March 19, 2017 by Leah
Once we finally, belatedly, established that I have CKD, my nephrologist and I had a few other things to discuss. I’ve asked him at every appointment if there’s not something – anything – I can be doing to help myself, and he keeps saying no, or mentioning ACE inhibitors, diuretics, and any number of other drugs that are incompatible with breastfeeding. So I tell him said drugs are incompatible with breastfeeding, and then he says he doesn’t want to mess with my lifestyle and how long am I planning to breastfeed, anyway? To which I answer that my hope, with this last baby, was to go as long as she wanted to. But obviously that’s not going to happen, since my doctor blanched when I told him I nursed the other two 20 and 16 months, respectively.
He also really likes to tell me about all the comorbidities involved with CKD. Heart disease and stroke are the things that kill most kidney patients (which is fine, since I was kind of expecting heart disease would be my downfall as it is the number one killer of women in America, and because I have some genetic predisposition).
One of the intricate and scary details of kidney failure is that your kidneys stop converting vitamin D (from food and the sun on your skin) into its active form that can be used by your body. Vitamin D is necessary for the transfer of calcium from food into your body’s cells. So, when the kidneys stop converting Vitamin D, blood levels of calcium fall. Your parathyroid (four small glands nestled in next to your thyroid) is responsible for producing parathyroid hormone (PTH), which regulates calcium levels in your body. When the calcium levels in your blood fall, the parathyroid starts pumping out more PTH, which pulls calcium from your bones to normalize the calcium level in your body. Higher levels of PTH also interfere with your body’s ability to dispose of potassium on a cellular level, while at the same time, failing kidneys aren’t able to dispose of excess potassium or phosphorous through normal channels, so levels of potassium and phosphorus rise in your body. Calcium leaching out of your bones can cause bone issues like osteoporosis and infection. Excess potassium leads to a condition called hyperkalemia, which interferes with muscle performance in ways that can include heart attacks. Excess calcium, potassium, and phosphorus floating around in your body can also – over time – cause buildup and blockages in your blood vessels and heart valves.
To make matters worse, I also have high cholesterol. This is normal during the latter part of pregnancy and breastfeeding, to the point where many doctors won’t even check cholesterol in pregnant or breastfeeding moms since it’s not considered accurate until breastfeeding is completed; however, breastfeeding moms don’t make up a large percentage of a nephrologist’s normal patient population, so my nephrologist enjoys making dire predictions about all the “stuff” (cholesterol, potassium, phosphorus) “floating around in there” and then I leave feeling like a ticking time bomb.
That said, breastfeeding has a measurable impact on a mother’s cardiovascular health. A 2010 article in Scientific American states that women “who had breastfed for more than 12 months were about 10 percent less likely to develop cardiovascular disease compared with women who had not breastfed.”
My kidney disease has progressed enough that my parathyroid hormone levels are too high and my potassium levels are rising. I’m taking a medication called Calcitriol that replaces the active version of Vitamin D that my kidneys should be making and that is helping my body process calcium and therefore keeping my parathyroid in check. There’s also a new (just approved in 2010, apparently) drug called Sensipar that mimics the action of calcium circulating in the blood and tricks the parathyroid into toning down the hormonal output that my nephrologist would like to see me get on, but it’s so new that there’s no data on using it while breastfeeding and therefore we’re holding off.
So. Do I keep breastfeeding? Do I stop so I can keep the cholesterol from building up in my arteries, get on Sensipar and ACE inhibitors, and hope that the kidneys I was born with keep limping along, or do I keep nursing in the hope that the heart disease risk factors from CKD and breastfeeding will cancel each other out? I also have a tendency to get depressed when I wean my babies, and I’m already on Zoloft (for reasons including: everything that has happened since mid-August). I don’t know. Right now I’m exclusively nursing and also pumping three times a day to try to build up enough of a freezer stash to get M through to her first birthday no matter what I decide.