The effects of cannabis and cannabinoids on the endocrine system

With the increase in cannabis use due to policy changes and areas of decriminalization, it is important to recognize the potential impact of these substances on endocrine processes. Cannabinoids have many effects by activating the endocannabinoid system. This system plays a role in the normal functioning of nearly every organ and consists of the body's natural endocannabinoids, the cannabinoid receptors, and the enzymes and processes that regulate endocannabinoids. Exogenous cannabinoids such as Δ9-tetrahydrocannabinol (THC) are known to act through cannabinoid type 1 and 2 receptors, and have been shown to mimic endocannabinoid signaling and affect receptor expression. This review summarizes the known impacts of cannabis on thyroid, adrenal, and gonadal function in addition to glucose control, lipids, and bone metabolism, including: reduced female fertility, increased risk of adverse pregnancy outcomes, reduced sperm counts and function, lower thyroid hormone levels with acute use, blunting of stress response with chronic use, increased risk of prediabetes but lower risk of diabetes, suggested improvement of high density lipoproteins and triglycerides, and modest increase in fracture risk. The known properties of endocannabinoids, animal data, population data, and the possible benefits and concerns of cannabinoid use on hormonal function are discussed. The interconnectivity of the endocrine and endocannabinoid systems suggests opportunities for future therapeutic modalities which are an area of active investigation.

SARS-CoV-2 (COVID-19) and the Endocrine System

As SARS-CoV-2 (COVID-19) overtakes the world, causing moderate to severe disease in about 15% of infected patients, COVID-19 is also found to have widespread effects throughout the body with a myriad of clinical manifestations including the endocrine system. This manuscript reviews what is known about the impact of COVID-19 on the pathophysiology and management of diabetes (both outpatient and inpatient) as well as pituitary, adrenal, thyroid, bone, and gonadal function. Findings in this area are evolving, and long-term effects of infection remain an active area of further research.

Immune checkpoint inhibitors and endocrine side effects, a narrative review

Immune checkpoint inhibitors (ICPIs) are novel drugs in the field of oncology however carry the risk of immune-related dermatologic, gastrointestinal, and endocrine side effects which can be fatal. These new innovative immunoregulatory drugs have intertwined the fields of oncology and endocrinology. CTLA-4 and PD-1 are co-inhibitory receptors on T cells that turn the T cell 'off' when binding to receptors on APCs. Tumor cells can also carry receptors for CTLA- and PD-1. By rendering T cells inactive, tumor cells can evade immune attack. Antibodies that bind to CTLA-4 and PD-1 lead to T cell activation and destruction of both tumor and normal host cells. ICPIs have been used in a variety of malignancies including melanoma, kidney cancer, and non-small cell lung cancer. A unique underrecognized side effect of the autoimmune response is hypophysitis leading to central adrenal insufficiency which can be fatal. Additional immune-related adverse events (irAEs) include hypothyroidism, hyperthyroidism, diabetes, and hypoparathyroidism.

Effects of Severe Hypoglycemia on Cardiovascular Outcomes and Death in the Veterans Affairs Diabetes Trial

OBJECTIVE

To determine the risk factors for severe hypoglycemia and the association between severe hypoglycemia and serious cardiovascular adverse events and cardiovascular and all-cause mortality in the Veterans Affairs Diabetes Trial (VADT).

RESEARCH DESIGN AND METHODS

This post hoc analysis of data from the VADT included 1,791 military veterans (age 60.5 ± 9.0 years) with suboptimally controlled type 2 diabetes (HbA1c 9.4 ± 2.0%) of 11.5 ± 7.5 years disease duration with or without known cardiovascular disease and additional cardiovascular risk factors. Participants were randomized to intensive (HbA1c <7.0%) versus standard (HbA1c <8.5%) glucose control.

RESULTS

The rate of severe hypoglycemia in the intensive treatment group was 10.3 per 100 patient-years compared with 3.7 per 100 patient-years in the standard treatment group (P < 0.001). In multivariable analysis, insulin use at baseline (P = 0.02), proteinuria (P = 0.009), and autonomic neuropathy (P = 0.01) were independent risk factors for severe hypoglycemia, and higher BMI was protective (P = 0.017). Severe hypoglycemia within the past 3 months was associated with an increased risk of serious cardiovascular events (P = 0.032), cardiovascular mortality (P = 0.012), and total mortality (P = 0.024). However, there was a relatively greater increased risk for total mortality in the standard group compared with the intensive group (P = 0.019). The association between severe hypoglycemia and cardiovascular events increased significantly as overall cardiovascular risk increased (P = 0.012).

CONCLUSIONS

Severe hypoglycemic episodes within the previous 3 months were associated with increased risk for major cardiovascular events and cardiovascular and all-cause mortality regardless of glycemic treatment group assignment. Standard therapy further increased the risk for all-cause mortality after severe hypoglycemia.

Profiling Heparin-Induced Thrombocytopenia (HIT) Antibodies in Hospitalized Patients With and Without Diabetes

Heparin (H) anticoagulation in populations characterized by elevated platelet factor 4 (PF4) frequently elicits PF4/H antibodies, presenting a risk of heparin-induced thrombocytopenia. Recent studies have shown that anti-PF4/H enzyme-linked immunosorbent assays (ELISAs) detect antibodies in individuals never exposed to heparin. Platelet factor 4/H cross-reactive antibodies may result from PF4-mediated defense responses to injury or infection. This study questioned whether patients with diabetes are more likely to develop the endogenous cross-reactive antibodies. A comparison of healthy volunteers versus hospitalized patients with or without diabetes showed no significant differences in the prevalence of PF4/H ELISA-positive results. However, the group of patients who had both diabetes and an infectious condition had higher median antibody titer compared to other patients with or without diabetes regardless of reason for hospitalization. Higher PF4/H titers were also associated with patients with diabetes who were not on any medical therapy. In the future, determining whether PF4/H cross-reactive antibodies sensitize patients to respond adversely to heparin anticoagulation or predispose patients to other complications may be relevant to diabetes care.

Facial Growth of Patients With Complete Unilateral Cleft Lip and Palate Treated With Alveolar Bone Grafting at 6 Years

Objective:

To investigate the effect that alveolar bone grafting (ABG) around 6 years of age has on facial growth by assessing craniofacial growth outcomes.

Design:

Retrospective cohort study.

Setting:

North American cleft centers.

Participants:

A total of 33 children with complete unilateral cleft lip and palate who were consecutively treated with secondary ABG around 6 years of age were compared to 148 participants from 4 centers with late secondary ABG.

Methods:

Preorthodontic standardized lateral cephalometric radiographs were analyzed and traced according to the Americleft Study protocol. Sixteen angular and 2 proportional measurements were performed. The outcomes of all ABG were assessed using the Standardized Way to Assess Graft scale. Measurement means from the study center (SC) were compared to 4 North American centers using analysis of variance and Welch modified t tests, and P < .05 was considered statistically significant.

Results:

For the SC, the mean age (SD) at the time of bone graft was 5.85 (0.71) years and the mean age at the time of the lateral cephalogram was 13.4 (1.8) years. The sagittal maxillary prominence of the SC was comparable to the 4 other centers. The mean SNA (78.1 [4.3]) for the SC was significantly higher compared to one center that used primary bone grafting ( P = .03). The soft tissue mean ANB (3.52 [4.09]) for the SC was significantly lower compared to 3 of the centers.

Conclusions:

Early secondary ABG around 6 years of age did not result in reduced midface projection as assessed by SNA and thus did not compromise anterior maxillary growth.

Standard vs. intensified management of heart failure to reduce healthcare costs: results of a multicentre, randomized controlled trial

Aims

To determine if an intensified form of heart failure management programme (INT-HF-MP) based on individual profiling is superior to standard management (SM) in reducing health care costs during 12-month follow-up (primary endpoint).

Methods and results

A multicentre randomized trial involving 787 patients (full analysis set) discharged from four tertiary hospitals with chronic HF who were randomized to SM (n = 391) or INT-HF-MP (n = 396). Mean age was 74 ± 12 years, 65% had HF with a reduced ejection fraction (31.4 ± 8.9%) and 14% were remote-dwelling. Study groups were well matched. According to Green, Amber, Red Delineation of rIsk And Need in HF (GARDIAN-HF) profiling, regardless of location, patients in the INT-HF-MP received a combination of face-to-face (home visits) and structured telephone support (STS); only 9% (`low risk') were designated to receive the same level of management as the SM group. The median cost in 2017 Australian dollars (A$1 equivalent to ∼EUR €0.7) of applying INT-HF-MP was significantly greater than SM ($152 vs. $121 per patient per month; P < 0.001), However, at 12 months, there was no difference in total health care costs for the INT-HF-MP vs. SM group (median $1579, IQR $644 to $3717 vs. $1450, IQR $564 to $3615 per patient per month, respectively). This reflected minimal differences in all-cause mortality (17.7% vs. 18.4%; P = 0.848) and recurrent hospital stay (18.6 ± 26.5 vs. 16.6 ± 24.8 days; P = 0.199) between the INT-HF-MP and SM groups, respectively.

Conclusion

During 12-months follow-up, an INT-HF-MP did not reduce healthcare costs or improve health outcomes relative to SM.

BIOTIN INTERFERENCE WITH ROUTINE CLINICAL IMMUNOASSAYS: UNDERSTAND THE CAUSES AND MITIGATE THE RISKS

OBJECTIVE

The objectives of this report are to review the mechanisms of biotin interference with streptavidin/biotin-based immunoassays, identify automated immunoassay systems vulnerable to biotin interference, describe how to estimate and minimize the risk of biotin interference in vulnerable assays, and review the literature pertaining to biotin interference in endocrine function tests.

METHODS

The data in the manufacturer's "Instructions for Use" for each of the methods utilized by seven immunoassay system were evaluated. We also conducted a systematic search of PubMed/MEDLINE for articles containing terms associated with biotin interference. Available original reports and case series were reviewed. Abstracts from recent scientific meetings were also identified and reviewed.

RESULTS

The recent, marked, increase in the use of over-the-counter, high-dose biotin supplements has been accompanied by a steady increase in the number of reports of analytical interference by exogenous biotin in the immunoassays used to evaluate endocrine function. Since immunoassay methods of similar design are also used for the diagnosis and management of anemia, malignancies, autoimmune and infectious diseases, cardiac damage, etc., biotin-related analytical interference is a problem that touches every area of internal medicine.

CONCLUSION

It is important for healthcare personnel to become more aware of immunoassay methods that are vulnerable to biotin interference and to consider biotin supplements as potential sources of falsely increased or decreased test results, especially in cases where a lab result does not correlate with the clinical scenario.

ABBREVIATIONS

FDA = U.S. Food & Drug Administration FT3 = free tri-iodothyronine FT4 = free thyroxine IFUs = instructions for use LH = luteinizing hormone PTH = parathyroid hormone SA/B = streptavidin/biotin TFT = thyroid function test TSH = thyroid-stimulating hormone.

Visit-to-visit systolic blood pressure variability and microvascular complications among patients with diabetes

AIMS

To examine the relationship between systolic blood pressure (SBP) variability and the risk of microvascular complications in a non-elderly diabetic population.

METHODS

This is a retrospective cohort study of individuals aged ≤60years treated for diabetes in 2003 in the US Department of Veterans Affairs healthcare system. Individuals were followed for five years for any new diagnosis of diabetic nephropathy, retinopathy, or neuropathy. In each year of follow-up, individuals were classified into quartiles based on their SBP variability.

RESULTS

We identified 208,338 patients with diabetes without diabetic nephropathy, retinopathy, or neuropathy at baseline. Compared to individuals with the least SBP variability (Quartile 1), those with most variability (Quartile 4) had 81% (OR=1.81; 95% CI, 1.72-1.91), 17% (OR=1.17; 95% CI, 1.13-1.21), 30% (OR=1.30; 95% CI, 1.25-1.35), and 19% (OR=1.19; 95% CI, 1.15-1.23) higher incidence of nephropathy, retinopathy, neuropathy, and any complication, respectively, after adjusting for mean SBP, demographic and clinical factors.

CONCLUSIONS

We found a significant graded relationship between SBP variability and the incidence of each complication and of any combined endpoint. This is the first study showing a significant association between SBP variability and the risk of diabetic retinopathy and neuropathy.

Incidence, Severity, and Outcomes of AKI Associated with Dual Renin-Angiotensin System Blockade

BACKGROUND AND OBJECTIVES

The benefit of dual blockade of the renin-angiotensin system is limited by adverse effects. We performed a secondary analysis of the Veterans Affairs Nephropathy in Diabetes (VA NEPHRON-D) Study to describe the effect of increased intensity of renin-angiotensin system blockade on the incidence, risk factors, and outcomes of AKI.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

In the VA NEPHRON-D Study, we randomized 1148 veterans receiving outpatient care with type 2 diabetes mellitus, eGFR of between 30 and 89.9 ml/min per 1.73 m2, and urinary albumin excretion of at least 300 μg/mg creatinine (or a urinary total protein of at least 0.5 mg/mg creatinine) to either combination therapy with losartan and lisinopril or monotherapy with losartan. We identified hospitalized AKI events and their outcomes during a median follow-up of 2.2 years through systematic reporting of serious adverse events.

RESULTS

The incidence of AKI was 12.2 (95% confidence interval, 10.5 to 14.0) versus 6.7 (95% confidence interval, 5.6 to 8.2) per 100 patient-years in the combination arm versus monotherapy arms (P<0.001). Individuals with AKI were more likely to develop the primary study end point of death, ESRD, or decline in kidney function (hazard ratio, 1.78; 95% confidence interval, 1.34 to 2.26; P<0.001). Patients with AKI in the combination arm had greater recovery of kidney function (75.9% versus 66.3%; P=0.04), lower 30-day mortality (4.7% versus 15.0%; P<0.01), and lower hazard for development of the primary study end point (hazard ratio, 0.60; 95% confidence interval, 0.37 to 0.98).

CONCLUSIONS

Dual renin-angiotensin system blockade was associated with an increased risk of AKI compared with monotherapy, but AKI in the setting of monotherapy was associated with lower rates of recovery of kidney function, higher mortality, and higher risk of progression of kidney disease.

Geographic Variation in Rosiglitazone Use Surrounding FDA Warnings in the Department of Veterans Affairs

BACKGROUND

Geographic variation in the use of prescription drugs, particularly those deemed harmful by the FDA, may lead to variation in patient exposure to adverse drug events. One such drug is the glucose-lowering drug rosiglitazone, for which the FDA issued a safety alert on May 21, 2007, following the publication of a meta-analysis that suggested a 43% increase in the risk of myocardial infarction with the use of rosiglitazone. This alert was followed by a black box warning on August 14, 2007, that was updated 3 months later. While large declines have been documented in rosiglitazone use in clinical practice, little is known about how the use of rosiglitazone and other glucose-lowering drugs varied within the Department of Veterans Affairs (VA), surrounding the FDA alerts. Understanding this variation within integrated health care systems is essential to formulating policies that enhance patient protection and quality of care.

OBJECTIVE

To document variation in the use of rosiglitazone and other glucose- lowering drugs across 21 Veterans Integrated Service Networks (VISNs).

METHODS

We conducted a retrospective analysis of drug use patterns for all major diabetes drugs in a national cohort of 550,550 veterans with diabetes from 2003 to 2008. This included the time periods when rosiglitazone was added to (November 2003) and removed from (October 2007) the VA national formulary (VANF). We employed multivariable logistic regression models to statistically estimate the association between a patient's location and the patient's odds of using rosiglitazone.

RESULTS

Aggregate rosiglitazone use increased monotonically from 7.7%, in the quarter it was added to the VANF (November 4, 2003), to a peak of 15.3% in the quarter when the FDA issued the safety alert. Rosiglitazone use decreased sharply afterwards, reaching 3.4% by the end of the study period (September 30, 2008). The use of pioglitazone, another glucose-lowering drug in the same class as rosiglitazone, was low when the FDA issued the safety alert (0.4%) but increased sharply afterwards, reaching 3.6% by the end of the study period. Insulin use increased monotonically; metformin use remained relatively flat; and sulfonylurea use exhibited a general declining trend throughout the study period. Statistically significant geographic variation was observed in rosiglitazone use throughout the study period. The prevalence range, defined as the range of minimum to maximum use across VISNs was 3.7%-12.4% in the first quarter (January 1 to March 31, 2003); 1.0%-5.5% in the last quarter of study period (July 1 to September 30, 2008); and reached a peak of 9.6%-25.5% in the quarter when the FDA safety alert was issued (April 1 to March 31, 2007). In 5 VISNs, peak rosiglitazone use occurred before the FDA issued the safety alert. The odds ratio of using rosiglitazone in a given VISN varied from 0.55 (95% CI = 0.52-0.59; VISN 10) to 1.58 (95% CI = 1.50-1.66; VISN 15), with VISN 1 being the reference region. The variation was higher in the periods after the FDA issued the safety alert. Much less variation was observed in the use of pioglitazone, metformin, sulfonylurea, and insulin.

CONCLUSIONS

Our results show statistically significant variation in the way VISNs within the VA responded to the FDA alerts, suggesting a need for mechanisms that disseminate information and guidelines for drug use in a consistent and reliable manner. Further study of regions that adopted ideal practices earlier may provide lessons for regional leadership and practice culture within integrated health care systems.

Systolic blood pressure variability and lower extremity amputation in a non-elderly population with diabetes

OBJECTIVE

Systolic blood pressure (SBP) variability is emerging as a new risk factor for cardiovascular diseases, diabetic nephropathy, and other atherosclerotic conditions. Our objective is to examine whether it has any prognostic value for lower-extremity amputations.

RESEARCH DESIGN AND METHODS

This is a nested case-control study of a cohort of patients with diabetes aged<60 years and treated in the US Department of Veterans Healthcare system in 2003. They were followed over five years for any above-ankle (major) amputations. For each case with a major amputation (event), we randomly selected up to five matched controls based on age, sex, race/ethnicity, and calendar time. SBP variability was computed using three or more blood pressure measures taken during the one-year period before the event. Patients were classified into quartiles according to their SBP variability.

RESULTS

The study sample included 1038 cases and 2932 controls. Compared to Quartile 1 (lowest variability), Quartile 2 had 1.4 times (OR=1.44, 95% CI=1.00-2.07) and Quartiles 3 and 4 (highest) had 2.5 times (OR for Quartile 3=2.62, 95% CI=1.85-3.72; OR for Quartile 4=2.50, 95% CI=1.74-3.59) higher risk of major amputation (P for trend<0.001). This gradient relationship held in both normotensive and hypertensive groups as well as for individuals without prior peripheral vascular disease.

CONCLUSIONS

This is the first study to show a significant graded relationship between SBP variability and risk of major amputation among non-elderly persons with diabetes.

Rosiglitazone treatment and cardiovascular disease in the Veterans Affairs Diabetes Trial

AIMS

To evaluate the relationship between patterns of rosiglitazone use and cardiovascular (CV) outcomes in the Veterans Affairs Diabetes Trial (VADT).

METHODS

Time-dependent survival analyses, case-control and 1 : 1 propensity matching approaches were used to examine the relationship between patterns of rosiglitazone use and CV outcomes in the VADT, a randomized controlled study that assessed the effect of intensive glycaemic control on CV outcomes in 1791 patients with type 2 diabetes (T2D) whose mean age was 60.4 ± 9 years. Participants were recruited between 1 December 2000 and 31 May 2003, and were followed for 5-7.5 years (median 5.6) with a final visit by 31 May 2008. Rosiglitazone (4 mg and 8 mg daily) was initiated per protocol in both the intensive-therapy and standard-therapy groups. Main outcomes included a composite CV outcome, CV death and myocardial infarction (MI).

RESULTS

Both daily doses of rosiglitazone were associated with lower risk for the primary composite CV outcome [4 mg: hazard ratio (HR) 0.63, 95% confidence interval (CI) 0.49-0.81 and 8 mg: HR 0.60, 95% CI 0.49-0.75] after adjusting for demographic and clinical covariates. A reduction in CV death was also observed (HR 0.25, p < 0.001, for both 4 and 8 mg/day rosiglitazone); however, the effect on MI was less evident for 8 mg/day and not significant for 4 mg/day.

CONCLUSIONS

In older patients with T2D the use of rosiglitazone was associated with decreased risk of the primary CV composite outcome and CV death. Rosiglitazone use did not lead to a higher risk of MI.

The effect of intensive glucose lowering therapy among major racial/ethnic groups in the Veterans Affairs Diabetes Trial

OBJECTIVE

To examine the effect of intensive glycemic control on cardiovascular disease events (CVD) among the major race/ethnic groups in a post-hoc analysis of the VADT.

MATERIALS AND METHODS

Participants included 1111 non-Hispanic Whites, 307 Hispanics and 306 non-Hispanic Blacks randomized to intensive or standard glucose treatment in VADT. Multivariable Cox proportional hazards models were constructed to assess the effect of intensive glucose treatment on CVD events among race/ethnic groups.

RESULTS

Mean age was 60.4 years and median follow-up was 5.6 years. By design, modifiable risk factors were managed equally well in both treatment arms and only differed modestly between race/ethnic groups. HbA(1c) decreased significantly from baseline with intensive glucose treatment in each race/ethnic group, with a trend for a greater response in Hispanics (P=0.02 for overall comparison between groups). Intensive glucose treatment was associated with reduced risk of CVD events for Hispanics but not for others (hazard ratios ranged from 0.54 to 0.75 for Hispanics whereas they were consistently close to 1 for others). Sensitivity analyses with different definitions of race/ethnicity or limited to individuals free of previous known CVD yielded similar results.

CONCLUSIONS

The results of these analyses support the hypothesis that race/ethnicity is worthy of consideration when tailoring intensive treatment for individuals with long-standing type 2 diabetes. However, additional studies are needed to confirm the findings of this post-hoc analysis.

Endothelial cell autoantibodies in predicting declining renal function, end-stage renal disease, or death in adult type 2 diabetic nephropathy

Albuminuria is a strong predictor of diabetic nephropathy chronic kidney disease outcomes. Yet, therapeutic albuminuria-lowering has not consistently translated into a reduction in clinical events suggesting the involvement of additional pathogenic factors. Our hypothesis is that anti-endothelial cell autoantibodies play a role in development and progression in diabetic nephropathy. We determined anti-endothelial cell antibody (AECA) bioactivity in protein A-elutes of baseline plasma in 305 participants in the VA NEPHRON-D study, a randomized trial of angiotensin receptor blocker (ARB) or dual ARB plus angiotensin-converting enzyme inhibitor therapy in type 2 diabetes with proteinuric nephropathy. Thirty-eight percent (117/305) of participants had significantly reduced endothelial cell survival ( ≤80%) in the IgG fraction of plasma. A VA NEPHRON-D primary endpoint [end-stage renal disease (ESRD), significant reduction in estimated glomerular filtration rate, or death] was experienced by 58 individuals. In adjusted Cox regression analysis, there was a significant interaction effect of baseline anti-endothelial cell-mediated cell survival and albuminuria on the hazard rate (HR) for primary composite endpoint (P = 0.017). Participants lacking strongly inhibitory antibodies with albuminuria ≥1 g/g creatinine had a significantly increased primary event hazard ratio, 3.41 - 95% confidence intervals (CI 1.84-6.33; P < 0.001) compared to those lacking strongly inhibitory antibodies with lower baseline albuminuria ( <1 g/g creatinine). These results suggest that anti-endothelial cell antibodies interact significantly with albuminuria in predicting the composite endpoint of death, ESRD, or substantial decline in renal function in older, adult type 2 diabetic nephropathy.

Combined angiotensin inhibition for the treatment of diabetic nephropathy

Combination therapy with angiotensin-converting-enzyme (ACE) inhibitors and angiotensin-receptor blockers (ARBs) decreases proteinuria; however, its safety and effect on the progression of kidney disease are uncertain. Methods We provided losartan (at a dose of 100 mg per day) to patients with type 2 diabetes, a urinary albumin-to-creatinine ratio (with albumin measured in milligrams and creatinine measured in grams) of at least 300, and an estimated glomerular filtration rate (GFR) of 30.0 to 89.9 ml per minute per 1.73 m(2) of body-surface area and then randomly assigned them to receive lisinopril (at a dose of 10 to 40 mg per day) or placebo. The primary end point was the first occurrence of a change in the estimated GFR (a decline of ≥ 30 ml per minute per 1.73 m(2) if the initial estimated GFR was ≥ 60 ml per minute per 1.73 m(2) or a decline of ≥ 50% if the initial estimated GFR was <60 ml per minute per 1.73 m(2)), end-stage renal disease (ESRD), or death. The secondary renal end point was the first occurrence of a decline in the estimated GFR or ESRD. Safety outcomes included mortality, hyperkalemia, and acute kidney injury. Results The study was stopped early owing to safety concerns. Among 1448 randomly assigned patients with a median follow-up of 2.2 years, there were 152 primary end-point events in the monotherapy group and 132 in the combination-therapy group (hazard ratio with combination therapy, 0.88; 95% confidence interval [CI], 0.70 to 1.12; P=0.30). A trend toward a benefit from combination therapy with respect to the secondary end point (hazard ratio, 0.78; 95% CI, 0.58 to 1.05; P=0.10) decreased with time (P=0.02 for nonproportionality). There was no benefit with respect to mortality (hazard ratio for death, 1.04; 95% CI, 0.73 to 1.49; P=0.75) or cardiovascular events. Combination therapy increased the risk of hyperkalemia (6.3 events per 100 person-years, vs. 2.6 events per 100 person-years with monotherapy; P<0.001) and acute kidney injury (12.2 vs. 6.7 events per 100 person-years, P<0.001). Conclusions Combination therapy with an ACE inhibitor and an ARB was associated with an increased risk of adverse events among patients with diabetic nephropathy. (Funded by the Cooperative Studies Program of the Department of Veterans Affairs Office of Research and Development; VA NEPHRON-D ClinicalTrials.gov number, NCT00555217.).

The duration of diabetes affects the response to intensive glucose control in type 2 subjects: the VA Diabetes Trial

BACKGROUND

The goal of the VA Diabetes Trial (VADT) was to determine the effect of intensive glucose control on macrovascular events in subjects with difficult-to-control diabetes. No significant benefit was found. This report examines predictors of the effect of intensive therapy on the primary outcome in this population.

METHODS

This trial included 1791 subjects. Baseline cardiovascular risk factors were collected by interview and the VA record. The analyses were done by intention to treat.

FINDINGS

Univariate analysis at baseline of predictors of a primary cardiovascular (CV) event included a prior CV event, age, insulin use at baseline, and duration of diagnosed diabetes (all P < .0001). Multivariable modeling revealed a U-shaped relationship between duration of diabetes and treatment. Modeled estimates for the hazard ratios (HRs) for treatment show that subjects with a short duration (3 years or less) of diagnosed diabetes have a nonsignificant increase in risk (HR > 1.0) after which the HR is below 1.0. From 7 to 15 years' duration at entry, subjects have HRs favoring intensive treatment. Thereafter the HR approaches 1.0 and over-21-years' duration approaches 2.0. Duration over 21 years resulted in a HR of 1.977 (CI 1.77-3.320, P < .01). Baseline c-peptide levels progressively declined up to 15 years and were stable subsequently.

INTERPRETATION

In difficult-to-control older subjects with type 2 DM, duration of diabetes altered the response to intensive glucose control. Intensive therapy may reduce CV events in subjects with a duration of 15 years or less and may increase risks in those with longer duration.

Profiling of heparin-induced thrombocytopenia antibody levels in patients with and without diabetes

Heparin/platelet factor 4 (H:PF4) antibodies are the causative agent in heparin-induced thrombocytopenia (HIT). The antibodies are frequently formed after exposure to heparin, most commonly without any signs of clinical HIT. Heparin-induced thrombocytopenia antibodies have been detected by enzyme-linked immunosorbent assay (ELISA) in individuals who have not been exposed to heparin. It is possible that the antibodies could be elicited by PF4 associated with endogenous, heparin-like glycosaminoglycans (GAGs). This risk would be higher in individuals with endothelial dysfunction and chronic platelet activation. In the setting of an outpatient endocrinology clinic, both diabetic and nondiabetic patients were studied and compared with healthy volunteers. Heparin/platelet factor 4 antibody titers were measured by ELISA and analyzed to determine the frequency of clinically seropositive responses, and median and interquartile ranges of baseline antibody titers. The study found no increase in frequency of ELISA-positive patients among diabetic patients. Moreover, the diabetic population had lower overall level of H:PF4 antibody titer, especially the subgroups treated with thiazolidinedione drugs or angiotensin receptor blockers. Further studies are needed to determine whether subthreshold titers of HIT antibody may be reflective of the physiological state of platelet/endothelial balance.

Ethnicity, race, and clinically significant macular edema in the Veterans Affairs Diabetes Trial (VADT)

OBJECTIVE

To determine risk factors in clinically significant macular edema (CSME) and if increased CSME in minorities is due to ethnicity or other factors in the Veterans Affairs Diabetes Trial (VADT).

METHODS

CSME prevalence based on 7-field stereo fundus photographs in 1268 patients with type 2 diabetes was related to ethnicity, demographics and biochemistries by univariate and multivariate analyses.

RESULTS

Hispanics (H) made up 17.5% and African Americans (AA) 17.7% of the cohort. CSME prevalence was 10%. In univariate analysis, CSME was more prevalent in H, 18%, and AA, 15.6% than in non-Hispanic Whites (NHW), 6.3%, p<0.01. Univariate regression of CSME associated with younger age, younger onset of diabetes; longer duration; retinopathy severity; and high HbA1c, BP, urine albumin/creatinine, and amputation, all p<0.01. In multivariate regression, CSME was associated with ethnicity/race (Hispanic White vs. non-Hispanic White, OR, (95% CI), 2.30, (1.35-3.92), p<0.01; African American vs. non-Hispanic White, 2.30, (1.33-4.00), p<0.01), diastolic BP (1.13 per 5 mm Hg, (1.02-1.23), p=0.03), amputation (3.0, (1.11-8.13), p=0.04), and retinopathy severity ( approximately 30, ( approximately 17 to approximately 59), p<0.01).

CONCLUSION

The prevalence of CSME in the VADT is associated with ethnicity as well as diastolic BP, amputation, and retinopathy severity.

Intensive glucose-lowering therapy reduces cardiovascular disease events in veterans affairs diabetes trial participants with lower calcified coronary atherosclerosis

OBJECTIVE

This study investigated the hypothesis that baseline calcified coronary atherosclerosis may determine cardiovascular disease events in response to intensive glycemic control within the Veterans Affairs Diabetes Trial (VADT).

RESEARCH DESIGN AND METHODS

At baseline, 301 type 2 diabetic participants in the VADT, a randomized trial comparing the effects of intensive versus standard glucose lowering on cardiovascular events, had baseline coronary atherosclerosis assessed by coronary artery calcium (CAC) measured by computed tomography. Participants were followed over the 7.5-year study for development of cardiovascular end points.

RESULTS

During a median follow-up duration of 5.2 years, 89 cardiovascular events occurred. Although intensive glucose-lowering therapy did not significantly reduce cardiovascular events in the substudy cohort as a whole, there was evidence that the response was modified by baseline CAC, as indicated by significant P values for treatment by log(CAC + 1) interaction terms in unadjusted and multivariable-adjusted models (0.01 and 0.03, respectively). Multivariable-adjusted hazard ratios (HRs) for the effect of treatment indicated a progressive diminution of benefit with increasing CAC. Subgroup analyses were also conducted for clinically relevant CAC categories: those above and below an Agatston score of 100. Among those randomized to intensive treatment, for the subgroup with CAC >100, 11 of 62 individuals had events, while only 1 of 52 individuals with CAC < or = 100 had an event. The multivariable HR for intensive treatment for those with CAC >100 was 0.74 (95% CI 0.46-1.20; P = 0.21), while for the subgroup with CAC < or = 100, the corresponding HR was 0.08 (0.008-0.77; P = 0.03), with event rates of 39 and 4 per 1,000 person-years, respectively.

CONCLUSIONS

These data indicate that intensive glucose lowering reduces cardiovascular events in those with less extensive calcified coronary atherosclerosis.

Comparison of dilated fundus examinations with seven-field stereo fundus photographs in the Veterans Affairs Diabetes Trial

OBJECTIVE

The Veterans Affairs Diabetes Trial (VADT) is a 20-medical center, prospective, randomized study of 1792 Type 2 diabetic individuals primarily aimed at determining whether intensive glycemic control prevents macrovascular events. We report a comparison of fundus photographs and ophthalmologic examination at baseline, permitting an evaluation of multiple settings similar to common clinical practice.

RESEARCH DESIGN AND METHODS

A 340-patient subset had both local dilated fundus examinations and centrally read seven-field stereo fundus photographs completed within 60 days of each other (median 28 days). Local examiners were unaware of the stereo photographs.

RESULTS

Overall, agreement within one step was 76% and exact agreement between ophthalmoscopy and central gradings of fundus photographs on a five-step retinopathy severity scale was 43% (weighted kappa 0.42, CI 0.35-0.48). In about 90% of disagreements the severity level was higher by photographic grading. The sensitivity for ophthalmoscopy compared to grading of fundus photographs for the detection of any retinopathy was 51% and specificity was 91%. For proliferative diabetic retinopathy (PDR), sensitivity was 61% and specificity 98%. Only one eye was high-risk PDR, and it was detected by both methods. For clinically significant macular edema, these measures were 24% and 98%, respectively. The disagreements were of possible clinical importance in three cases (<1%).

CONCLUSION

Most disagreements occurred in eyes rated near the milder end of a category and/or resulted from small differences between the ophthalmoscopic and photographic definitions used in classifying severity. There were reasonably few disagreements of possible clinical significance.

Glucose control and vascular complications in veterans with type 2 diabetes

BACKGROUND

The effects of intensive glucose control on cardiovascular events in patients with long-standing type 2 diabetes mellitus remain uncertain.

METHODS

We randomly assigned 1791 military veterans (mean age, 60.4 years) who had a suboptimal response to therapy for type 2 diabetes to receive either intensive or standard glucose control. Other cardiovascular risk factors were treated uniformly. The mean number of years since the diagnosis of diabetes was 11.5, and 40% of the patients had already had a cardiovascular event. The goal in the intensive-therapy group was an absolute reduction of 1.5 percentage points in the glycated hemoglobin level, as compared with the standard-therapy group. The primary outcome was the time from randomization to the first occurrence of a major cardiovascular event, a composite of myocardial infarction, stroke, death from cardiovascular causes, congestive heart failure, surgery for vascular disease, inoperable coronary disease, and amputation for ischemic gangrene.

RESULTS

The median follow-up was 5.6 years. Median glycated hemoglobin levels were 8.4% in the standard-therapy group and 6.9% in the intensive-therapy group. The primary outcome occurred in 264 patients in the standard-therapy group and 235 patients in the intensive-therapy group (hazard ratio in the intensive-therapy group, 0.88; 95% confidence interval [CI], 0.74 to 1.05; P=0.14). There was no significant difference between the two groups in any component of the primary outcome or in the rate of death from any cause (hazard ratio, 1.07; 95% CI, 0.81 to 1.42; P=0.62). No differences between the two groups were observed for microvascular complications. The rates of adverse events, predominantly hypoglycemia, were 17.6% in the standard-therapy group and 24.1% in the intensive-therapy group.

CONCLUSIONS

Intensive glucose control in patients with poorly controlled type 2 diabetes had no significant effect on the rates of major cardiovascular events, death, or microvascular complications with the exception of progression of albuminuria (P = 0.01) [added]. (ClinicalTrials.gov number, NCT00032487.)

Design of combination angiotensin receptor blocker and angiotensin-converting enzyme inhibitor for treatment of diabetic nephropathy (VA NEPHRON-D)

Both angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs) can slow the progression of diabetic nephropathy. Even with ACEI or ARB treatment, the proportion of patients who progress to end-stage renal disease (ESRD) remains high. Interventions that achieve more complete blockade of the renin-angiotensin system, such as combination ACEI and ARB, might be beneficial. This approach may decrease progression of nondiabetic kidney disease. In diabetic nephropathy, combination therapy decreases proteinuria, but its effect in slowing progression is unknown. In addition, the potential for hyperkalemia may limit the utility of combined therapy in this population. VA NEPHRON-D is a randomized, double-blind, multicenter clinical trial to assess the effect of combination losartan and lisinopril, compared with losartan alone, on the progression of kidney disease in 1850 patients with diabetes and overt proteinuria. The primary endpoints are time to (1) reduction in estimated GFR (eGFR) of > 50% (if baseline < 60 ml/min/1.73 m(2)); (2) reduction in eGFR of 30 ml/min/1.73 m(2) (if baseline > or = 60 ml/min/1.73 m(2)); (3) progression to ESRD (need for dialysis, renal transplant, or eGFR < 15 ml/min/1.73 m(2)); or (4) death. The secondary endpoint is time to change in eGFR or ESRD. Tertiary endpoints are cardiovascular events, slope of change in eGFR, and change in albuminuria at 1 yr. Specific safety endpoints are serious hyperkalemia (potassium > 6 mEq/L, requiring admission, emergency room visit, or dialysis), all-cause mortality, and other serious adverse events. This paper discusses the design and key methodological issues that arose during the planning of the study.

Proliferative diabetic retinopathy in type 2 diabetes is related to coronary artery calcium in the Veterans Affairs Diabetes Trial (VADT)

OBJECTIVE

Increasing evidence suggests that macrovascular disease and retinopathy may be more closely linked than previously believed. We determined the relationship between retinopathy and coronary atherosclerosis as measured by computed tomography-detectable coronary artery calcium (CAC).

RESEARCH DESIGN AND METHODS

The cross-sectional association between CAC and retinopathy was assessed on a Veteran Affairs Diabetes Trial subsample of 204 subjects with a mean duration of type 2 diabetes of 12.3 +/- 8.3 years.

RESULTS

Retinopathy was correlated with CAC (r = 0.19, P = 0.006). Median CAC increased across retinopathy categories: 197 in those with no retinopathy, 229 in those with microaneurysms only, 364 in those with mild nonproliferative diabetic retinopathy (NPDR), 300 in those with moderate to severe NPDR, and 981 in those with proliferative diabetic retinopathy (PDR). Stepwise multivariable linear regression analysis was performed to find a parsimonious subset of relevant risk factors to include along with PDR in predicting CAC. After adjustment for either this subset of standard factors (P = 0.047) or a more extensive panel of risk factors (P = 0.035), PDR was significantly associated with CAC. Moreover, using logistic regression, individuals with PDR were approximately sixfold more likely to have CAC >400 than those with no PDR, even after adjustment for other CVD risk factors.

CONCLUSIONS

These data indicate an important relationship between retinopathy and extent of CAC and suggest the potential to identify and treat shared risk factors for these common micro- and macrovascular complications.

Ethnicity, race, and baseline retinopathy correlates in the veterans affairs diabetes trial

OBJECTIVE

The Veterans Affairs Diabetes Trial (VADT) cohort is enriched with approximately 20% Hispanics and 20% African Americans, affording a unique opportunity to study ethnic differences in retinopathy.

RESEARCH DESIGN AND METHODS

Cross-sectional analyses on the baseline seven-field stereo fundus photos of 1,283 patients are reported here. Diabetic retinopathy scores are grouped into four classes of increasing severity: none (10-14), minimal nonproliferative diabetic retinopathy (NPDR) (15-39), moderate to severe NPDR (40-59), and proliferative diabetic retinopathy (60+). These four groups have also been dichotomized to none or minimal (10-39) and moderate to severe diabetic retinopathy (40+).

RESULTS

The prevalence of diabetic retinopathy scores >40 was higher for Hispanics (36%) and African Americans (29%) than for non-Hispanic whites (22%). The difference between Hispanics and non-Hispanic whites was significant (P < 0.05). Similarly, the prevalence of diabetic retinopathy scores >40 was significantly higher in African Americans than in non-Hispanic whites (P < 0.05). These differences could not be accounted for by an imbalance in traditional risk factors such as age, duration of diagnosed diabetes, HbA(1c) (A1C), and blood pressure. Diabetic retinopathy severity scores were also significantly associated with increasing years of disease duration, A1C, systolic and diastolic blood pressure, the degree of microalbuminuria, fibrinogen, and the percentage of patients with amputations. There was no relationship between retinopathy severity and the percentage of people who had strokes or cardiac revascularization procedures. There was an inverse relationship between retinopathy severity and total cholesterol, triglycerides, and plasminogen activator inhibitor-1 as well as with smoking history. Diabetic retinopathy scores were not associated with age.

CONCLUSIONS

In addition to many well-known associations with retinopathy, a higher frequency of severe diabetic retinopathy was found in the Hispanic and African-American patients at entry into the VADT that is not accounted for by traditional risk factors for diabetic retinopathy, and these substantial ethnic differences remain to be explained.

Health-related quality of life in the VA Feasibility Study on glycemic control and complications in type 2 diabetes mellitus

OBJECTIVE

The Veterans Affairs Cooperative Study in Diabetes Mellitus Type 2 Feasibility Trial (VA CSDM) studied standard and intensive glycemic treatment groups, achieving and maintaining for 27 months a difference in HbA1c of 2.1% (9.2% vs. 7.1%, respectively). A substudy planned in advance examined health status as assessed by a health status questionnaire obtained at baseline and 24 months.

DESIGN AND METHODS

A randomized, prospective trial was carried out at five VA Medical Centers from 1990 to 1993. The sample involved 153 male veterans 40-69 years of age and with diabetes duration of 8+/-4 years, who were suboptimally controlled with standard glucose lowering treatment. The participants were randomized to intensive and standard treatment groups. In addition to a variety of indicators of glycemic control and complications, health-related qualify of life data were assessed using a 20-question version of the Medical Outcome Study instrument. Scores were evaluated at baseline and 24 months for changes between the treatment groups.

RESULTS

The two groups were similar at baseline with respect to age, duration of diabetes, complications, comorbidities, and reported physical activity. The intensive treatment group had more frequent, mandatory self-glucose monitoring (vs. occasional measurement in the standard) and received two or more daily insulin injections (only one in the standard). This group had three times the number of clinic visits and 10-fold higher reported incidence of mild/moderate hypoglycemia. There were no significant changes in the health status over time in either the standard or intensive treatment groups, nor was there a difference between the two groups.

CONCLUSIONS

Intensive glucose control in advanced Type 2 diabetes mellitus (DM) has no effect on health status over 2 years. The successful lowering of glycemia does not improve health-related quality of life nor do the increased demands of an intensive therapy regimen worsen it.

Latent autoimmune diabetes of adulthood. Unique features that distinguish it from types 1 and 2

A number of patients with poor glycemic control receive the diagnosis of type 2 diabetes despite the fact that they do not exhibit some of the traditional characteristics of the disease, such as obesity. A more accurate diagnosis for many of these patients is latent autoimmune diabetes of adulthood (LADA). In this article, Dr Nabhan and coauthors describe features that LADA has in common with type 1 and type 2 diabetes, as well as those that distinguish LADA from these more widely recognized forms of diabetes. The authors also describe the pathogenesis of the disease, potential complications, and treatment options.

Effects of chronic ethanol (EtOH) administration on pro-inflammatory cytokines of the hypothalamic-pituitary-gonadal (HPG) axis in female rats

We and others have investigated the effects of acute and chronic ethanol (EtOH) administration on function of the hypothalamic-pituitary-gonadal (HPG) axis in female rats, consistently finding EtOH to be detrimental. There are now substantial data that pro-inflammatory cytokines, such as tumor necrosis factor alpha (TNFalpha) and interleukin 6 (IL-6), have anti-reproductive effects. If EtOH increased levels of these cytokines, such data would be consistent with, though not necessarily prove, a cytokine mediated mechanism for EtOH's deleterious effects on reproduction. Young adult female Sprague Dawley rats were used. In the experiment reported here, the Lieber DeCarli diet was used, with animals fed a 36% EtOH containing diet or pair fed an identical diet which contained dextrimaltose instead of EtOH. This was done for 4 to 6 weeks. TNFalpha and IL-6 were measured in the hypothalamus, pituitary, and ovary by ELISA. EtOH exposure resulted in significant increases in TNFalpha and IL-6 in hypothalami, pituitaries, and ovaries. The data reported here are the first to show consistent stimulatory effects of EtOH exposure on cytokines in the reproductive axis of female rats. Because the effects of these cytokines are generally anti-reproductive, these data provide a rational for more rigorous testing of the notion that part of EtOH's deleterious HPG effects may be due to such immuno-endocrine interactions.

Design of the cooperative study on glycemic control and complications in diabetes mellitus type 2: Veterans Affairs Diabetes Trial

INTRODUCTION

Long-term glycemic control trials in type 2 diabetes show as the main clinical benefit a difference in retinal photocoagulation (3/1000 in the UK Prospective Diabetes Study [UKPDS]), but no effect on visual acuity or renal failure. No intensive glycemic control trial has yet affected cardiovascular (CV) events, the main cause of morbidity and mortality. By contrast, modest blood pressure reduction has protective effects on visual acuity, renal function, CV events, and mortality. Optimal glycemic control goals are not established in elderly, obese persons with advanced complications, the most common patients in the Veterans Affairs (VA) system. The earlier feasibility trial in such patients (VA-CSDM) suggested potentially worse CV outcomes with lower attained hemoglobin A1c (HbA1c) levels.

OBJECTIVES

The primary objective of the Veterans Affairs Diabetes Trial (VADT) is the assessment of the effect of intensive glycemic treatment on CV events. Other objectives are effects on microangiopathy, quality of life, and cost effectiveness.

RESEARCH DESIGN AND METHODS

The VADT, started in December 2000, is enrolling 1700 men and women previously uncontrolled on insulin or maximum doses of oral agents at 20 VA medical centers. Accrual is 2 years and follow-up is 5-7 years, with visits every 1.5 months. The study has a power of 86% to detect a 21% relative reduction in major CV events (CV death, myocardial infarction [MI], cerebrovascular accident [CVA], congestive heart failure [CHF], revascularization and amputation for ischemia). Subjects are randomized to an intensive arm aiming at normal HbA1c levels or to a standard arm with usual, improved glycemic control. An HbA1c separation of >1.5% is to be maintained (expected 2%). Both arms receive step therapy: glimepiride or metformin plus rosiglitazone and addition of insulin or other oral agents to achieve goals. Strict control of blood pressure and dyslipidemia, daily aspirin, diet, and education are identical in both arms. Plasma fibrinogen, plasminogen-activating inhibitor I (PAI-I), lipids, renal function parameters, and ECG are measured throughout. Stereo retinal photographs are obtained at entry and 5 years, eye examinations yearly, and intervention as needed to prevent visual deterioration. Recruitment is proceeding on schedule: the current mean HbA1c at entry is 9.4+/-1.6% and mean duration of diagnosed diabetes 11+/-8 years.

Hepatic apoptosis and proliferation in male and female rats fed alcohol: role of cytokines

BACKGROUND

The female liver is more sensitive to the toxic effect of chronic alcohol intake than the male liver. The aim of the study was to compare the influence of gender and sex hormonal status on apoptosis and cell proliferation following chronic ethanol intake.

METHODS

Male and female rats were pair fed for 8 weeks a liquid diet containing 36% of their total daily calories as ethanol (ETOH group) or sucrose (control group). Liver samples were analyzed for apoptosis and hepatocyte proliferation by immunohistochemistry. The hepatic production of factors able to influence cell death and proliferation, such as tumor necrosis factor alpha (TNFalpha) and interleukin 6 (IL-6) were determined.

RESULTS

In both male and female rats, ethanol intake promoted apoptosis in the liver. This effect of ethanol was more evident in female than male rat livers. Hepatic TNFalpha levels, which promote apoptosis, are significantly more elevated in female than in male livers. Hepatic IL-6 production, which promotes hepatocyte proliferation, was induced by ethanol only in males, but not female animals.

CONCLUSION

This observed difference in cytokine responses may contribute to the enhanced sensitivity of female liver to EtOH-induced injury.

The response of the hypothalamic-pituitary-gonadal axis to fasting is modulated by leptin

Reproductive function is intimately related to caloric consumption. During fasting states, the hormones regulating reproduction, those of the hypothalamic-pituitary-gonadal axis, in particular, are severely altered. With the exciting observations that the obese (ob) gene product leptin, may also modulate neuroendocrine functions, we examined leptin's ability to prevent the consequences of fasting on reproductive hormones. Two groups of male rats, aged 65 days old, were either fasted and saline-injected or fasted and leptin-treated for approximately three days. Another group was given free access to rat chow. Leptin was able to prevent the fasting-induced fall of serum testosterone. Similar to testosterones dependence on leptin, leptin concentrations were somewhat dependent on testosterone. Castration accelerated the normal, age-related increase in serum leptin. Leptin also prevented the fasting-induced fall in luteinizing hormone (LH). The increase of beta-LH mRNA seen in the fasting state was prevented by leptin. There were no differences noted in luteinizing hormone releasing hormone (LHRH) mRNA among any of the groups. While neither fasting nor fasting plus leptin caused changes in serum prolactin, the increase in prolactin mRNA seen in fasted animals was prevented by leptin treatment. These data support the hypothesis that leptin plays a specific role in mediating the response of reproductive hormones to the nutritional status of the organism.

EtOH disrupts female mammalian puberty: age and opiate dependence

The major drug of abuse among teenagers in the United States continues to be ethanol (EtOH), but use is seen in children as young as nine. In the studies reported here, the impact of EtOH on biologic and hormonal parameters of puberty was assessed in female rats. Rats were fed a liquid diet containing EtOH, pair fed an identical liquid diet containing dextrimaltose instead of EtOH, or fed a liquid diet not containing EtOH ad libitum. Feeding was started at 21, 25, or 28 d of age. EtOH markedly delayed the age at vaginal opening (34.5 +/- 0.5 d in controls vs 48.5 +/- 2.4 d in EtOH animals; p < 0.001), delayed the age at first estrous (40.9 +/- 0.6 d in controls vs 61.2 +/- 2.6 d in EtOH animals; p < 0.001), increased the length of the estrous cycle, and decreased the number of proestrous days. EtOH, concomitant with reduced ovarian and uterine weight, decreased serum estradiol and progesterone. Associated with these changes in ovarian hormones there was a selective increase in follicle-stimulating hormone, but not luteinizing hormone. EtOH consistently reduced insulin-like growth factor-1. In general, EtOH-induced disruption was more severe the younger the animals were at the start of feeding. Opiate receptor blockade with naltrexone completely prevented the EtOH-induced delay in vaginal opening. The impact of EtOH on female puberty is dramatic, is an emerging public health problem, and deserves more study.

Alcohol and the male reproductive system

Alcohol use affects all three parts of the hypothalamic-pituitary-gonadal (HPG) axis, a system of endocrine glands and hormones involved in male reproduction. Alcohol use is associated with low testosterone and altered levels of additional reproductive hormones. Researchers are investigating several potential mechanisms for alcohol's damage. These mechanisms are related to alcohol metabolism, alcohol-related cell damage, and other hormonal reactions associated with alcohol consumption. Chronic alcohol use in male rats also has been shown to affect their reproductive ability and the health of their offspring.

Effect of intensive glycemic control on fibrinogen, lipids, and lipoproteins: Veterans Affairs Cooperative Study in Type II Diabetes Mellitus

BACKGROUND

The Veterans Affairs Cooperative Study in Type II Diabetes Mellitus prospectively studied insulin-treated patients with type 2 (non-insulin-dependent) diabetes mellitus, achieving 2.1% glycosylated hemoglobin separation between intensive- and standard-treatment arms (P<.001) for 2 years.

OBJECTIVE

To assess the effect of intensive therapy on serum fibrinogen and lipid levels, compared with standard treatment.

METHODS

One hundred fifty-three male subjects with type 2 diabetes mellitus and who required insulin treatment were recruited from 5 Veterans Affairs medical centers. The subjects were divided into intensive- and standard-treatment arms for a randomized prospective study. Dyslipidemia was managed identically in both arms (diet, drugs). Fibrinogen levels and lipid fractions were measured in the full cohort. Lipid fractions are separately reported in patients not treated with hypolipidemic agents.

RESULTS

There were no baseline differences between arms. Fibrinogen levels rose in the intensive-treatment arm at 1 year (from 3.34+/-0.12 to 3.75+/-0.15 g/L; P<.001) but returned to baseline at 2 years (3.47+/-0.12 g/L). There was no change in the standard-treatment arm. Triglyceride levels decreased in the intensive-treatment arm from 2.25+/-0.27 to 1.54+/-0.14 mmol/L (199+/-24 to 136+/-12 mg/ dL) at 1 year (P = .004) and to 1.74+/-0.18 mmol/L (154+/-16 mg/dL) at 2 years (P = .03); there was no change in the standard-treatment arm. Cholesterol levels decreased in the intensive-treatment arm at 1 year from 5.4+/-0.21 to 4.99+/-0.13 mmol/L (207+/-8 to 193+/-5 mg/dL) (P = .02); there was no change in the standard-treatment arm. Levels of low- and high-density lipoprotein cholesterol decreased in the standard-treatment arm only by 2 years, from 3.44+/-0.13 to 3.16+/-0.10 mmol/L (133+/-5 to 122+/-4 mg/ dL) (P =.02) and from 1.10+/-0.03 to 1.00+/-0.03 mmol/L (42+/-1 to 38+/-1 mg/dL) (P<.001) for low-density and high-density lipoprotein cholesterol, respectively. Levels of apolipoprotein B decreased in both treatment arms (P<.001), and apolipoprotein A1 levels decreased in the standard-treatment arm (P<.01). Lipoprotein (a) levels did not change in either treatment arm. Lipid results were essentially identical whether examined in the full cohort or excluding those patients receiving hypolipidemic agents.

CONCLUSIONS

Intensive insulin therapy led to a potentially beneficial reduction in serum triglyceride levels and preservation of high-density lipoprotein cholesterol and apolipoprotein A1 levels. However, it caused transient elevation in plasma fibrinogen levels, a possible thrombogenic effect.

Leptin alters the response of the growth hormone releasing factor- growth hormone--insulin-like growth factor-I axis to fasting

Proper nutritional status is critical for maintaining growth and metabolic function, playing an intimate role in neuroendocrine regulation. Leptin, the recently identified product of the obese gene, may very well be an integral signal which regulates neuroendocrine responses in times of food deprivation. The present study examines leptin's ability to regulate hormonal synthesis and secretion within the GRF-GH-IGF axis in the adult male rat during almost 3 days of fasting. Serum levels of GH and IGF-I were drastically suppressed by fasting. Daily leptin administration was able to fully prevent the fasting-induced fall in serum GH. Leptin failed to restore IGF-I to control levels, however, suggesting possible GH resistance. Fasting caused an insignificant increase in GH mRNA, while leptin injections significantly increased steady-state levels of this message. The GRF receptor (GRFr) message was not altered with fasting or leptin treatment. Leptin also exhibited effects at the hypothalamic level. Fasting induced a sharp fall in GRF mRNA expression and leptin injections partially prevented this fall. However, there were no observed changes in the hypothalamic GRF content. These results provide evidence that leptin may function as a neuromodulator of the GRF-GH-IGF axis communicating to this hormonal system the nutritional status of the animal.

The impact of acute ethanol on reproductive hormone synthesis, processing, and secretion in female rats at proestrous

It is the purpose of this study to investigate the effects of acute ethanol (EtOH) on the female rat hypothalamic-pituitary-gonadal (HPG) axis. The molecular and cellular mechanistic details of such effects have been studied intensively in the male rat. However, there has been relatively little in-depth study of EtOH's effects on the adult, postpubertal female rat. Adult female rats with confirmed 4- or 5-day estrous cycles were given a single injection of EtOH or saline between noon and 1:00 PM on proestrous and were killed at 4:00 PM. EtOH caused a sharp 97% reduction in luteinizing hormone (LH) serum levels (p < 0.001), compared with controls with no concomitant change in LH mRNA. EtOH also significantly reduced hypothalamic LH releasing hormone (LHRH) by 49% (p < 0.01), with no change in content of the precursor pro-LHRH compared with saline-injected controls. The ratio of LHRH to pro-LHRH was also significantly reduced by EtOH (p < 0.05), compared with control. There was no EtOH-induced change in LHRH mRNA. Compared with saline, EtOH reduced both serum estradiol by 37% (p < 0.02) and progesterone by 47% (p < 0.001). These results show that EtOH has profound disruptive effects on the female HPG axis. Our data suggests that EtOH decreases the releasable LHRH pool either by decreasing conversion of pro-LHRH to LHRH and/or by increasing local LHRH degradation. This acutely restricts the release of LH and subsequent estradiol and progesterone secretion.

The effect of acute ethanol (EtOH) exposure on protein kinase C (PKC) activity in anterior pituitary

Alterations in the protein kinase C (PKC) pathway may interrupt anterior pituitary luteinizing hormone (LH) synthesis and/or secretion, which may impair normal reproductive function. Work by our laboratory and others has shown that EtOH has profound deleterious effects on the regulation of the hypothalamic-pituitary-gonadal (HPG) axis. The present study focuses on PKC translocation from the cytosol to the membrane of anterior pituitary after acute EtOH exposure. Serum levels of LH were measured at three time points (15, 30, and 90 min) after an IP injection of either saline or 3 g/kg EtOH in adult castrated male rats. LH levels dropped significantly (p < 0.03) in EtOH-injected compared to saline-injected control animals. In the same animals, EtOH significantly suppressed PKC localization at its active site at the pituitary cell membrane (p < 0.05). These findings suggest that the mechanism of EtOH's suppression of LH is mediated, at least in part, through a decrease in PKC translocation to the anterior pituitary cell membrane.

The endocrine system: alcohol alters critical hormonal balance

Alcohol's effects on the hormonal (i.e., endocrine) system have widespread consequences for virtually the entire body. Alcohol-related hormonal disturbances can result in cardiovascular abnormalities and reproductive deficits in both males and females. Other endocrine problems stemming from excess alcohol consumption include immune dysfunction and bone disease. Researchers are exploring ways of using hormonal mechanisms to help treat alcoholics as well as to identify people predisposed to alcoholism.

Evaluations of retinopathy in the VA Cooperative Study on Glycemic Control and Complications in Type II Diabetes (VA CSDM). A feasibility study

OBJECTIVE

The main goal of the study of 153 male veterans was to determine whether a statistically and clinically significant difference in HbA1c could be achieved between a standard therapy and an intensively treated group of patients with type II diabetes. A second major goal was to assess the feasibility of collecting reliable high-quality endpoint data, including microvascular and macrovascular events. Retinopathy was defined as a key microvascular endpoint.

RESEARCH DESIGN AND METHODS

This was a randomized prospective trial of 153 men between the ages of 40 and 69 years, with type II diabetes for 15 years or less. Of the patients, 78 were assigned to the standard therapy arm and 75 to the intensive therapy arm. The goal of standard therapy was good general medical care and well-being and avoiding excessive hyperglycemia, glycosuria, ketonuria, or hypoglycemia. This was generally accomplished with one shot of insulin per day. The goal of intensive therapy was to obtain an HbA1c within two standard deviations of the mean of nondiabetic subjects (4.0-6.1%). This was obtained by a four-step management technique, with patients moving to the next step only if operational goals were not met. The steps were as follows: step 1: evening intermediate or long-acting insulin only; step 2: evening insulin with daytime glipizide; step 3: insulin, twice a day, no glipizide; and step 4: more than two injections of insulin, no glipizide. Retinopathy was assessed at baseline, 12, and 24 months by seven-field stereo fundus photography done at each of the five participating VA medical centers and read at the Central Reading Center at the Department of Ophthalmology, University of Wisconsin Medical School, Madison. Visual acuity was determined by ophthalmologists at each of the participating hospitals.

RESULTS

After the 6th month of the 24-month study, an average HbA1c of approximately 7.1% in the intensively treated group was sustained for the full study and was significantly lower than that seen in the standard group (9.2%, P < 0.001). Compliance in obtaining fundus photographs was excellent. Near normalization of glycemia did not cause transient worsening of retinal morphology nor did it prevent the onset or delay the progression of retinopathy. There was no effect on visual acuity.

CONCLUSIONS

1) A glycemic control intervention study in people with type II diabetes is feasible and safe; 2) intensive control did not cause transient deterioration of retinopathy; and 3) although no improvement was seen in retinopathy, the follow-up was 24 months, an interval shorter than the 3 years or more of intensive therapy before improvement is seen in type 1 diabetic studies. This does not rule out the possibility that longer periods of intensive therapy would have improved retinopathy. A full-scale intervention trial in type II diabetes is needed to resolve this issue.

Ethanol-induced alterations in the posttranslational processing, but not secretion of luteinizing hormone-releasing hormone in vitro

The effects of ethanol (EtOH) on the male hypothalamic pituitary reproductive axis are multiple and varied. Although direct gonadal toxicity has been reported, hypothalamic-pituitary perturbations have also been noted. The difficulty of sampling the hypothalamus has made direct investigation of EtOH-induced alterations on luteinizing hormone-releasing hormone (LHRH) fraught with interpretation problems. To circumvent this, we have conducted a series of experiments exploring the effect of 200 mg% EtOH in vitro on GT1-7 cells, a newly developed LHRH secreting neural cell line. Cell lines were treated with EtOH-containing or EtOH-free media for 2, 6, 24, or 48 hr. EtOH caused no significant change in LHRH secretion at any time point, although there was a trend to increased secretion after 2 hr EtOH exposure when compared with control. Significantly increased total (i.e., cellular plus secreted) pro-LHRH coupled with significantly reduced cellular LHRH after 6 hr only of EtOH exposure suggested that EtOH caused a transient decrease in processing from bioinactive pro-LHRH to bioactive LHRH. However, even at this time point, LHRH secretion from these EtOH-exposed cells was no different than from control cells. Steady-state LHRH mRNA levels were not changed by EtOH at any time point. These findings are concordant with previous in vitro data using hypothalamic tissue that has similarly demonstrated no effect of EtOH on LHRH secretion. Taken together with the in vivo demonstration that EtOH reduces hypothalamic-pituitary portal blood levels of LHRH, these data indicate that EtOH exerts its effect either at an extrahypothalamic locus and/or on non-LHRH-producing cells within the hypothalamus.

Glycemic control and complications in type II diabetes. Design of a feasibility trial. VA CS Group (CSDM)

OBJECTIVE

To determine, after 1 yr of follow-up in type II diabetes patients, whether a statistically and clinically significant difference can be achieved in HbA1c between a standard therapy group and an intensively treated group, while maintaining HbA1c levels in both groups within ranges acceptable in regular community practice. Secondary objectives include assessment of patient adherence to protocol, side effects, and accuracy of data collection.

RESEARCH DESIGN AND METHODS

This is a prospective, randomized, controlled VA CS conducted with 151 patients at five VAMCs. Patients are males, age 40-69 yr, treated at entry with a maximum dose of sulfonylurea or with insulin, exhibiting an HbA1c level > 3 SDs above the normal mean (5.05 + 3 x 0.50 = > 6.55%). Standard control is achieved with insulin and intensive control with a step-up regimen including insulin alone or insulin/glipizide combinations. Education and management of cardiovascular risk factors are handled similarly in both groups. Primary macrovascular end points are nonfatal myocardial infarction, congestive heart failure, stroke, amputation, and cardiovascular death. Primary microvascular end points are appearance and progression of retinopathy, documented by centrally read seven-field-stereo fundus photographs. Other measured indicators include resting and ambulatory ECGs, ventricular function (MUGA scan), serum lipid and apolipoprotein levels, plasma fibrinogen, nonsymptomatic peripheral vasculopathy, neuroautonomic status by heart-beat variation on Valsalva maneuver, and microalbuminuria.

CONCLUSIONS

This study may be the basis for a long-term trial, involving 1400 patients, to assess the long-term effects of metabolic control on macro- and microvascular end points.

Brain thyroid-stimulating hormone: effects of endocrine manipulations

We have previously described the presence of and the immunologic, chromatographic and biologic characteristics of a thyroid-stimulating hormone (TSH)-like peptide, widely distributed in the rat and monkey central nervous system (CNS). In order to test the hypothesis that brain TSH, specifically hypothalamic TSH, participates in the turnover of pituitary TSH, we have assessed the effect on hypothalamic TSH of two endocrine manipulations, castration and adrenalectomy, known to significantly decrease pituitary and/or serum TSH in the rat. Orchidectomy led to a significant decline of pituitary and serum TSH while a significant increase in hypothalamic TSH concentrations was seen. Adrenalectomy also led to decreased pituitary concentration of TSH linked with a significant increase in hypothalamic TSH levels. Neither manipulation led to changes in TSH in the extrahypothalamic brain. The inverse relationship wherein serum and/or pituitary TSH decrease is accompanied by an increase in hypothalamic TSH is compatible with a role for hypothalamic TSH in pituitary TSH regulation. The possible significance of these findings in terms of TSH triiodothyronine interactions in the CNS is discussed.

Subcellular localization of hypothalamic luteinizing hormone

Ultracentrifugation and sucrose gradient separation techniques have been applied to study of the subcellular distribution of hypothalamic luteinizing hormone (LH). Subcellular particle-bound LH accounted for 42% of the total LH while cytoplasm contained 58% of the total immunoassayable LH in these extracts. 70% of particle-bound LH was present in the P2 fraction and most of the particle-associated LH was found in subfractions of P2 rich in synaptosomes but poor in myelin and mitochondria. While actual amounts of LH in the P3 and P4, the microsomal fractions, were relatively small, the concentration of LH, expressed as nanograms per milligram of protein was quite high. Both content and concentration of LH in the nuclear pellet, P1, were substantially lower. These findings provide further framework for speculation on the role of brain-based LH.