Study of cognitive functions in breast cancer patients: A case control study

Chemotherapy-induced cognitive impairment in breast cancer survivors: A systematic review of studies from 2000 to 2021

BACKGROUND

Studies have indicated that apart from enhancing patient survival, chemotherapy has adverse side effects on the psychological, social, and cognitive functions of breast cancer survivors.

AIMS

This study was conducted to understand chemotherapy's impact on breast cancer survivors' cognitive functions.

METHODS AND RESULTS

Our study is a systematic review based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. We searched English databases, including PubMed/MEDLINE, PsycINFO, and Web of Science, and Persian databases, such as Irandoc and Elmnet, using Persian keywords of cancer, breast cancer, chemotherapy, cognitive functions, executive functions, and neuropsychological functions. Two reviewers independently evaluated the full text of the articles according to predefined criteria. Among the 937 available studies, 26 were selected based on the inclusion and exclusion criteria, of which 17 (65%) were longitudinal and 9 (35%) were cross-sectional. The findings indicated a significant relationship between the use of chemotherapy and cognitive impairments, most notably attention, working and short-term memory, and executive functions. However, the studies differed in their findings regarding the long-term persistence of cancer-related cognitive impairment (CRCI), which could be due to the wide range of tools used, different methods to measure cognitive functions, and the difference in the sample size of the studies.

CONCLUSION

Chemotherapy, affecting cortical and subcortical brain structures, causes a set of cognitive impairments that can lead to impairments in social responsibility acceptance, daily functioning, and quality of life of women. Therefore, rigorous and extensive research design is required to understand the causes and consequences of CRCI using standardized and sensitive measures of cognitive functions. Specifically, studies comparing the effects of different chemotherapy regimens on cognition and potential mechanisms and/or moderators of CRCI would be instrumental in designing more effective therapy regimens and evaluating the efficacy and cost-effectiveness of cognitive rehabilitation and supportive care programs.

Cognitive functioning and its associated factors among breast cancer patients on chemotherapy at Tikur Anbessa specialized hospital, Addis Ababa Ethiopia: an institution-based comparative cross-sectional study

BACKGROUND

Breast cancer is the second leading cause of cancer in the world. It is the commonest type of cancer in Ethiopia. Cognitive problems are common among breast cancer patients. The study aimed to assess cognitive functioning and its associated factors among breast cancer patients at Tikur Anbessa Specialized Hospital, Addis Ababa, Ethiopia 2020.

METHODS

Institution-based comparative cross-sectional study was conducted. Study subjects were 117 breast cancer patients on chemotherapy and 117 women without breast cancer who volunteered for the study. Data was collected from May-June 2020. The Mini-mental status exam (MMSE) was used to assess cognitive functioning. Data were entered into Epi Data version 4.6.0.2 and analyzed using STATA version 14 software. Univariable and multivariable linear regression model was fitted to identify factors associated with cognitive functioning. A two-tailed p-value less than 0.05 was used to declare statistical significance.

RESULTS

Among the total breast cancer patients 41.9% were diagnosed with earlier sage of the diseases (stage I and II), while the rest 58.1% were diagnosed with stage III and stage IV breast cancer. A significant difference in the MMSE score was observed among breast cancer patients and controls (19.76 ± 5.29, 25.18 ± 4.68 p <  0.0001) respectively. In multivariable linear regression analysis being non-breast cancer (Adjusted beta coefficient (Adj.β.coff). = 3.34, 95% CI (1.92-4.76) p <  0.001), hemoglobin gm/dl (Adj.β.coff =0.34, 95% CI (0.04-0.63) p = 0.02), and primary education (Adj.β.coff =2.98 95%CI (1.16-4.96) p = 0.001) secondary level and more education (Adj.β.coff = 5.47, 95%CI (3.51-7.28) p < 0.001) were significantly associated with MMSE cognitive score.

CONCLUSION

Breast cancer patients had lower mean MMSE scores when compared to non-breast cancer women. Higher hemoglobin level and higher level of education increase the MMSE cognitive score. Clinicians should incorporate routine screening of cognitive functioning for breast cancer patients and further study is required to evaluate cognitive impairment among breast cancer patients in Ethiopia.