Cancer patients have long joked and complained about the mental fogginess that can descend during and after treatment.
Now scientists think the phenomenon known as 'chemo brain' really does exist after they conducted a large study review.
Doctors already knew that radiation treatment of the brain could cause thinking and memory problems. However, they have only recently considered whether chemotherapy drugs could cause problems with concentration, forgetfulness and problems with multi-tasking.
Chemotherapy is a drug or combination of drugs that kill cancer cells. A review suggests it can cause cognitive impairment
In the latest study from the Moffitt Cancer Center in Florida, a team analysed previous studies looking at the effect of chemotherapy on breast cancer patients.
They found that the women on average had mild impairments in verbal abilities (such as difficulty choosing words) and visuospatial abilities (such as getting lost more easily).
The study noted that the results varied across survivors, with some reporting no problems while others had more severe deficits.
Although this is an active area of research, an overall analysis of the studies had not been performed since 2006.
Study co-author Paul Jacobsen, said: 'Our analysis indicated that patients previously treated with chemotherapy performed significantly worse on tests of verbal ability than individuals without cancer.
'In addition, patients treated with chemotherapy performed significantly worse on tests of visuospatial ability than patients who had not had chemotherapy.'
Colleague Dr Heather Jim, added: 'Breast cancer patients treated with chemotherapy who have subsequent cognitive deficits should be referred to a neuropsychologist for evaluation and management of the deficits.
'Management usually involves developing an awareness of the situations in which their cognitive difficulties are likely to arise so that they can come up with strategies to compensate. Research shows that such strategies can make a big difference in daily life when cognitive difficulties do arise.'
Other factors that may play a part include anxiety, old age and depression.
The study was published in a recent issue of the Journal of Clinical Oncology.
Read more: http://www.dailymail.co.uk/health/article-2198712/Chemo-brain-DOES-exist-finds-study-breast-cancer-patients.html#ixzz25cb6FhRi