Journal of Hypertension | 1985

Predictors of cardiovascular morbidity in treated hypertension: results from the primary preventive trial in Göteborg, Sweden.

Ola Samuelsson; Lars Wilhelmsen; Dag Elmfeldt; Kjell Pennert; Hans Wedel; John Wikstrand; Göran Berglund

Prognostic factors for cardiovascular disease (CVD) were studied in treated, middle-aged male hypertensives, derived from a random population sample and followed for more than 10 years. In multivariate analysis diastolic blood pressure, smoking, serum cholesterol, proteinuria, angina pectoris and previous stroke were found to be independent predictors of CVD morbidity (non-fatal myocardial infarction (MI), non-fatal stroke, or CVD death). Multivariate analyses for coronary heart disease (CHD), stroke and CVD mortality were also performed and the results are given. Life-table analyses showed a three times higher CVD incidence among smokers than amongst non-smokers and a doubled incidence for subjects with a serum cholesterol in the highest quartile, i.e. above 7.3 mmol/l, compared with those with levels below, and a three times higher incidence for subjects with proteinuria than those without. Non-smokers with a serum cholesterol below 7.3 mmol/l and free of any hypertensive organ manifestation at entry did not differ significantly in CVD morbidity from a normotensive comparison group that was derived from the same population sample. These findings in a well-defined population sample show that in spite of treatment for hypertension the CVD risk is still substantial if organ damage or other risk factors are present. These findings underline the importance of multiple risk intervention.


Nephrology Dialysis Transplantation | 2012

Best supportive care and therapeutic plasma exchange with or without eculizumab in Shiga-toxin-producing E. coli O104:H4 induced haemolytic–uraemic syndrome: an analysis of the German STEC-HUS registry

Jan T. Kielstein; Gernot Beutel; Susanne V. Fleig; Jürgen Steinhoff; Tobias N. Meyer; Carsten Hafer; Uwe Kuhlmann; Jörn Bramstedt; Ulf Panzer; Martin Vischedyk; Veit Busch; Wolfgang Ries; Steffen Mitzner; Stefan Mees; Sylvia Stracke; Jens Nürnberger; Peter Gerke; Monika Wiesner; Bernd Sucke; Miriam Abu-Tair; Andreas Kribben; Norbert Klause; Ralf Schindler; Frank Merkel; Sabine Schnatter; Eiske M. Dorresteijn; Ola Samuelsson; Reinhard Brunkhorst

BACKGROUND May 22nd marks the beginning of a Shiga-toxin-producing Escherichia coli (STEC) O104:H4 outbreak in Northern Germany. By its end on 27 July, it had claimed 53 deaths among 2987 STEC and 855 confirmed haemolytic-uraemic syndrome (HUS) cases. METHODS To describe short-term effectiveness of best supportive care (BSC), therapeutic plasma exchange (TPE) and TPE with eculizumab (TPE-Ecu) in 631 patients with suspected HUS treated in 84 hospitals in Germany, Sweden and the Netherlands using the web-based registry of the DGfN (online since 27 May). RESULTS Of 631 entries, 491 fulfilled the definition of HUS (median age 46 years; 71% females). The median (inter-quartile range) hospital stay was 22 (14-31) days. Two hundred and eighty-one (57%) patients underwent dialysis and 114 (23%) mechanical ventilation. Fifty-seven patients received BSC, 241 TPE and 193 TPE-Ecu. Treatment strategy was dependent on disease severity (laboratory signs of haemolysis, thrombocytopenia, peak creatinine level, need for dialysis, neurological symptoms, frequency of seizures) which was lower in BSC than in TPE and TPE-Ecu patients. At study endpoint (hospital discharge or death), the median creatinine was lower in BSC [1.1 mg/dL (0.9-1.3)] than in TPE [1.2 mg/dL (1.0-1.5), P < 0.05] and TPE-Ecu [1.4 mg/dL (1.0-2.2), P < 0.001], while need for dialysis was not different between BSC (0.0%, n = 0), TPE (3.7%; n = 9) and TPE-Ecu (4.7%, n = 9). Seizures were absent in BSC and rare in TPE (0.4%; n = 1) and TPE-Ecu (2.6%; n = 5) patients. Total hospital mortality in HUS patients was 4.1% (n = 20) and did not differ significantly between the TPE and TPE-Ecu groups. CONCLUSIONS Despite frequent renal impairment, advanced neurological disorders and severe respiratory failure, short-term outcome was better than expected when compared with previous reports. Within the limitations of a retrospective registry analysis, our data do not support the notion of a short-term benefit of Ecu in comparison to TPE alone in the treatment of STEC-HUS. A randomized trial comparing BSC, TPE and Ecu seems to be prudent and necessary prior to establishing new treatment guidelines for STEC-HUS.


Nephron | 1993

Apolipoprotein-B-Containing Lipoproteins and the Progression of Renal Insufficiency

Ola Samuelsson; Mattias Aurell; Carolyn Knight-Gibson; Petar Alaupovic; Per-Ola Attman

Hyperlipidemia is associated with accelerated glomerular sclerosis in experimental renal insufficiency. To investigate whether the dyslipoproteinemia seen in human renal failure also influences the future course of renal insufficiency, we have correlated plasma levels of lipids and apolipoproteins at start of follow-up with the subsequent change in renal function in 34 adult patients with chronic renal disease. Nineteen patients had primary renal disease, and 15 patients had diabetic nephropathy. Except for antihypertensive therapy no specific treatment to modify the progression of the disease was given during the follow-up. The rate of progression was determined by repeated measurements of the glomerular filtration rate (GFR). The time of follow-up ranged from 12 to 91 months with an average of 39.7 +/- 16.7 months. The mean initial GFR was 34.7 +/- 13.9 ml/min x 1.73 m2 body surface area and the average decline in renal function was -0.27 +/- 0.26 ml/min/month. The entry levels of triglycerides (TG; p = 0.04), very-low-density lipoprotein cholesterol (p = 0.03), apolipoprotein-B (ApoB; p = 0.008) and systolic blood pressure (SBP; p = 0.04) were significantly correlated with the rate of progression. Among lipoprotein variables, ApoB showed the strongest correlation with the decline in GFR. Patients with a progressive course of their disease also tended to have initially higher levels of total cholesterol (TC) and low-density lipoprotein cholesterol (NS), whereas the initial plasma concentration of high-density lipoprotein cholesterol did not show an association with the progression of renal insufficiency.(ABSTRACT TRUNCATED AT 250 WORDS)


Hypertension | 2004

Impaired Endothelial Release of Tissue-Type Plasminogen Activator in Patients With Chronic Kidney Disease and Hypertension

Thórdís Hrafnkelsdóttir; Pia Ottosson; Thorarinn Gudnason; Ola Samuelsson; Sverker Jern

We have shown that the capacity for local release of tissue-type plasminogen activator (tPA) from the vascular endothelium is impaired in patients with primary hypertension. Because this response is an important protective mechanism against intravascular clotting, we investigated whether this system is also defective in patients with advanced chronic kidney disease and hypertension. Nine nondiabetic nonsmoking men with chronic kidney disease (glomerular filtration rate 11 to 28 mL/min×1.73 m2; aged 33 to 75 years) were compared with age-matched healthy controls. Intraarterial infusions of desmopressin, methacholine, and sodium nitroprusside were given locally in the brachial artery. Forearm blood flow was measured by venous occlusion plethysmography and blood collected repeatedly during the desmopressin infusion for determination of stimulated net and total cumulated release of tPA. The maximal release rate of active tPA (P<0.05) and the capacity for acute tPA release were markedly impaired in the renal patients as compared with healthy subjects (ANOVA, P=0.013). Accordingly, the accumulated release of tPA was 1905 (SEM 366) and 3387 (718) ng/L tissue, respectively (P<0.05). However, there were no significant differences in vasodilator responses between the groups. Thus, patients with advanced chronic kidney disease and hypertension have a markedly impaired capacity for acute release of tissue plasminogen activator, despite preserved endothelium-dependent vasodilation. This defect may contribute to a defective local defense against arterial thrombosis.


Clinical Pharmacokinectics | 2003

Influence of severe renal impairment on the pharmacokinetics and pharmacodynamics of oral ximelagatran and subcutaneous melagatran.

Ulf G. Eriksson; Susanne Johansson; Per-Ola Attman; Henrik Mulec; Lars Frison; Gunnar Fager; Ola Samuelsson

AbstractBackground: Ximelagatran is an oral direct thrombin inhibitor currently in clinical development as an anticoagulant for the prevention and treatment of thromboembolic disease. After oral administration, ximelagatran is rapidly absorbed and bioconverted to its active form, melagatran. Objective: To investigate the effect of severe renal impairment on the pharmacokinetics and pharmacodynamics of melagatran following administration of subcutaneous melagatran and oral ximelagatran. Study design: This was a nonblinded randomised crossover study with 2 study days, separated by a washout period of 1–3 weeks. Twelve volunteers with severe renal impairment and 12 controls with normal renal function were included, with median (range) glomerular filtration rates (GFR) of 13 (5–24) and 86 (70–105) mL/min, respectively. All volunteers received, in a randomised sequence, a 3mg subcutaneous injection of melagatran and a 24mg immediate-release tablet of ximelagatran. Blood samples were collected up to 12 and 14 hours after administration of the subcutaneous and oral doses, respectively, for determination of melagatran plasma concentrations and the activated partial thromboplastin time (APTT), an ex vivo measurement of coagulation time. Urine was collected for 24 hours after each dose for determination of melagatran concentration. Results: For the volunteers with severe renal impairment, the area under the plasma concentration-time curve (AUC) and the half-life of melagatran were significantly higher than in the control group with normal renal function. Least-squares mean estimates of the ratios of the mean AUC for volunteers with severe renal impairment and controls (95% confidence intervals) were 4.03 (3.29–4.93) after subcutaneous melagatran and 5.33 (3.76–7.56) after oral ximelagatran. This result was related to the decreased renal clearance (CLr) of melagatran, which was linearly correlated with GFR. In the severe renal impairment and control groups, respectively, the mean CLr of melagatran was 12.5 and 81.3 mL/ min after subcutaneous administration of melagatran and 14.3 and 107 mL/min after oral administration of ximelagatran. There was a nonlinear relationship between the APTT ratio (postdose/predose APTT value) and melagatran plasma concentration. A statistically significant higher slope of the concentration-effect relationship, described by linear regression of the APTT ratio versus the square root of melagatran plasma concentrations, was estimated for the group with severe renal impairment compared to the control group; however, the increase in slope was minor and the estimated differences in APTT ratio between the groups in the studied concentration range was less than 10% and not considered clincially relevant. Ximelagatran and melagatran were well tolerated in both groups. Conclusions: After administration of subcutaneous melagatran and oral ximelagatran, subjects with severe renal impairment had significantly higher melagatran exposure and longer half-life because of lower CLr of melagatran compared with the control group with normal renal function, suggesting that a decrease in dose and/or an increase in the administration interval in patients with severe renal impairment would be appropriate.


Xenotransplantation | 2006

ABO‐incompatible live donor renal transplantation using blood group A/B carbohydrate antigen immunoadsorption and anti‐CD20 antibody treatment

Gunnela Nordén; David Briggs; Paul Cockwell; Graham Lipkin; L. Mjörnstedt; Johan Mölne; Andrew Ready; Lennart Rydberg; Ola Samuelsson; Christian Svalander; Michael E. Breimer

Abstract: Background: Blood group ABO‐incompatible live donor (LD) renal transplantation may provide a significant source of organs. We report the results of our first 14 cases of ABO‐incompatible LD renal transplantation using specific anti‐A/B antibody (Ab) immunoadsorption (IA) and anti‐CD20 monoclonal Ab (mAb) treatment.


British Journal of Clinical Pharmacology | 2014

Medication reviews for nursing home residents to reduce mortality and hospitalization: systematic review and meta-analysis

Susanna M. Wallerstedt; Jenny M. Kindblom; Karin Nylén; Ola Samuelsson; Annika Strandell

Medication reviews by a third party have been introduced as a method to improve drug treatment in older people. We assessed whether this intervention reduces mortality and hospitalization for nursing home residents.

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Petar Alaupovic

Oklahoma Medical Research Foundation

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Carolyn Knight-Gibson

Oklahoma Medical Research Foundation

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Per-Ola Attman

Oklahoma Medical Research Foundation

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Per-Ola Attman

Oklahoma Medical Research Foundation

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Ann-Cathrine Johansson

Sahlgrenska University Hospital

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Annika Strandell

Sahlgrenska University Hospital

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Lars Weiss

Fresenius Medical Care

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