Chemotion

Last week I took a week off from chemotherapy to celebrate Easter and regain strength for the last few weeks of chemotherapy. I noticed that I've been feeling more emotional lately, about the experience of cancer, toward personal relationships, and even in response to television shows and news stories.

Other cancer survivors have warned me that the period after treatment can be harder emotionally than treatment itself. The common belief, I think, is that one has to act strong and determined to tolerate the stress of treatment. After treatment, patients let their guard down and all the repressed feelings resurface. My increased emotion could be anticipation of finishing treatment and greater openness from discussing the experiences in support groups.

But this week as another dose of chemo builds in my system I feel the emotional numbness and detachment returning. I think now that it may in fact be another aspect of chemobrain. Just as memory, concentration, and agility are gummed up by therapeutic poisons, maybe emotion is too.

I have been looking forward to regaining my full intellectual abilities after two long years of chemotherapy. It will be interesting to see how my emotional state could change with recovery too.

Scrambled brain

Chemotherapy continues to wreak havoc with my memory. But the scientist in me has been interested to discover some clues about how memory works.

I've known since my first round of chemotherapy in 2004 that the drugs interfere with my mental function just as much as they produce the usual bodily problems like nausea and diarrhea. On bad days especially I have trouble forming new memories, which is a merciful form of amnesia. But on those days I also have trouble recalling events from good days in the past. That's rather inconvenient since I'm currently on chemo two weeks per month and it's hard to get any work done or keep up with everyday tasks while I have Swiss cheese in my head.

Some of the memories return when I go off of chemo, but many seemed to be lost permanently. However, I have discovered that associated senses can bring back past events. A familiar smell or returning to a particular place can release a flood of related memories. So it's not always a loss of the memory from my brain but a disruption in my ability to access that information at will. I recently learned more about this phenomenon due to the assortment of medications that I take along with cancer treatment.

My Xeloda chemotherapy gives me mild to moderate nausea and I haven't found a good medication to alleviate it. I have medications that work great for severe nausea, but they have side effects like drowsiness, constipation, or unpleasant taste, so I try to avoid them when my nausea is milder. One medication that I sometimes use is Marinol which is synthetic THC, the active chemical in marijuana. It sometimes helps suppress the nausea and give me the munchies so that I can enjoy a good meal. But for me it takes a couple hours to kick in, it doesn't always work, and when it does work it can make me feel a little goofy. Since my main goal is to be able to perform and enjoy my usual activities, most of which are cerebral, I avoid Marinol except on the worst days when I would be debilitated by nausea otherwise.

I thought that maybe the reason I wasn't getting consistent relief from Marinol was that I was taking too low of a dose. The pills are 5 mg and the directions are to take one every 2 to 4 hours for up to 30 mg per day. I had only ever taken a single pill in a day. So on a bad day last week when the first pill didn't have a noticeable effect after two hours I went ahead and took a second one.

Finally my appetite improved and I made myself a nice dinner. But two hours later, when I thought that the first pill should be wearing off, something strange happened. I was playing a video game online and I started having trouble remembering what I was doing. I accidently made a move against my teammate because I forgot he wasn't my opponent.

Then over the next half hour the confusion increased. I kept realizing that I was playing a game as if it were something that I didn't previously know: "Oh yeah, I'm playing Starcraft. I guess I better make a move. Oh yeah, I'm playing Starcraft. I guess I better make a move. Oh yeah, I'm playing Starcraft...."

I had just enough presence of mind to realize that I should probably get off the computer and go lie down on the couch. I think that I won the game, but I can't remember exactly how. For the next few hours I watched movies on TV that I've seen a thousand times before: Saving Private Ryan, Star Wars, etc. But I kept noticing scenes as if I had never seen them. My appetite was better, but I was afraid to eat since I couldn't remember whether I had already eaten and didn't want to get over full.

I started to recall very old memories from my childhood and high school days. I experienced a strange sensation of time — I kept thinking that my present state of watching movies on the couch was also a memory. I couldn't distinguish which memories were closer to the present; they all seemed equally real and relevant to me. It was only intellectually that I could reason that it must be whichever memories in which I was oldest that belonged to the present.

I managed to keep myself planted on the couch for several hours and then go to bed. At least I think I did. My main thoughts at the time were: "If this is how it feels to smoke marijuana then I don't see the attraction" and "Taking two Marinols is something to avoid in the future."

I felt very confused the next day. The newly refreshed memories of my childhood were in my head and I still didn't have an innate sense of what was past and what was present. Ironically, even though I'm going through treatment for cancer, this is actually one of the happier eras in my life. It's disconcerting to feel that I might still be going through the hell of high school and the turbulence of early adulthood.

A week later I am getting a little more convinced that July 2007 is the present. With a few days break from chemo I managed to get my brain back in gear and get some work done. I have also realized that the episode reveals that many memories that I thought were lost due to time and chemotherapy are still stored in there somewhere and await rediscovery.

Chemobrain

One side effect of chemotherapy that I never knew existed until I experienced it myself is chemobrain. I noticed after receiving a few doses that along with feeling physically sick I also felt different mentally. My mind was functioning slower as if the gears in my head were getting gummed up with molasses. The effect would be worse for about a week after each infusion and then gradually improve.

I have experienced chemobrain to varying degrees from all three of the chemotherapy regimens that I've received and from a special chemotherapy dose given during my biggest surgery. The main symptoms are:

• Impaired memory
• Difficulty concentrating
• Reduced intelligence
• Diminished creativity
  
• Lack of ambition
  

During my FOLFOX chemotherapy I felt crappy from infusion on Wednesdays until I started recovering on Sundays. Fridays and Saturdays were the worst -- I would mostly lie on the couch listening to the TV and eating very little. So when I felt a little better on Sunday I liked to get out of the house to see a movie with my girlfriend. But I discovered that I couldn't remember what I saw! I would see the same movies in the video store a few months later and not be sure whether I had seen them already. When my girlfriend reminded me that we had seen them together then I could recall the outing but still not remember much about the plot.

Failing memory is also a problem with relationships. Family and friends will call to check how I'm doing and I won't be able to remember what events we've already discussed or who has called recently. When presented with evidence I will vaguely recall the conversations but I often forget about events without reminders. I've probably done damage to my credit rating by forgetting that I had received bills in the mail and not getting around to paying them until I feel more clear-headed weeks later.

Beyond memory impairment I also suffer from other mental difficulties. My job is very mentally demanding (theoretical chemical engineering) and my personality is intellectual and introverted. But on days when chemobrain is bad I can barely manage to read and understand a newspaper. It's hard to concentrate on a subject or reason beyond a superficial extent. Television has become a good friend for giving me enough stimulation to keep me entertained without demanding much concentration or analysis.

I feel as though I lose twenty IQ points when I'm on a dose of chemotherapy. When I had a big surgery at the National Institutes of Health and was given a massive infusion of 5-fluorouracil I felt like I lost sixty IQ points. I could barely read and felt like an imbecile. Even many television shows were too challenging. The old game show The Price Is Right became the highlight of my days.

I don't know what the biological mechanism of chemobrain is. Maybe the chemotherapy drugs kill some brain cells along with the cancer, digestive, skin, and hair cells. Maybe it's not the drugs themselves but metabolic byproducts, the chemicals released during breakdown of cells, or changes in body chemistry resulting from the chemical load on the kidneys and liver.

Of course the chemotherapy drugs themselves aren't the only thing in my body during treatment. I take the antianxiety drug Ativan to reduce nausea and apprehension on infusion days and other times when I'm not feeling well. I also take the antianxiety/antidepression drug Paxil to manage associative nausea. I've read that anxiety is a big factor in the conversion of short-term memories to long-term storage. That's why people remember stressful events like the Challenger explosion or September 11th so clearly. Researchers have administered antianxiety drugs to prevent post-traumatic stress disorder in victims of war and accidents. I suspect that the antianxiety drugs that I take for nausea likewise interfere with long-term memory. It can be a blessing, since this aspect of chemobrain dims my memories of hospitalization and sick days.

I feel chemobrain most intensely for about a week after each infusion. It gradually fades away over the next couple weeks, and when I get a break from chemotherapy I start to feel really good as my mental abilities return. I often experience bouts of creativity and ambition as if I've been on vacation and just returned to an old problem with fresh eyes.

From talking to other cancer survivors I've learned that chemobrain can be a long-term problem. Many people experience memory impairment for three years after finishing chemotherapy or never recover completely. Being that my job and personality are so dependant on my mental abilities I was frightened that I would lose my intelligence permanently. But during my period of remission I felt at least as smart as I ever was -- maybe even smarter since I've gained wisdom and coping skills from my struggles. So although I still feel hampered by chemobrain I expect that I'll return to my usual self whenever I can get off of chemo.