Study On The Correlation Between Pituitary Size And Growth Hormone Peaks In Patients With Short Stature

Objective:To analyze the influencing factors of pituitary size and the correlation between pituitary size and growth hormone(GH)peak in patients with short stature.Methods:This study included 440 patients with complete pituitary measurement data in the Shandong growth and Development Disease Cohort follow-up study Database from April 2013 to January 2018,including 377 patients with short stature and 63 shorter patients.All patients were divided into complete growth hormone deficiency(cGHD)group,partial growth hormone deficiency(pGHD)group and idiopathic short stature(ISS)group according to the diagnostic criteria of short stature and the peak value of GH.The general data of the patients were collected,such as age,sex,birth history,growth and development history,past medical history and so on.The clinical examination data such as height,weight,development and so on were collected.According to height and weight to calculate the body mass index and its standard deviation score(SDS).The growth hormone peak in two growth hormone stimulation tests and the concentration of insulin-like growth factor-1were collected.Imaging examinations such as pituitary MRI and X-ray films of left hand bone,carpal bone,ulna and radius were collected.The pituitary height(PH),pituitary width(PW)and pituitary length(PL)were measured by special personnel,and the pituitary volume(PV)was calculated according to the formula,and the bone age was evaluated according to Greulich-Pyle atlas.Results:The height of shorter patients was higher than that of short stature patients,and the PH,PW and PV of short stature patients were significantly higher than those of shorter patients(P<0.05).Among the patients with short stature,grouped by peak GH,the PH,PW,PL,PV had no significant difference among cGHD,pGHD and ISS patients(P>0.05).Smooth curve fitting showed that PV was positively correlated with age,and an inflection point was found at 14 years old.After adjusting the confounding factors,in a group younger than 14 years old,PV increased by 5.85 mm~3 for each 1 year increase in age(P<0.01).Grouped by Tanner stage,the PH,PW,PL,PV in the puberty group were significantly larger than those in the prepuberty group(P<0.05).The peak GH and IGF-1 in the puberty group were higher than those in the prepuberty group(P<0.001).Grouped by gender,the differences in PH,PW,PL,PV of patients with short stature between different gender groups were not statistically significant(P>0.05).Grouped by BMISDS quartiles,the PH,PW,PL,PV were not significantly different among different BMISDS groups(P>0.05).The correlation between pituitary size and GH peak was further analyzed by linear regression.After adjusting the related factors,in the puberty pGHD group,the GH peak increased significantly with the increase of PW,PL and PV,the difference was statistically significant(P<0.05).The GH peak increased by 1.12ng/ml for every1mm increase in PW(P<0.005);for every 1mm increase in PL,the peak of GH increases by 0.38ng/ml(P<0.05),and for every 1mm~3 of PV,the peak of GH increases by 0.02ng/ml(P<0.005).No correlation was found between PV and GH peak in the three groups of prepuberty patients and the groups of cGHD and ISS in puberty.Conclusions:This study shows that the pituitary of short stature patients is smaller than that of shorter patients.In patients with short stature,the size of the pituitary gland is affected by age and puberty.At less than 14 years old,pituitary volume is positively correlated with age.No differences in pituitary size among patients with cGHD,pGHD,and ISS,nor gender differences,body mass index differences.This study only found that the larger the pituitary volume,the higher the growth hormone peak in some patients with partial growth hormone deficiency after puberty.