Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Michaela A. Dinan is active.

Publication


Featured researches published by Michaela A. Dinan.


JAMA | 2010

Changes in the Use and Costs of Diagnostic Imaging Among Medicare Beneficiaries With Cancer, 1999-2006

Michaela A. Dinan; Lesley H. Curtis; Bradley G. Hammill; Edward F. Patz; Amy P. Abernethy; Alisa M. Shea; Kevin A. Schulman

CONTEXT Emerging technologies, changing diagnostic and treatment patterns, and changes in Medicare reimbursement are contributing to increasing use of imaging in cancer. Imaging is the fastest growing expense for Medicare but has not been examined among beneficiaries with cancer. OBJECTIVE To examine changes in the use of imaging and how those changes contribute to the overall cost of cancer care. DESIGN, SETTING, AND PATIENTS Analysis of a nationally representative 5% sample of claims from the US Centers for Medicare & Medicaid Services from 1999 through 2008. Patients were Medicare beneficiaries with incident breast cancer, colorectal cancer, leukemia, lung cancer, non-Hodgkin lymphoma, or prostate cancer. MAIN OUTCOME MEASURES Use and cost of imaging by modality, year, and cancer type. RESULTS There were 100,954 incident cases of breast cancer, colorectal cancer, leukemia, lung cancer, non-Hodgkin lymphoma, and prostate cancer from 1999 through 2006. Significant mean annual increases in imaging use occurred among all cancer types for positron emission tomography (35.9%-53.6%), bone density studies (6.3%-20.0%), echocardiograms (5.0%-7.8%), magnetic resonance imaging (4.4%-11.5%), and ultrasound (0.7%-7.4%). Conventional radiograph rates decreased or stayed the same. As of 2006, beneficiaries with lung cancer and beneficiaries with lymphoma incurred the largest overall imaging costs, exceeding a mean of


Cancer Epidemiology, Biomarkers & Prevention | 2013

Oral Contraceptive Use and Risk of Breast, Cervical, Colorectal, and Endometrial Cancers: A Systematic Review

Jennifer M. Gierisch; Remy R Coeytaux; Rachel Peragallo Urrutia; Laura J. Havrilesky; Patricia G. Moorman; William J. Lowery; Michaela A. Dinan; Amanda J McBroom; Vic Hasselblad; Gillian D Sanders; Evan R. Myers

3000 per beneficiary within 2 years of diagnosis. By 2005, one-third of beneficiaries with breast cancer underwent bone scans and half of beneficiaries with lung cancer or lymphoma underwent positron emission tomography scans. Mean 2-year imaging costs per beneficiary increased at a rate greater than the increase in mean total costs per beneficiary for all cancer types. CONCLUSION Imaging costs among Medicare beneficiaries with cancer increased from 1999 through 2006, outpacing the rate of increase in total costs among Medicare beneficiaries with cancer.


Annals of Surgery | 2014

Extent of Surgery for Papillary Thyroid Cancer Is Not Associated with Survival: An Analysis of 61,775 Patients

Mohamed A. Adam; John Pura; Lin Gu; Michaela A. Dinan; Douglas S. Tyler; Shelby D. Reed; Randall P. Scheri; Sanziana A. Roman; Julie Ann Sosa

Oral contraceptives may influence the risk of certain cancers. As part of the AHRQ Evidence Report, Oral Contraceptive Use for the Primary Prevention of Ovarian Cancer, we conducted a systematic review to estimate associations between oral contraceptive use and breast, cervical, colorectal, and endometrial cancer incidence. We searched PubMed, Embase, and Cochrane Database of Systematic Reviews. Study inclusion criteria were women taking oral contraceptives for contraception or ovarian cancer prevention; includes comparison group with no oral contraceptive use; study reports quantitative associations between oral contraceptive exposure and relevant cancers; controlled study or pooled patient-level meta-analyses; sample size for nonrandomized studies ≥100; peer-reviewed, English-language; published from January 1, 2000 forward. Random-effects meta-analyses were conducted by estimating pooled ORs with 95% confidence intervals (CIs). We included 44 breast, 12 cervical, 11 colorectal, and 9 endometrial cancers studies. Breast cancer incidence was slightly but significantly increased in users (OR, 1.08; CI, 1.00–1.17); results show a higher risk associated with more recent use of oral contraceptives. Risk of cervical cancer was increased with duration of oral contraceptive use in women with human papillomavirus infection; heterogeneity prevented meta-analysis. Colorectal cancer (OR, 0.86; CI, 0.79–0.95) and endometrial cancer incidences (OR, 0.57; CI, 0.43–0.77) were significantly reduced by oral contraceptive use. Compared with never use, ever use of oral contraceptives is significantly associated with decreases in colorectal and endometrial cancers and increases in breast cancers. Although elevated breast cancer risk was small, relatively high incidence of breast cancers means that oral contraceptives may contribute to a substantial number of cases. Cancer Epidemiol Biomarkers Prev; 22(11); 1931–43. ©2013 AACR.


Journal of Clinical Oncology | 2013

Oral Contraceptives and Risk of Ovarian Cancer and Breast Cancer Among High-Risk Women: A Systematic Review and Meta-Analysis

Patricia G. Moorman; Laura J. Havrilesky; Jennifer M. Gierisch; Remy R Coeytaux; William J. Lowery; Rachel Peragallo Urrutia; Michaela A. Dinan; Amanda J McBroom; Vic Hasselblad; Gillian D Sanders; Evan R. Myers

Objective:To examine the association between the extent of surgery and overall survival in a large contemporary cohort of patients with papillary thyroid cancer (PTC). Background:Guidelines recommend total thyroidectomy for PTC tumors >1 cm, based on older data demonstrating an overall survival advantage for total thyroidectomy over lobectomy. Methods:Adult patients with PTC tumors 1.0–4.0 cm undergoing thyroidectomy in the National Cancer Database, 1998–2006, were included. Cox proportional hazards models were applied to measure the association between the extent of surgery and overall survival while adjusting for patient demographic and clinical factors, including comorbidities, extrathyroidal extension, multifocality, nodal and distant metastases, and radioactive iodine treatment. Results:Among 61,775 PTC patients, 54,926 underwent total thyroidectomy and 6849 lobectomy. Compared with lobectomy, patients undergoing total thyroidectomy had more nodal (7% vs 27%), extrathyroidal (5% vs16%), and multifocal disease (29% vs 44%) (all Ps < 0.001). Median follow-up was 82 months (range, 60–179 months). After multivariable adjustment, overall survival was similar in patients undergoing total thyroidectomy versus lobectomy for tumors 1.0–4.0 cm [hazard ratio (HR) = 0.96; 95% confidence interval (CI), 0.84–1.09); P = 0.54] and when stratified by tumor size: 1.0–2.0 cm [HR = 1.05; 95% CI, 0.88–1.26; P = 0.61] and 2.1–4.0 cm [HR = 0.89; 95% CI, 0.73–1.07; P = 0.21]. Older age, male sex, black race, lower income, tumor size, and presence of nodal or distant metastases were independently associated with compromised survival (P < 0.0001). Conclusions:Current guidelines suggest total thyroidectomy for PTC tumors >1 cm. However, we did not observe a survival advantage associated with total thyroidectomy compared with lobectomy. These findings call into question whether tumor size should be an absolute indication for total thyroidectomy.


Obstetrics & Gynecology | 2013

Oral contraceptive pills as primary prevention for ovarian cancer: a systematic review and meta-analysis.

Laura J. Havrilesky; Patricia G. Moorman; Lowery Wj; Jennifer M. Gierisch; Remy R Coeytaux; Rachel Peragallo Urrutia; Michaela A. Dinan; McBroom Aj; Hasselblad; Gillian D Sanders; Evan R. Myers

PURPOSE To estimate the risks of ovarian cancer and breast cancer associated with oral contraceptive (OC) use among women at elevated risk owing to mutations in BRCA1/2 or a strong family history. METHODS We searched PubMed, Embase, the Cochrane Database of Systematic Reviews, and ClinicalTrials.gov for studies published 2000 to 2012 that evaluated associations between OC use and breast or ovarian cancer among women who are carriers of a BRCA1/2 mutation or have a family history of breast or ovarian cancer. RESULTS From 6,476 unique citations, we identified six studies examining ovarian cancer risk in BRCA1/2 mutation carriers and eight studies examining breast cancer risk in BRCA1/2 mutation carriers. For BRCA1/2 mutation carriers combined, meta-analysis showed an inverse association between OC use and ovarian cancer (odds ratio [OR], 0.58; 95% CI, 0.46 to 0.73) and a nonstatistically significant association with breast cancer (OR, 1.21; 95% CI, 0.93 to 1.58). Findings were similar when examining BRCA1 and BRCA2 mutation carriers separately. Data were inadequate to perform meta-analyses examining duration or timing of use. For women with a family history of ovarian or breast cancer, we identified four studies examining risk for ovarian cancer and three for breast cancer, but differences between studies precluded combining the data for meta-analyses, and no overall pattern could be discerned. CONCLUSION Our analyses suggest that associations between ever use of OCs and ovarian and breast cancer among women who are BRCA1 or BRCA2 mutation carriers are similar to those reported for the general population.


Journal of Clinical Oncology | 2015

Presence and Number of Lymph Node Metastases Are Associated With Compromised Survival for Patients Younger Than Age 45 Years With Papillary Thyroid Cancer

Mohamed A. Adam; John Pura; Paolo Goffredo; Michaela A. Dinan; Shelby D. Reed; Randall P. Scheri; Terry Hyslop; Sanziana A. Roman; Julie Ann Sosa

OBJECTIVE: To estimate the overall reduction in ovarian cancer risk associated with the use of oral contraceptive pills (OCPs) and whether reduction in risk is affected by specifics of OCP use, such as formulation or duration of use. DATA SOURCES: We searched PubMed, Embase, the Cochrane Database of Systematic Reviews, and ClinicalTrials.gov for studies published from January 1990 to June 2012, with primary analysis of studies published since January 2000. METHODS OF STUDY SELECTION: We reviewed 6,476 citations. We included English-language controlled studies with human participants reporting a quantitative association between exposure to OCPs (in which the explicit or implicit indication for OCP use was prevention of pregnancy or ovarian cancer) compared with no use of OCPs. Two investigators independently reviewed the title and abstract and full-text of articles for inclusion or exclusion decision; discordant decisions were resolved by team review and consensus. TABULATION, INTEGRATION, AND RESULTS: Fifty-five studies met inclusion criteria. A random-effects meta-analysis of 24 case-control and cohort studies showed significant reduction in ovarian cancer incidence in ever-users compared with never-users (odds ratio 0.73, 95% confidence interval 0.66–0.81). There was a significant duration–response relationship, with reduction in incidence of more than 50% among women using OCPs for 10 or more years. The lifetime reduction in ovarian cancer attributable to the use of OCPs is approximately 0.54% for a number-needed-to-treat of approximately 185 for a use period of 5 years. CONCLUSION: Significant duration-dependent reductions in ovarian cancer incidence in the general population are associated with OCP use.


Obstetrics & Gynecology | 2013

Risk of acute thromboembolic events with oral contraceptive use: a systematic review and meta-analysis.

Peragallo Urrutia R; Remy R Coeytaux; Amanda J McBroom; Jennifer M. Gierisch; Laura J. Havrilesky; Patricia G. Moorman; W.J. Lowery; Michaela A. Dinan; Hasselblad; Gillian D Sanders; Evan R. Myers

PURPOSE Cervical lymph node metastases are recognized as a prognostic indicator only in patients age 45 years or older with papillary thyroid cancer (PTC); patients younger than age 45 years are perceived to have low-risk disease. The current American Joint Committee on Cancer staging for PTC in patients younger than age 45 years does not include cervical lymph node metastases. Our objective was to test the hypothesis that the presence and number of cervical lymph node metastases have an adverse impact on overall survival (OS) in patients younger than age 45 years with PTC. PATIENTS AND METHODS Adult patients younger than age 45 years undergoing surgery for stage I PTC (no distant metastases) were identified from the National Cancer Data Base (NCDB; 1998-2006) and from SEER 1988-2006 data. Multivariable models were used to examine the association of OS with the presence of lymph node metastases and number of metastatic nodes. RESULTS In all, 47,902 patients in NCDB (11,740 with and 36,162 without nodal metastases) and 21,855 in the SEER database (5,188 with and 16,667 without nodal metastases) were included. After adjustment, OS was compromised for patients with nodal metastases compared with patients who did not have them (NCDB: hazard ratio (HR), 1.32; 95% CI, 1.04 to 1.67; P = .021; SEER: HR, 1.29; 95% CI, 1.08 to 1.56; P = .006). After adjustment, increasing number of metastatic lymph nodes was associated with decreasing OS up to six metastatic nodes (HR, 1.12; 95% CI, 1.01 to 1.25; P = .03), after which more positive nodes conferred no additional mortality risk (HR, 0.99; 95% CI, 0.99 to 1.05; P = .75). CONCLUSION Our results suggest that cervical lymph node metastases are associated with compromised survival in young patients, warranting consideration of revised American Joint Committee on Cancer staging. A change point of six or fewer metastatic lymph nodes seems to carry prognostic significance, thus advocating for rigorous preoperative screening for nodal metastases.


Journal of Clinical Oncology | 2012

Stage Migration, Selection Bias, and Survival Associated With the Adoption of Positron Emission Tomography Among Medicare Beneficiaries With Non–Small-Cell Lung Cancer, 1998-2003

Michaela A. Dinan; Lesley H. Curtis; William R. Carpenter; Andrea K. Biddle; Amy P. Abernethy; Edward F. Patz; Kevin A. Schulman; Morris Weinberger

OBJECTIVE: To estimate the risk of venous thromboembolism, stroke, or myocardial infarction (MI) associated with the use of oral contraceptive pills (OCPs) and to describe how these risks vary by dose or formulation. DATA SOURCES: We searched PubMed, Embase, the Cochrane Database of Systematic Reviews, and ClinicalTrials.gov for studies published from January 1995 through June 2012 that evaluated the association between OCP use and risk of venous thromboembolism, stroke, or MI. METHODS OF STUDY SELECTION: We reviewed 6,476 citations. We included English-language, controlled studies with human participants reporting a quantitative association between exposure to OCPs and outcomes of venous thromboembolism, stroke, or MI. Two investigators independently reviewed articles for inclusion or exclusion; discordant decisions were resolved by team review and consensus. Random-effects meta-analysis was used to generate summary odds ratios (ORs). TABULATION, INTEGRATION, AND RESULTS: Fifty studies met inclusion criteria. There were no randomized clinical trials. We found threefold increased odds of venous thromboembolism among current compared with noncurrent OCP users (14 studies; OR 2.97, 95% confidence interval [CI] 2.46–3.59). We found twofold increased odds of ischemic stroke (seven studies; OR 1.90, 95% CI 1.24–2.91). There was no evidence of increased risk of hemorrhagic stroke (four studies; OR 1.03, 95% CI 0.71–1.49) or MI (eight studies; OR 1.34, 95% CI 0.87–2.08). CONCLUSION: Current use of combined OCPs is associated with increased odds of venous thromboembolism and ischemic stroke but not hemorrhagic stroke or MI.


Journal of General Internal Medicine | 2008

Effects of disclosing financial interests on attitudes toward clinical research.

Kevin P. Weinfurt; Mark A. Hall; Michaela A. Dinan; Venita DePuy; Joëlle Y. Friedman; Jennifer S. Allsbrook; Jeremy Sugarman

PURPOSE Previous studies have linked the use of positron emission tomography (PET) with improved outcomes among patients with non-small-cell lung cancer (NSCLC). However, this association may be confounded by PET-induced stage migration and selection bias. We examined the association between PET use and overall survival among Medicare beneficiaries with NSCLC. PATIENTS AND METHODS Retrospective analysis of Surveillance, Epidemiology, and End Results (SEER) -Medicare data was used to characterize changes in overall survival, stage-specific survival, and stage distribution among Medicare beneficiaries with NSCLC between 1998 and 2003. RESULTS A total of 97,007 patients with NSCLC diagnosed between 1998 and 2003 met the study criteria. Two-year and 4-year survival remained unchanged, despite widespread adoption of PET. The proportion of patients staged with advanced disease increased from 44% to 50%. Upstaging of disease was accompanied by stage-specific improved survival, with 2-year survival of stage IV disease increasing from 8% to 11% between 1998 and 2003. PET was more likely to be administered to patients with less advanced disease (stages I through IIIA) and greater overall survival. CONCLUSION Overall survival among Medicare beneficiaries with NSCLC was unchanged between 1998 and 2003, despite widespread adoption of PET. The association between PET use and increased survival likely reflects an artifact of selection bias and consequent stage migration.


The Journal of Clinical Endocrinology and Metabolism | 2015

Impact of extent of surgery on survival for papillary thyroid cancer patients younger than 45 years.

Mohamed A. Adam; John Pura; Paolo Goffredo; Michaela A. Dinan; Terry Hyslop; Shelby D. Reed; Randall P. Scheri; Sanziana A. Roman; Julie Ann Sosa

BackgroundThe effects of disclosing financial interests to potential research participants are not well understood.ObjectiveTo examine the effects of financial interest disclosures on potential research participants’ attitudes toward clinical research.Design and ParticipantsComputerized experiment conducted with 3,623 adults in the United States with either diabetes mellitus or asthma, grouped by lesser and greater severity. Respondents read a description of a hypothetical clinical trial relevant to their diagnosis that included a financial disclosure statement. Respondents received 1 of 5 disclosure statements.MeasurementsWillingness to participate in the hypothetical clinical trial, relative importance of information about the financial interest, change in trust after reading the disclosure statement, surprise regarding the financial interest, and perceived effect of the financial interest on the quality of the clinical trial.ResultsWillingness to participate in the hypothetical clinical trial did not differ substantially among the types of financial disclosures. Respondents viewed the disclosed information as less important than other factors in deciding to participate. Disclosures were associated with some respondents trusting the researchers less, although trust among some respondents increased. Most respondents were not surprised to learn of financial interests. Researchers owning equity were viewed as more troubling than researchers who were compensated for the costs of research through per capita payments.ConclusionsAside from a researcher holding an equity interest, the disclosure to potential research participants of financial interests in research, as recommended in recent policies, is unlikely to affect willingness to participate in research.

Collaboration


Dive into the Michaela A. Dinan's collaboration.

Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Rachel Peragallo Urrutia

University of North Carolina at Chapel Hill

View shared research outputs
Top Co-Authors

Avatar
Researchain Logo
Decentralizing Knowledge