Chemo Brain – pro
Post-chemotherapy cognitive impairment (PCCI) (also known as chemotherapy-induced cognitive dysfunction or impairment, chemo brain, or chemo fog) describes the cognitive impairment that can result from chemotherapy treatment. It has been best defined in breast cancer survivors. Approximately 2030% of people who undergo chemotherapy experience some level of post-chemotherapy cognitive impairment. It may become noticeable 2 years after chemotherapy, and is progressive. The symptoms of this condition overlap with depression, anxiety disorders, bipolar illness and other psychiatric conditions. Menopause, the biological impact of a surgical procedure with anesthesia, medications prescribed in addition to the chemotherapy, genetic predisposition, hormone therapy, emotional states (including anxiety, depression and fatigue), comorbid conditions and paraneoplastic syndrome may all co-occur and act as confounding factors in the study or experience of PCCI.
In general, the extent of the impairment can be specifically evaluated with neuropsychological testing and then a neurologist can design a return to work plan. Hypothesized treatment options include the use of antioxidants, cognitive behavior therapy, erythropoietin and stimulant drugs such as methylphenidate, though as the mechanism of PCCI is not well understood the potential treatment options are equally theoretical.None of these are unequivocally proven.
Modafinil, approved for narcolepsy, has been used off-label in trials with people with symptoms of PCCI. Modafinil is a wakefulness-promoting agent that can improve alertness and concentration, and studies have shown it to be effective at least among women treated for breast cancer.
While estrogen hormone supplementation may reverse the symptoms of PCCI in women treated for breast cancer, this carries health risks, including possibly promoting the proliferation of estrogen-responsive breast cancer cells.
The closest we have in evidence to support amphetamines/ stimulants is two studies with methylphenidate, but they are not conclusive. Mar Fan et al. conducted a double-blind, placebo-controlled trial of d-methylphenidate (dMPH) in women with breast cancer receiving adjuvant chemotherapy. There were no significant differences between the dMPH and control groups
with respect to either of the cognitive measures at any of the time points; however, the results may have been confounded by a trend that showed more cognitive impairment at baseline in placebo-receiving patients than those receiving dMPH. Unfortunately, because of poor accrual, the study closed early;
as a result, conclusions from these results must be regarded as tentative. Lower et al. also found little benefit of dMPH on cognition in patients with sustained cancer-related fatigue. In this study, patients had completed four cycles of chemotherapy 25 months previously (on average) and had received dMPH for 8 weeks. Neither of these studies was sufficiently powered to detect a difference, and it therefore remains unclear what effect continuing MPH treatment beyond chemotherapy completion would have on late cognitive outcomes.
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An Overview of Chemotherapy-Related Cognitive Dysfunction, or ‘Chemobrain’
Review Article | September 15, 2014 | Oncology Journal, Breast Cancer, Palliative and Supportive Care
Modafinil Relieves Cognitive Chemotherapy Side Effects Psychiatric News, Stephanie Whyche, August 3, 2007 Volume 42 Number 15, page 31
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