Clinical impact of the leptin to soluble leptin receptor ratio on subclinical carotid atherosclerosis in patients with type 2 diabetes

AIM

The adipocyte-derived hormone leptin plays a key role in the regulation of food intake and energy expenditure. Recent studies have suggested that leptin is also involved in the pathogenesis of obesity-associated atherosclerosis and cardiovascular disease. In this study, we investigated the associations of leptin and the soluble leptin receptor (sOb-R) with atherosclerosis in patients with type 2 diabetes.

METHODS

Three hundred seventeen type 2 diabetic subjects were enrolled in this cross-sectional study. Fasting plasma leptin and sOb-R concentrations were measured by enzyme-linked immunosorbent assays. The intima-media thickness (IMT) of the common carotid artery was measured by ultrasound.

RESULTS

The IMT was significantly associated with sOb-R concentrations, age, diabetes duration, serum creatinine (sCre) levels, and systolic blood pressure (SBP), but not with leptin concentrations or the leptin/sOb-R ratio. The concentrations of leptin (r=0.478, p<0.001) and the sOb-R (r= -0.404, p<0.001) and the leptin/sOb-R ratio (r=0.501, p<0.001) were strongly correlated with IMT in subjects treated with insulin for glycemic control, but not in those treated with diet alone or oral hypoglycemic agents. Multiple regression analysis, including age, sex, diabetes duration, body mass index, SBP, HbA1c, triglycerides, LDL-cholesterol, sCre, smoking, and insulin therapy, revealed that plasma leptin and the leptin/sOb-R ratio were independently associated with IMT in subjects treated with insulin.

CONCLUSIONS

Plasma leptin and the leptin/sOb-R ratio are associated with atherosclerosis in patients with type 2 diabetes on insulin therapy, and these associations were independent of obesity and other cardiovascular risk factors.

Randomized Teriparatide [human parathyroid hormone (PTH) 1-34] Once-Weekly Efficacy Research (TOWER) trial for examining the reduction in new vertebral fractures in subjects with primary osteoporosis and high fracture risk

CONTEXT

Weekly teriparatide injection at a dose of 56.5 μg has been shown to increase bone mineral density.

OBJECTIVE

A phase 3 study was conducted to determine the efficacy of once-weekly teriparatide injection for reducing the incidence of vertebral fractures in patients with osteoporosis.

DESIGN AND SETTING

In this randomized, multicenter, double-blind, placebo-controlled trial conducted in Japan, the incidence of morphological vertebral fractures by radiographs was assessed.

PATIENTS

Subjects were 578 Japanese patients between the ages of 65 and 95 yr who had prevalent vertebral fracture.

INTERVENTION

Subjects were randomly assigned to receive once-weekly s.c. injections of teriparatide (56.5 μg) or placebo for 72 wk.

MAIN OUTCOME MEASURE

The primary endpoint was the incidence of new vertebral fracture.

RESULTS

Once-weekly injections of teriparatide reduced the risk of new vertebral fracture with a cumulative incidence of 3.1% in the teriparatide group, compared with 14.5% in the placebo group (P < 0.01), and a relative risk of 0.20 (95% confidence interval, 0.09 to 0.45). At 72 wk, teriparatide administration increased bone mineral density by 6.4, 3.0, and 2.3% at the lumbar spine, the total hip, and the femoral neck, respectively, compared with the placebo (P < 0.01). Adverse events (AE) and the dropout rates by AE were more frequently experienced in the teriparatide group, but AE were generally mild and tolerable.

CONCLUSION

Weekly s.c. administration of teriparatide at a dose of 56.5 μg may provide another option of anabolic treatments in patients with osteoporosis at higher fracture risk.

Decreased serum adrenal androgen dehydroepiandrosterone sulfate and mortality in hemodialysis patients

BACKGROUND

Endocrine and metabolic abnormalities may affect the survival of hemodialysis patients. Serum dehydroepiandrosterone sulfate (DHEA-S), an adrenal androgen with anabolic properties, is known to be lowered in ill patients and predicts poor outcome in the general population and in those with cardiac disease. The aims of this study were to examine a possible change in the DHEA-S level in dialysis patients and its association with survival in this population.

METHODS

This was an observational cohort study in 494 prevalent hemodialysis patients (313 men and 181 women) in urban area of Osaka, Japan. The main exposure was the baseline DHEA-S level in December 2004 and the key outcome was all-cause mortality during the subsequent 5 years. Also, DHEA-S levels were compared between the hemodialysis patients and 122 matched healthy controls.

RESULTS

The median (inter-quartile range) DHEA-S levels were 771 (447-1351) and 414 (280-659) ng/mL for male and female dialysis patients, respectively, and these values were significantly lower by 40-53% than the healthy control levels. Among the hemodialysis patients, DHEA-S was lower in women, those with older age, pre-existing cardiovascular disease, lower serum albumin and higher C-reactive protein. During the follow-up, we recorded 101 deaths. A low DHEA-S level was a significant predictor of all-cause mortality independent of potential confounders in male, but not in female, hemodialysis patients.

CONCLUSIONS

The serum DHEA-S level is decreased in hemodialysis patients and associated with mortality in men. These results support the growing observational evidence that uremia-induced endocrine alterations including decreased sex hormones may be linked to adverse clinical outcomes.

Serum adiponectin and bone mineral density in male hemodialysis patients

SUMMARY

Bone mineral density of the 1/3 distal radius, ultra-distal radius, and lumbar spine correlated significantly and negatively with serum adiponectin. There was a significant positive correlation between serum adiponectin and serum NTX. Thus, adiponectin may play a role in mineral and bone disorder in chronic kidney disease stage 5 dialysis (CKD 5D) patients.

INTRODUCTION

Serum adiponectin, an adipocyte-produced hormone, has been reported to correlate negatively with bone mineral density (BMD) in the general population. However, little is known about the association between adiponectin and BMD in patients with CKD.

METHODS

BMD of the 1/3 distal and ultra-distal radius, which are enriched with cortical and cancellous bone, respectively, and the lumbar spine was measured by dual X-ray absorptiometry in 114 Japanese male hemodialysis patients (age 61.0 ± 11.1 years; hemodialysis duration 6.6 ± 3.0 years; 43.9% diabetics). Serum total adiponectin, bone formation marker (bone alkaline phosphatase, BAP), and bone resorption marker (cross-linked N-telopeptide of type I collagen (NTX)) were measured.

RESULTS

The BMD of the 1/3 distal radius, ultra-distal radius, and lumbar spine correlated significantly and negatively with serum adiponectin level (r = -0.229, p = 0.014; r = -0.286, p = 0.002; r = -0.227, p = 0.013, respectively). In multiple linear regression analyses, serum adiponectin was significantly and independently associated with the BMD of the 1/3 distal radius (R(2) = 0.173, p < 0.001) and ultra-distal radius (R(2) = 0.278, p < 0.001) after adjustment of age, hemodialysis duration, body weight, %fat mass, and log [intact PTH], although it was not with the BMD of the lumbar spine. There was a significant positive correlation between serum adiponectin and serum NTX (r = 0.321, p < 0.001), although there was no significant correlation between serum adiponectin and serum BAP.

CONCLUSION

Increased levels of serum adiponectin were associated with decrease in BMD in male hemodialysis patients. Adiponectin may play a role in mineral and bone disorder, possibly in bone resorption, of patients with CKD 5D.

Antialbuminuric advantage of cilnidipine compared with L-type calcium channel blockers in type 2 diabetic patients with normoalbuminuria and microalbuminuria

We evaluated the antialbuminuric advantage of cilnidipine, an N/L-type calcium channel blocker (CCB), compared with L-type CCBs in diabetic patients with normoalbuminuria and microalbuminuria. The study was a multicenter, non-randomized crossover trial. Participants were 90 type 2 diabetic patients exhibiting either normo- or microalbuminuria, and undergoing CCB treatment for ≥6 months prior to study entry. The CCB at the time of entry was continued for the first 6 months (Period 1). Treatment was subsequently switched from cilnidipine to an L-type CCB, or vice versa, for the second 6-month observation period (Period 2). During Period 1, the L-type CCB group showed a significant increase of urinary albumin excretion (UAE) over time, while the cilnidipine group showed no significant elevation. During Period 2, switching of the treatment from the L-type CCB to cilnidipine resulted in significant reduction of the UAE, whereas switching from cilnidipine to the L-type CCB resulted in no significant change in the UAE. This study demonstrated that the antialbuminuric effect of Cilnidipine, but not the L-type CCBs, was sustained even in patients treated for a long time. In addition, the antialbuminuric effect can be anticipated after switching from an L-type CCB to cilnidipine, but not vice versa.

Efficacy and safety of monthly oral minodronate in patients with involutional osteoporosis

Monthly minodronate at 30 or 50 mg had similar efficacy as 1 mg daily in terms of change in bone mineral density (BMD) and bone turnover markers with similar safety profiles. This new regimen provides patients with a new option for taking minodronate.

INTRODUCTION

Minodronate at a daily oral dose of 1 mg has been proven to have antivertebral fracture efficacy. In the present study, the efficacy and safety of oral minodronate at monthly doses of either 30 mg or 50 mg were compared with a daily dose of 1 mg.

METHODS

A total of 692 patients with involutional osteoporosis were randomized to receive minodronate at either 30 or 50 mg monthly or a daily dose of 1 mg. The primary endpoint was the percent change from baseline in lumbar spine (LS) BMD at 12 months. Total hip BMD, bone turnover markers, serum calcium (Ca), and parathyroid hormone (PTH) levels were also evaluated.

RESULTS

Minodronate at monthly doses of 30 or 50 mg were noninferior to the 1 mg daily dose in terms of change in LS-BMD. Changes in total hip BMD were also comparable. Although a transient decrease in serum Ca and increase in PTH levels were observed in all three groups at slightly different magnitudes and time courses, changes in bone turnover markers were comparable among the different dosage groups with a similar time course. Safety profiles were also comparable.

CONCLUSION

Minodronate at monthly doses of 30 or 50 mg has similar efficacy to the daily 1 mg dose in terms of BMD and bone turnover markers with similar tolerability.

Thrice-weekly insulin injection with nurse's support for diabetic hemodialysis patients having difficulty with self injection

Although poor glycemic control is known as an independent predictor of mortality in diabetic hemodialysis patients, it is often difficult for some patients to perform standard self injection insulin therapy. Some practical methods are needed for such patients. We evaluated the usefulness of a new regimen of insulin therapy, namely thrice-weekly insulin injection with nurse's support (TWINS) using insulin NPH or glargine at the end of each hemodialysis sessions in 5 outpatients on hemodialysis with type 2 diabetes mellitus showing HbAlc levels > or = 8.0% (JDS). HbA1c levels were successfully decreased in all patients from 9.3 +/- 1.1% to 6.9 +/- 0.7% (mean +/- SD) in six months without hypoglycemia symptoms. These preliminary results suggest that this regimen can be one of the practical choices in poor-controlled diabetes patients on regular hemodialysis who have difficulty in self injection of insulin.

Enhancement of cell-based therapeutic angiogenesis using a novel type of injectable scaffolds of hydroxyapatite-polymer nanocomposite microspheres

BACKGROUND

Clinical trials demonstrate the effectiveness of cell-based therapeutic angiogenesis in patients with severe ischemic diseases; however, their success remains limited. Maintaining transplanted cells in place are expected to augment the cell-based therapeutic angiogenesis. We have reported that nano-hydroxyapatite (HAp) coating on medical devices shows marked cell adhesiveness. Using this nanotechnology, HAp-coated poly(l-lactic acid) (PLLA) microspheres, named nano-scaffold (NS), were generated as a non-biological, biodegradable and injectable cell scaffold. We investigate the effectiveness of NS on cell-based therapeutic angiogenesis.

METHODS AND RESULTS

Bone marrow mononuclear cells (BMNC) and NS or control PLLA microspheres (LA) were intramuscularly co-implanted into mice ischemic hindlimbs. When BMNC derived from enhanced green fluorescent protein (EGFP)-transgenic mice were injected into ischemic muscle, the muscle GFP level in NS+BMNC group was approximate fivefold higher than that in BMNC or LA+BMNC groups seven days after operation. Kaplan-Meier analysis demonstrated that NS+BMNC markedly prevented hindlimb necrosis (P<0.05 vs. BMNC or LA+BMNC). NS+BMNC revealed much higher induction of angiogenesis in ischemic tissues and collateral blood flow confirmed by three-dimensional computed tomography angiography than those of BMNC or LA+BMNC groups. NS-enhanced therapeutic angiogenesis and arteriogenesis showed good correlations with increased intramuscular levels of vascular endothelial growth factor and fibroblast growth factor-2. NS co-implantation also prevented apoptotic cell death of transplanted cells, resulting in prolonged cell retention.

CONCLUSION

A novel and feasible injectable cell scaffold potentiates cell-based therapeutic angiogenesis, which could be extremely useful for the treatment of severe ischemic disorders.

Elemental concentrations in scalp hair, nutritional status and health-related quality of life in hemodialysis patients

Elemental concentrations in hair from hemodialysis (HD) patients have not been well investigated. We examined the relationships between the elemental concentrations in scalp hair and health-related quality of life (HRQOL) and nutritional status in HD patients. Twenty six elemental concentrations were measured in scalp hair samples from 60 male HD patients using inductively-coupled plasma mass spectrometry. To evaluate HRQOL, the Short Form 36 item health survey (SF36) was used. As indices of nutritional status, body mass index, serum parameters, and geriatric nutritional risk index (GNRI) were used. Phosphorus correlated positively with serum creatinine, blood urea nitrogen (BUN), GNRI and the physical domains of the SF36. Zinc correlated positively with serum creatinine, BUN and the physical domains of the SF36. Mercury and arsenic correlated positively with BUN. Cadmium correlated negatively with serum albumin, BUN and GNRI. Copper correlated positively with the physical domains of the SF36. Iodine correlated negatively with the physical domains of the SF36. Selenium correlated negatively with the mental domains of the SF36. In conclusion, phosphorus and zinc concentrations in scalp hair can be additional biomarkers of HRQOL and/or nutritional status in HD patients. Cadmium accumulation correlated with malnutrition. Iodine and selenium accumulation may adversely affect HRQOL. Further investigation is necessary to determine precisely how these elements affect these measures.

Relationship between fat mass and serum high-sensitivity C-reactive protein levels in prevalent hemodialysis patients

BACKGROUND/AIMS

Little is known about the relationship between fat mass distribution and chronic inflammation in dialysis patients, in whom chronic inflammation is related to morbidity and mortality.

METHODS

The fat and lean masses (truncal and nontruncal) of 452 hemodialysis patients (age: 64 ± 11 years; hemodialysis duration: 89 ± 77 months; 37% diabetics) were measured by dual X-ray absorptiometry and their association with high-sensitivity C-reactive protein (hsCRP) was examined.

RESULTS

The fat mass of the high hsCRP group (n = 106) was significantly higher than that of the normal hsCRP group (n = 346; p < 0.05); there were no significant differences in lean mass between the two groups. Truncal fat mass of the former group was significantly greater than that of the latter (p < 0.05), but there was no significant difference in nontruncal fat mass between the two groups. In multiple regression analysis, truncal fat mass (β = 0.227, p < 0.01) was significantly and independently associated with serum hsCRP levels after adjustment for age, gender and serum albumin (R(2) = 0.137, p < 0.01), whereas nontruncal fat mass was not.

CONCLUSION

Fat mass, particularly truncal fat mass, but not lean body mass, was significantly associated with serum hsCRP levels. The results suggest that truncal fat mass exhibits a distinct effect on chronic inflammation in hemodialysis patients.

P1-16-01: A Randomized, Double-Blinded, Controlled Study of Exemestane vs. Anastrozole for the First-Line Treatment of Postmenopausal Japanese Women with Hormone Receptor Positive Advanced Breast Cancer

Background The steroidal irreversible aromatase inhibitor (AI) exemestane (E), the non-steroidal reversible AI anastrozole (A) and tamoxifen (T) are approved for the first-line treatment of the postmenopausal women with hormone receptor (HR) positive advanced breast cancer (ABC) in Japan. Although there are some studies which compare the efficacy and safety of AIs and T in the first-line disease setting, the number of studies that compare efficacy and safety of AIs is limited. We conducted this multicenter, randomized, double-blinded non-inferiority study, to evaluate the time to progression (TTP) in HR positive ABC randomized to therapy with E or A.

Methods Patients (pts) who were ≥20 years [yrs], postmenopausal, ECOG PS ≤1 and had HR positive ABC that recurred after the adjuvant therapy or metastatic disease settings were eligible and randomized (1:1) to 25 mg/day of E or to 1 mg/day of A. Data were evaluated for non-inferiority of E compared to A defined as the upper limit of a two-sided 95% confidence interval (CI) of the hazard ratio (HR) of TTP being less than or equal to 1.25. The primary endpoint was TTP assessed by the independent radiological images review committee (RIRC). Secondary endpoints included TTP by investigator, time to treatment failure, overall survival (OS), objective response rate (ORR), clinical benefit rate, and safety.

Results A total of 298 pts from 58 sites were randomized to E (n=149; mean age: 63.4 yrs) or A (n=149; mean age: 64.0 yrs). The mean BMI for the E and A arms were 23.0 kg/m2 and 23.6 kg/m2, respectively. Six pts (2 pts in E arm, 4 pts in A arm) were excluded from the full analysis set due to lack of evaluation for anti-tumor response after study medication started.

Median TTP (as per RIRC) was 13.8 months (M) vs. 11.1 M for E vs. A, respectively (HR 1.007; 95% CI: 0.771−1.317). Median TTP (Investigator) was 13.8 M vs. 13.7 M for E vs. A, respectively (HR 1.059; 95% CI: 0.816−1.374). The median OS for A treated pts was 60.1 M, OS for E was not reached (as of data cut-off: December 8, 2010). ORR for E was 43.9% (95% CI: 35.3−52.8) and 39.1% (95% CI: 30.6−18.1) for A. Other analyses, including sub-population analyses are ongoing.

The incidence of treatment related adverse events (AEs) in E arm was 71.1% (n=106) and in A arm 59.7% (n=89); the AEs were mostly grade 1 and 2 in 61.7% (n=92) and 53.7% (n=80) of pts respectively. They were expected and manageable. Treatment related SAEs were similar in both groups: 6 (4.0%) in E arm and 5 (3.4%) in A arm. The most common AEs for E were hot flushes (22.1%), arthralgias (16.8%), musculoskeletal stiffness (11.4%) and γ-GTP increased (10.1%); in A arm, hot flushes (14.8%) and arthralgia (16.8%) were observed in &gt;10% pts.

Conclusions Although median TTP (RIRC) of E is slightly improved compared with that of A, the result of TTP did not meet the non-inferiority criteria. There were no significant differences found between E and A in ORR. Although AEs in E were numerically higher, the observed AE profiles were similar to those previously reported for E and A. This study shows that E is comparable to A in efficacy and safety.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P1-16-01.

Proteome analysis of laser microdissected glomeruli from formalin-fixed paraffin-embedded kidneys of autopsies of diabetic patients: nephronectin is associated with the development of diabetic glomerulosclerosis

BACKGROUND

To date, little proteomic information has been available from the glomeruli of diabetic patients, possibly due to the clinical limitations of renal biopsy in diabetic patients and insufficient quantities of such specimens for proteome analysis. The purpose of the present study was to identify altered protein expression profiles in diabetic glomeruli using formalin-fixed paraffin-embedded (FFPE) kidney tissues from diabetic patients.

METHODS

Glomeruli were laser microdissected from FFPE autopsy kidney tissues from 10 patients with diabetic nephropathy and 10 non-diabetic control patients and underwent proteome analysis using QSTAR Elite liquid chromatography with tandem mass spectrometry and iTRAQ technology. Immunohistochemical analysis was performed on 93 autopsy samples from diabetic patients with and without nephropathy (n = 45 and n = 48, respectively).

RESULTS

Thirty-one renal and urological disease-related proteins displayed a differential abundance in glomerular samples from patients with diabetic nephropathy compared with non-diabetic control patients. Among them, we found that nephronectin, which functions in the assembly of extracellular matrix, showed clearly positive immunoreactivity in diabetic glomeruli. The numerical fraction of nephronectin-positive glomerular cross sections was increased significantly in diabetic patients with nephropathy compared to those without nephropathy (32.1 ± 31.5 versus 4.14 ± 5.65%, P < 0.0001). Furthermore, there was a significant positive correlation between this numerical fraction of nephronectin-positive glomerular cross sections and the glomerular sclerosis index (ρ = 0.881, P < 0.0001, n = 93).

CONCLUSION

The present study demonstrated, for the first time, that nephronectin may be associated with the development of diabetic glomerulosclerosis and that proteome analysis with FFPE kidney tissues from diabetic patients with nephropathy is useful in understanding diabetic nephropathy.

Association of endothelial and vascular smooth muscle dysfunction with cardiovascular risk factors, vascular complications, and subclinical carotid atherosclerosis in type 2 diabetic patients

AIM

Atherosclerosis and arteriosclerosis are mainly caused by the dysfunction of arterial components, namely, vascular endothelial cells, smooth muscle cells, and the extracellular matrix. Endothelial dysfunction is well established as a predictive surrogate marker of cardiovascular events; however, little is known regarding the clinical implications of vascular smooth muscle dysfunction for cardiovascular disease and microangiopathy. In the present study, we aimed to clarify the association of arterial dysfunction with micro-/macroangiopathy and conventional cardiovascular risk factors in 181 type 2 diabetic patients (T2DM; age ± SD, 64 ± 10 years; duration of diabetes, 12 ± 10 years).

METHODS

Flow-mediated dilatation (FMD) and nitroglycerin-mediated dilatation (NMD) were assessed to evaluate endothelial dysfunction and vascular smooth muscle dysfunction, respectively, by using a novel ultrasound device, UNEXEF18G (Unex Co. Ltd., Japan).

RESULTS

The FMD and NMD were 6.4 ± 3.9% and 13.4 ± 6.6%, respectively. No significant differences in FMD were noted between T2DM with and without micro- or macroangiopathy; however, NMD in T2DM patients with micro- and macroangiopathy was significantly lower than that in T2DM patients without angiopathy. NMD decreased with the progression of chronic kidney disease (CKD) stage (p = 0.005), but not FMD (p = 0.071). On multiple regression analysis, significant independent contributors to FMD were age, smoking, systolic blood pressure, glycosylated hemoglobin, and serum total cholesterol, while those for NMD were age, systolic blood pressure, and waist circumference.

CONCLUSION

The relationship of vascular complications and cardiovascular risk factors with NMD is different from that with FMD in type 2 diabetic patients.

[Professor Morii and my academic life]

Emeritus Professor Hirotoshi Morii was an important mentor in my academic life, who was a chief editor of CLINICAL CALCIUM with Professor Yoshio Yazaki for a long time. In the study of dopamine-β-hydroxylase, hyperthyroidism was able to prove hypotonic status for sympathetic nerve system by his valuable suggestion, though this condition was believed to be hypersympathetic till 1974 when my paper was published in Journal of Clinical Endocrinology and Metabolism. His suggestion struck me at that time. And this experience continues to give me an active power through my academic life.

Trace elements in the hair of hemodialysis patients

Trace element disturbance is often observed in hemodialysis patients. While trace element concentrations have been reported in blood samples from hemodialysis patients, they have not been well investigated in scalp hair. In the present study, 22 trace elemental concentrations were measured by inductively coupled plasma-atomic emission spectrometry in the scalp hair of 80 male hemodialysis patients and compared with those of 100 healthy male subjects. In hemodialysis patients, the concentrations of beryllium, arsenic, magnesium, chromium, manganese, iron, selenium, molybdenum, iodine, vanadium, and cobalt were significantly higher than those in healthy subjects, while lead, mercury, copper, germanium, and bromine were significantly lower than those in the former group. No significant differences were observed for lithium, aluminum, cadmium, zinc, boron, or nickel. There were significant positive correlations between the duration of hemodialysis and the magnesium and manganese concentrations. There was a significant negative correlation between cadmium concentration and the duration of hemodialysis. There were significant positive correlations between dialysis efficacy (Kt/V) and magnesium, manganese, zinc, and selenium concentrations. In conclusion, trace element concentrations of the scalp hair are different between hemodialysis patients and healthy subjects. Essential trace elements, such as magnesium, manganese, zinc, and selenium, may be affected by the duration of hemodialysis and Kt/V.

Active vitamin D and acute respiratory infections in dialysis patients

BACKGROUND AND OBJECTIVES

Vitamin D has gained attention for its pleiotropic effects in areas other than bone metabolism, and the effects of vitamin D in preventing respiratory infections have been reported as one of its immunomodulating properties. This study assessed the preventive effect of vitamin D receptor activator (VDRA) on respiratory infections in dialysis patients.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Maintained Japanese hemodialysis patients (n = 508) were observed for 5 years, and the incidence of hospitalization during this period because of acute respiratory infection (ARI) was recorded.

RESULTS

Of the 508 patients, 212 had taken oral VDRA at the start of the study, whereas 296 patients had not received it. During the 5-year follow-up period, 57 patients were hospitalized because of ARIs. Kaplan-Meier analysis revealed that the incidence of hospitalization because of respiratory infection was significantly lower in patients who had been treated with VDRA compared with patients who had not (log rank test; P = 0.02). The multivariate Cox proportional hazards model demonstrated that the patients who had taken oral VDRA were at a significantly lower risk of hospitalization because of respiratory disease (hazard ratio 0.47, 95% confidence interval 0.25 to 0.90).

CONCLUSIONS

The findings of this study suggest that the administration of oral VDRA has a preventive effect on the incidence of ARIs in dialysis patients.

Advanced glycation end products, carotid atherosclerosis, and circulating endothelial progenitor cells in patients with end-stage renal disease

Numbers of endothelial progenitor cells (EPCs) have been shown to be decreased in subjects with end-stage renal disease (ESRD), the mechanism of which remained poorly understood. In this study, mutual association among circulating EPC levels, carotid atherosclerosis, serum pentosidine, and skin autofluorescence, a recently established noninvasive measure of advanced glycation end products accumulation, was examined in 212 ESRD subjects undergoing hemodialysis. Numbers of circulating EPCs were measured as CD34+ CD133+ CD45(low) VEGFR2+ cells and progenitor cells as CD34+ CD133+ CD45(low) fraction by flow cytometry. Skin autofluorescence was assessed by the autofluorescence reader; and serum pentosidine, by enzyme-linked immunosorbent assay. Carotid atherosclerosis was determined as intimal-medial thickness (IMT) measured by ultrasound. Circulating EPCs were significantly and inversely correlated with skin autofluorescence in ESRD subjects (R = -0.216, P = .002), but not with serum pentosidine (R = -0.079, P = .25). Circulating EPCs tended to be inversely associated with IMT (R = -0.125, P = .069). Intimal-medial thickness was also tended to be correlated positively with skin autofluorescence (R = 0.133, P = .054) and significantly with serum pentosidine (R = 0.159, P = .019). Stepwise multiple regression analyses reveal that skin autofluorescence, but not serum pentosidine and IMT, was independently associated with low circulating EPCs. Of note, skin autofluorescence was also inversely and independently associated with circulating progenitor cells. Thus, tissue accumulated, but not circulating, advanced glycation end products may be a determinant of a decrease in circulating EPCs in ESRD subjects.

Association of serum TRAIL levels with atherosclerosis in patients with type 2 diabetes mellitus

Tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) was originally isolated as an inducer of apoptosis. Recent cross-sectional and prospective studies suggest an inverse association of serum TRAIL levels with the severity of coronary artery disease (CAD) and with an adverse outcome in patients with CAD or heart failure. However, it is unknown whether TRAIL can inversely reflect the progression of atherosclerosis from its early stage. We therefore examined the association between TRAIL measured by ELISA and intima-media thickness (IMT) in carotid and femoral arteries evaluated by ultrasonography as a surrogate marker of atherosclerosis in 416 type 2 diabetic patients without any symptoms of CAD and heart failure. Concurrently, the existence of calcified plaque (CP) was examined. There was no significant association between TRAIL and carotid IMT (ρ=-0.096, p=0.052) or femoral IMT (ρ=-0.025, p=0.610), although TRAIL was associated with carotid IMT in a subset of patients with macrovascular diseases (ρ=-0.174, p=0.034). No difference in TRAIL levels was found between two groups with or without CP. TRAIL may not be a good candidate as a biomarker to evaluate early-stage atherosclerotic lesions.

Reduction of whole PTH/intact PTH ratio as a predictor of bone metabolism in cinacalcet treatment of hemodialysis patients with secondary hyperparathyroidism

In cinacalcet treatment of hemodialysis (HD) patients with secondary hyperparathyroidism (SHPT), not only intact parathyroid hormone (I-PTH), whole PTH (W-PTH), and bone markers, but also W-PTH/I-PTH ratio as proportion of active PTH(1-84) molecules were decreased. Changes in W-PTH/I-PTH ratio significantly correlated and predicted changes in bone marker.

INTRODUCTION

Cinacalcet partly suppresses the secretion of PTH by enhancing PTH(1-84) degradation into N-truncated fragments. The objectives of this study is to investigate the significance of the N-truncated PTH/PTH(1-84) ratio for the prediction of the effect of cinacalcet in HD patients.

METHODS

Serum parameters were measured during 12 weeks of oral cinacalcet administration at 25 mg daily in 39 HD patients with SHPT.

RESULTS

Serum Ca, Pi, W-PTH, I-PTH, and W-PTH/I-PTH ratio all decreased significantly in a time-dependent manner during cinacalcet administration. Serum tartrate-resistant acid phosphatase (TRAP) 5b reflected these changes more precisely than serum N-telopeptide of type-I collagen. At 1 week, changes in I-PTH and W-PTH correlated significantly with those in serum Pi, but not Ca. Changes in serum Pi (but not Ca) and serum W-PTH also correlated significantly with changes in serum TRAP5b at both 4 and 12 weeks, while changes in serum I-PTH correlated significantly with those in serum TRAP5b only at 12 weeks. Changes in the serum W-PTH/I-PTH ratio correlated significantly with those in serum TRAP5b at both 4 and 12 weeks, and changes in serum W-PTH/I-PTH ratio at 4 weeks showed a tendency for a correlation with changes in serum TRAP5b at 12 weeks. HD patients with a reduced W-PTH/I-PTH ratio after 4 weeks had a significantly greater reduction of TRAP5b over 12 weeks.

CONCLUSION

W-PTH and the W-PTH/I-PTH ratio allow estimation of the potency of cinacalcet in enhancement of PTH degradation, and thus no less reliable markers than I-PTH for reflecting cinacalcet-induced bone resorption.

Different impacts of neck circumference and visceral obesity on the severity of obstructive sleep apnea syndrome

Our aim was to investigate the significance of neck circumference (NC) on the presence and severity of obstructive sleep apnea (OSA) syndrome independent of visceral fat (VF) obesity. A total of 219 subjects with suspected OSA underwent a complete polysomnography (PSG) study, along with the measurement of NC, and total body fat (TF) and VF levels (VFLs) measured by bioelectrical impedance analysis. We proposed NC divided by height (NC/H) as the simple index for height-corrected NC in Japanese subjects. NC/H exhibited a significantly stronger correlation than NC per se with BMI (r = 0.781 vs. 0.675, P = 0.0178), TF (r = 0.531 vs. 0.156, P < 0.0001), and VF (r = 0.819 vs. 0.731, P = 0.0203), indicating that NC/H is a better indicator of visceral obesity than NC per se. Interestingly, despite the strong correlation between NC/H and VFL, VFL was significantly associated with the apnea-hypopnea index (AHI) ≥ 5, ≥ 15, and ≥ 30, but not with ≥ 40 or ≥ 50, whereas NC/H was significantly associated with higher AHI values, i.e., AHI ≥ 50 but not with lower AHI value. Furthermore, multiple regression analyses revealed that VFL and NC/H were independently associated with the square root of AHI (AHI(0.5)) levels in obese and nonobese patients, respectively. In conclusion, NC is associated with the severity of OSA independently of visceral obesity, especially in nonobese patients.

Design of a pragmatic approach to evaluate the effectiveness of concurrent treatment for the prevention of osteoporotic fractures: rationale, aims and organization of a Japanese Osteoporosis Intervention Trial (JOINT) initiated by the Research Group of Adequate Treatment of Osteoporosis (A-TOP)

The aim of osteoporosis treatment is to prevent future fractures. Although concurrent treatment has been used very frequently for osteoporosis in clinical practice, there are no data on accurate and verified effectiveness of concurrent treatment for fracture prevention in patients with osteoporosis. To clarify the clinical usefulness of concurrent treatment, the Japan Osteoporosis Society has authorized the establishment of the A-TOP (Adequate Treatment of Osteoporosis) research group. The objective of this research is to establish a design for a clinical trial to prove whether concurrent treatment using both alfacalcidol (1-alpha-hydroxycholecalciferol) and alendronate is more effective as compared to treatment using alendronate alone in terms of fracture prevention. The present study was named JOINT (Japanese Osteoporosis Intervention Trial) and is based on a method using national, prospective, randomized, open-labeled, blinded endpoints focusing on postmenopausal osteoporosis with a high risk for fracture. The patients were mainly selected by practitioners and allocated randomly by a central registration system into two groups, of which one received 5 mg/day of alendronate alone, and the other received 1 μg/day of 1-alpha-hydroxycholecalciferol (alfacalcidol) in addition to the alendronate. The endpoints focused primarily on fracture prevention, and the patients' quality of life (QOL) and change in body height, as well as adherence and the adverse events of the treatments were evaluated secondarily. To obtain sufficient statistical power in the events during a 2-year observation period, the patients who are expected to have higher risk were selected to participate in this study, and it was decided that the final plan would involve 890 patients per group (two-sided alpha = 0.05, power = 0.8). Data collection began in November 2003. Correspondence regarding the registration of the investigator and the progress of the study was conducted through a web system from the Public Health Research Foundation to practitioners.

Receptor for advanced glycation end-products (RAGE) regulation of adiposity and adiponectin is associated with atherogenesis in apoE-deficient mouse

OBJECTIVE

Receptor for advanced glycation end-products (RAGE) has been shown to be involved in cardiovascular diseases. We examined the involvement of RAGE in atherosclerosis under non-diabetic status, and its relation to the effect on adiposity.

METHODS

Apolipoprotein E (apoE)(-/-)RAGE(+/+) or apoE(-/-)RAGE(-/-) mice were fed with an atherogenic diet or the standard chow diet. Adiposity was determined by weight of epididymal adipose tissue, adipocyte size and serum adiponectin. Aortic atherosclerosis was morphometrically determined.

RESULTS

ApoE(-/-)RAGE(-/-) mice exhibited significantly less total aortic plaque area than apoE(-/-)RAGE(+/+) mice. Body weight, epididymal fat weight, and epididymal adipocyte size were also significantly less in apoE(-/-)RAGE(-/-) mice than apoE(-/-)RAGE(+/+) mice. Serum adiponectin, but not tumor necrosis factor-alpha, was significantly higher in apoE(-/-)RAGE(-/-) mice than apoE(-/-)RAGE(+/+) mice. Simple regression analysis revealed that the total aortic plaque area was positively associated with epididymal fat weight, epididymal adipocyte size, and negatively with serum adiponectin levels. Multiple regression analyses revealed that RAGE genotype and serum adiponectin were mutually interrelated in determining aortic atherosclerosis. Finally, immunohistochemical and real-time RT-PCR analyses revealed that RAGE was indeed expressed in both adipocytes and endothelial cells in epididymal adipose tissue.

CONCLUSION

RAGE-mediated regulation of adiposity in non-diabetic status could be attributable to the progression of atherosclerosis.

Different effects of diabetic autonomic neuropathy on regional transcutaneous oxygen tension in patients with peripheral arterial disease

BACKGROUND

Diabetic autonomic neuropathy (DAN) is thought to reduce skin nutritive perfusion through increase of arteriovenous shunting flow, resulting in foot ulceration. However, the correlation between skin tissue oxygenation and DAN has not been fully elucidated. Transcutaneous oxygen tension (TcPO2) is a reliable indicator of skin nutritional microcirculation. The aim of this study was to evaluate the influence of DAN on skin microcirculation by using TcPO2 measurements.

METHODS

The resting TcPO2 (REST-TcPO2) and post-exercise TcPO2 (Ex-TcPO2) of the calf and dorsalis pedis regions were measured simultaneously in 52 patients (104 limbs), including 41 diabetes patients. All patients underwent angiography, and the presence of arterial stenosis was evaluated.

RESULTS

TcPO2 levels were compared among the groups of patients with no neuropathy, sensory neuropathy alone, and DAN. In both the calf and dorsalis pedis regions, Ex-TcPO2 levels in diabetes patients with DAN were significantly lower than those in diabetes patients without any neuropathy. However, there was no difference in REST-TcPO2 levels among these groups. We then performed multiple regression analysis to evaluate the influence of DAN on each TcPO2 after adjustment for multiple clinical factors. DAN was a significant determinant of REST- and Ex-TcPO2 in the calf region, and it was independent of arterial stenosis and sensory neuropathy. In contrast, DAN was not an independent determinant of REST- and Ex-TcPO2 in the dorsalis pedis region.

CONCLUSIONS

We, for the first time, showed that DAN has significant effects on skin microcirculation of the calf region but not of the dorsalis pedis region.

Increased osteocyte death and mineralization inside bone after parathyroidectomy in patients with secondary hyperparathyroidism

In order to gain insight into the mechanisms underlying the dynamic changes in bone metabolism and bone quality after parathyroidectomy (PTX) in secondary hyperparathyroid patients with high levels of parathyroid hormone (PTH), we performed bone histomorphometric analysis with tetracycline labeling in iliac bone biopsy specimens taken before and after PTX, with special attention paid to osteocytes. At 2 to 4 weeks after PTX, PTH concentrations decreased markedly with evident reductions in bone turnover markers. Histomorphometry revealed that at 2 to 4 weeks following PTX, the osteoclast surface decreased to nearly 0%, with a substantial increase in osteoid volume and a reduction in fibrosis volume. Labeling with tetracycline was observed not only at the mineralization front on the bone surface but also around the osteocyte lacunar walls and canaliculi within both the basic multicellular units (BMUs) and bone structural units (BSUs), suggesting that mineralization was taking place along the lacunocanalicular system after PTX. The tetracycline-labeled area was much greater in the BSUs than in the BMUs and at the mineralization front, and the tetracycline labeling in the BSUs was markedly increased after PTX compared with that in the low- and high-PTH control groups without PTX. The osteocyte number was decreased significantly after PTX, concomitant with an increase in the number of empty lacunae and a reduction of lacunar volume. Thus the increased osteocyte death and mineralization around the lacunocanalicular system in association with a rapid decline in PTH may underlie the changes in bone metabolism and quality that occur following PTX.

Poor muscle quality rather than reduced lean body mass is responsible for the lower serum creatinine level in hemodialysis patients with diabetes mellitus

BACKGROUND

The serum creatinine level is significantly lower in well-nourished hemodialysis patients with diabetes mellitus (DM) than in their non-DM counterparts, despite the presence of anuria in these patients. The factors associated with this finding have not been determined.

PATIENTS AND METHODS

We evaluated the association of serum creatinine with handgrip strength (HGS) and lean body mass index (LMI) in a cross-sectional study of 102 DM and 208 non-DM hemodialysis patients to determine if poorer muscle quality in DM patients could explain the reduced level of serum creatinine. All the DM patients were well-nourished. Grip dynamometry and dual-energy X-ray absorptiometry (DXA) were used to measure HGS and LMI, respectively.

RESULTS

The DM patients had a significantly lower serum creatinine level and HGS compared to the non-DM patients, but whole-body LMI and LMI of the upper limbs did not differ between the two groups of patients. The DM patients had significantly lower serum creatinine/whole-body LMI, serum creatinine/arm LMI, HGS/whole-body LMI, and HGS/arm LMI ratios. The serum creatinine level was significantly correlated with HGS and with whole-body and upper limb LMI in both groups of patients. However, regression analyses of LMI with serum creatinine and HGS gave significantly shallower slopes for the DM patients compared to the non-DM patients.

CONCLUSION

This suggests that the muscle strength generated per unit of muscle mass, which is reflected well by the serum creatinine level, is significantly reduced in DM hemodialysis patients. Therefore, our results show that the significantly lower serum creatinine levels in DM hemodialysis patients compared to non-DM hemodialysis patients may be explained by poor muscle quality rather than by reduced muscle mass or malnutrition.

Regions of arterial stenosis and clinical factors determining transcutaneous oxygen tension in patients with peripheral arterial disease

AIMS

Despite the clinical usefulness of transcutaneous oxygen tension (TcPO(2)) to assess the severity of limb ischemia, the factors determining TcPO(2) in patients with peripheral arterial disease (PAD) have not been fully clarified. We therefore examined the regions of arterial stenosis and clinical factors affecting lower-extremity TcPO(2).

METHODS

Resting TcPO(2) (REST-TcPO(2)) and postexercise TcPO(2) (Ex-TcPO(2)) in the calf region and the dorsalis pedis were measured simultaneously in 66 patients (132 limbs) with clinically suspected PAD, in whom angiography was also performed.

RESULTS

The peripheral arteries of the lower extremities were divided into five segments, and the impact of significant stenosis in each segment on ipsilateral TcPO(2) was evaluated by multiple regression analysis. In the calf region, significant stenosis of the proximal arteries (common-external iliac artery) revealed stronger involvement determining Ex-TcPO(2) than the peripheral segment (posterior tibial artery). In the dorsalis pedis, the peripheral segment (anterior tibial artery) more strongly determined Ex-TcPO(2) and REST-TcPO(2) than proximal segments. Age, creatinine, and diabetes were associated with REST-TcPO(2) of the calf region independent of arterial stenoses, while those of the dorsalis pedis were independently associated with age, and creatinine. In contrast, Ex-TcPO(2) in both regions was not independently associated with clinical factors, except for stenosis of the perfusing arteries.

CONCLUSION

The vascular lesions affecting TcPO(2) differ between the calf region (proximal > peripheral) and the dorsalis pedis (proximal < peripheral). In addition postexercise TcPO(2) is solely determined by stenosis of the perfusing arteries, while TcPO(2) at rest is affected by multiple clinical factors.

AGEs/RAGE in CKD: irreversible metabolic memory road toward CVD?

BACKGROUND

Cardiovascular disease is the major cause of death in patients with renal insufficiency, accounting for 50% of all deaths in renal replacement therapy patients. Mortality from cardiovascular diseases in these patients is approximately 9% per year, which is about 30 times the risk in the general population. So far, intensive interventions to the general risk factors, such as high LDL-cholesterol or C-reactive protein, have not been successful in improving their cardiovascular outcomes, suggesting that the beneficial effect of risk reduction may be overwhelmed by accumulated risk memorized by long-term exposure to oxidative stress during the progression of renal failure.

DESIGN

In this review, we propose that this irreversible memory effect in renal failure may be mediated by advanced glycation end-products (AGEs).

RESULTS

The generation of AGEs has been implicated to be deeply associated with increased oxidative stress. Moreover, interaction of the receptor for AGEs (RAGE) with AGEs leads to crucial biomedical pathway generating intracellular oxidative stress and inflammatory mediators, which could result in further amplification of the pathway involved in AGE generation. Several lines of evidence suggest that AGEs/RAGE axis can profoundly be involved in cardiovascular diseases. Recent advances in AGEs and RAGE measurements led us to be capable of understanding more about the role of AGEs/RAGE axis as a risk for cardiovascular diseases in patients with renal failure.

CONCLUSION

AGEs/RAGE axis could be a crucial mediator of oxidative stress in renal failure. RAGE could be not only a useful biomarker, but also a potentially therapeutic target to overcome the accumulated adverse metabolic memory in renal failure.

Fetuin-A and atherosclerotic calcified plaque in patients with type 2 diabetes mellitus

Fetuin-A is a multifunctional circulating glycoprotein. Among its roles, inhibition of ectopic calcification is a prominent feature. Low fetuin-A levels in dialysis patients are associated with cardiovascular mortality, possibly via accelerating vascular calcification. However, except for dialyzed conditions, a correlation between fetuin-A levels and vascular calcification remains controversial. Furthermore, any inhibitory effect of fetuin-A on atherosclerotic calcified plaques (CPs) remains unclear compared with its effect on medial artery calcification that is often found in dialyzed patients. Therefore, we examined the association between fetuin-A levels and atherosclerotic CPs. For this study, 416 consecutive patients with type 2 diabetes mellitus and without renal dysfunction were examined. We measured serum fetuin-A levels and investigated for the presence of CP in the common carotid and femoral arteries using ultrasonography. Fetuin-A levels were significantly lower in patients with CP than those without CP (262.6 +/- 56.7 and 281.5 +/- 64.6 microg/mL, respectively; P = .001). Multivariate logistic regression analysis showed that fetuin-A levels were inversely associated with the presence of CP (odds ratio = 0.753; 95% confidence interval, 0.608-0.933; P = .010). These results suggest that fetuin-A may inhibit the calcification of atherosclerotic plaques independently of the dialyzed condition.

The levels of somatostatin receptors in causative tumors of oncogenic osteomalacia are insufficient for their agonist to normalize serum phosphate levels

Oncogenic osteomalacia (OOM) is a rare disease characterized by renal phosphate wasting and osteomalacia and is caused by the secretion of fibroblast growth factor 23 (FGF-23) from causative tumors. Scintigraphy with octreotide, which binds to somatostatin receptors (SSTRs), is a useful way to locate causative tumors in OOM patients. However, the therapeutic effects of octreotide acetate are still controversial. Two OOM patients were administered octreotide acetate intramuscularly. Ten causative OOM tumors, including two resected from the patients participating in the octreotide administration study, were examined for expression of genes encoding SSTRs by quantitative real-time RT-PCR and immunohistochemistry. Octreotide therapy did not improve hypophosphatemia in either case, despite temporal decreases in FGF-23 levels in one patient. The mean expression levels of SSTR1, SSTR3, and SSTR5 were similar in the OOM and non-OOM tumors. Expression of SSTR2 was significantly higher in the OOM tumors than in the non-OOM tumors. Immunohistochemical examinations revealed the presence of SSTR2A, SSTR2B, and SSTR5 in both the OOM and non-OOM tumors. The expression of SSTR genes in OOM tumors contributes to positive imaging using octreotide scintigraphy. However, the levels of SSTRs seem to be insufficient for the octreotide therapy to improve hypophosphatemia. Further studies are needed to clarify the mechanisms by which FGF-23 secretion from OOM tumors is suppressed by octreotide acetate.

Brachial-ankle pulse wave velocity as an index of central arterial stiffness

AIM

Stiffness of the central arteries plays an important role in the pathophysiology of cardiovascular disease, and pulse wave velocity (PWV) of the aorta has been used as the standard measure of central arterial stiffness. An automated device for brachial-ankle (ba) PWV is available, although information is limited whether baPWV reflects the stiffness of central or peripheral arteries. We therefore addressed this question in the present study.

METHODS

The subjects were 2,806 consecutive participants in our non-invasive vascular laboratory, excluding those with an ankle-brachial index (ABI) lower than 0.95. PWV measurements were simultaneously performed using an automated device for the ba, heart-femoral (hf, aorta), heart-carotid (hc), heart-brachial (hb), and femoral-ankle (fa) segments. Correlational analyses were performed (1) among these PWV values, (2) between PWV and individual risk factors, and (3) between PWV and the Framingham risk score (FRS), a surrogate index for integrated cardiovascular risk.

RESULTS

The correlation of baPWV was the highest with hfPWV (r=0.796) and the lowest with hcPWV (r=0.541). Among the known factors preferentially affecting central arterial stiffness, higher age, diabetes mellitus, and chronic kidney disease (CKD) were also closely associated with increased baPWV. Finally, FRS was more closely correlated with hfPWV (r=0.613) and baPWV (r=0.609) than with hbPWV (r=0.523), hcPWV (r=0.509), and faPWV (r=0.393).

CONCLUSION

These results indicate that baPWV is an index of arterial stiffness showing similar characteristics to those of aortic PWV.

Preferential reduction of bone mineral density at the femur reflects impairment of physical activity in patients with low-activity rheumatoid arthritis

Bone mineral density (BMD) and factors influencing BMD in rheumatoid arthritis (RA) under good or moderate control were examined to assess management of osteoporosis in RA. BMD of the lumbar spine, femur, and distal radius was measured in 105 female patients with well-controlled RA. Laboratory and clinical variables associated with disease activity were measured in the same subjects, and correlations between these variables and BMD were evaluated. The RA patients showed a greater decrease in BMD of the femoral neck than of the lumbar spine. Age, Health Assessment Questionnaire (HAQ) score, and Larsen damage score had negative correlations with BMD of the femoral neck. In multiple regression analysis of the parameters associated with BMD of the femoral neck in simple regression analysis, an increase in HAQ score showed a negative correlation with BMD of the femoral neck. After initiation of treatment with alendronate (ALN), BMD of the femoral neck increased and correlated with improvement in HAQ score. A decrease in BMD of the femoral neck is a characteristic of RA. This suggests that muscle tonus has more effect than weight-bearing activity on BMD in patients with RA. BMD of the femoral neck is a useful index for general evaluation of RA patients.

Serum C-reactive protein and thioredoxin levels in subjects with mildly reduced glomerular filtration rate

Background

Chronic kidney disease (CKD) is a newly recognized high-risk condition for cardiovascular disease (CVD), and previous studies reported the changes in inflammation and oxidative stress in advanced stages of CKD. We compared the levels of serum biomarkers for inflammation and oxidative stress between subjects with normal and mildly reduced glomerular filtration rate (GFR).

Methods

The subjects were 182 participants of a health check-up program including those with normal (≥ 90 mL/min/1.73 m², N = 79) and mildly reduced eGFR (60-89 mL/min/1.73 m², N = 103) which was calculated based on serum creatinine, age and sex. We excluded those with reduced eGFR < 60 mL/min/1.73 m². No one had proteinuria. We measured serum levels of C-reactive protein (CRP) and thioredoxin (TRX) as the markers of inflammation and oxidative stress, respectively.

Results

As compared with subjects with normal eGFR, those with mildly reduced eGFR had increased levels of both CRP and TRX. Also, eGFR was inversely correlated with these biomarkers. The associations of eGFR with these biomarkers remained significant after adjustment for age and sex. When adjustment was done for eight possible confounders, CRP showed significant association with systolic blood pressure, high density lipoprotein cholesterol (HDL-C) and non-HDL-C, whereas TRX was associated with sex significantly, and with eGFR and systolic blood pressure at borderline significance.

Conclusions

We showed the increased levels of CRP and TRX in subjects with mildly reduced eGFR. The eGFR-CRP link and the eGFR-TRX link appeared to be mediated, at least partly, by the alterations in blood pressure and plasma lipids in these subjects.

A functional polymorphism in the disrupted-in schizophrenia 1 gene is associated with chronic fatigue syndrome

AIMS

Disrupted-in schizophrenia 1 (DISC1), identified in a pedigree with a familial psychosis with the chromosome translocation (1:11), is a putative susceptibility gene for psychoses such as schizophrenia and major depressive disorder (MDD). Patients with chronic fatigue syndrome (CFS) report having continuous severe fatigue and many overlapping symptoms with MDD; however, the mechanism and effective treatment of CFS are still unclear. We focused on the overlapping symptoms between CFS and MDD and performed an association study of the functional single-nucleotide polymorphism (SNP) in the DISC1 gene with CFS.

MAIN METHODS

Venous blood was drawn from CFS patients and controls and genomic DNA was extracted from the whole blood according to standard procedures. Ser704Cys DISC1 SNP was genotyped using the TaqMan 5'-exonuclease allelic discrimination assay.

KEY FINDINGS

We found that the Cys704 allele of Ser704Cys SNP was associated with an increased risk of CFS development compared with the Ser704 allele.

SIGNIFICANCE

DISC1 Ser704Cys might be a functional variant that affects one of the mechanisms implicated in the biology of CFS. Some patients with CFS showed a phenotype similar to that of patients with MDD, but further studies are needed to clarify the biological mechanism, because this study is of a rather preliminary nature. Despite the variety of patients with CFS, DISC1 Ser704Cys has an association with CFS, which may also suggest that DISC1 plays a central role in the induction of various psychiatric diseases.

Association of glycated albumin, but not glycated hemoglobin, with calcaneus quantitative ultrasound in male hemodialysis patients with type 2 diabetes mellitus

Sustained high glucose impairs bone metabolism in patients with type 2 diabetes mellitus (T2DM). In this study, the relationship between glycemic control and bone metabolism was examined in male hemodialysis (HD) patients with T2DM. To avoid the effect of menstruation and the menstrual cycle, obesity, and glycosuria-induced hypercalciuria on bone metabolism, male anuric nonobese HD patients with T2DM (n = 42) were enrolled. Calcaneus stiffness index (SI) was determined using ultrasound after HD session. Casual plasma glucose (PG), glycated hemoglobin (HbA(1c)), and glycated albumin (GA) were measured before the HD session. In simple regression analysis, log PG (r = -0.333, P < .05) and log GA (r = -0.350, P < .05), but not log HbA(1c) (r = -0.134, P = .3985), exhibited significant and negative correlations with calcaneus SI. In multiple regression analysis including log BMI, log cCa x Pi product, and log PG, log PG was associated significantly in a negative manner with calcaneus SI, in addition to log cCa x Pi product. When log PG was replaced with log GA or log HbA(1c), log GA, but not log HbA(1c), emerged as a significant factor associated. The mechanism as to why HbA(1c) failed to associate could be explained by its false reduction by erythropoietin injection. The present study supported the notion of GA as an appropriate indicator for glycemic control in HD patients with T2DM. Furthermore, it is suggested that poor glycemic control might be a significant factor toward decreasing calcaneus SI in T2DM HD patients.

Fatigue is a predictor for cardiovascular outcomes in patients undergoing hemodialysis

BACKGROUND AND OBJECTIVES

Despite potential significance of fatigue and its underlying components in the occurrence of cardiovascular diseases, epidemiologic data showing the link are virtually limited. This study was designed to examine whether fatigue symptoms or fatigue's underlying components are a predictor for cardiovascular diseases in high-risk subjects with ESRD.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

788 volunteer patients under hemodialysis therapy (506 male, 282 female) completed the survey between October and November 2005, with the follow-up period up to 26 months to monitor occurrence of fatal or nonfatal cardiovascular events. The questionnaire consisted of 64 questions, and promax rotation analysis of the principal component method conceptualized eight fatigue-related factors: fatigue itself, anxiety and depression, loss of attention and memory, pain, overwork, autonomic imbalance, sleep problems, and infection.

RESULTS

14.7% of the patients showed fatigue scores higher than twice the SD of the mean for healthy volunteers. These highly fatigued patients exhibited a significantly higher risk for cardiovascular events (hazard ratio: 2.17; P < 0.01), with the relationship independent of the well-known risk factors, including age, diabetes, cardiovascular disease history, and inflammation and malnutrition markers. Moreover, comparisons of the risk in key subgroups showed that the risk of high fatigue score for cardiovascular events was more prominent in well-nourished patients, including lower age, absence of past cardiovascular diseases, higher serum albumin, and high non-HDL cholesterol.

CONCLUSIONS

Fatigue can be an important predictor for cardiovascular events in patients with ESRD, with the relationship independent of the nutritional or inflammatory status.