Geography of Amputations Among African Americans

描述(申请人提供)：非创伤性下肢截肢(LEA)是糖尿病的破坏性后果。65岁及以上的人约占接受非创伤性下肢截肢的糖尿病患者的50%。65岁或以上患有糖尿病的非洲裔美国人(AA)接受此类截肢的风险更高。在国际上，LEA的发病率在国家之间和国家内部存在很大的地理差异。在美国，医院转诊地区之间的比较显示出九倍的差异。没有评估LEA在较小地理区域(如县)之间差异程度的研究。这项修订的探索性研究的目的是：1)描述南部3个州65-99岁的AA和白人中糖尿病相关LEA发病率在县级的地理变异，以及2)探索选定的决定因素与3个南部3个州65-99岁的AA和白人中糖尿病相关LEA发病率的地理差异的关系。这些决定因素的选择是基于1)那些先前提出的解释LEA发病率的地理差异的因素；2)新兴的研究表明，在社会经济条件不利的地区，糖尿病患者的健康状况较差，疾病更多，手术更多，可避免的住院率更高；以及3)LEA的危险因素，无论他们的地理差异如何。研究区域是根据这3个南部州25%或更多的AA人群选择的。根据审查者的意见，我们提供了关于数据质量、有用结果的可能性以及拟议的统计分析方面的更多细节。 使用生态研究设计，将链接和分析现有的数据源，包括医疗保险索赔数据(LEA、足部溃疡、外周血管疾病、糖尿病)、服务提供者文件(医疗提供者的可用性)和2000年人口普查数据(地区社会人口统计数据)。我们将使用AA和65-99岁患有糖尿病的白人中LEA的县比率作为结果衡量标准。这项探索性研究将致力于后续更深入的研究，以确定其他潜在因素，这些因素可能决定为什么糖尿病患者在未来的RO1中特定地理区域的LEA风险增加。

DESCRIPTION (provided by applicant): Nontraumatic lower-extremity amputations (LEA) are a devastating consequence of diabetes. Persons age 65 and older account about 50% of persons with diabetes who had nontraumatic lower-extremity amputations. African Americans (AA) age 65 or older with diabetes are at increased risk of such amputations. Internationally, substantial geographic variation exists in incidence of LEAs between and within nations. In the United States, comparisons between hospital referral regions have shown nine-fold variation. Studies that have assessed the extent of the variation of LEA among smaller geographic areas, such as counties, are not available. The purpose of the revised exploratory study is to: 1) characterize the geographic variation of the incidence of diabetes-related LEA at the county level among AA and white persons age 65-99 in 3 southern states, and 2) explore the association of selected determinants with the geographic variation in diabetes-related incidence of LEA among AA and white persons age 65-99 in 3 southern states. These determinants have been selected based on 1) those previously suggested as explanation of the geographic variation that was observed in LEA rates; 2) emerging research that shows that persons in areas with adverse socioeconomic conditions have lower health status, more disease, more surgical procedures, and a higher rate of avoidable hospitalizations among persons with diabetes; and 3) risk factors for LEA regardless of their geographic variation. The study area has been selected based on the 25 percent or more AA persons in these 3 southern states. Based on the reviewers' comments, we have provided greater detail about the data quality, the likelihood of useful outcomes, and aspects about the proposed statistical analysis. Using an ecological study design, existing data sources will be linked and analyzed, including Medicare claims data (LEA, foot ulcers, peripheral vascular disease, diabetes), Provider of Services file (availability of medical providers), and the 2000 census data (area sociodemographics). We will use county-rates of LEA among AA and white persons age 65-99 with diabetes as the outcome measure. This exploratory study will serve to focus subsequent, more in-depth studies on identifying additional underlying factors that could determine why those with diabetes are at increased risk of LEA in specific geographic areas in a future RO1.