The relationship between health/disease and income/education has always been a topic of interest for me (see: Low Health Literacy and the Chance of Death; Low-Income, Uninsured Patients Often Excluded from Clinical Trials; Financial Incentives for the Pursuit of Wellness; Possible Impact on the Clinical Labs). A recent article cited research on the relationship between cancer and income (see: Your Income Might Influence Your Risk for Certain Cancers). Below is an excerpt from it:
Some cancers in the United States are tied to poverty, while others are more common among the wealthy, researchers report. In the poorest areas of the country, the incidence of cancer is generally lower than in richer regions, but deaths from cancers are higher, the study authors said.....Greater access to screening among the rich, and risky behaviors more common among the poor -- such as smoking -- may help explain the disparities, experts said. Kaposi sarcoma...and cancers of the larynx, cervix, penis and liver occur more often in the poorest neighborhoods, the investigators found. Poorer areas also had higher rates of cancers related to drinking, smoking and using injectable drugs. These are considered modifiable risk factors for cancer. Since smoking rates are higher in poor areas, so is the incidence of smoking-related cancers....Cancers tied to sexually transmitted disease and poor diet were also more likely in the poorest neighborhoods. In the wealthiest areas, thyroid and testicular cancer, melanoma and other skin cancers were more common....
For their study, the researchers used the poverty rate of the patients' neighborhoods...as a measure of socioeconomic status in 16 states and Los Angeles County....Although the researchers found scant association between poverty and cancers in general, for 32 of 39 cancers there was a significant link with economic status. Fourteen cancers were more common in poor areas and 18 were less common."Rates of cancers associated with overdiagnosis -- that is, cancers detected due to use of medical technology that would not have been identified otherwise -- tend to increase with increasing affluence," said...[one of the study authors]. Conversely, cancers common in poor areas are often the result of lack of access to cancer screening....Diagnoses of breast and prostate cancer are more common in richer areas because of greater access to screening such as mammography....Screening identifies these cancers early when they can be treated. This helps explain why poor people are more often diagnosed with advanced cancer and are more likely to die from these cancers....
Here is what I take away from the report of this research:
- "Lifestyle cancers" are more common in the poorest neighborhoods Examples include Kaplosi's sarcoma dues to AIDS, cancer of the lung and larynx due cigarette smoking, and cancer of the liver due to chronic alcoholism.
- The incidence of cancer is higher in the more affluent neighborhoods due to participation in more screening programs but cancer deaths are lower due to better access to healthcare and earlier detection.
- The avoidance of risky behaviors and healthier lifestyles leads to lower rates of certain neoplasms such as those of the larynx, cervix, penis, and liver.
- Because the affluent have more cancer screening, they have a higher incidence of certain cancers such as testicular and skin cancer including melanoma that are more often diagnosed with closer scrutiny.
- Because the affluent are screened and imaged more often, they "suffer" more from overdiagnosis. I have blogged about this topic previously (see: How to Avoid the Risks of a CT Incidentaloma; How to Explain the Surge in the Diagnosis of Cancer of the Thyroid; Sensitivity of CT Scans for the Coronary Arteries May Lead to Unnecessary Surgery).
Here's a quote from an article about environment-lifestyle cancers (see: Cancer is a Preventable Disease that Requires Major Lifestyle Changes):
Only 5–10% of all cancer cases can be attributed to genetic defects, whereas the remaining 90–95% have their roots in the environment and lifestyle. The lifestyle factors include cigarette smoking, diet (fried foods, red meat), alcohol, sun exposure, environmental pollutants, infections, stress, obesity, and physical inactivity. The evidence indicates that of all cancer-related deaths, almost 25–30% are due to tobacco, as many as 30–35% are linked to diet, about 15–20% are due to infections, and the remaining percentage are due to other factors like radiation, stress, physical activity, environmental pollutants etc. Therefore, cancer prevention requires smoking cessation, increased ingestion of fruits and vegetables, moderate use of alcohol, caloric restriction, exercise, avoidance of direct exposure to sunlight, minimal meat consumption, use of whole grains, use of vaccinations, and regular check-ups.