Study On The Relationship Between Smoking Status And Renal Function/Pathological Changes In Patients With Chronic Kidney Disease

Part I Smoking status of patients with chronic kidney diseaseBackgroundThe adverse effects of smoking on respiratory, cardiovascular system and carciogenesis have been widely accepted. Recent years, the role of smoking in the pathogenesis and pathology in chronic kidney diseases has drawn more and more attention. Tobacco consumption prevails in China.The2002survey indicated that the number of smokers more than15-year-old was about350million. Systemic studies on the relationship between smoking and kidney are lack in our country. This part of our study is a single center suvey on the smoking status of CKD patients in hospital.MethodCKD patients admitted to Shanghai Zhongshan hospital between January2011and November2011with informed consent were included in the study and those with acute kidney injury, acute infection, malignant tumor and mental retardation were excluded. We recorded gender, age, height, body weight, underlying kidney disease and other clinical conditions. We got the information on smoking status, accumulated amount and attitude on cessation from the patients through interviews and questionnaires.ResultsAmong the509patients,173had ever smoked(34.0%).The smoking rate was higher for male patiets(62.9%vs.2.9%, P<0.01),older patiets(39.0%vs.16.1%, P<0.01)and CKD stage3-5patients(46.8%vs.24.6%, P<0.01).87patients were current smokers(17.1%). The current smoking rate was higher for male patiets(32.6%vs.0.4%, P<0.01) and CKD stage3-5patients(22.3%vs.14.1%, P<0.05).82patients were smoking each day(16.1%) and all of them were male patiets. The eachday smoking rate was higher for CKD stage3-5patients(21.3%vs.12.9%, P<0.05). The accumulated smoking amounts of eachday smoker was log transformation packyearsl.26±0.48. The accumulated smoking amounts was bigger for older patiets(log transformation1.37±0.33vs.0.48±0.63, P<0.01),dialysis patiets(log transformation1.65±0.17vs.1.21±0.48, P<0.01) and CKD stage3-5patients(log transformation1.34±0.42vs.1.04±0.51, P<0.01).Among the336nonsmokers,122were associated with second hand smoke(36.3%).Among the173smokers,86had stopped smoking(49.7%).The cessation rate was higher for patiets older than35(52.3%vs.27.8%. P<0.05).Only11.6%of the smokers knew the affect of smoking on kidney.Conclusion The smoking rate among CKD patiets was34.0%. Male, older and CKD stage3-5patients were associated with higher smoking rate and accumulated smoking amount.36.3%of the nonsmokers were associated with second hand smoke. The cessation rate was49.7%and was higher in patients older than35. Only a small part of the patients acknowledged the adverse effect of smoking on kidney. Part Ⅱ The relationship between smoking status and renal function in CKD patientsBackgroundLarge scale community-based prospective studies documented smoking as an important risk factor for the pathogenesis and prognosis of chronic kidney disease and there was a dose-response relationship.But statas on the relationship between smoking and CKD prognosis are lack in our country. This part of our study was designed to investigate the association between GFR and smoking as well as other risk factors. The aim of our study was to illuminate the role of smoking in the prognosis of chronic kidney disease.MethodCKD patients admitted to Shanghai Zhongshan hospital between January2011and November2011with informed consent were included in the study and those with acute kidney injury, acute infection, malignant tumor and mental retarditon were excluded. We recorded gender, age, height, body weight, blood pressure,urine routine, renal function,24hours urinary protein assay, urinary NAG underlying kidney disease and other clinical conditions. We got the information on smoking status, accumulated amount and attitude on cessation from the patients through interviews and questionnares.ResultsThe estimated glomerular filtration rate(eGFR) among the509CKD patients was66.42±42.51ml/min/1.73m2(3.20-233.90ml/min/1.73m2). Univariate analysis indicated the negative association of eGFR with male gender, age, hypertension, smoking and current smoking(r=-0.231, P<0.01; r=-0.433, P<0.01; r=-0.424, P<0.01; r=-0.254, P<0.01; r=-0.115, P<0.05). Multivariate analysis found negative association between eGFR and age, male gender, MAP, hypertension and smoking(P<0.01; P<0.05; P<0.01; P<0.01; P<0.05). The accumulated smoking amount among82current smokers was26.99±19.76packyears and was negatively associated with eGFR(r=-0.479, P<0.01).ConclusionSmoking, current smoking were negatively associated with eGFR. Smoking was an independent risk factor for the deterioration of renal function and severer of deterioration was associated with accumulated smoking amount. Part III The effect of smoking on renal tubulointerstitial and vascular lesions in CKD patientsBackgroundProgressing tubulointerstitial fibrosis is the common final pathway for all kidney disease leading to end stage renal disease(ESRD).Experimental data indicate the adverse effect of smoking on renal tubulointerstitial and vascular lesions. This part of our study was designed to investigate the relationship between smoking status and renal tubulointerstitial and vascular lesions in CKD patients.MethodCKD patients admitted to Shanghai Zhongshan hospital between January2011and November2011for renal biopsy and with informed consent were included in the study and those with acute kidney injury, acute infection, malignant tumor and mental retarditon were excluded. We got the information on smoking status, accumulated amount and attitude on cessation from the patients through interviews and questionnares. We semiquantitatively assessed the tubulointerstitial and vascular lesions and analyzed the effect of smoking status.ResultsAmong the224CKD patients, smokers had higher score of interstitial fibrosis, tubular atrophy, vessel wall thickening and total intersitium-vascular score than nonsmokers(0.77±0.81vs.0.47±0.63, P<0.01;1.34±0.84vs.1.04±0.78, P<0.05;1.27±1.43vs.0.85±1.30, P<0.05;2.13±2.33vs.1.47±2.05, P<0.05).There was no significant difference of interstitial inflammatory cells infiltration and hyaline arterioloslcerosis between two groups. Current smokers had higher score of interstitial fibrosis and tubular atrophy than non-currentsmokers(0.78±0.80vs.0.51±0.67, P<0.05;1.36±0.84vs.1.07±0.79, P<0.05).There was no significant difference of interstitial inflammatory cells infiltration, vessel wall thickening, hyaline arterioloslcerosis and total intersitium-vascular score between two groups. Current smokers had smoked21.21±16.55packyears and the accumulated smoking amount was positively associated with the score of interstitial inflammatory cells infiltration, vessel wall thickening and total intersitium-vascular score(p=0.278, Pv0.05; p=0.369, P<0.05; p=0.366, P<0.05). Among the nonsmokers, patients exposed with second hand smoke had higher score of interstitial inflammatory cells infiltration than those without second hand smoke. There was no significant difference in the score of other intersitium-vascular lesions between these two groups.Conclusion Smoking may play a role in the deterioration of renal tubulointerstitial and vascular lesions in CKD patients. The severity of tubulointerstitial and vascular lesions was increasing with accumulated smoking amount. We also found the affect of passive smoking on renal tubulointerstitial and vascular lesions. Part IV The relationship between smoking status and tubulointerstitial-vascular lesions in patients with IgA nephropathyBackgroundIgA nephropathy is the most common type of primary glomerulonephrititis both in our country. Our previous study found Smoking may play a role in the deterioration of renal tubulointerstitial and vascular lesions, which suggested the possible pathway of smoking affecting IgA nephropathy prognosis. This part of our study was designed to investigate the relationship between tubulointerstitial and vascular lesions with smoking status and other risk factors. The aim of our study was to illuminate the role of smoking in tubulointerstitial and vascular lesions in patients with IgA nephropathyMethodPatients admitted to Shanghai Zhongshan hospital between January2011and November2011for renal biopsy diagnosed as primary IgA nephropathy and with informed consent were included in the study. We got the information on smoking status, accumulated amount and attitude on cessation from the patients through interviews and questionnares. We semiquantitatively assessed the tubulointerstitial and vascular lesions and analyzed the effect of smoking status. We assessed pathological index of by semiquantitative Katafuchi score system.0.5ml random urine sample was collected for urine cadmium test. We analyzed the the role of smoking in tubulointerstitial and vascular lesions in patients with IgA nephropathy.ResultsAmong the90patients patients with IgA nephropathy, smokers had higher score of interstitial inflammatory cells infiltration, interstitial fibrosis, tubular atrophy, vessel wall thickening and total intersitium-vascular score than nonsmokers(1.55±0.59vs.1.22±0.80, P<0.05;1.07±0.78vs.0.48±0.57,P<0.01;1.67±0.76vs.1.14±0.70, P<0.01;1.76±1.43vs.0.85±1.31, P<0.01;7.02±3.06vs.4.29±3.33, P<0.01). There was no significant difference of score of lomerular hypercellularity, glomerular segmental lesions, glomerular sclerosis,hyaline arterioloslcerosis between two groups. Current smokers had higher score of interstitial inflammatory cells infiltration, interstitial fibrosis, tubular atrophy, vessel wall thickening and total intersitium-vascular score than non-currentsmokers (1.57±0.58vs.1.25±0.79, P<0.05;1.10±0.74vs.0.54±0.63, P<0.01;1.15±0.71vs.1.83±0.66, P<0.01;1.81±1.44vs.0.94±1.35, P<0.01;7.17±3.11vs.4.56±3.37, P<0.01). There was no significant difference of score of lomerular hypercellularity, glomerular segmental lesions, glomerular sclerosis,hyaline arterioloslcerosis between two groups. Multivariate analysis indicate positive association between interstitial fibrosis score and smoking, current smoking, hypertension(P<0.01; P<0.05; P<0.01); positive association between tubular atrophy score and smoking, current smoking, hypertension(P<0.01; P<0.01; P<0.01); positive association between vessel wall thickening score and smoking, age(P<0.05; P<0.01); positive association between total intersitium-vascular score and smoking, current smoking, hypertension, age (P<0.01; P<0.05; P<0.01; P<0.05). We did not find significantly association between smoking status and interstitial inflammatory cells infiltration, hyaline arterioloslcerosis in Multivariate analysis. We did not find significant association between urine cadmium and each histopathological parameters. Current smokers had smoked20.62±13.34packyears and the accumulated smoking amount was positively associated with total intersitium-vascular score(p=0.534, P<0.05).ConclusionSmoking was an independent risk factor in the severity of tubulointerstitial and vascular lesions in IgA nephropathy patients. The severity of tubulointerstitial and vascular lesions was increasing with accumulated smoking amount.