Unmasking Adherence As a Cause of Unexplained Poor Growth Response (PGR) in Adolescents Treated with Growth Hormone (GH)

Program: Abstracts - Orals, Poster Preview Presentations, and Posters
Session: MON 0136-0155-Growth and GH: Diagnostic Issues and Treatment
Clinical
Monday, June 23, 2014: 1:00 PM-3:00 PM
Hall F (McCormick Place West Building)

Poster Board MON-0146
Richard A Noto, MD1 and Nathan Alan Lee2
1New York Medical College, Bellmore, NY, 2New York Medical College
Background:

Diminished adherence to growth hormone replacement (GHR) has been shown to be a cause of poor response to GH treatment. The Easypod System (EPS) has been shown to be an easy reliable tool to track GH adherence. In this study we used the EPS to see if poor response to GHR was caused by poor adherence.

Methods:

To determine if unexplained PGR to GHR was caused by poor adherence we routinely switched patients GHR to the EPS where adherence to dose, date and number of injections can be easily tracked on a daily basis. For this study we reviewed our Saizen roster for patients switched to the ESP to determine adherence to GHR. Multiple parameters for each patient were recorded and tabulated.

Results:

12 patients, 10 males and 2 females, were found with complete data for an analysis. Their ages ranged from 10.3 to 17.0 years with a mean of 15.6+/- 1.9 yrs. and a median of 16.4 yrs. The age that they started GH ranges from 7 to 15 yrs. with a mean of 10.9 +/- 3.3 yrs. and a median of 11.25 yrs. The years on GH treatment range from 1.5 to 9 yrs with a mean of 4.5+/- 2.7 yrs. and a median of 3.75 yrs. Initial height percentile prior to starting GH range from the 1st to the 10th % with a mean percentile of 3.6+/- 2.45 with a median of 3.   Initial height percentile prior to starting EPS ranged from the 1st to 25th %. with a mean percentile of 10.1+/- 8.0 and a median of 10.  Ten patients had MRI studies of which 2 were read as normal 7 with small pituitary glands and 1 with a pituitary cyst.

Only one of the 12 patients acknowledged poor adherence prior to starting the EPS however, it turned out that 10 of the 12 patients were non adherent for the cause of poor growth. At the first visit the EPS demonstrated that 5 patients were not adherent to GHR. After confronting the non-adherent patients about compliance then only one patient remained non-adherent to GHR. 

The growth rate prior to starting EPS ranged from 0 to 6.8 cm/yr with a mean of 2.5+/- 2.4 cm/yr and a median of 2.5cm/yr. The growth rate on Saizen when patients were found adherent including the one continued non-adherent patient demonstrated a growth rate ranging from 0 cm/yr to 11.4 cm/yr. with a mean of 6.3+/- 3.6cm/yr and a median of 6.5cm/yr. This growth rate was significantly greater than the pre-Saizen value P<0.00.  The growth rates prior to becoming adherent for the four non adherent patients who eventually became adherent on Saizen ranged from 2.4 cm/yr to 4.4 cm/yr with a mean of 3.4+/-0.7 cm/yr and a median of 3.3 cm/yr with these growth rates not significantly greater from their pre-Saizen values P=0.29.  The one patient who was non adherent throughout the study period, as well as two poorly growing adherent patients discontinued GH.  GH and IGF-1 was not helpful in determining adherence.

Conclusions:

Adolescents with an unexplained poor growth response to GH treatment show a low rate of adherence to explain their poor growth.

Disclosure: RAN: Consultant, EMD Serono. Nothing to Disclose: NAL

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