Brain atrophy in type 2 diabetes: regional distribution and influence on cognition

OBJECTIVE

Type 2 diabetes (T2DM) is associated with brain atrophy and cerebrovascular disease. We aimed to define the regional distribution of brain atrophy in T2DM and to examine whether atrophy or cerebrovascular lesions are feasible links between T2DM and cognitive function.

RESEARCH DESIGN AND METHODS

This cross-sectional study used magnetic resonance imaging (MRI) scans and cognitive tests in 350 participants with T2DM and 363 participants without T2DM. With voxel-based morphometry, we studied the regional distribution of atrophy in T2DM. We measured cerebrovascular lesions (infarcts, microbleeds, and white matter hyperintensity [WMH] volume) and atrophy (gray matter, white matter, and hippocampal volumes) while blinded to T2DM status. With use of multivariable regression, we examined for mediation or effect modification of the association between T2DM and cognitive measures by MRI measures.

RESULTS

T2DM was associated with more cerebral infarcts and lower total gray, white, and hippocampal volumes (all P < 0.05) but not with microbleeds or WMH. T2DM-related gray matter loss was distributed mainly in medial temporal, anterior cingulate, and medial frontal lobes, and white matter loss was distributed in frontal and temporal regions. T2DM was associated with poorer visuospatial construction, planning, visual memory, and speed (P ≤ 0.05) independent of age, sex, education, and vascular risk factors. The strength of these associations was attenuated by almost one-half when adjusted for hippocampal and total gray volumes but was unchanged by adjustment for cerebrovascular lesions or white matter volume.

CONCLUSIONS

Cortical atrophy in T2DM resembles patterns seen in preclinical Alzheimer disease. Neurodegeneration rather than cerebrovascular lesions may play a key role in T2DM-related cognitive impairment.

Expression of the MEN-1 gene in a large kindred with multiple endocrine neoplasia type 1

In 1983 a large family with MEN-1 (designated Tasman 1) was identified in Tasmania. Kindred screening and case follow-up over the subsequent 15 years has yielded data on over 160 MEN-1-affected patients. Hyperparathyroidism is present in over 60% of gene carriers by age 20 years and 95% by age 30 years. Hyperplasia is the characteristic pathological finding. Kaplan-Meier analysis indicates hyperparathyroidism recurs in the majority of patients despite near-total parathyroidectomy. Gastrinoma, 'nonfunctioning' pancreatic adenoma and insulinoma occur in up to 60, 50 and 10% of patients, respectively. Metastatic gastroenteropancreatic (GEP) tumours develop in up to 35% of family members, being frequent in some branches of Tasman 1, whilst rare in others. Pituitary disease developed in 19% of patients. Prolactinoma and 'nonfunctioning' adenoma account for 76 and 24%, respectively, of pituitary abnormalities. Prolactinomas exhibit clustering within branches of the Tasman 1 kindred. Adrenal adenomas occur in 36% of patients. The majority of adrenal lesions are benign and nonsecretory and develop in association with pancreatic neoplasia. Carcinoid tumours are uncommon but important malignancies. Malignant thymic carcinoid occurs in male patients, whereas bronchial carcinoid occurs predominantly in women. Prior to recognition of MEN-1 in Tasman 1, complications of hyperparathyroidism and malignancy accounted for the majority of patient mortality. Since commencement of prospective screening, malignant GEP tumours and cardiovascular disease have become the most prevalent causes of death amongst MEN-1-affected patients.

Adrenal lesions in a large kindred with multiple endocrine neoplasia type 1

OBJECTIVE

To review the prevalence and natural history of adrenal lesions occurring in patients from a single kindred with multiple endocrine neoplasia type 1 (MEN-1).

DESIGN

Case series.

SETTING

Tertiary referral center.

PATIENTS

Medical records of 33 patients from the Tasman 1 MEN-1 kindred who had undergone abdominal computed tomographic (CT) scanning were reviewed. In 30 patients, the results of abdominal ultrasonographic examinations were available for correlation with CT scan. Computed tomographic and ultrasound scans of 18 patients were reviewed by a radiologist blinded to the patients' clinical details. Three patients underwent adrenalectomy, and the histopathologic material was reviewed.

MAIN OUTCOME MEASURES

Computed tomographic and ultrasound scans.

RESULTS

Adrenal lesions were detected in 12 patients (36%) by CT scan examination. Ultrasound imaged 58% of these lesions. Pancreatic lesions were present in all cases of adrenal disease. Follow-up was available for 8 patients with adrenal disease. Over 5.5 years, 6 patients (75%) had stable disease, 1 patient had an adrenal lesion that enlarged by 5 mm, and 1 patient had a lesion that enlarged by 50 mm. Adrenal histopathologic material was available in 3 patients. Macronodular cortical hyperplasia was present in 2 patients and a cortical adenoma present in 1 patient. Another kindred had bilateral macronodular cortical hyperplasia at autopsy.

CONCLUSIONS

Adrenal lesions are common in MEN-1 and occur in association with pancreatic disease. Abdominal CT scan is more sensitive than ultrasonographic examination in detecting adrenal disease. Primary hypersecretory syndromes of the adrenal glands appear to be rare, and the majority of lesions follow an indolent clinical course.

The outcome of subtotal parathyroidectomy for the treatment of hyperparathyroidism in multiple endocrine neoplasia type 1

BACKGROUND

The efficacy of subtotal parathyroidectomy for the treatment of hyperparathyroidism in multiple endocrine neoplasia type 1 (MEN 1) is unclear. The long-term outcome and optimal timing of operation remain controversial.

OBJECTIVE

To determine the long-term outcome of parathyroidectomy for primary hyperparathyroidism in the presence of MEN 1.

DESIGN

Case series and retrospective analysis.

SETTING

Tertiary referral center.

PATIENTS

Patients with MEN 1 from 2 families.

INTERVENTIONS

Subtotal parathyroidectomy, ie, resection of 3 1/2 parathyroid glands from each patient.

MAIN OUTCOME MEASURES

Recurrence of hyperparathyroidism.

RESULTS

Thirty-seven patients underwent subtotal parathyroidectomy. Overall, persistent postoperative hypoparathyroidism developed in 24%, normocalcemia was maintained in 46%, and hyperparathyroidism recurred in 30%. However, after adjustment for the duration of follow-up (by using the Kaplan-Meier method), the cumulative recurrence rates for hyperparathyroidism were 15% at 2 years, 23% at 4 years, 55% at 8 years, and 67% after 8 years. Early recurrence of hyperparathyroidism (within 5 years of operation) was less likely to develop in patients in whom ionized calcium levels of 1.00 mmol/L (4.00 mg/dL) or less were achieved during the perioperative period than in patients in whom this degree of hypocalcemia failed to develop (P=.01).

CONCLUSIONS

While relatively long periods of disease remission are possible after subtotal parathyroidectomy, our results indicate that recurrent hyperparathyroidism eventually develops in most patients with MEN 1.

Phenotype and phenocopy: the relationship between genotype and clinical phenotype in a single large family with multiple endocrine neoplasia type 1 (MEN 1)

BACKGROUND

The majority of reports describing the natural history and prognosis of multiple endocrine neoplasia type 1 (MEN 1) utilize phenotypic rather than molecular genetic criteria to establish a diagnosis of MEN 1.

OBJECTIVES AND PATIENTS

We sought to determine the spectrum of endocrine abnormality amongst 152 members (64 gene carriers and 88 noncarriers) of a large MEN 1 family in whom a determination of MEN 1 status had previously been made by phenotype screening. The predictive utility of both clinical and molecular screening techniques are described.

RESULTS

A novel IVS2-3 (C-G) MEN1 mutation was identified in affected members of this family. Seven (10%) of 71 individuals satisfying clinical diagnostic criteria for MEN 1 were found to be genetically negative (excluded by mutation analysis and haplotyping) for MEN 1. These cases of MEN 1 phenocopy comprised four cases of primary hyperparathyroidism, two 'nonsecretory' pituitary adenoma and one case of coincident prolactinoma and hyperparathyroidism. Three of the patients with hyperparathyroidism had previously required parathyroidectomy and each had achieved normocalcaemia following parathyroid resection. Predictive genetic testing prospectively identified three children with the MEN 1 genotype. Serum calcium was normal at the time of their initial molecular genetic diagnosis. In each case hyperparathyroidism subsequently developed during adolescence.

CONCLUSION

Multiple endocrine neoplasia type 1 phenocopy is an important differential diagnosis in patients exhibiting an multiple endocrine neoplasia type 1 phenotype. This is a relevant consideration, particularly when the diagnosis of multiple endocrine neoplasia type 1 is made using sensitive, but nonspecific, criteria such as mild hyperparathyroidism, pituitary micoadenoma, and hyperprolactinaemia. Confirmatory genetic testing should be undertaken to confirm clinical diagnoses of multiple endocrine neoplasia type 1.

Osteoporosis in multiple endocrine neoplasia type 1: severity, clinical significance, relationship to primary hyperparathyroidism, and response to parathyroidectomy

BACKGROUND

Sporadic primary hyperparathyroidism (PHPT) occurs most frequently in postmenopausal women. Multiple endocrine neoplasia type 1 (MEN 1) is an autosomal-dominant disease in which mild to moderate PHPT develops in most gene carriers by 20 years of age. Primary hyperparathyroidism associated with MEN 1 is typically recurrent, despite initially successful subtotal parathyroidectomy. Osteoporosis is considered a complication of sporadic PHPT and an indication for parathyroidectomy. In the setting of MEN 1, however, the relationship of bone mass to PHPT, fracture risk, and parathyroidectomy is unknown.

HYPOTHESIS

Parathyroidectomy improves bone mineral density for patients with primary hyperparathyroidism in the setting of MEN 1.

DESIGN

Case series.

SETTING

Tertiary referral center.

PATIENTS

Twenty-nine women with MEN 1 belonging to a single family with a history of MEN 1.

INTERVENTIONS

Parathyroidectomy.

MAIN OUTCOME MEASURES

Bone mineral density (BMD) and history of skeletal fracture.

RESULTS

Osteopenia and osteoporosis were diagnosed in 41% and 45% of patients, respectively. Forty-four percent of patients with uncontrolled PHPT had severe osteopenia (T score, <-2.0) by 35 years of age. Reduction in BMD was greatest at the femoral neck. Reduced BMD was associated with an increased likelihood of skeletal fracture (P = .05). Patients with uncontrolled PHPT had lower femoral neck and lumbar spine BMDs than those in whom PHPT was controlled by parathyroidectomy (P = .005 and .02, respectively). Successful parathyroidectomy improved femoral neck and lumbar spine BMDs by a mean +/- SEM of 5.2% +/- 2.5% and 3.2% +/- 2.9%, respectively.

CONCLUSIONS

Osteoporosis is a frequent and early complication of PHPT in MEN 1. Despite difficulty in achieving a cure of PHPT in MEN 1, parathyroidectomy has an important role in the optimization of BMD for patients with MEN 1.

Vitamin D insufficiency in adolescent males in Southern Tasmania: prevalence, determinants, and relationship to bone turnover markers

There are limited data on vitamin D insufficiency in healthy children. The aim of this study was to describe the prevalence and determinants of vitamin D insufficiency and its association with bone turnover in adolescent boys (N = 136, mean age 16 years). Sun exposure and physical activity were assessed by questionnaire. Vitamin D stores were assessed by serum 25-hydroxyvitamin D3 (25[OH]D3). Bone turnover was assessed by bone-specific alkaline phosphatase (BAP) and urinary pyridinoline (PYR) to creatinine (Cr) ratio (mmol PYR/micromol Cr). The mean 25(OH)D3 level was low (44 nmol/l; 68% < 50 nmol/l; range, 16-87) and was associated with self-reported sun exposure on winter weekends (r = 0.23, p = 0.01), school holidays (r = 0.22, p = 0.01), and weekdays (r = 0.17, p = 0.05). It was also associated with number of sports (r = 0.34, p < 0.001) and vigorous activity (r = 0.22, p = 0.01) but not television, computer, and video watching (r = -0.04, p = 0.68). In multivariate analysis, number of sports but not total sun exposure remained significantly associated with 25(OH)D3. Furthermore, 25(OH)D3 was significantly associated with BAP in cutpoint analysis (cutpoint 55 nmol/l, p = 0.03) but not continuous analysis (r = -0.12, p = 0.16) and PYR in both forms (r = -0.23, p = 0.01, cutpoint 43 nmol/l, p = 0.01). In conclusion, vitamin D insufficiency is common in healthy adolescent boys in winter in our setting, is primarily derived from sports-related sun exposure, and is associated with bone turnover markers. These data suggest that a 25(OH)D3 level of at least 43-55 nmol/l is required for optimal bone health in children.

Vitamin D levels in prepubertal children in Southern Tasmania: prevalence and determinants

OBJECTIVE

To describe the prevalence and determinants of 25-hydroxy D3(25(OH)D) in children.

DESIGN

Cross-sectional study.

SETTING

Southern Tasmania between June and November 1997.

SUBJECTS

Two hundred and one 8-y old male and female children taking part in a cohort study whose principal endpoints were blood pressure and high-density lipoprotein (HDL) cholesterol.

RESULTS

The mean 25(OH)D level was 79 nmol/l (s.d. 29.5, median 73, range 12-222). Boys had higher levels than girls (82.1 vs 72.8 nmol/l, P=0.02). 25(OH)D was associated with sunlight exposure in winter school holidays (r=0.20, P=0.005) and winter weekends (r=0.16, P=0.02), the month after school holidays (87.5 vs 69.5 nmol, P<0.0001) and body mass index (r=-0.23, P=0.001). Dietary intake of vitamin D was low (mean 40 IU/day, range 5.2-384) and was not associated with 25(OH)D levels (r=0.01, P=0.91). Variation in skin melanin density was weakly associated with 25(OH)D (r=0.09, P=0.19).

CONCLUSIONS

Sunlight is the major determinant of vitamin D stores in our population. Neither variation in skin type within Caucasians nor diet modified this association to any significant extent. Extrapolation of these findings to sunlight bone mass associations in a very similar population suggests that a minimum level of around 50 nmol/l in the population is required for optimal bone development in prepubertal children but this needs to be confirmed with further controlled trials of vitamin D supplementation and bone mass.

SPONSORSHIP

Arthritis Foundation of Australia, Roche Pharmaceuticals.

Skeletal Muscle Microvascular-Linked Improvements in Glycemic Control From Resistance Training in Individuals With Type 2 Diabetes

OBJECTIVE

Insulin increases glucose disposal in part by enhancing microvascular blood flow (MBF) and substrate delivery to myocytes. Insulin's microvascular action is impaired with insulin resistance and type 2 diabetes. Resistance training (RT) improves glycemic control and insulin sensitivity, but whether this improvement is linked to augmented skeletal muscle microvascular responses in type 2 diabetes is unknown.

RESEARCH DESIGN AND METHODS

Seventeen (11 male and 6 female; 52 ± 2 years old) sedentary patients with type 2 diabetes underwent 6 weeks of whole-body RT. Before and after RT, participants who fasted overnight had clinical chemistries measured (lipids, glucose, HbA_1c, insulin, and advanced glycation end products) and underwent an oral glucose challenge (OGC) (50 g × 2 h). Forearm muscle MBF was assessed by contrast-enhanced ultrasound, skin MBF by laser Doppler flowmetry, and brachial artery flow by Doppler ultrasound at baseline and 60 min post-OGC. A whole-body DEXA scan before and after RT assessed body composition.

RESULTS

After RT, muscle MBF response to the OGC increased, while skin microvascular responses were unchanged. These microvascular adaptations were accompanied by improved glycemic control (fasting blood glucose, HbA_1c, and glucose area under the curve [AUC] during OGC) and increased lean body mass and reductions in fasting plasma triglyceride, total cholesterol, advanced glycation end products, and total body fat. Changes in muscle MBF response after RT significantly correlated with reductions in fasting blood glucose, HbA_1c, and OGC AUC with adjustment for age, sex, % body fat, and % lean mass.

CONCLUSIONS

RT improves OGC-stimulated muscle MBF and glycemic control concomitantly, suggesting that MBF plays a role in improved glycemic control from RT.

Two families with an autosomal dominant inheritance pattern for papillary carcinoma of the thyroid

BACKGROUND

Papillary carcinoma of the thyroid (PTC) is the most prevalent malignancy of the thyroid gland. Although the majority of lesions are sporadic tumors, an established relationship exists between familial adenomatous polyposis (FAP) and PTC. Moreover, some authors postulate the existence of familial PTC as a distinct entity. Evidence for this is limited, however, there being few well characterized descriptions of pedigrees with high prevalence of PTC.

AIMS

The objective of the present study was to examine an apparent heritable predisposition to PTC occurring in two Tasmanian families in which PTC occurs commonly.

METHODS

Pedigree charts were constructed for both families and the medical records of the members reviewed.

RESULTS

In Pedigree I, 7 of 25 members had PTC (6 of these had coexisting multinodular goiter (MNG), and 11 others had MNG. In Pedigree II, identical male twins and their daughters had PTC.

CONCLUSIONS

In both families there is evidence of autosomal dominant inheritance of PTC. The association of PTC with MNG suggests a possible role for MNG in tumor pathogenesis in hereditary PTC. The majority of the patients were diagnosed with PTC before commencement of prospective screening, indicating clinically relevant disease in the families described.

The influence of gestational stage on urinary iodine excretion in pregnancy

INTRODUCTION

Median urinary iodine concentration (UIC) is the most commonly used indicator of population iodine nutrition. However, its validity as an indicator of dietary intake relies on a stable relationship between dietary iodine intake and urinary excretion. Physiological alterations in normal pregnancy, such as increased glomerular filtration rate, potentially invalidate UIC as an assessment tool in pregnancy.

OBJECTIVE

The objective of the study was to document the impact of advancing gestation on UIC in normal pregnancy and determine whether the current reference intervals for general population iodine monitoring are appropriate for use in the context of pregnancy.

DESIGN

Tasmania has a well-described history of mild iodine deficiency (school-age median UIC of 84 microg/liter). We assessed UIC in 759 urine samples from 431 women attending the Antenatal Clinic at the Royal Hobart Hospital, Tasmania's primary teaching hospital.

MAIN OUTCOME

The overall median UIC during pregnancy was 75 microg/liter (95% confidence interval 70.03-79.97 microg/liter) at a median gestation of 19.4 wk. Stratification by gestation, however, revealed a dynamic relationship between ioduria and gestation. Median UIC was elevated in early pregnancy and subsequently declined with advancing gestation.

CONCLUSION

In this mildly iodine-deficient population, current reference intervals for UIC overestimated the adequacy of iodine nutrition during the first and early second trimester of pregnancy. Gestation-specific UIC reference intervals are required to classify iodine nutrition during pregnancy. This is particularly important in populations with borderline iodine deficiency.

A population-based study of the relationship between salt intake, bone resorption and bone mass

OBJECTIVE

To explore the relationship between urinary sodium (the best measure of salt intake), urinary calcium, urinary deoxypyridinoline (DPYR) and bone mass.

DESIGN

Cross-sectional study.

SETTING

Population based sample of healthy Hobart residents.

SUBJECTS

One hundred and fifty-four (M = 34, F = 120) subjects invited to take part from a systematic sample of the electoral roll and a single newspaper advertisement.

RESULTS

In both sexes, urinary sodium correlated moderately with urinary DPYR (r = 0.32, P < 0.0001) and urinary calcium (r = 0.37, P < 0.0001). In multivariate analysis, the combination of urinary sodium, total body bone area, age and sex explained 22% of the variation in log-transformed DPYR (P < 0.00001). In univariate analysis, both urinary sodium and urinary DPYR were strongly associated with bone mineral content and bone mineral density at all sites but this association disappeared after adjustment for confounders particularly body weight.

CONCLUSIONS

This study has shown that salt intake is associated with markers of bone resorption in a population-based sample of males and females and appears likely to be a risk factor for osteoporosis despite the lack of a demonstrable association between bone mass and a single measure of urinary sodium excretion. Further studies are needed to define the effect of salt intake on bone mass and fractures more clearly. These studies will need to be either longitudinal or interventional in design with repeated measures of urinary sodium so that habitual sodium intake can be accurately assessed and regression dilution bias can be minimised.

Refractory amiodarone-associated thyrotoxicosis: an indication for thyroidectomy

BACKGROUND

Tasmania is an area of endemic iodine deficiency. Amiodarone is a class III anti-arrhythmic drug that is widely used for the management of ventricular and supraventricular tachydysrhythmias. Individuals from areas of endemic iodine deficiency appear more likely to manifest hyperthyroidism following amiodarone therapy, whereas hypothyroidism is a more frequent complication in iodine-replete communities.

METHODS

Cases series. The clinical and biochemical response to medical and surgical management of five consecutive Tasmanian patients presenting with severe type-II amiodarone-associated thyrotoxicosis was reviewed.

RESULTS

Five patients were identified. Combinations of antithyroid therapy including propylthiouracil, lithium carbonate, dexamethasone and cholestyramine were used. Thyroidectomy was required in two cases (40%) due to severe unremitting thyrotoxicosis despite combined drug regimens. Anaesthesia and total thyroidectomy were undertaken without complication despite the presence of severe hyperthyroidism at the time of surgery. In both cases thyroid histopathology demonstrated degenerative and destructive follicular lesions with multinuclear cell infiltrate and focal fibrosis.

CONCLUSION

Amiodarone-associated thyrotoxicosis may be severe and refractory to medical therapy. Despite the potential risks of anaesthesia associated with uncontrolled thyrotoxicosis, thyroidectomy should be considered in the setting of life-threatening thyrotoxicosis.

Enteropancreatic malignancy associated with multiple endocrine neoplasia type 1: risk factors and pathogenesis

BACKGROUND

Enteropancreatic malignancy is an important cause of morbidity and mortality associated with multiple endocrine neoplasia type 1 (MEN 1). However, the risk factors and mechanisms of the tumorigenesis of this malignancy are poorly understood.

METHODS

The authors conducted a retrospective study of factors associated with the development of malignant enteropancreatic tumor in 69 patients with MEN 1 belonging to a single family.

RESULTS

Metastatic enteropancreatic tumor and gastrinoma were identified in 20% and 36% of patients, respectively. Compared with MEN 1 patients who did not have an immediate family history of enteropancreatic malignancy, MEN 1 patients with a first-degree relative affected by enteropancreatic malignancy had an increased risk of developing disseminated tumor (odds ratio, 3.7; P < 0.05). In addition, hypergastrinemia and advanced age were both associated with a significant increase in the risk of enteropancreatic malignancy. Elevated serum glycoprotein alpha subunit levels were associated with enterochromaffin-like cell hyperplasia, gastric carcinoid formation, and disseminated enteropancreatic tumor in hypergastrinemic patients (P < 0.05).

CONCLUSIONS

Disease modifier factors act in concert with the MEN 1 gene to modulate the development of enteropancreatic neoplasia. It is possible to identify MEN 1 patients at high risk for developing aggressive enteropancreatic tumors. Heritable disease modifier factor(s) affecting enteropancreatic malignancy appear to reside at loci distinct from that of the MEN 1 gene.

Vitamin D deficiency and secondary hyperparathyroidism: clinical and biochemical associations in older non-institutionalised Southern Tasmanians

AIM

To determine the prevalence and associations of vitamin D (25-OHD) deficiency in a sample of older Tasmanian subjects.

METHODS

A cross-sectional survey of: 109 patients with a mean age of 79 years (range 60-101 years) consecutively admitted to a short stay geriatric rehabilitation ward; 52 community dwelling subjects with a mean age of 75 years (range 64-88 years). Subjects answered a questionnaire, had anthropometric measurements and underwent venepuncture.

RESULTS

The main outcome measure was 25 hydroxy vitamin D (25-OHD) level with deficiency defined as <28 nmol/L. Vitamin D deficiency was found in 67% and secondary hyperparathyroidism in 49% of the hospitalised group. Vitamin D deficiency was also found in 17% of the community group, in particular one in three residents of Independent Living Units was deficient. Subjects who were deficient were older (80 years vs 76 years [p<0.001]), had lower body mass index (23.7 kg/m2 vs 25.9 kg/m2 [p<0.001]) and had a lower serum albumin (35 gm/L vs 39 gm/L [p<0.001]). Deficient subjects had poorer physical functional status (p=0.02) and lower activity levels (p<0.001) and reported less habitual sun exposure (p<0.001). Biochemical measures such as parathyroid hormone, alkaline phosphatase and calcium were weakly predictive of vitamin D levels. By stepwise multiple regression analysis, the only significant predictors of vitamin D levels were the Frenchay Activity Index, albumin and calcium.

CONCLUSION

Vitamin D deficiency and secondary hyperparathyroidism is common in community living older people who are hospitalised in Southern Tasmania and is associated with increasing age, poor physical function and activity and low reported sun exposure.

Pre-emptive (neo-adjuvant) chemotherapy prior to radical radiotherapy for fit septuagenarians with bladder cancer: age itself is not a contra-indication

Advanced age has often been cited as a contra-indication to the use of cytotoxic chemotherapy or aggressive combined treatment regimens. Fifteen patients, aged between 70 and 79 years (mean 73.1), have been treated for high grade, invasive bladder cancer using neoadjuvant intravenous cisplatin (80-100 mg/m2) plus radical radiotherapy (60 Gy in 6 weeks). Objective response was achieved in 14 patients. The median survival was 22 months, with 6 patients surviving 3 years or longer. Acute and late side effects were not excessive (no cases of W.H.O. grade IV toxicity), as demonstrated by clinical examination and the use of questionnaires (including linear analogue self-assessment scales) to assess quality of life. This aggressive treatment programme can achieve a high remission rate and prolonged survival in elderly patients with high risk bladder cancer without causing excessive morbidity.

Admission blood glucose predicts mortality and length of stay in patients admitted through the emergency department

BACKGROUND

Hyperglycaemia has been associated with adverse outcomes in several different hospital populations.

AIM

The aim of this study was to investigate the relationship between admission blood glucose level (BGL) and outcomes in all patients admitted through the emergency department.

METHODS

This study was a retrospective observational cohort study from an Australian tertiary referral hospital. Patients admitted in the first week of each month from April to October 2012 had demographic data, co-morbidities, BGL, intensive care unit admission, length of stay and dates of death recorded. Factors associated with outcomes were assessed by multi-level mixed-effects linear regression.

RESULTS

Admission BGL was recorded for 601 admissions with no diagnosis of diabetes and for 219 admissions diagnosed with type 2 diabetes (T2DM). In patients with no diagnosis of diabetes, admission BGL was associated with in-hospital and 90-day mortality (P < 0.001). After multivariate analysis, BGL greater than 11.5 mmol/L was significantly associated with increased mortality at 90 days (P < 0.05). In patients with T2DM increased BGL on admission was not associated with in-hospital or 90-day mortality but was associated with length of hospital stay (β: 0.22 days/mmol/L; 95% confidence interval 0.09-0.35; P < 0.001), although this association was lost on multivariable analysis. In patients with T2DM, increased coefficient of variation of BGL was also positively associated with length of hospital stay in an almost dose-dependent fashion (P < 0.001).

CONCLUSION

Admission BGL was independently associated with increased mortality in patients with no diagnosis of diabetes. Glycaemic variability was associated with increased length of hospital stay in patients with T2DM.

Oral glucose challenge impairs skeletal muscle microvascular blood flow in healthy people

Skeletal muscle microvascular (capillary) blood flow increases in the postprandial state or during insulin infusion due to dilation of precapillary arterioles to augment glucose disposal. This effect occurs independently of changes in large artery function. However, acute hyperglycemia impairs vascular function, causes insulin to vasoconstrict precapillary arterioles, and causes muscle insulin resistance in vivo. We hypothesized that acute hyperglycemia impairs postprandial muscle microvascular perfusion, without disrupting normal large artery hemodynamics, in healthy humans. Fifteen healthy people (5 F/10 M) underwent an oral glucose challenge (OGC, 50 g glucose) and a mixed-meal challenge (MMC) on two separate occasions (randomized, crossover design). At 1 h, both challenges produced a comparable increase (6-fold) in plasma insulin levels. However, the OGC produced a 1.5-fold higher increase in blood glucose compared with the MMC 1 h postingestion. Forearm muscle microvascular blood volume and flow (contrast-enhanced ultrasound) were increased during the MMC (1.3- and 1.9-fold from baseline, respectively, P < 0.05 for both) but decreased during the OGC (0.7- and 0.6-fold from baseline, respectively, P < 0.05 for both) despite a similar hyperinsulinemia. Both challenges stimulated brachial artery flow (ultrasound) and heart rate to a similar extent, as well as yielding comparable decreases in diastolic blood pressure and total vascular resistance. Systolic blood pressure and aortic stiffness remained unaltered by either challenge. Independently of large artery hemodynamics, hyperglycemia impairs muscle microvascular blood flow, potentially limiting glucose disposal into skeletal muscle. The OGC reduced microvascular blood flow in muscle peripherally and therefore may underestimate the importance of skeletal muscle in postprandial glucose disposal.

The effect of a fracture protocol on hospital prescriptions after minimal trauma fractured neck of the femur: a retrospective audit

Effective therapies for the treatment of osteoporosis and fracture have been available for a number of years. Despite this, there are numerous reports indicating very low uptake rates in those admitted to hospital with fracture. The aim of this retrospective audit was to assess the impact of a fracture protocol on inpatient prescriptions of osteoporosis therapy. A fracture protocol was arrived at by consensus and was based on recommendations from the Australian Fracture Prevention Summit, which included specific advice on the commencement in hospital of calcium, vitamin D, synthetic estrogen receptor modulators (SERMs) and bisphosphonates. We studied subjects who were treated for fractured neck of the femur at Royal Hobart Hospital from March 2002 to March 2004 and included 161 prior to the start of the protocol and 93 after. As compared to the baseline period, subjects after the introduction of the protocol had higher rates of in-hospital prescription for any treatment (58 vs. 36%, P <0.01), calcium (51 vs. 26%, P <0.01), vitamin D (48 vs. 29%, P <0.01) and oral bisphosphonates (24 vs. 5%, P <0.01), but not SERMs as expected (1 vs. 1%, P =0.70). Additional factors affecting the decision to start any treatment included in-hospital death (OR 0.16, 95% CI 0.05-0.49), dementia (OR 0.39, 95% CI 0.21-0.74), a trend for female sex (OR 1.79, 95%CI 0.96-3.36), but not age. In conclusion, a structural approach to changing hospital policy from the top down is effective at substantially increasing the usage of effective therapy after fractured neck of the femur.

Preoperative sestamibi scanning and surgical findings at bilateral, unilateral, or minimal reoperation for recurrent hyperparathyroidism after subtotal parathyroidectomy in patients with multiple endocrine neoplasia type 1

HYPOTHESES

Preoperative parathyroid radioisotope scanning is of little or no value in patients with multiple endocrine neoplasia type 1 when 4 or more hypertrophied glands are present. Scanning using technetium Tc 99m sestamibi and single photon emission computed tomography will achieve a high level of sensitivity and specificity after 3 or more glands have previously been removed, justifying limited surgical reexploration.

DESIGN

In a prospective study, the preoperative documented report of the predicted site of residual parathyroid was compared with the surgical findings in 13 patients having 19 scans and 17 reoperations.

SETTING

All patients belonged to one family, previously described as Tasman family 1, and were confirmed by genetic testing as having multiple endocrine neoplasia type 1. In 10 of 13 patients, reexploration was being undertaken more than 10 years after the first operation.

MAIN OUTCOME MEASURES

Scanning was regarded as successful when the documented preoperative report correctly predicted the side and quadrant in which a gland was found at surgery. Surgery was regarded as successful when calcium levels decreased to or below normal levels and were maintained.

RESULTS

All 13 scans before first reexploration were successful in identifying the location of a residual parathyroid. From a statistical viewpoint, this equates to 100% sensitivity and 92% specificity. However, despite accurate localization of 1 residual gland in every patient, 7 supernumerary glands in 4 patients and 1 parathyroid remnant in a fifth patient were not localized so that sensitivity in locating all glands in every patient was only 61%. Scans performed for persistent hypercalcemia 48 to 72 hours after reexploration in 2 patients were unsuccessful in demonstrating any residual parathyroid. Scans performed 3 months after surgery in the same 2 patients and a third patient were successful, with sensitivity and specificity of 100%. Apart from patient 11, who awaits reexploration, normocalcemia was eventually achieved in every patient, with 11 of 12 having an initial period of hypocalcemia.

CONCLUSIONS

Three months after reexploration and trimming or resection with transplant of half a gland left at first operation, sestamibi scanning achieved sensitivity and specificity of 100% in locating supernumerary parathyroids in patients with multiple endocrine neoplasia type 1 and persistent hypercalcemia. Before first reexploration, however, scans rarely provided new information, predominantly showing only the hypertrophied half-gland remnant.

A randomized controlled trial of phytoestrogen supplementation, growth and bone turnover in adolescent males

OBJECTIVE

To assess the effect of phytoestrogens on bone turnover and growth in adolescent boys.

DESIGN

Randomized double-blind placebo-controlled trial.

SETTING

Single school in northwest Tasmania.

PARTICIPANTS

Adolescent boys (treatment n=69, placebo n=59, mean age 16.8 y).

INTERVENTIONS

Six weeks of isoflavone supplementation (Novasoy, 50 mg daily of isoflavone equivalents). Bone turnover markers (bone specific alkaline phosphatase (BAP) and pyridinoline creatinine ratio (PYR)) were measured at baseline and follow-up.

RESULTS

Despite marked increases in urinary genistein and daidzein in the treatment arm (both P<0.001), there were no significant differences in BAP, PYR or short-term height or weight change. This applied to both intention-to-treat and per protocol analysis. Neither was there a significant correlation between urinary genistein and daidzein levels and BAP or PYR.

CONCLUSIONS

Phytoestrogen supplementation to the level of usual Japanese dietary intake has no measurable effect on bone turnover in adolescent boys. Longer-term studies of bone density may be desirable but it is unlikely that there will be a large effect in either girls or boys given the lower endogenous oestrogen levels in boys.

Somatotrophinomas in multiple endocrine neoplasia type 1: a review of clinical phenotype and insulin-like growth factor-1 levels in a large multiple endocrine neoplasia type 1 kindred

PURPOSE

Within the spectrum of pituitary disease in multiple endocrine neoplasia type 1 (MEN-1), widely disparate prevalence rates for somatotrophinomas have been described. Studies that combine multiple, small MEN-1 kindreds report pituitary disease in 60% to 65% of patients, somatotrophinomas accounting for 27% to 37% of total pituitary lesions. However, reports based on large MEN-1 family screening programs have produced lower prevalence rates for pituitary adenomas (9% to 40%), of which somatotrophinomas comprise up to 14%. We sought to determine the prevalence of both biochemical and clinically overt growth hormone (GH) hypersecretion in the largest reported MEN-1 genealogy, the Tasman 1 kindred.

PATIENTS AND METHODS

The Tasman 1 MEN-1 kindred contains 165 members with established MEN-1. We reviewed the records of 124 MEN-1 patients for evidence of acromegaly or gigantism. To determine if clinical criteria underestimate the occurrence of biochemical GH hypersecretion, a subset of 33 patients was assessed for elevated levels of serum insulin-like growth factor-1 (IGF-1).

RESULTS

No cases of acromegaly or gigantism were detected in the 124 patients reviewed. Of the 33 patients screened with IGF-1, 13 had previously diagnosed pituitary lesions--11 prolactinomas and 2 nonsecretory lesions. The IGF-1 levels were normal in all patients studied. There were no significant differences in mean IGF-1 values between patients with and without pituitary lesions.

CONCLUSIONS

This report represents the largest study of growth hormone secretion patterns thus far described in MEN-1. The apparent absence of somatotrophinomas in a kindred of this size is unexpected. These results support the existence of kindred-specific MEN-1 phenotypes. We conclude that the pathogenesis of GH-secreting adenomas in MEN-1 is influenced by secondary factors acting in synergy with the well-documented primary MEN-1 gene defect on chromosome 11q13.

Impairments in Adipose Tissue Microcirculation in Type 2 Diabetes Mellitus Assessed by Real-Time Contrast-Enhanced Ultrasound

BACKGROUND

In obesity and type 2 diabetes mellitus (T2D), adipose tissue expansion (because of larger adipocytes) results in reduced microvascular density which is thought to lead to adipocyte hypoxia, inflammation, and reduced nutrient delivery to the adipocyte. Adipose tissue microvascular responses in humans with T2D have not been extensively characterized. Furthermore, it has not been determined whether impaired microvascular responses in human adipose tissue are most closely associated with adiposity, inflammation, or altered metabolism.

METHODS AND RESULTS

Overnight-fasted healthy controls (n=24, 9 females/15 males) and people with T2D (n=21, 8 females/13 males) underwent a body composition scan (dual-energy X-ray absorptiometry), an oral glucose challenge (50 g glucose) and blood analysis of clinical chemistries and inflammatory markers. Abdominal subcutaneous adipose tissue microvascular responses were measured by contrast-enhanced ultrasound at baseline and 1-hour post-oral glucose challenge. Adipose tissue microvascular blood volume was significantly elevated in healthy subjects 1-hour post-oral glucose challenge; however, this effect was absent in T2D. Adipose tissue microvascular blood flow was lower in people with T2D at baseline and was significantly blunted post-oral glucose challenge compared with controls. Adipose tissue microvascular blood flow was negatively associated with truncal fat (%), glucoregulatory function, fasting triglyceride and nonesterified fatty acid levels, and positively associated with insulin sensitivity. Truncal fat (%), systolic blood pressure, and insulin sensitivity were the only correlates with microvascular blood volume. Systemic inflammation was not associated with adipose tissue microvascular responses.

CONCLUSIONS

Impaired microvascular function in adipose tissue during T2D is not conditionally linked to systemic inflammation but is associated with other characteristics of the metabolic syndrome (obesity, insulin resistance, hyperglycemia, and dyslipidemia).