The association between antiretroviral therapy adherence following cancer diagnosis and survival outcomes in people living with HIV and cancer in Shanghai, China

Background The impact of antiretroviral therapy (ART) adherence following cancer diagnosis on survival outcomes among people living with HIV (PLWH) with cancer remains unclear. Methods We conducted a retrospective study among PLWH with cancer from a major infectious disease hospital in Shanghai, China. Cox proportional hazards models were used to investigate factors associated with all-cause mortality among PLWH with cancer, with a particular emphasis on ART adherence following cancer diagnosis. ART adherence was measured as the proportion of days covered (PDC) by antiretroviral drugs, and in the primary analysis, patients’ ART adherence was dichotomized using an 80% threshold. Furthermore, we conducted sensitivity analyses, adjusting the cutoff values for adherence rates (85%, and 90%). Results A total of 428 PLWH with cancer (355 [82.9%] male, median age at cancer diagnosis 51.84[IQR, 37.02-59.62]) were included, comprising 131 cases of AIDS-defining cancers (ADCs) and 297 non-AIDS-defining cancers (NADCs). The median ART adherence following cancer diagnosis was 87.7% (IQR, 69.6%-96.0%). In multivariate analyses, lower ART adherence (<80%) after cancer diagnosis was independently associated with an increased risk of death (HR=2.03, P <0.001). By contrast, none of the HIV immunovirological status variables measured at cancer diagnosis showed a significant association with increased mortality. Similar patterns were observed across cancer subgroups, including ADCs, NADCs, and lymphomas. Conclusions ART adherence following cancer diagnosis is essential to survival among PLWH with cancer. The integration of ART adherence support in HIV routine care may contribute to improved survival outcomes in PLWH with cancer.