People with diabetes have a substantial lower life expectancty

Background

People with diabetes live shorter lives on average than people without diabetes. This is not only because they have diabetes, but also more often other chronic diseases. This causes a greater risk of death. It makes a difference what kind of diabetes someone has. In type 1 diabetes, the natural immune system does not work properly. In type 2, an unhealthy lifestyle plays a role. An unhealthy lifestyle increases the chance that someone will get type 2 diabetes and the chance that that person will die of another disease, such as cardiovascular disease.

Methods

RIVM has linked general practitioners’ data from 2012-2019 to the vital statistics of the Dutch National Statistical Office. The population of people registered with and without diabetes were coupled with the mortality data. Making use of life tables, associated life expectancies were calculated. For people under the age of 45, no robust analysis could be made.

Results

People aged 45 with type 1 diabetes live on average 13 years shorter than people without diabetes. For a 45-year-old with type 2 diabetes, that is on average 4 years shorter. The chance of dying is about 5 times greater for people aged 45 to 60 with type 1 diabetes than for people without diabetes of this age. This difference becomes smaller as they get older, because people without diabetes also get one or more diseases more often. In type 2 diabetes, the mortality rate for people aged 45 to 60 years is about 2 times greater than for people without diabetes. Again, the difference decreases as they age.

Conclusions

A substantial lower life expectancy of 13 years for type 1 and 4 years for type 2 diabetes has different societal and policy consequences. Since type diabetes 1 is unavoidable, more attention should be given to living with this condition, while for type 2 prevention of for example overweight should get attention.

Key messages

• People with for type 1 and type 2 diabetes have 13 and 4 years lower life expectancy.

• More attention should be given to prevention and to living with diabetes.

Social functioning and subclinical psychosis in adolescence: a longitudinal general adolescent population study

OBJECTIVES

To investigate the longitudinal relationship between subclinical psychotic symptoms and social functioning in a representative general population sample of adolescents.

METHOD

Data were derived from a routine general health screening of 1909 adolescents in a circumscribed region. Baseline measurement was in the second grade of secondary school (T0), and follow-up occurred approximately 2 years later (T1). Social functioning and subclinical psychotic symptoms of hallucinations and delusions were assessed at both time points.

RESULTS

Baseline (T0) social problems preceded follow-up (T1) subclinical delusions, but not T1 subclinical hallucinations. Similarly, T0 delusions preceded social problems at T1, but T0 hallucinations did not.

CONCLUSION

This longitudinal general population study demonstrated a bidirectional association between social problems and delusions, but found no link between social problems and hallucinations. This may reflect a downward negative spiral where delusional thoughts and social problems reinforce each other.

Activation of the Fibrinolytic System in Patients with Coronary Artery Disease and Hyperfibrinogenemia

Elevated fibrinogen levels as well as an impaired activity of the fibrinolytic system are regarded as important cardiovascular risk factors. To elucidate a potential interrelation between fibrinogen as an indicator of a hypercoagulable state and the endogenous fibrinolytic function hemostatic and rheological as well as lipid parameters were determined in 224 consecutive patients, who underwent elective coronary angiography. In the selected study population of 81 men and 19 women with fibrinogen concentrations either ≥3.5 g/1 (n = 70) or ≤2.5 g/1 (n = 30) hyperfibrinogenemia was found to be significantly associated with increased concentrations of plasmin-α2-antiplasmin complex [PAP [median (25.-75. percentile)], 534 (361-680) μg/l vs. 289 (243-440) μg/1; p <0.001] and tissue plasminogen activator (t-PA) antigen [9 (6-11) μg/1 vs. 8 (5-9) |xg/l; p <0.05] while this association was lost in the subgroup of patients with angiographically normal coronary arteries (n = 26). In addition to these findings fibrinogen was significantly correlated with PAP (r = 0.40, p <0.001; n = 224) and t-PA antigen (r = 0.2, p <0.01; n = 224) after adjustment for age, diabetes mellitus, lipid parameters and leucocyte counts. It can be argued that elevated fibrinogen levels in patients with coronary artery disease are concomitant with an activation of the fibrinolytic system.

Depressive symptoms are associated with (sub)clinical psychotic symptoms in patients with non-affective psychotic disorder, siblings and healthy controls

BACKGROUND

Depression is a clinically relevant dimension, associated with both positive and negative symptoms, in patients with schizophrenia. However, in siblings it is unknown whether depression is associated with subclinical positive and negative symptoms. Method Depressive symptoms and their association with positive and negative symptoms were examined in 813 healthy siblings of patients with a non-affective psychotic disorder, 822 patients and 527 healthy controls. Depressive episodes meeting DSM-IV-TR criteria (lifetime) and depressed mood (lifetime) were assessed with the Comprehensive Assessment of Symptoms and History (CASH) in all three groups. In the patient group, the severity of positive and negative psychosis symptoms was assessed with the CASH. In the siblings and healthy controls, the severity of subclinical psychosis symptoms was assessed with the Community Assessment of Psychic Experiences (CAPE).

RESULTS

Patients reported more lifetime depressed mood and more depressive episodes than both siblings and controls. Siblings had a higher chance of meeting lifetime depressive episodes than the controls; no significant differences in depressed mood were found between siblings and controls. In all three groups the number and duration of depressive symptoms were associated with (sub)clinical negative symptoms. In the patients and siblings the number of depressive symptoms was furthermore associated with (sub)clinical positive symptoms. Finally, lifetime depressed mood showed familial clustering but this clustering was absent for lifetime depressive episodes.

CONCLUSIONS

These findings suggest that a co-occurring genetic vulnerability for both depressive and psychotic symptomatology exists on a clinical and a subclinical level.

Relevance of hemostasis on restenosis in clinically stable patients undergoing elective PTCA

BACKGROUND

Secondary coronary thrombus formation is considered to be co-factor in the pathogenesis of restenosis after percutaneous transluminal coronary angioplasty (PTCA). Therefore systemic factors indicating a hypercoagulable disease state may be relevant for the process of coronary renarrowing. Even though experimental data suggest that in particular thrombin may be of major relevance for restenosis induced by mechanical injury, only little clinical data has been presented so far.

METHODS AND RESULTS

In 60 consecutive patients, who had been clinical stable for at least 2 months, and who underwent elective and primarily successful PTCA, follow-up films were evaluated by means of quantitative coronary angiography in respect to a categorical and a continuous definition of restenosis, luminal narrowing >50% and late luminal loss respectively. Of the chosen laboratory variables prothrombin fragment 1+2 (1.3+/-0.5 vs. 0.9+/-0.4 mmol/l, p<0.001) red blood cell aggregation at low shear stress (13.5+/-2.9 vs. 11.6+/-2.8 units, p<0.05), and plasminogen-activator inhibitor (3.7+/-1.8 vs. 5.3+/-3.2 U/ml p<0.05) differentiated between patients with (n=18) and without restenosis (n=42). Late luminal loss correlated positively with prothrombin fragment 1+2 (r=0.41, p<0.001), plasminogen-activator inhibitor (r= -0.28, p<0.05) and plasmin-alpha2-antiplasmin complex (r=0.39, p<0.01).

CONCLUSIONS

A hypercoagulable disease state and in particular thrombin generation characterize a high-risk group prone for restenosis in clinically stable coronary artery disease.

Changes of hemostasis, endogenous fibrinolysis, platelet activation and endothelins after percutaneous transluminal coronary angioplasty in patients with stable angina

OBJECTIVES

This study investigated parameters of endogenous fibrinolysis, activation of coagulation and platelets, and endothelin levels before and after elective percutaneous transluminal coronary angioplasty (PTCA) in patients with stable coronary artery disease (CAD).

BACKGROUND

Abrupt vessel closure is a serious short-term complication after PTCA and is often unforeseeable. Detailed insight into the effect of PTCA on hemostasis, platelets and the release of vasoconstrictive substances, which are among the mainly discussed mechanisms of abrupt vessel closure, is needed to enhance the safety of coronary intervention.

METHODS

Plasma levels of markers of platelet activity, coagulation, endogenous fibrinolysis and endothelins were determined in 20 patients with stable CAD undergoing elective PTCA. The blood specimens were drawn before, immediately after, 1 h after intervention and on the next morning.

RESULTS

All patients showed an initially uncomplicated PTCA. Regarding the efficacy of anticoagulation after receiving 15.000 IU heparin during PTCA, two groups were compared. In eight patients with ineffective anticoagulation production of thrombin and platelet activation directly after and 1 h after PTCA was significantly higher compared with 12 patients with effective anticoagulation. Despite the strong activation of coagulation, only a low fibrinolytic response could be observed. Endothelins rose significantly after PTCA in both groups but stayed longer on higher levels in patients with distinct thrombin generation. Three of the eight patients without sufficient heparin treatment suffered abrupt vessel closure.

CONCLUSIONS

Initially uncomplicated dilation of coronary arteries leads to systemically measurable activation of coagulation and platelets in patients with ineffective doses of heparin and release of endothelins in all patients. Therefore, individual adjustment of anticoagulation and platelet inhibition in combination with effective antivasospastic substances are needed in every patient before, during and after initially uncomplicated PTCA to prevent this serious complication.

Präanalytik in der Gerinnungsdiagnostik – Welchen Einfluß haben Lagerungsdauer und Lagerungstemperatur auf Meßgrößen des Gerinnungssystems?

Bis heute fehlen in der Hämostaseologie größere umfassende Studien über die Stabilität von Meßgrößen des Gerinnungssystems im Plasma. Daher haben wir den Einfluß von Lagerungsdauer und -temperatur auf Thromboplastinzeit, aPTT (aktivierte partielle Thromboplastinzeit), Thrombinzeit, Fibrinogen, Faktor V und VIII, Antithrombin, Protein C und Protein S im Plasma von 20 gesunden Probanden und 20 Patienten, die Heparin in therapeutischen Dosen erhielten, untersucht. Die Stabilität im Plasma war definiert als der Zeitraum, in dem im Vergleich zum Ausgangswert eine Änderung von weniger als 10% gemessen wurde. Während der Lagerung bei 6° C lag die Stabilität in der Gruppe der gesunden Probanden für die aPTT bei 8 h, für die Thromboplastinzeit bei 24 h, für Faktor V bei 48 h und 7 Tage für Thrombinzeit, Fibrinogen, Antithrombin, Protein C. Faktor VIII und Protein S zeigten eine 19- bzw. 12prozentige Verminderung der Aktivität nach 8 h.

Bei den Probanden, die nicht mit Heparin behandelt wurden, war die aPTT 8 h lang, die Thromboplastinzeit 48 h und Thrombinzeit, Fibrinogen und Antithrombin 7 Tage lang während der Probenlagerung bei Raumtemperatur stabil. Faktor VIII zeigte eine Abnahme von 18% nach 8 h. Für Patienten, die eine Heparintherapie erhielten, lag die Stabilität unter 6° C bei 8 h für die Thrombinzeit, 24 h für die Thromboplastinzeit und aPTT sowie 7 Tage für Fibrinogen und Antithrombin. Faktor V und VIII zeigten eine Abnahme von 13 bzw. 20% nach 8 h. Sobald das Plasma von diesen Patienten bei Raumtemperatur gelagert wurde, war Faktor V über 8 h stabil, die Thromboplastinzeit über 24 h und sowohl Fibrinogen als auch Antithrombin blieben über 7 Tage unverändert. Die aPTT zeigte einen Anstieg von 13%, die Thrombinzeit einen Abfall um 16% und Faktor VIII einen Abfall um 18% nach 8 h.

Influence of time and temperature on coagulation analytes in stored plasma

There is no comprehensive study on the stability of coagulation analytes in plasma. We therefore determined the influence of storage time and temperature on prothrombin time, activated partial thromboplastin time, thrombin time, fibrinogen, factors V and VIII, antithrombin III, protein C and S in plasma from 20 healthy subjects and 20 patients receiving heparin therapy. The stability in plasma, defined as the period during which there was a change of less than 10% from the initial value, was 8 hours for activated partial thromboplastin time, 24 hours for prothrombin time, 48 hours for factor V and 7 days for thrombin time, fibrinogen, protein C and antithrombin III in healthy subjects at 6 degrees C. Factor VIII and protein S showed 19 and 12 % reduction in activity, respectively, after 8 hours. In volunteers not treated with heparin therapy, activated partial thromboplastin time was stable for 8 hours; prothrombin time for 48 hours; and thrombin time, fibrinogen and antithrombin III for 7 days with sample storage at room temperature. Factor VIII showed a decrease of 18 % after 8 hours. For patients receiving heparin therapy, the stability of the analytes in plasma stored at 6 degrees C was 8 hours for thrombin time, 24 hours for prothrombin time and activated partial thromboplastin time and 7 days for fibrinogen and antithrombin III. Factors V and VIII showed a decrease of 13 % and 20 % respectively after 8 hours. When the plasma of these patients was stored at room temperature, factor V was stable for 8 hours, and prothrombin time for 24 hours, whereas fibrinogen and antithrombin III remained unchanged for 7 days. Activated partial thromboplastin time showed an increase of 13 %, thrombin time a fall of 16 %, and factor VIII a decrease of 18 % after 8 hours.

Plasma levels of D-dimer and circulating endothelial adhesion molecules in veno-occlusive disease of the liver following allogeneic bone marrow transplantation

Veno-occlusive disease (VOD) of the liver is a frequent and life-threatening complication of BMT. Recently, successful treatment by t-PA has been reported but has been compromised by fatal bleeding events. Therefore, t-PA application should be restricted to patients with severe VOD. However, moderate and severe forms of VOD are difficult to distinguish in early stages. We analyzed plasma levels of cross-linked fibrin degradation products (D-dimer) and soluble endothelial adhesion molecules such as sE-selectin, sVCAM-1 and sICAM-1 in 10 consecutive patients undergoing allogeneic BMT to evaluate their use in identifying severe forms of VOD. During the observation period, 4 episodes of VOD occurred, 2 of which were fatal due to early onset of multiorgan failure. Concentrations of D-dimer generally increased after transplantation. However, there was an additional significant increase in D-dimer levels during severe VOD. Thus, D-dimer levels above 1000 microg/l were only found in 2 cases with severe VOD and fatal outcome. When compared with bilirubin concentrations substantial increases of D-dimers appeared earlier during the course of severe VOD. In contrast, VOD episodes were not accompanied by significant increases in sE-selectin, sVCAM-1 and sICAM-1 levels. It is concluded that measurement of D-dimer concentrations may aid accuracy to the early diagnosis of severe VOD.

Specific pattern of circulating endothelial adhesion molecules in HIV-associated Kaposi's sarcoma

BACKGROUND

Circulating endothelial adhesion molecules have been found to be increased in states of immune activation, but little is known about their significance in the assessment of endothelial neoplasms. One of the most common tumors supposed to be derived from endothelial origin is HIV-associated Kaposi's sarcoma (KS).

METHODS

Plasma concentrations of sCD54 (= intercellular adhesion molecule-1), sCD106 (= vascular cell adhesion molecule-1), and sCD62E (= E-selectin) were quantified by sandwich ELISA in 54 AIDS patients who were either free of active opportunistic disorders (n = 15, AIDS controls), or suffering from acute infections (n = 16), or exhibiting KS (n = 23), and in 18 age- and sex-matched healthy HIV-negative controls.

RESULTS

Both sCD54 and sCD106 plasma levels were consistently increased in all AIDS patients irrespective of concurrent opportunistic disorders (p < 0.005), while sCD62E levels were not altered in AIDS patients without KS (p > 0.05). In KS patients, sCD62E concentrations were decreased both compared to healthy (p = 0.0007) and to AIDS controls (p = 0.04), and stimulated sCD54 levels were less elevated than those of AIDS controls (p = 0.02). Plasma concentrations of all three adhesion molecules did not correlate to KS tumor stage.

CONCLUSION

There appears to be a specific pattern of circulating endothelial adhesion molecules in AIDS patients with associated KS. Although the present findings do not support a role for their determination as tumor markers, they might be involved in KS tumor pathogenesis.

Activation of the fibrinolytic system in patients with coronary artery disease and hyperfibrinogenemia

Elevated fibrinogen levels as well as an impaired activity of the fibrinolytic system are regarded as important cardiovascular risk factors. To elucidate a potential interrelation between fibrinogen as an indicator of a hypercoagulable state and the endogenous fibrinolytic function hemostatic and rheological as well as lipid parameters were determined in 224 consecutive patients, who underwent elective coronary angiography. In the selected study population of 81 men and 19 women with fibrinogen concentration either > or = 3.5 g/l (n = 70) or < or = 2.5 g/l (n = 30) hyperfibrinogenemia was found to be significantly associated with increased concentrations of plasmin-alpha 2-antiplasmin complex [PAP [median (25.-75. percentile)], 534 (361-680) micrograms/l vs. 289 (243-440) micrograms/l; p < 0.001] and tissue plasminogen activator (t-PA) antigen [9 (6-11) micrograms/l vs 8 (5-9) micrograms/l; p < 0.05] while this association was lost in the subgroup of patients with angiographically normal coronary arteries (n = 26). In addition to these findings fibrinogen was significantly correlated with PAP (r = 0.40, p < 0.001; n = 224) and t-PA antigen (r = 0.2, p < 0.01; n = 224) after adjustment for age, diabetes mellitus, lipid parameters and leucocyte counts. It can be argued that elevated fibrinogen levels in patients with coronary artery disease are concomitant with an activation of the fibrinolytic system.

[Endothelin and big endothelin in coronary heart disease and acute coronary syndromes]

Endothelin (ET), the most potent endogenous vasoconstrictor with mitogenic potency, is generated from its precursor big-endothelin (BET) in a proteolytic process and discussed as a pathogenetic factor in coronary artery disease and in the acute coronary syndromes. Several studies documented elevated plasma endothelin concentrations in acute myocardial infarction, but conflicting results were reported in patients with stable and unstable angina. Only few studies determined big endothelin, although it half-life and plasma concentrations are higher in comparison to endothelin. ET and BET levels (Radioimmunoassay, Biomedica GmbH, Vienna) were determined in patients with stable angina (SAP, n = 20), unstable angina (IAP, n = 12), acute myocardial infarction (AMI, n = 12) and healthy subjects (NP, n = 11). The concentrations of ET and BET (median (minimum-maximum) in fmol/ml) of the patients with stable angina (SAP: ET 0.7 (0.3-1.1); BET 1.7 (0.7-2.9)), unstable angina (IAP: ET 1.0(0.5-1.7); BET 2.5 (1.3-4.1)) and acute myocardial infarction (AMI: ET 1.2 (0.6-2.3); BET 3.6 (3.2-5.3)) showed a significant difference compared to controls (NP: ET 0.5 (0.4-0.7); BET 1.4 (1.1-1.7)) (SAP vs. NP: ET p < 0.01; BET p < 0.05; IAP and AMI vs. NP: ET and BET p < 0.001). Also, the concentrations of the peptides differed significantly dependent on the clinical severity of coronary artery disease (AMI vs. SAP: ET and BET p < 0.001; AMI vs. IAP: BET p < 0.05; IAP vs. SAP: ET p < 0.05; BET p < 0.01). Twelve of 15 patients with big endothelin concentrations over 3 fmol/ml suffered acute myocardial infarction. Seven of 12 patients with AMI showed elevated ET and BET concentrations before the increase of creatinecinase. There was no correlation between number of risk factors per patient, cholesterin and subfractions, severity of CAD classified in one-two-three-vessel disease or coronary score according to modified criteria of the American Heart Association (AHA). We conclude that in patients with coronary artery disease endothelin and big endothelin levels are elevated and related to the clinical and not to the morphological severity of coronary artery disease. Big endothelin is the more sensitive parameter in comparison to endothelin and indicates a severe course of myocardial ischemia in patients with unstable angina. The development of assays with the possibility of a quick determination of the peptides may be valuable for risk stratification of acute coronary events.

Automation in coagulation testing

Belatedly, automation is being introduced into hemostasis laboratories. Now, new analytic systems are also available for less specialized laboratories. New tests have been added as knowledge of the mechanisms of coagulation increases. This article will review the new technologies in coagulation testing and their diagnostic applications.

Storage of serum or whole blood samples? Effects of time and temperature on 22 serum analytes

Information on the stability of serum analytes during storage of serum or whole blood samples is often incomplete and sometimes contradictory. Using a widely available analyser (Hitachi 737/Boehringer), we therefore determined the effects of storage time and temperature on the measured concentrations of the following serum analytes: sodium, potassium, calcium, chloride, inorganic phosphate, magnesium, creatinine, urea, uric acid, bilirubin, cholesterol, HDL- and LDL-cholesterol, triacylglycerols, creatine kinase, aspartate aminotransferase, alanine aminotransferase, gamma-glutamyltransferase, alkaline phosphatase, alpha-amylase, lactate dehydrogenase and cholinesterase. When separated serum was stored at + 9 degrees C for seven days, the mean changes in inorganic phosphate and lactate dehydrogenase exceeded significantly (p < 0.05 or 0.001, respectively) the maximum allowable inaccuracy according to the Guidelines of the German Federal Medical Council; all other quantities were sufficiently stable. In serum at room temperature, inorganic phosphate, uric acid, HDL-cholesterol and triacylglycerols increased continuously, whereas bilirubin, LDL-cholesterol, creatine kinase and aspartate aminotransferase decreased more than the guidelines permit during the storage period (p < 0.05 for aspartate aminotransferase, p < 0.001 for the other analytes mentioned). In whole blood stored for 7 days at + 9 degrees C, only the following serum analytes satisfied the stability requirements of the guidelines: calcium, urea, cholesterol, HDL-cholesterol, LDL-cholesterol, triacylglycerols, creatine kinase, gamma-glutamyltransferase and cholinesterase. When stored at room temperature, only sodium, uric acid, bilirubin, cholesterol, triacylglycerols, aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, alpha-amylase and cholinesterase were still stable after 3 days. The data collected show that all quantities examined are sufficiently stable for four days in separated serum stored at + 9 degrees C.

Erworbene Faktor Vlll·C-Hemmkörper bei Nichthämophilen

Antibodies against factor VIII:C occur in about 5-15 % of hemophilia A patients and induce refractoriness to factor VIII:C infusions. These antibodies are mostly of IgG class. In very rare cases factor VIII:C inhibitors also develop in nonhemophilic patients. Although there are anecdotal reports that these antibodies may disappear spontaneously, in the majority of patients the clinical course is characterized by severe hemorrhages. During the last ten years we treated 9 nonhemophilic patients with acquired factor VIII:C inhibitors at our clinic. In most cases, a sudden bleeding tendency was observed shortly after an injury or surgery. Coagulation tests showed a prolonged aPTT and a decreased F VIIL:C level. Therapy with F VIII·C concentrates did not produce the expected increase. Measurement of F VIII:C inhibitor levels (Bethesda Units = BU) revealed values in the range between 2 and 108 BU. Immunosuppressive therapy in patients with > 5 BU using azathioprine or cyclo-phosphamide in combination with prednisone lead to complete disappearance of the inhibitor, normalization of the coagulation tests, and complete remission of the bleeding tendency in 7 patients within 6 weeks. During pregnancy only prednisone should be given. On the other hand in women with post-partum factor VIII inhibitors, steroid treatment appears to be not superior to no treatment, but immunosup-pression with cyclophosphamide or azathioprine seems to be more effective. In emergency situations, therapy with high doses of human F VIII:C concentrate is recommended. When bleeding does not cease, the additional use of activated pro-thrombin concentrates or porcine factor VIII concentrate is indicated. Side effects may include hepatitis and short-lived intravascular thrombin production.

Monitoring of bone resorption after renal transplantation by measuring the urinary excretion of pyridinium cross-links

The urinary excretion of pyridinium cross-links was measured in 70 second morning urine samples from 49 patients following renal transplantation. One and three months after renal transplantation, the urinary excretion of pyridinium cross-links was higher (p < 0.05) than at one week after transplantation. At all times after transplantation, the values for the excretion of pyridinium cross-links were correlated with the bone alkaline phosphatase concentrations (p < 0.001). However, there was no correlation between parathyrin concentrations and the values for the excretion of pyridinium cross-links (p > 0.05). This rise in the excretion of pyridinium cross-links is probably due to an increase of bone resorption caused by cyclosporin A and/or glucocorticoids. In the case of 17 urines with excretion values of pyridinium cross-links above the upper reference limit (pyridinoline equivalents, 93 mumol/mol creatinine), only 2 (12%) of the corresponding sera showed increased bone alkaline phosphatase values. In patients following renal transplantation simultaneous assessment of bone formation and bone resorption (determined from bone alkaline phosphatase serum concentrations and the excretion of pyridinium cross-links) may therefore enhance the diagnostic sensitivity for detecting effects on bone metabolism.

Optimisation of a new continuous UV assay for the determination of blood coagulation factor XIII activity in human plasma

The new photometric assay described by Fickenscher et al. (Thromb. Haemostas. 65 (1991) 535-540) for the determination of factor XIII facilitates the diagnosis of factor XIII deficiency. In spite of easy handling, this test should be used critically. Patients with hyperfibrinogenaemia showed factor XIII activities of less than 20%, whereas with an optimized assay we found normal factor XIII values. Also, the use of a fixed period of incubation for the analysis is questionable, because the period of constant reaction rate occurs earlier and is shorter with high factor XIII activities and later and longer with low factor XIII activities. A linear relation between factor XIII activity and signal only exists up to 80% of activity. In some plasma samples from patients with hyperfibrinogenaemia the factor XIII determination actually shows decreased values for factor XIII. During the reaction, a fibrin clot is formed. The resulting turbidity simulates an increase in absorbance so that NADH consumption is apparently decreased. In six patients with hyperfibrinogenaemia (8.1-9.4 g/l), a factor XIII activity of 26 U/l or less was determined. Using 50 microliters instead of 100 microliters sample volume, 50% (3/6) of the patients showed a normal factor XIII activities (80-96 U/l), whereas 50% (3/6) values of 6-15 U/l were found. In our modified assay we measured normal factor XIII activities (72-151 U/l) in all 6 patients. The procedure is optimized by reducing the sample volume from 100 microliters to 50 microliters.(ABSTRACT TRUNCATED AT 250 WORDS)

Monitoring of osteoblast activity with an immunoradiometric assay for determination of bone alkaline phosphatase mass concentration in patients receiving renal transplants

We examined the diagnostic validity of an immunoradiometric assay for determination of mass concentration of bone alkaline phosphatase (EC 3.1.3.1) in 134 sera from 35 patients receiving renal transplants. Comparison between bone alkaline phosphatase concentration and total alkaline phosphatase activity yielded a strong correlation (r = +0.860; P < 0.001). Nine (17%) of 54 sera which were characterized by a total alkaline phosphatase activity between 100 units/l and the upper reference limit (178 units/l (males) and 160 units/l (females), respectively) showed an increased bone alkaline phosphatase concentration (> 21.3 micrograms/l (males) and > 15.0 micrograms/l (females), respectively). There was also a correlation between bone alkaline phosphatase values and parathyroid hormone levels both before (r = +0.640 (n = 23), P < 0.001) and after renal transplantation (r = +0.528 (n = 111), P < 0.0001). A follow-up of 15 patients after renal transplantation revealed that the median of bone alkaline phosphatase values increased from 5.5 micrograms/l before transplantation to 14.9 micrograms/l 3 months after transplantation (P < 0.0001). Nevertheless no correlation could be observed between parathyroid hormone concentrations and bone alkaline phosphatase values at any time following renal transplantation in these 15 patients (P > 0.1). Rise of bone alkaline phosphatase concentration following renal transplantation is most probably due to an activating effect of cyclosporin A upon osteoblasts.

Efficacy of transferrin determination in human sera in the diagnosis of iron deficiency

Apparently healthy persons (n = 425) as well as 264 patients characterized by an iron concentration in serum < 7.2 mumol/l were examined. A latent iron deficiency was defined as a concentration of ferritin < 20 micrograms/l (males) and < 15 micrograms/l (females), without anaemia; manifest iron deficiency defined by an additional presence of hypochromic microcytic anaemia. Fifty-nine of 425 (= 14%) apparently healthy persons showed a latent iron deficiency. In the remaining 366 we established the following reference intervals for the concentration of transferrin in serum [mumol/l]: 25.2-45.3 (males), 29.1-54.5 (females, < or = 25 years of age) and 25.3-48.6 (females, > 25 years of age). Eight of 59 (= 14%) apparently healthy persons with latent iron deficiency had a transferrin concentration above the reference interval. Sixty-one of 264 (= 23%) patients with an iron concentration < 7.2 mumol/l showed a ferritin concentration < 20 micrograms/l (males) and < 15 micrograms/l (females). Thirty-eight of these 61 patients (= 62%) had a manifest iron deficiency. In 18 of these 38 patients (= 47%) the transferrin concentration was increased. For our 264 patients we determined the diagnostic validity of an increased transferrin concentration for diagnosis of iron deficiency, assuming an iron deficiency if the concentration of ferritin remained below the discrimination values mentioned above: The diagnostic sensitivity was 36%, the diagnostic specificity 97%, the predictive value of the positive test result 79% and the predictive value of the negative test result 83%.(ABSTRACT TRUNCATED AT 250 WORDS)

Nocturnal asthma: slow-release terbutaline versus slow-release theophylline therapy

In a double-blind cross-over study, the effects of slow release (S-R) terbutaline tablets (b.i.d. 0.25 mg/kg per day) and S-R theophylline (5.31 mg/kg morning and 10.62 mg/kg evening) were compared in eleven patients with nocturnal asthma. On day seven of each treatment period, drug serum concentrations and peak expiratory flow (PEF) were measured every 2h over a 24-h period. During daytime, terbutaline concentrations ranged from 1.6-14.1 (median 4.5) microgram/l and during the night from 2.1-18.7 (median 4.9) micron/l. Theophylline concentrations ranged from 3.9-24.3 (median 11.5) mg/l during the day and from 3.3-20.9 (median 10.4) mg/l at night. Nocturnal wheezing occurred during theophylline treatment in four patients 7 times and during terbutaline treatment in six patients 22 times. Daytime PEF values were 472 +/- 161 l/min during theophylline therapy versus 445 +/- 169 l/min during terbutaline therapy (p less than 0.05). In the night and early morning there was no significant difference between PEF values with the two treatment forms. During theophylline treatment, fewer inhalations of beta 2-sympathomimetics were used, and there were fewer side effects. One patient experienced severe asthmatic attacks during the terbutaline treatment period. The patients preferred theophylline for the treatment of nocturnal asthma.

Nocturnal asthma: slow-release terbutaline versus slow-release theophylline therapy

In a double-blind cross-over study, the effects of slow release (S-R) terbutaline tablets (b.i.d. 0.25 mg/kg per day) and S-R theophylline (5.31 mg/kg morning and 10.62 mg/kg evening) were compared in eleven patients with nocturnal asthma. On day seven of each treatment period, drug serum concentrations and peak expiratory flow (PEF) were measured every 2h over a 24-h period. During daytime, terbutaline concentrations ranged from 1.6-14.1 (median 4.5) microgram/l and during the night from 2.1-18.7 (median 4.9) micron/l. Theophylline concentrations ranged from 3.9-24.3 (median 11.5) mg/l during the day and from 3.3-20.9 (median 10.4) mg/l at night. Nocturnal wheezing occurred during theophylline treatment in four patients 7 times and during terbutaline treatment in six patients 22 times. Daytime PEF values were 472 +/- 161 l/min during theophylline therapy versus 445 +/- 169 l/min during terbutaline therapy (p less than 0.05). In the night and early morning there was no significant difference between PEF values with the two treatment forms. During theophylline treatment, fewer inhalations of beta 2-sympathomimetics were used, and there were fewer side effects. One patient experienced severe asthmatic attacks during the terbutaline treatment period. The patients preferred theophylline for the treatment of nocturnal asthma.

Treatment of nocturnal asthma: the role of sustained-release theophylline and oral beta-2-mimetics

In two double-blind, multiple-dose cross-over studies the therapeutic effects of SR theophylline preparations given once each night (mean 11.2 mg/kg per day) versus twice daily in equal doses (mean 10.3 mg/kg per day) (study I) and SR-terbutaline in equal doses (mean 0.25 mg/kg per day) versus SR theophylline in unequally divided daily doses (mean 5.3 mg/kg morning dose, 10.6 mg/kg evening dose) study II) were compared in 19 patients with nocturnal asthma. At the end of each treatment period drug serum concentrations and PEFR were measured every 2 hr over a 24-hr period. With the twice-daily, equally divided regimen, serum theophylline concentrations were lower at night than during the day (mean 9.4 +/- 0.9 versus 11.3 +/- 1.0 mg/l). With the single evening administration, serum theophylline concentrations were considerably higher at night (Cmax 16.3 +/- 1.4 mg/l) and the circadian variation of PEFR was significantly reduced. PEFR was higher during night and early morning (283 +/- 14 versus 217 +/- 11 l/min, P less than 0.005). During daytime in study II, PEFR values were slightly higher with theophylline than terbutaline. There was no significant difference in peak flow between either treatment during the night and early morning. However, additional use of inhaled beta-2-mimetics because of asthmatic attacks occurred more often during terbutaline (79 times in 8/10 patients) than theophylline treatment (29 times in 5/10 patients). Symptom scores, number of attacks and side-effects clearly favor the theophylline regimen. We conclude that for patients with nocturnal asthma a once-nightly dose of SR theophylline can be sufficient for stabilization of the airways.

Perceptions of medical school faculty members and students on clinical clerkship feedback

The authors in this study investigated faculty members' and students' perceptions of the feedback they provided or received, respectively, during the clerkships in all clinical departments at a university hospital. All faculty members who teach students in the clinical years and all third- and fourth-year medical students were surveyed. Respondents were asked to indicate, on a 7-point scale, the importance they attributed to eight feedback categories and to rate the frequency of actual feedback they felt was provided or received in these eight categories. The results indicate that while both faculty members and students perceived six of the eight feedback categories as equally important, they differed substantially in their ratings of the actual feedback provided or received.

Perceptions of medical school faculty members and students on clinical clerkship feedback

The authors in this study investigated faculty members' and students' perceptions of the feedback they provided or received, respectively, during the clerkships in all clinical departments at a university hospital. All faculty members who teach students in the clinical years and all third- and fourth-year medical students were surveyed. Respondents were asked to indicate, on a 7-point scale, the importance they attributed to eight feedback categories and to rate the frequency of actual feedback they felt was provided or received in these eight categories. The results indicate that while both faculty members and students perceived six of the eight feedback categories as equally important, they differed substantially in their ratings of the actual feedback provided or received.

Perceived stress in medical, law, and graduate students

Students in the medical and law schools and graduate students in chemistry and psychology at a single institution were asked to complete a questionnaire about events and activities related to their educational programs which they perceived to be stressful. The questionnaire was designed to elicit information about stress associated with academic activities, personal relationships, time pressures, and financial concerns. Information was also obtained about time utilization, health behaviors, crises, and support systems. The authors' hypothesis that medical students would report higher perceived stress levels than students in the other programs was not supported, as the highest total stress score was reported by law students. Factor analysis of a 31-item stress scale produced six separate factors pertaining to the sources of stress: academic concerns, time concerns, fear of failing, classroom interactions, economic issues, and world issues. Time restrictions and economic and academic issues had the highest mean stress scores. The hypotheses by the authors that students would report program-specific stresses and that utilization of support services would differ among the four groups of students were both supported. Implications of these findings are discussed.

Attitudes of pediatricians toward maternal employment

The largest number of women in history is employed outside the home including 55% of mothers with children less than 18 years of age. The attitudes of pediatricians toward employed mothers were assessed by a mail survey to the entire membership of the American Academy of Pediatrics. Usable responses were received from 5,758 pediatricians (31%). Adequacy of child care and economic necessity were ranked as the most important factors considered by responding pediatricians when advising a mother inquiring whether she should work outside the home. One third of the respondents stated the child can be any age when the mother becomes employed. The majority of respondents did not feel there was a difference between children of employed mothers and homemaker mothers. Special considerations for employed mothers were provided by half of the respondents, more frequently by female than male pediatricians. Most respondents are supportive of mothers working outside the home, but bias against employed mothers does exist. Pediatricians whose spouses do not work outside the home, those in older age groups, and male pediatricians tended to hold more traditional attitudes toward maternal employment.

Effect of immediate student evaluations on a multi-instructor course

Immediate student feedback and peer evaluation by a single physician were used to evaluate and monitor an interdisciplinary multi-instructor course. Clinical Correlations with Pathology is taught during the second year of medical school by 50 instructors, each of whom has a limited exposure to sophomore medical students. The format of the course, in which the same students evaluate multiple lecturers in multiple content areas, provided a unique opportunity to demonstrate the reliability and validity of student evaluations. About one-half of the lectures were repeated by the same instructors the following year to the next class of medical students, who also evaluated all of the lectures. Comparison of two consecutive sophomore classes of medical students documented overall course improvement and showed higher ratings given to instructors who presented the same lecture both years. Student evaluation is a powerful technique that can result in positive changes leading toward course improvement.