Racial disparities of pancreatic cancer in Georgia: a county-wide comparison of incidence and mortality across the state, 2000-2011

Abstract

Understanding the geographic distribution of pancreatic cancer is important in assessing disease burden and identifying high-risk populations. This study examined the geographic trends of pancreatic cancer incidence, mortality, and mortality-to-incidence ratios (MIRs) in Georgia, with a special focus on racial disparities of disease. Directly age-adjusted pancreatic cancer incidence and mortality rates for Georgia counties (N = 159) were obtained for 2000-2011. Maps of county age-adjusted disease rates and MIRs were generated separately for African Americans and Caucasians. Cluster analyses were conducted to identify unusual geographic aggregations of cancer cases or deaths. Pearson correlation coefficients were calculated to examine associations between county health factors (e.g., health behaviors, clinical care, and physical environment) and pancreatic cancer incidence or mortality rates. African Americans displayed a significantly higher age-adjusted incidence (14.6/100,000) and mortality rate (13.3/100,000), compared to Caucasians. Cluster analyses identified five significant incidence clusters and four significant mortality clusters among Caucasians; one significant incidence cluster and two significant mortality clusters were identified among African Americans. Weak but significant correlations were noted between physical environment and pancreatic cancer incidence (ρ = 0.16, P = 0.04) and mortality (ρ = 0.18, P = 0.02) among African Americans. A disproportion burden of pancreatic cancer incidence and mortality was exhibited among African Americans in Georgia. Disease intervention efforts should be implemented in high-risk areas, such as the southwest and central region of the state. Future studies should assess health behaviors and physical environment in relationship with the spatial distribution of pancreatic cancer.

Keywords: Cluster analysis; pancreatic cancer; racial disparities.

Figure 1

Georgia age‐adjusted pancreatic cancer rates by time and race, 2000–2011. Rates are per 100,000 and age‐adjusted to the 2000 US Standard Population. Data Source: SEER*Stat (version 8.1.5).

Figure 2

Pancreatic cancer mortality‐to‐incidence ratios (MIRs) by race and county, 2000–2011. Rates used to calculate MIRs are per 100,000 and age‐adjusted to the 2000 US Standard Population. Data Source: SEER*Stat (version 8.1.5). *Includes Caucasian, African American, American Indian/Alaska native, Asian or Pacific Islander, and unknown race.

Figure 3

Age‐adjusted pancreatic cancer incidence rates and clusters of pancreatic cancer incidence cases by race and county, 2000–2011. Note: Pancreatic cancer incidence clusters are numbered and indicated by black county shading. Numbers correspond to the cluster numbers in Table 2. Further details on each cluster can be found in Table 2. Note: Primary clusters are considered significant at P ≤ 0.05. Secondary clusters are considered significant at P ≤ 0.01. SaTScan Parameters: Discrete Poisson model, 3% Spatial Scanning Window, 999 simulations. Data Source: SEER*Stat (version 8.1.5). Rates are per 100,000 and age‐adjusted to the 2000 US Standard Population. *Includes Caucasian, African American, American Indian/Alaska native, Asian or Pacific Islander, and unknown race.

Figure 4

Age‐adjusted pancreatic cancer mortality rates and clusters of pancreatic cancer mortality cases by race and county, 2000–2011. Note: Pancreatic cancer mortality clusters are numbered and indicated by black county shading. Numbers correspond to cluster numbers in Table 2. Further details on each cluster can be found in Table 2. Note: Primary clusters are considered significant at P ≤ 0.05. Secondary clusters are considered significant at P ≤ 0.01. SaTScan Parameters: Discrete Poisson model, 3% Spatial Scanning Window, 999 simulations. Data Source: SEER*Stat (version 8.1.5). Rates are per 100,000 and age‐adjusted to the 2000 US Standard Population. *Includes Caucasian, African American, American Indian/Alaska native, Asian or Pacific Islander, and unknown race.