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J Sivenius

Publications and source records attributed to J Sivenius.

At least 73 records · Page 4Linked to original sources
PubMed1996

Ten-year trends in stroke incidence and mortality in the FINMONICA Stroke Study.

BACKGROUND AND PURPOSE: The trends in stroke incidence reported so far have not been entirely consistent, although declining trends in mortality from stroke have been reported from a number of studies around the world. This study aims to evaluate the 10-year trends (from 1983 through 1992) in incidence, attack rate, and mortality of stroke in the Finnish population. METHODS: A population-based stroke register was set up in the early 1980s to collect data on all suspected events of acute stroke that occurred in the population aged 25 to 74 years permanently residing in three geographic areas of Finland: the provinces of Kuopio and North Karelia in eastern Finland and the Turku-Loimaa area in southwestern Finland. Trends in age-standardized attack rates, incidence, and mortality were calculated for the period studied. RESULTS: During the 10-year study period, 11 392 acute stroke events occurred in the monitored populations. A statistically significant decline was observed in the pooled FINMONICA data, both in the incidence of stroke (-1.7% with 95% confidence interval [CI], -3.0% to -0.5% per year in men; -2.2% with 95% CI, -3.6% to -0.7% per year in women) and in mortality from stroke (-5.2% with 95% CI, -8.2% to -2.2% per year; -4.7% with 95% CI, -8.2% to -1.2% per year). The attack rate of stroke also declined significantly in both sexes. When the areas were considered separately, the declining trends were observed within each area. The decline in incidence of stroke was, however, statistically significant only among men and women in Kuopio and among women in Turku/Loimaa. Mortality declined significantly in all three areas among men but among women only in Kuopio. The incidence to mortality rate ratio increased during the study period, indicating a steeper fall in mortality than in incidence. CONCLUSIONS: A substantial decline in both stroke incidence and mortality was observed in the adult and elderly population in the FINMONICA study areas. Part but not all of the decline in stroke mortality, observed also in the official mortality statistics, can be attributed to the decline in stroke incidence during this 10-year period.

Adult↗
PubMed1995

The effects of NMDA receptor antagonists at anticonvulsive doses on the performance of rats in the water maze task.

In the present study we investigated the effects of two competitive NMDA receptor antagonists, CGP 37849 (DL-(E)-2-amino-4-methyl-phosphono-3-pentonoic acid) and CGP 39551 (carboxyethyl ester of CGP 37849) as well as MK-801 ((+)-5-methyl-10,11-dihydro-5H-dibenz(a,d)cycloheptene-5,10-imine hydrogen maleate), a non-competitive antagonist, administered systemically before training, on the acquisition of a water maze task used to assess spatial learning and memory in rats. The competitive NMDA receptor antagonists dose dependently impaired water maze acquisition (increased escape distance), but did not significantly affect swimming speed in rats. MK-801 induced clear behavioral effects and impaired the acquisition of the water maze task. However, as training advanced drug-treated rats did show a decrease in distance swam per trial before encountering the platform in the water pool. This suggests that drug treatments did not abolish learning. When the anticonvulsive properties of the drugs were determined, MK-801 did not show any protection in the maximal electroshock (MES) test at doses already impairing the acquisition of the water maze task while the two competitive NMDA receptor antagonists protected the rats against seizures at doses not impairing acquisition. This result suggests a wider therapeutic range for CGP 39551 and especially for CGP 37849 than for MK-801 in the treatment of epilepsy.

2-Amino-5-phosphonovalerate↗
PubMed1994

Long-term study with gabapentin in patients with drug-resistant epileptic seizures.

OBJECTIVE: To study the efficacy and safety of gabapentin in long-term treatment. DESIGN: A 4-year follow-up study of 25 patients with visits at 3-month intervals. SETTING: The patients were followed up in the outpatient unit of the University Hospital of Kuopio (Finland). PATIENTS: We treated 25 patients with drug-resistant complex partial seizures and secondarily generalized seizures in an open-label long-term study, using gabapentin as an additional means of therapy after a 3-month double-blind, placebo-controlled phase. Thirteen patients showed no benefit from gabapentin; the study medication was discontinued after 4 to 6 months of treatment. Of the 12 patients who responded enough to continue treatment, five were withdrawn due to different reasons, one because of loss of response. MAIN OUTCOME MEASURES: The number of patients receiving the study drug in the follow-up and reduction of seizure frequency from baseline level as analyzed by the Wilcoxon test. RESULTS: Seven patients received gabapentin therapy for more than 4 years. The median follow-up time was 54 months. There was a significant reduction in seizure frequency throughout the follow-up period. Five of seven patients had a greater than 50% seizure frequency reduction at 4 years, representing 20% of the 25 patients who entered the study. CONCLUSIONS: Gabapentin possesses good efficacy in long-term treatment of patients with partial and secondarily generalized epileptic seizures. It is safe to use, and it is fairly well tolerated even in long-term treatment.

Acetates↗
PubMed1994

Decrease in brain choline-containing compounds following a short period of global ischemia in gerbils as detected by 1H NMR spectroscopy in vivo.

Cerebral metabolism was studied in the postischaemic gerbil brain using surface coil 31P and 1H NMR spectroscopy. The ratio of choline-containing compounds (Cho) to total creatine (Cr) in the brain decreased from 0.46 +/- 0.02 to 0.32 +/- 0.02 by the fifth day following exposure to 5 min of global ischaemia and it remained at this low level for at least 19 days. The amounts of cerebral Cho as quantified by 1H NMR in vivo were 1.70 +/- 0.15 and 1.09 +/- 0.22 mmol/kg in control and postischaemic animals, respectively. The T2 of Cho was longer in the postischaemic cerebral cortex than in the control one. N-acetyl aspartate (NAA) as determined by 1H NMR in vivo did not differ in the two animal groups. High-resolution 1H NMR of acid-extracted brain cortices showed a decrease in total Cho (glycerophosphocholine, phosphocholine and choline) by 31%, but no changes in NAA, total creatine, taurine and myo-inositol, in the brain cortex seven days postischaemia relative to control animals. The decrease in acid extractable Cho was mainly due to the drop in glycerophosphocholine concentration. 31P NMR indicated normal energy state and phosphomonoester/phosphocreatine (PCr) and phosphodiester/PCr ratios in the in vivo brain 7 days postischaemia. Silver impregnation did not reveal neuronal degeneration but immunohistochemical staining showed a number of glial fibrillary acidic protein expressing astrocytes as indicators of reactive gliosis in the postischaemic cerebral cortex. These data show, for the first time, that a 1H NMR decrease in Cho metabolites takes place as a consequence of brief ischaemic episode even in the absence of obvious neuronal degeneration.

Animals↗
PubMed1994

Declining trends in incidence, case-fatality and mortality of stroke in three geographic areas of Finland during 1983-1989. Results from the FINMONICA stroke register.

Stroke mortality has decreased during the last decade in many industrialized countries, but there has been no clear evidence for a decline in the incidence of stroke. The present study analyzes the trends in the incidence, mortality and case-fatality of stroke in Finland from 1983 to 1989. We used data from the FINMONICA stroke register, a community based register collecting information on all suspected stroke cases aged 25-74 in three geographical areas of Finland. Annual attack rate, incidence, mortality and case-fatality rates were calculated for all strokes and for different subcategories of stroke. A linear regression model was applied to calculate the yearly trends of these rates. In men, the attack rate of stroke was 336/100,000 in 1983 and 310/100,000 in 1989 (-8% during the observation period); incidence declined from 269/100,000 in 1983 to 236/100,000 in 1989 (-12%); mortality declined from 82/100,000 to 64/100,000 (-22%), and case-fatality declined from 25% to 21% (-18%). Also among women similar declining trends were observed (-11%, -13%, -16%, and -10% respectively), but they were not statistically significant. In both incidence and mortality of stroke, the decline was seen in all age groups. Incidence and mortality of cerebral infarction declined similarly to all strokes. A large fall in the incidence (-24% in both men and women) and mortality (-38% in men and -27% in women) of subarachnoid haemorrhage was also observed. An increasing trend, although not significant, was instead observed for cerebral haemorrhage. First stroke and especially first cerebral infarction contributed most to the decline in case-fatality. The availability of computerized brain tomography improved from 18% in 1983 to 60% in 1989. We observed a fall in the incidence, mortality, and case-fatality of stroke during 1983-1989. Among the subtypes of stroke, cerebral infarction contributed most to the decline, but the data suggested also a declining trend in the incidence and mortality of subarachnoid haemorrhage, observed now for the first time in Finland since the 1960s. The fall in the incidence of stroke was not as steep during the 1980s as it was during the 1970s; Finland is anyhow the only European country which has reported a decreasing trend in stroke incidence during the 1980s. We need now to investigate how much the decline in the classical risk factors for stroke observed in Finland during the last two decades predicts the observed trends.

Adult↗
PubMed1994

Stroke incidence and case fatality in Finland and in Akita, Japan: a comparative study.

The incidence and case fatality of stroke from 1983 to 1985 from the community-based stroke register of the FINMONICA study in Finland were compared with the corresponding rates in the hospital-based register of Akita in Japan collected during 1984-1986. The comparability of the two registers was assessed, and case fatality was compared only in hospitalized cases. In Akita, the age-standardized incidence of cerebral haemorrhage in people aged 25-74 was twice that in FINMONICA, while the reverse was true for incidence of cerebral infarction. Case fatality from stroke within 48 h of onset was higher in FINMONICA than in Akita in each stroke subtype. The incidence and mortality of subarachnoid haemorrhage were similar in the two populations. The differences in early case fatality are probably due to dissimilarities in the severity of the stroke attacks rather than discrepancies in early treatment. Coding practices and also a more unlikely selection bias due to the differential use of computerized brain tomography in the two countries may play a role in differences in incidence and case fatality between these two countries.

Adult↗
PubMed1993

Elevated seizure threshold and impaired spatial learning in transgenic mice with putrescine overproduction in the brain.

We have studied the role of putrescine by using transgenic mouse lines overexpressing the human ornithine decarboxylase gene in most of their tissues. The aberrant expression of the transgene is most strikingly manifested in the brain, leading to an increase of up to 20-fold in putrescine content. We report that the transgenic mice with grossly elevated putrescine in all brain regions analysed (cortex, striatum, hippocampus and cerebellum) showed a significantly elevated seizure threshold to chemical and electrical stimuli, and impaired performance in spatial learning and memory tests. The view that putrescine may be primarily responsible for these changes was supported by the fact that the concentrations of the major neurotransmitter amino acids, glutamate and GABA in the brain, were not changed in the transgenic animals, and by the finding that a further increase in brain putrescine, achieved by inhibition of the catabolism of L-ornithine, appeared to provide additional protection against electroshock-induced seizures. These results suggest that the commonly observed increase in ornithine decarboxylase activity and the massive increase in brain putrescine in connection with neuron damage is a neuroprotective measure rather than a cause of the damage.

Animals↗
PubMed1993

Antiplatelet therapy is effective in primary prevention of myocardial infarction in patients with a previous cerebrovascular ischemic event.

OBJECTIVE: A secondary subgroup analysis of the European Stroke Prevention Study of the effect of antiplatelet medication on the risk of myocardial infarction. DESIGN AND SETTING: A randomized, double-blind placebo-controlled study with two parallel treatment groups (dipyridamole plus aspirin and placebo). Sixteen centers from six countries participated in the study. PATIENTS: A total of 2500 patients who had had one or more transient ischemic attacks or cerebral infarctions participated. INTERVENTION: Combination therapy with dipyridamole (75 mg three times a day) and aspirin (330 mg three times a day) was compared with placebo during 24 months' follow-up. OUTCOME MEASURES: Prevention of fatal and nonfatal myocardial infarction. RESULTS: A total of 105 myocardial infarctions occurred in the intention-to-treat analysis and 76 occurred in the explanatory analysis. The overall risk reduction of myocardial infarction with the study drugs was approximately 40% in both statistical analyses, but the result was statistically significant only in the intention-to-treat analysis. Therapeutic efficacy was better among male patients, patients younger than 65 years, and patients with hypertension. CONCLUSION: Combination therapy with dipyridamole and aspirin reduces not only the risk of cerebrovascular ischemic events but also the risk of myocardial infarction.

Aged↗
PubMed1993

European Stroke Prevention Study (ESPS): antithrombotic therapy is also effective in the elderly.

The ESPS was a multicenter study comparing the effect of the combination of dipyridamole 75 mg and acetylsalicylic acid 330 mg t.i.d. to placebo in 2500 patients (intention-to-treat analysis) and 1861 patients (explanatory analysis) in the secondary prevention of stroke or death after one or more attacks of TIA, RIND or stroke of atherothrombotic origin. End-point reduction was evaluated in two age groups, those not older than 65 years (1358 patients) and those who were older than 65 years (1142 patients). End-point reduction was significantly greater in patients with active therapy than in the placebo group in both age groups. Subgroup analyses with stroke as an end-point indicated that younger patients with TIA (< or = 65 years) had lower risk of stroke than those > 65 years or patients with stroke. The overall risk reduction was best in TIA patients > 65 years of age. The risk reduction with study medication was 40-50% in both sexes and in both age groups. Thus, age of the patient does not influence the efficacy of antithrombotic therapy. However, since these results are obtained from a secondary analysis of a subgroup of patients, the results may need confirmation by further studies.

Actuarial Analysis↗
PubMed1993

Stroke mortality and case-fatality rates in three geographic areas of Finland from 1983 to 1986.

BACKGROUND AND PURPOSE: Our aim was to describe the mortality and early case-fatality rates of stroke in three geographic areas of Finland during 1983 to 1986 by means of a community-based stroke register and to estimate the accuracy of registration of stroke deaths in the official statistics compared with the FINMONICA stroke register. METHODS: Annual and average mortality and case-fatality rates of stroke were derived from data collected in the FINMONICA stroke register during 1983 to 1986. Age-specific and age-standardized rates were calculated for the three areas, and the results were compared with the official mortality statistics and with the case-fatality figures published previously in the literature for Finland and elsewhere. RESULTS: Mortality from stroke in the three FINMONICA areas was between 73 and 90 per 100,000 per year among men aged 25 to 74 years and between 42 and 55 per 100,000 per year among women in the same age group. Average case-fatality was similar in the three areas and globally high: 20% to 27% in men and 24% to 28% in women. Approximately half of the fatal strokes occurred within less than 2 days from the onset of the attack, and a further 25% within the first week. Hemorrhagic strokes accounted for 54% to 81% of all fatal strokes occurring in less than 2 days among men, while among women the corresponding proportions varied in the three areas between 35% and 74%. Of cerebral infarctions, approximately 28% to 37% among men and 19% to 20% among women were fatal within less than 2 days. Although the number of fatal strokes was similar in both the FINMONICA register and official mortality statistics, only 82% to 85% of the stroke cases were common in both registers; a further 13% to 14% of the cases classified as stroke deaths in the FINMONICA register could also be found in the official mortality statistics, but the underlying cause of death was something other than stroke. CONCLUSIONS: The reliability of the Finnish official mortality statistics with regard to stroke deaths is reasonably good in aggregate numbers, but at the individual level considerable discrepancies seem to occur. Mortality from stroke in Finland has not declined further after 1979 and remains high internationally. Early case-fatality of stroke also seems higher in Finland than in most other countries. We believe that both the high incidence of stroke and the severity of the attacks are contributing to mortality and case-fatality rates of stroke in Finland.

Adult↗
PubMed1992

The FINMONICA Stroke Register. Community-based stroke registration and analysis of stroke incidence in Finland, 1983-1985.

In the early 1980s, a standardized community-based stroke register was started in three geographic areas in Finland: North Karelia and Kuopio in eastern Finland and Turku/Loimaa in southwestern Finland. The results from the first 3 years, 1983-1985, confirmed the high incidence of stroke in Finland. The incidence of stroke was higher in eastern Finland than in the southwestern part of the country. The age-standardized annual incidence among men aged 25-74 years varied from 206 per 100,000 population in southwestern Finland to 322 per 100,000 population in the province of Kuopio in eastern Finland. Among women aged 25-74, incidence was 119 and 187 per 100,000 population in these two areas, respectively. The age-standardized male:female ratio in incidence was 1.7, slightly higher than that previously reported in Finland. Out of 3,574 stroke events registered, 78% were first events without a history of previous stroke. People aged 65-74 years accounted for 45% of all events among men and 62% of all events among women. The authors' experience shows that the geographic variation in stroke incidence and attack rates is difficult to assess even within a country with a relatively uniform health care system. Rigorous standardization and quality control is needed for the assessment of long-term trends; this is the primary goal of the FINMONICA Stroke Register. The findings of this study suggest that the incidence of stroke is still high in Finland, although mortality from stroke has steeply declined during the past 15-20 years. The number of stroke survivors in Finland may actually be increasing. Since the occurrence of stroke is high in Finland as compared with other countries, intensified primary and secondary prevention measures are needed to reduce it.

Adult↗
PubMed1992

Cognitive effects of oxcarbazepine and phenytoin monotherapy in newly diagnosed epilepsy: one year follow-up.

We evaluated the effect of initial oxcarbazepine (OXC) monotherapy on memory, attention and simple psychomotor speed in 14 patients; 15 patients with initial phenytoin (PHT) monotherapy served as reference patients. Neuropsychological assessments were performed before starting the treatment and after 6 and 12 months follow-up with steady-state drug treatment. Differential cognitive effects of OXC and PHT were not apparent in our study. As the efficacy of present antiepileptic drugs in adult epilepsy is analogous, the choice of drug is determined by the comparative side effects of the drugs. In the present study the number of successfully treated patients was similar in both OXC and PHT groups. As far as cognitive side effects are concerned our results revealed no evidence favoring either antiepileptic over the other.

Adult↗
PubMed1992

European stroke prevention study: effectiveness of antiplatelet therapy in diabetic patients in secondary prevention of stroke.

BACKGROUND AND PURPOSE: The European Stroke Prevention Study was a multicenter trial comparing the effect of a combination of 75 mg dipyridamole and 330 mg acetylsalicylic acid three times a day with the effect of a placebo in the prevention of stroke or death in 1,861 patients after one or more episodes of recent transient ischemic attack or cerebral infarction. METHODS: The present study represents a secondary analysis of the efficacy of study medication in diabetic (n = 216) and nondiabetic (n = 1,645) patients. RESULTS: The risk of end point events was greater in diabetic than in nondiabetic subjects. Total end point reduction in individuals receiving the combination of dipyridamole and acetylsalicylic acid was 39% in nondiabetic subjects and 23% in diabetic subjects in the explanatory analysis, and the reduction in the risk of stroke was 48% and 32%, respectively. However, a statistically significant reduction of risk was obtained only in nondiabetic subjects. CONCLUSIONS: The combination of dipyridamole and acetylsalicylic acid appeared to be more effective in nondiabetic subjects than in diabetic subjects in the prevention of death and stroke although the low number of diabetic patients may at least in part explain this result.

Aged↗
PubMed1991

The European Stroke Prevention Study (ESPS): results by arterial distribution.

The European Stroke Prevention Study was a multicenter study comparing the effect of the combination of dipyridamole, 75 mg, and acetylsalicylic acid, 330 mg, three times a day, to that of placebo in 2,500 patients in the secondary prevention of stroke or death after one or more transient ischemic attacks, reversible ischemic neurological deficits, or strokes of atherothrombotic origin. The patients with vertebrobasilar events at entry comprised one-third of the whole patient population. The overall total incidence of stroke or death (the end points) during the 2-year follow-up in the placebo group was lower in the vertebrobasilar group compared to the carotid group (14% versus 24%, respectively). The combination therapy of dipyridamole and acetylsalicylic acid caused a marked reduction in the incidence of stroke or death in patients with vertebrobasilar (51%) and carotid (30%) events. When only stroke was considered as the end point, dipyridamole and acetylsalicylic acid seemed to be more effective in reducing the risk of transient ischemic attacks than stroke, and more effective in men than in women.

Aspirin↗
PubMed1991

Treatment of epilepsy in mentally retarded patients with a slow-release carbamazepine preparation.

Pharmacokinetic properties and efficacy of a conventional (C) carbamazepine (CBZ) preparation divided into three daily doses and a slow-release CBZ preparation (SR) divided into two daily doses were evaluated in a randomized, double-blind, cross-over study. The trial started with a 8-week baseline period followed by the two treatment periods each 10 weeks long. At the end of each period, a 24-h blood sample series for determination of serum CBZ and carbamazepine-10,11-epoxide (CBZE) was collected. The occurrence of seizures was monitored day and night during the whole study period by experienced nurses. The mean age of the 20 evaluable patients was 24.9 and the duration of epilepsy 19.2 and carbamazepine treatment 7.0 years. The bioavailability of CBZ from the two preparations was similar. The mean fluctuation of serum CBZ concentration (Cmax-Cmin/Css) was 16% smaller during SR. The mean serum CBZ concentration in the morning samples was significantly (P less than 0.001) higher during SR treatment. The mean total number of seizures was approximately four per week and did not differ between the two treatments, but during the last 2 weeks of the study period the occurrence of seizures was significantly smaller during SR (P = 0.02).

Adolescent↗
PubMed1991

Antiplatelet therapy is effective in the prevention of stroke or death in women: subgroup analysis of the European Stroke Prevention Study (ESPS).

Previous stroke prevention studies have suggested that the efficacy of antiplatelet therapy may be less in women than in men. This however, could be due to the small number of women in these trials and the low incidence of cases among female subjects. The European Stroke Prevention Study was a multicenter trial comparing the effect of a combination of dipyridamole 75 mg t.i.d and acetylsalicylic acid 330 mg t.i.d. to placebo in the secondary prevention of stroke or death after one or more recent attacks of TIA (transient ischemic attack), RIND (reversible ischemic neurological deficit) or stroke of atherothrombotic origin. From the 2500 patients recruited, 1307 patients were from a single center, Kuopio, East Finland. Forty-five percent of the patients were women. The number of end-point events (stroke or death from any cause) in women was one-third lower than that in men. End-point reduction in the treatment group was about 50% in women and about 40% in men, significantly lower than in the placebo group in both sexes. Thus, in the relatively randomly selected patient population from one Finnish center, a combination of dipyridamole and acetylsalicylic acid is as effective in women as in men in the prevention of stroke or death. It is unclear, however, whether this beneficial effect in both sexes is due to aspirin only or to the combination therapy of aspirin and dipyridamole.

Aspirin↗