C-peptide is a predictor of telomere shortening: A five-year longitudinal study.

Aim: Relative telomere length (RTL) predicts the development of many age-related diseases. Yet, few studies have evaluated their longitudinal effect on RTL. We investigated longitudinally the association between cardiometabolic risk factors and RTL. Methods: This was a longitudinal study with a 5-year follow-up period, based on data collected in 2014 and 2019. Of 478 participants in 2014, 198 consented to be followed-up in 2019. The associations between RTL and risk factors were analyzed using t-test, ANOVA or simple linear regression as applicable. Results: RTL was significantly shortened after 5 years (P<0.001). Older age (P=0.018) and gender (P=0.05) were significantly associated with shorter RTL at follow-up. Higher baseline C-peptide correlated with shorter RTL (P=0.04) and shortening of RTL (P=0.03) after 5 years. Multivariate linear regression including both age and gender revealed a significant trend for C-peptide and change in RTL after 5 years (P=0.04). Interestingly, there was a trend of shorter RTL at follow-up with diabetes, though the findings were not statistically significant. Conclusions: Higher C-peptide level contributes to telomere shortening over time, suggesting that metabolic dysregulation may play a role in early aging. Further understanding of this relationship and addressing high C-peptide levels can be important to prevent premature aging.

Incidence of diabetes and its predictors in the Greater Beirut Area: a five-year longitudinal study.

BACKGROUND: Type 2 Diabetes (T2D) remains a world epidemic. Obtaining accurate estimates of its incidence and their predictors will aid in targeting preventive measures, allocating resources, and strategizing its management. The Middle East North Africa region has high T2D prevalence and rates of rise. Few incidence studies exist for the region, and none from Lebanon. The current study objective was to determine diabetes incidence and diabetes predictors in a community-based Lebanese sample. A secondary objective was to describe the metabolic control over time in adults with preexisting diabetes. METHODS: This is a five-year (2014-2019) follow-up study on a random sample of 501 residents of the Greater Beirut area. Out of 478 people eligible to participate in the follow-up study, 198 returned (response rate 39.5%). Assessment included medical history, anthropometric measures, food frequency, sleep, and lifestyle questionnaires. Laboratory data included glycemic indices (fasting glucose and HbA1C) and other biological markers. The diagnosis of probable diabetes (PD) was based on one abnormal test for either fasting glucose ≥ 126 mg/dL or HbA1C ≥ 6.5% or having history of diabetes. RESULTS: The incidence of diabetes was 17.2 (95% CI 9.6-28.7) per 1000 person-years. Cardiometabolic risk factors independently associated with diabetes were: older age, higher BMI, family history of diabetes, metabolic syndrome, higher CRP and triglyceride level; whereas an independent predictor of diabetes was previous BMI. In addition, the 42 participants with preexisting diabetes had worsening of their metabolic profile over a five-year period. CONCLUSIONS: The incidence of diabetes was high as compared to some reported world rates, and in line with the high prevalence in the MENA region. The risk was highest in those with positive family history and the presence of the metabolic syndrome or its components. Preventive measures should particularly target participants with that specific risk profile. This becomes particularly important when observing that metabolic control gets worse over time in individuals with diabetes.

Vitamin D Deficiency in Lebanese Adults: Prevalence and Predictors from a Cross-Sectional Community-Based Study.

METHODS: A random sample of Lebanese adults residing in the Greater Beirut area was selected based on area probability and multistage cluster sampling. Data from 446 participants (68% females) with mean age 45.3 ± 15 years were used for the analyses. Participants were recruited between March and May. Serum 25-hydroxyvitamin D levels were measured using electrochemiluminescent immunoassay. RESULTS: Vitamin D deficiency was highly prevalent whether using the cutoff of 50 nmol/L or using the more conservative cutoff of 30 nmol/L; more specifically, 71.9% and 39.1% of the study population were deficient using the above cutoffs, respectively In the bivariate analyses, gender, BMI and body fat mass, socioeconomic factors (income and education level), alcohol consumption, dietary intake of fat and of vitamin D, serum LDL-cholesterol, and serum creatinine were all associated with vitamin D status. After adjustment for multiple covariates, age, income, alcohol consumption, and serum creatinine were independent predictors of vitamin D deficiency. CONCLUSION: Vitamin D deficiency is highly prevalent in Lebanon. Preventive measures should target the modifiable risk factors.

Pituitary incidentalomas in paediatric population: Incidence and characteristics.

OBJECTIVE: To determine the incidence of pituitary incidentalomas in the paediatric population and among its different age subgroups as well as to identify the characteristics of these lesions. Additionally, we aim to give a perspective on the management and follow-up of these patients. DESIGN AND PATIENTS: We retrospectively studied MRI of children aged 18 years or below who underwent MRI with sellar region within their field of view between January 2010 and December 2018. MEASUREMENTS: Pituitary lesions were considered incidental according to the definition by the Endocrine Society. We reported the size, location and signal characteristics of each lesion. Medical charts of the subjects were reviewed for age, sex, the MRI indication and the hormonal assays levels. RESULTS: We identified 40 pituitary lesions of which 31 were incidental lesions. The incidence of pituitary incidentaloma in our cohort was 22 per 1000 patients with female predisposition ( 64.5%) and a mean age of 11 ± 6 years. Rathke's cleft cyst was the most prevalent lesion, accounting for 67.7% followed by cystic pituitary lesions and microadenomas. The most common indications for imaging were growth disturbance (12.9%) followed by headache (9.7%). Abnormal laboratory workup was present in 13% of the subjects. Incidental lesions were more common in the older age groups compared to young children. CONCLUSION: Incidental pituitary lesions in the paediatric population are relatively infrequent and increases with age. Rathke's cleft cyst is the most common incidentally encountered pituitary lesion followed by cystic pituitary lesions and microadenomas.

Early Sialadenitis After Radioactive Iodine Therapy for Differentiated Thyroid Cancer: Prevalence and Predictors.

INTRODUCTION: Sialadenitis is a frequent occurrence after radioactive iodine therapy (RAI). However, reports on its predictors and risk factors in the Eastern Mediterranean Region (EMRO) are scarce. AIM: This study aimed to identify risk factors for early sialadenitis in patients receiving RAI for differentiated thyroid cancer (DTC) at the American University of Beirut Medical Center. It also aimed to determine the prevalence and characteristics of such patients receiving RAI at our institution. METHODS: This was a retrospective study conducted at the American University of Beirut Medical Center. Medical charts were reviewed for all patients 18-79 years of age admitted to receive RAI for DTC between 01/01/2012 and 31/12/2015. Sialadenitis was deemed present if there were any records of neck swelling/pain, dry mouth, or difficulty swallowing within 48 hours of RAI administration. Characteristics between patients with sialadenitis and those without were compared to determine predictors. RESULTS: There were 174 patients admitted to receive RAI, predominantly females (71.3%), with papillary thyroid cancer (93.1%). The majority had lymph node involvement (64.5%). Pretreatment thyroid stimulating hormone (TSH) was greater than 75 mIU/ml in most patients (72.6%). The prevalence of sialadenitis was 20.1% (95% CI (15-27)). Being non-Lebanese and having a positive whole-body scan were associated with sialadenitis and persisted after adjustments (OR = 2.34 and 3.99). Non-Lebanese patients had higher rates of lymph nodes involvement (p value 0.005) and were kept off levothyroxine for longer periods (p value 0.02). CONCLUSION: The prevalence of sialadenitis at our institution was similar to other reported studies from the world. However, risk factors allude to more iodine exposure in the neck with positive whole-body scan uptake, lymph node involvement, and prolonged period of hypothyroidism.

A healthy lifestyle pattern is associated with a metabolically healthy phenotype in overweight and obese adults: a cross-sectional study.

PURPOSE: This study tried at identifying lifestyle patterns in a sample of Lebanese adults and investigating their association with metabolically healthy overweight and obesity (MHOv/O). METHODS: This study used data from a community-based survey of Lebanese adults living in Greater Beirut (n = 305). Dietary intake was assessed using an 80-item food frequency questionnaire. MHOv/O was defined as having one or none of the following metabolic abnormalities: triglycerides ≥ 150 mg/dL; systolic blood pressure ≥ 130 mmHg; diastolic blood pressure ≥ 85 mmHg; fasting blood glucose ≥ 100 mg/dL; HDL-cholesterol < 40 mg/dL for men and < 50 mg/dL for women. 201 subjects were overweight/obese and 98 had MHOv/O. Factor analysis was implemented to derive lifestyle patterns. RESULTS: Two lifestyle patterns were identified: the unhealthy lifestyle pattern, which included foods such as fast food and soft drinks and was characterized by alcohol consumption and cigarette smoking. Eating at home loaded negatively on this pattern. The healthy lifestyle pattern was characterized by positive loadings of food groups such as milk and dairy products, fruits, vegetables and legumes. Sleep difficulties loaded negatively on this pattern, while vigorous and moderate physical activity loaded positively. Multiple logistic regression analyses showed that subjects belonging to the 3rd tertile of the healthy pattern scores had higher odds of MHOv/O as compared to those in the 1st tertile (OR 2.33, CI 1.04-4.81). CONCLUSIONS: Findings of this study provided evidence on the combined effect of lifestyle patterns in relation to cardiometabolic abnormalities and highlighted the importance of focusing on 'holistic' lifestyle pattern modifications in designing and implementing prevention interventions in overweight and obese subjects.

Characterization of metabolic changes in the phenotypes of women with polycystic ovary syndrome in a large Mediterranean population from Sicily.

OBJECTIVE: To better characterize the metabolic alterations in various phenotypes of polycystic ovary syndrome (PCOS) in a large homogeneous (Sicilian) Mediterranean population with a low prevalence of obesity. DESIGN: Retrospective study. PATIENTS: A total of 1215 consecutively evaluated women with PCOS divided into four Rotterdam phenotypes (A, B, C and D) and in 108 matched ovulatory, nonhyperandrogenic women. MEASUREMENTS: BMI, fasting glucose, total cholesterol, HDL cholesterol, triglycerides, LDL cholesterol and an oral glucose tolerance test. RESULTS: The overall prevalence of obesity was 31%, metabolic syndrome 6.6%, diabetes 2.1%, altered glucose metabolism 13.1%, and abnormal lipid profile 60%. Phenotype B had the highest prevalence of obesity, metabolic syndrome, altered glucose metabolism and lipid abnormalities compared to other PCOS phenotypes and controls. Phenotype A was more obese and more women had metabolic syndrome compared to phenotypes C and D but phenotype C had a similar prevalence of altered glucose metabolism and lipid abnormalities compared to phenotype A which had a higher BMI. These metabolic abnormalities in A and C were higher compared to phenotype D and controls. Multivariate analysis showed that BMI predicts only abnormalities in fasting glucose and triglycerides, while there was no association with androgens. CONCLUSIONS: In Mediterranean women with PCOS from Sicily with a lower prevalence of obesity, the prevalence of diabetes, altered glucose metabolism and metabolic syndrome were much lower than reported in US studies. Phenotype B was the most metabolically affected phenotype, followed by phenotype A. Phenotype C had an intermediate disorder but with a high prevalence of altered glucose metabolism and lipid alterations. Only the normoandrogenic phenotype D had no metabolic abnormalities.

Corrigendum to "Five-Year Incidence and Progression of Diabetic Retinopathy in Patients with Type II Diabetes in a Tertiary Care Center in Lebanon".

[This corrects the article DOI: 10.1155/2017/9805145.].

A minimally processed dietary pattern is associated with lower odds of metabolic syndrome among Lebanese adults.

OBJECTIVE: To (i) estimate the consumption of minimally processed, processed and ultra-processed foods in a sample of Lebanese adults; (ii) explore patterns of intakes of these food groups; and (iii) investigate the association of the derived patterns with cardiometabolic risk. DESIGN: Cross-sectional survey. Data collection included dietary assessment using an FFQ and biochemical, anthropometric and blood pressure measurements. Food items were categorized into twenty-five groups based on the NOVA food classification. The contribution of each food group to total energy intake (TEI) was estimated. Patterns of intakes of these food groups were examined using exploratory factor analysis. Multivariate logistic regression analysis was used to evaluate the associations of derived patterns with cardiometabolic risk factors. SETTING: Greater Beirut area, Lebanon. SUBJECTS: Adults ≥18 years (n 302) with no prior history of chronic diseases. RESULTS: Of TEI, 36·53 and 27·10 % were contributed by ultra-processed and minimally processed foods, respectively. Two dietary patterns were identified: the 'ultra-processed' and the 'minimally processed/processed'. The 'ultra-processed' consisted mainly of fast foods, snacks, meat, nuts, sweets and liquor, while the 'minimally processed/processed' consisted mostly of fruits, vegetables, legumes, breads, cheeses, sugar and fats. Participants in the highest quartile of the 'minimally processed/processed' pattern had significantly lower odds for metabolic syndrome (OR=0·18, 95 % CI 0·04, 0·77), hyperglycaemia (OR=0·25, 95 % CI 0·07, 0·98) and low HDL cholesterol (OR=0·17, 95 % CI 0·05, 0·60). CONCLUSIONS: The study findings may be used for the development of evidence-based interventions aimed at encouraging the consumption of minimally processed foods.

The Landscape of Glucose-Lowering Therapy and Cardiovascular Outcomes: From Barren Land to Metropolis.

The choice of glucose-lowering therapy (GLT) has expanded to include 11 different classes in addition to insulin. Since the 2008 Food and Drug Administration guidance for industry and mandate of demonstrating cardiovascular (CV) safety prior to any new drug approval, there were several trials primarily conducted to establish that goal. Some had neutral effects, while there were positively beneficial outcomes with more recent studies. Hospitalization for congestive heart failure has also been a heterogeneous finding among the different classes of GLT, with drug outcomes ranging from risky to beneficial. The current review selectively focuses on the evidence for CV outcomes for each class of GLT and summarizes the existing guidelines with regard to these drugs in heart disease. Moreover, it illustrates the dynamic status in the development of evidence. Finally, the review enables healthcare providers to formulate a plan for hypoglycemic therapy which will optimize CV health, in a patient-centered manner.

PREVALENCE OF DIABETES IN GREATER BEIRUT AREA: WORSENING OVER TIME.

OBJECTIVE: The Middle East North Africa region has one of the highest rates of diabetes, both in prevalence and in rate of increase. The aim of this study was to examine the prevalence and associated risk factors of type 2 diabetes mellitus (T2D) in the adult population of Beirut. METHODS: A random sample of 501 men and women aged 18 to 79 years was examined in a cross-sectional manner. The sample was then divided into 3 groups based on T2D self-report, glycosylated hemoglobin (HbA1c), and fasting glucose (no diabetes [ND], at risk for diabetes [RD], and probable diabetes [PD]). These were compared to determine the various associated risks. RESULTS: The sample consisted of 64.3% women, with an average age of 45.4 ± 15 years, and a mean body mass index (BMI) of 29.4 ± 5.9 kg/m2. The subjects were predominantly from a low socio-economic status, and more than half smoked either cigarettes or a waterpipe. The percentages of the 3 groups were as follows: 41.7%, 40.3%, and 18.0% for ND, RD, and PD, respectively. Out of 90 subjects diagnosed with PD, 26 did not know they had diabetes. Independent, positively associated risk factors were age, BMI, heart rate, hypertension, triglyceride, and high-density lipoprotein cholesterol. CONCLUSION: The prevalence of T2D was high in this study and seems to be increasing compared to prior diabetes reports. Overall, the whole sample had a high prevalence of cardiovascular risk factors such as smoking, obesity, and physical inactivity. However, subjects with diabetes had significantly more components of the metabolic syndrome. ABBREVIATIONS: ADA = American Diabetes Association CRP = C-reactive protein DD = definite diabetes FPG = fasting plasma glucose HbA1c = glycosylated hemoglobin MENA = Middle-East North Africa ND = no diabetes PD = probable diabetes RD = at risk of diabetes T2D = type 2 diabetes mellitus TSH = thyroid-stimulating hormone.

Five-Year Incidence and Progression of Diabetic Retinopathy in Patients with Type II Diabetes in a Tertiary Care Center in Lebanon.

OBJECTIVE: To estimate the 5-year incidence of progression rate and regression rate and risk factors for diabetic retinopathy (DR) in a cohort of Lebanese patients with type II diabetes. METHODS: We followed a cohort of 462 Lebanese patients with type II diabetes for over 5 years at the American University of Beirut Medical Center. Patients underwent yearly complete ophthalmic evaluation and fundus photographs and were assessed for the incidence, stage, and evolution of DR using modified Airlie House classification. RESULTS: Among the 462 patients, 281 had no DR at baseline. The 5-year cumulative incidence of any DR was 10% (95% CI: 6-13), and only baseline microalbuminuria correlated with the development of DR (OR = 10.53, 95% CI: 4.39-25.23, p < 0.0001). Among the 181 patients with baseline DR, the worsening and regression rates of DR were 31.5% (95% CI: 25-38) and 9% (95% CI: 5-13), respectively. Microalbuminuria also approached statistical significance as a risk factor for DR worsening (OR = 1.89, 95% CI: 0.97-3.70, p = 0.06). CONCLUSION: The 5-year incidence of DR in this hospital-based cohort is relatively low. Microalbuminuria was independently associated with the incidence and progression of the disease. We recommend to screen patients with type II diabetes for microalbuminuria as prognostic for the development and worsening of DR.

Comparison of quality of life in a group of Lebanese type 1 diabetics on insulin pump and those on multiple daily injections.

AIM: The aim of the study is to investigate the differences in the quality of life (QOL) in Lebanese youths with type 1 diabetes using continuous subcutaneous insulin infusion (CSII) and those using multiple daily injections (MDI) treatment modalities. METHODS: A descriptive, cross-sectional, comparative matched design was used. The sample included 36 adolescents and young adults on one of two treatment modalities (CSII or MDI) and matched for age, gender, and level of education. QOL was measured with the Indiana Diabetes Quality of Life for Youth and latest HbA1C level was recorded. RESULTS: The CSII group had significantly lower HbA1C levels (p < 0.001), and reported better health perception (p = 0.029), more satisfaction with life (p = 0.002), less impact of the disease (p = 0.002), and fewer worries about their disease (p = 0.029), compared to the MDI group. The overall quality of life score was also significantly better in the CSII group than in the MDI group (p = 0.001). CONCLUSIONS: Findings suggest that CSII is associated with better glycemic control and QOL in the Lebanese youth population with type 1 diabetes.

The prevalence of endocrinopathies among Lebanese women presenting with hirsutism to an endocrine clinic.

UNLABELLED: Hirsutism is a common condition in women characterized by excessive growth of terminal hair in a male pattern distribution. It may be a manifestation of underlying pathologies. Since there is no data published about the prevalence of endocrinopathies among hirsute women in Lebanon, this study's aim was to reveal the most common etiologies of hirsutism in this population. METHODS: The study is a descriptive review of cases of 160 females with hirsutism presenting to a single endocrinologist clinic. Data about history, physical exam, blood tests and imaging results were collected after review of medical charts. RESULTS: Out of the 160 cases reviewed, 14 females (8.8%) were left undiagnosed. Out of 146 subjects diagnosed, 72.6% were found to have polycystic ovary syndrome (PCOS), 18.5% idiopathic hirsutism (IH), 4.6% non-classic congenital adrenal hyperplasia, 2.6% hyperprolactinemia, 0.6% Cushing's syndrome and 0.6% hypothyroidism. A higher percentage of irregular menses and a trend for overweight were found among the PCOS group. CONCLUSIONS: PCOS remains the most common cause of hirsutism in an endocrine referral clinic, similar to other populations. A low threshold for diagnostic workup is in order, especially when there is associated menstrual irregularity or overweight.

Overview of the physiology and pathophysiology of leptin with special emphasis on its role in the kidney.

The adipocyte product leptin is a pleiotropic adipokine and hormone, with a role extending beyond appetite suppression and increased energy expenditure. This review summarizes the biology of the leptin system and the roles of its different receptors in a multitude of cellular functions in different organs, with special emphasis on the kidney. Leptin's physiological functions as well as deleterious effects in states of leptin deficiency or hyperleptinemia are emphasized. Chronic hyperleptinemia can increase blood pressure through the sympathetic nervous system and renal salt retention. The concept of selective leptin resistance in obesity is emerging, whereby leptin's effect on appetite and energy expenditure is blunted, with a concomitant increase in leptin's other effects as a result of the accompanying hyperleptinemia. The divergence in response likely is explained by different receptors and post-receptor activating mechanisms. Chronic kidney disease is a known cause of hyperleptinemia. There is an emerging view that the effect of hyperleptinemia on the kidney can contribute to the development and/or progression of chronic kidney disease in selective resistance states such as in obesity or type 2 diabetes mellitus. The mechanisms of renal injury are likely the result of exaggerated and undesirable hemodynamic influences as well as profibrotic effects.

Slipped capital femoral epiphysis in a patient with Turner syndrome receiving growth hormone therapy.

OBJECTIVE: To report a case of slipped capital femoral epiphysis in a young patient with Turner syndrome (TS) receiving growth hormone therapy and to emphasize the importance of keeping this orthopedic condition in mind during management of this patient group. METHODS: Clinical, laboratory, and radiographic findings are presented, and risk factors for slipped capital femoral epiphysis are discussed. RESULTS: A child with TS presented for medical assessment because of a limp but with no history of trauma or febrile illness. Growth hormone therapy had been administered for 1 year because of her short stature. Physical examination and pelvic radiography of the patient showed the presence of bilateral slipped capital femoral epiphysis. She underwent bilateral pinning in situ, and growth hormone therapy was terminated. At follow-up after more than 2 years, no sequelae were noted. CONCLUSION: Patients with TS are at high risk for developing certain orthopedic conditions, such as slipped capital femoral epiphysis. Furthermore, slipped capital femoral epiphysis is a known complication of growth hormone therapy in growing children. A limp, hip pain, knee pain, or thigh pain might be a symptom of slipped capital femoral epiphysis in patients with TS, especially those receiving growth hormone therapy. Prompt recognition and treatment of this condition are important for prevention of sequelae.

Orthopedic complications related to growth hormone therapy in a pediatric population.

Since the introduction of recombinant growth hormone, its use has diversified and multiplied. Growth hormone is now the recommended therapy for a growing indication to all forms of short stature because of its direct and indirect role on bone growth. Hereby, we discuss the orthopedic complications associated with growth hormone treatment in pediatric patients. These complications include carpal tunnel syndrome, Legg-Calve-Perthes' disease, scoliosis, and slipped capital femoral epiphysis. Their incidence rates recorded in several growth hormone therapy-related pharmacovigilance studies will be summarized in this study with focused discussion on their occurrence in the pediatric and adolescent age groups. The pathogenesis of these complications is also reviewed.

Prevalence and determinants of retinopathy in a cohort of Lebanese type II diabetic patients.

OBJECTIVE: Our aim was to determine the prevalence and the risk factors for diabetic retinopathy (DR) in a cohort of type II diabetic patients in Lebanon. DESIGN: Prospective observational cohort study. PARTICIPANTS: Five hundred consecutive patients with type II diabetes mellitus followed at the American University of Beirut Medical Center diabetes clinic were enrolled in the study. METHODS: All patients 18 years or older with diabetes mellitus who did not have gestational diabetes and who were able to complete the laboratory data and the retinal examination were invited to participate in the study; they were followed up for a period of 3 years. RESULTS: DR was present in 175 patients (35%), 130 (26%), and 45 (9%) having nonproliferative and proliferative DR, respectively. Clinically significant macular edema was present in 42 patients (8%). Microvascular and macrovascular diabetic complications, duration of disease, glycemic control, presence of hypertension (p < 0.003), systolic blood pressure (p = 0.04), and insulin use (p < 0.001) were individually significantly associated with a higher prevalence of DR on bivariate analysis. However, on multivariate regression analysis, only glycosylated hemoglobin >7% (odds ratio [OR] 2.81, 95% CI 1.06-7.43, p = 0.038), duration of diabetes (per 10 years, OR 9.0, 95% CI 4.0-20.0, p < 0.001), macroalbuminuria (OR 2.6, 95% CI 1.14-5.96 p = 0.023), and systolic blood pressure (per 10 mm Hg, OR 1.27, 95% CI 1.0-1.56, p = 0.037) were independent risk factors for DR. CONCLUSIONS: The elevated prevalence of DR in type II diabetic patients with high risk profiles calls for early medical intervention and education about DR and its identified controllable risk factors.

Rapid rise in serum thyrotropin concentrations after thyroidectomy or withdrawal of suppressive thyroxine therapy in preparation for radioactive iodine administration to patients with differentiated thyroid cancer.

Patients with differentiated thyroid cancer are often treated transiently with T(3) in preparation for radioactive iodine (RAI) therapy. We questioned the value of using T(3) transiently in patients requiring RAI therapy. Two groups of patients requiring RAI therapy were investigated. One group included patients studied immediately after thyroidectomy, whereas the other included those withdrawn from chronic suppressive T(4) therapy that followed thyroidectomy and postoperative RAI ablation. Serum TSH concentrations were serially measured two to three times weekly until they reached more than 30 mU/liter, after which RAI therapy was administered. Serum TSH concentrations reached more than 30 mU/liter 8-26 d (mean +/- sd, 14.2 +/- 4.8) after thyroidectomy or 9-29 (18.1 +/- 4.1) d after T(4) withdrawal. That level of TSH elevation was achieved 18 d after thyroidectomy and 22 d after T(4) withdrawal in more than 95% of patients. Minimal symptoms of hypothyroidism were noted in either group when RAI was administered. Serum TSH concentrations increased rapidly without transient therapy with T(3). To minimize symptoms of hypothyroidism, serum TSH levels should be measured twice weekly, starting 10 d after thyroidectomy or T(4) withdrawal. The data cast doubt about the value and benefits from using T(3) in preparing patients for RAI therapy.

The value of dehydroepiandrosterone sulfate measurements in the assessment of adrenal function.

Dehydroepiandrosterone (DHEA) and its sulfated ester (DHEA-S) are corticotropin-dependent adrenal androgen precursors that are uniformly low in treated patients with corticotropin deficiency. There are no data investigating the diagnostic value of DHEA-S measurements in the prospective assessment of adrenal function. This study examined serum DHEA-S levels as possible markers for hypothalamic- pituitary-adrenal (HPA) function in patients with large pituitary adenomas. Patients were characterized to have normal HPA (n = 47) or abnormal HPA (ABN-HPA, n = 35) function based on their respective responses to insulin-induced hypoglycemia. Patients also underwent low-dose Cortrosyn (1 micro g, LDC) and standard-dose Cortrosyn stimulation testing. All patients with ABN-HPA had very low age- and gender-matched serum DHEA-S levels. When the normal response to LDC was set at a cortisol level of at least 18.1 micro g/dl, 10 of 31 patients with ABN-HPA exhibited normal responses. Receiver operating characteristic curves for baseline DHEA-S and for maximal cortisol responses to LDC had areas of 0.984 (confidence interval, 0.962-1.000) and 0.893 (confidence interval, 0.817-0.969), respectively. LDC- or SDC-stimulated serum cortisol levels have significant limitations in defining HPA function. A normal age- and gender-specific serum DHEA-S level makes the diagnosis of corticotropin deficiency extremely unlikely. However, when serum DHEA-S levels are low, further testing is necessary to define HPA function.