Con Tsalamandris

Progressive Decline in Renal Function in Diabetic Patients With and Without Albuminuria

This study describes patterns of progression of albuminuria and renal function in a subgroup of 40 patients from a total cohort of 211 diabetic patients (118 type I, 93 type II) followed over a period of 8–14 years. Forty patients (18 with type I diabetes, 22 with type II diabetes) showed progressive increases in albumin excretion rate (AER) and/or decreases in creatinine clearance (CC) during the study period. Of these, AER alone increased in 15 patients, AER increased and CC decreased in 13 patients, and CC alone decreased in 12 patients, with a similar distribution of type I and type II diabetic patients in each group. Of the 28 patients who showed an increase in albuminuria, AER increased at an annual rate of 30–40%, resulting in a 4- to 8-fold increase in AER to > 20 μg/min during the study. Of the 25 patients who showed a decrease in renal function, CC decreased at an annual rate of 4–5 ml/min, resulting in an approximate halving of CC to < 90 ml/min during the study. The rate of fall in CC was not related to the presence or absence of concomitant increases in albuminuria. However, a significant preponderance of women in the group showed a decline in CC alone. The decline in CC was associated with an increase in plasma creatinine as well as a progressive decrease in urinary creatinine excretion, but the underlying mechanisms remain unexplained. These data support the concept that a subgroup of diabetic patients may show a decline in renal function in the absence of significant increases in AER. Additional functional and structural data will be needed to determine if these patients have diabetic nephropathy. However, this study does suggest that albuminuria alone may not predict renal functional changes in all diabetic patients.

Influence of age on the presentation and outcome of acidotic and hyperosmolar diabetic emergencies

Background: Diabetic emergencies associated with ketoacidosis (DKA) and a hyperosmolar, hyperglycaemic state (HHS) are both acute life‐threatening metabolic disturbances. Traditionally, DKA and HHS have been classified as distinct entities but there is evidence to suggest that patients can present with elements of both conditions.

Effects of Insulin on Body Composition in Patients with Insulin-dependent and Non-insulin-dependent Diabetes

Insulin is used to control blood glucose but may have an adverse effect on the amount and distribution of fat mass and other cardiovascular risk factors. To test this hypothesis the effect of insulin therapy on blood glucose, body composition, and lipid levels was measured during 6 months in 9 patients with newly diagnosed insulin‐dependent (Type 1) diabetes mellitus (IDDM) and 15 patients with non‐insulin dependent (Type 2) diabetes (NIDDM) and secondary failure of therapy with oral hypoglycaemic agents. Both groups received similar daily doses of insulin (∼0.6 units kg−1 day−1). Glycaemic control improved during 6 months treatment in both groups, although the reduction in HbA1c was greater in IDDM (5.2 ± 0.7 %) than in NIDDM (2.0 ± 0.4 %, p < 0.001). All parameters of the lipid profile improved in IDDM but not in NIDDM. Body weight, lean mass, and fat mass, measured by dual energy x‐ray absorptiometry, increased at 1 month in IDDM but not in NIDDM. By 6 months, body weight had increased more in IDDM than NIDDM (9.1 ± 1.2 vs 3.77 ± 0.5 kg, p < 0.01). The increase in weight was predominantly lean mass in IDDM (60.4 ± 9.3 %) and fat mass in NIDDM (59.9 ± 8.4 %). The increase in lean mass was greater in IDDM than NIDDM (5.6 ± 1.1 vs 1.4 ± 0.3 kg, p < 0.001). Fat mass increased by similar increments in IDDM and NIDDM (3.4 ± 0.8 vs 2.4 ± 0.5 kg, p = ns) and was predominantly an increase in trunk fat (IDDM: 2.3 ± 0.6 kg, NIDDM: 2.0 ± 0.4 kg, p = ns). The central/peripheral fat mass ratio prior to treatment was lower in IDDM than NIDDM (0.64 ± 0.05 vs 1.09 ± 0.09, p < 0.01) and then increased in IDDM by 0.32 ± 0.15 (p = 0.07) and in NIDDM by 0.22 ± 0.06 (p < 0.001). In conclusion, insulin therapy is associated with weight gain in both IDDM and NIDDM. In the former, weight gain reflects increases in lean mass whereas in NIDDM it reflects an increase in trunk fat mass. It remains to be determined whether this trend to central obesity partly offsets other benefits of insulin therapy in NIDDM.

Elevated iron indices in patients with diabetes.

Aims  Excess iron has been implicated in the pathogenesis of diabetes and its complications. This study documents the assessment of plasma iron indices and the correlation between transferrin saturation with biochemical and clinical parameters in a cross‐sectional survey of 820 patients with diabetes in long‐term follow‐up in a single clinic.

Anaemia in Diabetes: An Emerging Complication of Microvascular Disease

Diabetes as the dominant cause of ESRD is also the major cause of renal anaemia. However, most patients with diabetic kidney disease will succumb to co-morbid vascular disease or heart failure before developing severe renal impairment. In these patients, anaemia is also common finding, with a 2-3 times greater prevalence and earlier onset than in patients with renal impairment from other causes. We have recently shown that at least one in five outpatients with type 1 or type 2 diabetes in tertiary referral clinics have anaemia, in whom it constitutes a significant additional burden. Impaired renal erythropoietin release in response to declining haemoglobin levels appears to be the major contributor to anaemia in diabetes. This may be due to the predominance of damage to cells and vascular architecture of the renal tubulointerstitium associated with diabetic nephropathy that may be apparent, like albuminuria, before demonstrable changes in renal function. In addition, systemic inflammation, autonomic neuropathy and reduce red cell survival may also compound anaemia in diabetes. While anaemia may be considered a marker of diabetic kidney disease, reduced haemoglobin levels, even within the normal range, identify diabetic patients with an increased risk of hospitalisation and mortality. Anaemia may also be significant in determining the outcome of heart failure and hypoxia-induced organ damage in patients with diabetes. Upcoming studies will determine whether correction of anaemia in diabetes will lead to improved outcomes in these patients.

The accuracy of cystatin C and commonly used creatinine-based methods for detecting moderate and mild chronic kidney disease in diabetes

Background  The accuracy of measuring serum cystatin C levels for detecting various stages of chronic kidney disease (CKD) in diabetes is still unclear.

Present and future of osteoporosis therapy

In the 50-year “modern” history of osteoporosis, there have been about 17 antifracture studies with sufficient attention to design to allow inference regarding efficacy. Antivertebral fracture efficacy has been reported with etidronate, estrogen patch, calcitonin, and 1,25-dihydroxyvitamin D. Two studies using fluoride were positive, and two were negative. Hip fractures have been neglected. One study showed efficacy of hip protectors, one showed efficacy of vitamin D and calcium in nursing home dwellers. The source of most hip fractures is the community. One community based antihip fracture efficacy study using annual injections of vitamin D was positive. There have been no antivertebral or antihip fracture studies in men, or in corticosteroid-related osteoporosis in men or women. Lack of independently repeated demonstration of efficacy, small fracture numbers, and data pooling in some of these (the best) studies leave great uncertainty. Estrogen and bisphosphonates appear to be the best options at this time. New data suggest that calcium supplementation is likely to reduce the rate of bone loss and perhaps reduce fracture rates. The challenge is to maintain and restore the constituents of bone mineral density (BMD), that is: to promote periosteal and endosteal bone formation; reduce endosteal bone resorption and cortical porosity; and increase trabecular thickness, number, and connectivity. There are many opportunities, for instance, intermittent parathyroid hormone (PTH) increases bone strength and, with estrogen, may increase connectivity. The anabolic effects of PTH may be partly mediated by IGF-1. IGF-1 increases periosteal, endosteal, and trabecular bone formation, cortical and trabecular width, and trabecular and endocortical connectivity. With bisphosphonate, IGF-1 may increase bone area and strength as the bisphosphonate decreases medullary area while IGF-1 increases subperiosteal area. Anabolic effects of fluoride warrant further study provided that the study design addresses the issue of bone strength, the narrow toxic-therapeutic window, and cortical bone loss. Aluminum, a constituent of zeolite, has anabolic effects which may be partly mediated by TGF-β. Prostaglandin E2 increases periosteal and endosteal bone formation but may increase cortical porosity. More data are needed regarding these growth factors, silicon compounds, strontium salts, and flavenoids. The effects of medroxyprogesterone and 19 norprogestins on BMD have not been compared. Raloxifene, a new estrogen agonist free of endometrial hyperplastic effects, is being studied. Most treated individuals with osteoporosis (i.e., low BMD with or without a fracture) will not suffer a fracture so treatment must be safe. Success—absence of fracture—will be measured by the epidemiologist because it is difficult to distinguish efficacy from chance in an individual as the peak incidence of fractures in the community is usually only about 1–4/100 per year.

Functional erythropoietin deficiency in patients with Type 2 diabetes and anaemia

Aims  Anaemia is a common finding in patients with diabetic nephropathy. Impaired production of erythropoietin is thought to be the predominant cause, as a result of renal microvascular disease. This study aims to determine the prevalence of functional erythropoietin deficiency in a cross‐sectional survey of patients with Type 2 diabetes.

Bone Loss at the Proximal Femur and Reduced Lean Mass Following Liver Transplantation: A Longitudinal Study

The longevity of recipients of liver transplant may be compromised by spinal osteoporosis and vertebral fractures. However, femoral neck fractures are associated with a higher morbidity and mortality than spine fractures. As there is little information on bone loss at this clinically important site of fracture, the aim of this study was to determine whether accelerated bone loss occurs at the proximal femur following transplantation. Bone mineral density and body composition were measured at the femoral neck, lumbar spine and total body, using dual x-ray absorptiometry in 22 men and 19 women, age 46 +/- 1.4 y (mean +/- SEM) before and at a mean of 19 mo after surgery (range 3-44). Results were expressed in absolute terms (g/cm2) and as a z score. Before transplantation, z scores for bone mineral density were reduced at the femoral neck (-0.47 +/- 0.21 SD), trochanter (-0.56 +/- 0.19 SD), Wards triangle (-0.35 +/- 0.14 SD), lumbar spine (-0.76 +/- 0.13 SD), and total body (-0.78 +/- 0.15 SD) (all P < 0.01 to < 0.001). Following transplantation, bone mineral density decreased by 8.0 +/- 1.7% at the femoral neck (P < or = 0.01) and by 2.0 +/- 1.2% at the lumbar spine (P < or = 0.05). Total weight increased by 12.2 +/- 2.3%, lean mass decreased by 5.7 +/- 1.4%, while fat mass increased from 24.1 +/- 2.0% to 35.1 +/- 1.8% (all P < or = 0.001). Patients with end-stage liver disease have reduced bone mineral density. Liver transplantation is associated with a rapid decrease in bone mineral density at the proximal femur, further increasing fracture risk and a reduction in lean (muscle) mass, which may also predispose to falls. Prophylactic therapy to prevent further bone loss should be considered in patients after liver transplantation.

Relationship of progressively increasing albuminuria to apoprotein(a) and blood pressure in Type 2 (non-insulin-dependent) and Type 1 (insulin-dependent) diabetic patients

SummaryThis study has explored the temporal relationship between apoprotein(a), blood pressure and albuminuria over a mean interval of 11 years in a cohort of 107 diabetic patients of whom 26 (14 Type 2 (non-insulin-dependent), 12 Type 1 (insulin-dependent) had progressively increasing albuminuria (‘progressors’). In Type 2 diabetic patients, no significant differences were noted for HbA1, blood pressure, creatinine clearance or serum lipids between progressors and non-progressors. In Type 1 diabetic patients, final systolic and diastolic blood pressures were higher in progressors compared with non-progressors and progressors showed impairment of renal function in association with a rise in blood pressure at the macroalbuminuric stage. Initial apoprotein(a) levels were similar in progressors and non-progressors of either diabetes type. Apoprotein(a) levels increased exponentially with time in 12 of 14 Type 2 progressors but only in 5 of 12 Type 1 progressors (p<0.01). In Type 2 diabetic patients, the annual increase in apoprotein(a) levels was 9.1±2.4%, which was significantly greater than in non-progressors, 2.0±1.2% (p<0.01) and also exceeded the rates of increase of apoprotein(a) in progressors with Type 1 diabetes, 4.0±1.4%, (p<0.05). Apoprotein(a) levels correlated significantly with albuminuria in 8 of 14 Type 2 progressors but only in 3 of 12 Type 1 progressors (p<0.05). The rate of increase of apoprotein(a) levels was not related to mean HbA1, creatinine or creatinine clearance levels, or to albuminuria. The rate of rise of apoprotein(a) was not influenced by initial apoprotein(a) levels, suggesting that specific apoprotein(a) isoforms do not influence albuminuria-related increases in apoprotein(a). The data are consistent with the hypothesis that apoprotein(a) levels increase in response to albuminuria and may be part of a self-perpetuating process. This study also suggests that increases in apoprotein(a) levels commence during the microalbuminuria stage in diabetic patients, which is earlier than has been documented in non-diabetic proteinuria.