Abdominal Fat Distribution And Bone Metabolism In Patients With Primary Aldosteronism

Background and ObjectiveCardiovascular complications in patients with primary aldosteronism?PA?,including arrhythmia,myocardial infarction,left ventricular hypertrophy and stroke,were significantly increased,and the incidence of cardiovascular events was higher than that in patients with essential hypertension?EH?,independent of blood pressure level.Fat distribution,especially visceral adipose tissue,is a key risk factor for the occurrence and development of cardiovascular diseases.What about abdominal fat distribution in PA patients?Is there a relationship between cardiovascular risk and abdominal fat distribution in PA patients?In addition to cardiovascular and metabolic changes,recent studies have shown that aldosterone excess may also affect mineral balance,but there are few domestic studies on bone metabolism in primary aldosteronism.Therefore,this research compared the abdominal fat area,bone density and related bone metabolism indexes in PA and EH patients matched by age,gender and BMI,and analyzed the correlation between abdominal fat area and indexes such as bone density,glycolipid metabolism and insulin resistance.Object and Method45 PA and 55 EH patients were collected from in-hospital patients who were hospitalized in the First Affiliated Hospital of Zhengzhou University because of suspicion of secondary hypertension from September 2016 to February 2019.All patients were accepted quantitative computed tomography to measure bone mineral density,total abdominal fat area?TFA?,visceral fat area?VFA?and subcutaneous fat area?SFA?at the level of L2/L3 when accepted adrenal CT.Visceral obesity was defined as VFA greater than 130cm².The percentage of visceral fat area in total abdominal fat area?V%=VFA/TFA?,the ratio of visceral fat area to subcutaneous fat area?V/S=VFA/SFA?and the percentage of visceral obesity were calculated.At the same time,bone metabolic indexes such as serum calcium,serum phosphorus,parathyroid hormone?PTH?,25-?OH?V_D3 and alkaline phosphatase?ALP?were collected from all subjects.In addition,15 cases of PA and 27 patients with EH were accepted oral glucose tolerance test and insulin releasing test,calculating insulin resistance index:HOMA-IR=fasting blood glucose?FBG?*fasting insulin?FINS?/22.5 in the steady state model?HOMA?,quantitative insulin sensitivity check index:QUICKI=1/?LogFBG+LogFINS?and insulin area under curve INS_AUC=1/4(FINS+2*INS₃₀+3*INS₆₀+4*INS₁₂₀+2*INS₁₈₀).ResultsTFA and VFA in EH group were higher than those in PA group matched by age,gender and BMI?all P<0.01?,and the differences in SFA,V%,V/S and the percentage of visceral obesity were not statistically significant.No statistically significant differences in FBG,PBG,TG,TC,LDL,HDL,the incidence of impaired glucose regulation and diabetes,FINS,INS_AUC,HOMA-IR and QUICKI were observed between the two groups.There were no statistically significant differences in lumbar average BMD,serum calcium,serum phosphorus,PTH,25-?OH?V_D3 and ALP between the two groups.In PA group,TFA,VFA and SFA were positively correlated with HOMA-IR and FINS?P<0.05 or P<0.01?,TFA and VFA negatively correlated with QUICKI?P<0.05?,TFA positively correlated with TG and LDL?P<0.05?,and SFA positively correlated with TG?P<0.05?.In EH group,TFA and VFA were positively correlated with HOMA-IR,FINS and TG?P<0.05 or P<0.01?,negatively correlated with QUICKI and HDL?P<0.05 or P<0.01?,and VFA was also positively correlated with PBG?P<0.05?.In PA group,lumbar average BMD was negatively correlated with VFA,V%and V/S?r=-0.495,P=0.043;r=-0.592,P=0.012;r=-0.510,P=0.037,respectively?,correlation V%>V/S>VFA,no significant correlation with TFA and SFA?all P>0.05?.In EH group,lumbar average BMD had no correlation with TFA,VFA,SFA,V%and V/S?all P>0.05?.Multiple linear regression model analysis shows in PA group the effect of VFA on lumbar average BMD was statistically significant?P<0.01?,while that of age,BMI,WC,HC,TFA,SFA,V%and V/S was not?P>0.05?.There were no significant correlation between TFA,VFA,SFA,V%,V/S,BMD and supine or standing ALD in both groups?P>0.05?.ConclusionCompared with EH patients matched by age,gender and BMI,TFA and VFA in PA patients were lower,inferring the higher cardiovascular risk was not significantly related to abdominal fat distribution,which may be related to the toxic effect of aldosterone itself.There was a negative correlation between lumbar average BMD and abdominal visceral fat area in PA patients.Further more,abdominal visceral fat area was a negative predictor of lumbar average BMD.