Health literacy integral to appropriate implementation of PSA screening in prostate cancer

Health literacy in men with prostate cancer was associated with both an increased likelihood that they would undergo prostate-specific antigen (PSA) screening and that their decision would not be influenced by the screening-promoting effects of shared decision making, according to a study published in Cancer.¹

For their research, the investigators evaluated the 2016 Behavioral Risk Factor Surveillance System (BRFSS) to better understand the effect of health literacy and shared decision making on the likelihood of undergoing PSA screening. It was suggested that these data are suitable for exploring this association given that several years had passed between the 2012 United States Preventive Services Task Force (USPSTF) recommendation against PSA screening and the survey data collection in 2015.

Ultimately, it was revealed that men who reported higher levels of health literacy were also more likely to have higher levels of screening.

“These findings highlight the dynamic interplay between both providers and their patients as well as between the latter’s [health literacy] and [shared decision making] that should inform the creation and promulgation of [shared decision making] guidelines, specifically when considering patients with low [health literacy],” David-Dan Nguyen, MPH, and colleagues, wrote of their findings.

Investigators assessed PSA screening in the 13 states that administered the optional Health Literacy module utilized in the BRFSS. Specifically, men aged 50 years or older who had reported their PSA-screening status were evaluated, from which the investigators identified a weighted sample of 12.249 million men with a rate of PSA screening of 33.4%.

Of the total cohort, the highest health literacy group accounted for approximately one-third (35.5%)of the study population and reported the greatest rates of PSA screening (42.2%). Thus, being in this group was deemed to be a significant predictor of undergoing PSA screening (odds ratio, 1.214)

“The discussion of the advantages and disadvantages of screening may be promoting a ‘knee-jerk’ response among patients, thereby inducing screening,” the authors explained. “However, as [health literacy] increased, the screening-promoting effect of [shared decision making] was noted to diminish in the current study.”

Upon further interaction testing between health literacy and shared decision making, the investigators observed a significant interaction between the 2 factors (P <.001), in that higher health literacy was associated with a lower likelihood of undergoing PSA screening when shared decision making was present. Maximal shared decision making remained significantly associated with a greater likelihood of PSA screening across all health literacy levels.

Limitations of the study include a survey-completion rate of 48.7% in the BRFSS, thereby making sampling error a concern. Additionally, the BRFSS did not include data regarding physician characteristics or practice environments as well as information regarding whether a patient requested screening.

Importantly, the definition of shared decision making used in this study was based on discussions of screening advantages and disadvantages with primary care providers as reported by participants. However, the definition used did not encompass all aspect of shared decision making, such as patient preference or whether patients understood their decision.

“As [shared decision making] becomes common practice, understanding how patients’ [health literacy] influences the receipt of PSA screening will play an important role in ensuring the best management of their preferences and expectations,” the authors concluded.

Reference:

1. Nguyen D, Trinh Q, Cole AP, et al. Impact of Health Literacy on Shared Decision Making for Prostate-Specific Antigen Screening in the United States. Cancer. Published November 9, 2020. doi: 10.1002/cncr.33239