Endocrine Abstracts

Recombinant growth hormone (GH) administration uses several different injection devices. Despite offering free patient choice at GH therapy start, ~20% of our patients subsequently change GH device.

Objective: To investigate reasons for GH device change, and evaluate the effect on adherence, height velocity standard deviation (HVSDS), and insulin-like growth factor-1 (IGF1).

Method: Retrospective study of extracted growth data and laboratory results of patients under our unit who changed GH device between January 2001 and January 2011.

Results: One hundred and nine patients (60 female) had a change in GH device (Table 1).

Adherence data for 12 months before and after device change (based on ampoule counting) was available in 30 patients. 9 had 100% adherence before and after device change, 7 had an increase, and 14 had a decrease. IGF1 data was available for 41 patients 12 months before and after GH device change: 29 (71%) had an increase whilst 12 had a decrease. Fifty-four patients had full HVSDS data: 29 (54%) showed an increase, 24 a decrease and 1 no change in the 12 months following changeover. 22 patients had both IGF1 and HVSDS data available: of the 12 with an HVSDS increase, 9 (75%) had an increase and 3 had a decrease in IGF1. Of the 10 with decreased HVSDS, 5 (50%) had an increase, and 5 a decrease in IGF1.

Conclusions: Patients change GH device for a variety of reasons. GH adherence following changeover is variably altered, as are biological responses (HVSDS and IGF1).