A Phase II, Randomized, Double Blind, Placebo Controlled Study of the Safety and Efficacy of a Caffeine-Based Antifibrosis Cream in Patients with Breast Cancer Undergoing Radiation Therapy

PURPOSE/OBJECTIVE(S)

Radiation induced fibrosis (RIF) is a common long term adverse event in patients undergoing post-mastectomy radiation therapy (PMRT) which can cause capsular contracture, implant loss, and reconstruction complications in women with implant-based breast reconstruction. At a molecular level, adenosine is a driver of RIF. Preclinical data have shown that pharmacologic blockade of the adenosine A2A Receptor (A2AR) in mice as well as an A2AR knockout mouse model prevented skin fibrosis associated with radiation injury. Caffeine is an A2AR antagonist which has been shown to block the development of hepatic fibrosis in liver disease patients. We present a phase II placebo controlled clinical trial to evaluate whether a caffeine-based cream can prevent RIF and thus reduce the rates of reconstructive complications in patients with tissue expander-based reconstruction requiring PMRT.

MATERIALS/METHODS

Women ≥ 18 years old with breast carcinoma stage 0-III status post mastectomy with tissue expander-based reconstruction who require PMRT to the chest wall +/- the regional nodes are being enrolled. The target accrual is 60 patients. Boost field to the chest wall, scar and/or nodal region is allowed. Patients with inflammatory breast cancer or those requiring skin bolus are excluded. Prior to starting radiation, patients will be randomized to placebo vs. caffeine cream and they will be instructed to apply the cream twice a day starting on the first day of radiation treatment and continuing daily for the duration of radiation until the removal of tissue expanders. The primary study endpoint is reconstructive complications requiring rehospitalization or reoperation by 2 years post radiation including reconstructive failure with or without reconstruction. A safety endpoint of grade ≥ 2 acute radiation dermatitis will also serve as a co-primary endpoint. Secondary endpoints are wound infection/cellulitis, hematoma, seroma, threatened exposure, wound dehiscence, implant leakage, rupture, and or deflation, and capsular contracture that do not meet criteria for the primary endpoint. Clinician rated cosmesis, local recurrence, regional recurrence, distant metastasis and survival up to 4 years are additional secondary endpoints. Exploratory endpoint includes the use of shear wave elastography (SWE) as a potential tool to quantitatively measure post irradiation fibrosis. Correlative aims include assessing epidermal thickness and fat layer thickness from tissue obtained at time of implant exchange for association with the development of fibrosis. The primary efficacy endpoint will be estimated using Kaplan Meier methods from date of randomization. Treatment comparisons will be based on a 2-sided log rank chi-square test and the hazard ratio will be estimated with 95% confidence intervals. The study started accruing in 12/2019 and is estimated to end by 04/2024. As of January 2023, 67% (40/60 patients) of the planned patients have been enrolled.

RESULTS

To be determined.

CONCLUSION

To be determined.

Bone and non-contractile soft tissue changes following open kinetic chain resistance training and testosterone treatment in spinal cord injury: an exploratory study

Twenty men with spinal cord injury (SCI) were randomized into two 16-week intervention groups receiving testosterone treatment (TT) or TT combined with resistance training (TT + RT). TT + RT appears to hold the potential to reverse or slow down bone loss following SCI if provided over a longer period.

INTRODUCTION

Persons with SCI experience bone loss below the level of injury. The combined effects of resistance training and TT on bone quality following SCI remain unknown.

METHODS

Men with SCI were randomized into 16-week treatments receiving TT or TT + RT. Magnetic resonance imaging (MRI) of the right lower extremity before participation and post-intervention was used to visualize the proximal, middle, and distal femoral shaft, the quadriceps tendon, and the intermuscular fascia of the quadriceps. For the TT + RT group, MRI microarchitecture techniques were utilized to elucidate trabecular changes around the knee. Individual mixed models were used to estimate effect sizes.

RESULTS

Twenty participants completed the pilot trial. A small effect for yellow marrow in the distal femur was indicated as increases following TT and decreases following TT + RT were observed. Another small effect was observed as the TT + RT group displayed greater increases in intermuscular fascia length than the TT arm. Distal femur trabecular changes for the TT + RT group were generally small in effect (decreased trabecular thickness variability, spacing, and spacing variability; increased network area). Medium effects were generally observed in the proximal tibia (increased plate width, trabecular thickness, and network area; decreased trabecular spacing and spacing variability).

CONCLUSIONS

This pilot suggests longer TT + RT interventions may be a viable rehabilitation technique to combat bone loss following SCI.

CLINICAL TRIAL REGISTRATION

Registered with clinicaltrials.gov : NCT01652040 (07/27/2012).

Osteoporosis care amidst the prolonged pandemic

As SARS-CoV-2 stunned and overtook everyone's lives, multiple daily briefings, protocols, policies and incident command committees were mobilized to provide frontline staff with the tools, supplies and infrastructure needed to address the COVID-19 pandemic. Medical resources were immediately shifted. In light of the necessity for self-isolation, telemedicine was expanded, although there has been concern than non-pandemic disorders were being ignored. Ambulatory care services such as bone densitometry and osteoporosis centered clinics came to a near halt. Progress with fracture prevention has been challenged. Despite the prolonged pandemic and the consequent sense of exhaustion, we must re-engage with chronic bone health concerns and fracture prevention. Creating triaging systems for bone mineral testing and in person visits, treating individuals designated as high risk of fracture using fracture risk assessment tools such as FRAX, maintaining telemedicine, leveraging other bone health care team members to monitor and care for osteoporotic patients, and re-engaging our primary care colleagues will remain paramount but challenging. The pandemic persists. Thus, we will summarize what we have learned about COVID-19 and bone health and provide a framework for osteoporosis diagnosis, treatment, and follow-up with the extended COVID-19 pandemic. The goal is to preserve bone health, with focused interventions to sustain osteoporosis screening and treatment initiation/maintenance rates.

Consensus statement from 2nd International Conference on Controversies in Vitamin D

The 2nd International Conference on Controversies in Vitamin D was held in Monteriggioni (Siena), Italy, September 11-14, 2018. The aim of this meeting was to address ongoing controversies and timely topics in vitamin D research, to review available data related to these topics and controversies, to promote discussion to help resolve lingering issues and ultimately to suggest a research agenda to clarify areas of uncertainty. Several issues from the first conference, held in 2017, were revisited, such as assays used to determine serum 25-hydroxyvitamin D [25(OH)D] concentration, which remains a critical and controversial issue for defining vitamin D status. Definitions of vitamin D nutritional status (i.e. sufficiency, insufficiency and deficiency) were also revisited. New areas were reviewed, including vitamin D threshold values and how they should be defined in the context of specific diseases, sources of vitamin D and risk factors associated with vitamin D deficiency. Non-skeletal aspects related to vitamin D were also discussed, including the reproductive system, neurology, chronic kidney disease and falls. The therapeutic role of vitamin D and findings from recent clinical trials were also addressed. The topics were considered by 3 focus groups and divided into three main areas: 1) "Laboratory": assays and threshold values to define vitamin D status; 2) "Clinical": sources of vitamin D and risk factors and role of vitamin D in non-skeletal disease and 3) "Therapeutics": controversial issues on observational studies and recent randomized controlled trials. In this report, we present a summary of our findings.

Correction to: Hip fracture trends in the United States, 2002 to 2015

The name of the first author, E.M. Lewiecki, was rendered incorrectly in the original publication. The publisher regrets any inconvenience and is pleased to correct the error here.

MANAGEMENT OF ENDOCRINE DISEASE: Therapeutics of Vitamin D

OBJECTIVE

The central role of vitamin D in bone health is well recognized. However, controversies regarding its clinical application remain. We therefore aimed to review the definition of hypovitaminosis D, the skeletal and extra-skeletal effects of vitamin D and the available therapeutic modalities.

DESIGN

Narrative and systematic literature review.

METHODS

An international working group that reviewed the current evidence linking bone and extra-skeletal health and vitamin D therapy to identify knowledge gaps for future research.

RESULTS

Findings from observational studies and randomized controlled trials (RCTs) in vitamin D deficiency are discordant, with findings of RCTs being largely negative. This may be due to reverse causality with the illness itself contributing to low vitamin D levels. The results of many RCTs have also been inconsistent. However, overall evidence from RCTs shows vitamin D reduces fractures (when administered with calcium) in the institutionalized elderly. Although controversial, vitamin D reduces acute respiratory tract infections (if not given as bolus monthly or annual doses) and may reduce falls in those with the lowest serum 25-hydroxyvitamin D (25OHD) levels. However, despite large ongoing RCTs with 21 000–26 000 participants not recruiting based on baseline 25OHD levels, they will contain a large subset of participants with vitamin D deficiency and are adequately powered to meet their primary end-points.

CONCLUSIONS

The effects of long-term vitamin D supplementation on non-skeletal outcomes, such as type 2 diabetes mellitus (T2DM), cancer and cardiovascular disease (CVD) and the optimal dose and serum 25OHD level that balances extra-skeletal benefits (T2DM) vs risks (e.g. CVD), may soon be determined by data from large RCTs.

Hip fracture trends in the United States, 2002 to 2015

An analysis of United States (US) Medicare claims data from 2002 to 2015 for women aged ≥ 65 years found that age-adjusted hip fracture rates for 2013, 2014, and 2015 were higher than projected, resulting in an estimated increase of more than 11,000 hip fractures.

INTRODUCTION

Hip fractures are a major public health concern due to high morbidity, mortality, and healthcare expenses. Previous studies have reported a decrease in the annual incidence of hip fractures in the US beginning in 1995, coincident with the introduction of modern diagnostic tools and therapeutic agents for osteoporosis. In recent years, there has been less bone density testing and fewer prescriptions for osteoporosis treatments. The large osteoporosis treatment gap raises concern of possible adverse effects on hip fracture rates.

METHODS

We assessed hip fracture incidence in the US to determine if the previous decline in hip fracture incidence continued. Using 2002 to 2015 Medicare Part A and Part B claims for women ≥ 65 years old, we calculated age-adjusted hip fracture rates, weighting to the 2014 population.

RESULTS

We found that hip fracture rates declined each year from 2002 to 2012 and then plateaued at levels higher than projected for years 2013, 2014, and 2015.

CONCLUSIONS

The plateau in age-adjusted hip fracture incidence rate resulted in more than 11,000 additional estimated hip fractures over the time periods 2013, 2014, and 2015. We recommend further study to assess all factors contributing to this remarkable change in hip fracture rate and to develop strategies to reduce the osteoporosis treatment gap.

Glucocorticoid exposure and fracture risk in patients with new-onset rheumatoid arthritis

Retrospective claims analysis indicated that high levels of daily and cumulative doses of systemic glucocorticoids were associated with elevated fracture risk in a large cohort of new RA patients under age 65. Heightened risk began to decline within months of discontinuation. Findings were similar among patients age <50 years.

INTRODUCTION

We evaluated the impact of systemic glucocorticoid exposure on fracture risk among relatively young patients with new-onset rheumatoid arthritis (RA).

METHODS

Using administrative data, we identified 42,127 RA patients diagnosed January 1, 2005-December 31, 2012, age 18-64 years, with benefits coverage for ≥12 months before RA diagnosis. Follow-up extended to clinical fracture, cancer diagnosis, or December 31, 2012. Glucocorticoid users were new to therapy. Fracture incidence rates (IR) were stratified by glucocorticoid exposure expressed as prednisone equivalent doses. Cox's proportional hazards models estimated fracture risk adjusted for demographics and baseline clinical characteristics to assess dose-response relationships with current (daily) and prior (cumulative) dose, and by time since discontinuation.

RESULTS

Most patients (85 %) had glucocorticoid exposure. Exposed and unexposed patients were demographically similar (74 % female; mean age 49.7 and 48.8 years); 1 % had prior fracture. Fracture IRs (95 % confidence intervals) were 5 to 9 per 1000 person-years at doses <15 mg/day, 16.0 (11.0, 22.6) at doses ≥15 mg/day, and 13.4 (10.7, 16.7) at cumulative doses ≥5400 mg. Adjusted fracture risk was approximately 2-fold higher at highest dose levels compared with 0 mg/day current daily dose and <675 mg cumulative dose, respectively. Fracture risk was 29 % lower at 60-182 days post-discontinuation compared with ongoing use and was similar to unexposed patients by 12 months. Findings were similar among patients age <50 years.

CONCLUSIONS

Among younger, new-onset RA patients, fracture risk was significantly elevated at high levels of daily and cumulative dose, and was similar to unexposed patients by 12 months post-discontinuation.

Analysis of osteoporosis treatment patterns with bisphosphonates and outcomes among postmenopausal veterans

PURPOSE

Adherence and persistence with bisphosphonates are frequently poor, and stopping, restarting, or switching bisphosphonates is common. We evaluated bisphosphonate change behaviors (switching, discontinuing, or reinitiating) over time, as well as fractures and costs, among a large, national cohort of postmenopausal veterans.

METHODS

Female veterans aged 50+ treated with bisphosphonates during 2003-2011 were identified in Veterans Health Administration (VHA) datasets. Bisphosphonate change behaviors were characterized using pharmacy refill records. Patients' baseline disease severity was characterized based on age, T-score, and prior fracture. Cox Proportional Hazard analysis was used to evaluate characteristics associated with discontinuation and the relationship between change behaviors and fracture outcomes. Generalized estimating equations were used to evaluate the relationship between change behaviors and cost outcomes.

RESULTS

A total of 35,650 patients met eligibility criteria. Over 6800 patients (19.1%) were non-switchers. The remaining patients were in the change cohort; at least half displayed more than one change behavior over time. A strong, significant predictor of discontinuation was ≥5 healthcare visits in the prior year (11-23% more likely to discontinue), and discontinuation risk decreased with increasing age. No change behaviors were associated with increased fracture risk. Total costs were significantly higher in patients with change behaviors (4.7-19.7% higher). Change-behavior patients mostly had significantly lower osteoporosis-related costs than non-switchers (22%-118% lower).

CONCLUSIONS

Most bisphosphonate patients discontinue treatment at some point, which did not significantly increase the risk of fracture in this majority non-high risk population. Bisphosphonate change behaviors were associated with significantly lower osteoporosis costs, but significantly higher total costs.

Outcome of glucose homeostasis in patients with glucocorticoid-induced osteoporosis undergoing treatment with bone active-drugs

Over the last few years, there has been experimental evidence for the existence of cross-talking between bone remodeling and glucose metabolism. Whether this experimental model can be translated to humans is still debated, and it is also unclear whether the modulation of bone turnover by anti-osteoporotic drugs may lead to changes in glucose metabolism. The aim of this 12-month prospective study was to investigate whether treatment of glucocorticoid-induced osteoporosis (GIO) with bipshosphonates or teriparatide may influence serum glycated hemoglobin (HbA1c) and fasting plasma glucose. One-hundred-eleven patients (70 F, 41 M, median age 70, range: 55-89) chronically treated with glucocorticoids were evaluated for changes in serum HbA1c and fasting plasma glucose during treatment with bisphosphonates (45 cases) or teriparatide (33 cases) as compared to those occurring during treatment with calcium and vitamin D alone (33 cases). In patients treated with teriparatide, but not in those treated with bisphosphonates or calcium and vitamin D alone, a statistically significant (p=0.01) decrease in serum HbA1c was observed during the follow-up, the change being greater (p=0.01) in patients with diabetes as compared to those without diabetes. In most cases, the decrease of serum HbA1c was relatively limited and in some patients the improvement of glucose homeostasis was concomitant with implementation of anti-diabetic treatments. Fasting plasma glucose did not change significantly during either bisphosphonates or teriparatide treatments. In conclusion, currently used bone active drugs may produce limited effects on glucose metabolism in patients with GIO. Interestingly, the bone anabolic drug teriparatide was shown to be associated with some improvement in serum HbA1c in this clinical context.

The effects of spinal cord injury and exercise on bone mass: a literature review

INTRODUCTION

Bone loss is a common and often debilitating condition that accompanies spinal cord injury. Because bone loss after spinal cord injury is multifactorial, it can be difficult to assess and treat. This process becomes even more complex as secondary conditions associated with aging are introduced.

PURPOSE

There are two purposes of this literature review. The first is to summarize information concerning the mechanisms of bone loss and osteoporosis after spinal cord injury. The second is to summarize existing data concerning the effects of exercise on bone loss after spinal cord injury.

METHOD

Literature was reviewed concerning the bone loss process and the non-pharmacological treatment options for ameliorating bone loss after spinal cord injury.

RESULTS

(Part One) Osteoporosis is universal in persons with chronic complete spinal cord injury, which increases the risk of bone fracture. Bone loss after spinal cord injury is both sublesional and regional with the greatest areas of bone demineralization being in the sublesional trabecular laden areas of the distal and proximal epiphyses of the femur and tibia. (Part Two) While passive weight bearing of paralyzed lower extremities appears to be ineffective, stressing the bones through muscular contractions initiated by electrical stimulation (FES) have yielded positive results in some cases. The intensity, frequency, and duration of stress to the bones appear to be important determinants of improved bone parameters. Although further quantification of these components is needed, some generalized guidelines can be deduced from completed research. Intensities showing positive results have been loads of one to one and a half times body weight for FES exercise or having participants FES cycle at their highest power output. Safety precautions must be used to decrease risk of bone fracture. Generally, the frequency is effective with three or more weekly exercise sessions. Studies of duration suggest that several months to one or more years of FES are necessary.

DISCUSSION

In order to promote healthy and independent aging in patients with spinal cord injury, it is important to understand the processes, consequences and effective treatments involved with bone loss.

Validated risk rule using computerized data to identify males at high risk for fracture

Absolute risk assessment is now the preferred approach to guide osteoporosis treatment decisions. Data collected passively during routine healthcare operations can be used to develop discriminative absolute risk assessment rules in male veterans. These rules could be used to develop computerized clinical decision support tools that might improve fracture prevention.

INTRODUCTION

Absolute risk assessment is the preferred approach to guiding treatment decisions in osteoporosis. Current recommended risk stratification rules perform poorly in men, among whom osteoporosis is overlooked and undertreated. A potential solution lies in clinical decision support technology. The objective of this study was to determine whether data passively collected in routine healthcare operations could identify male veterans at highest risk with acceptable discrimination.

METHODS

Using administrative and clinical databases for male veterans ≥50 years old who sought care in 2005-2006, we created risk stratification rules for hip and any major fracture. We identified variables related to known or theoretical risk factors and created prognostic models using Cox regression. We validated the rules and estimated optimism. We created risk scores from hazards ratios and used them to predict fractures with logistic regression.

RESULTS

The predictive models had C-statistics of 0.81 for hip and 0.74 for any major fracture, suggesting good to acceptable discrimination. For hip fracture, the cut-point that maximized percentage classified correctly (accuracy) predicted 165 of 227 hip fractures (73%) and missed 62 (27%). All hip fractures in patients with prior fracture were identified and 67% in patients without. For any major fracture, the maximal-accuracy cut-point predicted 611 of 987 (62%) and missed 376 (38%); the rule predicted all 134 fractures in patients with prior fracture and 56% in patients without.

CONCLUSION

Data collected passively in routine healthcare operations can identify male veterans at highest risk for fracture with discrimination that exceeds that reported for other methods applied in men.

Quantitative ultrasound of the heel and fracture risk assessment: an updated meta-analysis

Meta-analysis of prospective studies shows that quantitative ultrasound of the heel using validated devices predicts risk of different types of fracture with similar performance across different devices and in elderly men and women. These predictions are independent of the risk estimates from hip DXA measures.

INTRODUCTION

Clinical utilisation of heel quantitative ultrasound (QUS) depends on its power to predict clinical fractures. This is particularly important in settings that have no access to DXA-derived bone density measurements. We aimed to assess the predictive power of heel QUS for fractures using a meta-analysis approach.

METHODS

We conducted an inverse variance random effects meta-analysis of prospective studies with heel QUS measures at baseline and fracture outcomes in their follow-up. Relative risks (RR) per standard deviation (SD) of different QUS parameters (broadband ultrasound attenuation [BUA], speed of sound [SOS], stiffness index [SI], and quantitative ultrasound index [QUI]) for various fracture outcomes (hip, vertebral, any clinical, any osteoporotic and major osteoporotic fractures) were reported based on study questions.

RESULTS

Twenty-one studies including 55,164 women and 13,742 men were included in the meta-analysis with a total follow-up of 279,124 person-years. All four QUS parameters were associated with risk of different fracture. For instance, RR of hip fracture for 1 SD decrease of BUA was 1.69 (95% CI 1.43-2.00), SOS was 1.96 (95% CI 1.64-2.34), SI was 2.26 (95%CI 1.71-2.99) and QUI was 1.99 (95% CI 1.49-2.67). There was marked heterogeneity among studies on hip and any clinical fractures but no evidence of publication bias amongst them. Validated devices from different manufacturers predicted fracture risks with similar performance (meta-regression p values > 0.05 for difference of devices). QUS measures predicted fracture with a similar performance in men and women. Meta-analysis of studies with QUS measures adjusted for hip BMD showed a significant and independent association with fracture risk (RR/SD for BUA = 1.34 [95%CI 1.22-1.49]).

CONCLUSIONS

This study confirms that heel QUS, using validated devices, predicts risk of different fracture outcomes in elderly men and women. Further research is needed for more widespread utilisation of the heel QUS in clinical settings across the world.

Systems-based approaches to osteoporosis and fracture care: policy and research recommendations from the workgroups

Participants in the conference selected to attend two different working group sessions. The working groups discussed different perspectives of system-based approaches to osteoporosis and fracture care. The group on postfracture case management recommended that nurse case managers be used to improve communication among patients, orthopaedic surgeons, and those providing ongoing clinical care. The hospital working group discussed the impact of and barriers to improved postfracture management in the hospital setting. The health systems group emphasized the difference between a closed system in which long-term benefits of interventions were more likely to be appreciated than in fee for service systems. The health information technology group discussed the advantages and challenges of electronic health records. The working group on consumer and provider education discussed interventions for both primary and secondary prevention of fractures. Recommendations were produced by most groups for improving postfracture care.

Glucocorticoid-induced osteoporosis in men

Osteoporosis and fractures are a common consequence of glucocorticoid therapy for inflammatory disorders. Men fracture approximately 10 yr later in life than women and receive less attention as regards osteoporosis risk, including in glucocorticoid-induced osteoporosis (GIOP). In addition, while men are less likely to have certain rheumatologic disorders often treated with glucocorticoids, men are more likely to have chronic obstructive pulmonary disease, inflammatory bowel disease, and organ transplantation as reasons for use of oral glucocorticoids. Attempts to improve recognition of GIOP in general have not been successful, and since men are considered less at risk for osteoporosis in general, attention to men with GIOP is even less. Evaluation of GIOP is similar in men and women, and most modern treatment studies of GIOP have included men. Thus, alendronate, risedronate, and zoledronic acid are Food and Drug Administration (FDA)-approved bisphosphonates for GIOP in men. Teriparatide is also FDA-approved for GIOP. In one 36-month trial of teriparatide vs alendronate for GIOP in men and women, the anabolic agent led to a greater increase in bone density and was associated with a lower incidence of morphologic vertebral fractures. Thus, while good management is available for GIOP, recognition of men at risk is the most important step in improving outcomes.

Osteoporosis in men: the value of laboratory testing

Evaluation of 234 men referred for osteoporosis found many with undiagnosed secondary causes and multiple unrecognized risk factors.

INTRODUCTION

Studies in women with postmenopausal osteoporosis suggest that many have unrecognized disorders affecting bone. Men are considered more likely to have underlying, possibly correctable causes. We studied the prevalence of risk factors, secondary causes, and laboratory abnormalities in men with and without previously known causes for osteoporosis.

METHODS

We reviewed the charts of 234 men with osteoporosis diagnosed by bone mineral density testing. In addition to screening chemistries, 25-hydroxyvitamin D, testosterone, luteinizing hormone, follicle-stimulating hormone, thyroid-stimulating hormone, and spot urinary calcium-to-creatinine ratio were measured.

RESULTS

The mean age was 70.6 years and mean weight was 76.4 kg. The mean T-score for spine, femoral neck, and forearm was -2.2, -2.4, and -2.3, respectively. Evaluation revealed secondary osteoporosis in 75% overall including hypogonadism, vitamin D deficiency, hypercalciuria, subclinical hyperthyroidism, and hyperparathyroidism. In those men with known secondary osteoporosis at the time of dual energy X-ray absorptiometry testing, additional diagnoses were found in just over half. Vitamin D deficiency and insufficiency were very common, and other common risk factors for osteoporosis included age >65, current smoking, and prior fracture. Half of the subjects had ≥ 4 risk factors.

CONCLUSION

Evaluation revealed a specific cause in about half of men thought to have primary osteoporosis. Among men with known secondary osteoporosis, additional risk factors and secondary causes were frequently identified. In conclusion, a relatively modest evaluation of men with osteoporosis will often provide useful information.

Treatment thresholds for osteoporosis in men on androgen deprivation therapy: T-score versus FRAX

Men treated by androgen deprivation therapy (ADT) for localized prostate cancer are at risk for fracture, but it is not known which men require pharmacologic treatment. We found that 33% of men on ADT had osteoporosis of spine, hip, or forearm by dual-energy X-ray absorptiometry (DXA), thus requiring treatment. Using the new fracture prediction algorithm (FRAX) tool with corrected femoral neck T-score identified only 17% requiring treatment, and, if calculated without femoral neck, 54% were identified to need treatment.

INTRODUCTION

Men treated with androgen deprivation therapy (ADT) for prostate carcinoma live long enough to fracture. A new fracture prediction method, FRAX, is based on femoral neck DXA plus risk factors. Thus, DXA or FRAX could determine which men should receive osteoporosis therapy.

METHODS

Of 115 men undergoing ADT referred for DXA testing, those with bone mineral density (BMD) in spine, hip, or forearm of >or=2.5 standard deviations below a normal male ethnicity-adjusted mean were considered treatment candidates. Using FRAX with and without femoral neck BMD, men were treatment candidates if the 10-year hip fracture risk was >or=3% or the major osteoporotic fracture risk was >or=20%.

RESULTS

The men averaged 77 years old; 58% were African-American, and 14.8% were current smokers. Mean femoral neck T-score was -1.4. Using DXA, 38 (33%) men would need treatment. When FRAX was calculated including the femoral neck T-score, only 20 men met criteria for treatment. However, when FRAX was calculated without the T-score, 62 men met criteria for treatment. Overlap among the groups was surprisingly modest.

CONCLUSIONS

DXA and FRAX identify different ADT men for treatment.

An evaluation of osteoporosis screening tools for the osteoporotic fractures in men (MrOS) study

No large-scale evaluations of osteoporosis screening tools have been done in men. OST and MOST were examined among 4658 US Caucasian and 1914 Hong Kong Chinese men. Both tools have high negative predictive values, accurately screening out men with low risk, and saving a third of DXA tests.

INTRODUCTION

Prior investigations have studied the performance of osteoporosis screening tools in women, but no large-scale evaluations have been done in men.

METHODS

This study examines the performance of the Osteoporosis Self-assessment Tool (OST), the Male Osteoporosis Screening Tool (MOST), quantitative ultrasound index (QUI), and body weight as screening tools. Osteoporosis was defined by a dual-energy X-ray absorptiometry (DXA) measured bone mineral density (BMD) T-score < or =-2.5. Four thousand six hundred and fifty-eight US Caucasian and 1914 Hong Kong Chinese men, aged > or =65 years and community-dwelling, were included in the analysis. Receiver operating characteristic (ROC) analysis was used to compare the area under the ROC curve (AUC) between different screening tools.

RESULTS

MOST had a significantly larger AUC (> or =0.8) than OST, QUI, and body weight in detecting osteoporosis. Using the second tertile as cutoff, OST and MOST yielded sensitivities of around 90% and negative predictive values (NPVs) of >97%, accurately screening out Caucasian and Chinese men with low risk of osteoporosis.

CONCLUSIONS

OST and MOST can effectively rule out osteoporosis for both Caucasian and Chinese men, and compared to referring men 65 years and older for BMD DXA testing, they save a third of DXA resources.

Association of erosive hand osteoarthritis with a single nucleotide polymorphism on the gene encoding interleukin-1 beta

OBJECTIVE

Certain forms of primary osteoarthritis (OA), particularly those affecting hand joints, have a genetic component. Recent studies have shown suggestive evidence that hand and knee OA are linked with the interleukin-1 (IL-1) region on human chromosome 2q. This study was undertaken to assess the association of primary OA of the hand (hand OA) with IL-1 region markers.

METHODS

Sixty-eight US Caucasoid cases and 51 US Caucasoid controls aged 60 years or older were recruited from the Mid-Atlantic region of the United States. Hand OA was classified by American College of Rheumatology (ACR) Clinical Criteria, and cases were subjected to radiographic examination for subgrouping. Genotyping was done for seven previously described single nucleotide polymorphisms (SNPs) of genes for IL-1alpha (encoded by IL1A), IL-1beta (IL1B), and the IL-1 receptor antagonist (IL1RN), as well as an IL1RN variable number of tandem repeat (VNTR) marker. Six microsatellite markers on other chromosomes (null loci) were also typed.

RESULTS

The IL1B 5810 G>A SNP genotypes marker were not in Hardy-Weinberg equilibrium (p<0.05 in both non-erosive and erosive hand OA subgroups). Statistically significant association with the IL1B 5810 AA genotype was found in the erosive hand OA subgroup (relative risk 3.8, p=0.007). This IL1B 5810 AA genotype association was also significant between erosive and non-erosive hand OA subjects (relative risk 4.01, p=0.008). As expected, significant linkage disequilibrium was present between IL1B 5810 SNP and IL1A (-)889 SNP, other IL1B SNPs, and the nearest IL1RN SNP examined. The IL1B 5810A allele occurs most frequently on haplotypes with the SNP alleles IL1B 1423C, IL1B 1903T, IL1B 5887C, and IL1A (-)889C. Genotypes at null loci failed to show evidence suggesting population stratification that might account for spurious association.

CONCLUSION

Statistical evidence shows association between erosive hand OA and a genomic region containing the IL1B 5810 SNP in a US Caucasoid population. This supports a potential role for IL-1 in the pathogenesis of a severe phenotype of hand OA.

Long-term survival of allogeneic donor cell-derived corneal epithelium in limbal deficient rabbits

PURPOSE

To investigate the capability of cultivated allogeneic epithelial stem cells to restore a functional ocular surface in a limbal deficient cornea; to verify the long term survival of epithelial allograft; and to examine the host immune response to heterologous cell transplant in a rabbit model.

METHODS

Limbal deficiency was established by performing limbectomy on rabbits (n = 100). Corneal epithelial stem cells were obtained from the limbus and replicated in vitro without a supporting layer. The cell (3 x 10(5)) suspension was then transplanted via topical application as eye drops. Animals were divided into allograft, autograft, and control groups. Females were used as recipients and males as donors for the allograft. Corneas were collected at 7, 14, 21, 40 days as well as 2, 3, 7 and 8 months after cell transplantation. Experimental corneas were evaluated by histology, immunofluorescence, immunohistochemistry and Y chromosome analysis.

RESULTS

A well-differentiated corneal epithelium was recognized at 14 to 40 days after cell transfer overlying an infiltrated corneal stroma. Corneal re-epitheliazation was confirmed in 31 of 36 allograft corneas. No significant immune rejection was noted. Stromal abnormality caused by previous limbal deficiency was mostly resolved three months after the regeneration of corneal epithelium.

CONCLUSIONS

Transplanted corneal epithelial stem cells were able to differentiate into normal corneal epithelium in vivo without the use of membrane scaffolding. This non-autologous donor cell-derived corneal epithelium survived up to 8 months without immunosuppression and was able to reverse the stromal scarring. Thus, cultivated epithelial stem cells have great potential as an alternative to multiple-surgical procedures in the treatment of limbal deficiency states.

Utility of heel ultrasound bone density in men

In women, heel ultrasound (US) bone mineral density (BMD) has been shown to predict fracture risk, but the usefulness of this screening tool in men is not known. We measured the heel quantitative ultrasound index (QUI( in a convenience sample 185 of men (136 Caucasian, 1 Asian, and 48 African-American) with an average age of 63 yr (range of 25-85) undergoing BMD of the spine and hip by dual X-ray absorptiometry (DXA) to determine whether the heel measurement could predict central BMD. The average DXA T-score was -0.97, -1.20, and -1.61 for the spine, total hip, and femoral neck, respectively. The mean heel US BMD T-score (using the only available T-score, which was defined for Caucasian postmenopausal women) was -0.92. There were significant correlations among the various DXA measurements and the heel US BMD T-score (r = 0.373-0.483, p < 0.001). We defined arbitrarily osteopenia as a spine, total hip, or femoral neck T-score by DXA of < -1.5. We also made two different arbitrary definitions of osteoporosis by DXA: < -2.0 and < -2.5. Using these numbers as disease definitions, we determined the specificity, sensitivity, as well as positive and negative predictive values of using the heel US T-score to predict osteopenia or osteoporosis. Using various cutoffs for the heel T-score, we found that increasing the cutoff toward 0 increased the sensitivity but lowered the specificity. No cutoff was found that provided both good sensitivity and specificity. By analyzing the men by ethnic and age groups, we found that the best set of receiver operating characteristic (ROC) curves was derived from data using heel US to predict osteopenia and osteoporosis in men younger than age 65, although the areas under the ROC curve were approx 0.8. In conclusion, despite a strong correlation between the heel QUI and the spine and hip BMD by DXA, no heel T-score could predict osteopenia or osteoporosis with satisfactory sensitivity and specificity. It is possible that the use of risk factor assessment plus heel QUI might have better predictive value, and further studies are needed to determine whether heel QUI or other US determination is an independent risk factor for fracture in men.

Leptin responses to glucose infusions in obesity-prone rats

The secretion of leptin is dually regulated. In fasting animals, plasma leptin concentrations reflect body fat stores, whereas the incremental leptin response to fasting or refeeding most likely reflects insulin-mediated energy flux and metabolism within adipocytes. Impaired secretion of leptin in either pathway could result in obesity. We therefore measured plasma leptin concentrations in fasted animals and plasma leptin concentrations after an intravenous glucose infusion in a rat model of obesity. Young Sprague-Dawley (S-D) and Fischer 344 (F344) rats had similar percent body fat and fasting glucose and fasting leptin concentrations. However, F344 animals had higher insulin concentrations and leptin responses to intravenous glucose than did the S-D animals. The animals were then fed a control or high-fat diet for 6 wk. High-fat fed animals gained more weight and body fat than did the control fed animals. Control and high-fat fed F344 animals gained approximately 40% (P < 0.0001) more weight and >100% (P < 0.01) more body fat than did the S-D animals. Fasting leptin concentrations and leptin concentrations after intravenous glucose infusions and feeding were more than double (P < 0.05) in F344 animals compared with S-D animals. Whether an animal is fed a control or high-fat diet had little effect on the leptin response to intravenous glucose. In conclusion, young, lean F344 animals, before the onset of obesity, demonstrated a greater acute leptin response to intravenous glucose than similarly lean S-D animals. After a 6-wk diet, F344 animals had a greater percent increase in body weight and insulin resistance and exhibited higher fasting leptin concentrations and a greater absolute leptin response to intravenous glucose compared with the S-D animals. The chronic diet (control or high fat) had little impact on the acute leptin response to intravenous glucose. F344 animals exhibit leptin resistance in young, lean animals and after aging and fat accumulation.

Sex steroids and osteoporosis. The role of estrogens and androgens

Osteoporosis (low bone mass) depends on the peak bone mass attained and bone loss after the peak. Sex steroids (estrogens and androgens) have an impact on both processes. In this article the roles and mechanisms of estrogens and androgens are discussed in relation to clinical osteoporosis. Other hormones and hormone-like drugs, such as raloxifene, may be used to mimic the effects of natural sex steroids.

Dual regulation of leptin secretion: intracellular energy and calcium dependence of regulated pathway

Rodent leptin is secreted by adipocytes and acutely regulates appetite and chronically regulates body weight. Mechanisms for leptin secretion in cultured adipocytes were investigated. Acutely, energy-producing substrates stimulated leptin secretion about twofold. Biologically inert carbohydrates failed to stimulate leptin secretion, and depletion of intracellular energy inhibited leptin release. There appears to be a correlation between intracellular ATP concentration and the rate of leptin secretion. Insulin increased leptin secretion by an additional 25%. Acute leptin secretion is calcium dependent. When incubated in the absence of calcium or in the presence of intracellular calcium chelators, glucose plus insulin failed to stimulate leptin secretion. In contrast, basal leptin secretion is secreted spontaneously and is calcium independent. Adipocytes from fatter animals secrete more leptin, even in the absence of calcium, compared with cells from thinner animals. Acute stimulus-secretion coupling mechanisms were then investigated. The potassium channel activator diazoxide and the nonspecific calcium channel blockers nickel and cadmium inhibited acute leptin secretion. These studies demonstrate that intracellular energy production is important for acute leptin secretion and that potassium and calcium flux may play roles in coupling intracellular energy production to leptin secretion.

The Veterans Affairs Implantable Insulin Pump Study: effect on cardiovascular risk factors

OBJECTIVE

To determine whether implantable insulin pump (IIP) and multiple-dose insulin (MDI) therapy have different effects on cardiovascular risk factors in insulin-requiring patients with type 2 diabetes.

RESEARCH DESIGN AND METHODS

A randomized clinical trial was conducted at seven Veterans Affairs medical centers in 121 male patients with type 2 diabetes between the ages of 40 and 69 years receiving at least one injection of insulin per day and with HbA1c, levels of > or =8% at baseline. Weights, blood pressures, insulin use, and glucose monitoring data were obtained at each visit. Lipid levels were obtained at 0, 4, 8, and 12 months, and free and total insulin levels were obtained at 0, 6, and 12 months. All medications being taken were recorded at each visit.

RESULTS

No difference in absolute blood pressure, neither systolic nor diastolic, was seen between patients receiving MDI or IIP therapy, but significantly more MDI patients required anti-hypertensive medications. When blood pressure was modeled against weight and time, IIP therapy was significantly better than MDI therapy for systolic blood pressure in patients with BMI <33 and for diastolic blood pressure in patients with BMI >34 kg/m2. Total cholesterol levels decreased in the overall sample, but IIP patients exhibited significantly higher levels than MDI patients. Triglyceride levels increased over time for both groups, with IIP patients having significantly higher levels than patients in the MDI group. BMI was a significant predictor of, and inversely proportional to, HDL cholesterol level. No difference in lipid-lowering drug therapy was seen between the two groups. Free insulin and insulin antibodies tended to decrease in the IIP group as compared with the MDI group. C-peptide levels decreased in both groups.

CONCLUSIONS

IIP therapy in insulin-requiring patients with type 2 diabetes has advantages over MDI therapy in decreasing the requirement for antihypertensive therapy and for decreasing total and free insulin and insulin antibodies. Both therapies reduce total cholesterol and C-peptide levels.

Association between serum insulin growth factor-I (IGF-I) and a simple sequence repeat in IGF-I gene: implications for genetic studies of bone mineral density

We recently demonstrated that insulin growth factor-I (IGF-I) cosegregates with bone mineral density (BMD) in progenitor crosses of two inbred strains of mice. Additionally, we reported that men with idiopathic osteoporosis (IOM) have low serum IGF-I levels, which can be related to BMD and bone turnover. In this study, we considered the possibility that serum IGF-I levels are influenced by molecular genetic variation in the IGF-I structural gene, and that a polymorphic microsatellite (CA repeat) in this locus can be used as a genetic marker for such comparisons. We studied 171 men and women, classified according to the trial in which they were participating. First, in 25 Caucasian men with IOM we noted a very high frequency (64%) of homozygosity for the most common allele (192 bp) in a dinucleotide repeat 1 kb upstream from the transcription start site of the IGF-I gene. This compared with a frequency of only 32% in healthy populations (both men and women) (P < 0.004). Next, we determined that for 116 healthy Caucasian men and women the 192/192 genotype was associated with lower serum IGF-I levels than all other genotypes (192/192: 129 +/- 7 ng/mL vs. others: 154 +/- 7 ng/mL, P = 0.03). We also noted that subjects possessing one 194-bp allele exhibited serum IGF-I levels 25% higher than those homozygous for 192 bp (192/192), (P < 0.005) even after correction for age and sex. Similarly, for men with the 192/192 genotype, serum IGF-I concentrations were lower than any other genotype (145 +/- 10 ng/mL vs. 183 +/- 9 ng/ml P < 0.02). In conclusion, low serum IGF-I levels found in men with IOM are associated with homozygosity for a specific allele of the IGF-I microsatellite (192/192), and individual variation in serum IGF-I levels is influenced by genetic factors and may be specifically influenced by variation at the IGF-I structural locus. Further family and pedigree studies are needed to characterize the relationship of bone mass acquisition to the IGF-I genotype.

Relative effects of prolactin excess and estrogen deficiency on bone in rats

Humans with prolactinoma are at risk for osteoporosis. The relative contributions of hyperprolactinemia-induced hypogonadism and the prolactin (PRL) excess per se have been unclear from clinical studies. To determine the effects of PRL excess, two models of chronic hyperprolactinemia were used. In one, mild hyperprolactinemia was produced in rats bearing extra anterior pituitary glands under the kidney capsule. Severe hyperprolactinemia was produced by subcutaneously transplanting the PRL-secreting MMQ tumor into other rats. To control for estrogen deficiency, the rats were ovariectomized. In some experiments, estrogen replacement was provided. Urinary calcium excretion was increased in hyperprolactinemic rats compared with controls, regardless of severity of PRL excess and estrogen status. This suggested that PRL excess itself had some effect on calcium balance. More importantly, however, the spinal bone mineral density (BMD; measured by dual-energy x-ray densitometry) of mildly hyperprolactinemic ovariectomized rats was the same as control ovariectomized rats. Similarly, tibial dry weight and ash weight were affected by the estrogen status, but not by the severe PRL excess of the tumor-implanted rats. Thus, despite the evidence for an increase in urinary calcium excretion in hyperprolactinemic rats, estrogen deficiency is much more important in determining bone mineral. Therefore, the present data indicate that the osteoporosis of hyperprolactinemia is likely due to PRL-induced hypogonadism, rather than a direct effect of PRL on calcium homeostatis.

Is malnutrition overdiagnosed in older hospitalized patients? Association between the soluble interleukin-2 receptor and serum markers of malnutrition

BACKGROUND

Many researchers have speculated that markers of malnutrition such as albumin, prealbumin, cholesterol, and transferrin are influenced by inflammation. The mechanism of this interaction has not been well understood.

METHODS

This was a prospective cross-sectional study. We evaluated 72 male patients older than 60 years admitted to a geriatric rehabilitation unit. Subjects with severe hepatic or renal diseases were excluded. We measured body mass index, caloric intake, serum albumin, prealbumin, cholesterol, transferrin, hemoglobin, and total lymphocyte count. To detect inflammation, we measured C-reactive protein, Westergren sedimentation rate, fibrinogen, and cytokines including tumor necrosis factor-alpha (TNF-alpha), interleukin-1 beta (IL-1 beta), IL-6, IL-2, and the soluble IL-2 receptor.

RESULTS

Soluble IL-2 receptor was negatively associated with albumin (r = -.479, p < .0001), prealbumin (r = -.520, p = < .0001), cholesterol (r = -.487, p = .0001), transferrin (r = -.455, p = .0002), and hemoglobin (r = -.371, p = .002). TNF-alpha, IL-1 beta, IL-6, and IL-2 were not associated with these measures.

CONCLUSIONS

Inflammation increases the incidence of hypoalbuminemia and hypocholesterolemia, potentially leading to overdiagnosis of malnutrition. We suggest that albumin, cholesterol, prealbumin, and transferrin be used with caution when assessing the nutritional status of older hospitalized patients. In the future, soluble IL-2 receptor levels might be used to correct for the impact of inflammation on these markers of malnutrition.

Increased bone mineral density in a man with known compression fractures

A 70-yr-old man was referred for bone mineral density because of a history of vertebral and hip fracture. His past history included prednisone-treated rheumatoid arthritis and stroke resulting in hemiparesis and expressive aphasia. He had received injections for back pain at another hospital. The overall spine T-score was +3.40 with L3 at +10.92. The overall hip T-score was -1.09 with the femoral neck at -1.75 and Ward's triangle at -2.94. Radiographs of the spine revealed increased densities of L2-4. The patient's wife provided information the aphasic patient could not. The back injections were part of a vertebroplasty for stabilization. The patient had such great pain relief that he ambulated too soon, fell, and suffered a right hip fracture. Injection of polymethylmethyacrylate is a new addition to the treatment of spinal osteoporosis. The case demonstrates the importance of acquiring a complete medical history.

The soluble interleukin-2 receptor predicts mortality in older hospitalized men

BACKGROUND

There is an inverse relationship between the soluble interleukin-2 receptor (sIL-2R) and serum albumin, cholesterol, transferrin, prealbumin, and hemoglobin. Inasmuch as low serum albumin and cholesterol have been associated with excess mortality, we hypothesized that elevated sIL-2R would predict mortality in older adults.

OBJECTIVE

To determine if elevated sIL-2R predicts mortality in patients on a geriatric rehabilitation unit.

DESIGN

Prospective cohort.

SETTING

University-affiliated VA medical center.

PARTICIPANTS

Seventy-two male patients aged greater than 60 years admitted to a geriatric rehabilitation unit. Patients with severe hepatic or renal disease were excluded.

MEASUREMENTS

We measured serum albumin, prealbumin, cholesterol, transferrin, hemoglobin, body mass index (BMI), C-reactive protein (CRP), and sIL-2R upon admission. Subjects were followed for 1 year.

RESULTS

Low serum albumin, prealbumin, and hemoglobin and high sIL-2R and CRP predicted 1-year mortality on univariate analysis. When these predictors were included as covariates in a Cox regression model, only sIL-2R was a significant independent predictor of mortality (P = .043). Multiple linear regression with the above covariates revealed that only sIL-2R predicted time to death at (P = .003).

CONCLUSIONS

High sIL-2R and CRP and low albumin, prealbumin, and hemoglobin predicted mortality using univariate analysis on a rehabilitation unit. However, with multivariate analysis, sIL-2R was the sole predictor of mortality.

Modulation of the inflammatory effects of inhaled ozone in rats by subcutaneous prolactin-secreting, pituitary-derived tumors

Rats are more sensitive to ozone-induced pulmonary inflammation and damage during late pregnancy and throughout lactation than in pre- or early pregnancy or postlactation. This window of sensitivity coincides with a period of elevated levels of pituitary-derived prolactin or placental lactogen. In this study, we investigated the hypothesis that prolactin exerts an enhancing effect on ozone-induced pulmonary inflammation and damage, thus presenting a plausible explanation for the sensitivity profile observed in rats. Hyperprolactinemia was achieved by using rats with subcutaneous tumors that were derived from the MMQ tumor model previously described by Adler and co-workers (Adler, R. A., Krieg, R. J., Farrell, M. E., Deiss, W. P., and MacLeod, R. M., Metabolism 40, 286-291, 1991). A variant of the MMQ tumor, the MMQr tumor, which appeared spontaneously from a single passage of MMQ tumor tissue, produced elevated levels of corticosterone in addition to high levels of prolactin. These two subcutaneous tumors had markedly different effects on adrenal, thymus, and spleen weights because of the different hormonal milieu they generated. There was also a significant difference between MMQ- and MMQr-bearing rats in their inflammatory response to acute ozone exposure as assessed by polymorphonuclear leukocytes (PMNs) in the airways. Rats with MMQ tumors were not significantly different from non-tumor-bearing controls in their baseline level of airway PMNs and PMN inflammation following ozone exposure, whereas MMQr-bearing rats had significantly elevated baseline PMNs in their airways and a greater PMN response to inhaled ozone. The hormonal milieu and elevated PMNs in the airways of both unexposed and ozone-exposed rats with MMQr tumors were similar to levels observed in lactating rats. The role of corticosterone in pulmonary inflammation in this model was investigated further by treating MMQ tumor-bearing rats with dexamethasone. Dexamethasone was effective in producing changes in organ weights similar to those observed in MMQr rats, but did not elicit higher airway PMN concentrations in unexposed rats as observed in the MMQr rats. We conclude that in this animal model prolactin did not significantly elevate airway PMN inflammation induced by ozone, and supplementation with exogenous glucocorticoid did not duplicate the endogenous airway PMNs numbers observed in MMQr-bearing rats or lactating rats.

Implantable insulin pump vs multiple-dose insulin for non-insulin-dependent diabetes mellitus: a randomized clinical trial. Department of Veterans Affairs Implantable Insulin Pump Study Group

OBJECTIVE

To determine whether implantable insulin pump (IIP) therapy and multiple daily insulin (MDI) injections could equally attain improved blood glucose control, and to compare the 2 treatments with respect to reducing daily blood glucose fluctuations, reducing serious hypoglycemic insulin reactions, and improving patients' quality of life.

DESIGN

Randomized clinical trial.

SETTING

Seven Veterans Affairs medical centers.

PATIENTS

One hundred twenty-one male type II diabetic patients between the ages of 40 and 69 years, receiving at least 1 injection of insulin per day and having hemoglobin A1c (HbA1c) levels of 8% or above.

INTERVENTION

Intensive therapy (IIP or MDI) for 1 year.

MAIN OUTCOME MEASURES

Hemoglobin A1c and blood glucose levels.

RESULTS

Blood glucose levels declined to 7.96+/-1.08 mmol/L (143.4+/-19.5 mg/dL) and 8.30+/-1.52 mmol/L (149.6+/-27.4 mg/dL) (mean +/- SD) for IIP and MDI, respectively (P=.57). Hemoglobin A1c levels improved in both groups (time effect P<.001), to means of 7.54%+/-0.83% (MDI) vs 7.34%+/-0.79% (IIP). IIP reduced blood glucose fluctuations compared with MDI (P<.001), and reduced the incidence of mild clinical hypoglycemia by 68% (P<.001); IIP also eliminated the weight gain associated with MDI therapy and yielded better overall quality-of-life (P=.03) and impact-of-disease subscale scores (P=.05). Adverse events included 25% of subjects with episodes of insulin underdelivery due to microprecipitates of insulin within the pump.

CONCLUSIONS

Intensive insulin therapy with IIP and MDI is effective in controlling non-insulin-dependent diabetes mellitus. IIP has significant advantages in reducing glycemic variability, clinical hypoglycemia, and weight gain, while improving aspects of quality of life.

Glucocorticoids and osteoporosis

In summary, patients who will remain on glucocorticoids for more than a few weeks are clearly at risk for osteoporosis. A list of therapeutic strategies is provided in Table 2. While our therapy remains inadequate at this time, newer agents are on the horizon. In the near future, it may be possible to recommend specific agents for prevention of osteoporosis. Until longer term studies are completed, careful attention to the method of glucocorticoid administration, maintenance of exercise, supplementation with Vitamin D if needed, and adequate calcium intake are the mainstays of prevention. Possible treatments in the near future may include newer bisphosphonates, growth factors, and newer forms of calcitonin.

Anti-proliferative effects of deflazacort on Nb2 cells as quantitated by formazan production

Prolactin and other lactogenic hormones are mitogenic for the rat T-cell lymphoma line, Nb2. Glucocorticoids have antiproliferative effects on these cells. A limiting feature of experiments utilizing the Nb2 line is their labor-intensive nature. We therefore adapted the commonly used MTT dye proliferation assay for the Nb2 cell line. While rPRL, hPRL, oPRL, hGH, bPL, and to a lesser extent bPRL stimulated the Nb2 cells, hormones without lactogenic activity, rGH and oGH did not. Human serum and rat sera from animals bearing a PRL-secreting tumor stimulated the Nb2 cells in parallel to standards. Glucocorticoids had anti-proliferative effects on Nb2 cells in the presence of half-maximal or maximal PRL doses, as measured by the MTT proliferation assay. It has been claimed that an oxazoline steroid, deflazacort, has anti-inflammatory effects in clinical studies with fewer of the deleterious side-effects common to glucocorticoids. We therefore compared the in vitro anti-proliferative effects of deflazacort with other glucocorticoids. Deflazacort's negative effect on Nb2 cell proliferation was similar to that of cortisol and prednisolone and less than that of dexamethasone. We conclude that the MTT proliferation assay can be used to study both mitogenic and anti-proliferative substances in Nb2 cells. In addition we found that deflazacort acts similarly in vitro to other glucocorticoids.

Testosterone administration increases insulin-like growth factor-I levels in normal men

Although testosterone (T) administration can increase insulin-like growth factor-I (IGF-I) when administered to hypogonadal men, no studies have examined whether this occurs in normal men. The present study was undertaken to determine if an increase in IGF-I may be part of the anabolic effect of androgens. We enrolled 11 normal men in a randomized, double-blinded cross-over study. Subjects were assigned to receive either T enanthate (TE) (300 mg im, each week) or nandrolone (ND) decanoate (300 mg im, each week) for 6 weeks. After a washout period subjects were administered the alternate treatment. Pre- and posttreatment serum was analyzed for IGF-I by RIA after acid-ethanol extraction. Results expressed as mean +/- SEM (Table 1). IGF-binding protein-3 was measured by RIA and was unchanged in the TE treatment and decreased significantly after ND treatment. Although GH levels were not significantly different after either TE or ND treatment, they tended to increase after TE treatment (1.23 +/- 0.28 ng/mL vs. 3.3 +/- 1.03 ng/mL) but remained unchanged after ND treatment (1.68 +/- 0.68 ng/mL vs. 1.89 +/- 0.64 ng/mL). Serum total T levels increased 32 +/- 0.05 nmol/L in the TE-treated men, but fell by 7 +/- 0.02 nmol/L in the ND-treated men (P < 0.0001). Serum estradiol levels rose by 193.04 +/- 19.82 pmol/L in the TE-treated men although falling by 50.65 +/- 34.50 pmol/L in the ND-treated men (P < 0.0002). These data indicate that when normal men are given TE, serum IGF-I levels increase after 6 weeks of treatment. Treatment with ND did not change serum levels of IGF-I but did decrease the level of the major serum IGF-BP and therefore the level of bioavailable IGF-I may be increased in the ND group.

Longitudinal changes in lumbar bone density among thyrotoxic patients after attainment of euthyroidism

Hyperthyroidism increases bone turnover, which, in turn, may lead to bone loss from the spine and hip. Treatment of thyrotoxicosis may restore bone mass, but there are few long term prospective studies. We examined lumbar bone mineral density (BMD) in 21 subjects [11 with hyperthyroidism (HT) and 10 controls of similar age] by dual photon absorptiometry in 1986 and by dual energy x-ray densitometry in 1991. All 11 HT patients were successfully treated and remained euthyroid (mean TSH, 2.25 +/- 0.80 mU/L) for more than 3 yr. Lumbar BMD increased 11.03 +/- 2.38% (P < 0.001) in HT patients, but only 2.6 +/- 2.15% (P = 0.10) in control subjects. Among HT patients, the higher the T3 concentration during hyperthyroidism, the greater the subsequent increase in lumbar BMD (r = 0.72; P < 0.03). Age at treatment, in contrast, was not a significant predictor of eventual spinal bone mass. In conclusion, successful treatment of hyperthyroidism produced a significant increase in lumbar BMD. Hence, bone loss associated with thyrotoxicosis may not be permanent. Future work designed to examine the effect of thyroid hormone on skeletal homeostasis should include large scale longitudinal studies of both men and women.

Mild vitamin D deficiency and secondary hyperparathyroidism in nursing home patients receiving adequate dietary vitamin D

OBJECTIVE

To compare the vitamin D metabolite and nutritional status of institutionalized elderly males with a noninstitutionalized control group.

DESIGN

Case-control study.

SETTING

Veterans Administration Medical Center Nursing Home (NH) in Richmond, Virginia.

PATIENTS

Fifty-seven consecutive nursing home subjects were screened. After excluding blacks, those receiving anticonvulsants, glucocorticoids, or vitamin supplements, and those with liver or renal failure (creatinine greater than 1.5 mg/dL), 35 subjects were enrolled, and 22 completed the study. The noninstitutionalized control group (n = 18) consisted of consecutive volunteers, meeting the above criteria, from either a senior citizen group or a geriatric clinic.

MEASUREMENTS AND MAIN RESULTS

The serum 25-hydroxy-vitamin D level in the NH residents was significantly lower than in community dwellers (17.4 +/- 5.2 ng/mL vs 31.2 pg/mL +/- 8.0 ng/mL, P less than 0.0001). No significant difference was demonstrated in 1,25-dihydroxyvitamin D levels (36.5 pg/mL +/- 10.5 in NH residents vs 42.0 pg/mL +/- 11.1 in controls). In the NH group PTH levels were inversely correlated with 25 OHD levels (P less than 0.008) and positively correlated with length of stay in the NH (P less than 0.016). There was no significant seasonal variation in vitamin D metabolite levels in the NH group. In the NH patients, the mean dietary intake of vitamin D was 232 +/- 378 mg/day and of calories was 1811 +/- 447 kcal/day.

CONCLUSION

Despite apparently adequate calories, calcium, and vitamin D intake, hypovitaminosis D with compensatory PTH elevations occurs, regardless of season, in the nursing home population.

Normal food intake and growth in hyperprolactinemic rats

Normal lactation, a state of chronic hyperprolactinemia, is often accompanied by increased food intake. Two recent reports suggested that, in rats, prolactin (PRL) administration or chronic endogenous PRL excess led to increased food intake and growth. Similar methods of achieving augmented circulating levels of PRL in rats have been employed in our laboratory. Rats with extra anterior pituitary (AP) grafts under the kidney capsule have chronically elevated circulating PRL levels. However, in several experiments, weight gain, food intake, and fecal weight were the same in AP-grafted rats and in control muscle-grafted rats. In addition, the AP-grafted rat model was modified to demonstrate that PRL-induced increases in adrenal glucocorticoids and decreases in estrogens did not provoke alterations in eating behavior. Injection of homologous PRL for 8 days did not increase weight gain in normal or hypophysectomized rats. These data suggest that neither the chronic PRL excess caused by AP grafts nor the acute PRL excess caused by rat PRL injections increases food intake or weight gain.

Hypercalciuria in a new rat model of hyperprolactinemia

Hypercalciuria has been reported in rats with mild hyperprolactinemia due to implantation of anterior pituitary glands under the kidney capsule and in rats bearing transplantable tumors that secrete large amounts of prolactin (PRL) and growth hormone (GH). We studied Buffalo rats implanted subcutaneously with the new MMQ pituitary tumor line that secretes only PRL. Urinary calcium excretion increased as the tumors grew. Three weeks after tumor implantation in female rats, the urinary calcium excretion was 1.102 +/- 0.092 mg/100 g body weight (BW).24 hours compared with controls, 0.296 +/- 0.079, P less than .0005. Male tumor-bearing rats also had increased urinary calcium excretion compared with male controls. In tumor-bearing rats the urinary calcium excretion factored for urinary sodium excretion, dietary calcium intake, or urinary creatinine excretion was elevated. Urinary calcium excretion was correlated with serum PRL levels and with estimated tumor volume. Serum calcium, immunoassayable parathyroid hormone, and urinary cyclic adenosine monophosphate (cAMP) excretion were normal in the tumor-bearing rats. There was some evidence of loss of bone calcium in rats bearing the MMQ tumor, and serum levels of calcitonin were decreased. These results are similar to those found in anterior pituitary-grafted hypercalciuric rats. It is unlikely that parathyroid hormone (PTH) abnormalities are responsible for the hypercalciuria in the MMQ-bearing rats. The pituitary gland may have an effect on the distal renal tubule to decrease calcium reabsorption.

Characterization of a new animal model of chronic hyperprolactinemia

Animal models of chronic prolactin (PRL) excess have included rats bearing transplantable pituitary tumors that have produced other hypophyseal hormones in addition to PRL. We report characterization of a new model, the Buffalo rat implanted with the MMQ tumor, a line developed from the 7315a line. Rats implanted with the MMQ tumor have serum PRL levels that increase with time and correlate with the estimated volume of the subcutaneous tumor. When rats are killed 4 weeks after implantation, serum PRL levels are strikingly higher in tumor-bearing rats compared with controls (females, 2,723 +/- 266 v 192 +/- 46 ng/mL, P less than .0001; males, 1,637 +/- 213 v 99 +/- 11 ng/mL, P less than .0001). Serum PRL levels measured by the Nb2 lymphoma assay were higher than immunoassay measurements in both tumor-bearing and control Buffalo rats. Sephadex chromatography of serum from tumor-bearing rats showed that most of the PRL immunoreactivity co-eluted with 125I-rPRL. Neither serum growth hormone (GH) nor luteinizing hormone (LH) levels were different from controls in tumor-bearing rats. Female MMQ-bearing rats had lower estradiol levels. At death, the wet weights of adrenal glands, kidneys, and gonads were not affected by the presence of tumor. In contrast, tumor-bearing rats had increased spleen weight and histological evidence of white pulp hyperplasia. The Buffalo rat implanted with the PRL-only MMQ tumor is a promising new tool for the study of chronic hyperprolactinemia.

T lymphocyte surface antigen markers in osteoporosis

Two distinct syndromes of osteoporosis have been postulated: type I, which is characterized by accelerated bone loss occurring in women during the early postmenopausal period; and type II, an age-related process of bone loss affecting both men and women in and after the seventh decade. Recently there has been indirect evidence linking local products of the immune system with bone remodeling. We therefore studied peripheral blood profiles of specific lymphocyte phenotypes in women with type I osteoporosis and in older women and men with type II osteoporosis. The ratio of CD4-bearing (T helper) cells to CD8-bearing (T cytotoxic-suppressor) cells (CD4/CD8 ratio) was elevated in women with symptomatic type I disease. In addition there was a significant negative correlation (r = -0.62, P less than 0.001) between the CD4/CD8 ratio and the spinal bone mineral density measured by dual-photon absorptiometry. In contrast, older men with a history of fracture (hip or spine) had CD4/CD8 ratios similar to control men. The number of T cells bearing IL-2R or VLA-1 was not different between osteoporotic subjects and controls in either men or women. This study supports the concept that local products of the immune system may be directly or indirectly involved in the pathogenesis of type I osteoporosis.

Exercise patterns and trabecular bone density in college women

To assess the effects of physical activity patterns on trabecular bone density in college women, we studied three groups of nonsmoking eumenorrheic women with different (but chronic) exercise regimens. There were nine sedentary (SED) women exercising less than 1 h/week, nine women who performed aerobic (AER) exercise greater than 2.5 h/week, and nine women who supplemented aerobics with muscle-building activities (MB) for more than 1 h/week. Resting energy expenditure, calorie, protein, and calcium intake, total body weight, and body mass index were not statistically different among the three groups. AER and SED women had similar lumbar bone mineral density (BMD). MB women had significantly greater spinal bone density (p less than 0.007 versus SED, AER). IGF-1 (insulin-like growth factor) concentrations were greatest in MB (p less than 0.01), and hours muscle building per week correlated with IGF-1 (r = 0.86, p less than 0.03). For all 27 women (mean age 24.5 years), body mass index was the single best predictor of lumbar BMD (r = 0.42, p less than 0.03); hours in muscle-building exercise per week conferred an additive effect on lumbar BMD. This cross-sectional study of young women suggests chronic muscle-building exercises may augment lumbar bone mass. The additive effect of anaerobic exercise on bone density may be mediated by both local weight-bearing changes and possible systemic factors.

Growth hormone (GH) secretion in the pituitary-grafted male rat: in vivo effects of GH-releasing hormone and isoproterenol and in vitro release by individual somatotropes

Although the pituitary-grafted rat is a classic model of chronic PRL excess, the presence of somatotropes in grafted pituitary tissue indicates a potential for GH secretion. The current study was designed to investigate GH-releasing hormone (GRH)-induced GH secretion and beta-adrenergic inhibition of GH release in animals bearing ectopic pituitary tissue free from hypothalamic control. Positive findings with regard to these in vivo experiments led us to an initial determination of GH secretion by individual somatotropes from transplanted pituitary tissue. In litters of 10 30-day-old Fisher rats, 2 male animals received subcapsular renal grafts of 3 littermate pituitary glands each. Thirty-five days after grafting, 1 group received saline (SAL) followed by GRH, and the other received the beta-adrenergic agonist isoproterenol (ISO) followed by GRH. Blood samples were taken before and after SAL or ISO treatment, GRH was then infused, and sampling was continued. Plasma was assayed for GH and PRL, and the reverse hemolytic plaque assay was used to determine GH release by individual somatotropes from transplanted pituitary tissue. Plasma PRL was clearly elevated in pituitary-grafted compared to muscle-grafted animals, but there was no difference in either body weight gain or basal GH levels between the groups. As shown previously, ISO itself induced a brief release of GH due to its direct effect on the pituitary gland. The GH response to GRH was greater in pituitary-grafted animals than in muscle-grafted controls after both SAL and ISO. GRH-induced GH release was suppressed by ISO pretreatment in muscle-grafted animals, but not in pituitary-grafted animals. The reverse hemolytic plaque assay unequivocally showed that transplanted pituitary tissue was capable of tonic as well as GRH-stimulated GH release. These results demonstrate that despite similar basal GH levels, animals bearing pituitary grafts release significantly greater amounts of GH in response to GRH. The evidence for GH secretion by individual somatotropes from transplanted pituitary tissue directly shows the grafted tissue to be a source of GRH-stimulated GH. The lack of beta-adrenergic inhibition of GRH-induced GH release in pituitary-grafted animals is consistent with the hypothesis that beta-adrenergic inhibition of GRH-induced GH secretion is mediated by an effect on the hypothalamus.

Hypogonadism does not mediate urinary calcium loss in pituitary-grafted rats

Rats rendered chronically hyperprolactinemic by implantation of extra anterior pituitary glands (AP) under the kidney capsule have excess urinary calcium excretion. Although serum testosterone levels are normal in male AP-grafted rats, more subtle androgen deficiency might contribute to the increased calcium loss. Female AP-grafted rats lose the normal estrous cycle, which might also alter calcium homeostasis. The urinary calcium and calcium/sodium excretion ratio in gonadectomized AP-grafted rats of both sexes were compared with that of otherwise intact AP-grafted rats and muscle-grafted control rats. AP-grafted rats had increased urinary calcium excretion and calcium/sodium excretion ratio, regardless of gonadal status. Treatment of castrated male AP-grafted animals with testosterone or dihydrotestosterone did not have a significant effect on urinary calcium loss, nor did estrogen replacement of ovariectomized female AP-grafted rats. These studies indicate that the hypercalciuria of the AP-grafted rat is not mediated via an anti-gonadal effect of the prolactin-secreting pituitary graft.

Insulin pump treatment of type I diabetes mellitus in a patient with C6 quadriplegia

A 40-year-old patient with insulin-dependent (Type I) diabetes mellitus since childhood suffered a C6 spinal transection. Recurrent episodes of hypoglycemia resolved after the patient was placed on an insulin pump. The patient is able to set the insulin delivery rate and maintain the pump without assistance. Spinal cord injured patients may lack both the clinical symptoms of, and the ability to respond to, hypoglycemia. The mixing of NPH insulin and regular insulin requires fine motor skills; even with prefilled syringes, the quadriplegic person may have difficulty with subcutaneous injection. The use of an "open loop" insulin pump averts these problems and may provide better glucose control for selected spinal cord injury patients with Type I diabetes.

Examination of hypercalciuria in anterior pituitary-implanted rats

The anterior pituitary (AP) grafted, adrenalectomized, steroid hormone-replaced male rat is characterized by hyperprolactinemia and hypercalciuria. To determine the origin of the hypercalciuria, clearance experiments were performed under Inactin anesthesia in adrenalectomized Fischer rats 8-10 wk after implantation of extra AP glands under the kidney capsule. Glomerular filtration rate, ultrafilterable calcium, and fractional sodium excretion were comparable in the AP and control groups. However, fractional calcium excretion was significantly higher in the AP-implanted rats, P less than 0.05, resulting in a marked dissociation of the calcium/sodium clearance ratio. Because filtered calcium load did not change, these results clearly demonstrate that AP-implanted animals have a defect in tubular calcium reabsorption. The dissociation of calcium transport from sodium transport suggests the distal tubule as a likely site of action. Parathyroidectomy did not alter the calciuric response to AP implantation. To test whether hyperprolactinemia was responsible for decreased calcium reabsorption in AP-implanted rats, purified rat prolactin was infused into normal rats to achieve high blood prolactin levels, or was injected into normal rats daily for 8 days. Changes in fractional calcium excretion and the ratio of calcium to sodium clearance were identical in animals receiving prolactin or control infusions. Thus, hypercalciuria in the AP-implanted rat may be attributed to an unidentified factor, perhaps secreted from the implanted anterior pituitaries, rather than to prolactin excess.