Developing vitamin D dietary guidelines and the lack of 25-hydroxyvitamin D assay standardization: The ever-present past

Unstandardized laboratory measurement of 25-hydroxyvitamin D (25(OH)D) confounds efforts to develop clinical and public health vitamin D guidelines. The Vitamin D Standardization Program (VDSP), an international collaborative effort, was founded in 2010 to correct this problem. Nearly all published vitamin D research is based on unstandardized laboratory 25(OH)D measurements. While it is impossible to standardize all old data, it may be possible to identify a small subset of prior studies critical to guidelines development. Once identified it may be possible to calibrate their 25(OH)D values to the NIST and Ghent University reference measurement procedures using VDSP methods thereby permitting future guidelines to be based on standardized results. We simulated the calibration of a small set of ten clinical trials of vitamin D supplementation on achieved 25(OH)D under minimal sun exposure. These studies were selected because they played a prominent role in setting the 2010 vitamin D dietary reference intakes (DRI). Using random-effects meta-regression analysis, Vitamin D External Quality Assessment (DEQAS) data on assay bias was used to simulate the potential bias due to the lack of assay standardization by calibrating the achieved 25(OH)D levels from those 10 studies to: (1) the largest negative, and (2) the largest positive bias from the DEQAS all laboratory trimmed mean (ALTM) for the appropriate assay and year of analysis. For a usual vitamin D intake of 600IU/day the difference in mean achieved 25(OH)D values for those two options was 20nmol/L. However, without re-calibration of 25(OH)D values it is impossible to know the degree to which any of the current guidelines may have been biased. This approach may help stimulate the search for and standardization of that small subset of key studies and, in the cases where standardization is impossible, to identify areas of urgently needed vitamin D research.

Accuracy and cost-effectiveness of dynamic contrast-enhanced CT in the characterisation of solitary pulmonary nodules-the SPUtNIk study

INTRODUCTION

Solitary pulmonary nodules (SPNs) are common on CT. The most cost-effective investigation algorithm is still to be determined. Dynamic contrast-enhanced CT (DCE-CT) is an established diagnostic test not widely available in the UK currently.

METHODS AND ANALYSIS

The SPUtNIk study will assess the diagnostic accuracy, clinical utility and cost-effectiveness of DCE-CT, alongside the current CT and 18-flurodeoxyglucose-positron emission tomography) (18FDG-PET)-CT nodule characterisation strategies in the National Health Service (NHS). Image acquisition and data analysis for 18FDG-PET-CT and DCE-CT will follow a standardised protocol with central review of 10% to ensure quality assurance. Decision analytic modelling will assess the likely costs and health outcomes resulting from incorporation of DCE-CT into management strategies for patients with SPNs.

ETHICS AND DISSEMINATION

Approval has been granted by the South West Research Ethics Committee. Ethics reference number 12/SW/0206. The results of the trial will be presented at national and international meetings and published in an Health Technology Assessment (HTA) Monograph and in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

ISRCTN30784948; Pre-results.

Use of tissue plasminogen activator in the treatment of shunt blockage secondary to intraventricular haemorrhage

A 51-year-old woman with a history of idiopathic aqueduct stenosis, treated initially with insertion of a ventriculo peritoneal shunt, presented to our institution with shunt dysfunction. She had previously undergone multiple shunt revisions for shunt infection, shunt blockage and low-pressure symptoms, most recently with conversion to a ventriculo atrial (VA) shunt. Her VA shunt was again revised, with replacement of the ventricular catheter, however surgery was complicated by a large intraventricular haemorrhage (IVH) requiring placement of an external ventricular drain (EVD). Prior to eventual removal of her EVD it was determined that the VA shunt had blocked as a result of the IVH. Subsequently alteplase, a recombinant tissue plasminogen activator (tPA), was administered into the shunt reservoir, resulting in successful return of shunt function, therefore avoiding the need for further shunt revision. This is the first description of the use of tPA to unblock a shunt obstructed by blood.

The prevalence and nature of supportive care needs in lung cancer patients

PURPOSE

In the present work, we set out to comprehensively describe the unmet supportive care and information needs of lung cancer patients.

METHODS

This cross-sectional study used the Supportive Care Needs Survey Short Form 34 (34 items) and an informational needs survey (8 items). Patients with primary lung cancer in any phase of survivorship were included. Demographic data and treatment details were collected from the medical charts of participants. The unmet needs were determined overall and by domain. Univariable and multivariable regression analyses were performed to determine factors associated with greater unmet needs.

RESULTS

From August 2013 to February 2014, 89 patients [44 (49%) men; median age: 71 years (range: 44-89 years)] were recruited. The mean number of unmet needs was 8 (range: 0-34), and 69 patients (78%) reported at least 1 unmet need. The need proportions by domain were 52% health system and information, 66% psychological, 58% physical, 24% patient care, and 20% sexuality. The top 2 unmet needs were "fears of the cancer spreading" [n = 44 of 84 (52%)] and "lack of energy/tiredness" [n = 42 of 88 (48%)]. On multivariable analysis, more advanced disease and higher MD Anderson Symptom Inventory scores were associated with increased unmet needs. Patients reported that the most desired information needs were those for information on managing symptoms such as fatigue (78%), shortness of breath (77%), and cough (63%).

CONCLUSIONS

Unmet supportive care needs are common in lung cancer patients, with some patients experiencing a very high number of unmet needs. Further work is needed to develop resources to address those needs.

A national follow-up survey of UK graduates opinion of undergraduate oral surgery teaching

INTRODUCTION

A national follow-up survey was undertaken to determine whether dental graduates from 2009 perceived that their undergraduate oral surgery education had equipped them for general dental practice 4 years after graduating.

MATERIALS AND METHODS

Graduates from the same 13 United Kingdom dental schools who had taken part in the original survey were invited to take part in this follow-up online survey. Their contact details were identified via the general dental council register, social media and alumni groups.

RESULTS

In total, 161 responded (2009b) which represents 16% of the graduates of the original survey in 2009a. A similar percentage of these respondents perceived that the teaching in oral surgery had given them sufficient knowledge to undertake independent practice (83% and 79% in 2009a and 2009b, respectively). Most respondents (99% in both years) reported confidence in undertaking simple forceps exodontia. Confidence in surgical exodontia was poor in both surveys, but one area that appeared improved in the follow-up related to the sectioning of teeth (84% in 2009b compared with 49% in 2009a). Areas of weakness identified in 2009 were reported to be improved in the follow-up.

CONCLUSION

This follow-up survey supports the findings of the original survey. Future longitudinal studies would allow institutions to identify possible weaknesses in their curriculum and to track the career development of their graduates and facilitate robust data collection.

Tolerance of weekly metronomic paclitaxel and carboplatin as neoadjuvant chemotherapy in advanced ovarian cancer patients who are unlikely to tolerate 3 weekly paclitaxel and carboplatin

OBJECTIVE

There are little data regarding safety and effectiveness of neoadjuvant chemotherapy (NACT) in patients who are considered unfit for receiving 3 weekly paclitaxel and carboplatin. The aim of this study was to examine the toxicity and response rates of weekly paclitaxel and carboplatin as NACT in such cohort of patients.

METHODS

Study population included advanced ovarian cancer patients who were unlikely to tolerate 3 weekly paclitaxel and carboplatin and hence received weekly paclitaxel (80 mg/m(2)) and carboplatin AUC-2 as NACT. The data regarding the baseline characteristics, chemotherapy tolerance, completion rates, toxicity (Common Terminology Criteria for Adverse Events version 4.02), and radiological response rates are presented. SPSS version 16 was used for analysis. Descriptive statistics is presented.

RESULTS

Eleven patients received this schedule. Nine patients completed nine cycles of NACT. Except one, all patients completed NACT with an average relative dose intensity of >0.8. There was no chemotherapy-related mortality. Grade 3-4 life-threatening complications were seen in two patients. The post NACT response rate was 100%.

CONCLUSIONS

Weekly paclitaxel and carboplatin chemotherapy is safe and efficacious in patients who are unsuitable for 3 weekly paclitaxel and carboplatin chemotherapy schedules.

The use of qualitative methods to inform Delphi surveys in core outcome set development

Background

Core outcome sets (COS) help to minimise bias in trials and facilitate evidence synthesis. Delphi surveys are increasingly being used as part of a wider process to reach consensus about what outcomes should be included in a COS. Qualitative research can be used to inform the development of Delphi surveys. This is an advance in the field of COS development and one which is potentially valuable; however, little guidance exists for COS developers on how best to use qualitative methods and what the challenges are. This paper aims to provide early guidance on the potential role and contribution of qualitative research in this area. We hope the ideas we present will be challenged, critiqued and built upon by others exploring the role of qualitative research in COS development.

This paper draws upon the experiences of using qualitative methods in the pre-Delphi stage of the development of three different COS. Using these studies as examples, we identify some of the ways that qualitative research might contribute to COS development, the challenges in using such methods and areas where future research is required.

Results

Qualitative research can help to identify what outcomes are important to stakeholders; facilitate understanding of why some outcomes may be more important than others, determine the scope of outcomes; identify appropriate language for use in the Delphi survey and inform comparisons between stakeholder data and other sources, such as systematic reviews. Developers need to consider a number of methodological points when using qualitative research: specifically, which stakeholders to involve, how to sample participants, which data collection methods are most appropriate, how to consider outcomes with stakeholders and how to analyse these data. A number of areas for future research are identified.

Conclusions

Qualitative research has the potential to increase the research community’s confidence in COS, although this will be dependent upon using rigorous and appropriate methodology. We have begun to identify some issues for COS developers to consider in using qualitative methods to inform the development of Delphi surveys in this article.

Effectiveness of centre-based childcare interventions in increasing child physical activity: a systematic review and meta-analysis for policymakers and practitioners

CONTEXT

The review describes the effectiveness of physical activity interventions implemented in centre-based childcare services and (i) examines characteristics of interventions that may influence intervention effects; (ii) describes the effects of pragmatic interventions and non-pragmatic interventions; (iii) assesses adverse effects; and (iv) describes cost-effectiveness of interventions

METHODS

Data sources were Cochrane Central Register of Controlled trials, MEDLINE, EMBASE, PsycINFO, ERIC, CINAHL, SCOPUS and SPORTDISCUS. Studies selected included randomized controlled trials conducted in centre-based childcare including an intervention to increase objectively measured physical activity in children aged less than 6 years. Data were converted into standardized mean difference (SMD) and analysed using a random effects model.

RESULTS

Overall interventions significantly improved child physical activity (SMD 0.44; 95% confidence interval [CI]: 0.12-0.76). Significant effects were found for interventions that included structured activity (SMD 0.53; 95% CI: 0.12-0.94), delivery by experts (SMD 1.26; 95% CI: 0.20-2.32) and used theory (SMD 0.76; 95% CI: 0.08-1.44). Non-pragmatic (SMD 0.80; 95% CI: 0.12-1.48) but not pragmatic interventions (SMD 0.10; 95% CI:-0.13-0.33) improved child physical activity. One trial reported adverse events, and no trials reported cost data.

CONCLUSIONS

Intervention effectiveness varied according to intervention and trial design characteristics. Pragmatic trials were not effective, and information on cost and adverse effects was lacking. Evidence gaps remain for policymakers and practitioners regarding the effectiveness and feasibility of childcare-based physical activity interventions.

Implementation and evaluation of a transit dosimetry system for treatment verification

PURPOSE

To evaluate a formalism for transit dosimetry using a phantom study and prospectively evaluate the protocol on a patient population undergoing 3D conformal radiotherapy.

METHODS

Amorphous silicon EPIDs were calibrated for dose and used to acquire images of delivered fields. The measured EPID dose map was back-projected using the planning CT images to calculate dose at pre-specified points within the patient using commercially available software, EPIgray (DOSIsoft, France). This software compared computed back-projected dose with treatment planning system dose. A series of tests were performed on solid water phantoms (linearity, field size effects, off-axis effects). 37 patients were enrolled in the prospective study.

RESULTS

The EPID dose response was stable and linear with dose. For all tested field sizes the agreement was good between EPID-derived and treatment planning system dose in the central axis, with performance stability up to a measured depth of 18cm (agreement within -0.5% at 10cm depth on the central axis and within -1.4% at 2cm off-axis). 126 transit images were analysed of 37 3D-conformal patients. Patient results demonstrated the potential of EPIgray with 91% of all delivered fields achieved the initial set tolerance level of ΔD of 0±5-cGy or %ΔD of 0±5%.

CONCLUSIONS

The in vivo dose verification method was simple to implement, with very few commissioning measurements needed. The system required no extra dose to the patient, and importantly was able to detect patient position errors that impacted on dose delivery in two of cases.

Does the use of induction chemotherapy in oral cavity cancer compromise subsequent loco-regional treatment delivery: Results from a matched pair analysis

BACKGROUND

Neoadjuvant chemotherapy is being increasingly used in patients with unresectable oral cavity cancers to make them resectable. However, its impact on locoregional treatment delivery in such setting remains poorly studied.

AIMS

To evaluate the impact of neoadjuvant chemotherapy on delivery of further locoregional treatment.

SETTINGS AND DESIGN

Mono institutional retrospective audit of patients with oral cavity squamous cell cancers treated with neoadjuvant triplet chemotherapy in India.

MATERIALS AND METHODS

Patients receiving neoadjuvant chemotherapy (n = 14) from May 2012 to April 2014 were matched 1:2 to patients undergoing upfront surgery (n = 28) based on age (>60 or 60 and less), gender (male or female) and subsite site (tongue and floor of mouth or buccoalveolar complex). Data regarding factors related to the delivery of locoregional treatment and toxicities were compiled.

STATISTICAL ANALYSIS

Descriptive analysis in the form of median (range) for continuous variables and frequencies for categorical variables.

RESULTS

Patients undergoing neoadjuvant chemotherapy required more extensive resections and had greater operative time (460 vs. 415 min, P < 0.001). A greater incidence of locoregional wound complications was seen as a consequence (57.1% vs. 14.3%, P, 0.01). However, toxicities during radiotherapy were not substantially different between the two groups and compliance to radiation was also similar. Total package time of 100 days or less, was maintained in 90% of patients in both groups.

CONCLUSIONS

Delivery of neoadjuvant chemotherapy does not impair the ability to deliver locoregional treatment.

Direct and Indirect Costs Following Living Kidney Donation: Findings From the KDOC Study

Some living kidney donors (LKDs) incur costs associated with donation, although these costs are not well characterized in the United States. We collected cost data in the 12 mo following donation from 182 LKDs participating in the multicenter prospective Kidney Donor Outcomes Cohort (KDOC) Study. Most LKDs (n = 167, 92%) had one direct cost or more following donation, including ground transportation (86%), health care (41%), meals (53%), medications (36%), lodging (23%), and air transportation (12%). LKDs missed 33 072 total work hours, 40% of which were unpaid and led to $302 175 in lost wages (mean $1660). Caregivers lost $68 655 in wages (mean $377). Although some donors received financial assistance, 89% had a net financial loss in the 12-mo period, with one-third (33%) reporting a loss exceeding $2500. Financial burden was higher for those with greater travel distance to the transplant center (Spearman's ρ = 0.26, p < 0.001), lower household income (Spearman's ρ = -0.25, p < 0.001), and more unpaid work hours missed (Spearman's ρ = 0.52, p < 0.001). Achieving financial neutrality for LKDs must be an immediate priority for the transplant community, governmental agencies, insurance companies, nonprofit organizations, and society at large.

Abstract P3-07-29: Role of germline BRCA status and tumor homologous recombination (HR) deficiency in response to neoadjuvant weekly paclitaxel followed by anthracycline-based chemotherapy

Background: Both HR deficiency and BRCA mutation status predict response to platinum-based therapy and BRCA mutation status predicts docetaxel resistance. However, the association of either biomarker with response to the individual elements of either AC or taxanes (T) is unknown since T is commonly given concomitantly with or after anthracyclines (A). We evaluated the association of HRD and BRCA mutation status with response to neoadjuvant weekly T followed by AC or (F)EC in high-risk breast cancer.

Methods: We studied 140 high risk Stage I-III breast cancer patients (pts), enrolled in the breast cancer genome guided therapy study (BEAUTY), obtaining biopsies for DNA/RNA sequencing and MRI imaging to assess response to neoadjuvant weekly T (+trastuzumab+/-pertuzumab for HER2+ disease) followed by AC or (F)EC. Germline BRCA status and HR status of tumor samples (Myriad laboratories) were obtained. HR deficient tumor was defined as HRD score ≥42 or BRCA mutation. MRI response by changes in tumor size after 12 weeks of T was classified by WHO criteria. pCR was defined as ypT0/Tis ypN0. Both MRI response after T and pCR (after T and AC) were examined in terms of germline BRCA mutation (gBRCAmut vs. gBRCAwt) and tumor HR deficiency.

Results: Of 140 pts enrolled, 8 withdrew consent and 2 carboplatin treated pts were excluded. Germline data were available for 124/130 pts. 12 patients had BRCA deleterious germline mutations (4 BRCA1, 8 BRCA2). MRI partial (PR)/complete response (CR) rate to T was 47.3% (95% CI: 37.8-57.0%) in the BRCAwt group and 66.7% (95% CI: 34.9-90.1%) in the BRCAmut group. No MRI CR's were observed in BRCA1 mut pts. In contrast, pCR rate was 50% in the 12 gBRCAmut pts (95% CI: 21.1-78.9%) and 31.3% in the 112 gBRCAwt pts (95% CI: 22.8-40.7%). HR deficiency status has thus far been determined for 74 pts: 26 pts have HD deficient tumors: 18 TNBC, 5 Luminal B, 2 ER-/HER2+; and 1 ER+/HER2+. Determination of HR deficiency is ongoing and will be reported for the full cohort in terms of 12 week MRI response to T and pCR to T+AC.

 HR deficientMolecular Subtypeyes (%)no (%)TBD (%)Luminal A0/112/11 (18.2)9/11 (81.8)Luminal B5/37 (13.5)13/37 (35.1)19/37 (51.3)Luminal NOS0/21/2 (50)1/2 (50)ER+/Her2+1/17 (5.8)14/17 (82.4)2/17 (11.8)ER-/Her2+2/20 (10)11/20 (55)7/20 (35)Triple Negative18/43 (41.9)6/43 (18.6)17/43 (39.5)germline BRCA statusMRI partial response after T (%)MRI complete response after T (%)pCR after T&AC (%)BRCA11/4 (25)0/42/4 (50)BRCA25/8 (62.5)2/8 (25)4/8 (50)BRCAwt35/112 (31.3)18/112 (16.1)35/112 (31.3)

Conclusion: In the setting of neoadjuvant weekly T followed by AC, pCR rates were non-significantly higher in pts with BRCA1 mutations. While we observed no overall association between BRCA mutation status and response rates to taxanes; nearly all MRI responses to taxanes (partial and complete) were observed in the BRCA2 group. Prospective studies are needed to validate these findings and to determine whether BRCA status can be used to select therapy. HR deficiency is uncommon in luminal A and HER2+, frequent in TNBC, and the association of HRD with both MRI response to taxanes and pCR will be reported at the meeting.

Citation Format: Boughey JC, Kalari KR, Suman VJ, McLaughlin SA, Moreno Aspitia A, Moyer AM, Northfelt DW, Gray RJ, Vedell PT, Tang X, Dockter TJ, Jones KN, Felten SJ, Conners AL, Hart SN, Visscher DW, Wieben ED, Ingle JN, Hartman A-R, Timms K, Elkin E, Jones J, Wang L, Weinshilboum RW, Goetz MP. Role of germline BRCA status and tumor homologous recombination (HR) deficiency in response to neoadjuvant weekly paclitaxel followed by anthracycline-based chemotherapy. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P3-07-29.

Promoting early presentation of breast cancer in women over 70 years old in general practice

BACKGROUND

Delay in presentation contributes to poorer survival of older women with breast cancer. Research has shown the effectiveness of the promoting early presentation (PEP) intervention when delivered by radiographers in the NHS Breast Screening Programme. This paper investigates the effectiveness of the intervention when delivered by practice nurses in general practice.

METHODS

The Breast Cancer Awareness Measure was used to compare participants' awareness of breast cancer before, 1 month after and 12 months after the delivery of the PEP intervention. Five hundred and fifty-six women aged over 70 years took part, 308 of whom returned all three surveys.

RESULTS

The intervention was associated with increased awareness of non-lump breast symptoms and reported breast check frequency. There was a marked increase in breast cancer awareness which persisted for 12 months. Less than 5% of women were classified as 'breast cancer aware' before the intervention, rising to over 25% 1 month afterwards. This percentage dropped slightly after 1 year to just below 20%.

CONCLUSION

Delivery of the PEP intervention in general practice was very effective at raising the awareness of breast cancer among older women. Primary care settings are well placed to enhance the reach of this kind of intervention to at-risk women.

Predonation Direct and Indirect Costs Incurred by Adults Who Donated a Kidney: Findings From the KDOC Study

Limited information exists on the predonation costs incurred by eventual living kidney donors (LKDs). Expenses related to completion of the donation evaluation were collected from 194 LKDs participating in the multi-center, prospective Kidney Donor Outcomes Cohort (KDOC) Study. Most LKDs (n = 187, 96%) reported one or more direct costs, including ground transportation (80%), healthcare (24%), lodging (17%) and air transportation (14%), totaling $101 484 (USD; mean = $523 ± 942). Excluding paid vacation or sick leave, donor and companion lost wages totaled $35 918 (mean = $187 ± 556) and $14 378 (mean = $76 ± 311), respectively. One-third of LKDs used paid vacation or sick leave to avoid incurring lost wages. Few LKDs reported receiving financial support from the transplant candidate (6%), transplant candidate's family (3%), a nonprofit organization (3%), the National Living Donor Assistance Center (7%), or transplant center (3%). Higher total costs were significantly associated with longer distance traveled to the transplant center (p < 0.001); however, total costs were not associated with age, sex, race/ethnicity, household income, marital status, insurance status, or transplant center. Moderate predonation direct and indirect costs are common for adults who complete the donation evaluation. Potential LKDs should be advised of these possible costs, and the transplant community should examine additional strategies to reimburse donors for them.

Reasons for nonadherence to tamoxifen and aromatase inhibitors for the treatment of breast cancer: a literature review

Despite improved breast cancer survival rates with the use of tamoxifen and aromatase inhibitors, patients remain at risk for cancer recurrence and mortality because of nonadherence to medication. The objective of this review was to identify factors associated with nonadherence among patients with breast cancer. Electronic databases were searched for studies, and potentially relevant studies were retrieved and assessed for eligibility. Potential factors associated with nonadherence were identified, and they included patient-related factors (e.g., patient beliefs and knowledge, fear of adverse effects, forgetfulness, smoking, age, race), therapy-related factors (e.g., duration, side effects, additional prescribed medications, treatment interfering with lifestyle), healthcare system factors (e.g., patient/provider relationships), socioeconomic factors (e.g., medication costs, burden, scheduling problems, religion, marital status), and disease-related factors (e.g., comorbidities, stage of breast cancer). Those findings highlight the need for development of interventions to promote long-term adherence in patients with breast cancer.

High rates of fatigue and sleep disturbances in dystonia

BACKGROUND

Nonmotor symptoms in dystonia are increasingly recognized to impair the quality of life. The primary objective of this study was to determine the prevalence of fatigue and sleep disturbances in dystonia and to ascertain their impact on quality of life using standardized questionnaires.

METHODS

Dystonia patients presenting to a Botulinum toxin clinic were prospectively administered Fatigue Severity Scale (FSS), Multidimensional Fatigue Inventory (MFI), Epworth Sleepiness Scale (ESS) and Parkinson's Disease Sleep Scale (PDSS) for assessment of fatigue and sleep disturbances. Health-related Quality of life (HRQOL) was determined using MOS SF-36 scale and depressive symptoms were assessed using the Beck Depression Inventory II.

RESULTS

Ninety-one patients with dystonia participated (66 women, 25 men, mean age 60 ± 17 years). Nine subjects had generalized dystonia, 18 segmental dystonia and 64 had focal dystonia. Moderate to severe fatigue was present in 43% of the cohort (FSS), excessive daytime somnolence in 27% (ESS) and other sleep disturbances in 26% (PDSS). FSS and MFI scores correlated significantly with HRQOL even when controlled for depression and sleep disturbances. Excessive daytime somnolence and nocturnal sleep disturbances correlated significantly with the HRQOL; however, these effects were not seen for daytime somnolence when controlled for depression. Psychometric testing found adequate reliabilities and convergent validities for both fatigue and sleep scales.

CONCLUSION

Fatigue and sleep disturbances revealed high prevalence rates in this large, first of its dystonia study. They negatively impacted the quality of life even when controlled for comorbid depression.

Hypothesis generation using network structures on community health center cancer-screening performance

RESEARCH OBJECTIVES

Nationally sponsored cancer-care quality-improvement efforts have been deployed in community health centers to increase breast, cervical, and colorectal cancer-screening rates among vulnerable populations. Despite several immediate and short-term gains, screening rates remain below national benchmark objectives. Overall improvement has been both difficult to sustain over time in some organizational settings and/or challenging to diffuse to other settings as repeatable best practices. Reasons for this include facility-level changes, which typically occur in dynamic organizational environments that are complex, adaptive, and unpredictable. This study seeks to understand the factors that shape community health center facility-level cancer-screening performance over time. This study applies a computational-modeling approach, combining principles of health-services research, health informatics, network theory, and systems science.

METHODS

To investigate the roles of knowledge acquisition, retention, and sharing within the setting of the community health center and to examine their effects on the relationship between clinical decision support capabilities and improvement in cancer-screening rate improvement, we employed Construct-TM to create simulated community health centers using previously collected point-in-time survey data. Construct-TM is a multi-agent model of network evolution. Because social, knowledge, and belief networks co-evolve, groups and organizations are treated as complex systems to capture the variability of human and organizational factors. In Construct-TM, individuals and groups interact by communicating, learning, and making decisions in a continuous cycle. Data from the survey was used to differentiate high-performing simulated community health centers from low-performing ones based on computer-based decision support usage and self-reported cancer-screening improvement.

RESULTS

This virtual experiment revealed that patterns of overall network symmetry, agent cohesion, and connectedness varied by community health center performance level. Visual assessment of both the agent-to-agent knowledge sharing network and agent-to-resource knowledge use network diagrams demonstrated that community health centers labeled as high performers typically showed higher levels of collaboration and cohesiveness among agent classes, faster knowledge-absorption rates, and fewer agents that were unconnected to key knowledge resources. Conclusions and research implications: Using the point-in-time survey data outlining community health center cancer-screening practices, our computational model successfully distinguished between high and low performers. Results indicated that high-performance environments displayed distinctive network characteristics in patterns of interaction among agents, as well as in the access and utilization of key knowledge resources. Our study demonstrated how non-network-specific data obtained from a point-in-time survey can be employed to forecast community health center performance over time, thereby enhancing the sustainability of long-term strategic-improvement efforts. Our results revealed a strategic profile for community health center cancer-screening improvement via simulation over a projected 10-year period. The use of computational modeling allows additional inferential knowledge to be drawn from existing data when examining organizational performance in increasingly complex environments.

Metabolically healthy and unhealthy obesity: differential effects on myocardial function according to metabolic syndrome, rather than obesity

BACKGROUND

The term 'metabolically healthy obese (MHO)' is distinguished using body mass index (BMI), yet BMI is a poor index of adiposity. Some epidemiological data suggest that MHO carries a lower risk of cardiovascular disease (CVD) or mortality than being normal weight yet metabolically unhealthy.

OBJECTIVES

We aimed to undertake a detailed phenotyping of individuals with MHO by using imaging techniques to examine ectopic fat (visceral and liver fat deposition) and myocardial function. We hypothesised that metabolically unhealthy individuals (irrespective of BMI) would have adverse levels of ectopic fat and myocardial dysfunction compared with MHO individuals.

SUBJECTS

Individuals were categorised as non-obese or obese (BMI ⩾30 kg m(-2)) and as metabolically healthy or unhealthy according to the presence or absence of metabolic syndrome.

METHODS

Sixty-seven individuals (mean±s.d.: age 49±11 years) underwent measurement of (i) visceral, subcutaneous and liver fat using magnetic resonance imaging and proton magnetic resonance spectroscopy, (ii) components of metabolic syndrome, (iii) cardiorespiratory fitness and (iv) indices of systolic and diastolic function using tissue Doppler echocardiography.

RESULTS

Cardiorespiratory fitness was similar between all groups; abdominal and visceral fat was highest in the obese groups. Compared with age- and BMI-matched metabolically healthy counterparts, the unhealthy (lean or obese) individuals had higher liver fat and decreased early diastolic strain rate, early diastolic tissue velocity and systolic strain indicative of subclinical systolic and diastolic dysfunction. The magnitude of dysfunction correlated with the number of components of metabolic syndrome but not with BMI or with the degree of ectopic (visceral or liver) fat deposition.

CONCLUSIONS

Myocardial dysfunction appears to be related to poor metabolic health rather than simply BMI or fat mass. These data may partly explain the epidemiological evidence on CVD risk relating to the different obesity phenotypes.