Analysis On Quality Of Life And Burden Of Sporadic Creutzfeldt-Jakob Disease In China

Prion diseases or transmissible spongiform encephalopathies(TSEs),are characterized by fatal neurodegenerative lesion in human beings and many other animals.For the long incubation period,high lethality and possible infectivity,prion diseases have become a worldwide public health problem.Creutzfeldt-Jakob Disease(CJD)is the main kind of human prion diseases.Sporadic CJD(sCJD)is the most popular disease that accounts for nearly 85%-95%among all subtypes of CJD and can lead to neurological and psychiatric symptoms including dementia,tremble,ataxia,illusion and acousma even akinetic mutism With serious damages to physical health,patients’ ability to work and to take care of themselves decline.The quality of life of patients strikingly reduces as well.Meanwhile,the disease brings burden to patients’ families and society and hinders the development of social economy.In this study,we evaluated the quality of life of patients who suffered from sCJD with EQ-5D instrument.Secondly,we obtained indexes for disability levels and average disability weight(DW)by Delphi method.Finally,we calculated Disability adjusted life year(DALY)and indirect economic burden to represent the disease burden caused by sCJD patients from 2013 to 2017The quality of sCJD patients was studied at first.After excluding uncooperative patients,180 clinical cases of sCJD from January 2017 to July 2018 were included in the study.A retrospective investigation was conducted through telephone inquiring by the staff of China CJD progjram with EQ-5D-3L instrument and Visual analogue scale(VAS).For the rapid progress of disease,patients always have problems with cognition and words.Relatives who knew patients well(parents,spouses or offspring)were inquired.Survival time of patients were collected at the same time.As a result,patients were seriously limited in mobility,self-care and usual activities.Nearly 40%patients had problems with pain/discomfort and almost half patients had problems with anxiety/depression.Healthy utility was calculated according to Chinese value set.The median of the health utility value was 0.206 and VAS score was at a low level,which indicated the severity of physical and mental damages.Moreover,in the survival analysis,it was found that the median survival time of patients with sCJD in China was 7 months,which was consistent with previous studies but shorter than that at a study of Japanese.Living in rural areas and having rapid progressive dementia as foremost symptom were two risk factors for patients’ survival time with RR(95%Confidential Interval)of 1.476(1.008,2.162)and 1.691(1.107,2.583),respectively.In the study of disability weight,a panel of 20 independent experts who have at least middle title with no less than 5 years in their professions and have a basic knowledge about prion diseases was selected.The disability weights for different disability levels were obtain from a two-round Delphi method then the average disability weight for sCJD patients was calculated.Meanwhile,another disability weight obtained from VAS was compared with that of severe Parkinson disease from global burden of disease(GBD).It was found that the disability weights for mild disability,middle disability and severe disability were 0.381,0.745 and 0.937,respectively.The average(95%CI)disability weight for sCJD patients was 0.920(0.914,0.926).The median of expert VAS for sCJD patients was 25,and the DW(P25,P75)was 0.85(0.70,0.92),which was higher than that of severe Parkinson disease in GBD.753 clinical cases of sCJD reported in the surveillance network were included in the study of burden of sCJD from 2013 to 2017.Data such as age,gender,time of onset and time of death were collected through follow-up,hospitals and national disease surveillance systcm of Chinese Center for Disease Control and Prevention.Patients’distribution then was analyzed and years live with disability(YLD),years of life lost(YLL)and disability adjusted life year(DALY)from 2013 to 2017 were calculated as well.Indirect economic burden of sCJD was calculated using the human capital approach.sCJD patients were mainly distributed in the eastern and central areas such as Henan province,Guangdong province,Hebei province,Shandong province,Zhejiang province and Beijing.There are fewer patients in the western area.Patients were mainly at their age of 60～69 years,followed by 45～59 years.The disease burden of sCJD presented a generally rising trend with 16202.617 DALY for five years.YLL accounted for more than 96%of all DALY with 15511.697 DALY In addition,the total YLD for five years was 690.92 DALY,only accounting for about 4-5%of all DALY.Patients aged 45～69 years undertook the main disease burden.The indirect economic burden of sCJD patients was 372.1 million yuan and the indirect cost was 494,134 yuan per capita.Patients aged 45~59 years were the main group who bearing the indirect economic burden.Nonetheless,due to the difficulties in patients’ diagnosis and the scarcity of incidence data in China,the disease burden caused by sCJD patients has been underestimated.The real disease burden still needs to be investigated.Breakthroughs are in urgent need for prion diseases and other rare diseases.