Low Literacy Predicts Advanced Prostate Cancer Presentation

October 1, 1998
Terry C. Davis, PhD

A. Oliver Sartor, MD

Charles L. Bennett, MD, PhD

Oncology NEWS International, Oncology NEWS International Vol 7 No 10, Volume 7, Issue 10

Prostate cancer is the most common cancer in the United States, with an estimated 200,000 new cases diagnosed in 1998.[1] Compared with white men, African-American men have a 66% higher incidence of prostate cancer and mortality rates twice as high.[1]

Prostate cancer is the most common cancer in the United States, with an estimated 200,000 new cases diagnosed in 1998.[1] Compared with white men, African-American men have a 66% higher incidence of prostate cancer and mortality rates twice as high.[1]

Widespread use of PSA testing has led to a 50% increase in the incidence of prostate cancer from 1989 to 1993, as well as an increased frequency and proportion of early stage prostate cancer diagnoses. There is, however, concern that improvements in care for African-American men are not as great as for white men. Moreover, there are debates whether these improvements in prostate cancer care are associated with lower mortality.[2] This lack of data about the efficacy of prostate cancer screening has led to uncertainty over whether routine PSA testing should be recommended for whites, African-Americans, and other racial/ethnic minorities.[3]

Barriers to Screening

While the debate over widespread use of PSA for routine prostate cancer screening continues, it is apparent that there are many economic and sociocultural barriers to screening. Moreover, these barriers are likely to differ across racial/ethnic groups.[4-6]

For example, lack of access to screening and early detection programs among African-American men is one factor associated with later stages of prostate cancer at presentation. Also, African-American men with low income may not be able to afford PSA screening, which is not covered by Medicare. Finally, African-Americans often are reluctant to participate in screening programs, because of concerns over the potential benefits.[4]

Poor literacy skills are thought to be another potential factor in explaining racial variations in medical care and outcomes for cancer patients.[5,6] African-Americans with lower educational levels may lack adequate knowledge of screening and early cancer detection efforts. Educational materials about screening and early detection are often written at a literacy level well above that of a significant portion of the US population.[7]

It is estimated that 48% of the adult US population have insufficient literacy skills, with 23 million adults being functionally illiterate.[8] Among low income African-American men, the elderly are particularly affected by low literacy

barriers.[9] One study of low income minority individuals found an 81% prevalence of inadequate or marginal functional health literacy among individuals who were over age 60, compared with 19% for those aged 18 to 30.[9]

We conducted a study to evaluate how the incidence of advanced stage prostate cancer at presentation is associated with literacy skills and race among low income older men.[10] Our study population consisted of 212 English-speaking men treated at prostate cancer clinics in Chicago and Shreveport, Louisiana, over a 6-month period in 1996 and 1997.

All of the Chicago patients were treated at the Chicago VA Healthcare System/Lakeside Division, while two thirds of the Shreveport patients were treated at the Overton-Brooke VA Medical Center, and one third received care at a univer-sity hospital that provides care to low income patients who are uninsured or who are covered by Medicaid. Both health settings are part of equal access systems, treating primarily low income patients.

We assessed patients’ literacy levels with a validated instrument, the Rapid Estimate of Adult Literacy in Medicine (REALM).[11] The REALM is an individually administered medical word recognition and pronunciation test, comprised of 66 words that patients are expected to know in order to participate effectively in their own health care. It was designed for evaluating adult reading ability in the medical setting and is an indicator of functional literacy skills.[11]

Raw REALM scores can be converted into four reading grade levels; 0-3rd grade, 4th-6th grade, 7th-8th grade, and 9th grade and above. The REALM can be administered and scored in 1 to 3 minutes.[11] In addition to REALM scores, we obtained information from medical records on patient age, race/ethnicity, and pathologic stage.

Of the 212 men in the study, 155 were from Shreveport and 57 from Chicago. The mean age of the group was 70.8 years. Patients were almost equally divided into two racial groups: African-American and white. Patients varied in age, with 22.6% under 65 years of age, 45.8% between 65 and 74, and 31.6% age 75 or older.

Study Results

Literacy differed by stage, race, and site of care, but not by age. Men with metastatic cancer at presentation were 1.5 times more likely to have lower literacy levels (39.6% of patients with stage D disease had literacy levels of 6th grade or below vs 24.8% of stage A to C patients, P < .001). African-American men were more likely to have lower literacy levels (52.3% had levels of 6th grade or below vs 8.7% of whites, P < .001).

When we evaluated predictors of late stage prostate cancer at presentation, we found higher rates related to two factors: literacy levels lower than 6th grade (54.5% vs 37.7%, P = .02) and African-American race/ethnicity (49.5% vs 35.9%, P < .05).

City and older age were not significant univariate predictors of advanced stage prostate cancer at presentation. However, in a multivariate regression model (after adjustment for literacy level, geographic location, and age), race was no longer a significant predictor of advanced stage of disease at presentation (odds radio = 1.4; 95% CI = 0.7,2.7).

Race Not Significant Predictor

These results suggest that differences in literacy are likely to be an important and often overlooked factor to consider when evaluating differences in stage at presentation among different socioeconomic and racial groups. In this study of low income older men, after adjustment for differences in literacy levels, race was not a significant predictor of advanced stage of prostate cancer at presentation.

Low literacy skills may be an important factor in explaining advanced stage of prostate cancer at presentation for both white and African-American men.[2,4-6] Low income, low literacy men may not be aware of the possibility of undergoing prostate cancer screening and the availability of screening programs at churches, schools, clinics, county hospitals, and VA medical centers. Previous research has shown that poor literacy skills are an important factor associated with low usage of preventive health services and with knowledge and understanding of an individual’s medical illnesses.[12]

Several aspects of this study should be highlighted. First, a specific evaluation is required to assess literacy skills. The REALM is an easily and rapidly administered test to formally assess literacy.[11] It has been shown that patient self-reports of educational level are not a good indicator of literacy skills for medical information.[9] Patients are reluctant to admit to poor reading skills and may not be familiar with medical terminology. Moreover, standardized tests may overestimate a patient’s ability to read and comprehend medical passages.[13-15]

Second, patients such as those in our study who are treated in equal access health systems and have guaranteed financial access to care may still face cultural, social, and personal barriers to medical care.[9]

Relevance to Clinicians

The findings of this pilot study on medical literacy and prostate cancer, as well as those of larger studies, are relevant to practitioners.[7,16] Given that an estimated 48% of US adults have insufficient literacy skills and that many, if not most, medical educational materials are written at the high school or college level, a large portion of patients may not understand this information.[7]

Efforts to improve this situation include a randomized controlled trial, initiated by ECOG, to evaluate low literacy consent forms in the clinical trial setting. The Save our Sisters Projects for increasing mammography use is an example of a program that includes culturally appropriate, easily understandable educational materials.

Patient education is unlikely to be successful as a single intervention. Medical information, written or audiovisual, must be developed so as to be easily understood by patients, family members, and peers. In addition, culturally sensitive, low literacy educational materials, developed with the input of the target population, may improve patient awareness of prostate cancer. Ultimately, these interventions may lead to a decrease in the incidence of advanced stage prostate cancer. w


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