Country-specific differences in adult growth hormone deficiency diagnosis and treatment rates

Navid Nedjatian; Hollander Bjørnar den; Yacine Amirouche

doi:10.1530/endoabs.70.AEP750

Background: Adult growth hormone deficiency (AGHD) is a rare disease associated with adverse metabolic abnormalities and possibly increased cardiovascular morbidity and mortality. Although basic prevalence data is available, little is known about the rates of diagnosed and treated patients.

Aim: To understand the rates of AGHD diagnosis/treatment and details about patients’ growth hormone (GH) dose, age and treatment duration.

Methods: From 2015–2018, 435 endocrinologists across US, Germany, Switzerland, UK, France and Japan completed a survey providing details about the number of AGHD patients under their care, number of patients treated, GH dose, age and treatment duration. Percentages of undiagnosed patients were estimated based on respondents’ projections of undiagnosed patients and published prevalence literature. Results were stratified by country and AGHD subtype (childhood onset [CO], pituitary adenoma [PA] and traumatic brain injury [TBI] and others [not shown]).

Results: The numbers of diagnosed and GH-treated adult patients across the six countries are shown in Table 1. In the US, Germany, Switzerland and UK, mean GH dose ranged from 0.43–0.78, 0.42–0.48 and 0.40–0.56 mg/day for AGHD-CO, -PA and -TBI, respectively. The opinion of the respondents regarding the gap in diagnosis is summarised in Table 2. Treatment duration, drop-out and resumption rates varied by country and AGHD subtype.

**Table 1**
	US	Germany	Switzerland	UK	France	Japan
AGHD-CO
Patients diagnosed, N	3,325	1,252	142	2,052	560	1,346
Patients treated, N (%)^*	2,333(70.2)	964(77.0)	101(71.1)	1,549(75.4)	438(78.2)	1,070(79.5)
AGHD-PA
Patients diagnosed, N (%)	7,177	2,059	211	5,215	1,658	2,323
Patients treated, N (%)^*	3,352(46.7)	1,128(54.8)	119(56.3)	3,695(70.8)	1,283(77.4)	1,751(75.4)
AGHD-TBI
Patients diagnosed, N (%)	6,324	1,651	123	1,735	553	1,093
Patients treated, N (%)^*	2,229(35.2)	768(46.5)	61(49.6)	1,255(72.3)	428(77.4)	824(75.4)
^*Of diagnosed patients. AGHD-TBI with persistent hypopituitarism.

**Table 2**
	US	Germany	Switzerland	UK	France	Japan
Estimated undiagnosed patients,%

AGHD-CO	17.4	16.1	15.1	34.0	18.6	4.7
AGHD-PA	56.4	53.2	53.7	31.0	21.3	36.0
AGHD-TBI^*	64.3	54.7	55.7	42.0	21.3	35.8
^*AGHD-TBI with persistent hypopituitarism.

Discussion: The analysis suggested substantial differences in diagnosis/treatment rates of AGHD-PA and AGHD-TBI, with lower rates in US, Germany and Switzerland compared with UK, France and Japan. The AGHD-CO diagnosis/treatment rates were relatively high everywhere as expected based on preceding childhood diagnosis. Determining the causative factors behind country-specific differences in GH treatment may help improve care for AGHD patients.

Endocrine Abstracts

AEP750