Neighborhood level risk factors for type 1 diabetes in youth: the SEARCH case-control study.
BACKGROUND
European ecologic studies suggest higher socioeconomic status is associated with higher incidence of type 1 diabetes. Using data from a case-control study of diabetes among racially/ethnically diverse youth in the United States (U.S.), we aimed to evaluate the independent impact of neighborhood characteristics on type 1 diabetes risk. Data were available for 507 youth with type 1 diabetes and 208 healthy controls aged 10-22 years recruited in South Carolina and Colorado in 2003-2006. Home addresses were used to identify Census tracts of residence. Neighborhood-level variables were obtained from 2000 U.S. Census. Multivariate generalized linear mixed models were applied.


RESULTS
Controlling for individual risk factors (age, gender, race/ethnicity, infant feeding, birth weight, maternal age, number of household residents, parental education, income, state), higher neighborhood household income (p = 0.005), proportion of population in managerial jobs (p = 0.02), with at least high school education (p = 0.005), working outside the county (p = 0.04) and vehicle ownership (p = 0.03) were each independently associated with increased odds of type 1 diabetes. Conversely, higher percent minority population (p = 0.0003), income from social security (p = 0.002), proportion of crowded households (0.0497) and poverty (p = 0.008) were associated with a decreased odds.


CONCLUSIONS
Our study suggests that neighborhood characteristics related to greater affluence, occupation, and education are associated with higher type 1 diabetes risk. Further research is needed to understand mechanisms underlying the influence of neighborhood context.
Department of Epidemiology and Biostatistics and Center for Research in Nutrition and Health Disparities, Arnold School of Public Health, University of South Carolina, 921 Assembly Street, Columbia, SC 29208, USA. liese@sc.edu
Angela D
AD
Liese
Robin C
RC
Puett
Archana P
AP
Lamichhane
Michele D
MD
Nichols
Dana
D
Dabelea
Andrew B
AB
Lawson
Dwayne E
DE
Porter
James D
JD
Hibbert
Ralph B
RB
D'Agostino
Elizabeth J
EJ
Mayer-Davis
D000293:Adolescent; D016022:Case-Control Studies; D002648:Child; D003120:Colorado / Q000453:epidemiology; D003922:Diabetes Mellitus, Type 1 / Q000453:epidemiology* / Q000235:genetics; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D015999:Multivariate Analysis; D011203:Poverty; D012111:Residence Characteristics; D012923:Social Class; D013022:South Carolina / Q000453:epidemiology; D013223:Statistics as Topic; D055815:Young Adult