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Managing Fatigue With C3G

Pacing yourself, listening to your body and accepting help are key to living well with this rare kidney disease

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One of the most challenging things about living with complement 3 glomerulopathy (C3G) is the overwhelming fatigue it can cause.

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We’re not talking about a little tiredness here and there. We’re talking about exhaustion that changes the way you live your life.

While there’s no way to eliminate C3G fatigue completely, there are things you can do to better manage your energy.

Nephrologist Corey Cavanaugh, MD, explains the causes of C3G fatigue and shares strategies to help you make the most of each day.

Why does C3G cause fatigue?

C3G causes fatigue both directly and indirectly.

“It’s partially the disease itself, but it’s also a consequence of living with a rare chronic illness,” Dr. Cavanaugh says.

Direct causes of fatigue

Living with C3G means ongoing immune system activity (like inflammation) damages your kidneys over time. That can leave you feeling worn down, especially as your kidney function declines.

For some people, C3G eventually causes kidney failure, which makes fatigue even worse.

Indirect causes of fatigue

C3G (and some C3G treatments) can contribute to other health problems that drain your energy, including:

  • Anemia: Chronic kidney disease (CKD) can cause energy-sapping anemia by reducing levels of erythropoietin, a hormone that stimulates red blood cell production.
  • Nutritional issues: Some people with C3G develop deficiencies in protein, iron, folate and other essential nutrients. It happens for many reasons, from dietary restrictions and nausea to proteinuria — when you lose protein in your pee.
  • Fluid management issues: When your kidneys aren’t working well, fluid and waste build up, causing swelling, a heavy, bloated feeling and shortness of breath. But if you don’t drink enough or overdo it on water pills, you can end up dehydrated. Both can leave you feeling exhausted.
  • Gout: Uric acid is one of the waste products that can build up when kidney function declines. The excess may cause crystals to form in your joints — a condition called gout. Not everyone with C3G develops gout, but those who do experience severe joint pain that can make fatigue worse.
  • Recurrent infections: Some C3G treatments suppress your immune system, which can raise your risk of getting sick. And fighting off those infections can leave you tired.

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The physical effects aren’t the only reason fatigue is so common in C3G. Dr. Cavanaugh also points to the cumulative impact of living with an ultra-rare disease.

“You’re in and out of the doctor’s office so much for appointments, treatments, lab work, etc., that it takes on a life of its own,” he recognizes. “The chronic stress can be extremely draining.”

Let’s not forget, you have a life outside of C3G. And it may also include health conditions — like depression, diabetes and sleep apnea, for example — that can cause fatigue in their own right.

How it affects your daily life

The physical, mental and emotional effects of C3G fatigue can be devastating. You have to ration your energy to get through every day, which can mean:

  • Having less time for friends, family and activities you enjoy
  • Difficulty keeping up with work, school and other obligations
  • Feelings of frustration, guilt and shame

Many people with chronic illnesses have these experiences. But Dr. Cavanaugh notes that conditions as rare as C3G come with their own challenges.

“It can feel like you’re on an island. It’s really, really isolating,” he shares. “And most of the symptoms are invisible, so the people around you may not understand or appreciate what you’re going through.”

Does fatigue mean the disease is progressing?

C3G fatigue can be a source of stress, especially if it flares up unexpectedly. But it doesn’t always mean that your condition is getting worse. Exhaustion can spike even when your lab results are stable.

So, why is it happening?

It can be hard to nail down a cause, Dr. Cavanaugh says. It could be related to C3G progression, but it could just as easily be a result of other fatigue drivers, like:

  • Blood pressure
  • Treatment side effects
  • Sleep problems
  • Stress

There’s still a lot we don’t know about C3G. And the tools providers use to measure what’s happening in your body are imperfect, at best.

“It’s common to look back and realize that your inflammation levels were really high, even though your labs hadn’t changed very much,” Dr. Cavanaugh illustrates.

That’s why it’s important to trust yourself. Tell your healthcare team how you’re feeling, even if your test results look fine.

“There’s only so much we can tell you from your labs and a 20-minute appointment every few months,” he continues. “We’re depending on you to tell us how you feel.”

Strategies to manage C3G fatigue

Trusting yourself isn’t always easy, but Dr. Cavanaugh says it’s the single best thing you can do to protect your energy when you’re living with C3G.

“Listen to your body. You’ve lived in it. You know it,” he advises.

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It’s also important to work with a provider you trust.

“In C3G, it’s your nephrologist’s job to monitor your labs,” he adds. They’ll let you know when you’re doing OK and when you may need to be more cautious.”

Dr. Cavanaugh also recommends that you:

  • Talk to your provider about exercise. Gentle exercise may help boost your energy and is a great way to support your overall health. Just check in with your nephrologist before starting a workout program. “If your kidney function looks good, then go for it,” Dr. Cavanaugh encourages.
  • Protect your rest. Treat relaxation like it’s mandatory ... because it is. Eat at your desk and use your lunch break to nap. Have a standing appointment with your couch and a good book one night a week. After infusions, build in an hour to lie down.
  • Have realistic expectations. You’ll have days when you’re too wiped out to stick to a rigid schedule, keep up with your responsibilities or even have fun. Knowing that ahead of time — and making back-up plans — can make cancelling a little easier.
  • Plan your recovery time. If you’re set on going to that party on Saturday night, keep your calendar clear on Sunday so you can recharge.
  • Ask for help (and accept it). Small gestures from family, friends and coworkers can make a big difference in your day-to-day life, but only if you let them help.
  • Spend your energy on the things that matter most to you. For example, go to your kid’s basketball game and order takeout afterward. That way, you don’t have to find the energy and motivation to cook and do dishes after a night out.

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Bottom line? “You’ve got to know your limits,” Dr. Cavanaugh stresses. “Everybody’s a little different. So, do what works for you, not what you think you should do.”

When to talk to your doctor

Fatigue is an everyday occurrence when you’re living with C3G. But it’s still a symptom. And you still need to take it seriously. Especially if it’s:

  • New
  • Worse
  • Not improving with treatment

“Even if the exhaustion isn’t out of the ordinary for you, if it’s ongoing and you feel like it shouldn’t be, tell your nephrologist,” Dr. Cavanaugh advises. “That’s a signal to us to check your blood work, urine studies and blood pressure, to make sure all is well."

C3G fatigue is real

C3G fatigue isn’t something you can see or measure. But it’s very real.

“People sometimes wonder: Is this fatigue a symptom of my disease? Or is this just me and my brain?” Dr. Cavanaugh shares. “It’s not just you. It’s a side effect of your condition. So, try to give yourself a break.”

Dealing with C3G fatigue isn’t easy or fun. But understanding your symptoms is an important first step. There are no quick fixes, but by working with your provider and loved ones, you can find strategies that make daily life more manageable.

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