Fact #4: The symptoms of PWS change over time in individuals with PWS. Babies frequently are tube fed and may have failure to thrive. Symptoms of hyperphagia commonly appear sometime between the ages of 3 and 8 but are variable on onset and intensity.
There are several phases involved in the development of hyperphagia. Phase 0 occurs in utero, with decreased fetal movements and growth restriction compared to unaffected siblings. In phase 1 the infant is hypotonic and not obese, with sub-phase 1a characterized by difficulty feeding with or without Failure to Thrive (ages birth-15 months; median age at completion: 9 months). This phase is followed by sub-phase 1b when the infant grows steadily along a growth curve and weight is increasing at a normal rate (median age of onset: 9 months; age quartiles 5-15 months). Phase 2 is associated with weight gain. In sub-phase 2a the weight increases without a significant change in appetite or caloric intake (median age of onset 2.08 years; age quartiles 20-31 months;), while in sub-phase 2b the weight gain is associated with a concomitant increased interest in food (median age of onset: 4.5 years; quartiles 3-5.25 years). Phase 3 is characterized by hyperphagia, typically accompanied by food-seeking and lack of satiety (median age of onset: 8 years; quartiles 5-13 years).
Excerpt above taken from Nutritional Phases in Prader-Willi Syndrome May 2011 American Journal of Medical Genetics Part A
After birth, it was immediately apparent that Clementine was weak and had a poor sucking reflex. She was also extremely sleepy and couldn’t be kept awake long enough to attempt to breast feed. Clem was placed in the NICU. Genetic testing was ordered when it became clear that something out of the ordinary was happening. Clem was released to come home after a one week NICU stay.
Luckily for us, Clem never required a feeding tube. She had just enough energy to feed from a bottle. But boy what a process! In the beginning, she could only feed for about 10 minutes and usually only consumed about 1 to 1.5 ounce of breast milk at a time. I pumped breast milk for 1 year. Clem never managed to breast feed but at least she was able to drink breast milk from a bottle.
When Clementine was 18 months old, she was diagnosed with T1D (Type 1 Diabetes). Leading up to her diagnosis, she experienced significant weight loss, otherwise known as diabetic wasting. After her diagnosis and once insulin treatment began, she began to develop the weight gain typical of kids in phase 2(a).
This was followed by the appearance of phase 2( b) at age 2.5. It was around this time that Clem began to show an increased interest in food. She started to take any food that was left out and available. You can imagine the short term consequences of this for someone who is diabetic! Luckily Dr. Miller prescribed an experimental medication that seemed to dull the drive to forage. We placed locks on all cabinets and the refrigerator and things became manageable again.
Since then, Clementine has remained in phase 2(b). She is an opportunistic food seeker. If it’s available, she will take it. Often she will take something only to hide it in her room and forget that it’s there. Her foraging, at least at this point, is more of a compulsion than true hyperphagia.
There are times that Clem will not eat all of her food at meals and there are also foods that she doesn’t care for and simply won’t eat. She doesn’t ask for food but is very interested in the meal schedule and can’t tolerate much change to it. She’s keenly aware of her food restrictions and while she accepts them, she does feel the sharp unfairness of it.
Clementine is now 11 years old. I truly believe that if she had not had access to some experimental medications, the best medical care available and a genetic propensity toward a petite frame ( thanks to my husband’s family), she would be in phase 3, full blown hyperphagia. I am so thankful for this delay but I know that it’s just that.. a delay. Within the next few years, Clem will slip into hyperphagia and we don’t know how she will tolerate it. How would anyone tolerate feeling as if they are starving 24 hours a day, 7 days a week?
This is where Running for Research comes in. Research is the only path toward avoiding what is now inevitable. Research is the vehicle to understanding the mechanisms of hyperphagia and the means to mitigate it. Please consider joining our fundraising team or making a donation to our cause