Cognitive problems of breast cancer survivors on proton pump inhibitors

PURPOSE: Proton pump inhibitors (PPIs) are used in cancer patients to manage treatment-related gastrointestinal symptoms and to prevent damage to the gastric mucosal lining during treatment. However, PPI use may contribute to cognitive problems. To compare PPI-users and non-users, breast cancer survivors reported cognitive problems in three studies. METHODS: In Study 1, breast cancer survivors (N=209; n=173 non-users, n=36 PPI-users; stages 0-IIIC) rated their cognitive function on the Kohli scale prior to cancer treatment, as well as one and two years later. In Study 2, women (N=200; n=169 non-users, n=31 PPI-users, stages 0-IIIa, M=11 months post-treatment) rated their cognitive function on the Kohli scale and BCPT checklist at three visits over a six-month period. In Study 3, participants (N=142; n=121 non-users, n=21 PPI-users; stages I-IIIa, M=4 years post-treatment) rated their cognitive function on the Kohli scale, BCPT checklist, and Functional Assessment of Cancer Therapy cognitive scale (FACT-cog). RESULTS: In Study 1, PPI-users reported more severe concentration problems (p=0.039) but not memory problems (p=0.17) than non-users. In Study 2, PPI-users reported more severe concentration problems (p=0.022) than non-users, but not memory problems or symptoms on the BCPT (ps=0.11). Study 3’s PPI-users reported more severe memory problems (p=0.002), poorer overall cognitive function (p=0.006), lower quality of life related to cognitive problems (p=0.005), greater perceived cognitive impairment (p=0.013), and poorer cognitive abilities (p=0.046), but not more severe concentration problems (p=0.16), compared to non-users. CONCLUSIONS/IMPLICATIONS: PPI use may impair breast cancer survivors’ memory, concentration, and quality of life.