TRENDS IN COLORECTAL CANCER INCIDENCE RATES IN GEORGIA BETWEEN 2000-2012

Subhendu De, Wonsuk YooInstitute of Public and Preventative Health (IPPH), Georgia Regents University

On Summer Public Health Scholars Program (SPHSP)

ABSTRACT

BACKGROUND

METHODS RESULTS

CONCLUSIONS

Colorectal cancer (CRC) is one of the major public health concerns in the United States, with estimates of 132,700 new cases and 49700 deaths occurring in 2015.

Overall incidence rates have been decreasing since the 1980s due to increased use of screening procedures and removal of pre-cancerous polyps.

Risk factors for CRC include lifestyle factors such as diet, obesity, and smoking, and family history. Overall, the Southern United States, including Georgia, suffer from higher incidence and mortality rates from CRC.

As far as we know, there is a shortage of published literatures to investigate the trends of CRC incidence rates in Georgia.

Specific Aims1. Identify trends in CRC incidence rates in Georgia compared to the

United States2. Identify differences in CRC incidence rates in Georgia based on

age, race, and gender3. Identify differences in CRC incidence rates based on geographic

location in Georgia

RESULTS

Figure 1. Trends of Age-Adjusted Incidence Rate of CRC Based on Sex in US and GA, 2000-2012

Figure 2. Trends of Age-Adjusted Incidence Rate of CRC Based on Age in US and GA, 2000-2012

RESULTS

Figure 3. Trends of Age-Adjusted Incidence Rate of CRC Based on Race in GA, 2000-2012

Figure 4. Comparison of Age-Adjusted Incidence Rate of CRC Based on Age and Race in US and GA

Figure 5. Comparison of Age-Adjusted Incidence Rate of CRC Based on Race and Geographic Location in GA

BackgroundColorectal cancer (CRC) incidence rates and mortality have been decreasing in the United States. Currently, states in the South have the smallest reduction in CRC mortality. The trends of CRC incidence rates in Georgia in comparison to the United States have not been investigated. MethodsWe analyzed age-adjusted incidence rates of CRC in Georgia and the United States from 2000 to 2012 using data from Surveillance, Epidemiology, and End Results (SEER) 18 registries. Age-adjusted incidence rates (95% Confidence Interval) were calculated as cases per 100,000 to the 2000 US Standard population. CRC incidence rates were calculated for groupings based on age at time of diagnosis, race, sex, and geographic location within Georgia. ResultsIncidence rates were higher in males compared to females in Georgia. In Georgians age 50-64, incidence rates were higher compared to the US, while those age 65+ displayed lower incidence rates. Black Georgians over 50 exhibited higher incidence rates of CRC and lower rates of decrease in incidence compared to other races in Georgia. White and black Georgians age 50-64 displayed higher incidence rates compared to the US, while Asian/Pacific Islanders Georgians displayed lower incidence rates. Greater incidence rates of CRC in rural and Greater Georgia were seen across all races when compared to overall rates in Georgia. ConclusionEfforts should be made to address disparities in Georgia based on race and geographic location. Increased screening by colonoscopy, reduction of risk factors and promotion of healthy lifestyles can reduce CRC incidence rates.

Georgia Regions (L to R)• Atlanta Metro: Clayton, Cobb, DeKalb,

Fulton, Gwinnett• Rural Georgia: Glascock, Greene,

Hancock, Jasper, Jefferson, Morgan, Putnam, Taliaferro, Warren, Washington

• Greater Georgia: All remaining counties

Analysis Methods• SEER*Stat Ver 8.2.1• Age-adjusted Incidence Rate (95% CI) as

cases per 100,000 to 2000 US Standard Population

1998 2000 2002 2004 2006 2008 2010 2012 201475

95

115

135

155

175

195

215

235

US MaleGA MaleUS FemaleGA Female

Year of Diagnosis

Inci

denc

e Ra

te

1998 2000 2002 2004 2006 2008 2010 2012 2014707580859095

100105110115

Males 50-64

USLinear (US)GALinear (GA)

Year of Diagnosis

Inci

denc

e Ra

te

1998 2000 2002 2004 2006 2008 2010 2012 201450

55

60

65

70

75

80

85

Females 50-64

USLinear (US)GALinear (GA)

Year of Diagnosis

Inci

denc

e Ra

te

1998 2000 2002 2004 2006 2008 2010 2012 2014200220240260280300320340360380

Males > 65

USLinear (US)GALinear (GA)

Year of Diagnosis

Inci

denc

e Ra

te

1998 2000 2002 2004 2006 2008 2010 2012 2014120140160180200220240260280

Females > 65

USLinear (US)GALinear (GA)

Year of Diagnosis

Inci

denc

e Ra

te

1998 2000 2002 2004 2006 2008 2010 2012 201450

100

150

200

250

300

Males > 50 in Georgia

WhiteLinear (White)BlackLinear (Black)APILinear (API)

Year of Diagnosis

Inci

denc

e Ra

te

1998 2000 2002 2004 2006 2008 2010 2012 201450

70

90

110

130

150

170

190

210Females > 50 in Georgia

WhiteLinear (White)BlackLinear (Black)APILinear (API)

Year of Diagnosis

Inci

denc

e Ra

te

White Black API White Black APIMale Female

0

20

40

60

80

100

120

140

Age 50 - 64

USGA

Inci

denc

e Ra

te

White Black API White Black APIMale Female

0

50

100

150

200

250

300

350

400

Age > 65

USGA

Inci

denc

e Ra

te

White Black API White Black APIMale Female

0

20

40

60

80

100

120

140

160

180

200

Age 50 - 64

AtlantaRural GeorgiaGreater GeorgiaGeorgia Overall

Inci

denc

e Ra

te

White Black API White Black APIMale Female

0

50

100

150

200

250

300

350

400

Age > 65

AtlantaRural GeorgiaGreater GeorgiaGeorgia Overall

Inci

denc

e Ra

te

• CRC incidence rates in Georgia are decreasing. Georgians age 50-64 have higher incidence rates compared to the US population, while Georgians age 65+ have lower incidence rates.

• In Georgians over 50, incidence rates in all demographics are decreasing. Black Georgians of both sexes have higher incidence rates compared to other races in Georgia.

• Within Georgians age 50 – 64, white and blacks have higher incidence rates compared to the US population, while Asian/Pacific Islanders have lower rates.

• White and black Georgians over 50 living in rural or Greater Georgia have higher incidence rates compared to the Georgia average.

• Numerous factors such as obesity rates, diet, access to preventive care and primary care physicians, and knowledge about screening can be implicated in the disparities seen within Georgia.