Association of physical activity with risk of chronic kidney disease in China:A population-based cohort study

Background:Information on the association between physical activity(PA)and the risk of chronic kidney disease(CKD)is limited.We aimed to explore the associations of total,domain-specific,and intensity-specific PA with CKD and its subtypes in China.Methods:The study included 475,376 adults from the China Kadoorie Biobank aged 30-79 years during 2004-2008 at baseline.An interviewer-administered questionnaire was used to collect the information about PA,which was quantified as metabolic equivalent of task hours per day(MET-h/day)and categorized into 4 groups based on quartiles.Cox regression was used to analyze the association between PA and CKD risk.Results:During a median follow-up of 12.1 years,5415 incident CKD cases were documented,including 1159 incident diabetic kidney disease(DKD)cases and 362 incident hypertensive nephropathy(HTN)cases.Total PA was inversely associated with CKD risk,with an adjusted hazard ratio(HR,95%confidence interval(95%CI))of 0.83(0.75-0.92)for incident CKD in the highest quartile of total PA as compared with participants in the lowest quartile.Similar results were observed for risk of DKD and HTN,and the corresponding HRs(95%CIs)were 0.75(0.58-0.97)for DKD risk and 0.56(0.37-0.85)for HTN risk.Increased nonoccupational PA,low-intensity PA,and moderate-to-vigorous-intensity PA were significantly associated with a decreased risk of CKD,with HRs(95%CIs)of 0.80(0.73-0.88),0.85(0.77-0.94),and 0.85(0.76-0.95)in the highest quartile,respectively.Conclusion:PA,including nonoccupational PA,low-intensity PA,and moderate-to-vigorous-intensity PA,was inversely associated with the risk of CKD,including DKD,HTN,and other CKD,and such associations were dose dependent.

Associations of polygenic risk scores with risks of stroke and its subtypes in Chinese

Background and purpose Previous studies,mostly focusing on the European population,have reported polygenic risk scores(PRSs)might achieve risk stratification of stroke.We aimed to examine the association strengths of PRSs with risks of stroke and its subtypes in the Chinese population.Methods Participants with genome-wide genotypic data in China Kadoorie Biobank were split into a potential training set(n=22191)and a population-based testing set(n=72150).Four previously developed PRSs were included,and new PRSs for stroke and its subtypes were developed.The PRSs showing the strongest association with risks of stroke or its subtypes in the training set were further evaluated in the testing set.Cox proportional hazards regression models were used to estimate the association strengths of different PRSs with risks of stroke and its subtypes(ischaemic stroke(IS),intracerebral haemorrhage(ICH)and subarachnoid haemorrhage(SAH)).Results In the testing set,during 872919 person-years of follow-up,8514 incident stroke events were documented.The PRSs of any stroke(AS)and IS were both positively associated with risks of AS,IS and ICH(p<0.05).The HR for per SD increment(HR_(SD))of PRSAS was 1.10(95%CI 1.07 to 1.12),1.10(95%CI 1.07 to 1.12)and 1.13(95%CI 1.07 to 1.20)for AS,IS and ICH,respectively.The corresponding HR_(SD) of PRS_(IS) was 1.08(95%CI 1.06 to 1.11),1.08(95%CI 1.06 to 1.11)and 1.09(95%CI 1.03 to 1.15).PRS_(ICH) was positively associated with the risk of ICH(HR_(SD)=1.07,95%CI 1.01 to 1.14).PRSS_(AH) was not associated with risks of stroke and its subtypes.The addition of current PRSs offered little to no improvement in stroke risk prediction and risk stratification.Conclusions In this Chinese population,the association strengths of current PRSs with risks of stroke and its subtypes were moderate,suggesting a limited value for improving risk prediction over traditional risk factors in the context of current genome-wide association study under-representing the East Asian population.

Associations of muscle mass,strength,and quality with all-cause mortality in China:a population-based cohort study

Background It remains unclear about the association of muscle mass,strength,and quality with death in the general Chinese population of diverse economical and geographical backgrounds.The present study aimed to comprehensively examine such associations across different regions in China.Methods Based on the China Kadoorie Biobank study,the present study included 23,290 participants who were aged 38 to 88 years and had no prevalent cardiovascular diseases or cancer.Muscle mass and grip strength were measured using calibrated instruments.Arm muscle quality was defined as the ratio of grip strength to arm muscle mass.Low muscle mass,grip strength,and arm muscle quality were defined as the sex-specific lowest quintiles of muscle mass index,grip strength,and arm muscle quality,respectively.Cox proportional hazards models yielded hazard ratios(HRs)and 95%confidence intervals(CIs)for risks of all-cause mortality in relation to muscle mass,strength,and quality.Results During a median follow-up of 3.98 years,739 participants died.The HR(95%CI)of all-cause mortality risk was 1.28(1.08–1.51)for low appendicular muscle mass index,1.38(1.16–1.62)for low total muscle mass index,1.68(1.41–2.00)for low grip strength,and 1.41(1.20–1.66)for low arm muscle quality in models adjusted for sociodemographic characteristics,lifestyle factors,and medical histories.Conclusion Low muscle mass,grip strength,and arm muscle quality are all associated with short-term increased risks of mortality,indicating the importance of maintaining normal muscle mass,strength,and quality for general Chinese adults.