Sex differences in the development of malignancies among end-stage renal disease patients: a nationwide population-based follow-up study in Taiwan

Sex and gender as predictors for allograft and patient-relevant outcomes after kidney transplantation

BACKGROUND

Sex, as a biological construct, and gender, defined as the cultural attitudes and behaviours attributed by society, may be associated with allograft loss, death, cancer, and rejection. Other factors, such as recipient age and donor sex, may modify the association between sex/gender and post-transplant outcomes.

OBJECTIVES

We sought to evaluate the prognostic effects of recipient sex and, separately, gender as independent predictors of graft loss, death, cancer, and allograft rejection following kidney or simultaneous pancreas-kidney (SPK) transplantation. We aimed to evaluate this prognostic effect by defining the relationship between recipient sex or gender and post-transplantation outcomes identifying reasons for variations between sexes and genders, and then quantifying the magnitude of this relationship.

SEARCH METHODS

We searched MEDLINE and EMBASE databases from inception up to 12 April 2023, through contact with the Cochrane Kidney and Transplant Information Specialist, using search terms relevant to this review and no language restrictions.

SELECTION CRITERIA

Cohort, case-control, or cross-sectional studies were included if sex or gender were the primary exposure and clearly defined. Studies needed to focus on our defined outcomes post-transplantation. Sex was defined as the chromosomal, gonadal, and anatomical characteristics associated with the biological sex, and we used the terms "males" and "females". Gender was defined as the attitudes and behaviours that a given culture associates with a person's biological sex, and we used the terms "men" and "women".

DATA COLLECTION AND ANALYSIS

Two authors independently assessed the references for eligibility, extracted the data and assessed the risk of bias using the Quality in Prognosis Studies (QUIPS) tool. Whenever appropriate, we performed random-effects meta-analyses to estimate the mean difference in outcomes. The outcomes of interest included the Standardised Outcomes in Nephrology-Kidney Transplant (SONG-Tx) core outcomes, allograft loss, death, cancer (overall incidence and site-specific) and acute or chronic graft rejection.

MAIN RESULTS

Fifty-three studies (2,144,613 patients; range 59 to 407,963) conducted between 1990 and 2023 were included. Sixteen studies were conducted in the Americas, 12 in Europe, 11 in the Western Pacific, four in the Eastern Mediterranean, three in Africa, two in Southeast Asia, and five across multiple regions. All but one study focused on sex rather than gender as the primary exposure of interest. The number identified as male was 54%; 49 studies included kidney transplant recipients, and four studies included SPK transplant recipients. Twenty-four studies included adults and children, 25 studies included only adults, and four studies included only children. Data from 33 studies were included in the meta-analyses. Among these, six studies presented unadjusted hazard ratios (HRs) that assessed the effect of recipient sex on kidney allograft loss. The other studies reported risk ratios (RRs) for the pre-defined outcomes. Notably, the decision to restrict the meta-analyses to unadjusted estimates arose from the variation in covariate adjustment methods across studies, lacking a common set of adjusted variables. Only three studies considered the modifying effect of recipient age on graft loss or death, which is likely crucial to evaluating sex differences in post-transplant outcomes. No studies considered the modifying effect of recipient age on cancer incidence or allograft rejection risk. In low certainty evidence, compared with male recipients, being female may make little or no difference in kidney allograft loss post-transplantation (7 studies, 5843 patients: RR 0.91, 95% CI 0.73 to 1.12; I2 = 73%). This was also observed in studies that included time-to-event analyses (6 studies, 238,937 patients; HR 1.07, 95% CI, 0.95 to 1.20; I2 = 44%). Two recent large registry-based cohort studies that considered the modifying effects of donor sex and recipient age showed that female recipients under 45 years of age had significantly higher graft loss rates than age-matched male recipients in the setting of a male donor. In contrast, female recipients 60 years and older had lower graft loss rates than age-matched male recipients, regardless of donor sex. Compared with male recipients, being female may make little or no difference in death up to 30 years post-transplantation; however, the evidence is very uncertain (13 studies, 60,818 patients: RR 0.94, 95% CI 0.81 to 1.09; I2 = 92%). Studies that considered the modifying effect of recipient age and donor sex showed that female recipients had a higher excess death risk than males under 45 years of age in the setting of a male donor. Compared with male recipients, being female may make little or no difference in cancer incidence up to 20 years post-transplantation; however, the evidence is very uncertain (7 studies, 25,076 patients; RR 0.84, 95% CI 0.70 to 1.01; I2 = 60%). Compared with male recipients, being female may make little or no difference in the incidence of acute and chronic kidney allograft rejection up to 15 years post-transplantation (9 studies, 6158 patients: RR 0.89, 95% CI 0.75 to 1.05; I2 =54%; low certainty evidence). One study assessed gender and reported that when compared with men, women experienced better five-year survival in high (HR 0.71, 95% CI 0.59 to 0.87) and middle-income areas (HR 0.82, 95% CI 0.74 to 0.92), with no difference in low-income areas (HR 0.85, 95% CI 0.72 to 1.01). There was considerable uncertainty regarding any association between sex or gender and post-transplant patient-relevant outcomes. This was primarily due to clinical and methodological heterogeneity. The observed clinical heterogeneity between studies could be attributed to diverse patient characteristics within sample populations. As a result of limited sex-stratified demographic data being provided, further investigation of this heterogeneity was constrained. However, factors contributing to this finding may include recipient age, donor age, types, and sex. Methodological heterogeneity was noted with the interchangeable use of sex and gender, outcome misclassification, the use of different measures of effects, inconsistent covariate profiles, and disregard for important effect modification.

AUTHORS' CONCLUSIONS

There is very low to low certainty evidence to suggest there are no differences in kidney and pancreas allograft survival, patient survival, cancer, and acute and chronic allograft rejection between male and female kidney and SPK transplant recipients.

Statin therapy and upper tract urothelial carcinoma risk in hyperlipidemic patients with chronic kidney disease and end-stage kidney disease, a population-based 17-year follow-up study

BACKGROUND

The upper tract urothelial carcinoma (UTUC) risk associated with statin therapy in hyperlipidemic patients with chronic kidney disease (CKD) and end-stage kidney disease (ESKD) remains obscure.

AIM

This retrospective cohort study investigated the UTUC risk for hyperlipidemic patients with CKD or ESKD associated with statin therapy.

METHODS

From the national insurance claims data of Taiwan, we identified hyperlipidemic patients and established three pairs of statin users and non-users sub-cohorts matched by propensity scores: 401,490 pairs with normal kidney function, 37,734 pairs with CKD, and 6271 pairs with ESKD. Incidence rates and hazard ratio (HR) of UTUC were estimated, by the end of 2016, between statin and non-statin cohorts, and between hydrophilic statins users and lipophilic statins users. Time-dependent model estimated adjusted HR, and sub-distribution HR (sHR) accounting for the competing risk of deaths.

RESULTS

The statin-users with ESKD were at increased UTUC risk (sHR 1.98; 95% confidence interval (CI), 1.28-3.06), significant for younger patients (40-64 years). The incidence was twofold greater in women than in men (31.8 versus 15.9 per 10,000 person-years). Receiving lipophilic statins was associated with increased UTUC risk in CKD and ESKD patients, while receiving hydrophilic statins was associated with increased UTUC risk in ESKD patients.

CONCLUSIONS

Patients with ESKD receiving statin were at an increased UTUC risk, significant for younger group (<65 y/o). The positive associations between UTUC and statin persisted in both genders with ESKD, and in therapy with either lipophilic statins or hydrophilic statins. Statin users with ESKD deserve attention for UTUC prevention.

Urine phthalate metabolites are associated with urothelial cancer in chronic kidney disease patients

BACKGROUND

Di(2-ethylhexyl) phthalate (DEHP) is one of the most widely used phthalates and is associated with breast cancer. Ths association between DEHP and other types of cancer is not clear. DEHP may increase matrix metalloproteinase-9 that is critical for the development of urothelial cancer (UC). We examined the association between urinary phthalate metabolites and UC. CKD patients were selected as a control group because CKD patients are more at risk of UC than the general population.

METHODS

In this cross-sectional study, we measured seven urinary phthalate metabolites that are abundant and can be measured using HPLC-MS/MS in Taiwan CKD patients between Jul 2013 and Dec 2015. MiBP (a urinary metabolite of Dibutyl phthalates[DBP]) and MEHHP (a urinary metabolite of DEHP) were described because they are the most abundant phthalate metabolites. The association of phthalate (log-transformed) and UC were analyzed using logistic regression with adjustments for age, gender, renal function, use of traditional Chinese medicine, toxins (dye, organic solvent), and non-steroidal anti-inflammatory drugs.

RESULTS

We measured the urinary MEHHP and MiBP of 496 patients (224 UC and 272 CKD patients). The urinary MEHHP was associated with UC but MiBP was not. Medical history including the use of non-steroid anti-inflammatory drugs, exposure to environmental toxins (dye, paint, and organic solvent), and the use of traditional Chinese medicine was independently associated with UC. The adjusted odds ratio of MEHHP was 1.42 (95% confidence interval: 1.21-1.68).

CONCLUSION

Phthalate urinary metabolite(MEHHP) may be associated with UC in CKD patients and the association is independent of well-known risk factors of UC.

Discovery of Novel Protein Biomarkers in Urine for Diagnosis of Urothelial Cancer Using iTRAQ Proteomics

Urothelial carcinoma (UC) is the ninth most prevalent malignancy worldwide. Noninvasive and efficient biomarkers with high accuracy are imperative for the surveillance and diagnosis of UC. CKD patients were enrolled as a control group in this study for the discovery of highly specific urinary protein markers of UC. An iTRAQ-labeled quantitative proteomic approach was used to discover novel potential markers. These markers were further validated with 501 samples by ELISA assay, and their diagnostic accuracies were compared to those of other reported UC markers. BRDT, CYBP, GARS, and HDGF were identified as novel urinary UC biomarkers with a high discrimination ability in a population comprising CKD and healthy subjects. The diagnostic values of the four novel UC markers were better than that of a panel of well-known or FDA-approved urinary protein markers CYFR21.1, Midkine, and NUMA1. Three of our discovered markers (BRDT, HDGF, GARS) and one well-known marker (CYFR21.1) were finally selected and combined as a marker panel having AUC values of 0.962 (95% CI, 0.94-0.98) and 0.860 (95% CI, 0.83-0.89) for the discrimination between UC and normal groups and UC and control (healthy + CKD) groups, respectively.

Development and validation of a nomogram for urothelial cancer in patients with chronic kidney disease

Urothelial cancer (UC) is a common kidney cancer in Taiwan and patients with chronic kidney disease (CKD) are more at risk for UC than the general population. The diagnostic value of urine analysis and urine cytology is limited, especially in CKD patients. The aim of the study is to develop a nomogram to predict the risk of UC in CKD patients. We enrolled 169 UC patients and 1383 CKD patients from 9 hospitals in Taiwan between 2012 and 2015. CA125, HE4, clinical characteristics, and medical history were analyzed using multivariable logistic regression for its association with UC. A nomogram was developed to predict the risk of UC and was validated using Bootstrap. CA125 was associated with UC in CKD patients (OR: 5.91, 95% CI: 3.24–10.77) but HE4 was not (OR: 1.29, 95% CI: 0.67–2.35). A nomogram based on patients’ age, estimated glomerular filtration rate, CA125 (log transformed), smoking, exposure of environmental toxin, use of nonsteroid anti-inflammatory drugs, and use of traditional Chinese medicine was conducted. The AUC of the nomogram was 0.90 (95% CI: 0.86–0.92, p < 0.01). Serum CA125 may identify UC patients from CKD patients but has limited diagnostic value due to low sensitivity. The diagnostic value of serum CA125 level can be improved by the combination with clinical characteristics including age, renal function, and medical history.

Dialysis-related practice patterns among hemodialysis patients with cancer

RATIONALE AIMS AND OBJECTIVES

With the achievement of longevity in hemodialysis patients, the risk of comorbid cancer has begun to draw attention. In the present study, we examined dialysis-related practice patterns and compared those patterns by cancer status.

METHODS

Using data from the Japan Dialysis Outcomes and Practice Patterns Study phase 4, we evaluated 2153 hemodialysis patients. Baseline cancer status for patients was separated into 3 categories: no cancer, cancer with recent treatment, and cancer without recent treatment. We then assessed variations among hemodialysis patients in dialysis-related practice patterns, including anemia management, management of mineral and bone metabolism disorder, nutritional management, and dialysis treatment, by cancer status.

RESULTS

We observed both similarities and differences in dialysis-related practice patterns among hemodialysis patients, by cancer status. Hemoglobin levels were largely similar for all cancer statuses, although erythropoiesis stimulating agents dose tended to be higher in hemodialysis patients with recent cancer treatment (multivariable adjusted mean difference of erythropoiesis stimulating agents dose: 5.4 × 103 IU/L/month) than in those without cancer. Phosphorus and calcium levels were also similar. Nutrition statuses were similar among cancer statuses, as were dialysis therapies. These results suggested that physicians do not modulate their dialysis-related practices based on whether or not a hemodialysis patient has cancer.

CONCLUSION

Among long-term facility-based hemodialysis patients with cancer, we detected no statistically significant differences to suggest that cancer status affects hemodialysis practice regarding mineral and bone disorder management, nutritional management, and dialysis treatment. Facility-based hemodialysis patients with recent cancer treatment, however, receive a higher dose of erythropoietin-stimulating agent than those without cancer.

Patients with urothelial carcinoma have poor renal outcome regardless of whether they receive nephrouretectomy

The association between urothelial carcinoma (UC) and subsequent ESRD incidence has not been confirmed. This was a population-based study using claims data from the Taiwan National Health Institutes from 1998 to 2010. The study cohort consisted of 26,017 patients with newly diagnosed UC and no history of ESRD, and the comparison cohort consisted of 208,136 matched enrollees without UC. The incidence of ESRD was ascertained through cross-referencing with a registry for catastrophic illnesses. Cox proportional hazard regression analysis was used to estimate the risk of ESRD associated with UC and UC subtype. A total of 979 patients (3.76%) from the UC group and 1,829 (0.88%) from the comparison group developed ESRD. Multivariable analysis indicated that compared with the comparison group, the hazard ratios (HRs) for ESRD were 7.75 (95% confidence interval [CI]: 6.84 to 8.78) and 3.12 (95% CI: 6.84 to 8.78) in the cohort with upper urinary tract UC (UT-UC) and bladder UC (B-UC), respectively. In addition, there were significantly increased risks for ESRD in UC patients receiving and not receiving nephrouretectomies or aristolochic acids (AA). Moreover, the UC patients receiving segmental ureterectomy and ureteral reimplantation had approximately 1.3-fold and 2.4-fold increased risk for ESRD after control for confounders, respectively. Thus, our data indicate that UT-UC and B-UC independently increased the risk for ESRD in patients after considering about nephrouretectomies or aristolochic acids (AA). In addition, UC patients receiving segmental ureterectomy and ureteral reimplantation had increased risk for ESRD.

Is there different risk of cancer among end-stage renal disease patients undergoing hemodialysis and peritoneal dialysis?

Cancer is a global issue in recent decade. Despite this alarming increase in the incidence of cancer, to date, whether the risk of developing cancer differs among peritoneal dialysis (PD) and hemodialysis (HD) patients is still uncertain. In this retrospective cohort study, data were obtained from the National Health Insurance Research Database of Taiwan, which provides coverage to almost 99% of the nation's population. After matching, a total of 4491 (or 3369) incident PD patients and 8982 (or 6738) incident HD patients between 2000 and 2009 were enrolled from the database. In addition, 22,455 (or 16,845) nondialysis patients were selected as a control group. The patients were monitored for the occurrence of cancer until 2010, and their data were analyzed using several different models. In general, the results showed that the risks of hepatocellular, kidney, bladder, extra kidney/bladder urinary tract, and thyroid cancers were higher in dialysis patients. We also compared the risk of cancer between two dialysis groups by using the HD patients as the reference group. The result showed that there is no significant different for each cancer risk between two dialysis groups. In conclusion, dialysis patients had a higher risk of certain types of cancer than those in the nonuremia group. However, there was no significant difference in the cancer risk between the two dialysis groups when compared directly.

Cancer in Korean patients with end-stage renal disease: A 7-year follow-up

BACKGROUND

The effectiveness of dialysis on the incidence of cancer in patients with end-stage renal disease (ESRD) remains to be clarified. In this study, we evaluated the incidence rate and type of cancer among patients with ESRD, compared to the general population, through a prospective 7-year follow-up. We also calculated the cumulative incidence rate of cancer associated with ESRD, with stratification to control for the competing risk of death.

METHODS

This prospective observational cohort study was conducted using data from a nationwide study on patients with ESRD in Korea. A total of 5,235 patients, ≥18 years old, with ESRD were identified from the national registry as being treated by dialysis between August 2008 and December 2014. The standardized incidence ratio (SIR) and cumulative incidence rate of specific cancers were evaluated and compared to the general population.

RESULTS

A total of 5,235 participants were included. During the 7 year observation period, 116 (2.2%) participants had been diagnosed as cancer. The SIR of overall cancer was 0.94 [95% confidence interval (CI), 0.72-1.19] and was comparable to the rate for the general population. Although the digestive organs were the most frequent site of a primary site cancer (N = 39, 33.6%), the SIR was highest for urinary tract cancer [4.7, 95% CI, 2.42-8.19]. The five year standardized cumulative incidence of cancer was higher for females than for males, and for non-diabetic compared to diabetic causes of ESRD. We estimated that the five year standardized cumulative incidence was highest [8.4, 95% CI, 5.07-13.75] in patients with ESRD, caused by glomerulonephritis.

CONCLUSION

A screening program should be necessary for urinary tract cancer in Korean patients with ESRD. Cancer screening programs for patients with ESRD in Korea should be emphasized on female patients and patients with non-diabetic ESRD.

Prognosis of Kidney Transplant Recipients With Pretransplantation Malignancy: A Nationwide Population-Based Cohort Study in Taiwan

OBJECTIVE

The objective of this study was to evaluate the prognosis of kidney transplant recipients with pretransplantation malignancy and the incidence of recurrent malignancy in kidney transplant recipients using claims data from Taiwan's universal health insurance program.

METHOD

A total of 4350 transplant recipients were retrospectively analyzed. The rates of pretransplantation or recurrent malignancy, which was defined by their inclusion in the catastrophic illness patient registry using the International Classification of Diseases, 9th Revision, were evaluated. Cox proportional hazard regression and Kaplan-Meier curves were used for the analyses.

RESULTS

In total, there were 4350 kidney transplant recipients, 52.1% of patients were male, the mean age at transplantation was 45.8 years old, and the percentages of diabetes mellitus, hypertension, hepatitis B viral infection, and hepatitis C viral infection were 14%, 63.2%, 4.2%, and 2.4%, respectively. There were 95 patients (2.2%) with pretransplantation malignancy. The top 3 pretransplantation malignancies, in decreasing order, were urinary tract, kidney, and breast cancers. After kidney transplantation, 10 recipients had recurrent cancer. The overall cancer recurrence rate was 10.5%. These 10 cancers included urothelial carcinoma (n = 5), renal cell carcinoma (n = 3), breast cancer (n = 1), and thyroid cancer (n = 1). Eleven recipients had a secondary cancer. Patients without pretransplantation and post-transplantation malignancy had the best survival. Patients with pretransplantation malignancy had a greater occurrence of cancers and increased mortality regardless of whether or not they had recurrence of cancer.

CONCLUSION

Our results suggest the higher risk of cancer, recurrent or secondary, and mortality after kidney transplantation. Adequate waiting time before transplantation and preventive strategies are strongly suggested in kidney transplant recipients with cancer history.

Use of metformin and risk of kidney cancer in patients with type 2 diabetes

BACKGROUND

The anticancer effect of metformin has been reported in the literature but requires additional confirmation in epidemiologic studies. With respect to kidney cancer scarce data are available. This study investigates whether metformin use in patients with type 2 diabetes mellitus (T2DM) might affect kidney cancer risk.

METHODS

The reimbursement database of the National Health Insurance in Taiwan was used. T2DM patients aged ≥ 40 years and newly treated with either metformin (n=171,753, "ever users of metformin") or other antidiabetic drugs (n=75,499, "never users of metformin") within 1998-2002 were followed for at least 6 months for kidney cancer until 31 December 2009. The treatment effect was estimated by Cox regression using propensity score weighting by inverse probability of treatment weighting approach. Hazard ratios were estimated for ever versus never users, and for tertiles of cumulative duration of metformin therapy.

RESULTS

During follow-up, 917 ever users and 824 never users developed kidney cancer, with respective incidence of 80.09 and 190.30 per 100,000 person-years. The hazard ratio (95% confidence intervals) for ever versus never users is 0.279 (0.254-0.307); and is 0.598 (0.535-0.668), 0.279 (0.243-0.321) and 0.104 (0.088-0.124), respectively, for the first, second, and third tertile of cumulative duration of <14.5, 14.5-45.8 and >45.8 months. In subgroup analyses, the lower risk of kidney cancer associated with metformin use is consistently observed in both sexes, and in patients with or without concomitant use of other antidiabetic drugs.

CONCLUSION

Metformin use is associated with a decreased risk of kidney cancer in patients with T2DM.

Shorter hemodialysis duration is a risk factor for the recurrence of urothelial carcinoma of the bladder in patients on maintenance hemodialysis

PURPOSE

To investigate the association of hemodialysis duration with the recurrence of urothelial carcinoma (UC) of the bladder and overall survival in patients undergoing maintenance hemodialysis (MHD).

PATIENTS AND METHODS

52 bladder cancer patients who underwent MHD at the Xiangya Hospital of The Central South University between 2001 and 2011 were enrolled in the study. The patients were divided into three groups according to hemodialysis duration, and patient mortality and tumor recurrence rates were analyzed. The association of hemodialysis duration with occurrence and recurrence of UC of the bladder was analyzed by Cox regression analysis. Survival was evaluated by the Kaplan-Meier method.

RESULTS

Out of 6266 chronic hemodialysis patients, 52 patients had UC of the bladder after the initiation of hemodialysis for 6 months. The mean age at hemodialysis onset was 55 years (IQR 36, 71). The major complaints were painless gross hematuria and urethral bloody discharge. Tumors were generally large and multifocal. The standardized incidence ratio of UC of the bladder was 43.9 compared with general population, and it was higher in women (76.7) and in the age group 61-65 years (186.6). The mean hemodialysis duration before the diagnosis of bladder cancer was 32 months. 30 (57.7 %) patients received hemodialysis no more than 3 years, 10 (19.2 %) patients received hemodialysis between 3 and 6 years, and 12 (23.1 %) patients received hemodialysis for more than 6 years.

CONCLUSION

Preoperative shorter hemodialysis duration is a risk factor for the occurrence and recurrence of UC of the bladder in patients undergoing MHD.

Increased Risk of Chronic Fatigue Syndrome Following Atopy: A Population-Based Study

Several hypotheses have been proposed to explain the etiopathogenesis of chronic fatigue syndrome (CFS), including immune dysregulation. However, few population-based prospective cohort studies have been conducted on CFS and atopy. We investigated the relationship between atopy and CFS by using a population-based cohort study. In this prospective, population-based cohort study of the National Health Insurance Research Database, we identified 42,558 patients with atopy and 170,232 patients without atopy from 2005 to 2007 with follow-up to 2011. The incidence rates and risks for CFS were estimated using Cox proportion hazards regression. The overall incidence rate of CFS was higher in the atopy cohort compared with the nonatopy cohort (1.37 versus 0.87 per 1000 person-year), with an adjusted hazard ratio of 1.48 (95% confidence interval 1.30-1.69). The risk of CFS in the atopy cohort increased 1.47- to 1.50-fold for each nonexisting comorbidity. Patients with numerous atopic symptoms exhibited a biological gradient of increasing risk for CFS, and the risk changed significantly after adjustment for age, sex, and comorbidities, increasing from 1.46- to 2.59-fold. We revealed that atopy is associated with CFS, particularly in patients with numerous atopic syndromes. The actual mechanism for CFS development in patients with atopy remains unclear and requires further investigation. We recommend researching the subsequent fatigue symptom in patients with atopy, particularly those with multiple atopic syndromes.

Type 1 and type 2 diabetes and cancer mortality in the 2002-2009 cohort of 39,811 French dialyzed patients

End-stage renal disease is a chronic and progressive pathology associated with several comorbidities, particularly diabetes. Indeed, diabetes is the first cause of end-stage renal disease and, in France, 42% of incident patients had diabetes in 2012. In the general population, diabetes is associated with increased cancer risk. The aim of this study was to examine the association between risk of cancer death and diabetes in a large French cohort of patients with end-stage renal disease. Data on all patients with end-stage renal disease who initiated dialysis in France between 2002 and 2009 were extracted from the Renal Epidemiology Information Network registry. The risk of dying by cancer was studied using the Fine and Gray model to take into account the competing risk of death by other causes. We analyzed 39,811 patients with end-stage renal disease. Their mean age was 67.7±15 years, 39.4% had diabetes and 55.3% at least one cardiovascular disease. Compared with the non-diabetic group, patients with diabetes were older and had more cardiovascular and respiratory comorbidities when they started dialysis. Conversely, fewer diabetic patients had also a tumor at the beginning of the renal replacement therapy. Cancer was indicated as the cause of death for 6.7% of diabetic and 13.4% of non-diabetic patients. The Fine and Gray multivariate analyses indicated that diabetes (HR=0.72 95% CI: [0.68-0.95], p<0.001) and also female gender, peritoneal dialysis, cardio-vascular disease and kidney transplantation were associated with decreased risk of death by cancer. In this French cohort of patients with end-stage renal disease, diabetes was not associated with a significant increased risk of dying from cancer. Studies on the incidence of cancer in patients with ESRD are now needed to evaluate the potential association between diabetes and specific malignancies in this population.

Association of dialysis with the risks of cancers

Background

To increase the survival span after dialysis in patients with end-stage renal disease (ESRD), identifying specific cancer risks is crucial in the cancer screening of these patients. The aim of this study was to investigate the risks of various cancers in an incident dialysis group in comparison with a non-dialysis group.

Method

We conducted a nationwide cohort study by using data from the Taiwan National Health Insurance Research Database. Patients who initially received long-term dialysis between January 1997 and December 2004, were selected and defined as the dialysis group and were matched with the non-dialysis patients (control group) according to age, sex, and index year. Competing risk analysis was used to estimate cumulative incidence and subdistribution hazard ratios (SHRs) of the first cancer occurrence.

Results

After consideration for the competing risk of mortality, the dialysis group showed a significantly higher 7-year cancer incidence rate than did the control group (6.4%; 95% confidence interval [CI], 6.0%-6.7% vs 1.7%; 95% CI, 1.4%-2.1%; P <0.001).The modified Cox proportional hazard model revealed that the dialysis group had significantly association with increased risks for all cancers (SHR, 3.43; 95% CI, 3.02-3.88). The risk of cancers was dominated in younger and female patients. Specific cancer risks were significantly higher in the dialysis group particularly in the development of oral, colorectal, liver, blood, breast, renal, upper urinary tract, and bladder cancer than in the control group. Multivariable stratified analyses confirmed the association between long-term dialysis and cancer in all subgroups of patients.

Conclusions

Dialysis is associated with a higher risk of cancer in patients with ESRD. However, cancer screening in ESRD population should be a selective approach, based on individual patient health condition and life expectancy.

Cancer incidence among US Medicare ESRD patients receiving hemodialysis, 1996-2009

BACKGROUND

Patients with end-stage renal disease (ESRD) receiving dialysis have been reported to have increased risk of cancer. However, contemporary cancer burden estimates in this population are sparse and do not account for the high competing risk of death characteristic of dialysis patients.

STUDY DESIGN

Retrospective cohort study.

SETTING & PARTICIPANTS

US adult patients enrolled in Medicare's ESRD program who received in-center hemodialysis.

FACTORS

Demographic/clinical characteristics.

OUTCOMES

For overall and site-specific cancers identified using claims-based definitions, we calculated annual incidence rates (1996-2009). We estimated 5-year cumulative incidence since dialysis therapy initiation using competing-risk methods.

RESULTS

We observed a constant rate of incident cancers for all sites combined, from 3,923 to 3,860 cases per 100,000 person-years (annual percentage change, 0.1; 95% CI, -0.4 to 0.6). Rates for some common site-specific cancers increased (ie, kidney/renal pelvis) and decreased (ie, colon/rectum, lung/bronchus, pancreas, and other sites). Of 482,510 incident hemodialysis patients, cancer was diagnosed in 37,128 within 5 years after dialysis therapy initiation. The 5-year cumulative incidence of any cancer was 9.48% (95% CI, 9.39%-9.57%) and was higher for certain subgroups: older age, males, nonwhites, non-Hispanics, nondiabetes primary ESRD cause, recent dialysis therapy initiation, and history of transplantation evaluation. Among blacks and whites, we observed 35,767 cases compared with 25,194 expected cases if the study population had experienced rates observed in the US general population (standardized incidence ratio [SIR], 1.42; 95% CI, 1.41-1.43). Risk was most elevated for cancers of the kidney/renal pelvis (SIR, 4.03; 95% CI, 3.88-4.19) and bladder (SIR, 1.57; 95% CI, 1.51-1.64).

LIMITATIONS

Claims-based cancer definitions have not been validated in the ESRD population. Information for cancer risk factors was not available in our data source.

CONCLUSIONS

These results suggest a high burden of cancer in the dialysis population compared to the US general population, with varying patterns of cancer incidence in subgroups.

Analysis of potential risk factors for cancer incidence in patients with aristolochic acid nephropathy from Wenzhou, China

BACKGROUND

The purpose of this study was to investigate the cancer incidence in patients with end-stage aristolochic acid nephropathy (AAN).

METHODS

A total of 102 patients with end-stage AAN treated in our hospital between 2004 and 2013 were included in this study. The correlation of cancer incidence with age, gender, dosage of aristolochic acid (AA), the type of renal replacement therapies, and the polymorphisms of quinone oxidoreductase 1 (NQO1) C609T and cytochrome P450 1A1 (CYP1A1) A4889G was examined.

RESULTS

The cancer incidence rate in our patients was 41.2% (42 in 102) including 39 cases of urinary cancer. The mortality rate in the patients with cancer was significantly higher than that in the patients without cancer (31%, 13/42 vs. 11.7%, 7/60, p<0.05). Thirteen patients developed cancer before entering end-stage renal disease (ESRD). Cancer incidence was significantly associated with the dosage of AA consumption (p=0.091). Hemodialysis, peritoneal dialysis and renal transplant did not affect the cancer incidence in our patients differently, but appeared to be associated with cancer at particular locations of urinary system. The patients undergoing hemodialysis seemed to more likely have bladder cancer (72.72%), while the patients receiving peritoneal dialysis appeared to develop cancer predominantly in the upper urinary tract (66.67%).

CONCLUSIONS

The cancer initiation in our patients seems significantly correlate with the dosage of AA consumption. Different renal replacement therapies appear to be associated with cancer at particular locations of urinary system in our patients.

Risk of pneumonia among patients with chronic kidney disease in outpatient and inpatient settings: a nationwide population-based study

Patients with chronic kidney disease (CKD) are more at risk for pneumonia than the general population. Patients with pneumonia are usually treated as outpatients. However, previous studies were conducted on the basis of inpatient pneumonia. This method may underestimate the risk of pneumonia in patients with CKD. Therefore, we investigated the risk of pneumonia among CKD patients in both outpatient and inpatient settings. A total of 15,562 patients with CKD and 62,109 individuals without CKD (matched for age and gender) were taken as subjects in the Longitudinal Health Insurance Database of Taiwan National Insurance from 1996 to 2010. The incidence density rates of inpatient and outpatient pneumonia were calculated. The risk factors associated with pneumonia were analyzed using Cox proportional hazard models with adjustments for confounders. The incidence density rate of pneumonia was 65.6 per 1000 person-years in patients with CKD and 28.4 per 1000 person-years in individuals without CKD. The incidence density rate of inpatient pneumonia was 43.3 per 1000 person-years in patients with CKD and 16.6 per 1000 person-years in individuals without CKD. CKD was associated with increased risk of pneumonia (adjusted hazard ratio [aHR], 1.97; 95% confidence interval [CI], 1.89-2.05; P < 0.001), outpatient pneumonia (aHR, 1.40; 95% CI, 1.31-1.49), and inpatient pneumonia (aHR, 2.17; 95% CI, 2.07-2.29, P < 0.001). Patients' comorbidities, including diabetes, cardiovascular disease (CVD), asthma, and chronic obstructive pulmonary disease (COPD), were independently associated with increased risk of pneumonia.CKD is associated with the increased risk of both outpatient and inpatient pneumonia. This association is independent of comorbid diabetes, CVD, asthma, and COPD.

Chronic fatigue syndrome is associated with the risk of fracture: a nationwide cohort study

PURPOSE

Chronic fatigue syndrome (CFS) is a complex disorder that is associated with unreasonable persistent fatigue. CFS has also been reported to be a possible risk factor for osteopathy. We propose that CFS might be associated with an increased risk of fracture.

METHODS

We used the National Health Insurance Research Database to conduct a prospective cohort study, identifying 3744 patients with a CFS diagnosis (International Classification of Diseases, Ninth Revision, Clinical Modification code 780.71) and 14 976 patients without CFS until 2006, with follow-up observed until the end of 2010.

RESULTS

The incidence rate of fracture was higher in the CFS cohort than in the non-CFS cohort (17.44 vs. 14.53 per 1000 person-year, respectively), with an adjusted hazard ratio of 1.14 (95% confidence interval = 1.00-1.30). The risks of fracture between CFS and non-CFS were shown without comorbidity for each would be elevated than with other comorbidities, particularly in osteoporosis. The patients without osteoporosis in the CFS cohort exhibited a 1.16-fold higher risk of fracture than did those in the non-CFS cohort.

CONCLUSIONS

We propose that CFS-related fracture might not be associated with osteoporosis. The mechanism for developing CFS-related fracture remains unclear; however, we recommend noticing the prevention of fracture for CFS patients before clarifying the aetiology of CFS-related fracture.

The relationship between secondary hyperparathyroidism and thyroid cancer in end stage renal disease: a population based cohort study

OBJECTIVES

We conducted a retrospective cohort study to investigate the risk of cancer in end stage renal disease (ESRD) patients with secondary hyperparathyroidism (HPT).

PATIENTS AND METHODS

This study investigated the elevated overall cancer risk in ESRD patients with secondary HPT in Taiwan. We used a population-based retrospective cohort consisting of original claims data of 1 million beneficiaries randomly sampled from the Taiwan National Health Insurance Research Database (NHIRD). We calculated the hazard ratios (HRs) and 95% confidence intervals (CIs) of cancer in the ESRD with secondary HPT and comparison cohorts, using the Cox proportional hazards regression model.

RESULTS

We observed that ESRD patients with secondary HPT exhibited a 10.1-fold increased risk of thyroid cancer than did ESRD patients without this parathyroid complication, after adjusting for comorbidities (95% confidence interval=1.12-91.0).

CONCLUSION

These phenomena indicate that ESRD patients with secondary HPT are at greater risk of thyroid cancer. Physicians should be alert for occult thyroid cancer in ESRD patients with secondary HPT.