Effect Of Dietary Selenium Supplementation On Lower Urinary Tract Symptomes In Patients With Benign Prostatic Hyperplasia

ObjectiveThis study aimed to compare the differences of serum selenium and hair selenium levels between patients with benign prostatic hyperplasia(BPH)and non-BPH healthy subjects,and to explore the effect of dietary selenium supplementation on lower urinary tract symptoms in patients with BPH.Through this research,we wish to provide scientific reference for discovering nutritional therapies besides surgery and medication method and for dietary guidance in BPH patients.MethodsThis study was composed of two parts.Part I:A convenient sampling method was applied to recruit 50 BPH patients and 50 non-BPH healthy men according to the inclusion criteria.Apart from the general demographic data and clinical data,blood and hair samples were collected for serum selenium and hair selenium level testing.Data were compared between BPH and non-BPH subjects.Part II:This study was a double-blind randomized controlled trial.Through convenient sampling method,a final of 28 patients who met the inclusion criteria were in the experimental group and 29 in the control group.The experimental group received daily dietary selenium supplement(selenium-enriched corn flour,40g)containing selenium 200μg.The control group received daily placebo(ordinary corn flour,40g)containing selenium about 0.9μg.The supplement lasted for 12 weeks.Besides,oral health education were provided for both groups of patients in the beginning of the intervention.The parameters of serum selenium levels,hair selenium levels,International Prostate Symptom Score(IPSS),Revised Version of Quality-of-life Scale for Benign Prostatic Hyperplasia Patient(Revised BPHQLS),Pittsburgh Sleep Quality Index(PSQI)and related biochemical indicators were compared in two groups before and after 12 weeks of intervention.The normal distributed data were expressed as mean ± standard deviation(x±s),the non-normal distributed were expressed by median(interquartile range)[M(P25,P75)],and the count data were expressed as frequency.The results were analyzed by t-test,variance analysis,chi-square test,rank sum test,fisher exact probability method and correlation analysis.Results1.The serum selenium level in the case group was lower than the normal reference range,and the hair selenium was within the normal reference range.The serum selenium and hair selenium levels in the control group were within the normal reference range.The serum selenium and hair selenium levels of the former were significantly lower than those of the latter(P<0.05),and the number of serum selenium deficiency was significantly higher than that of the latter.The comparison of the selenium levels in BPH patients based on different disease characteristics showed that the serum selenium and hair selenium levels in patients of BPH were not significantly different among patients of different durations of disease,degrees of hyperplasia and symptom classifications.2.There was no statistically significant difference among the experimental group and the control group in baseline data(P>0.05).3.The results from intra-group comparison of each index in the two groups before and after intervention included:①Selenium level:the serum selenium and hair selenium levels after supplement were higher than before in the experimental group(P<0.001),whereas there was no significant change in the control group(P>0.05).②Lower urinary tract symptoms:the IPSS score decreased slightly after intervention in the experimental group without significance(P>0.05),and no change in the control group(P>0.05).The IPSS score of the two groups were significantly lower after intervention than before in the patients who had significant change(P<0.001),while the IPSS score of remained unchanged(experimental group)or increased(control group)in the patients with non-significant change.③Quality of life:there was no significant change in the score after supplement in both groups(P>0.05).④Sleep:there was no significant change in the score of PSQI after supplement in both groups(P>0.05).⑤Biochemical indicators:after supplement,the biochemical indexes such as AST,TP,ALB,CHOL,HDL and LDL in the experimental group were significantly lower than before(P<0.05),and the biochemical indexes such as TP,ALB,ALP,Cre,CHOL,HDL and LDL in the control group were significantly lower than before(P<0.05).4.The results from between-group comparison of each index after supplement in the two groups included:①Selenium level:the serum selenium and hair selenium levels in the experimental group were significantly higher than those in the control group(P<0.001).②Lower urinary tract symptoms:there was no significant difference in IPSS score between the two groups(P>0.05),and the comparison of the difference of each item score between the two groups failed to show statistically significant(P>0.05).③Quality of life:there was no statistical difference in each dimension score of QOL between the two groups(P>0.05)④Sleep:there was no statistical difference in each dimension score of PSQI between the two groups(P>0.05).5.The relationship between the baseline IPSS score and the intervention effect:there was a significant negative correlation between the baseline IPSS score and the difference of IPSS score before and after the intervention(IPSSafter-IPSSbefore).ConclusionThis study found that serum selenium level in BPH patients was lower than normal level,hair selenium level was in normal range,serum selenium and hair selenium level was significantly lower than that of healthy men of the same age.After 12 weeks of dietary selenium supplementation,the levels of serum selenium and hair selenium in BPH patients were significantly increased.But there were no significant changes observed in lower urinary tract symptoms,quality of life and quality of sleep.In addition,there was a positive correlation between the improvement of lower urinary tract symptoms and the severity of baseline symptoms in patients with bph after intervention.