Association of intermittent versus continuous hemodialysis modalities with mortality in the setting of acute stroke among patients with end-stage renal disease.

Patients with end-stage renal disease (ESRD) are 8-10 times more likely to suffer from a stroke compared with the general public. Despite this risk, there are minimal data elucidating which hemodialysis modality is best for patients with ESRD following a stroke, and guidelines for their management are lacking. We retrospectively queried the US Renal Data System administrative database for all-cause mortality in ESRD stroke patients who received either intermittent hemodialysis (IHD) or continuous renal replacement therapy (CRRT). Acute ischemic stroke and hemorrhagic stroke were identified using the International Classification of Diseases 9th Revision (ICD-9)/ICD-10 codes, and hemodialysis modality was determined using Healthcare Common Procedure Coding System (HCPCS) codes. Time to death from the first stroke diagnosis was the outcome of interest. Cox proportional hazards modeling was used, and associations were expressed as adjusted HRs. From the inclusion cohort of 87,910 patients, 92.9% of patients received IHD while 7.1% of patients received CRRT. After controlling for age, race, sex, ethnicity, and common stroke risk factors such as hypertension, diabetes, tobacco use, atrial fibrillation, and hyperlipidemia, those who were placed on CRRT within 7 days of a stroke had an increased risk of death compared with those placed on IHD (HR=1.28, 95% CI 1.25 to 1.32). It is possible that ESRD stroke patients who received CRRT are more critically ill. However, even when the cohort was limited to only those patients in the intensive care unit and additional risk factors for mortality were controlled for, CRRT was still associated with an increased risk of death (HR=1.32, 95% CI 1.27 to 1.37). Therefore, further prospective clinical trials are warranted to address these findings.

Treatment of psoriasis in end-stage renal disease patients is associated with decreased mortality: A retrospective cohort study.

BACKGROUND: Psoriasis impairs the quality of life of approximately 7.5 million Americans and is associated with serious comorbidities. Because of chronic vascular access and epidermal dysfunction, end-stage renal disease (ESRD) patients with psoriasis may be at greater risk for infection, and psoriasis treatment could affect this risk. METHODS: A retrospective cohort analysis was performed using the United States Renal Data System from 2004-2011 to investigate the association of psoriasis with infections common to ESRD patients, as well as the effect of psoriasis treatment on infection risk as well as mortality. RESULTS: A total of 8,911 psoriasis patients were identified. Psoriasis was associated with a significantly increased risk for all queried infections, especially cellulitis (adjusted relative risk = 1.55), conjunctivitis (1.47), and onychomycosis (1.36). Psoriasis treatment (systemic, local, and light) was associated with a significantly decreased risk of some infections. Psoriasis treatment was also correlated with a significantly decreased risk of mortality, with systemic therapies (biologics and other immunosuppressants) showing the greatest reduction (adjusted hazard ratio = 0.55). CONCLUSIONS: These results suggest that psoriasis-ESRD patients may have an increased risk of infection and treatment of psoriasis is associated with a reduced risk of some infections and improved survival.

Incidence, risk factors and distribution of syphilis in the end-stage renal disease population in the USA.

BACKGROUND: Syphilis is a sexually transmitted infection with an incidence of 14.9 cases per 100 000 persons in the USA in 2011. Untreated syphilis may remain quiescent for years but can also result in clinical sequelae, including neurosyphilis. End-stage renal disease (ESRD) patients may be at risk for syphilis due to a higher incidence of risk factors for the disease, including human immunodeficiency virus (HIV). Despite the presence of these risk factors, the incidence of syphilis in the ESRD population has not been reported. To address this issue, we investigated the incidence and risk factors for syphilis in the ESRD population using the United States Renal Data System (USRDS). METHODS: This study analyzed incident ESRD patients from 2004 to 2010. Based on International Classification of Diseases, Ninth Revision codes for syphilis, we determined the incidence and risk factors for syphilis following an inpatient diagnosis. Generalized linear modeling was used to examine the relative risk (RR) for the disease when controlling for demographic and other clinical risk factors. RESULTS: A total of 383 diagnoses of syphilis were identified after screening 759 066 patients. The 8-year incidence of any type of syphilis was 50.45 cases per 100 000 person-years. Other unspecified syphilis (29.77 cases per 100 000 person-years) and neurosyphilis (10.93 cases per 100 000 person-years) were the most common diagnoses. The greatest incidence was found on the East and West Coasts. Patients with the disease were younger and more likely to be black and non-Hispanic. In the final model, the adjusted RR for syphilis was significantly increased with HIV (7.61), hepatitis C (3.57), herpes simplex (2.06) and hepatitis B (1.75). CONCLUSIONS: The incidence of syphilis is >3-fold greater in ESRD patients when compared with the general population and is associated with sexually transmitted viral infections. Neurosyphilis is a common occurrence and is treatable, suggesting that all assessments of confusion in dialysis patients should include screening for the disease.

Incidence and risk factors for HPV-associated cancers in women with end-stage renal disease.

Human papillomavirus (HPV) causes the majority of cervical, anal/rectal, and oropharyngeal cancers in women. End-stage renal disease (ESRD) is also associated with an increased risk of malignancy, but the incidence of and risk factors for HPV-associated cancers in US dialysis patients are not defined. We queried the US Renal Data System for women with HPV-associated cancers and assessed for incidence of cancer diagnosis and association of risk factors. From 2005 to 2011, a total of 1032 female patients with ESRD had 1040 HPV-associated cancer diagnoses. Patients had a mean age of 65 years, were mostly white (63%), and on hemodialysis (92%). Cervical cancer (54%) was the most common, followed by anal/rectal (34%), and oropharyngeal (12%). The incidence of HPV-associated cancers in patients with ESRD increased yearly, with up to a 16-fold increased incidence compared with the general population. Major risk factors associated with the development of any HPV-associated cancer included smoking (adjusted relative risk=1.89), alcohol use (1.87), HIV (2.21), and herpes infection (2.02). Smoking, HIV, and herpes infection were prominent risk factors for cervical cancer. The incidence of HPV-associated cancers in women with ESRD is rising annually and is overall higher than in women of the general population. Tobacco use is a universal risk factor. For cervical cancer, the presence of HIV and herpes are important comorbidities. Recognizing risk factors associated with these cancers may improve diagnosis and facilitate survival. The role of HPV vaccination in at-risk dialysis patients remains to be defined but warrants further study.

Mortality risk after herpes zoster infection in end-stage renal disease patients.

BACKGROUND: End-stage renal disease (ESRD) patients have increased risk of developing herpes zoster (zoster) compared with the general population, but mortality risk is unknown. We assessed the risk of mortality in hospitalized ESRD patients with a diagnosis of zoster from the inpatient hospital files (as opposed to outpatient records) of the United States Renal Data System. METHODS: This study analyzed incident ESRD patients from 2006 to 2009. Based on an International Classification of Diseases, Ninth Revision, Clinical Modification diagnosis code of zoster infection, we determined 2-year mortality following an inpatient diagnosis. Cox proportional hazards models were used to examine the association of mortality and zoster, when controlling for demographic and other clinical risk factors. RESULTS: Zoster was diagnosed in 2784 patients, 51% of whom died within 2 years, with a mean time to death of 8.1 months. Patients who died were more likely to be white and older, score higher on the Charlson Comorbidity Index (CCI) and have other clinical diagnoses besides CCI. Increased risk of death within 2 years was associated with older age (adjusted hazard ratio 1.03), malnutrition (1.31), bacteremia/septicemia (1.16) and increasing CCI (1.10). Zoster vaccine was administered to 27 patients, but the small number precluded analysis of its impact. CONCLUSIONS: Mortality in ESRD patients with an inpatient zoster diagnosis is increased with older age and higher severity of clinical comorbidities. The role of zoster vaccination on mortality in this population remains to be defined.

Clostridium difficile infection in dialysis patients.

Clostridium difficile infection (CDI) is the most common cause of nosocomial diarrhea. Patients with end-stage renal disease (ESRD) may be at increased risk for CDI. Patients with ESRD with CDI have increased mortality, longer length of stay, and higher costs. The present studies extend these observations and address associated comorbidities, incidence of recurrence, and risk factors for mortality. We queried the United States Renal Data System (USRDS) for patients with ESRD diagnosed with CDI, and assessed for the incidence of infection, comorbidities, and mortality. The records of 419,875 incident dialysis patients from 2005 to 2008 were reviewed. 4.25% had a diagnosis of a first CDI. In the majority of patients with CDI positive, a hospitalization or ICU stay was documented within 90 days prior to the diagnosis of CDI. The greatest adjusted relative risk (aRR) of CDI was present in patients with HIV (aRR 2.68), age ≥65 years (aRR 1.76), and bacteremia (aRR 1.74). The adjusted HR (aHR) for death was 1.80 in patients with CDI. The comorbidities demonstrating the greatest risk for death in dialysis patients with CDI included age ≥65 years and cirrhosis (aHR 2.28 and 1.76, respectively). Recurrent CDI occurred in 23.6%, was more common in Caucasians, and in those who were older. CDI is a common occurrence in patients with ESRD, with elderly patients, patients with HIV positive, and bacteremic patients at highest risk for infection. Patients with CDI had nearly a twofold increased risk of death.

Influence of arterial elasticity and vessel dilatation on arteriovenous fistula maturation: a prospective cohort study.

BACKGROUND: Arteriovenous fistula maturation requires dilatation of the anastomosed artery and vein. The factors that affect dilatation and the mechanisms by which dilatation promotes maturation are not understood. This pilot study tested two hypotheses: that low arterial elasticity is associated with maturation failure, and that vessel dilatation is required for adequate fistula blood flow during dialysis. METHODS: Thirty-two patients underwent preoperative measurement of small artery elasticity index, and pre-anastomosis measurement of artery and vein luminal diameters during fistula surgery. Fistulas were considered mature if they were used successfully in three consecutive treatments within 6 months. A mathematical model was used to determine whether vessel dilatation is needed for adequate fistula flow. RESULTS: Six fistulas were excluded from analysis of maturation because dialysis did not begin within 6 months. Twenty-one of the remaining 26 fistulas were located in the upper arm. Six of 26 failed to mature, and all 6 developed stenosis. The average small artery elasticity index was lower in failed than in matured fistulas (2.25 versus 3.71 ml/ mmHg x 100, P = 0.02). Artery and vein diameters of the 32 patients ranged from 2.5 to 5.0 and 3.5 to 7.0 mm, respectively. When the diameters were applied to the mathematical model, predicted fistula flows ranged from 412 to 1380 ml/min. CONCLUSIONS: Low arterial elasticity is associated with stenosis and fistula maturation failure. However, vessel dilatation is not needed for adequate blood flow except at the smaller diameters in this study. We speculate that low elasticity promotes development of stenosis. Larger studies are needed to confirm these promising results and to determine whether therapies directed at improving elasticity can improve maturation.