Determinants of long-term mortality after stroke

Risk factors of death for a population of 409 patients with well-defined cerebrovascular disease (patients with subarachnoidal hemorrhage excluded) admitted to the Stroke Unit were studied with the aid of the life table technique, log rank test, and multivariate analysis with BMDP's program for regression on the survival curves with Cox's proportional hazard model. The estimated proportion of survivors was 77% after three months, 69% after one year, and 32% after five years. Patients with intracerebral hemorrhage and embolic cerebral infarction had the worst outcome. Impaired consciousness on admission was the most important risk factor of death followed by high age, previous cardiac failure, diabetes mellitus and male sex.

Diagnostic criteria and quality control of the registration of stroke events in the MONICA project

Stroke events are being registered in 27 of the MONICA collaborating centres. Coding of test cases has shown the greatest discrepancies in coding of the type of stroke (different pathoanatomical diagnoses) and of the diagnostic category (whether a definite stroke has occurred or not), 23% and 14% discrepancies respectively. A check for completeness of stroke registration at the Northern Sweden MONICA Center showed that more than 91% of the events were retrieved by routine registration procedures. Measures to reduce the discrepancies in coding between centres and to check for completeness of data are suggested. In many centres, the number of stroke events below 65 years of age is too small to permit meaningful analyses. By including also stroke events in the 65-74 year age range, the number of fatal events in the Northern Sweden MONICA area increased by 195% and non-fatal events by 149%. Many other MONICA centres have also extended their upper age limit for the registration of stroke events, thus improving the preconditions for statistical evaluations of the long-term changes in stroke incidence.

Hyperosmolar non-ketotic coma in diabetic stroke patients

Hyperosmolar non-ketotic coma in diabetes is a life-threatening condition. We describe three patients, aged 59-67 years, who developed hyperosmolar coma during the first ten days after admission for stroke. Common to all three were normal plasma osmolality and slightly elevated plasma creatinine levels on admission, treatment with diuretics, parenteral dextrose administration before and low urinary glucose output during the coma. In the five days preceding the coma, total fluid deficits were 3.8, 6.5 and 9.4 1, respectively. In one patient the rate of glucose delivery had clearly exceeded utilization during adequate insulinization, in another a marked reduction in urinary glucose output preceded extreme hyperglycaemia and coma. Two of the three patients died, both from extensive thrombus formation in cerebral arteries and multiple emboli to the lungs. We conclude that enhanced endogenous glucose production and reduced renal clearance of glucose may contribute to precipitate hyperosmolar non-ketotic coma. A close monitoring of fluid and dextrose administration seems mandatory in diabetic stroke patients, in particular if renal function is impaired or if diuretics are given. Insulin treatment should be considered in all diabetic patients during the first days after a stroke.

Diuretic treatment and magnesium losses

Therapy with most kinds of diuretics causes increased urinary excretion of both potassium and magnesium and after long term treatment the skeletal muscle content of these ions is reduced. Magnesium is known activator of Na-K-ATP:ase, which provides the energy for the sodium-potassium pump. Thus, lack of magnesium may impair the pumping of sodium out from the cell and potassium into the cell. Three studies are presented which agree with this theory. In one study the correlation between potassium in serum and potassium in muscle was, among other factors, found to be dependent on the content of muscle magnesium. In another study it was found in hypokalemic patients that muscle potassium could not be corrected by potassium supplementation if there was a concomitant magnesium deficiency. In the third study it was found that muscle potassium increased after magnesium infusion but not after potassium infusion.

Urinary zinc excretion during treatment with different diuretics

Urinary zinc excretion was studied in a randomized trial in 9 patients during treatment with bendroflumethiazide, chlorthalidone and hydrochlorothiazide and in another 9 patients during treatment with bumetanide, furosemide and triamterene. During treatment with the thiazides, the zinc concentration rose by 30% and the total amount of zinc excretion increased by 60%. In contrast, during treatment with the loop-diuretics, urine zinc concentration diminished and the total amount of zinc excretion increased much less than during therapy with the thiazides. With respect to the importance of zinc as an essential element in human metabolism and the frequency of diuretic treatment, the observed increased urinary losses of zinc deserve further attention.

Amiloride prevents thiazide-induced intracellular potassium and magnesium losses

To study the effect of a combination of amiloride, 5 mg, and hydrochlorothiazide, 50 mg (Moduretic), on plasma and skeletal muscle electrolytes in patients on long-term diuretic therapy (greater than 1 year) for arterial hypertension and/or congestive heart failure, 58 patients were recruited. Fifty-five patients completed the study, 27 controls and 28 in the treatment group. The Moduretic group demonstrated a significant increase in skeletal muscle potassium and magnesium values and a significant decrease in systolic blood pressure after 6 months on therapy. There was no significant change in these parameters in the control group. It is concluded that this combination of amiloride and hydrochlorothiazide is capable of preserving the internal and external balance of potassium and magnesium on a long-term basis in the patient categories studied.

Mortality pattern among initial survivors of acute myocardial infarction using a life-table technique

The 5-year pattern of mortality among 475 immediate survivors of acute myocardial infarction (AMI) (mean age 65 years on entry) is described by a life-table technique. The risk of death was highest during the early part of the follow-up. After 3-4 years, the prognostic influence of the AMI seemed to be overshadowed by the age effect. Special attention was paid to the incidence of sudden death, a fictive elimination of which was shown to reduce the risk of death by 9-22% during the different years of the investigation period. The absolute number of sudden deaths was highest during the early part of the follow-up period but the relative importance of this mode of death was approximately the same during the entire 5-year period after the AMI.

Relation between potassium, magnesium and cardiac arrhythmias

Magnesium may influence the incidence of cardiac arrhythmias by 1) a direct effect 2) an effect on potassium metabolism 3) an effect as a calcium blocking agent. In the event of a magnesium deficiency the cell cannot attract potassium against the transmembrane concentration gradient. The reason may be that a magnesium deficiency interferes with the function of membrane ATPase, and thus the pumping of sodium out from the cell and potassium into the cell is impaired. The interference from a magnesium deficiency on the equilibrium of potassium between the intra- and extracellular spaces may result in changes in the resting membrane potential, changes in potassium conductance across the cell membrane as well as disturbances in the repolarization phase.

Effects on muscle electrolytes of potassium and magnesium infusions, spironolactone medication and operation in a case of primary aldosteronism

Serum and muscle electrolytes were determined in a case of primary aldosteronism before and after potassium and magnesium infusions as well as spironolactone treatment and following surgery. Repeated potassium infusions resulted in a transient normalization of the muscle potassium (K/m), followed within 3-4 days by a return to the previously low K/m. Magnesium infusions did not give any increase in muscle magnesium (Mg/m). On the contrary, there was a decrease in Mg/m concomitant with a decrease in K/m. Treatment with spironolactone for one month was followed by a normalization of both serum and muscle electrolytes. Following surgery the serum potassium and K/m remained normal, but the serum magnesium (Mg/s) and Mg/m showed a decrease to subnormal values. Despite the initial findings of normal Mg/s and Mg/m as well as excretion of more than 80% of the i.v. magnesium dose, this may indicate that there was a magnesium deficiency in the skeletal pool.

The relation between extra- and intracellular electrolytes in patients with hypokalemia and/or diuretic treatment

The relation between extra- and intracellular electrolytes has been studied by means of percutaneous muscle biopsies in 107 patients with hypokalemia and/or treatment with diuretics. No relation was found between the extra- and intracellular concentrations of Na or Mg. The serum and muscle contents of K correlated weakly. The correlation coefficient tended to be stronger when S-creatinine was normal, total carbonate was between 25 and 30 mmol/l, muscle Mg content was greater than or equal to 3.95 mmol/100 g fat free dry solids, and when no treatment was given with digitalis and/or diuretics.

Arrhythmias in patients with acute cerebrovascular disease

Cardiac disease is common in patients with cerebrovascular disease (CVD) and cerebral lesions as such may influence cardiac activity and rhythm. To study the indication for continuous ECG surveillance of patients with CVD, 100 consecutive patients admitted to a medical stroke unit were investigated with 24-hour Holter recordings. The patients' mean age was 73 years and 70% of them had a history of heart disease. Twenty-three patients had chronic atrial fibrillation and 55% of the remainder showed ventricular ectopic activity. Serious ventricular arrhythmias were comparatively rare and mainly seen in association with signs of congestive heart failure and acute myocardial infarction. A prolonged Q-T interval was registered in two-thirds of the patients but there was no significant association between this finding and ventricular ectopic activity. Close observation for cardiac complications is important in patients with CVD and continuous ECG surveillance is indicated in selected high-risk patients.

Aggravation of thiamine deficiency by magnesium depletion. A case report

A patient with Crohn's disease and long-standing diarrhea resulting in a combined thiamine and magnesium deficiency is presented. Despite massive doses of thiamine i.v., the symptoms of thiamine deficiency could not be suppressed until the magnesium deficiency was corrected as well. This case report emphasizes the dependence of thiamine on magnesium for an adequate function in the body.

Zinc balance before and during treatment with bendroflumethiazide

The present study gives full balance data for zinc in two healthy individuals before and during treatment with chlorthalidone. Positive zinc balances were noted in both subjects without therapy. During chlorthalidone treatment the balances changed in a negative direction. Thus, the normal or slightly increases serum zinc values, which have been observed during diuretic treatment in spite of increased urinary losses of zinc, cannot be explained by increased zinc absorption. Depletion of zinc in tissues seems likely.

Intracellular electrolytes in cardiac failure

In congestive heart failure (CHF) there are several compensatory mechanisms operating which may influence electrolyte metabolism. The activation of the renin-angiotensin-aldosterone system causes retention of sodium (Na) and losses of potassium (K) and magnesium (Mg). The secondary hyperaldosteronism may give rise to high intracellular Na and low intracellular K through a direct permeability effect on the cell membrane. The Mg deficiency may lead to a further increase of intracellular Na and decrease of intracellular K since Mg is a necessary ion for the function of the Na-K pump. In 297 patients with diuretic treated CHF we found that 42% had hypokalemia, 37% hypomagnesemia and 12% hyponatremia. We also found that 57% had excess muscle Na, 52% had depletion of muscle K and 43% had low muscle Mg. We have also shown that the low muscle K cannot be corrected by K supplementation when there is a concomitant Mg deficiency and that Mg infusions may change the disturbed relation between extra- and intracellular electrolytes towards normal.

Salt and water balance in congestive heart failure

The majority of symptoms related to congestive heart failure (CHF) can be derived from the excessive accumulation of fluid in the body. The retention of fluid is the result of the activation of a complex system of compensatory mechanisms working on the kidneys and altering the hemodynamic situation in the body. The compensatory mechanisms are essentially the same as those activated in acute blood loss. The common denominator for CHF and acute blood loss is a decrease of the effective arterial blood volume (EABV), a parameter defined as blood volume in relation to vascular capacity. In the early stages of CHF there is an increased sympathoadrenergic tone, leading to a peripheral vasoconstriction and a decrease of blood flow to the kidneys. Due to a preferential constriction of the efferent arterioles, the filtration fraction is increased and the glomerular filtration rate remains unchanged. However, there is an increased colloid osmotic pressure and a decreased intravascular hydrostatic pressure in the peritubular capillaries. These alterations result in an increased reabsorption of sodium and water in the kidneys. Furthermore, the blood flow in the kidneys is rerouted from the cortical to the juxtamedullary nephrons, which have larger glomeruli and longer loops of Henle. This will further increase the retention of salt and water. The renin-angiotensin-aldosterone (R-A-A) system is also activated due to the decrease of EABV. Angiotensin II exerts about the same effects as norepinephrine--vasoconstriction, rerouting of blood within the kidney and preferential vasoconstriction of the efferent arterioles--all changes contributing to the retention of salt and water.(ABSTRACT TRUNCATED AT 250 WORDS)

Magnesium deficiency contributing to ventricular tachycardia. Two case reports

Two cases of ventricular tachycardia (VT), possibly caused by magnesium deficiency, are presented. Skeletal muscle biopsies and blood samples were taken before and after magnesium infusions. These infusions resulted in a significant retention of magnesium, and the VT attacks vanished permanently in one case and temporarily in the other.

The natural history of stroke in diabetic patients

A five-year follow-up of 53 diabetic patients admitted for their first stroke in 1972--73 has been performed. They were compared with two groups of 53 non-diabetic patients each with cerebrovascular disease (CVD), one randomly selected and one matched with the diabetics for age, sex and diagnosis of CVD at discharge. All patients could be traced at follow-up. The mean age at the time of first stroke was 66.5 years in male and 73.2 years in female diabetics. Manifest diabetes was diagnosed in 19% during hospitalization for stroke; of the remainder, 74% had had diabetes since less than ten years. In 85% of the diabetics there were no signs of severe angiopathy affecting eyes, kidneys or lower extremities. The majority of diabetic as well as non-diabetic CVD patients had a history of hypertension and/or heart disease. Few were overweight. Case fatality rate was significantly higher in diabetics than in non-diabetics throughout the follow-up (p less than 0.01 for diabetics vs. matched non-diabetics, p less than 0.001 for diabetics vs. randomly selected non-diabetics). The presence of heart disorder predicted mortality in the diabetic subjects. Surprisingly, hypertension diagnosed before stroke involved a more favourable long-term prognosis in all three groups (p less than 0.05). The major causes of death in diabetic CVD patients were cardiac disorders (50%) and stroke (47%). Previous investigations have identified diabetes as a risk factor for stroke. This study shows that diabetes also adversely affects the short-term as well as the long-term outcome in stroke.

Ventricular extrasystoles and intracellular electrolytes in hypokalemic patients before and after correction of the hypokalemia

Fifty-four initially hypokalemic patients, 43 of whom were on diuretic treatment, were given potassium supplementation until they showed a repeatedly normal serum potassium level. Muscle specimens obtained by percutaneous biopsy revealed that there were no concomitant increases in muscle potassium content, nor in intracellular potassium concentration, except in the very small group (6 patients) with a muscle magnesium content of greater than or equal to 3.95 mmol/100 g fat free dry solids (FFDS) and an initially lower muscle potassium content (less than or equal to 39.9 mmol/100 g FFDS). ECG, registered for 3 hours on a portable ECG tape recorder before and after correction of the serum potassium level, showed no change in the frequency of ventricular ectopic beats.

Renal excretion of electrolytes in patients on long-term diuretic therapy for arterial hypertension and/or congestive heart failure

Renal excretion, skeletal muscle content and plasma concentration of electrolytes were studied in 108 patients on long-term diuretic therapy for congestive heart failure and/or arterial hypertension. As reference populations served a group of 16 healthy volunteers and a group of 22 patients with liver cirrhosis, but not on diuretic therapy. Diuretic therapy was found to deprive the patients of their ability to conserve potassium and magnesium when there was a simultaneous cellular depletion of these ions. Magnesium excretion was found to be correlated to the skeletal muscle magnesium content. An inverted Na/K ratio in urine and a low magnesium excretion were fair indicators of cellular magnesium depletion.

Tissue zinc at autopsy--relation to medication with diuretics

Diuretic treatment has been shown to cause a substantial increase in the urinary output of zinc. However, the serum zinc levels remain normal or even raised. In the present study, tissue zinc was studied in liver, kidney and skeletal muscle tissue from 147 consecutive autopsies. In 90 of the cases heart muscle and aortic tissue were also studied. The zinc values were correlated to previous treatment with diuretics. A lower liver zinc level was observed in the group of patients who had been on diuretic treatment for more than 6 months compared to the group without treatment, the difference being highly significant. The skeletal muscle zinc was also low in the patients who had been on diuretic treatment. With regard to the metabolic functions of zinc, the tissue depletion of this element after diuretic treatment may be of clinical importance.

Plasma and skeletal muscle electrolytes in patients on long-term diuretic therapy for arterial hypertension and/or congestive heart failure

Investigations regarding plasma and skeletal muscle electrolytes were carried out in 537 patients on long-term diuretic treatment (greater than 1 year) for arterial hypertension (n = 240) and/or congestive heart failure (n = 297). In both groups there were significant decreases in both plasma and skeletal muscle K and Mg, while the muscle Na values as well as the total and extracellular water content of skeletal muscle were increased.

Serum thyroid-stimulating hormone in cerebrovascular disease

A thyrotropin-releasing hormone (TRH) test with serum thyroid-stimulating hormone (TSH) assays was performed in 22 euthyroid stroke patients without thyroid disease and the results were compared with those in 17 age-matched euthyroid controls. Basal and maximum TSH levels after TRH injection were significantly lower in the stroke group without elevation of basal serum thyroid hormone levels. There was a tendency towards an inverse relationship between TSH levels and the degree of pareses of the extremities. The test was repeated in 7 stroke patients 3-4 months after the onset of stroke with essentially the same results. The abnormal TSH parameters in stroke patients seem to be the result of the brain lesion per se.

Cardiovascular risk factors in the Northern Sweden MONICA Study

In the WHO MONICA Study, determinants and trends in cardiovascular disease are monitored during a 10-year period in 40 centers in 27 countries. The Northern Sweden MONICA Center is located furthest to the north of all participating centers. In this report, baseline data on cardiovascular risk factors are presented. In the first population screening, 1,625 of 2,000 (81%) invited individuals participated. Diastolic blood pressure greater than or equal to 90 mmHg was recorded in 19% and 9% were on drug treatment for hypertension. Median cholesterol level was 6.10 mmol/l and the frequency of hypercholesterolemia was high. A body mass index of greater than or equal to 30, indicating severe obesity, was observed in 9%, a lower proportion than in most other European populations. Among men, the total proportion of tobacco consumers was 49%, including 22% snuffers. Of the women, 31% were tobacco consumers, very few being snuffers. Women had, in general, a more favorable cardiovascular risk factor profile up to the age of 45. Thereafter, the two genders were similar. By international comparisons, the population in northern Sweden is characterized by high serum cholesterol levels, intermediate blood pressure levels, a relatively low prevalence of severe obesity and a high consumption of smokeless tobacco.

Potassium-sparing diuretics

The hemodynamic and the endocrine disturbances in congestive heart failure (CHF) impose major changes in electrolyte balance with a retention of sodium and concomitant losses of potassium and magnesium from the body. These changes are of great importance for the development of cardiac dysrhythmias, a diminished glucose tolerance and for the well-being of the patient. The use of conventional diuretics imposes further burdens on the already deranged electrolyte balance. On long-term therapy with conventional diuretics in CHF we observed that approximately 50% of the 297 patients studied had potassium and magnesium deficiencies and an increased sodium content as judged by skeletal muscle biopsies. The magnesium deficiency is especially dangerous since it prevents the cells from keeping their high intracellular potassium concentration unchanged. Potassium substitution is without effect in a magnesium deficiency since magnesium is necessary for the transportation of potassium over the cell membrane against the concentration gradient. In case of magnesium depletion, potassium substitution may even have negative effects on the body potassium content. The reason for this is probably the increase of p-potassium concentration induced by the substitution, leading to an increase of aldosterone secretion. An increase of p-potassium levels by 0.2-0.4 mmol/l may thus result in a 50-100% rise in p-aldosterone concentration. These changes promote further urinary losses of potassium and magnesium. Several studies have demonstrated the positive effects of the potassium-sparing diuretics amiloride, spironolactone and triamterene on p-potassium concentration, but also on the body potassium content.(ABSTRACT TRUNCATED AT 250 WORDS)

Magnesium deficiency in congestive heart failure

In congestive heart failure several compensatory mechanisms are operating, and may cause severe disturbances of both the internal and external electrolyte balance. The medical treatment prescribed in congestive heart failure also leads to changes in the handling of electrolytes. These combined effects may prove critical to the patient, especially with regard to the emergence of cardiac arrhythmias.

Problems with potassium and magnesium in diuretic-treated patients

Treatment with thiazides and loop diuretics increase the urinary excretion of potassium and magnesium and the body content of these ions are reduced after long-term treatment. The diuretic-induced magnesium deficiency influences the potassium metabolism. Magnesium is a necessary activator of Na-K-ATPase, which supplies the Na-K pump with energy. Lack of magnesium will therefore impair the pumping of sodium out of the cell and of potassium into the cell. The change of the relationship between extra and intracellular potassium may induce cardiac arrhythmias. Certain groups of patients, such as patients on digitalis therapy, patients with secondary hyperaldosteronism, elderly patients with insufficient dietary habits, and heavy drinkers, run an additional risk of developing potassium/magnesium disturbances. In young patients with uncomplicated essential hypertension, the risk is probably very small.

Selenium and other trace elements in lung tissue in smelter workers relationship to the occurrence of lung cancer

In summary lower selenium concentrations were found in the lung cancer group compared to other smelter workers and controls. The two lowest selenium values in the total material were found in two of the lung cancer workers. This is in agreement with earlier reports of lower blood selenium levels in cancer patients (Willett et al 1983, Salonen et al 1984). An increased cancer incidence has also been found in geographical areas with low selenium contents in forage crops (Shamberger et al 1976). Numerous animal experiments have demonstrated an anticarcinogenic effect of selenium. Our conclusion is that selenium might have a protective effect in occupational exposure against at least certain carcinogens causing lung cancer. Looking at the dominant worksites the workers have obviously been exposed to different concentrations of selenium over the years. As selenium has not been particularly under observation, few dust analyses are available, and so the dust load in exposed workers cannot be directly calculated. The excretion rates show individual differences. In three of the seven lung cancer cases we noted that, despite a considerable and continuous exposure to selenium in the course of their work, they had low selenium concentrations in their lung tissue at the time of death. Two other workers in the lung cancer group had also been working at worksites with considerable exposure to selenium. Raised cadmium levels were noted in the lung cancer group.(ABSTRACT TRUNCATED AT 250 WORDS)

[Life after stroke--a new national study. Renewed follow-up of stroke patients shows increased dependency on the support from the next-of-kin]

The National Board of Health and Welfare together with Riks-Stroke (the Swedish National Registry for Quality Assessment of Acute Stroke Care) initiated a follow-up 2 years after a stroke event in 10,303 individuals, registrated in Riks-Stroke during the first 6 months of 2001. The aim was to evaluate the health status of the patients and the burden and needs of the spouses. 6,695 patients (65 percent) were alive. 4,729 patients (71 percent) answered the questionnaire. 2,367 spouses answered a separate questionnaire. This study was compared with an almost identical study performed four years earlier. The results showed that more patients lived at home and were satisfied with help and support. Rehabilitation was still deficient for 30 percent, and more patients were highly dependent on support from next-of-kin. Thirty percent could stay alone less than half a day. These results will be used for improving rehabilitation for the stroke patients and support for their spouses.

[Stroke--and then? Considerable need of assistance two year after stroke according to a large nation-wide study]

The National Board of Health and Welfare together with Riks-Stroke (the Swedish National Registry for Quality Assessment of Acute Stroke Care) were commissioned by the government to study the circumstances of 4,023 stroke patients, two years after the event. Both physical and psychological impairments together with psychosocial consequences were common. Approximately one fifth of the patients did not receive enough help and support, and the most common reason for this was the high cost. Instead many were dependent upon next-of-kin. This indicates that the long-term care of stroke patients needs to be improved.

Differences in long-term outcome between patients treated in stroke units and in general wards: a 2-year follow-up of stroke patients in sweden

BACKGROUND AND PURPOSE

The long-term beneficial effects of stroke unit care have been proved in several randomized trials. However, there is a question of large-scale applicability in routine clinical practice of interventions used by dedicated investigators in small randomized trials. The objective of this study was to compare, 21/2 years after stroke, patients who had been treated in stroke units and those treated in general wards in routine clinical practice.

METHODS

This is a prospective cohort study based on 8194 patients who were included, during the first 6 months in 1997, in Riks-Stroke, the Swedish National Register for quality assessment of acute stroke. Two years after the event, 5189 patients were still alive and 5104 were followed up with a postal questionnaire to which 4038 responded.

RESULTS

Among the group of patients who were independent in activities of daily living (ADL) functions before the stroke, patients who were treated in stroke units were less often dependent in ADL functions, after adjustment for case mix (OR, 0.79; CI, 0.66 to 0.94). If they also lived at home before the stroke, then they had a lower case-fatality rate 2 years after the stroke (OR, 0.81; CI, 0.72 to 0.92).

CONCLUSIONS

Long-term beneficial effects of treatment in stroke units were shown for patients who were independent in ADL functions before the stroke. No benefits were shown for patients who were dependent on help for primary ADL before the stroke. Further studies on this group of patients with more detailed outcome measures are needed.

Comparison of antihypertensive treatments in preventing cardiovascular events in elderly diabetic patients: results from the Swedish Trial in Old Patients with Hypertension-2. STOP Hypertension-2 Study Group

BACKGROUND

The benefits of treating hypertension in elderly diabetic patients, in terms of achieving reductions in cardiovascular morbidity and mortality, have been documented in several recent prospective trials. There has, however, been some controversy regarding the effect of different antihypertensive drugs on the frequency of myocardial infarction in this group of patients.

DESIGN

STOP Hypertension-2 was a prospective, randomized, open trial with blinded endpoint evaluation.

METHODS

We studied 6614 elderly patients aged 70-84 years; 719 of them had diabetes mellitus at the start of the study (mean age 75.8 years). Patients were randomly assigned to one of three treatment strategies: conventional antihypertensive drugs (diuretics or beta-blockers), calcium antagonists, or angiotensin converting enzyme (ACE) inhibitors.

RESULTS

Reduction in blood pressure was similar in the three treatment groups of diabetics. The prevention of cardiovascular mortality was also similar; the frequency of this primary endpoint did not differ significantly between the three groups. There were, however, significantly fewer (P = 0.025) myocardial infarctions during ACE inhibitor treatment (n = 17) than during calcium antagonist treatment (n = 32; relative risk 0.51, 95% confidence interval 0.28-0.92); but a (non-significant) tendency to more strokes during ACE inhibitor treatment (n = 34 compared with n = 29; relative risk 1.16, 95% confidence interval 0.71-1.91).

CONCLUSION

Treatment of hypertensive diabetic patients with conventional antihypertensive drugs (diuretics, beta-blockers, or both) seemed to be as effective as treatment with newer drugs such as calcium antagonists or ACE inhibitors.

Randomised trial of old and new antihypertensive drugs in elderly patients: cardiovascular mortality and morbidity the Swedish Trial in Old Patients with Hypertension-2 study

BACKGROUND

The efficacy of new antihypertensive drugs has been questioned. We compared the effects of conventional and newer antihypertensive drugs on cardiovascular mortality and morbidity in elderly patients.

METHODS

We did a prospective, randomised trial in 6614 patients aged 70-84 years with hypertension (blood pressure > or = 180 mm Hg systolic, > or = 105 mm Hg diastolic, or both). Patients were randomly assigned conventional antihypertensive drugs (atenolol 50 mg, metoprolol 100 mg, pindolol 5 mg, or hydrochlorothiazide 25 mg plus amiloride 2.5 mg daily) or newer drugs (enalapril 10 mg or lisinopril 10 mg, or felodipine 2.5 mg or isradipine 2-5 mg daily). We assessed fatal stroke, fatal myocardial infarction, and other fatal cardiovascular disease. Analysis was by intention to treat.

FINDINGS

Blood pressure was decreased similarly in all treatment groups. The primary combined endpoint of fatal stroke, fatal myocardial infarction, and other fatal cardiovascular disease occurred in 221 of 2213 patients in the conventional drugs group (19.8 events per 1000 patient-years) and in 438 of 4401 in the newer drugs group (19.8 per 1000; relative risk 0.99 [95% CI 0.84-1.16], p=0.89). The combined endpoint of fatal and non-fatal stroke, fatal and non-fatal myocardial infarction, and other cardiovascular mortality occurred in 460 patients taking conventional drugs and in 887 taking newer drugs (0.96 [0.86-1.08], p=0.49).

INTERPRETATION

Old and new antihypertensive drugs were similar in prevention of cardiovascular mortality or major events. Decrease in blood pressure was of major importance for the prevention of cardiovascular events.

[Stroke unit care saves lives. The Swedish national quality assessment registry of stroke care is the first of its kind in the world]

Meta-analyses of randomised trials of acute stroke treated in specialised stroke units have yielded convincing evidence of benefits in terms of reduced mortality rates, as compared with treatment in a general ward. However, no studies had been performed to ascertain whether the promising results could be reproduced in routine clinical practice. Accordingly, a comparison of routine care of acute stroke patients in stroke units (SUs) with that in general wards (GWs) was made on the basis of data for the 14,300 cases of acute stroke from 87 units in 80 Swedish hospitals registered in 1996 at the Swedish national stroke registry, the first of its kind in the world. Among patients capable of independent daily life and fully conscious at admission, the mortality rate was lower in the SU than in the GW subgroup, both at discharge from hospital and three months after the stroke event; and three months after stroke, a greater proportion of SU patients had been discharged to their homes, and a smaller proportion were in long-term care. However, no such subgroup differences were found among patients with impaired consciousness at admission. Thus, the promising results of the randomised trials of SU treatment would appear to be reproducible in routine clinical practice, though the beneficial effect is smaller in magnitude.

Stroke units in their natural habitat: can results of randomized trials be reproduced in routine clinical practice? Riks-Stroke Collaboration

BACKGROUND AND PURPOSE

Meta-analyses of randomized controlled trials of acute stroke care have shown care in stroke units (SUs) to be superior to that in conventional general medical, neurological, or geriatric wards, with reductions in early case fatality, functional outcome, and the need for long-term institutionalization. This study examined whether these results can be reproduced in clinical practice.

METHODS

A multicenter observational study of procedures and outcomes in acute stroke patients admitted to designated SUs or general medical or neurological wards (GWs), the study included patients of all ages with acute stroke excluding those with subarachnoid hemorrhage, who were entered into the Riks-Stroke (Swedish national quality assessment) database during 1996 (14 308 patients in 80 hospitals).

RESULTS

Patients admitted to SUs who had lived independently and who were fully conscious on admission to the hospital had a lower case fatality than those cared for in GWs (relative risk [RR] for death, 0.87; 95% confidence interval [CI], 0.79 to 0.96) and at 3 months (RR, 0.91; 95% CI, 0.85 to 0.98). A greater proportion of patients cared for in an SU could be discharged home (RR, 1.06; 95% CI, 1.03 to 1.10), and fewer were in long-term institutional care 3 months after the stroke (RR, 0.94; 95% CI, 0.89 to 0.99). No difference was seen in outcome in patients cared for in SUs or GWs if they had impaired consciousness on admission.

CONCLUSIONS

The improvement in outcomes after stroke care in SUs compared with care in GWs can be reproduced in the routine clinical setting, but the magnitude of the benefit appears smaller than that reported from meta-analyses.

Effect of angiotensin-converting-enzyme inhibition compared with conventional therapy on cardiovascular morbidity and mortality in hypertension: the Captopril Prevention Project (CAPPP) randomised trial

BACKGROUND

Angiotensin-converting-enzyme (ACE) inhibitors have been used for more than a decade to treat high blood pressure, despite the lack of data from randomised intervention trials to show that such treatment affects cardiovascular morbidity and mortality. The Captopril Prevention Project (CAPPP) is a randomised intervention trial to compare the effects of ACE inhibition and conventional therapy on cardiovascular morbidity and mortality in patients with hypertension.

METHODS

CAPPP was a prospective, randomised, open trial with blinded endpoint evaluation. 10,985 patients were enrolled at 536 health centres in Sweden and Finland. Patients aged 25-66 years with a measured diastolic blood pressure of 100 mm Hg or more on two occasions were randomly assigned captopril or conventional antihypertensive treatment (diuretics, beta-blockers). Analysis was by intention-to-treat. The primary endpoint was a composite of fatal and non-fatal myocardial infarction, stroke, and other cardiovascular deaths.

FINDINGS

Of 5492 patients assigned captopril and 5493 assigned conventional therapy, 14 and 13, respectively, were lost to follow-up. Primary endpoint events occurred in 363 patients in the captopril group (11.1 per 1000 patient-years) and 335 in the conventional-treatment group (10.2 per 1000 patient-years; relative risk 1.05 [95% CI 0.90-1.22], p=0-52). Cardiovascular mortality was lower with captopril than with conventional treatment (76 vs 95 events; relative risk 0.77 [0.57-1-04], p=0.092), the rate of fatal and non-fatal myocardial infarction was similar (162 vs 161), but fatal and non-fatal stroke was more common with captopril (189 vs 148; 1.25 [1-01-1-55]. p=0.044).

INTERPRETATION

Captopril and conventional treatment did not differ in efficacy in preventing cardiovascular morbidity and mortality. The difference in stroke risk is probably due to the lower levels of blood pressure obtained initially in previously treated patients randomised to conventional therapy.

The Captopril Prevention Project (CAPPP) in hypertension--baseline data and current status

The Captopril Prevention Project (CAPPP) is an ongoing intervention study conducted in 11,019 hypertensive patients in Sweden and Finland. Patients have been randomized to receive either conventional antihypertensive therapy (diuretics and/or beta-blockers) or captopril-based treatment. A prospective, randomized, open, blinded-endpoint evaluation (PROBE) study design is used to compare these two therapeutic regimens as regards cardiovascular morbidity and mortality. The rationale for the CAPPP Study are the many observations of beneficial effects of ACE inhibition, as compared to diuretics and beta-blockers, on intermediary endpoints such as insulin sensitivity, serum lipoproteins, left ventricular hypertrophy and renal function. Captopril has also been shown to be markedly effective in the treatment of left ventricular dysfunction as well as congestive heart failure. The hypothesis is that these differences might result in improved risk reduction when ACE inhibitors are used in the treatment of hypertension. The present paper describes the baseline data and the changes in blood pressure during the first year in the total cohort. During the first year the average blood pressure was reduced by 11/8 mm Hg. A number of substudies have been conducted in the CAPPP Study. In one of these insulin sensitivity was compared in a subgroup of the patients using the euglycemic insulin clamp technique. In another substudy the ACE gene was sequenced and some new polymorphisms were discovered. Several other substudies are in progress or in the planning phase. The main results of the CAPPP Study should be available by mid-1998. Some of the intended anayses of the final results as well as other planned substudies are briefly described here.

Magnesium therapy, fibrinolytic parameters and von Willebrand factor in acute myocardial infarction

Sixty-one patients with non-thrombolytic treated acute myocardial infarction were randomised to open magnesium infusion or control. tPA activity, tPA mass, PAI-1 mass and von Willebrand factor (vWF) were measured in blood samples drawn at entrance and after on average 10 h and 18 h following inclusion in the trial. No differences for the hemostatic variables assay type were detected between the two groups. Fluctuations in the fibrinolytic parameters were maintained in the magnesium group, but blunted in the control group regarding PAI-mass and tPA-activity. This study gives no evidence that magnesium infusion in acute myocardial infarction influences fibrinolytic parameters or vWF.

The Swedish Trial in old patients with hypertension-2 (STOP-hypertension-2): a progress report

OBJECTIVE

The Swedish Trial in Old Patients with Hypertension-2 (STOP-Hypertension-2) was designed by a project group of the Swedish Hypertension Society to test whether the "newer" treatment alternatives (ACE inhibitors and calcium antagonists) are as good as, better or less good than, the "older" ones (beta-blockers and diuretics) in terms of preventing cardiovascular morbidity and mortality in elderly hypertensives. The aim of the present paper is to report on the progress of the study.

DESIGN

Prospective, open trial with blinded end-point committee and centralized randomization (PROBE design). STOP-Hypertension-2 may be regarded as a scientific follow-up of the previously published Swedish Trial in Old Patients with Hypertension (STOP-Hypertensioon-1) (6) using the same study organization.

SUBJECTS

By the end of 1994 when recruitment was stopped, 6628 hypertensive men (34%) and women (66%) aged 70-84 (mean age 76) had been included at 312 Swedish health centres (out of approximately 850). In the whole cohort 11% are diabetics and 9% smokers. The mean total cholesterol value is 6.5 mmol/L.

RESULTS

In the whole study cohort, blood pressure was lowered from 194/98 mmHg to 167/85 mmHg after one year. At the end of 1995, 319 fatal events (all-cause mortality) had been reported, corresponding to a mortality rate of 21.3 per 1000 person-years.

CONCLUSION

In STOP-Hypertension-2, 6628 elderly hypertensive have been randomized to three different treatment regimes: beta-blocker+diuretics (the active treatment arm in STOP-Hypertension-1), ACE inhibitors, or calcium antagonists. Their average lowering of blood pressure was 27/13 mmHg and end-points have occurred at the expected rate. Thus, it should be possible to terminate STOP-Hypertension-2 within two to three years.

Skeletal muscle magnesium and potassium in asthmatics treated with oral beta 2-agonists

Dietary magnesium has been shown to be important for lung function and bronchial reactivity. Interest in electrolytes in asthma has so far mainly been focused upon serum potassium, especially linked to beta 2-agonist treatment. It is known that serum levels of magnesium and potassium may not correctly reflect the intracellular status. We therefore investigated whether asthmatics treated with oral beta 2-agonists had low magnesium or potassium in skeletal muscle and serum, and whether withdrawal of the oral beta 2-agonists would improve the electrolyte levels. Magnesium and potassium levels in skeletal muscle biopsies, serum and urine were analysed in 20 asthmatics before and 2 months after withdrawal of long-term oral beta 2-agonists, and for comparison in 10 healthy subjects. Skeletal muscle magnesium in the asthmatics was lower both before (3.62 +/- 0.69 mmol.100 g-1 (mean +/- SD)) and after (3.43 +/- 0.60 mmol.100 g-1) withdrawal of oral beta 2-agonists compared with the controls (4.43 +/- 0.74 mmol.100 g-1). Skeletal muscle potassium and serum magnesium did not differ between the groups. Serum potassium was significantly lower both before (4.0 +/- 0.2 mmol.L-1) and after (3.9 +/- 0.2 mmol.L-1) the withdrawal of oral beta 2-agonists compared with the control group (4.2 +/- 0.2 mmol.L-1). The asthmatics had lower skeletal muscle magnesium and lower serum potassium than the healthy controls, both with and without oral beta 2-agonists. Whether the findings are related to asthma pathophysiology or treatment is currently being investigated.

Effects of intravenous magnesium sulphate in suspected acute myocardial infarction on acute arrhythmias and long-term outcome

A total of 252 patients with suspected acute myocardial infarction were included in a double blind study and randomised to 50 mmol magnesium sulfate infusion under 20 h or corresponding placebo. Acute myocardial infarction was verified in 117 patients and 59% of these had concomitant treatment with thrombolysis. One-hundred ninety-four patients had Holter registrations during the first day in the coronary care unit. Intention-to-treat analysis showed an increase in long RR-intervals (> 3 s) in the magnesium treated group (P = 0.006) and a tendency toward a reduction in episodes of ventricular premature complexes in triplets (P = 0.09). During hospital stay and a mean of 22 months follow-up, 23 fatal events occurred in the magnesium allocated group and 31 fatal events among the placebo allocated group (P = 0.1). Mortality rate from cardiac disease was reduced by 54% (95% C.I. 30-99%, P < 0.05). Subgroup analysis on acute myocardial infarction patients showed a 48% mortality risk reduction in the magnesium treated acute myocardial infarction group compared to the placebo treated acute myocardial infarction group (95% C.I. 23-104%, P = 0.06). There was no significant interaction between the effects of magnesium and thrombolytic treatment on total mortality or cardiac events. This study supports the results of other small double blind placebo controlled studies regarding effects of magnesium therapy on mortality in acute myocardial infarction, but are in discordance to the conclusion from the ISIS-4 study. The reasons for these discrepancies cannot be elucidated by our data.

Nutritional magnesium supplementation does not change blood pressure nor serum or muscle potassium and magnesium in untreated hypertension. A double-blind crossover study

The aim of this study was to evaluate if a nutritional dose of magnesium given orally changes the blood pressure in untreated hypertensive patients and if orally-given magnesium had any influence on serum and muscle magnesium and potassium. A randomized, double-blind crossover study design was followed with magnesium 15 mmol/day or placebo treatment for two months. Thirty-nine patients aged 20-59 years, were treated. Samples for magnesium and potassium in blood, muscle and urine were taken at entry time, after two months (crossover time) and after four months (end of study). Systolic and diastolic supine and standing blood pressures were measured at the same times. No significant change in blood pressure, serum or muscle concentrations of electrolytes were observed on magnesium treatment. Urine magnesium rose significantly on magnesium, and it decreased significantly on placebo. Therefore results suggest that 15 mmol magnesium/day, given to untreated mild-to-moderate hypertensives does not alter blood pressure nor the concentrations of magnesium and potassium in serum and muscle, in patients with normal magnesium turnover.