Adding Letrozole to GH and GnRHa Increase Height in Girls with Short Stature: a hospital record-based retrospective study

Abstract Background There have been rare data in Letrozole for height promotion in girls. This study aims to clarify the efficacy and safety of combination therapy with human recombinant growth hormone (rhGH), GnRHa and letrozole in improving the height of girls with short stature and advanced bone age. Methods This is a retrospective record-based study. Follow-up was conducted on girls with short stature who received rhGH, GnRHa and letrozole treatment at outpatient clinics in our hospital. Total of 29 subjects were included in this report. The control group includes 29 girls with short stature who received rhGH/GnRHa therapy. Results The predicted adult height before treatment (PAH1) was 155.38 ± 3.85 cm, and the PAH after treatment (PAH2) was 161.32 ± 3.72cm (t = 10.375, p < 0.001). The ΔPAH (the increment of predicted adult height) in the treatment group is 4 cm higher than that of the control group (5.85 ± 3.11cm VS. 1.82 ± 1.50cm, Z=-5.506, P < 0.001).There was a significant difference in the height SDS of BA before and after treatment (-1.30 ± 0.70 VS -0.008 ± 0.662, Z=-4.703, P < 0.001).And there was a significant difference in the height SDS of CA(0.015 ± 0.95 VS 0.276 ± 0.88, Z=-2.930, P = 0.003).There was a increasing BMI during therapy (from 19.34 ± 3.33 kg/m2 to 20.43 ± 4.12 kg/m2, Z = 2.065, P = 0.039).The height gain was 8.71 ± 4.46 cm, and the growth rate was 6.78 ± 3.84cm per year. No remarkable side effects were reported in the treatment group. Conclusions Combined treatment with GH, GnRHa and letrozole can enhance the adult height (AH) and PAH in short stature girls and no significant side effects were reported.