The Limit Does Not Exist

How Data Became My Tool For Understanding Chronic Illness

I stare at the graph on the computer screen in my lap, a series of spiky blue data points with a curvy line snaking through them. A sine wave. But maybe, I think, the single point at the end of the line I added this morning, a seven, has changed something. The angle looks a little steeper. Maybe the trendline has a new trajectory, maybe this time it is headed down for good. Maybe. 

I go through each of my charts: Fatigue, activity, cognitive symptoms, pain, migraine symptoms, anxiety, depression. They all look the same. A slight wavering up and down every couple of months, ending up back where they were a year ago when I started keeping the data. I check my totals. Still around 7 for fatigue, 3 for activity, 5 for anxiety, 4 for depression. I check my distribution. Still a bell curve. I check my correlation matrix. Activity and depression are still perversely correlated with fatigue, the catch-22 I have been locked in since I got sick a year ago. If I do any physical activity, my fatigue gets worse. If I don’t do any activity, my depression suffers. I scroll through the raw data, notes on my daily activities, different treatments I have tried. I check the means, medians, modes. I try to predict what will come next. Eventually, I minimize the window and get up to take my meds. 

When people ask me how I’m doing, I show them the graph. When I am feeling hopeless, I look at the graph. When I am hopeful, graph. Bored, graph. Inspired, graph. It is an obsession. It is a witness, a memory, a concrete record of the inherently vague experience of chronic illness. It is simultaneously scientific and subjective. My scale goes from 1 to 10, each number carrying an entirely different experience of life. At an 8, I can’t get out of bed. At a 7, I can sit up. At a 6, I can leave the house for short periods. At a 3, I could go for a bike ride. Since I started keeping the data, I have never been at a three. 

People tell me I should submit my data to a researcher, that this could be the key to the next great discovery in Long Covid treatment. My system is an improvement on pointing at a smiley face on a chart at the doctor’s office, but the treatments I record are laughter, sunshine, spending time in the water. When I show my data to my doctors, they don’t spare it a second glance.

The Fatigue Log, my official name for my data collection system, is something I started in July of 2023 at the recommendation of my aunt. She had used her own data collection to help her get on disability when she was at her sickest with ME/CFS. I took the idea and made it my own. I used a Google Form to populate a spreadsheet, began to add in new measurements day by day. Every couple of weeks, I would think of a new statistical analysis I might try. I taught myself new functions and commands, learning the language of Google Sheets in bite-size chunks. 

Now, the Log includes thousands of data points and dozens of graphs and charts. Every day, I open up the email I sent to myself with the Google Form and fill it out. The email says “I love you! How was your day?” a note I wrote to myself a year ago that I still see each morning.  

This is how my Fatigue Log looked when I sat down to write this post.

The Log is both a way of distancing myself from the experience of chronic illness and of deriving meaning from it. When fatigue is just a number on a line, it is not an oppressive force pushing me into my mattress like a panini press. When depression is just an average over time, it is not a looming void threatening to pull me in. When migraines are a binary, they are not hours of searing, head-splitting torment.

And, at the same time, it does mean something. The days when I can’t get out of bed are tallied, accounted for, not lost. The passing of time is visible to me, flowing across an axis like a banner announcing the way things change. Each day, I can look back and say, “Oh, yes. That is what it was like.” I track what I am grateful for, what I have done to care for myself. I remember that I am loved, that my daily existence matters. If somebody wanted to understand my experience, the data could at least give them a sense of who I am and how I live. 

My obsession with the charts can’t be entirely healthy, as is the case with any such fixation. I am caught in the classic dialectic of accepting where I am and hoping for things to improve. I think the charts can help with this process and hinder it. I can become caught up in the trends, convinced things will suddenly, magically resolve, trying to manipulate the data to prove it, or I can use the data to see the bigger picture and learn from it. 

Despite my conflicted feelings, I recommend keeping a data log for anyone struggling with a chronic illness. It is a useful document for a doctor or a disability lawyer, despite what I have said to the contrary. It is not very hard to set up, and it can be a real source of comfort when symptoms are bad, especially cognitive symptoms like memory, which can make it impossible to remember when things got worse or if they were ever even better. It can be a reminder that the flare-ups will pass and that the good times are also impermanent, so it is best not to hold too tightly to them and make the most of where you are right now. It can help with pacing, recognizing patterns, creating coping strategies, and managing symptoms when possible. 

There are lots of ways to keep your data these days. There are apps and wearables, many of which have been made specifically with chronic illness in mind. I have not tried these, and cannot attest to their efficacy, but I imagine they serve similar purposes, especially if you do not enjoy fiddling with spreadsheets. I like my way because it gives me more agency and creativity, but it is certainly not the only option. 

Last night, at 1 am, I was scrolling through my phone and saw a video of someone doing something I love: skiing. They were poised at the top of an unreasonably steep cliff in a puffy red jacket. Watching the video, I was transported to the slope. I felt the tension in my quads and the lateral muscles of my legs as I tried to maintain stability and control, the beating of my heart, muffled in the layers of hats and scarves. I was suddenly overcome by an unexpected grief. There may never be a day when I can do something like that again, I thought. And if there is, it is so deeply out of reach from where I am now. 

I shut off the video and opened my spreadsheet. I looked at the sine wave, the steady up and down of my own slope. I looked at the totals, the correlations, the distribution, the raw data. This is where I am, I thought. This is my life. Sad, but somehow comforting. True.

Our next post will be about how you can set up your own symptom log, with tools and examples.

In case anyone is curious, this is the scale I use to track my fatigue. You’ll find that this chart is similar to the one Mariana shared last week. Fun fact: we came up with them completely separately. More charts to come in our next post.

1. Full energy all day, can do very heavy exercise without PEM

2. Very energetic, can do heavy exercise without PEM

3. Energetic, PEM after heavy exercise, can do moderate exercise w/out discomfort

4. Mildly energetic, PEM after moderate exercise, can do light exercise w/out discomfort

5. Mildly fatigued, PEM after light exercise, can do activities out of house w/out discomfort

6. Fatigued, going out causes PEM, can stand up for periods of time w/out discomfort

7. Very fatigued, standing up causes PEM, can sit up for moderate periods of time without discomfort

8. Very fatigued, sitting up causes PEM, can lie down without too much discomfort

9. In pain from fatigue even while lying in bed

10. In pain from fatigue, can only get out of bed to use bathroom when absolutely necessary

    

    Bonus: This is my most fun graph. I love the colors. This is a snapshot from August.