People: Staff Scientists

Biostatistician 2, Med/Quantitative Sciences Unit

Publications

  • Effect of Medicare's Nonpayment Policy on Surgical Site Infections Following Orthopedic Procedures. Infection control and hospital epidemiology Kwong, J. Z., Weng, Y., Finnegan, M., Schaffer, R., Remington, A., Curtin, C., McDonald, K. M., Bhattacharya, J., Hernandez-Boussard, T. 2017: 1-6

    Abstract

    OBJECTIVE Orthopedic procedures are an important focus in efforts to reduce surgical site infections (SSIs). In 2008, the Centers for Medicare and Medicaid (CMS) stopped reimbursements for additional charges associated with serious hospital-acquired conditions, including SSI following certain orthopedic procedures. We aimed to evaluate the CMS policy's effect on rates of targeted orthopedic SSIs among the Medicare population. DESIGN We examined SSI rates following orthopedic procedures among the Medicare population before and after policy implementation compared to a similarly aged control group. Using the Nationwide Inpatient Sample database for 2000-2013, we estimated rate ratios (RRs) of orthopedic SSIs among Medicare and non-Medicare patients using a difference-in-differences approach. RESULTS Following policy implementation, SSIs significantly decreased among both the Medicare and non-Medicare populations (RR, 0.7; 95% confidence interval [CI], 0.6-0.8) and RR, 0.8l; 95% CI, 0.7-0.9), respectively. However, the estimated decrease among the Medicare population was not significantly greater than the decrease among the control population (RR, 0.9; 95% CI, 0.8-1.1). CONCLUSIONS While SSI rates decreased significantly following the implementation of the CMS nonpayment policy, this trend was not associated with policy intervention but rather larger secular trends that likely contributed to decreasing SSI rates over time. Infect Control Hosp Epidemiol 2017;1-6.

    View details for DOI 10.1017/ice.2017.86

    View details for PubMedID 28487001

Data Engineer Lead, SoM - IRT Research Technology

Publications

  • Higher Absolute Lymphocyte Counts Predict Lower Mortality from Early-Stage Triple-Negative Breast Cancer. Clinical cancer research : an official journal of the American Association for Cancer Research Afghahi, A., Purington, N., Han, S. S., Desai, M., Pierson, E., Mathur, M. B., Seto, T., Thompson, C. A., Rigdon, J., Telli, M. L., Badve, S. S., Curtis, C., West, R. B., Horst, K., Gomez, S. L., Ford, J. M., Sledge, G. W., Kurian, A. W. 2018

    Abstract

    Tumor-infiltrating lymphocytes (TILs) in pre-treatment biopsies are associated with improved survival in triple-negative breast cancer (TNBC). We investigated whether higher peripheral lymphocyte counts are associated with lower breast cancer-specific mortality (BCM) and overall mortality (OM) in TNBC.Data on treatments and diagnostic tests from electronic medical records of two healthcare systems were linked with demographic, clinical, pathologic, and mortality data from the California Cancer Registry. Multivariable regression models adjusted for age, race/ethnicity, socioeconomic status, cancer stage, grade, neoadjuvant/adjuvant chemotherapy use, radiotherapy use, and germline BRCA1/2 mutations were used to evaluate associations between absolute lymphocyte count (ALC), BCM and OM. For a subgroup with TILs data available, we explored the relationship between TILs and peripheral lymphocyte counts.1,463 Stage I-III TNBC patients were diagnosed from 2000-2014; 1113 (76%) received neoadjuvant/adjuvant chemotherapy within one year of diagnosis. Of 759 patients with available ALC data, 481 (63.4%) were ever lymphopenic (minimum ALC <1.0 K/μL). On multivariable analysis, higher minimum ALC, but not absolute neutrophil count, predicted lower OM (hazard ratio [HR]: 0.23, 95% confidence interval [CI]: 0.16-0.35) and BCM (HR: 0.19, CI: 0.11-0.34). Five-year probability of BCM was 15% for patients who were ever lymphopenic versus 4% for those who were not. An exploratory analysis (N=70) showed a significant association between TILs and higher peripheral lymphocyte counts during neoadjuvant chemotherapy.Higher peripheral lymphocyte counts predicted lower mortality from early-stage, potentially curable TNBC, suggesting that immune function may enhance the effectiveness of early TNBC treatment.

    View details for DOI 10.1158/1078-0432.CCR-17-1323

    View details for PubMedID 29581131