Lack of adherence to cancer treatment using oral therapies can contribute to poor treatment outcomes, and a team of researchers conducted a study to investigate factors that may be related to lack of adherence to oral agents. Wilbur Rutter, PhD, PharmD, of CVS Health in Lincoln, Rhode Island, and colleagues presented the study’s findings in a poster at the 2022 ASCO Annual Meeting.

In this study, Dr Rutter and colleagues performed a retrospective review of records from patients with newly diagnosed multiple myeloma (MM) who were receiving treatment with oral agents during the period of September 1, 2016, through September 1, 2020. Adherence to treatment was the outcome of interest, which was defined as having an annual medication possession ratio of 0.8 to 1.2. The researchers created a socioeconomic status (SES) composite index, which was developed from data obtained at the zip-code level. They performed a multivariable regression analysis of adherence with factors including the SES-index and demographic information.

The SES-index grouped patients across 5 categories, including Very Low, Low, Medium, High, and Very High groups. It reflected increasing levels of zip code-based median household income as SES-index values rose from very low to very high. It also aligned with US Centers for Disease Control Social Vulnerability Index scores, reflecting higher vulnerability with lower SES.

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The study included 6602 patients, 64.5% of whom were considered adherent. Patients who were adherent, compared with nonadherent, differed in age (P <.00001), SES-index based on ZIP code (P =.00049), census region (P <.00001), and type of insurance (P <.00001) in unadjusted analyses.

The multivariable analysis suggested several evaluated factors showed significant, independent associations with adherence. Regarding adherence based on SES-index scores, the researchers considered patients with a very low SES-index to show a significantly lower rate of adherence than seen in patients having a very high SES-index (odds ratio [OR], 0.75; 95% CI, 0.56-1.0).

Increasing age was associated with greater adherence. With the age group of 50 to 64 years serving as a reference, patients who were 65 to 84 years of age were more likely to be adherent (OR, 1.71; 95% CI, 1.5-1.94), as were patients who were ≥85 years of age (OR, 2.11; 95% CI, 1.58-2.83). However, patients who were under 50 years of age were less likely to be adherent (OR, 0.79; 95% CI, 0.64-0.97).

Polypharmacy was associated with less adherence. Compared with lacking polypharmacy, patients with mild polypharmacy (characterized by 10-13 classes) were less likely to be adherent (OR, 0.34; 95% CI, 0.29-0.39). Moderate polypharmacy (13-18 classes) was also associated with nonadherence (OR, 0.66; 95% CI, 0.57-0.76), as was extreme polypharmacy (≥19 classes; OR, 0.46; 95% CI, 0.4-0.53).

The researchers concluded there were not significant relationships with adherence across most SES-indexes, but that patients in Very Low SES zip codes showed significantly less adherence than patients in Very High SES zip codes did. Younger age and polypharmacy were other factors they considered linked to worse adherence.

Disclosures: Some authors have declared affiliations with or received grant support from the pharmaceutical industry. Please refer to the original study for a full list of disclosures.


Rutter W, Prakash S, Cavers W, et al. Association of socioeconomic status with adherence to oral agents in patients with multiple myeloma. Presented at ASCO 2022; June 3-7, 2022. Abstract 8023.