Biomedical subjects

A Lindgren

Publications and source records attributed to A Lindgren.

At least 19 recordsLinked to original sources

PubMed2007

Lund Stroke Register: hospitalization pattern and yield of different screening methods for first-ever stroke.

OBJECTIVES: To explore case ascertainment, hospitalization, characteristics of both hospitalized and non-hospitalized patients in a population-based group of stroke patients. MATERIALS AND METHODS: One-year screening in Lund-Orup district for first-ever strokes using multiple prospective and retrospective methods. RESULTS: A total of 456 patients with first-ever stroke (n = 412 prospective screening methods, n = 17 primary care, n = 12 hospital registers, n = 10 death register, n = 2 autopsy registers, n = 3 other). Hospitalization proportion within 14 days was 84%. Patients sent home from emergency unit (n = 36) were often males (75%), had low 28-day case-fatality (0%), and less severe strokes (median National Institute of Health Stroke Scale score 2 vs 4 for all). Patients managed solely within primary care (n = 18) were elderly (median age 89 vs 77 years for all), resided in nursing homes (86% vs 8% for all) and had high 28-day-case-fatality (61%). CONCLUSIONS: Hospitalization was lower than expected. Two main categories of patients were not hospitalized: elderly patients at nursing homes with high case-fatality and patients with mild stroke.

Adolescent↗

PubMed2006

The Swedish Malignant Middle cerebral artery Infarction Study: long-term results from a prospective study of hemicraniectomy combined with standardized neurointensive care.

OBJECTIVES: Hemicraniectomy in patients with malignant middle cerebral artery (mMCA) infarct may be life-saving. The long-term prognosis is unknown. METHODS: Patients with mMCA infarct treated with hemicraniectomy between 1998 and 2002 at three hospitals were included. The criterion for surgical intervention was if the patients deteriorated from awake to being responding to painful stimuli only. All patients were followed for at least 1 year. Outcome was defined as alive/dead, walkers/non-walkers or modified Rankin Scale (mRS) score <or=2. RESULTS: Thirty patients were included (median age at stroke onset 49 years, range 17-67 years). Fourteen patients had mMCA infarct on the left side and 16 patients on the right side. Fourteen patients had pupil dilatation before surgery. Hemicraniectomy was performed at a median of 52 h (range 13-235 h) after stroke onset. Nine patients died within 1 month after surgery because of cerebral herniation (n = 6), myocardial infarction (n = 1) or intensive care complications (n = 2). No further deaths occurred during follow-up, which was at median 3.4 years after surgery. Status for the 21 survivors at the last follow-up was: mRS 2 or less (n = 6) and mRS 3-5 (n = 15). The oldest patient with mRS 2 or less was 53 years at stroke onset. Thirteen patients (43%) could walk without substantial aid. CONCLUSION: The long-term survival after mMCA infarction treated with hemicraniectomy seems to be favourable if the patient survives the acute phase. The outcome as measured with mRS may be better among younger patients.

Acute Disease↗

PubMed2005

Prevalence and intensity of pain after stroke: a population based study focusing on patients' perspectives.

OBJECTIVE: To determine prevalence and intensity of pain after stroke, focusing on patients' perspectives. METHODS: During a one year period, 416 first-ever stroke patients were included in the population based Lund Stroke Register. After 4 and 16 months (median), 297 patients (98% of survivors) were followed up. Worst pain intensity during the previous 48 hours was assessed on a visual analogue scale (VAS), range 0 to 100: a score of 0 to 30 was defined as no or mild pain; 40 to 100 as moderate to severe pain. NIH stroke scale (NIHSS) score and HbA1c were assessed at baseline. At 16 months, screening for depression was done using the geriatric depression scale (GDS-20), and cognition with the mini-mental state examination (MMSE). Predictors of pain were determined by multivariate analyses. RESULTS: Moderate to severe pain was reported by 96 patients (32%) after four months (VAS median=60). Predictors of pain were younger age (p=0.01), female sex (p=0.006), higher NIHSS score (p<0.001), and raised HbA1c (p=0.001) at stroke onset. At 16 months, only 62 patients (21%) had moderate to severe pain, but pain intensity was more severe (median VAS score=70; p<0.016). Higher pain intensity correlated with female sex, worse GDS-20 score, better MMSE score, and raised HbA1c. Pain was persistent in 47%, disturbed sleep in 58%, and required rest for relief in 40% of patients. CONCLUSIONS: Although prevalence of pain after stroke decreased with time, after 16 months 21% had moderate to severe pain. Late pain after stroke was on average more severe, and profoundly affected the patients' wellbeing.

Adolescent↗

PubMed2005

A micellar electrokinetic capillary chromatography method for monitoring mycophenolic acid in serum of transplant recipients.

Mycophenolic acid (MPA), the active metabolite of the immunosuppressive agent mycophenolate mofetil (MMF), was for the first time quantified in the serum of transplant recipients using micellar electrokinetic capillary chromatography (MEKC). Sample preparation was carried out with solid phase extraction (SPE) using octadecyl-modified endcapped silica (C18 EC) as sorbent. Extremely varying recovery rates in preliminary experiments showed both the importance of pH monitoring during the single SPE steps and the necessity of an internal standard. MPA carboxy butyl ether (CBE), a specifically developed reference standard, was employed. Furthermore, optimisation of the MEKC parameters detection wavelength and injection time was of primary importance in order to enable the quantitation of therapeutic trough serum levels of MPA in the range lower than 5 microg x mL(-1). Under optimised conditions, a limit of quantitation of 1.0 microg x mL(-1) was achieved allowing the determination of MPA in the serum of patients.

Algorithms↗

PubMed2004

Preoperative serum levels of follicle stimulating hormone (FSH) and prognosis in invasive breast cancer.

AIMS: We investigated the association between preoperative serum levels of follicle stimulating hormone (FSH) and the prognosis in women with invasive breast cancer. METHODS: Serum levels of FSH were measured in 182 premenopausal and 581 peri- or postmenopausal women with invasive breast cancer. They were followed for a mean time of 84 months. The study endpoint was death from breast cancer (182 events). Analyses were stratified on menopausal status. RESULTS: None of the estimates showed a statistically significant result. In both pre- and postmenopausal women there was a nominally higher probability of survival with a higher FSH level. Point estimates in multivariate analysis incorporating age, tumour diameter, axillary lymph status, estrogen and progesterone receptor content and year of treatment indicated a stronger association with FSH levels in premenopausal than postmenopausal women (relative hazard 0.63 or 0.85, respectively in the highest compared with the lowest quartile). CONCLUSION: We did not find any statistically significant association between preoperative serum level of FSH and prognosis. Today, FSH is not a clinical target for intervention or a clinically useful prognostic factor and the results of clinical studies up to date can only be used for motivation of further experimental laboratory research.

Adult↗

PubMed2004

Costs of on-demand and prophylactic treatment for severe haemophilia in Norway and Sweden.

The expected annual cost (in the year 2000 prices) for a 30-year-old patient with average individual and treatment characteristics for on-demand EUR 51,832 (95% CI: 44,324-59,341) and for prophylaxis EUR 146,118 (95% CI: 129,965-162,271), was obtained from panel-data analysis of an 11-year retrospective panel of 156 patients with severe haemophilia in Norway and Sweden. Costs included haemophilia-related treatment costs within the health-care sector (factor concentrate, doctors' visits, diagnostic procedures, hospitalisation, invasive procedures, etc.) and cost for haemophilia-related resource use in other sectors (lost production, use of special equipment, adaptation of workplace and domicile, etc). Although costs of lost production, reconstructive surgery and hospitalisation were higher for on-demand, they did not balance out the higher costs of factor-concentrate consumption in prophylaxis. The cut-off risk of premature death, where on-demand and prophylaxis would have been equally costly, was 3.7 percentage units higher for on-demand than for prophylaxis. Such a great risk difference has not been reported elsewhere to our knowledge. Estimated cost-elasticities indicated that annual costs of prophylaxis would increase by approximately the same proportion as a potential increase in the price of factor concentrate and decrease less than proportionately with a reduction in prescribed dose kg(-1). For on-demand, the annual costs would increase by approximately the same proportion as an increase in the prescribed dose kg(-1).

Adult↗

PubMed2004

Willingness to pay for on-demand and prophylactic treatment for severe haemophilia in Sweden.

The objective of the present paper was to provide an estimate of the benefits of on-demand and prophylaxis treatment strategies for severe haemophilia in monetary terms. Using the contingent-valuation method, which simulates a missing market by asking people about their willingness to pay (WTP), we asked a representative sample (n = 609) of the Swedish population if they would be willing to pay a specific amount (bid) so that patients with severe haemophilia could receive on-demand treatment and another bid for prophylactic treatment. Different respondents were offered different bids and the bid vector ranged from 71 Euro cents to EUR 130. The order of the bid questions was randomized so that half of the respondents were asked first about their WTP for on-demand treatment, and then about their WTP for prophylaxis, while the order was reversed for the other half of the respondents. The mean estimated WTP (year 2002) was EUR 39 (95% CI 31-47) for on-demand and EUR 65 (95% CI 55-73) for prophylaxis. Our sensitivity analysis showed that the ranking of the two treatment alternatives was robust in that the WTP was greater for prophylaxis in all possible subsets. The point estimates of WTP varied somewhat in subsets defined by individual characteristics, but confidence intervals always overlapped that of the main results. The WTP for on-demand and prophylaxis exceeded the calculated cost of treatment per taxpayer of providing on-demand and prophylactic treatment, respectively, based on our previous results.

Adult↗

PubMed2003

Risk factors for local recurrence after breast-conserving surgery.

BACKGROUND: It is not clear whether risk factors for local recurrence after breast-conserving surgery differ in women having surgery for in situ or invasive cancer. Furthermore, the Nottingham Prognostic Index (NPI) and Nottingham Histological Grade (NHG) have been little studied as determinants of local recurrence risk. METHOD: In a case-control study (491 cases and 1098 controls) nested within a cohort of 7502 women who had surgery for in situ or invasive cancer of the breast, patient characteristics, tumour characteristics and treatment-related variables were evaluated as risk factors for local recurrence. RESULTS: Multivariate conditional logistic regression analyses showed that age below 40 years, tumour multicentricity and an unclear or unknown surgical margin were significant risk factors for local recurrence. Radiotherapy to the breast and adjuvant hormone therapy were protective. Cancer in situ was not associated with a higher risk of local recurrence than invasive cancer (odds ratio 1.0, 95 per cent confidence interval 0.8 to 1.3). NHG and NPI were not helpful in determining risk of local recurrence. CONCLUSION: Margin status, age, tumour multicentricity, and use of radiotherapy and adjuvant hormone therapy were important determinants of risk of local recurrence. With the exception of surgical margin, variables related to the quality of surgical management did not predict risk of local recurrence.

Adult↗

PubMed2003

On-demand vs. prophylactic treatment for severe haemophilia in Norway and Sweden: differences in treatment characteristics and outcome.

Using an 11-year panel of 156 Norwegian and Swedish patients with severe haemophilia, and including retrospective case-book data from birth, we compared the differences in the haemophilia-related resource use between on-demand and prophylactic treatment. Patients treated on-demand had more surgery (arthrodeses, prostheses implantations and synovectomies) and more days lost from work. Median annual factor-concentrate consumption among adults (18+) was 211,000 IU [interquartile range (IQR) 154,000-268,000] or 3,024 IU kg-1 year(-1) for patients on prophylactic treatment and 55,000 IU (IQR 28,000-91,000) for on-demand patients (780 IU kg(-1) year(-1)). This was partly explained by the fact that the median dose per kg body weight was twice as great 28, (IQR 24-32) for prophylaxis compared with 14 (IQR 12-16) for on-demand. Prescribed dose per kg body weight was found to be an important factor explaining the variation in total annual factor-concentrate consumption per patient for both types of treatment. Other variables included in the panel-data regression analysis were the number of weeks on secondary prophylaxis for on-demand patients and age, body weight and type of haemophilia for children (0-17 years) on prophylaxis. Differences were consistently substantial and will affect both costs and benefits of the two treatment strategies.

Absenteeism↗

PubMed2002

Carotid artery stenosis: contrast-enhanced MR angiography with two different scan times compared with digital subtraction angiography.

Contrast enhanced magnetic resonance angiography (CE MRA) is a non-invasive alternative to conventional digital subtraction angiography (DSA). CE MRA is increasingly used as a complement to Duplex in the preoperative assessment of carotid artery stenosis. The purpose of this study was to determine if CE MRA could replace preoperative DSA. CE MRA with a scan time of 10 or 28 s was performed in 24 consecutive patients who were scheduled for preoperative DSA because of Duplex-verified severe carotid artery stenosis. Two neuroradiologists measured the degree of stenosis with three different methods, and the image quality was evaluated. DSA was used as the gold standard. For detection of severe stenosis (N. American symptomatic carotid endarterectomy trial (NASCET) > or =70%; European symptomatic carotid endarterectomy trial (ECST) > or =80%; common carotid artery method (CCAM) > or =80%), the sensitivity of CE MRA maximum intensity projection (MIP) compared with DSA was 82%-100 %, the specificity was 74%-93% and the accuracy was 77%-90%. The inter-observer agreement was higher, the image quality was better and the intracranial main arteries were better visualized with the 28 s than with the 10 s scan time. The enhancement of the jugular veins seen in 17% of the 10 s scans and in 58% of the patients with the 28 s scans did not interfere with the evaluation of the carotid arteries. CE MRA, preferably with a scan time of 28 s, can replace DSA in the preoperative assessment of most patients with carotid artery stenosis.

Aged↗

PubMed2002

Discounting and clinical decision making: physicians, patients, the general public, and the management of asymptomatic abdominal aortic aneurysms.

Clinical decisions often entail in intertemporal trade-off. Moreover, they often involve physicians of different specialities. In an experiment dealing with the management of small asymptomatic abdominal aortic aneurysms (a clinically relevant problem) we find that specialists in internal medicine exhibit higher implicit discount rates than vascular surgeons, general practitioners, and actual and prospective patients. Several personal characteristics expected to be directly related to pure time-preference and risk aversion (gender, smoking habits, age, place of employment) have the hypothesised effects. Additionally, financial incentives appear to affect the estimated implicit discount rates of physicians, but are unlikely to have caused the inter-group differences. Differences in discount rates could lead to variations in clinical practice, which may conflict with equality of treatment or equal access to health care.

Aged↗

PubMed2002

Characterization of inhibitors to FVIII with an ELISA in congenital and acquired haemophilia A.

Different methods can be used for the detection and quantification of inhibitors or antibodies to coagulation factor VIII (FVIII). Traditionally, clotting assays have been used, in particular the Bethesda assay. These assays have, however, several shortcomings, due to the complex reaction kinetics of some inhibitors and a low sensitivity to low-titre antibodies. In addition, a universal FVIII inhibitor standard is lacking. Furthermore, clotting assays do not detect noninhibitory antibodies. Use of ELISAs has been described and FVIII from various commercially available FVIII concentrates has been used as target antigen in the assays. In the present study, we systematically explored the influence of different FVIII concentrates on the performance of an ELISA for detection of FVIII antibodies. The described ELISA was also used for further characterization of FVIII inhibitors in patients with acquired and congenital haemophilia A. We found that the source of FVIII had a substantial impact on the frequency of antibody detection. Albumin-free recombinant FVIII as target antigen gave the highest sensitivity for the assay, whereas plasma-derived concentrates containing a high level of von Willebrand factor (vWF) gave the lowest sensitivity. Presumably vWF interferes with the binding of antibodies to FVIII. We suggest that albumin-free recombinant FVIII should be used as target antigen when ELISAs are used for detection of FVIII antibodies.

Antibodies↗

PubMed2002

Demographic transition of the Swedish cystic fibrosis community--results of modern care.

Assessing the results of modern cystic fibrosis (CF)-care and estimating the future population and its demography is important to evaluate the treatment regimens and to calculate the future needs of health-care resources. This paper updates previous incidence calculations. It assesses the results of modern CF-care in terms of survival and changing demography in Sweden. The incidence of CF in Sweden was calculated as 1/5600 live-births. Of the CF-population alive in 1999, 45% were > or = 18 years old. The mean annual mortality rate since 1991 was 0.9% (+/-0.4) and the median age at death 26 years (range 0-72). Of those born > or = 1991, 95% were estimated to survive their 25th birthday. The incidence of CF in Sweden is low. Modern CF-care in Sweden shows good results. The CF-population is growing rapidly and the adult part of the population will soon be larger than the paediatric. Continuously adapted resources are required to assure the future treatment quality especially for the growing adult CF-population.

Adolescent↗

PubMed2002

Elevated serum methylmalonic acid. How much comes from cobalamin deficiency and how much comes from the kidneys?

Serum methylmalonic acid (S-MMA) as a sensitive indicator of cobalamin deficiency was introduced more than 10 years ago. The use of this method for identifying patients with cobalamin deficiency reflects much higher prevalence figures than was previously thought. In this review, all major studies on the subject are analysed. The least common denominator that could explain the probably overrated prevalence figures is the deteriorated renal function accepted for inclusion in virtually all the studies. A strong association between S-MMA and S-creatinine, even within the normal range for creatinine. has become increasingly apparent. At present, it is impossible to estimate how much of elevated S-MMA comes from impaired renal function and how much comes from impaired cobalamin metabolism. Thus, the use of S-MMA as the sole indicator of cobalamin deficiency cannot be recommended.

Humans↗

PubMed2001

Persistent high signal on diffusion-weighted MRI in the late stages of small cortical and lacunar ischaemic lesions.

Diffusion-weighted imaging (DWI) is very sensitive to early brain infarcts. However, the late stages have been insufficiently studied. Infarcts in small vessel disease are often multiple and of different ages, and differentiation between new and old lesions might be difficult. We have therefore studied the change with time in DWI of small (< 3 ml) ischaemic lesions. We imaged 21 patients with an acute lacunar syndrome and a lesion visible on early DWI. They all had three MRI examinations 12-58 h (early), 7-16 and 54-144 days after the onset of stroke; 10 patients with high DWI signal on the third examination had a fourth examination 12-28 months after the stroke. MRI was performed at 1.5 T, using echo-planar DWI with 7 b-values from 0 to 1200 x 10(6) s/m2 and conventional T2-weighted imaging. After 7-16 days 18 of 21 lesions gave high signal on DWI, and 12/16 measurable lesions had a decreased apparent diffusion coefficient (ADC). After 54-144 days ten lesions still gave high DWI signal and two still had an ADC below normal. On the fourth examination there was no remaining high DWI signal and all ADC were higher than normal.

Brain↗

PubMed2001

The value of b required to avoid T2 shine-through from old lucunar infarcts in diffusion-weighted imaging.

Multiple small infarcts of different ages are common in small-vessel disease. Diffusion-weighted imaging (DWI) is a powerful method for discriminating new from chronic lesions. This can be done on the diffusion-weighted images provided that b is sufficiently high. Our purpose was to determine that critical value of b. We reviewed DWI from a previous study of acute, mainly lacunar strokes, and selected 18 old lacunar infarcts, well defined on uncoded images with b 0 s/m2 (i. e., T2-weighted images) but invisible on DWI with b 1,200 x 10(6) s/m2. We used a 1.5 tesla imager and single-shot echo-planar technique. We had seven separate acquisitions with echo time 123 ms and b in steps between 0 and 1,200 x 10(6) s/m2. Two neuroradiologists blinded to the selection of lesions carried out two different lesion-detection procedures, thereby testing each lesion four times, giving a total of 72 tests of b values. The results were consistent, indicating a level for detection of 800 x 10(6) s/m2 in two tests, 400-600 x 10(6) s/m2 in 65 tests and at lower values in the remainder. For imagers up to 1.5 tesla, at long repetition times and an echo time up to 120 ms T2-shine through of old lacunar infarcts can be avoided using b of 1,000 x 10(6) s/m2.

Brain↗

PubMed2001

Spectroelectrochemical study of cellobiose dehydrogenase and diaphorase in a thiol-modified gold capillary in the absence of mediators.

A spectroelectrochemical cell was constructed from a gold capillary with 200 microm inner diameter as a working electrode. This allowed spectroelectrochemical study of liquid samples with available volumes less than 5 microl. The optical measurements were accomplished with an optical fibre spectrometer. The optical path of the cell was about 1 cm. To facilitate electrochemistry of biomolecules, the surface of the gold capillary was modified with thiols. The formal potential, E degrees', of the heme in cellobiose dehydrogenase (CDH) from Phanerochaete chrysosporium was determined by spectroelectrochemistry in the absence of redox mediators. The number of electrons per redox conversion of heme in CDH was found to be equal to 0.98 + 0.04 corresponding well to a theoretical value representing the redox reaction Fe3+ + e-= Fe2+. Similar spectroelectrochemical experiments with diaphorase from Bacillus stearothermophilus showed the redox conversion of the flavin mononucleotide in diaphorase in the absence of external redox mediators.

Carbohydrate Dehydrogenases↗

PubMed2001

Mammographic finding as predictor of survival in 1-9 mm invasive breast cancers. worse prognosis for cases presenting as calcifications alone.

PURPOSE: To investigate breast cancer survival in small invasive breast cancers in relation to mammographic findings. MATERIALS AND METHODS: We investigated a consecutive series of 96 cases of 1-9mm small invasive breast cancers diagnosed 1988-1994. Median follow-up of the survivors was 7 years (range: 4.5-10.5). Mammographic findings were classified into rounded masses, spiculated masses, calcifications (casting or pleomorphic) and masses combined with calcifications. Lymph node status and histological malignancy grade were also evaluated. Eight year survival rate in breast cancer was estimated with the Kaplan-Meier method and risk of death with proportional-hazards regression. RESULTS: 6/96 women died from breast cancer. 3/14 had calcifications alone, 2/56 with spiculated masses, 1/12 with rounded masses. 5/78 who died were node-negative cancers and 1/4 was node-positive. The survival rate for the whole group was 93%: 77% for the calcifications alone group, 95% for spiculated masses and 91% for rounded masses. The survival rate for the node-negative cancers was 92% compared to 75% for node-positive cancers. Calcifications alone (p = 0.01) and node positivity (p =0.03) had each independent significant higher risk of death taking finding, node status and grade into account. CONCLUSION: Small invasive breast cancers mammographically presenting as casting or pleomorphic calcifications alone have a significantly worse prognosis than other types.

Adult↗