This study aimed to assess cognitive functioning and associated factors among breast cancer patients and healthy controls using the MMSE score as an assessment tool. The MMSE is a widely used tool for assessing cognitive impairment. It demonstrates a moderately high level of reliability and it is easy to administer which makes it suitable to use in resource-limited situations (16).
In our study mean MMSE score of breast cancer patients was significantly lower when compared to healthy controls. This is ln line with other studies conducted in India(17) and Greece (18). Additionally, breast cancer patients had significantly lower scores in the domains of cognition including orientation, memory, attention, and language this is in agreement with a study by Ando-Tanabe and colleagues(12).
Based on the categories recommended by Folestien and colleagues, the overall prevalence of cognitive impairment among breast cancer patients in the current study was 47%, which is higher than studies conducted in Greece, US, and France which reported prevalence of cognitive impairment among breast cancer patients as 28%, 35% and 15%(18–20). The difference can be justified by differences in demographical background, differences in the method of assessing cognitive impairment, and differences in disease or treatment status of the patients(21).
Unlike other studies, in the current study, there was no association between MMSE cognitive score and the number of chemotherapy cycles taken, type of chemotherapy regimen, and the stage of breast cancer(21–23). This may be due to differences in the method of cognitive assessment used and the difference in disease and treatment status of the patients.
The effect of education on cognitive scores have been described by different literature. Educational experience may provide the necessary knowledge and skill that enhance participation in cognitively demanding activities(24,25). In the current study, higher level of education was found to be a significant positive predictor of higher cognitive performance which is in agreement with other studies (26–28).
Aging causes neurophysiological and neuroanatomical changes in the brain which leads to changes in cognitive performance(29). In the current study, there was no association between age and cognitive changes. This was against studies that found age as one of the negative predictors for cognitive performance(30,31). The reason may be due to the fact that most of women in our study were in the younger age group.
Estrogen influences neurogenesis and neurotransmitter modulation, neuronal injury, and repair in different parts of the brain that are mainly involved in cognition(32). Different studies have shown estrogen reduction due to menopause is associated with cognitive impairment(33). In the current study, there was no significant association between menopause and cognitive impairment which, is in line with a study in the US but different from a study by Amin and colleagues which showed a significant association between menopause and cognitive impairment(20)(34). This may be due to the age difference of the respondents in the studies, the time gap between menopause and cognitive test, or the difference in measuring menopausal stage(35). Obesity-induced caloric excess is a factor for low-grade inflammation, oxidative stress, and metabolic dysregulation which negatively impacts the brain(36). Many evidences show the relationship between adiposity and cognitive performance. In our study, there was no association between BMI and MMSE cognitive score which is against other studies conducted in China and the US(26,37). Insensitivity of BMI in measuring adiposity and difference in the method of assessing cognitive function might be the reason for the discrepancy.
Anemia is a significant factor in cognitive performance of adults, it can cause symptoms of irritability, fatigue, and poor concentration(38).In the current study, hemoglobin level was significantly associated with cognitive scores which is in agreement with previous studies(39,40)