Access to Care in Vermont: Factors Linked With Time to Chemotherapy for Women With Breast Cancer-A Retrospective Cohort Study.

PURPOSE: In the rural United States, there are multiple potential barriers to the timely initiation of chemotherapy. The goal of this study was to identify factors associated with delays in the time from initial diagnosis to first systemic therapy (TTC) among women with breast cancer in Vermont. METHODS: Using data from the Vermont Cancer Registry, we explored TTC for 702 female Vermont residents diagnosed with stage I to III breast cancer between 2006 and 2010 who received adjuvant chemotherapy. Multivariable linear regression was used to evaluate the associations between TTC and patient, tumor, treatment, and geographic variables. RESULTS: Mean TTC was 10.2 weeks. Longer drive time (P < .001), more invasive surgery (P = .01), and breast reconstruction (P < .001) were each associated with longer TTC. Each additional 15 minutes of drive time was associated with a 0.34-week (95% CI, 0.22 to 0.46 weeks) increase in TTC. Participants age younger than 65 years whose primary payer was Medicare (n = 27) had significantly longer average TTC, by 2.37 weeks (P = .001), compared with those with private or military insurance. There was also substantial variation in TTC across hospitals (P < .001). CONCLUSION: Most female patients with stage I to III breast cancer in Vermont are receiving adjuvant chemotherapy within the National Comprehensive Cancer Network-recommended timeframe; however, improvements remain needed for certain subgroups. Novel approaches for women with long drive times need to be developed and evaluated in the community. Variation in TTC by hospital, even after adjusting for patient, tumor, and treatment factors, also suggests opportunities for process improvement.

Historical reconstruction of wastewater and land use impacts to groundwater used for public drinking water: exposure assessment using chemical data and GIS.

Land use in geographic areas that replenish groundwater and surface water resources is increasingly recognized as an important factor affecting drinking water quality. Efforts to understand the implications for health, particularly outcomes with long latency or critical exposure windows, have been hampered by lack of historical exposure data for unregulated pollutants. This limitation has hindered studies of the possible links between breast cancer risk and drinking water impacted by endocrine disrupting compounds and mammary carcinogens, for example. This paper describes a methodology to assess potential historical exposure to a broad range of chemicals associated with wastewater and land use impacts to 132 groundwater wells and one surface water body supplying drinking water to 18 public distribution systems on Cape Cod, MA. We calculated annual measures of impact to each distribution system and used the measures as exposure estimates for the residential addresses of control women in the Cape Cod Breast Cancer and Environment Study (Cape Cod Study). Impact was assessed using (1) historical chemical measurements of nitrate at the water supply sources (performed as required by the Safe Water Drinking Act) and (2) a geographic information system analysis of land use within the zones of contribution (ZOCs) delineated for each well in a state-mandated wellhead protection program. The period for which these impact estimates were developed (1972-1995) was constrained by the availability of chemical measurements and land use data and consideration of time required for groundwater transport of contaminants to the water supply wells. Trends in these estimates for Cape Cod suggest increasing impact to drinking water quality for land use over the study period. Sensitivity analyses were conducted to assess the effect on the distribution of controls' cumulative exposure estimates from (1) reducing the area of the ZOCs to reflect typical well operating conditions rather than extreme pumping conditions used for the regulatory ZOCs, (2) assuming residences received their drinking water entirely from the closest well or cluster of wells rather than a volume-weighted annual district-wide average, and (3) changing the travel time considered for contaminants to reach wells from land use sources. We found that the rank and distribution of controls' cumulative exposure estimates were affected most by the assumption concerning district mixing; in particular, assignment of exposure estimates based on impact values for the closest well(s) consistently produced a larger number of unexposed controls than when a district-wide average impact value was used. As expected, the results suggest that adequate characterization of water quality heterogeneity within water supplies is an important component of exposure assessment methodologies in health studies investigating impacted drinking water.