Linking the Iowa Women's Health Study cohort to Medicare data: linkage results and application to hip fracture.

This study linked the Iowa Women's Health Study cohort to Medicare administrative data and assessed the value of using Medicare and survey-based sources to study hip fracture incidence. The authors used Social Security number to combine the Iowa Women's Health Study cohort Medicare enrollment and claims data for 1986-2004. Hip fractures were identified from Medicare and follow-up-mail, survey-based sources. Estimates of hip fracture incidence after age 65 years and postfracture mortality were compared. The authors were able to match to Medicare 99.2% of the 40,978 Iowa Women's Health Study participants who survived to age 65 years. Although both Medicare and survey-based hip fracture incidence showed the expected positive association with age and negative association with body mass index, hip fracture incidence was considerably underestimated by self-report (2.61 per 1,000 person-years of observation vs. 4.20 per 1,000 person-years of observation from Medicare-based estimates). Similarly, 1-year postfracture mortality was significantly underestimated by survey-based measures (1% vs. 14% for Medicare-based estimates). Medicare data are an outstanding source of health care information to supplement for older cohorts that have identifiers such as Social Security numbers. These data are useful for studying clinically unambiguous and high morbidity and mortality conditions. They enable less-biased collection of health data.

Correlates and consequences of venous thromboembolism: The Iowa Women's Health Study.

OBJECTIVES: We sought to document incidence, case-fatality, and recurrence rates of venous thromboembolism (VTE) in women and to explore the relationship of demographic, lifestyle, and anthropometric factors to VTE incidence. METHODS: Data from participants aged 55 to 69 years in the Iowa Women's Health Study were linked to Medicare data for 1986 through 2004 (n = 40 377) to identify hospitalized VTE patients. RESULTS: A total of 2137 women developed VTE, yielding an incidence rate of 4.04 per 1000 person-years. The 28-day case-fatality rate was 7.7%, and the 1-year recurrence rate was 3.4%. Educational attainment, physical activity, and age at menopause were inversely associated with VTE. Risk of secondary (particularly cancer-related) VTE was higher among smokers than among those who had never smoked. Body mass index, waist circumference, waist-to-hip ratio, height, and diabetes were positively associated with VTE risk. Hormone replacement therapy use was associated with increased risk of idiopathic VTE. CONCLUSIONS: VTE is a significant source of morbidity and mortality in older women. Risk was elevated among women who were smokers, physically inactive, overweight, and diabetic, indicating that lifestyle contributes to VTE risk.

Risk of dementia in older breast cancer survivors: a population-based cohort study of the association with adjuvant chemotherapy.

OBJECTIVES: To assess whether there is an association between delivery of adjuvant chemotherapy to older women with breast cancer and development of dementia over time. DESIGN: Retrospective cohort study using Surveillance, Epidemiology, and End Results (SEER) data linked to Medicare claims data. SETTING: Women residing in geographic areas included in the SEER registry. PARTICIPANTS: Women aged 66 to 80 diagnosed with non-metastatic invasive breast cancer from 1992 to 1999 were included. It was determined whether patients had undergone chemotherapy within 6 months of diagnosis. MEASUREMENTS: Whether women developed dementia over time was determined using diagnostic codes. The effect of adjuvant chemotherapy on development of dementia was evaluated, adjusting for confounders using a proportional hazards model stratified for age. RESULTS: Twenty-one thousand three hundred sixty-two women met selection criteria; 2,913 received chemotherapy, and 18,449 did not. Women who received chemotherapy were younger than those who did not (median aged 70 vs 73; P<.001). Median follow-up time was 59 months. After controlling for other factors, it was found that chemotherapy was not associated with a greater risk of development of dementia over time for any age group (hazard ratio for dementia in women receiving chemotherapy: aged 66-70=0.83, 95% confidence interval (CI)=0.48-1.45, P=.5; aged 71-75=0.74, 95% CI=0.46-1.18, P=.2; aged 76-80=0.49, 95% CI=0.28-0.88, P=.02). CONCLUSION: Receipt of chemotherapy in older women with breast cancer was not associated with a greater risk of dementia diagnosis over time; very elderly women who undergo chemotherapy may be at lower baseline risk. The use of a claims-based definition of dementia limited the study.

Managed care enrollment and chronically disabled women with breast cancer.

OBJECTIVE: To assess whether managed care enrollment or healthcare utilization level among women enrolled in Medicare because of disability affects stage at diagnosis and treatment of breast cancer. STUDY DESIGN: Retrospective study using the Surveillance, Epidemiology, and End Results-Medicare database. We compared breast cancer stage at diagnosis and treatment among women with disabilities enrolled in Medicare managed care versus fee-for-service (FFS) Medicare. Women enrolled in FFS Medicare were classified into levels of healthcare utilization during the 6 to 18 months before breast cancer diagnosis. METHODS: Controlling for confounders, we used regression models to determine the effects of managed care enrollment and healthcare utilization level on earlier stage at diagnosis and treatment of breast cancer. RESULTS: Disabled patients enrolled in FFS Medicare without contact with the healthcare system and those with fewer than 12 physician visits during the 6 to 18 months before breast cancer diagnosis were more likely than disabled patients enrolled in Medicare managed care to be diagnosed as having breast cancer at a late stage. There was no difference between women enrolled in Medicare managed care versus women enrolled in FFS Medicare having at least 12 physician visits during the 12-month period. Breast cancer treatment for women with disabilities did not vary across managed care enrollment or healthcare utilization level. CONCLUSION: Managed care enrollment or increased contact with healthcare providers could result in earlier stage at breast cancer diagnosis.

Geographic variation in device use for intertrochanteric hip fractures.

BACKGROUND: Hip fractures in the elderly are a common and costly problem, with intertrochanteric fractures accounting for almost half of these fractures. Most intertrochanteric fractures are treated with either a plate-and-screw device or an intramedullary nail device. We assessed the degree of geographic variation in use of intramedullary nailing for intertrochanteric femoral fractures among Medicare beneficiaries between 2000 and 2002. METHODS: Medicare 100% files (hospital and physician claims, and enrollment) for 2000 through 2002 were used to identify beneficiaries, sixty-five years of age or older, who had undergone inpatient surgery for the treatment of an intertrochanteric femoral fracture with a plate-and-screw device or an intramedullary nail. We used multiple logistic regression analysis to model the use of an intramedullary nail (as opposed to a plate-and-screw device) by state and year, after adjusting for patient age, sex, race, subtrochanteric fracture, comorbidities, and Medicaid-administered assistance. The odds ratios of receiving an intramedullary nail device are reported. The adjusted state rates of intramedullary nailing per 100 Medicare patients with an intertrochanteric fracture are reported for 2000 through 2002. RESULTS: In this study, 212,821 claims for operations to treat patients with an intertrochanteric fracture from 2000 through 2002 met the inclusion criteria. There was considerable geographic variation in intramedullary nail use by state across all years. The mean adjusted intramedullary nailing rate per 100 Medicare patients with an intertrochanteric fracture increased nationally from 7.84 in 2000 to 16.98 in 2002. In 2000, surgeons in sixteen states used an intramedullary nail in fewer than one of every twenty Medicare patients with an intertrochanteric fracture. By 2002, surgeons in only two states used an intramedullary nail in fewer than one of every twenty patients with an intertrochanteric fracture, and in eight states they used an intramedullary nail in more than one of every four patients with an intertrochanteric fracture. CONCLUSIONS: There was substantial geographic variation in the use of intramedullary nailing by state from 2000 through 2002 that was largely not explained by patient-related factors.

Medicare-certified home health care: urban-rural differences in utilization.

CONTEXT: Availability of Medicare-certified home health care (HHC) to rural elders can prevent more expensive institutional care. To date, utilization of HHC by rural elders has not been studied in detail. PURPOSE: To examine urban-rural differences in Medicare HHC utilization. METHODS: The 2002 100% Medicare HHC claims and denominator files were used to estimate use of HHC and to make urban-rural comparisons on the basis of utilization levels within ZIP codes. FINDINGS: Overall, the proportion of Medicare beneficiaries living in areas with little HHC utilization is relatively low. Rural elders, however, are more likely than their urban counterparts to live in such areas. Less than 1% of urban beneficiaries live in ZIP codes with no or low use of HHC, but over 17% of the most rural beneficiaries live in such areas. CONCLUSIONS: Continued monitoring of rural HHC utilization and access is important, especially as Medicare seeks to evaluate the effectiveness of payment increases to rural home health agencies.

Postoperative irradiation for rectal cancer increases the risk of small bowel obstruction after surgery.

OBJECTIVE: To determine the risk of small bowel obstruction (SBO) after irradiation (RT) for rectal cancer BACKGROUND: : SBO is a frequent complication after standard resection of rectal cancer. Although the use of RT is increasing, the effect of RT on risk of SBO is unknown. METHODS: We conducted a retrospective cohort study using Surveillance, Epidemiology, and End Results cancer registry data linked to Medicare claims data to determine the effect of RT on risk of SBO. Patients 65 years of age and older diagnosed with nonmetastatic invasive rectal cancer treated with standard resection from 1986 through 1999 were included. We determined whether patients had undergone RT and evaluated the effect of RT and timing of RT on the incidence of admission to hospital for SBO, adjusting for potential confounders using a proportional hazards model. RESULTS: We identified a total of 5606 patients who met our selection criteria: 1994 (36%) underwent RT, 74% postoperatively. Patients were followed for a mean of 3.8 years. A total of 614 patients were admitted for SBO over the study period; 15% of patients in the RT group and 9% of patients in the nonirradiated group (P < 0.001). After controlling for age, sex, race, diagnosis year, type of surgery, and stage, we found that patients who underwent postoperative RT were at higher risk of SBO, hazard ratio 1.69 (95% CI, 1.3-2.1). However, the long-term risk associated with preoperative irradiation was not statistically significant (hazard ratio, 0.89; 95% CI, 0.55-1.46). CONCLUSIONS: Postoperative but not preoperative RT after standard resection of rectal cancer results in an increased risk of SBO over time.

Trends in the incidence of invasive and in situ vulvar carcinoma.

OBJECTIVE: To characterize the incidence of vulvar carcinoma in situ and vulvar cancer over time. METHODS: We used the Surveillance Epidemiology and End Results database to assess trends in the incidence of vulvar cancer over a 28-year period (1973 through 2000) and determined whether there had been a change in incidence over time. Information collected included patient characteristics, primary tumor site, tumor grade, and follow-up for vital status. We calculated the incidence rates by decade of age, used chi(2) tests to compare demographic characteristics, and tested for trends in incidence over time. RESULTS: A total of 13,176 in situ and invasive vulvar carcinomas were identified; 57% of the women were diagnosed with in situ, 44% with invasive disease. Vulvar carcinoma in situ increased 411% from 1973 to 2000. Invasive vulvar cancer increased 20% during the same period. The incidence rates for in situ and invasive vulvar carcinomas are distributed differently across the age groups. In situ carcinoma incidence increases until the age of 40-49 years and then decreases, whereas invasive vulvar cancer risk increases as a woman ages, increasing more quickly after 50 years of age. CONCLUSION: The incidence of in situ vulvar carcinoma is increasing. The incidence of invasive vulvar cancer is also increasing but at a much lower rate.

Risk of pelvic fractures in older women following pelvic irradiation.

CONTEXT: Pelvic fractures, including hip fractures, are a major source of morbidity and mortality in older women. Although therapeutic pelvic irradiation could increase the risk of such fractures, this effect has not been studied. OBJECTIVE: To determine if women who undergo pelvic irradiation for pelvic malignancies (anal, cervical, or rectal cancers) have a higher rate of pelvic fracture than women with pelvic malignancies who do not undergo irradiation. DESIGN, SETTING, AND PARTICIPANTS: We conducted a retrospective cohort study using Surveillance, Epidemiology, and End Results (SEER) cancer registry data linked to Medicare claims data. A total of 6428 women aged 65 years and older diagnosed with pelvic malignancies from 1986 through 1999 were included. We compared results for women who did (n = 2855) vs did not (n = 3573) undergo radiation therapy. To assess the influence of selection bias, we also evaluated the effect of irradiation on osteoporotic fractures in nonirradiated sites (arm and spine). MAIN OUTCOME MEASURE: We evaluated the effect of irradiation on the incidence of pelvic fractures over time, and adjusted for potential confounders using a proportional hazards model. RESULTS: Women who underwent radiation therapy were more likely to have a pelvic fracture than women who did not undergo radiation therapy (cumulative 5-year fracture rate, 14.0% vs 7.5% in women with anal cancer, 8.2% vs 5.9% in women with cervical cancer, and 11.2% vs 8.7% in women with rectal cancer); the difference was statistically significant and most fractures (90%) were hip fractures. We controlled for potential confounders including age, race, cancer stage, and geographic location. The impact of irradiation varied by cancer site: treatment for anal cancer was associated with a higher risk of pelvic fractures (hazard ratio, 3.16; 95% confidence interval, 1.48-6.73); than for cervical cancer (hazard ratio, 1.66; 95% confidence interval, 1.06-2.59); or rectal cancer (hazard ratio, 1.65; 95% confidence interval, 1.33-2.05). No statistically significant difference was found in the rate of arm or spine fractures between the irradiated and nonirradiated groups (hazard ratio, 1.15; 95% confidence interval, 0.89-1.48). CONCLUSIONS: Pelvic irradiation substantially increases the risk of pelvic fractures in older women. Given the high baseline risk of pelvic fracture, this finding is of particular concern.

Providing hospice care in rural areas: challenges and strategies.

Hospices in rural settings face challenges in the provision of hospice care as a result of their location and the size of their service area population. To ascertain the challenges that hospices face in serving rural communities, researchers conducted in-depth case studies of four different models of hospice care in rural areas. The authors describe strategies used by the case study hospices and recommend policies that could increase access to hospice care for rural Medicare beneficiaries and other rural residents. National initiatives to improve end-of-life care need to consider the special challenges faced by rural hospices.

Increased risk of rectal cancer after prostate radiation: a population-based study.

BACKGROUND & AIMS: Radiation therapy for prostate cancer has been associated with an increased rate of pelvic malignancies, particularly bladder cancer. The association between radiation therapy and colorectal cancer has not been established. METHODS: We conducted a retrospective cohort study using Surveillance, Epidemiology, and End Results (SEER) registry data from 1973 through 1994. We focused on men with prostate cancer, but with no previous history of colorectal cancer, treated with either surgery or radiation who survived at least 5 years. We evaluated the effect of radiation on development of cancer for 3 sites: definitely irradiated sites (rectum), potentially irradiated sites (rectosigmoid, sigmoid, and cecum), and nonirradiated sites (the rest of the colon). Using a proportional hazards model, we evaluated the effect of radiation on development of colorectal cancer over time. RESULTS: A total of 30,552 men received radiation, and 55,263 underwent surgery only. Colorectal cancers developed in 1437 patients: 267 in irradiated sites, 686 in potentially irradiated sites, and 484 in nonirradiated sites. Radiation was independently associated with development of cancer over time in irradiated sites but not in the remainder of the colon. The adjusted hazards ratio for development of rectal cancer was 1.7 for the radiation group, compared with the surgery-only group (95% CI: 1.4-2.2). CONCLUSIONS: We noted a significant increase in development of rectal cancer after radiation for prostate cancer. Radiation had no effect on development of cancer in the remainder of the colon, indicating that the effect is specific to directly irradiated tissue.

Do rural elders have limited access to Medicare hospice services?

OBJECTIVES: To examine whether there are urban-rural differences in use of the Medicare hospice benefit before death and whether those differences suggest that there is a problem with access to hospice care for rural Medicare beneficiaries. DESIGN: Observational study using 100% of Medicare enrollment, hospice, and hospital claims data. SETTING: Inpatient hospitals and hospices. PARTICIPANTS: Persons aged 65 and older in the Medicare program who died in 1999. MEASUREMENTS: Rates of hospice use before death and in-hospital death rates were calculated. RESULTS: In 1999, there were 1.76 million deaths of Medicare beneficiaries aged 65 and older. Hospice services were used by 365,700 of these beneficiaries. Rates of hospice care before death were negatively associated with degree of rurality. The lowest rate of hospice use, 15.2% of deaths, was seen in rural areas not adjacent to an urban area. The highest rate of use, 22.2% of deaths, was seen in urban areas. Rural areas adjacent to urban areas had an intermediate level of hospice use (17.0% of deaths). Hospices based in rural areas had a smaller number of elderly patients each year than hospices based in urban areas (P<.001) and were more likely to have very low volumes (average daily census of three patients or less). CONCLUSION: The consistently lower use of Medicare hospice services before death and smaller sizes of rural hospices suggest that the combination of Medicare hospice payment policies and hospice volumes are problematic for rural hospices. Adjusting Medicare payment policies might be a critical step to assure availability of hospice services forterminally ill beneficiaries regardless of where they live.

Trends in the treatment of ductal carcinoma in situ of the breast.

BACKGROUND: An increase in incidence of ductal carcinoma in situ (DCIS) of the breast has been documented, and concerns regarding overly aggressive treatment have been raised. This study was designed to evaluate the use of surgery and radiation therapy in treating DCIS. METHODS: We used the National Cancer Institute's Surveillance, Epidemiology, and End Results database to assess treatment of patients with DCIS with no evidence of microinvasion who were diagnosed from January 1, 1992, through December 31, 1999. We assessed the rates of mastectomy, breast reconstruction, radiation therapy after lumpectomy, and axillary dissection. Associations were analyzed by logistic regression. RESULTS: During the study period, 25 206 patients met selection criteria. The incidence of DCIS dramatically increased with time; however, the incidence of comedo lesions did not change. The rate of mastectomy decreased from 43% in 1992 to 28% in 1999, after controlling for age, race, tumor size, comedo histology, and geographic location. However, because of the increase in the diagnosis of DCIS, the age-adjusted incidence of mastectomy for DCIS in the population did not change (7.8 per 100 000 women in 1992 and 1999). Almost half the patients undergoing lumpectomy did not undergo radiation therapy (55% in 1992 and 46% in 1999); in those with comedo histology, 33% did not undergo radiation therapy after lumpectomy, even in 1999. Overall, patients were less likely to have axillary dissection over time (34% in 1992 versus 15% in 1999), yet the rate of axillary dissection was still high (30%) in patients undergoing mastectomy in 1999. Large, statistically and clinically significant variation by geographic location was found in treatment. CONCLUSIONS: Treatment of DCIS changed in a clinically significant fashion between 1992 and 1999. Throughout this study, many patients were found to undergo aggressive surgical therapy, including mastectomy and axillary dissection, whereas others appeared to be undertreated, e.g., not receiving radiation therapy after lumpectomy, even in the presence of adverse histologic features. Variation in demographic and geographic factors indicates that at least some of these treatment differences reflect individual and institutional practice patterns that may be modifiable.

Further experience with gastric stimulation to treat drug refractory gastroparesis.

BACKGROUND: Gastric electrical stimulation (GES) has been introduced for patients with gastroparesis refractory to pharmacological therapy. METHODS: From April 1998 until November 2001, 55 patients underwent GES implantation at Kansas University Medical Center. All patients had prolonged gastric retention of a solid meal by scintigraphy at baseline. The etiologies were diabetes mellitus in 39, related to previous surgery in 9, and idiopathic in 7. Symptoms were graded using a 5-point scale and quality of life was assessed with the SF-36 questionnaire. Body mass index and nutritional parameters were monitored. Hemoglobin A1C was measured in the diabetic patients. RESULTS: Total symptom scores and the physical and mental composite scores of quality of life improved significantly. On average, gastric emptying did not change. Body mass index and body weight increased significantly. And days spent in hospital admissions were significantly decreased. At 1 year, diabetic patients experienced reduced hemoglobin A1C. Four devices were removed. One patient died of a pulmonary embolus postoperatively. CONCLUSIONS: In a large series of patients with gastroparesis, GES significantly improved symptoms and quality of life.