Exploring potential mediators of the cardiovascular benefit of dulaglutide in type 2 diabetes patients in REWIND

BACKGROUND

The REWIND trial demonstrated cardiovascular (CV) benefits to patients with type 2 diabetes and multiple CV risk factors or established CV disease. This exploratory analysis evaluated the degree to which the effect of dulaglutide on CV risk factors could statistically account for its effects on major adverse cardiovascular events (MACE) in the REWIND trial.

METHODS

Potential mediators of established CV risk factors that were significantly reduced by dulaglutide were assessed in a post hoc analysis using repeated measures mixed models and included glycated hemoglobin (HbA1c), body weight, waist-to-hip ratio, systolic blood pressure, low-density lipoprotein (LDL), and urine albumin/creatinine ratio (UACR). These factors, for which the change in level during follow-up was significantly associated with incident MACE, were identified using Cox regression modeling. Each identified variable was then included as a covariate in the Cox model assessing the effect of dulaglutide on MACE to estimate the degree to which the hazard ratio of dulaglutide vs placebo was attenuated. The combined effect of the variables associated with attenuation was assessed by including all variables in an additional Cox model.

RESULTS

Although all evaluated variables were significantly improved by treatment, only changes in HbA1c and UACR were associated with MACE and a reduction in the effect of dulaglutide on this outcome was observed. The observed hazard ratio for MACE for dulaglutide vs placebo reduced by 36.1% by the updated mean HbA1c, and by 28.5% by the updated mean UACR. A similar pattern was observed for change from baseline in HbA1c and UACR and a reduction of 16.7% and 25.4%, respectively in the hazard ratio for MACE with dulaglutide vs placebo was observed. When HbA1c and UACR were both included, the observed hazard ratio reduced by 65.4% for the updated mean and 41.7% for the change from baseline with no HbA1c-UACR interaction (P interaction = 0.75 and 0.15, respectively).

CONCLUSIONS

Treatment-induced improvement in HbA1c and UACR, but not changes in weight, systolic blood pressure, or LDL cholesterol, appear to partly mediate the beneficial effects of dulaglutide on MACE outcomes. These observations suggest that the proven effects of dulaglutide on cardiovascular disease benefit are partially related to changes in glycemic control and albuminuria, with residual unexplained benefit. Clinicaltrials.gov; Trial registration number: NCT01394952. URL: https://clinicaltrials.gov/ct2/show/NCT01394952.

HbA1c Change and Diabetic Retinopathy During GLP-1 Receptor Agonist Cardiovascular Outcome Trials: A Meta-analysis and Meta-regression

BACKGROUND

Long-term glycemic control reduces retinopathy risk, but transient worsening can occur with glucose control intensification. Glucagon-like peptide 1 receptor agonists (GLP-1RA) lower glucose, but the long-term impact on retinopathy is unknown. GLP-1RA cardiovascular outcome trials (CVOTs) provide long-term follow-up, allowing examination of retinopathy outcomes.

PURPOSE

To examine the associations between retinopathy, HbA_1c, systolic blood pressure (SBP), and weight in GLP-1RA CVOTs.

DATA SOURCES

Systematic review identified six placebo-controlled GLP-1RA CVOTs reporting prespecified retinopathy outcomes.

STUDY SELECTION

Published trial reports were used as the primary data sources.

DATA EXTRACTION

HbA_1c, SBP, and weight data throughout follow-up by treatment group were extracted.

DATA SYNTHESIS

Random-effects model meta-analysis showed no association between GLP-1RA treatment and retinopathy (odds ratio [OR] 1.10; 95% CI 0.93, 1.30), with high heterogeneity between studies (I ² = 52.2%; Q statistic P = 0.063). Univariate meta-regression showed an association between retinopathy and average HbA_1c reduction during the overall follow-up (slope = 0.77, P = 0.007), but no relationship for SBP or weight. Sensitivity analyses for HbA_1c showed a relationship at 3 months (P = 0.006) and 1 year (P = 0.002). A 0.1% (1.09 mmol/mol) increase in HbA_1c reduction was associated with 6%, 14%, or 8% increased Ln(OR) for retinopathy at the 3-month, 1-year, and overall follow-up, respectively.

LIMITATIONS

CVOTs were not powered to assess retinopathy outcomes and differed in retinopathy-related criteria and methodology. The median follow-up of 3.4 years is short compared with the onset of retinopathy.

CONCLUSIONS

HbA_1c reduction was significantly associated with increased retinopathy risk in meta-regression for GLP-1RA CVOTs. The magnitude of HbA_1c reduction was correlated with retinopathy risk in people with diabetes and additional cardiovascular risk factors, but the long-term impact of improved glycemic control on retinopathy was unmeasured in these studies. Retinopathy status should be assessed when intensifying glucose-lowering therapy.

Clinical Outcomes by Albuminuria Status with Dulaglutide versus Insulin Glargine in Participants with Diabetes and CKD: AWARD-7 Exploratory Analysis

Background

In the AWARD-7 trial of participants with type 2 diabetes (T2DM) and moderate-to-severe CKD, dulaglutide (DU) treatment slowed decline in eGFR compared with insulin glargine (IG). Treatment with doses of either DU or IG resulted in similar levels of glycemic control and BP. The aim of this analysis was to determine the risk of clinical event outcomes between treatment groups.

Methods

Participants with T2DM and CKD categories 3-4 were randomized (1:1:1) to 0.75 or 1.5 mg DU weekly or IG daily as basal therapy, with titrated insulin lispro, for 1 year. The time to occurrence of the composite outcome of ≥40% eGFR decline, ESKD, or death due to kidney disease was compared using a Cox proportional-hazards model.

Results

Patients treated with 1.5 mg DU weekly versus IG daily for 1 year had a lower risk of ≥40% eGFR decline or ESKD events in the overall study population (5% versus 11%; hazard ratio, 0.45; 95% CI, 0.20 to 0.97; P=0.04). Most events occurred in the subset of patients with macroalbuminuria, where risk of the composite outcome was substantially lower for 1.5 mg DU versus IG (7% versus 22%; hazard ratio, 0.25; 95% CI, 0.10 to 0.68; P=0.006). No deaths due to kidney disease occurred.

Conclusions

Treatment with 1.5 mg DU weekly was associated with a clinically relevant risk reduction of ≥40% eGFR decline or ESKD compared with IG daily, particularly in the macroalbuminuria subgroup of participants with T2DM and moderate-to-severe CKD.

OR30-06 Assessment of Dulaglutide Safety in Older Patient Populations in Rewind

Background: Dulaglutide (DU) was superior to placebo (PL) in reducing the incidence of Major Adverse Cardiovascular Events in the Researching Cardiovascular Events with a Weekly INcretin in Diabetes (REWIND Study) broad patient population. The safety of DU treatment is also of interest to health care providers who treat an older patient population (≥65 years of age).

Aims: The primary objective of this post-hoc analysis was to evaluate DU safety in the REWIND patient subgroup populations categorized by age (≥ 65 and < 65 years) with regards to the occurrence of the composite safety outcome of overall mortality and severe hypoglycemia. One of the key secondary objectives was first occurrence of severe hypoglycemia.

Methods: Patients were grouped into two age groups: ≥65 and <65 years. Time-to-event for the composite safety endpoint as well as individual variables were analyzed using Cox proportional hazards regression. Hazard ratios (HRs) and 95% confidence intervals (CIs) for between group treatment differences were also calculated.

Results: Of the 9,901 patients randomized in REWIND, a total of 5,256 (DU, 2,619; PL, 2,637) were aged ≥65 years. The incidence of the composite safety outcome for patients aged ≥65 years was 399 of 2619 (15.2%) for DU-treated patients and 425 of 2,637 (16.1%) for PL-treated patients. The incidence of the composite safety outcome for those aged <65 years was 188 of 2,330 (8.1%) for DU-treated patients and 224 of 2,315 (9.7%) for PL-treated patients. Between group treatment differences (HR [95% CI]) were 0.94 (0.82, 1.08) for patients ≥65 years of age and 0.82 (0.68, 1.00) for patients <65 years of age; interaction p-value = 0.277. The incidence of the secondary outcome of first occurrence of severe hypoglycemia for patients aged ≥65 years was 46 of 2619 (1.8%) for DU-treated patients and 49 of 2,637 (1.9%) for PL-treated patients. The incidence of this outcome for patients <65 years was 18 of 2,330 (0.8%) for DU-treated patients and 25 of 2,315 (1.1%) for PL-treated patients. Between group treatment differences (HR [95% CI]) were 0.95 (0.63, 1.42) for patients ≥65 years of age and 0.71 (0.39, 1.31) for patients <65 years of age; interaction p-value = 0.443. The safety profile of DU was reviewed based upon the results of subgroup analysis of treatment emergent adverse events and serious adverse events by preferred terms for comparing PL and DU for age subgroups (≥65 years of age versus <65 years). None of the results indicated that DU has a different safety profile across the age subgroups evaluated in this post-hoc analysis.

Conclusions: Treatment with DU demonstrated similar safety in REWIND patients aged ≥65 years and those aged <65 years. Dulaglutide can be considered a safe and effective treatment option for use in older adults.

Body weight and eGFR during dulaglutide treatment in type 2 diabetes and moderate-to-severe chronic kidney disease (AWARD-7)

In patients with type 2 dibetes and moderate-to-severe chronic kidney disease, dulaglutide treatment led to body weight (BW) loss and lesser eGFR decline compared to insulin glargine. As BW may affect muscle mass, creatinine-based eGFR can be altered independently of kidney function. Cystatin C-based eGFR is not affected by muscle mass. The objective of this post-hoc analysis was to determine whether the lesser eGFR decline with dulaglutide was related to BW loss. Baseline characteristics were similar between treatments ([mean ± SD] age, 64.6 ± 8.6 years; women, 48%; BW, 89.1 ± 17.7 kg; eGFR [CKD-EPI-cystatin C] 38 ± 14 mL/min/1.73m² ). BW decreased with dulaglutide 1.5 and 0.75 mg and increased with insulin glargine ([LSM change (SE)], -2.66 [0.47] kg and -1.71 [0.45] vs 1.57 [0.43] kg; P < 0.001). Changes in eGFR were not significant with dulaglutide 1.5 and 0.75 mg, but eGFR significantly decreased with insulin glargine (eGFR-CKD-EPI-cystatin C [LSM change (95%CI)], -0.7 [-2.5, 1.0] and -0.7 [-2.4, 1.1] vs -3.3 [-5.1, -1.6] mL/min/1.73 m² ; P ≤ 0.037 vs glargine). Changes in BW did not correlate with changes in eGFR-CKD-EPI-cystatin C (r = -0.041; n = 471; P = 0.379) or eGFR-CKD-EPI-creatinine (r = -0.074; n = 473; P = 0.106). In conclusion, the lesser decline in eGFR observed with dulaglutide was not influenced by BW loss.

Generalizability of glucagon-like peptide-1 receptor agonist cardiovascular outcome trials to the overall type 2 diabetes population in the United States

AIM

To examine the generalizability of results from glucagon-like peptide-1 receptor agonist (GLP-1 RA) cardiovascular outcome trials (CVOTs) in the US type 2 diabetes (T2D) population.

MATERIALS AND METHODS

Patients enrolled or eligible for inclusion in four CVOTs (EXSCEL, LEADER, REWIND, and SUSTAIN-6) were examined in reference to a retrospective clinical database weighted to match the age and sex distribution of the US adult T2D population. We descriptively compared key baseline characteristics of the populations enrolled in each trial to those of the reference population and estimated the proportions of individuals in the reference population represented by those in the trials for each characteristic. We also estimated the proportions of individuals in the reference population that might have been enrolled in each trial based upon meeting the trial inclusion and exclusion (I/E) criteria.

RESULTS

No trial's enrolled population perfectly matched the reference population in key characteristics. The EXSCEL population most closely matched in mean age (62.7 vs. 60.5 years) and percentage with estimated glomerular filtration rate <60 (18.6 vs. 17.3%), while REWIND most closely matched in HbA1c, sex distribution, and proportion with a prior myocardial infarction. Based on I/E criteria, 42.6% of the reference population were eligible for enrolment in REWIND, versus 15.9% in EXSCEL, 13.0% in SUSTAIN-6, and 12.9% in LEADER.

CONCLUSIONS

Although none of the trials are fully representative of the general population, among the four trials examined, results from baseline REWIND were found to be more generalizable to the US adult T2D population than those of other GLP-1 RA CVOTs.

Dulaglutide versus insulin glargine in patients with type 2 diabetes and moderate-to-severe chronic kidney disease (AWARD-7): a multicentre, open-label, randomised trial

BACKGROUND

Many antihyperglycaemic drugs, including insulin, are primarily cleared by the kidneys, restricting treatment options for patients with kidney disease. Dulaglutide is a long-acting glucagon-like peptide-1 receptor agonist that is not cleared by the kidneys, and confers a lower risk of hypoglycaemia than does insulin. We assessed the efficacy and safety of dulaglutide in patients with type 2 diabetes and moderate-to-severe chronic kidney disease.

METHODS

AWARD-7 was a multicentre, open-label trial done at 99 sites in nine countries. Eligible patients were adults with type 2 diabetes and moderate-to-severe chronic kidney disease (stages 3-4), with an HbA_1c of 7·5-10·5%, and who were being treated with insulin or insulin plus an oral antihyperglycaemic drug and were taking a maximum tolerated dose of an angiotensin-converting enzyme inhibitor or an angiotensin receptor blocker. Participants were randomly assigned (1:1:1) by use of a computer-generated random sequence with an interactive response system to once-weekly injectable dulaglutide 1·5 mg, once-weekly dulaglutide 0·75 mg, or daily insulin glargine as basal therapy, all in combination with insulin lispro, for 52 weeks. Insulin glargine and lispro doses were titrated as per an adjustment algorithm; dulaglutide doses were masked to participants and investigators. The primary outcome was HbA_1c at 26 weeks, with a 0·4% non-inferiority margin. Secondary outcomes included estimated glomerular filtration rate (eGFR) and urine albumin-to-creatinine ratio (UACR). The primary analysis population was all randomly assigned patients who received at least one dose of study treatment and had at least one post-randomisation HbA_1c measurement. The safety population was all patients who received at least one dose of study treatment and had any post-dose data. This study is registered with ClinicalTrials.gov, number NCT01621178.

FINDINGS

Between Aug 15, 2012, and Nov 30, 2015, 577 patients were randomly assigned, 193 to dulaglutide 1·5 mg, 190 to dulaglutide 0·75 mg, and 194 to insulin glargine. The effects on HbA_1c change at 26 weeks of dulaglutide 1·5 mg and 0·75 mg were non-inferior to those of insulin glargine (least squares mean [LSM] -1·2% [SE 0·1] with dulaglutide 1·5 mg [183 patients]; -1·1% [0·1] with dulaglutide 0·75 mg [180 patients]; -1·1% [0·1] with insulin glargine [186 patients]; one-sided p≤0·0001 for both dulaglutide doses vs insulin glargine). The differences in HbA_1c concentration at 26 weeks between dulaglutide and insulin glargine treatments were LSM difference -0·05% (95% CI -0·26 to 0·15, p<0·0001) with dulaglutide 1·5 mg and 0·02% (-0·18 to -0·22, p=0·0001) with dulaglutide 0·75 mg. HbA_1c-lowering effects persisted to 52 weeks (LSM -1·1% [SE 0·1] with dulaglutide 1·5 mg; -1·1% [0·1] with dulaglutide 0·75 mg; -1·0% [0·1] with insulin glargine). At 52 weeks, eGFR was higher with dulaglutide 1·5 mg (Chronic Kidney Disease Epidemiology Collaboration equation by cystatin C geometric LSM 34·0 mL/min per 1·73 m² [SE 0·7]; p=0·005 vs insulin glargine) and dulaglutide 0·75 mg (33·8 mL/min per 1·73 m² [0·7]; p=0·009 vs insulin glargine) than with insulin glargine (31·3 mL/min per 1·73 m² [0·7]). At 52 weeks, the effects of dulaglutide 1·5 mg and 0·75 mg on UACR reduction were not significantly different from that of insulin glargine (LSM -22·5% [95% CI -35·1 to -7·5] with dulaglutide 1·5 mg; -20·1% [-33·1 to -4·6] with dulaglutide 0·75 mg; -13·0% [-27·1 to 3·9] with insulin glargine). Proportions of patients with any serious adverse events were similar across groups (20% [38 of 192] with dulaglutide 1·5 mg, 24% [45 of 190] with dulaglutide 0·75 mg, and 27% [52 of 194] with insulin glargine). Dulaglutide was associated with higher rates of nausea (20% [38 of 192] with dulaglutide 1·5 mg and 14% [27 of 190] with 0·75 mg, vs 5% [nine of 194] with insulin glargine) and diarrhoea (17% [33 of 192] with dulaglutide 1·5 mg and 16% [30 of 190] with 0·75 mg, vs 7% [14 of 194] with insulin glargine) and lower rates of symptomatic hypoglycaemia (4·4 events per patient per year with dulaglutide 1·5 mg and 4·3 with dulaglutide 0·75 mg, vs 9·6 with insulin glargine). End-stage renal disease occurred in 38 participants: eight (4%) of 192 with dulaglutide 1·5 mg, 14 (7%) of 190 with dulaglutide 0·75 mg, and 16 (8%) of 194 with insulin glargine.

INTERPRETATION

In patients with type 2 diabetes and moderate-to-severe chronic kidney disease, once-weekly dulaglutide produced glycaemic control similar to that achieved with insulin glargine, with reduced decline in eGFR. Dulaglutide seems to be safe to use to achieve glycaemic control in patients with moderate-to-severe chronic kidney disease.

FUNDING

Eli Lilly and Company.

The effect of teriparatide compared with risedronate on reduction of back pain in postmenopausal women with osteoporotic vertebral fractures

The effect of teriparatide and risedronate on back pain was tested, and there was no difference in the proportion of patients experiencing a reduction in back pain between groups after 6 or 18 months. Patients receiving teriparatide had greater increases in bone mineral density and had fewer vertebral fractures.

INTRODUCTION

This study aimed to understand the effect of teriparatide in reducing back pain in patients with prevalent back pain and vertebral fracture compared to risedronate.

METHODS

In an 18-month randomized, double-blind, double-dummy trial, we investigated the effects of teriparatide (20 μg/day) vs. risedronate (35 mg/week) in postmenopausal women with back pain likely due to vertebral fracture. The primary objective was to compare the proportion of subjects reporting ≥30% reduction in worst back pain severity from baseline to 6 months as assessed by a numeric rating scale in each treatment group. Pre-specified secondary and exploratory outcomes included assessments of average and worst back pain at additional time points, disability and quality of life, bone mineral density, incidence of fractures, and safety.

RESULTS

At 6 months, 59% of teriparatide and 57% of risedronate patients reported ≥30% reduction in worst back pain and there were no differences between groups in the proportion of patients experiencing reduction in worst or average back pain at any time point, disability, or quality of life. There was a greater increase from baseline in bone mineral density at the lumbar spine (p = 0.001) and femoral neck (p = 0.02) with teriparatide compared to risedronate and a lower incidence of vertebral fractures at 18 months (4% teriparatide and 9% risedronate; p = 0.01). Vertebral fractures were less severe (p = 0.04) in the teriparatide group. There was no difference in the overall incidence of adverse events.

CONCLUSIONS

Although there were no differences in back pain-related endpoints, patients receiving teriparatide had greater skeletal benefit than those receiving risedronate.

The reversible effects of raloxifene on luteinizing hormone levels and ovarian morphology in mice

Raloxifene is a selective estrogen receptor modulator that has estrogen agonist effects on bone and serum lipids and estrogen antagonist effects on breast and uterine tissues. This study assessed the effects of raloxifene hydrochloride (HCl) treatment on circulating luteinizing hormone (LH) levels and ovarian morphology in sexually mature, 15-week-old, female CD-1 mice. Mice were maintained on diets providing average daily doses of 0 or 233 mg/kg raloxifene for 2 weeks (Study 1) or 0, 7.9, or 236 mg/kg raloxifene for 4 weeks (Study 2). At the end of the treatment period, blood samples were collected every 2 hours for 24 h in Study 1 (5 mice per group) and at 10:00 a.m. and 10:00 p.m. in Study 2 (8 mice per group). Serum LH levels were measured by radioimmunoassay. Ovarian histomorphology was evaluated in the 10 mice per group (Study 1) and the 8 mice per group (Study 2). For the reversibility phase (Study 2), mice were fed untreated diets for 3 weeks; serum LH levels and ovarian histomorphology were then assessed. Raloxifene treatment at 233 mg/kg/day for 2 weeks (Study 1) significantly elevated circulating LH levels by 4- to 7-fold compared with control. Raloxifene-treated mice had elevated LH levels sustained over the 24-h sampling period and did not exhibit the preovulatory LH surge evident in some control mice at the 4:00 p.m., 6:00 p.m., and 8:00 p. m. time points. Mice treated with 236 mg/day raloxifene for 4 weeks (Study 2) had elevated LH levels (4.4-fold compared to control), whereas mice exposed to 7.9 mg/kg/day raloxifene had a slight, nonsignificant increase in LH (2-fold compared to control). In both dose groups, LH levels were indistinguishable from controls 3 weeks after raloxifene treatment was discontinued. The ovaries in six of the eight mice treated with 7.9 mg/kg/day raloxifene had dilated and/or anovulatory follicles. One mouse in this group had a single hemorrhagic follicle; however, corpora lutea distribution was normal, indicating that ovulation was occurring. Raloxifene-treated mice in Study 1 and mice treated with a comparable raloxifene dose (236 mg/day) in Study 2 had histomorphological changes in the ovary indicative of arrested follicular maturation, including anovulatory hemorrhagic follicles, some developing follicles, and very few corpora lutea. At the end of the reversibility phase, hemorrhagic follicles were no longer evident and follicular maturation and corpora lutea distribution were normal. Raloxifene treatment in mice produces a dose-dependent, sustained elevation in serum LH levels and is associated with changes in ovarian follicular morphology. These changes are reversible upon discontinuation of raloxifene treatment.

Healthcare use among U.S. women aged 45 and older: total costs and costs for selected postmenopausal health risks

The purpose of this study is to estimate the level of healthcare use and costs incurred by postmenopausal women overall and for these selected conditions: cardiovascular disease, osteoporosis, breast cancer, and gynecological cancers. National healthcare survey and discharge data were used to estimate healthcare use by women aged 45 and older. Clinical Classification for Health Policy Research (CCHPR) codes were used to identify patients whose primary diagnosis or procedure corresponded with the selected conditions. National weights were used to estimate resource use. Treatment costs were estimated using cost/charge ratios or the Medicare fee schedule to calculate costs for each individual procedure. Estimated total annual medical care treatment costs for women 45 and older were about $186 billion in 1997 dollars, including about $60.4 billion for cardiovascular disease, $12.9 billion for osteoporosis, and $5.0 billion for breast and gynecological cancers. For each condition, estimated resource use and costs are reported for hospitalization, outpatient, nursing home, and home healthcare services. Resource use and costs are also reported by age and expected source of payment. The economic burden of disease for conditions commonly affecting postmenopausal women is substantial. Prior research establishes that hormone replacement therapy (HRT) may be effective in reducing the burden of disease among women who continue preventive therapy for many years, but few at-risk women do so. New alternatives for prevention, such as selective estrogen receptor modulators (SERMs), may be effective in reducing the burden of disease among postmenopausal women.

Lithium as a potential adjuvant to 131I therapy of metastatic, well differentiated thyroid carcinoma

As lithium inhibits the release of iodine from the thyroid but does not change iodine uptake, it may potentiate 131I therapy of thyroid cancer. The effects of lithium on the accumulation and retention of 131I in metastatic lesions and thyroid remnants were evaluated in 15 patients with differentiated thyroid carcinoma. Two 131I turnover studies were performed while the patients were hypothyroid. One was performed while the patient received lithium; the second served as a control study. From a series of gamma-camera images, it was found that lithium increased 131I retention in 24 of 31 metastatic lesions and in 6 of 7 thyroid remnants. A comparison of 131I retention during lithium with that during the control period showed that the mean increase in the biological or retention half-life was 50% in tumors and 90% in remnants. This increase occurred in at least 1 lesion in each patient and was proportionally greater in lesions with poor 131I retention. When the control biological half life was less than 3 days, lithium prolonged the effective half-life, which combines both biological turnover and isotope decay, in responding metastases by more than 50%. More 131I also accumulated during lithium therapy, probably as a consequence of its effect on iodine release. The increase in the accumulated 131I and the lengthening of the effective half-life combined to increase the estimated 131I radiation dose in metastatic tumor by 2.29 +/- 0.58 (mean +/- SEM) times. These studies suggest that lithium may be a useful adjuvant for 131I therapy of thyroid cancer, augmenting both the accumulation and retention of 131I in lesions.

Neuropsychiatric manifestations of altered thyroid state

The authors assessed the mood and cognitive effects of sequential T4, T3, and withdrawal of thyroid hormone replacement on 25 patients who had had thyroidectomies for thyroid cancer. The patients experienced increased sadness and anxiety when they were without medication, but not significant difference in mood was noted between T4 and T3. The patients who experienced increased affective symptoms when not taking medication were more likely to have histories of affective illness or mood lability.

Thoracic stimulation and prolactin secretion

Although galactorrhea and/or enhanced prolactin (PRL) secretion have been reported with a variety of thoracic stimuli, the effect of thoracic stimulation on dynamic prolactin secretion is not clear. A 49-year-old woman with ventilatory muscle weakness from polio presented with galactorrhea, and intermittent hyperprolactinemia but regular menses. The galactorrhea was noted following the use of a new, tight fitting cuirass (thoracic apparatus which assists ventilation). To determine if the new, "tight" cuirass elicited enhanced PRL secretion, and to assess more extensively the effect of such thoracic stimulation on PRL secretion, serum PRL was measured during brief and prolonged stimulation, sleep, and pharmacological manipulation of PRL. Basal PRL was normal (less than 25 ng/ml) and increased during brief stimulation (1 hour) with the "tight" (137%) and "loose" cuirass (140%). Although the absolute increments were similar, the "tight" cuirass elicited an earlier PRL peak than the "loose" cuirass and the PRL began to decrease while the "tight" cuirass was still functioning. Several hours of thoracic stimulation resulted in a transient rise in PRL and a fall to normal, prestimulatory levels despite persistent stimulation. During this stimulation, PRL did not rise after sleep nor after insulin-induced hypoglycemia despite normal cortisol and GH increments, but the PRL response after TRH was exaggerated.(ABSTRACT TRUNCATED AT 250 WORDS)

Changes in blood pressure and plasma noradrenaline in short-term hypothyroidism

Thirteen patients who had undergone thyroidectomy for thyroid cancer stopped thyroid hormone replacement prior to follow-up radioactive iodine scans. Thyroxine was replaced by triiodothyronine (T3) for 4 weeks and T3 was stopped 2 weeks before the scan and 16 to 19 days before blood pressure measurement and venipuncture for obtaining plasma noradrenaline samples. During this time, a small but significant decrease in systolic blood pressure occurred, both supine and standing, while the corresponding plasma noradrenaline levels increased significantly. These findings indicate that the acute cardiovascular effect of brief thyroid hormone withdrawal is a decrease in blood pressure rather than the increase often observed in chronic hypothyroidism, and that plasma noradrenaline levels may increase much sooner than previously reported after onset of hypothyroidism.

Hospital admissions caused by iatrogenic disease

Complications of medical therapy requiring hospitalization affect the costs and quality of medical care. We studied all admissions to the medical services of a public teaching hospital to characterize current incidence and cause of iatrogenic admissions. We studied 834 admissions resulting in 47 distinct iatrogenic events and 45 iatrogenic admissions (5.4%). Thirty-five cases were caused by medications, nine by procedures, one by radiotherapy, one by transfusional therapy, and one by nosocomial infection. Almost 50% of these admissions were avoidable. Though the incidence of iatrogenic admissions in this study is similar to that in previous reports, the profile of the responsible agents is different. We did not find relationships with age, number or type of diagnoses, or number of medications on admission. Study of other patient and physician characteristics may be more rewarding in reducing the number of iatrogenic complications.

Enzymic profiles of bovine pancreatic ductal and acinar tissues

The plasma membrane enzymes, alkaline phosphatase, bicarbonate-dependent adenosine triphosphatase, 5'-nucleotidase, and carbonate dehydratase, were measured in ductal and acinar preparations of bovine pancreas. Epithelial cells were scraped from the main duct and a piece of acinar tissue was dissected from the whole pancreas for homogenization. All enzymes studied demonstrated higher levels in the duct per milligram protein than in the acinus: bicarbonate-dependent adenosine triphosphatase was 2.8 times higher; 5'-nucleotidase, 4.1 times higher; carbonate dehydratase, 16.9 times higher, while alkaline phosphatase showed only a slight increase in the duct compared to acini.