Association of differing dietary, metabolic, and clinical risk factors with macrovascular complications of diabetes: a prevalence study of 503 Mexican type II diabetic subjects. I

Useful screening tools for preventing foot problems of diabetics in rural areas: a cross-sectional study

BACKGROUND

Preventing diabetic foot problems (DFP) and their associated consequences is a critical in rural regions. The objective is to present an association of non-invasive DFP assessment tools and physiological indicators for early detection among rural cases of diabetes in Taiwan.

METHODS

Secondary data analysis of 387 participants previously diagnosed with type 2 diabetes was used. The Michigan Neuropathy Screening Instrument (MNSI), Ankle Brachial Index (ABI), optimal scaling combination (OSC) of MNSI, and age were used to examine peripheral neurovascular function. The King's College classification (KC) and Texas risk classification (TRC) were used to understand diabetic foot complications.

RESULTS

The findings indicated that MNSI was negatively correlated with ABI, but positively with diabetes duration, age, KC, TRC, fasting blood glucose, low density of lipoprotein cholesterol, body mass index and waist circumference. The area under the receiver operating characteristic curves for assessing the risk of ABI based on OSC was larger than for MNSI, KC, and TRC.

CONCLUSION

It is shown that using OSC, MNSI, and ABI as community screening tools is useful in detecting early neurovasculopathy. In addition, where an ABI machine is unavailable, primary healthcare providers that perform MNSI or OSC may be cost-effective. The study was approved by the institutional review board of the ethical committee (No 98-2224-B).

The prevalence of peripheral arterial disease in korean patients with type 2 diabetes mellitus attending a university hospital

BACKGROUND

Peripheral arterial disease (PAD) is a common manifestation of systemic atherosclerosis and is associated with significant morbidity and mortality. Diabetes is known to increase the risk of PAD two- to four-fold. The prevalence of PAD in Korean diabetic patients has not been established. In this study, we investigated the prevalence of PAD in Korean patients with type 2 diabetes attending a large university hospital and analyzed the factors associated with PAD.

METHODS

A total of 2,002 patients with type 2 diabetes who underwent ankle-brachial index (ABI) measurement in an outpatient clinic were enrolled. PAD was defined as an ABI ≤0.9. Clinical characteristics of 64 patients with PAD were compared with those of 192 age- and sex-matched control patients without PAD.

RESULTS

Of the 2,002 type 2 diabetic patients, 64 (3.2%) were diagnosed as having PAD. PAD was associated with higher prevalences of retinopathy, nephropathy, neuropathy, cerebrovascular and coronary artery disease. Patients with PAD had higher systolic blood pressure and serum triglyceride level and reported higher pack-years of smoking. Multivariate analysis showed that the presence of micro- and macrovascular complications and high systolic blood pressure are factors independently associated with PAD.

CONCLUSION

The prevalence of PAD in diabetic patients was 3.2%, suggesting that the prevalence in Korean diabetic patients is lower than that of patients in Western countries.

The relative effect of self-management practices on glycaemic control in type 2 diabetic patients in Mexico

OBJECTIVE

In this study, we examined the relative impact of self-management activities on glycaemic control in a population at high risk for developing complications.

METHODS

Patients diagnosed with diabetes mellitus of at least 1 year in duration at 30 years of age or older were sampled from the Instituto de Mexico Seguro Social (IMSS) Family Medicine Clinics in Guadalajara, Mexico (n=800). Demographic, clinical and health behaviour variables were used to predict good/poor glycaemic control, as measured by haemoglobin Alc (A1C).

RESULTS

Most (72.24%) patients had poor control (A1C > or = 7.0). Hyperglycaemia was significantly associated with factors not under patient control, such as having diabetes for a longer time [odds ratio (OR) = 2.40, 95% confidence interval (CI) 1.39, 4.14], having a first-degree relative with diabetes (OR= 1.52; 95% CI 1.06, 2.19), and being prescribed anti-diabetic medications, e.g. insulin (OR = 7.88, 95% CI 2.42, 25.63). After controlling for these variables, the only self-management variable that reduced the likelihood of hyperglycaemia was following a special diet (OR=0.49; 95% CI 0.32, 0.76). Furthermore, depression had an important effect on self-management, as those with lower levels of depressive symptoms were more likely to follow a diet and exercise.

DISCUSSION

While patients in this population have little control over many factors associated with glycaemic control, an important exception is diet. However, because of the adverse effect of depression on dieting, both depression management and dietary education are important for this population.

Association of glucose metabolism, smoking and cardiovascular risk factors with incident peripheral arterial disease: the DESIR study

AIMS

We determined the 6-year incidence of peripheral arterial disease (PAD) in a French population and assessed the association of glucose metabolism, smoking, cardiovascular risk factors and physical activity with incident PAD.

METHODS

Participants from the French Data from a Epidemiological Study on the Insulin Resistance Syndrome (DESIR) were studied. Participants analysed were 30-65 years (at baseline) and had complete data (n=3805) after 6 years of follow-up. Diabetes was diagnosed according to the 1999 WHO criteria on the basis of fasting plasma glucose results or previous diagnosis of diabetes mellitus. The ankle brachial pressure index (ABPI) and a claudication question were used to classify PAD.

RESULTS

The 6-year incidence of PAD (defined by ABPI<0.9 and or claudication present) among those with normal fasting glucose (NFG) and free of PAD at baseline was 5.1%. Among those with impaired fasting glucose (IFG) at baseline the incidence of PAD was 4.9% and among those with diabetes mellitus at baseline the incidence of PAD was 9.8%. The incidence of PAD among those who maintained NFG over 6 years was 4.7% and among those who progressed to diabetes over 6 years was 10.2%. Those who progressed from NFG or IFG to diabetes over 6 years were twice as likely to develop PAD compared to those who maintained NFG over 6 years, after adjustment for age and sex (OR (95% CI), 2.22 (1.12-4.42)). Independent risk factors for incident PAD using baseline population characteristics were diabetes (OR (95% CI) 2.11 (1.25-3.55)), systolic BP 122-135mmHg 1.06 (0.70-1.60), >135mmHg 1.54 (1.04-2.27) and current smoking 1.60 (1.10-2.34) after multivariate adjustment for age, sex, cholesterol, triglycerides and waist circumference.

CONCLUSIONS

This French study shows that those who progress to diabetes are twice as likely to develop PAD, compared to those who maintain NFG. Peripheral arterial disease is a treatable condition and more aggressive management of atherosclerotic risk factors could reduce the numbers of people who develop PAD.

Blink reflex alterations in recently diagnosed diabetic patients

OBJECTIVE

The aim of the present study was to determine the frequency of blink reflex alterations and to examine the influence of hyperglycemia in inducing the alterations in recently diagnosed Type 2 diabetes mellitus patients.

METHODS

A cross-sectional study was carried out on patients having asymptomatic diabetes with a period of evolution under 10 years. In all 47 patients (26 women and 21 men), serum glycemia levels were determined and the latency onset of the blink reflex components were measured.

RESULTS

The average patient age was 44.5+/-11.0 (mean+/-SD) years with a diabetes evolution period of 4.3+/-2.9 (mean+/-SD) years. After a fasting serum glucose test, the diabetic patients were catalogued as normoglycemic (< or =126 mg/dl) or as hyperglycemic (> 26 mg/dl) and subjected to a blink reflex test. The results obtained from the diabetic patients were compared with those from a non-diabetic control group. 14.8-31.9% of the diabetic patients showed alterations in blink reflex component latencies. The differences compared with the control group were significant (p<0.05).

CONCLUSIONS

Diabetes, as is well-known, can affect the central and peripheral nervous system and there does not appear to be a link between glycemic levels and blink reflex components. However, blink reflex alterations were present even in diabetic patients with a relatively short period of disease evolution.

Cost-effectiveness of glycemic control and ophthalmological care in diabetic retinopathy

AIMS

Glycemic control and ophthalmological care are known to significantly diminish the risk of visual impairment and blindness by diabetic retinopathy (DRP). The (cost-)effectiveness of both strategies was studied to highlight their benefits for patients and care providers.

METHODS

A computer analysis was developed, following the progression of DRP and the effectiveness of metabolic control and ophthalmological care continuously and individually in cohorts of type I and type II DM patients with divergent degrees of compliance. Costs relate to present medical charges in the Netherlands.

RESULTS

Intensive glycemic control shortens the duration of blindness in a type I DM patient by 0.76 years, intensive ophthalmological care by 0.53 years. One year sight gain may cost 1126 euros by providing ophthalmological care and 50479 euros by glycemic control. The duration of blindness drops in a type II DM patient by 0.48 and 0.13 years, respectively, whereas the effectiveness decreases as the age of onset of DM rises.

CONCLUSIONS

The vast majority of diabetic patients benefits from both intensive glycemic control and intensive ophthalmological care, but these cost-effective interventions which are not only complementary, but also substitute each other, require lasting, full compliance by all parties concerned.

Foot complications in Type 2 diabetes: an Australian population-based study

AIMS

To determine the prevalence and risk factors for neuropathy and peripheral vascular disease (PVD) in the Australian diabetic population and identify those at high risk of foot ulceration.

METHODS

The Australian Diabetes Obesity and Lifestyle study included 11 247 adults aged >or= 25 years in 42 randomly selected areas of Australia. Neuropathy and PVD were assessed in participants identified as having diabetes (based on self report and oral glucose tolerance test), impaired fasting glucose, impaired glucose tolerance and in a random sample with normal glucose tolerance (total n = 2436).

RESULTS

The prevalence of peripheral neuropathy was 13.1% in those with known diabetes (KDM) and 7.1% in those with newly diagnosed (NDM). The prevalence of PVD was 13.9% in KDM and 6.9% in NDM. Of those with diabetes, 19.6% were at risk of foot ulceration. Independent risk factors for peripheral neuropathy were diabetes duration (odds ratio (95% CI) 1.73 (1.33-2.28) per 10 years), height (1.42 (1.08-1.88) per 10 cm), age (2.57 (1.94-3.40) per 10 years) and uric acid (1.59 (1.21-2.09) per 0.1 mmol/l). Risk factors for PVD were diabetes duration (1.64 (1.25-2.16) per 10 years), age (2.45 (1.86-3.22) per 10 years), smoking (2.07 (1.00-4.28)), uric acid (1.03 (1.00-1.06) per 0.1 mmol/l) and urinary albumin/creatinine ratio (1.11 (1.01-1.21) per 1 mg/mmol).

CONCLUSIONS

The prevalence of neuropathy and PVD was lower in this population than has been reported in other populations. This may reflect differences in sampling methods between community and hospital-based populations. Nevertheless, a substantial proportion of the diabetic population had risk factors for foot ulceration.

Efficacy and safety of rosiglitazone plus metformin in Mexicans with type 2 diabetes

BACKGROUND

Type 2 diabetes is a growing problem in Mexico. The present study was undertaken to evaluate the efficacy and safety of rosiglitazone 2 mg or 4 mg twice daily (bd) in combination with metformin 2.5 g/day in Mexican patients whose type 2 diabetes was inadequately controlled with metformin alone.

METHODS

This randomized, double-blind, placebo-controlled study was conducted at four centers in Mexico. A total of 116 patients were randomized to metformin 2.5 g/day plus placebo (n=39), metformin 2.5 g/day plus rosiglitazone 2 mg bd (n=37), or metformin 2.5 g/day plus rosiglitazone 4 mg bd (n=40) for 26 weeks.

RESULTS

Mean hemoglobin A(1c) (HbA(1c)) levels decreased significantly from baseline to Week 26 in the rosiglitazone 2 mg bd (-0.7%; p=0.0052) and 4 mg bd (-1.2%; p=0.0008) groups, but increased in the placebo group (+0.3%; p=0.2651). Mean fasting plasma glucose and fructosamine levels also improved significantly with metformin plus rosiglitazone therapy in a dose-ordered manner compared with placebo (p<or=0.0019 and p=0.0006, respectively). C-peptide and immunoreactive insulin levels were decreased from baseline in both rosiglitazone groups. Although mean increases in total cholesterol, low-density lipoprotein (LDL)-cholesterol, and high-density lipoprotein (HDL)-cholesterol were observed in the rosiglitazone groups, the total cholesterol:HDL-cholesterol ratio remained unchanged. The proportion of patients with one or more adverse events was similar across all three groups. There were no cases of hepatotoxicity.

CONCLUSION

Addition of rosiglitazone 2 mg bd and 4 mg bd to metformin therapy improved glycemic control in Mexican patients whose type 2 diabetes was inadequately controlled by metformin alone. Furthermore, the combination of rosiglitazone plus metformin was well tolerated.

Postprandial impairment of resistance vessel function in insulin treated patients with diabetes mellitus type-2

Reduced postischaemic reactive hyperaemia, is considered a marker of impaired resistance vessel function. Acute postprandial hyperlipidaemia has been shown to induce vascular dysfunction. In the present study, the impact of postprandial hyperglycaemia on resistance vessel reactivity was investigated in insulin treated type-2 diabetic patients. The study was performed in 16 insulin treated type-2 diabetics (eight male/eight female, age 47 +/- 3 years, HbA1c 7.2 +/- 0.2) and 16 controls. Reactive hyperaemia was measured in the forearm by venous occlusion plethysmography after 5 min of ischaemia in the fasting state and 90 min after a test meal. In diabetics, blood glucose increased from 8.7 +/- 1.1 to 15.3 +/- 1.0 mmol l-1 (P<0.001) postprandially. This resulted in (i) a significant increase of resting blood flow (3.4 +/- 0.3 to 4.8 +/- 0.4 ml min-1 100 ml-1, P<0.01) and (ii) in a reduced peak reactive hyperaemia (52.3 +/- 7.4 to 36.8 +/- 4.3 ml min-1 100 ml-1, P<0.005). In controls, a similar effect of the meal on resting flow was observed but reactive hyperaemia was unaltered. In the absence of a test meal, basal flow as well as peak reactive hyperaemia remained unchanged in diabetic as well as in non-diabetic subjects. Our data provide evidence that in the postprandial state resistance vessel reactivity becomes reduced in insulin treated type-2 diabetic patients.

Epidemiologic study of type 2 diabetes in Taiwan

Diabetes mellitus (DM) in adults is a global health problem, although its prevalence varies widely between different populations and the rate has generally increased worldwide. In Taiwan, the mortality rate from DM has almost doubled over the past 10 years. The prevalence of DM in Taiwan was established between 1985 and 1996 and the rates were between 4.9 and 9.2%. The prevalence of impaired glucose tolerance (IGT) was 15.5% (men 15% and women 15.9%). The prevalence of DM and IGT increased significantly with age for both genders. The significant factors associated with newly diagnosed DM were age, BMI, family history of DM, systolic blood pressure (hypertension), physical activity and serum triglyceride levels. The prevalence of large vessel disease (LVD) in DM and non-diabetic subjects were 20.0 and 12.9%, respectively. Among diabetics, 15.8% had ischemic heart disease (IHD), 1.7% leg vessel disease (leg VD), and 2.5% stroke. In non-diabetics, the prevalence of the aforementioned macroangiopathies were 11.5, 0.2 and 1.2%, respectively. The diabetics had a significantly higher prevalence of macrovascular disease than non-diabetic subjects. The most significantly associated with the LVD was serum cholesterol levels. Serum cholesterol and HbA1(c) were significantly associated with the development of IHD. Cigarette smoking and female gender were significantly associated with the leg VD. The prevalence of diabetic retinopathy (DR) was 35.0%. (background DR 30%, preproliferative DR 2.8% and proliferative DR 2.2%, respectively.) The prevalence of DR for previously and newly diagnosed diabetics were 45.2 and 28.3% (men 42.8 vs. 33.3% and women 47.5 vs. 24.8%), respectively. From multiple logistic regression analysis, duration of DM was the most important risk factor related to DR. Diabetic subjects treated with insulin had a higher risk of developing retinopathy than those treated with dietary control. The prevalence of nephropathy and neuropathy were 12.9 and 23.5%, respectively. For those patients with and those without nephropathy and neuropathy, the duration of DM, percentage of insulin treatment, percentage of hypertension, and fasting plasma glucose were significantly different. Diabetic duration, hypertension, insulin treatment and glycemic control consistently correlated with nephropathy and neuropathy. In conclusion, the prevalence of DM in Taiwan was between 4.9 and 9.2%, and the prevalence of IGT was 15.5%. The possible risk factors of newly diagnosed diabetes were age, family history of DM, BMI, SBP (hypertension), physical activity and triglyceride levels. Diabetes in Chinese subjects share many characteristics similar to other Asian populations. The burden imposed by the chronic complications of diabetes is massive. In Taiwan, the mortality rates from DM have increased greatly over the past 10 years. Reduction of the modificable risk factors such as BMI, hypertenion and dyslipidemia, and increase of physical activity and good glycemic control through public health efforts may help to reduce the risk of DM and its chronic complications.

Determinants of post-ischaemic reactive hyperaemia in patients with diabetes mellitus type II

Dysfunction of resistance arteries is thought to be an early reversible stage in the development of atherosclerosis. Dynamics of post-ischaemic reactive hyperaemia are believed to constitute a useful tool for monitoring resistance vessel function. Patient characteristics influencing reactive hyperaemia, however, need to be defined more precisely. Since reactive hyperaemia is a dynamic process, yielding submaximal peak values after 5 min of ischaemia, this period was chosen to investigate the determinants of reactive hyperaemia in 100 type II diabetic patients as well as in 61 control subjects. Reactive hyperaemia was measured by venous-occlusion plethysmography; clinical and laboratory data were acquired by routine methods. Statistical comparison was performed with SYSTAT 5.0 for Apple Macintosh. Overall, no significant differences between diabetic patients and controls were observed by group comparison. In control subjects, only gender showed an influence on peak reactive hyperaemia (females 40.5 +/- 15.3; males 51.8 +/- 17.7 ml min-1 100 ml-1, P < 0.01). In diabetic patients, in addition to gender, actual blood glucose (r = 0.377, P < 0.05) and meal intake (non-fasting 42.8 +/- 19.2; fasting 51.2 +/- 19.5 ml min-1 100 ml-1, P < 0.05) were found to influence reactive hyperaemia. Further investigation revealed a loss of the correlation between peak reactive hyperaemia and actual blood glucose observed in the fasting state (P < 0.001) in non-fasting diabetic patients, indicating an influence of meal intake on resistance vessel reactivity. Our results suggest that, in diabetic subjects, in addition to gender actual blood glucose and the postprandial situation impacts on peak reactive hyperaemia.

The role of haematological factors in diabetic peripheral arterial disease: the Edinburgh artery study

The relationship between haematological factors and peripheral arterial disease (PAD) among diabetics has not been widely examined. 1592 men and women aged 55-74 years were selected from the general population. They underwent an assessment for PAD and a glucose tolerance test. 288 subjects (18.7%) were identified as having diabetes or impaired glucose tolerance (IGT). Among the diabetes/IGT group, median levels of fibrinogen, von Willebrand factor (VWF), tissue plasminogen activator (t-PA), fibrin D-dimer and plasma viscosity were higher in subjects with PAD than those without PAD (P </= 0.05). The prevalence of PAD was higher in those with diabetes/IGT (20.6%) compared to those with normal glucose tolerance (12.5%) (odds ratio 1.64; 95% CI 1.17, 2.31). After separate adjustment for fibrinogen, VWF, t-PA, fibrin D-dimer, leucocyte elastase, plasma viscosity and haematocrit, those with diabetes/IGT no longer had a significantly higher risk of PAD compared to those with a normal glucose tolerance test. Simultaneous adjustment for the first four of these haematological factors reduced the risk of PAD among subjects with diabetes/IGT to 1.11 (95% CI 0.76, 1.63). Increased levels of haemostatic factors may partly explain the higher prevalence of PAD in diabetic/IGT subjects compared to normal glucose-tolerant subjects. Future randomized controlled trials involving the indirect lowering of levels of haematological factors should help to explain whether the associations reported here are of causal significance.

Relationship of microalbuminuria with the diabetic foot ulcers in type II diabetes

Microalbuminuria is a significant risk factor associated with nephropathy, retinopathy, and cardiovascular disease; however, there are no previous reports on the relationship of microalbuminuria with diabetic foot ulcers or stroke, despite the fact that microalbuminuria is a marker of vascular damage. The purpose of this study was to determine the relationship of microalbuminuria with diabetic foot ulcers in type II diabetes patients. In this, cross-sectional clinical study, outpatients of the offices at first level medical care in Durango, Mexico, were included in one of two groups; (a) patients with diabetic foot ulcers and (b) control of group patients without diabetic foot ulcers. Diabetic foot diagnosis was established on the basis of clinical criteria and pletismography. Patients diagnosed with renal disease, urinary tract infection, acute febrile illness, or heart failure and those receiving angiotensin-converting enzyme inhibitors were excluded from the study. Microalbuminuria was measured, on a 24-h urine collection, by precipitation with sulfasalicylic acid, and turbidity was determined by measuring absorbance with a spectrophotometer. The study included 670 diabetic patients. Using both odds ratio and logistic regression analyses, diabetes duration, cigarette smoking, aging, and microalbuminuria showed a strong relationship with diabetic foot ulcers. Microalbuminuria should be considered as an independent risk factor for diabetic foot ulcers.

Intracellular mechanism of high D-glucose-induced modulation of vascular cell proliferation

Development of atherosclerosis in diabetes patients is thought to be associated with high D-glucose-induced changes in vascular cell proliferation. This study was designed to investigate the intracellular mechanisms of altered proliferation in porcine aortic endothelial and smooth muscle cells under high D-glucose conditions. Two different technical approaches were used for determination of cell proliferation, a cell counting procedure and bromodeoxyuridine incorporation. D-Glucose diminished endothelial cell proliferation (30.3%) and increased smooth muscle cell proliferation (143%) in a dose-dependent manner. Neither D-mannitol, sucrose nor L-glucose mimicked the effect of D-glucose. Inhibition of D-glucose uptake into vascular cells by cytochalasin B prevented the effect of high D-glucose on cell proliferation. The aldose-reductase inhibitors, sorbinil and zopolrestat, little affected high D-glucose-attenuated endothelial cell proliferation, while the enhanced proliferation of smooth muscle cells was prevented by aldose-reductase inhibitors. Elevation of cellular glutathione levels yielded protection of both cell types from high D-glucose-mediated changes in cell proliferation, suggesting that high D-glucose may act via generation of oxidative species. Finally, aminoguanidine was shown to constitute a very potent inhibitor of D-glucose-induced dysfunction in vascular cell proliferation. These data suggest that high D-glucose-induced changes in cell proliferation of endothelial and smooth muscle cells are related to specific D-glucose uptake rather than hyperosmolality. Aldose-reductase seems to be mainly involved in the effect of high D-glucose only on smooth muscle cell proliferation, while in endothelial cells there is (are) other factor(s) in addition to the sorbitol pathway involved in high D-glucose-induced changes in cell proliferation.

Restoration of myo-inositol uptake by eicosapentaenoic acid in human skin fibroblasts cultured in high-glucose medium

The effects of elevated glucose and eicosapentaenoic acid (EPA, C20:5 omega 3) on myo-inositol uptake in human skin fibroblasts (HSF) were evaluated. Myo-inositol incorporation into HSF was dependent on an active transport system via Na(+)-K+ ATPase activity based on the results with Na+ deprivation and ouabain (5 mM). Although glucose (27.5, 55 mM) inhibited 2-[3H] myo-inositol uptake, the addition of EPA (3 x 10(-4) M) prevented glucose-mediated inhibition. Since EPA decreased glucose-mediated inhibition of myo-inositol uptake, this agent might ameliorate some of the devastating functions associated with diabetes.

Cholesterol rich apo B containing lipoproteins and smoking are independently associated with macrovascular disease in normotensive NIDDM patients

A cross-sectional study of macrovascular disease (MVD) and associated metabolic and other risk factors was conducted in 87 normotensive NIDDM patients. MVD was assessed by Rose questionnaire, 12 lead resting ECG, duplex scanning of carotid and peripheral vessels, and ankle:brachial systolic blood pressure ratio. Fasting serum total cholesterol, total triglycerides, LDL cholesterol, HDL cholesterol, apolipoproteins AI and B, lipoprotein (a), HbA1, plasma glucose, insulin, and C-peptide responses to a carbohydrate rich meal, body mass index (BMI), waist-hip ratio, urinary albumin excretion rate, blood pressure, smoking and family history were assessed as possible 'risk factors'. Apolipoprotein:lipid ratios were calculated to estimate lipoprotein composition. Thirty-six patients had demonstrable MVD. The presence of MVD was associated with higher total triglycerides (p < 0.05), BMI (p < 0.05), systolic blood pressure (p < 0.01), a lower apo B:non HDL cholesterol ratio (p < 0.001), and smoking (p < 0.005) but no other measures. Multiple regression analysis revealed smoking and a low apo B:non HDL cholesterol to be independently associated with MVD. The low apo B:non HDL cholesterol suggests a high cholesterol content of apo B containing lipoproteins. This lipoprotein abnormality is not a feature of NIDDM, but when present in these patients may be particularly atherogenic.

Eicosapentaenoic acid enhances myo-inositol uptake in cultured human aortic smooth muscle cells

The effects of elevated glucose and Eicosapentaenoic acid (EPA, 20:5) on myoinositol uptake in human aortic smooth muscle cells (HASMC) were evaluated. Myo-inositol incorporation into HASMC was dependent on an active transport system via Na(+)-K+ ATPase activity based on the results with Na+ deprivation and Ouabain (5 mM). Although glucose (27.5, 55 mM) inhibited 2-[3H] myo-inositol uptake, the addition of EPA (3 x 10(-4) M) prevented glucose-mediated inhibition. In addition, EPA potentiated Na(+)-K+ ATPase activity of HASMC. Since EPA decrease glucose-mediated inhibition of myo-inositol uptake, this agent might ameliorate aortic smooth muscle cell function associated with diabetes.

Dietary sugars and carbohydrate metabolism in type II diabetes

Diabetes, the most common metabolic disease, is responsible for the deaths of over 300,000 Americans annually. The incidence of the disease increases with age and since the U.S. population is graying, prevalence is also increasing. Obesity and family history are strong predictors of diabetes. The etiology of Type II diabetes is heterogeneous. The hyperglycemia of Type II diabetes can result from a variety of metabolic defects including impaired beta cell secretion, receptor deficiencies, or abnormal hepatic production or uptake of glucose. Other glucoregulatory hormones such as glucagon, growth hormone, cortisol, thyroid hormones, somatostatin, and gastric inhibitory polypeptide may contribute to the aberrations of carbohydrate metabolism. Environmental factors including stress, diet, and exercise may also contribute to the disease. Since most diabetics are obese, weight loss should be the first priority in improving status. A variety of diet and exercise regimens may help achieve this goal or even improve glucose control without weight loss. Due to the heterogeneity of the disease individualized treatment must be used to improve status of patients with the various metabolic defects of Type II diabetes.

Diabetes and atherosclerosis: an epidemiologic view

Diabetes is associated with changes in plasma lipids and lipoproteins into atherogenic direction. In IDDM these changes are small or absent if good metabolic control can be maintained. Diabetic nephropathy is, however, associated with the appearance of dyslipoproteinemia. In NIDDM plasma total and VLDL triglyceride levels are elevated, and HDL-cholesterol level is decreased, and this pattern of dyslipoproteinemia does not always respond to improved control of hyperglycemia. Abnormalities of lipoprotein metabolism, not reflected in conventional plasma lipid and lipoprotein level measurements, and glucosylation of lipoproteins and resulting alterations in lipoprotein catabolism may be of importance in the enhanced atherogenesis in diabetes. Both IDDM and NIDDM are associated with an increased frequency of hypertension, but the underlying mechanisms appear to be different. In IDDM hypertension is usually associated with the development of diabetic nephropathy and thus with a long duration of the disease. In NIDDM hypertension is often present already at the time of diagnosis, and also in IGT, the precursor stage of NIDDM, the prevalence of hypertension is already increased. Obesity explains only in part the high prevalence of hypertension in patients with NIDDM. Diabetes is known to be associated with multiple abnormalities in hemostatic factors and, although these abnormalities may contribute importantly to the increased risk of ASVD in diabetic patients, information about their real role is scanty and conflicting. The impact of general major risk factors for ASVD, elevated plasma cholesterol, elevated blood pressure, and smoking, on the risk of ASVD appears to be similar in diabetics and nondiabetics. Only a relatively small proportion of the excessive occurrence of ASVD in diabetics can, however, be explained by the effects of diabetes on the levels of general risk factors for ASVD. This proportion mediated through the effects of diabetes on risk factors is larger in female diabetics than in male diabetics. The major proportion of the excess of ASVD in diabetics remains, however, unexplained and must be due to effects of diabetes itself through mechanisms that are incompletely understood.

Non-insulin-dependent diabetes in older patients. Complications and risk factors

Non-insulin-dependent diabetes mellitus is predominantly a disease of aging, with more than 70 percent of non-insulin-dependent (type II) diabetic patients older than 55 years of age. The prevalence of macrovascular, microvascular, and neurologic complications in outpatients with type II diabetes between the ages of 55 and 74 was compared with that in a similarly aged nondiabetic group of patients. The association between duration of diabetes, hypertension, age, and other putative risk factors that are prevalent in this elderly diabetic population and the occurrence of complications was explored. This cross-sectional survey confirmed a significant increase in retinopathy, neuropathy, impotence, and macrovascular complications in patients with type II diabetes. Within the diabetic population, duration of disease was associated with the occurrence of retinopathy and neuropathy, but not associated with such macrovascular complications as coronary artery disease. Gender, type of therapy, and previously identified risk factors for vascular disease such as hypertension had little impact on the prevalence of complications in this population. The notion that type II diabetes in the elderly represents "mild" diabetes with regard to complications must be discarded. Further identification of risk factors within this diabetic population may suggest therapeutic approaches that will prevent or ameliorate the development of complications.