Effects of physical training on metabolic control in elderly type 2 diabetes mellitus patients

1. The specific role of physical activity in the treatment of type 2 diabetes is still subject to discussion. A randomized prospective study was performed, investigating both the influence of physical training on metabolic control and the feasibility of physical training in the elderly. 2. A total of 58 patients (mean age: 62 +/- 5 years; range: 55-75 years) with type 2 diabetes were randomized to either a physical training or a control programme. The training programme consisted of three sessions a week, aiming at 60-80% of the maximal oxygen uptake (VO2max). The 12 week supervised period was followed by a 14 week non-supervised one. The control group followed an educational programme. VO2max was assessed during exercise on a cycle ergometer. Glycosylated haemoglobin (HbA1c) was used as a measure for glucose control, and an insulin tolerance test was performed to test insulin sensitivity. Multivariate analysis of variance, with repeated measures design, was used to test differences between groups. 3. Fifty-one patients completed the study. VO2max was higher in the training group than in the control group both after 6 weeks (P < or = 0.01 between groups) and after 26 weeks [training group: 1796 +/- 419 ml/min (prestudy), 1880 +/- 458 ml/min (6 weeks), 1786 +/- 591 ml/min (26 weeks); control group: 1859 +/- 455 ml/min (prestudy), 1742 +/- 467 ml/min (6 weeks), 1629 +/- 504 ml/min (26 weeks)]. Blood glucose control and insulin sensitivity did not change during the study. Levels of total triacylglycerols, very-low-density lipoprotein-triacylglycerols and apolipoprotein B were significantly lower after 6 weeks (P < or = 0.01, P < or = 0.05, P < or = 0.05 between groups respectively), and so was the level of total cholesterol after 12 weeks of training (P < or = 0.05 between groups). 4. Physical training in obese type 2 diabetic patients over 55 years of age does not change glycaemic control or insulin sensitivity in the short-term. Regular physical activity may lower triacylglycerol and cholesterol levels in this group of patients. 5. Finally, physical training in motivated elderly type 2 diabetic patients without major cardiovascular or musculoskeletal disorders is feasible, but only under supervision.

Patients with diabetes mellitus and atherosclerosis; a role for cytomegalovirus?

Diabetic patients are known to have an impaired immune response to viral antigens and a high incidence of atherosclerosis. This study was initiated to evaluate the association between cytomegalovirus infection and atherosclerosis in patients with diabetes mellitus. Patients with diabetes mellitus type 1 and 2 (> 5 years) with (group A) and without (group B) clinical signs of atherosclerosis were included. Cytomegalovirus cultures were obtained, serum was screened for CMV-antibodies and CMV-IgG and CMV-IgM titers were determined. Cytomegalovirus antibodies were detected more often in diabetic patients with atherosclerosis compared to patients without atherosclerosis (70.7 vs. 45.2%, P = 0.018. In female patients the prevalence of CMV-antibodies was 89.5 vs. 40.0% (P = 0.0037). CMV IgG titers were twice as high in group A compared to group B. Cytomegalovirus was cultured from four urine samples and two throat swabs in group B and in one urine and one throat swab in group A. The prevalence of cytomegalovirus antibodies was higher in diabetic patients with atherosclerosis compared to diabetic patients without atherosclerosis. This difference was most striking in the female population. CMV-IgG titers were twice as high in the atherosclerosis group. These data suggest that cytomegalovirus may play a role in the development of clinical atherosclerosis in patients with diabetes mellitus.

Comparison of LysB28, ProB29-human insulin analog and regular human insulin in the correction of incidental hyperglycemia

OBJECTIVE

To obtain clinically applicable data on the effects of regular human insulin and the LysB28,ProB29-human insulin analogue (lispro) on the correction of incidental hyperglycemia.

RESEARCH DESIGN AND METHODS

The insulins were compared in a non-clamped randomized crossover study of 27 male IDDM patients. Hyperglycemia was induced by the withdrawal of the normal evening dose of insulin; the next morning patients fasted and received a single dose of study insulin according to a dosing nomogram. Blood glucose concentration and GR (a measure of glucose corrected for differences in administered insulin dose: GR = glucose concentration X BMI X insulin dose-1) were followed for 4 h.

RESULTS

The time courses of blood glucose concentration and GR were significantly different after regular insulin in comparison with lispro (multiple analysis of variance, P < 0.001). At t = 120 min, glucose concentrations had decreased 1.4 mmol/l more with lispro than with regular insulin (95% confidence interval [CI] 0.6-2.3, P = 0.002). Similarly, GR had decreased 4.4 mol.kg.IU-1.m-5 more with lispro than with regular insulin (95% CI 2.6-6.2, P < 0.001). The overall difference in glucose values was 0.87 mmol/l (lispro < regular insulin, P = 0.036), and the overall difference in GR values was 1.96 mol.kg.IU-1.m-5 (lispro < regular insulin, P = NS). Unexpectedly, the intrinsic variability of GR was higher for lispro than for regular insulin.

CONCLUSIONS

The more rapid action of lispro is an advantage in the correction of hyperglycemia, even though actual differences in glucose concentrations are smaller than suggested by previous clamped studies.

Smoking and diabetes mellitus

The goal of this review is to determine the effects of smoking on diabetes mellitus, whether it aggravates diabetic complications or influences insulin metabolism and action. Also available anti-smoking programmes applicable for diabetic patients have been studied. The prevalence of smoking among diabetic patients has been investigated by conducting a meta-analysis. Compared with normal subjects, the prevalence of smoking among diabetic patients is significantly higher (27 vs. 33%, p < 0.0001), IDDM patients largely accounting for this difference. However, care must be used in interpreting these data. Smoking presents an extra risk for development of macro- and microvascular complications in these patients, contributing to increased cardiovascular morbidity and mortality. Smoking also increases the risk of diabetes itself. Neither acute nor habitual smoking causes substantial changes in insulin sensitivity in IDDM patients, whereas it does so in NIDDM. Studies in diabetic patients concerning anti-smoking strategies are scarce and only yield disappointing results. Making these patients abstain from smoking turns out to be extremely difficult, probably due to the considerable psychosocial stress experienced.

High seroprevalence of Helicobacter pylori in diabetes mellitus patients

To assess the prevalence of Helicobacter pylori in diabetes mellitus, a serological test used to detect antibodies to H. Pylori in patients with diabetes mellitus. Within six months, 45 insulin-dependent, 98 non-insulin-dependent, and a control group of 159 outpatients were enrolled in this study. The age adjusted seroprevalence rate of Helicobacter pylori were determined using a commercial anti-Helicobacter pylori IgC and IgA ELISA (Bio-Rad). The prevalence rates increased with age in all age groups until 60-70 years. In diabetic patients, the frequency of Helicobacter pylori infection was higher than control subjects in nearly all age groups, reaching significance in three age categories of NIDDM patients and in one age category in IDDM patients. This higher seroprevalence could not be explained by differences in socioeconomic status or use of antibiotics.

Extremely elevated body temperature: case report and review of classical heat stroke

Classical heat stroke is a rare disease in moderate climates. We report a patient who demonstrated the classical triad of elevated body temperature, neurological disturbances, and anhidrosis. He developed rhabdomyolysis and acute renal failure. Eventually he died. Since manifestations of classical heat stroke appear to mimic an acute phase response, cytokines are thought to play an important role in its pathogenesis.

Postprandial reversal of the portal venous flow in a patient with liver cirrhosis

The case of a 61-year-old man with alcoholic liver cirrhosis and a hepatocellular carcinoma is presented. He was examined with duplex Doppler before and after a meal. In the fasting state a sluggish hepatopetal portal venous flow was found. After the meal a pendulating flow and then hepatofugal flow were found. The magnitude and direction of flow alternated synchronously with the action of the heart, suggesting a significant role for the hepatic artery in the postprandial reversal of portal venous flow. One year after this examination the patient died from the complications of decompensated cirrhosis and liver failure. At autopsy a large hepatocellular carcinoma was detected.

Evaluation of fine needle aspiration (FNA) cytology in the diagnosis of thyroid nodules

FNA cytology of 112 patients with thyroid nodules seen in a 5-year period in a general hospital setting, and the histology obtained from the 53 operated patients, were retrospectively analysed. The inadequacy rate of FNA cytology was 11%, sensitivity was 84% (16/19), specificity was 52% (15/29), positive predictive value was 53% (16/30) and negative predictive value was 83% (15/18). Extrapolating these figures to the whole study group a negative predictive value of 95% is put forward as a more realistic figure. The results and the clinical pitfalls of the use of FNA cytology in diagnosing thyroid nodules are discussed. The authors conclude that FNA cytology is a reliable first diagnostic step in the diagnosis of thyroid nodules, even in a general hospital setting.

Magnesium therapy in acute myocardial infarction

The trials reviewed in this study investigated the effect of intravenous magnesium on arrhythmias and mortality in acute myocardial infarction. Nine trials were carried out in the pre-thrombolytic era. They varied in set-up, number of patients, dose of magnesium, follow-up and the type of arrhythmias analyzed. Magnesium reduced mortality in most studies, but the reduction was significant in only three of them. Two meta-analyses of the smaller studies revealed a 55% reduction in mortality. In the LIMIT-2, in which 2300 patients were enrolled, magnesium reduced mortality significantly by 24%. The effect of magnesium on arrhythmias was less clear. Preliminary results of ISIS-4, in which magnesium among others was administered together with thrombolytic agents, did not provide evidence of benefit in patients with suspected myocardial infarction. At present there are no arguments for the use of magnesium in acute myocardial infarction.

Blunted postprandial reaction of portal venous flow in chronic liver disease, assessed with duplex Doppler: significance for prognosis

To establish the effects of a meal on portal venous flow and the prognostic value of this parameter, 46 patients with chronic liver disease and 28 healthy subjects were examined with duplex Doppler before and after a meal. The measurements were completed in 40 patients and 21 healthy subjects. Postprandial portal venous diameter, blood velocity and quantitative flow were measured for 60 min. Mean baseline values were: 11.4 mm versus 10.2 mm (p = 0.019), 10.8 cm.s-1 versus 13.4 cm.s-1 (p = 0.015) and 668 ml.min-1 versus 646 ml.min-1 (p = 0.7) respectively. Spleen size was 15.0 cm versus 10.6 cm (p = 0.0001) respectively. Postprandial diameter, velocity and flow increased significantly in patients and controls (p = 0.0001 for all). Mean postprandial flow could best be described by a polynomial equation with a parabolic curve. Patients' curves were more blunted than controls', with significantly different regression constants (p = 0.025 and p = 0.029). All subjects were followed up for survival and variceal haemorrhage. The mean follow-up time was 47 months. Early maximum postprandial velocity (p = 0.041) and large spleen size (p = 0.002) were significantly related to an unfavourable prognosis for survival. Early maximum velocity was also related to increased variceal haemorrhage. This study shows that postprandial portal venous flow is blunted in patients with chronic liver disease. Postprandial portal venous flow may have prognostic significance.

Hypoglycaemia unawareness

Hypoglycaemia is a severe complication of insulin-dependent diabetes mellitus, especially when it is not preceded by warning signs. A patient unaware of a low blood glucose concentration may not take any remedial action, becomes severely hypoglycaemic and may lapse into a potentially fatal coma. Hypoglycaemic unawareness is associated particularly with good glycaemic control. Hypoglycaemia unawareness was first related to diabetic autonomic neuropathy. Subsequently it emerged that well controlled diabetic patients suffered from hypoglycaemia unawareness more often than poorly controlled patients. Next to autonomic neuropathy and good glycaemic control, the transfer of more slowly resorbed beef and porcine insulin to more rapidly resorbed human insulin has been incriminated as causing an increased incidence of hypoglycaemia unawareness. Reviewing the scientific literature concerning the connection between hypoglycaemia unawareness and the use of human insulin, there is no rationale for supporting the hypothesis that human insulin leads to hypoglycaemia unawareness any longer. While the pathophysiology of hypoglycemia unawareness remains unclear in patients with insulin-dependent diabetes mellitus of long duration, it may well be related to impaired adrenaline secretion. The cause of this impaired adrenaline secretion during hypoglycaemia is unknown and it does not seem to be a result of diabetic autonomic neuropathy.

Portal venous flow and follow-up in patients with liver disease and healthy subjects. Assessment with duplex Doppler

The evolution of portal venous flow in non-end-stage chronic liver disease with portal hypertension was assessed in 59 patients and compared with that in 55 control subjects and by means of duplex Doppler measurements by a single observer. All patients were prospectively followed up, and a repeated measurement was performed in a subgroup of 23 patients. The mean (+/- SD) portal venous diameter and velocity of patients versus controls were 11.2 (+/- 2.0) mm versus 10.1 (+/- 1.4) mm (p < 0.0005) and 11.0 (+/- 4.2) cm/sec versus 13.9 (+/- 4.1) cm/sec (p < 0.0005). The portal venous flow did not differ: 671 (+/- 291) ml/min versus 652 (+/- 203) ml/min. Diagnosis, Child class, and grade of varices did not influence the portal flow. Patients were followed up during a median (+/- SD) time of 47 (+/- 17) months. Nineteen (32%) patients died, and 14 (23%) had a variceal hemorrhage. Survival and hemorrhage were not correlated with the portal venous flow. Subsequent measurements in 23 patients showed a significant decrease in portal venous flow in 5 patients who died during follow-up. This was not found in the patients who survived. It is concluded that portal venous flow in chronic liver disease with portal hypertension is stable for a long time in the evolution of chronic liver disease. The existence of a 'portostat' is postulated. Only in the terminal stage of liver disease can a reduction of the portal venous flow be detected.

Influence of blood glucose levels on peripheral lymphocytes in patients with diabetes mellitus

Abnormalities in lymphocyte subpopulations in patients with type 1 diabetes have been reported previously. To evaluate the effect of blood glucose levels on peripheral lymphocyte concentrations we studied the proportion and phenotypic composition of the T-cell population in 7 patients with type 1 and in 12 patients with type 2 diabetes at hospitalization because of metabolic dysregulation and in a period of restored control. Both the number of CD-4 and CD-8 positive cells increased significantly (p < 0.05), although no change in the CD-4:CD-8 ratio was observed. After restoring metabolic control there was a significant rise in the mean number of total lymphocytes (1760 +/- 759 x 10(6)/ml vs 2385 +/- 889 x 10(6)/ml, p < 0.05). The number of total lymphocytes increased in all patients but one. It is concluded that metabolic control can influence immunological parameters such as numbers of peripheral lymphocytes of various phenotypes.

Humoral immune response to a yeast-derived hepatitis B vaccine in patients with type 1 diabetes mellitus

The immune response following vaccination with a recombinant hepatitis B vaccine was investigated in 32 patients with Type 1 diabetes mellitus and compared with the outcome in 32 healthy age- and sex-matched volunteers. Participants were vaccinated at 0, 30, and 180 days and in vivo immune response was determined at 30, 60, 90, 180, and 210 days. The number of responders (anti-HBs greater than 1 IU l-1) was significantly lower (p less than 0.05) among patients at 30 (2 vs 11), 60 (17 vs 26), 90 (20 vs 28) and 180 (22 vs 29) days. The number of patients protected (anti-HBs greater than 10 IU l-1) was lower (p less than 0.05) than the number of protected volunteers at 60 (5 vs 14), 90 (10 vs 19), 180 (15 vs 24), and 210 days (24 vs 31). After the complete course of vaccination 8 out of 32 patients were still unprotected against hepatitis B (p less than 0.05). The anti-HBs titre of responders at 210 days was 251 (20, 3162) (geometric mean (-SD, +SD] IU l-1 in patients and 1259 (126, 12589) IU l-1 in control subjects (p less than 0.05). The HLA-antigen DQw1 frequency in the diabetic low responders (anti-HBs less than 100 IU l-1) was 0.27 compared with 0.86 in diabetic adequate responders. No relation between anti-HBs production and concentration of HbA1c could be demonstrated.

Duplex Doppler measurements of portal venous flow in normal subjects. Inter- and intra-observer variability

We investigated the variability of quantitative duplex Doppler measurements of portal flow. Measurements were validated in vitro using a flow phantom. The measured flow Q (ml/min), is related to the actual phantom output P (ml/min) according to the following formula: Q = 1.08 (P + 44) (r = 0.998). To estimate inter- and intra-observer variance, 38 subjects without portal hypertension were examined in two groups. Two observers examined the first group of subjects (n = 19), from a routine daily ultrasound schedule. Significant differences were found in mean +/- S.D. portal flow (692 +/- 182 ml/min vs. 613 +/- 185 ml/min, p = 0.04) and mean +/- S.D. velocity (15.3 +/- 3.9 cm/s vs. 13.2 +/- 2.6 cm/s, p = 0.01). The combined inter- and intra-observer coefficient of variation (S.D.) was 24% (158 ml/min), 9% (0.92 mm) and 24% (3.4 cm/s) for portal flow, diameter and velocity respectively. Non-systematic components of variance were the largest. Patient characteristics, age, sex, height, weight and body surface area did not influence measurement variations. In the second group of healthy volunteers (n = 19), where variance in measurements over 3 consecutive days was comparable to the combined variance in the first group, the non-systematic variance component was also the largest. We conclude that quantitative duplex Doppler measurements of portal venous flow are mainly subject to non-systematic variability. A coefficient of variation of 24% can be expected in diagnostic measurements in a single patient. Examination by a single observer is advisable. The value of this technique lies in the analysis of pathophysiological mechanisms in portal flow changes in large groups of subjects.