Increased Dosage of MRA Improves BP and Urinary Albumin Excretion in Primary Aldosteronism With Suppressed Plasma Renin.

PURPOSE: Excessive aldosterone secretion causes a high risk of cardio-cerebrovascular events. Mineralocorticoid receptor antagonist (MRA) is 1 of the treatment strategies for primary aldosteronism (PA). However, current MRA treatment is insufficient because MRA-treated patients with suppressed plasma renin activity (PRA) < 1 ng/mL/h still had a higher risk of cardiovascular disease than those with unsuppressed PRA. This is a prospective interventional study to determine the effects of an increase in MRA dosage on blood pressure (BP) control and urinary albumin excretion (UAE) in MRA-treated PA patients. METHODS: Thirty-four PA patients were recruited, and 24 patients (6 male, 18 female) completed this study. Serum potassium concentration was assessed every two months to adjust the dosage of MRA safely for 6 months. The primary outcomes were the changes in BP and UAE between baseline and 6 months. RESULTS: Systolic BP (SBP) and log10UAE decreased significantly as the daily dose of MRA increased. Diastolic BP (DBP) tended to decrease. We divided the PA patients into two groups (baseline PRA < 1 ng/mL/h and baseline PRA ≥ 1 ng/mL/h) according to PRA. In the group with baseline PRA < 1 ng/mL/h but not that with baseline PRA ≥ 1 ng/mL/h, SBP, DBP and log10UAE after 6 months were significantly lower than those at baseline. CONCLUSIONS: The increase in MRA dosage improved BP and UAE in PA patients with suppressed PRA.

Relationships between time in range, glycemic variability including hypoglycemia and types of diabetes therapy in Japanese patients with type 2 diabetes mellitus: Hyogo Diabetes Hypoglycemia Cognition Complications study.

AIMS/INTRODUCTION: Continuous glucose monitoring (CGM) metrics, such as times in range (TIR) and time below range, have been shown to be useful as clinical targets that complement glycated hemoglobin (HbA1c) for patients with type 2 diabetes mellitus. We investigated the relationships between TIR, glycemic variability and patient characteristics in patients with type 2 diabetes mellitus. MATERIALS AND METHODS: We carried out continuous glucose monitoring in 281 outpatients with type 2 diabetes mellitus who participated in a multicenter cohort (Hyogo Diabetes Hypoglycemia Cognition Complications) study. RESULTS: The results are shown as the median (interquartile range). The age, disease duration and HbA1c were 68 years (62-71 years), 13 years (7-23 years) and 6.9% (6.5-7.5%), respectively. TIR and standard deviation obtained by continuous glucose monitoring worsened significantly with increasing disease duration. Multiple regression analyses showed that disease duration (standard partial regression coefficient, ß = -0.160, P = 0.003), diabetic peripheral neuropathy (ß = -0.106, P = 0.033) and urinary albumin excretion (ß = -0.100, P = 0.043) were useful explanatory factors for TIR. In contrast, HbA1c (ß = -0.398, P < 0.001) and the use of antidiabetic drugs potentially associated with severe hypoglycemia (ß = 0.180, P = 0.028), such as sulfonylureas, glinides and insulin, were useful explanatory factors for time below range in the elderly patients with type 2 diabetes mellitus. CONCLUSIONS: The results of this study suggest that disease duration and diabetic complications are associated with TIR deterioration. In addition, low HbA1c levels and the use of antidiabetic drugs potentially associated with severe hypoglycemia might worsen the time below range in the elderly.

Diabetes Mellitus Itself Increases Cardio-Cerebrovascular Risk and Renal Complications in Primary Aldosteronism.

CONTEXT: The prevalence of diabetes mellitus (DM) in patients with primary aldosteronism (PA) is higher than in those with essential hypertension and the general population. Although DM is a common major risk factor for cardio-cerebrovascular (CCV) diseases and renal complications, details of its effects in PA have not been demonstrated. OBJECTIVE: The aim of this study was to determine the effects of coexistent DM on the risk of CCV events and progression of renal complications in PA patients. DESIGN: A multi-institutional, cross-sectional study was conducted. PATIENTS AND METHODS: PA patients experienced between January 2006 and October 2016 and with available data of CCV events and DM were enrolled from the Japan PA registry of the Japan Primary Aldosteronism Study/Japan Rare Intractable Adrenal Diseases Study (n = 2524). CCV events and renal complications were compared between a DM group and a non-DM group by logistic and liner-regression analysis. RESULTS: DM significantly increased the odds ratio (OR) of CCV events (OR 1.59, 95% CI: 1.05-2.41) and that of proteinuria (OR 2.25, 95% CI: 1.59-3.16). DM correlated significantly with declines in estimated glomerular filtration rate (ß = .05, P = .02). CONCLUSIONS: This the first report to demonstrate the presence of DM as an independent risk factor for CCV events and renal complications, even in PA patients. Management of DM should be considered in addition to the specific treatment of PA.

Glucocorticoid Replacement Affects Serum Adiponectin Levels and HDL-C in Patients With Secondary Adrenal Insufficiency.

CONTEXT: Low serum adiponectin and high-density lipoprotein-cholesterol (HDL-C) levels are risk factors for cardiovascular disease. Patients with primary adrenal insufficiency are at higher risk of cardiovascular complications compared with healthy subjects. However, there is no information on the relationship between adiponectin and glucocorticoid replacement therapy in patients with secondary adrenal insufficiency (SAI). OBJECTIVE: To determine the effects of intrinsic adrenal function and glucocorticoid replacement therapy on serum adiponectin levels and lipid profile in patients with SAI. DESIGN: Part 1: a cross-sectional study. Part 2: a randomized, double-blind, crossover study. SETTING: Osaka University Hospital, Osaka, Japan. PATIENTS: Part 1: 58 patients diagnosed with nonfunctioning pituitary adenoma who underwent insulin tolerance test (ITT) for assessment of adrenal function. Part 2: 12 SAI patients randomly received hydrocortisone replacement therapy at a dose of 10, 20, or 30 mg/d for 4 weeks per term for three terms. OUTCOME MEASUREMENTS: Part 1: we analyzed the relationship between serum cortisol levels during ITT and serum adiponectin levels and the lipid profile. Part 2: serum adiponectin levels and lipid profile were measured every 4 weeks. RESULTS: Serum levels of adiponectin and HDL-C correlated significantly with peak cortisol levels after ITT. Serum adiponectin and HDL-C levels were significantly lower in patients with SAI than non-SAI. Serum levels of adiponectin and HDL-C increased in a hydrocortisone dose-dependent manner. CONCLUSIONS: Glucocorticoid replacement therapy increased serum levels of adiponectin, an adipose-derived anti-atherogenic factor, and HDL-C in patients with SAI.

The number of positive confirmatory tests is associated with the clinical presentation and incidence of cardiovascular and cerebrovascular events in primary aldosteronism.

Primary aldosteronism (PA) is a major cause of secondary hypertension and presents a higher risk for cardio-cerebrovascular (CCV) events compared with essential hypertension. To diagnose PA after a positive screening test, at least one of three available confirmatory tests [the saline infusion test (SIT), the captopril challenge test (CCT) or the furosemide upright test (FUT)] should be performed. The aim of our study was to investigate the relationship between the number of positive confirmatory tests using SIT and CCT and the clinical presentation and prevalence of CCV events in 398 PA patients. The number of PA patients doubled when PA diagnosis was defined by positive results on either the SIT or CCT confirmatory tests (single positive) compared to positive results on both the SIT and CCT confirmatory tests (double positive). We also found a more typical clinical presentation of PA, such as the use of more antihypertensive drugs to control blood pressure and a higher incidence of hypokalemia, in PA patients with double positive confirmatory tests than in those with a single positive confirmatory test. The incidence of CCV events in PA patients with double positive confirmatory tests was significantly higher than that in those with a single positive confirmatory test. Our results demonstrated that the number of PA patients was doubled by the use of PA diagnostic criteria using a single positive confirmatory test compared to the use of double positive confirmatory tests. PA patients with double positive confirmatory tests were associated with a more typical clinical presentation and a higher incidence of CCV events than those with a single positive confirmatory test.

Clinical Characteristics of Acromegalic Patients With Paradoxical GH Response to Oral Glucose Load.

CONTEXT: A paradoxical GH response to oral glucose (OG) is often found in acromegaly. However, the clinical characteristics of patients with acromegaly and a paradoxical GH response to OG (OG responders) remain unclear. OBJECTIVE: The aim of the present study was to define the clinical characteristics of OG responders with acromegaly. DESIGN: Retrospective study. SETTING: Hospitalized care at Osaka University Hospital. PATIENTS AND METHODS: Of 63 patients with acromegaly admitted to our hospital from January 2006 to January 2017, 19 were classified as OG responders and 44 as nonresponders. The clinical characteristics of these groups were compared. RESULTS: Before surgery, OG responders had substantially greater IGF-1 SD scores than nonresponders (P < 0.05), although no difference was found in basal GH levels between the two groups (P = 0.46). Regarding glucose metabolism, 120-minute plasma glucose and immunoreactive insulin after OG administration and hemoglobin A1c were significantly greater in OG responders than in nonresponders (P < 0.01, P < 0.05, P < 0.05, respectively). GH levels during octreotide or bromocriptine testing were decreased more significantly in OG responders than in nonresponders (P < 0.05, P < 0.05, respectively). The proportion of pituitary tumors with hypointensity on T2-weighted MRI was significantly greater in OG responders than in nonresponders (P < 0.05). The difference in IGF-1 and parameters of glucose metabolism described disappeared between the two groups after surgery. CONCLUSIONS: The paradoxical GH response reflected the clinical characteristics, especially IGF-I level, glucose metabolism, and drug efficacy in acromegaly. A paradoxical GH response, in addition to the nadir GH levels, to OG load is potentially useful for evaluation of the clinical characteristics of acromegaly.

Evaluation of Hypothalamic-Pituitary-Adrenal Axis by the GHRP2 Test: Comparison With the Insulin Tolerance Test.

CONTEXT: GH-releasing peptide 2 (GHRP2) stimulates the hypothalamic-pituitary-adrenal axis (HPA) through the GH secretagogue receptor (GHSR) in the hypothalamus, in which ghrelin is a natural ligand. Therefore, the GHRP2 test (GHRP2T) could be used instead of the insulin tolerance test (ITT). OBJECTIVE: Can the GHRP2T replace the ITT for evaluation of HPA? DESIGN: The present retrospective study analyzed the clinical features and laboratory data from 254 patients admitted for evaluation of hypopituitarism who underwent both GHRP2T and ITT. We analyzed the association between the maximum cortisol level (Fmax) during both tests. Adrenocortical insufficiency was diagnosed by ITT. The suitability of GHRP2T was examined using the receiver operating characteristic curve. RESULTS: A strong correlation was found between Fmax measured using both tests (r = 0.777, P < 0.0001). However, the sensitivity (64%) and specificity (79%) showed that the GHRP2T was not suitable for clinical use. Various factors influenced the correlation, probably through their effects on ghrelin and/or GHSR, including functional adenoma (P < 0.05) and sex (P < 0.05). No substantial correlation was found between Fmax measured using both tests in patients with prolactinoma (n = 30). The exclusion of patients with functional adenoma revealed no factors that affected the association in male patients; however, age and menstruation significantly influenced it in female patients (P < 0.05). Analysis of the data from male subjects without functional adenoma (n = 104) showed high sensitivity (95%) and specificity (85%) for the GHRP2T. CONCLUSION: ITT can be substituted with GHRP2T for assessment of HPA in male patients free of functional adenoma.

TSH ratio as a novel diagnostic method for Cushing's syndrome.

Circadian variations impact thyrotropin (TSH) secretion; in Cushing's syndrome (CS) patients, the nocturnal serum TSH surge is abolished. The aim of this prospective study is to examine whether serum TSH surge may be a useful diagnostic method for CS. This prospective study recruited 136 inpatients for differential diagnosis of CS or subclinical CS (SCS), and 21 inpatients with depression at Osaka University Hospital. Serum TSH surge was assessed by the midnight-to-morning serum TSH ratio (2300-2400 h to 0800-0900 h). The diagnostic accuracy (sensitivity and specificity) between TSH ratio and ordinary screening tests [low-dose dexamethasone suppression test (LDDST), late-night serum cortisol and urine free cortisol (UFC)] were compared. Twenty-two patients were diagnosed as CS (12 overt CS and 10 SCS) and the remaining 120 patients were excluded for CS. The diagnostic accuracy of TSH ratio (cutoff value 1.0) yielded sensitivity 90.9% [95% confidence interval (CI) 70.8-98.9], specificity 95.0% (95% CI 89.4-98.1), and a high positive and low negative likelihood ratio [18.2 (95% CI 8.2-40.1) and 0.096 (95% CI 0.026-0.359), respectively]. The specificity of TSH ratio was significantly higher than LDDST and midnight serum cortisol test. The sensitivity of TSH ratio was significantly higher than UFC. TSH ratio showed more than 1.0 in all patients with depression and CYP3A4 inducer users. TSH ratio is a novel supportive diagnostic method with higher specificity than the current diagnostic methods for CS.

Saline Infusion Test highly associated with the incidence of cardio- and cerebrovascular events in primary aldosteronism.

Primary aldosteronism (PA) is caused by excess secretion of aldosterone and is an independent risk factor for cardio-cerebro-vascular (CCV) events. The goal of treatment of PA should include prevention of CCV events. A definitive diagnosis of PA is established by confirmatory tests [saline infusion test (SIT), furosemide upright test (FUT) and captopril challenge test (CCT)]. However, there is no information on whether the hormone levels measured by these confirmatory tests are associated with CCV events. The aim of this retrospective study was to elucidate the relationship between the results of the above confirmatory tests and prevalence of CCV disease in patients with PA. The study subjects were 292 PA patients who were assessed for past history of CCV events at the time of diagnosis of PA. CCV events were significantly higher in patients with positive than negative SIT (12.8% vs. 3.3%, p=0.04). There were no differences in the incidences of CCV events between patients with positive and negative CCT and FUT (CCT: 11.0% vs. 3.9%, p=0.13, FUT: 6.1% vs. 5.7%, p=0.93). Our results demonstrated a higher incidence of CCV disease in PA SIT-positive patients compared to those with negative test. SIT is a potentially useful test not only for the diagnosis of PA but also assessment of the risk of CCV events.

Plasma aldosterone level within the normal range is less associated with cardiovascular and cerebrovascular risk in primary aldosteronism.

BACKGROUND: Previous studies showed higher risk of cardiovascular and cerebrovascular (CCV) events in primary aldosteronism compared with essential hypertension, but the patients of these studies were limited to primary aldosteronism patients with high plasma aldosterone concentration (PAC). The introduction of the aldosterone-renin ratio as the screening test for primary aldosteronism led to the recognition of primary aldosteronism patients with normal PAC (nPA). However, there is no information on the risk of primary aldosteronism including nPA. METHOD: In this retrospectively and cross-sectional study, the clinical features and CCV event risk of primary aldosteronism at diagnosis including nPA were investigated and compared with essential hypertension. The study included 292 consecutive primary aldosteronism patients and 498 essential hypertension outpatients. All primary aldosteronism patients were diagnosed by autonomous aldosterone secretion using confirmatory tests, and then divided into nPA (n = 130) and primary aldosteronism patients with high PAC (hPA: n = 162) using a PAC cutoff level of less than 443 pmol/l (16 ng/dl), representing the normal upper limit of PAC. RESULTS: nPA patients were significantly older at diagnosis of primary aldosteronism and at onset of hypertension compared with hPA patients. They had milder hypokalemia and easier-to-control blood pressure. The results suggested that nPA could be considered a mild type of primary aldosteronism but not an early-stage hPA. Moreover, the risk of all CCV events in nPA was significantly lower than that in hPA (odds ratio 0.42, 95% confidence interval 0.18-0.90, P < 0.05) and not significantly higher than that in essential hypertension (odds ratio 0.95, 95% confidence interval 0.43-1.94, P = 0.899). CONCLUSION: This study suggests that aggressive diagnostic workout for nPA is less effective to prevent CCV events.

Relationship of each anterior pituitary hormone deficiency to the size of non-functioning pituitary adenoma in the hospitalized patients.

Non-functioning pituitary adenoma (NFPA) is often associated with hypopituitarism. Diagnosis of hypopituitarism is important because of its poor prognosis and low quality of life. Among hypopituitarism, it is difficult to diagnose secondary adrenocortical insufficiency and GH deficiency without hormone stimulation test. Therefore, the aim of our study was to identify patients with NFPA who require more careful endocrinological examination. We examined the relationship between NFPA size and the prevalence of each hypopituitarism or the response of each anterior pituitary hormone by insulin tolerance test, LHRH test and TRH test. We studied 63 patients with NFPA admitted for evaluation of pituitary function and surgical indication. They were classified three groups by tumor diameter. The prevalence of GH deficiency, male secondary hypogonadism, secondary hypothyroidism and PRL deficiency were higher in the group of larger tumor diameter (p<0.0001, p<0.05, p<0.05 and p<0.05, respectively). However, that of secondary adrenocortical insufficiency only tended to be higher (p=0.07). In the group with small NFPA (less than 20 mm), the prevalence of secondary adrenocortical insufficiency was 38% although those of GH deficiency, male secondary hypogonadism, secondary hypothyroidism and PRL deficiency were 0%, 0% and 8% and 9%, respectively. Anterior pituitary hormone responses except TSH had significantly negative correlation with tumor diameter (ACTH: r=-0.40, GH: r=-0.57, LH: r=-0.69, FSH: r=-0.46, PRL: r=-0.36). The results suggested physicians should proactively suspect GH deficiency, male secondary hypogonadism and secondary hypothyroidism in patients with larger NFPA. On the other hand, adrenocortical function should be examined even in patients with small NFPA.

Incompatibility between fasting and postprandial plasma glucose in patients with Cushing's syndrome.

It is shown that glucocorticoids have discordant effects on plasma glucose concentration through their effects on hepatic glycogen deposition, gluconeogenesis and peripheral insulin resistance. Cushing's syndrome caused by cortisol overproduction is frequently accompanied with diabetes mellitus, but fasting plasma glucose (FPG) and post-glucose load plasma glucose levels are not examined in patients with Cushing's syndrome. The aim of this study was to investigate FPG, HbA1c and oral glucose tolerance test (OGTT) 2-h PG and their relationship in patients with Cushing's syndrome, in comparison with control subjects. Sixteen patients with Cushing's syndrome (ACTH-dependent 31%, ACTH-independent 69% and diabetes mellitus 50%) and 64 controls (32 patients with type 2 diabetes mellitus and 32 non-diabetic subjects matched for age, sex and BMI) were enrolled in this study. HbA1c and FPG in the patients with Cushing's syndrome were not different from the controls, whereas the FPG/HbA1c ratio was significantly lower in the patients with Cushing's syndrome than the controls. OGTT 2-h PG was significantly higher in the non-diabetic patients with Cushing's syndrome than the non-diabetic controls, while HbA1c was not different between both groups and FPG was significantly lower in the patients with Cushing's syndrome than the controls. HOMA-ß but not HOMA-R was significantly higher in the patients with Cushing's syndrome than the controls. In conclusion, FPG was rather lower in the patients with Cushing's syndrome than the controls. Postprandial PG or post-glucose loaded PG, but not FPG, is useful to evaluate the abnormality of glucose metabolism in patients with Cushing's syndrome.

Clinical significance of screening for subclinical Cushing's disease in patients with pituitary tumors.

Cushing's syndrome (CS) is a clinical state caused by chronic excess of glucocorticoid, and results in hypertension, impaired glucose tolerance, and dyslipidemia. Recently, a mild state of pituitary CS without typical Cushingoid appearance (subclinical Cushing's disease; SCD) has been identified. However, the true prevalence of SCD and its effect on metabolic disorders remain obscure. The aim of this prospective study was to determine the prevalence of SCD according to the guideline proposed by the working group of the Japanese Ministry of Health, Welfare and Labor, and to assess the outcome of surgery on metabolic disorders. The prevalence of SCD was investigated in 105 consecutive patients diagnosed with pituitary adenomas by MRI. ACTH-dependent hypercortisolism was diagnosed based on the results of the 0.5 mg dexamethasone suppression test (serum cortisol >3.0 µg/dL) plus one positive finding of the following two tests: midnight serum cortisol level >5.0 µg/dL or ACTH increase >50% after 1-deamino-5-D-arginine vasopressin (DDAVP) challenge. The final diagnosis of SCD was established by positive staining for ACTH in surgically-excised pituitary adenoma. Three patients (4.8%) were diagnosed with SCD among 62 patients with pituitary adenoma. Transsphenoidal adenomectomy partially resulted in improvement of blood pressure and glucose metabolism in SCD patients. Our results emphasize the importance of SCD screening in patients with pituitary tumors, especially in those patients with metabolic disorders.

Postoperative changes in bone metabolism and bone mineral density in Japanese patients with acromegaly: a 3-year prospective study.

Growth hormone and insulin-like growth factor-I play important roles in regulating bone metabolism and bone mineral density in adulthood. However, the effect of excess growth hormone on bone metabolism and bone mineral density is not fully understood. Here, we investigated the long-term changes in bone metabolism and bone mineral density after a rapid decline in growth hormone levels due to transsphenoidal surgery in acromegalic patients. Eighteen acromegalic patients (10 males and 8 females) who underwent transsphenoidal surgery were enrolled in this prospective study. Bone formation marker (serum bone alkaline phosphatase), bone resorption marker (urinary type I collagen cross-linked N-telopeptide), and bone mineral density were measured before surgery and at 3 months, 1 year, and 3 years after transsphenoidal surgery. While both serum bone alkaline phosphatase and urinary type I collagen cross-linked N-telopeptide levels decreased significantly after surgery, serum bone alkaline phosphatase/urinary type I collagen cross-linked N-telopeptide ratio was significantly increased at 3 months and 3 years after surgery. Bone mineral density did not change markedly after surgery. In conclusion, the rapid decline in growth hormone levels following transsphenoidal surgery had no marked effect on bone mineral density for up to 3 years, despite significant changes in levels of bone turnover makers post-surgery.

Clinical significance of fluctuations in thyroid hormones after surgery for Cushing's syndrome.

Patients with Cushing's syndrome (CS) frequently develop hyperthyroidism after surgery due to SITSH (syndrome of inappropriate secretion of TSH) and this SITSH contributed to the symptoms of steroid withdrawal syndrome (SWS). However, the duration of fluctuations in thyroid hormones after surgery for CS remains unknown. The aim of this prospective study was to investigate the clinical course of fluctuation in thyroid hormone level in CS patients after surgery. Thyroid hormone levels [free T3 (FT3), free T4 (FT4) and TSH] and serum cortisol levels were measured before and 1, 3, 6 and 12 months after surgery in 8 patients with active CS (3 pituitary CS and 5 adrenal CS). FT3 levels were above the normal range in 75% of patients up to 6 months after surgery, but returned to the normal range by 12 months. However, TSH levels were not suppressed below the normal range throughout the first 12 months after surgery. Serious symptoms of SWS appeared during the 6-month period after surgery, but disappeared with normalization of thyroid function at 12 months, which was not related to the recovery of function hypothalamus-pituitary-adrenal axis after CS surgery. Therefore, T3 toxicosis could result in deterioration of SWS after surgery for CS. These results indicate that physicians need to take T3 toxicosis into consideration in the pathological evaluation of SWS within 12 months after surgery for CS.

Occurrence of thyroxine tablet (Thyradin S(®)) - induced liver dysfunction in a patient with subclinical hypothyroidism.

A 54-year-old woman with subclinical hypothyroidism developed liver dysfunction after increasing dose of levothyroxine (L-T4) in tablet form (Thyradin S(®)) from 25µg to 50µg. Viral hepatitis, autoimmune hepatitis and NASH were ruled out with examinations. After cessation of levothyroxine in 50µg tablet form, liver enzymes gradually returned to normal. She was diagnosed levothyroxine-induced liver injury, based on criteria proposed in DDW-J 2004 workshop. Thyradin S(®) powder 0.01% (here in after referred to as L-T4 in powder form) was tried as an alternative, and liver enzymes have remained within normal range. As for Thyradin S(®) tablet, additives are different for each type of levothyroxine sodium content. The difference of additive is whether Fe2O3 is contained or not: it is not included in Thyradin S(®) 50µg tablet and powder form. Although there are two case reports in the Japanese literature and three case reports in the English literature of liver dysfunction suspected due to L-T4, we cannot find past reports about cases of drug induced liver dysfunction due to Fe2O3 free levothyroxine tablet form. This is a rare case report of drug induced liver injury due to Fe2O3 free levothyroxine tablet form, and administration of L-T4 in powder form may be useful for treatment of cases similar to this one.

Effects of growth hormone excess on glycated albumin concentrations: Analysis in acromegalic patients.

BACKGROUND: Glycated albumin (GA) does not reflect glycemic control in patients with disorders of albumin metabolism. In the present study, we examined GA concentrations in acromegalic patients with growth hormone (GH) excess. METHODS: We studied the hormonal status of 29 acromegalic patients (10 patients had diabetes mellitus and the remaining 19 patients were non-diabetic), 20 patients with type 2 diabetes mellitus and 38 non-diabetic subjects matched for age, sex and body mass index. RESULTS: Serum GA concentrations, but not those of fasting plasma glucose, 2-h post-load plasma glucose and HbA1c, were significantly higher in non-diabetic acromegalic patients compared with non-diabetic control subjects. Serum GA concentrations, but not those of fasting plasma glucose and HbA1c, were significantly higher in diabetic acromegalic patients compared with patients with type 2 diabetes mellitus. CONCLUSIONS: This is the first report describing higher GA concentrations in acromegalic patients relative to plasma glucose concentrations. Special care should be taken when evaluating glycemic control using GA because acromegaly is frequently complicated with diabetes mellitus.

Serum albumin-adjusted glycated albumin is an adequate indicator of glycemic control in patients with Cushing's syndrome.

OBJECTIVES: We recently reported that glycated albumin (GA) in patients with Cushing's syndrome is low. In the present study, we examined whether serum albumin (SA)-adjusted GA (SAaGA) is an adequate indicator of glycemic control in patients with Cushing's syndrome. DESIGN AND METHODS: We studied 26 patients with Cushing's syndrome (13 patients without diabetes and 13 patients with diabetes). Twenty six non-diabetic subjects and 26 patients with type 2 diabetes mellitus matched for age, sex and BMI were used as the controls. SAaGA was calculated using the regression formula between SA and GA in non-diabetic patients with Cushing's syndrome and non-diabetic subjects. RESULTS: SA showed a significant correlation with GA in non-diabetic patients with Cushing's syndrome and non-diabetic subjects. GA, but not SAaGA, in non-diabetic patients with Cushing's syndrome was significantly lower than that in the non-diabetic controls. Furthermore, the GA/HbA1c ratio, but not the SAaGA/HbA1c ratio, in diabetic patients with Cushing's syndrome was significantly lower than that in the diabetic controls. The measured GA in the patients with Cushing's syndrome was significantly lower than the estimated GA, but there was no difference between SAaGA and the estimated GA. CONCLUSIONS: The present findings suggest that SAaGA is an adequate indicator of the glycemic control in patients with Cushing's syndrome.

Rapid decline in bone turnover markers but not bone mineral density in acromegalic patients after transsphenoidal surgery.

Growth hormone (GH) and insulin-like growth factor-I (IGF-I) play important roles in maintaining bone metabolism and bone mineral density (BMD) in adulthood, in addition to stimulating longitudinal bone growth in childhood. However, information on the effect of GH excess on bone metabolism and BMD is incomplete and requires further analysis. The aim of this study is to clarify the effect of rapid decline in GH levels after transsphenoidal surgery (TSS) on bone metabolism in acromegalic patients. In this prospective study, 22 patients (11 males and 11 females) with active acromegaly underwent TSS. Bone formation marker (serum bone alkaline phosphatase: BAP), bone resorption marker (urinary type I collagen cross-linked N-telopeptide: urinary NTx) and BMD were measured before and at 3 and 12 months after TSS. BAP was significantly decreased at 12 months after TSS, but not at 3 months. Urinary NTx was significantly decreased at 3 and 12 months after TSS. BMD did not change after TSS. In conclusion, the rapid fall in GH level after TSS had no effect on BMD for up to 12 months after TSS despite the decrease in markers of bone formation and resorption.