Diversity of the midstream urine microbiome in adults with chronic kidney disease.

PURPOSE: To examine the characteristics of the midstream urine microbiome in adults with stage 3-5 non-dialysis-dependent chronic kidney disease (CKD). METHODS: Patients with non-dialysis-dependent CKD (estimated glomerular filtration rate [eGFR] < 60 ml/min/1.73 m2) and diuretic use were recruited from outpatient nephrology clinics. Midstream voided urine specimens were collected using the clean-catch method. The bacterial composition was determined by sequencing the hypervariable (V4) region of the bacterial 16S ribosomal RNA gene. Extraction negative controls (no urine) were included to assess the contribution of extraneous DNA from possible sources of contamination. Midstream urine microbiome diversity was assessed with the inverse Simpson, Chao and Shannon indices. The diversity measures were further examined by demographic characteristics and by comorbidities. RESULTS: The cohort of 41 women and 36 men with detectable bacterial DNA in their urine samples had a mean age of 71.5 years (standard deviation [SD] 7.9) years (range 60-91 years). The majority were white (68.0%) and a substantial minority were African-American (29.3%) The mean eGFR was 27.2 (SD 13.6) ml/min/1.73 m2. Most men (72.2%) were circumcised and 16.6% reported a remote history of prostate cancer. Many midstream voided urine specimens were dominated (> 50% reads) by the genera Corynebacterium (n = 11), Staphylococcus (n = 9), Streptococcus (n = 7), Lactobacillus (n = 7), Gardnerella (n = 7), Prevotella (n = 4), Escherichia_Shigella (n = 3), and Enterobacteriaceae (n = 2); the rest lacked a dominant genus. The samples had high levels of diversity, as measured by the inverse Simpson [7.24 (95% CI 6.76, 7.81)], Chao [558.24 (95% CI 381.70, 879.35)], and Shannon indices [2.60 (95% CI 2.51, 2.69)]. Diversity measures were generally higher in participants with urgency urinary incontinence and higher estimated glomerular filtration rate (eGFR). After controlling for demographics and diabetes status, microbiome diversity was significantly associated with estimated eGFR (P < 0.05). CONCLUSIONS: The midstream voided urine microbiome of older adults with stage 3-5 non-dialysis-dependent CKD is diverse. Greater microbiome diversity is associated with higher eGFR.

Inflammatory and Metabolic Syndrome Biomarker Analysis of Vascular Outcomes in End-stage Renal Disease.

End-stage renal disease (ESRD) presents a complex syndrome in which inflammatory and metabolic processes contribute to disease progression and development of comorbid conditions. Over $1 trillion is spent globally on ESRD care. Plasma samples collected from 83 ESRD patients prior to hemodialysis were profiled for metabolic and inflammatory biomarker concentrations. Concentrations were compared between groups with and without history of stroke, acute coronary syndrome (ACS), congestive heart failure (CHF), and coronary artery disease (CAD). The 25 patients (30.1%) with history of stroke demonstrated decreased plasma interferon-γ levels (p = 0.042) and elevated plasma resistin, interleukin (IL)-1α, and leptin levels (p = 0.008, 0.021, 0.026, respectively) when compared with ESRD patients without history of stroke. The 14 patients (16.9%) with history of ACS demonstrated elevated plasma IL-6 levels (p = 0.040) when compared with ESRD patients without history of ACS. The 30 patients (36.1%) with history of CHF demonstrated decreased plasma leptin levels (p = 0.031) and elevated plasma IL-1ß levels (p = 0.042) when compared with ESRD patients without history of CHF. Finally, the 39 patients (47.0%) with history of CAD demonstrated elevated plasma IL-1α levels (p = 0.049) when compared with ESRD patients without history of CAD. Plasma biomarker concentration disturbances were observed in ESRD patients with history of stroke, ACS, CHF, and CAD when compared with ESRD patients without such history. Proinflammatory biomarker elevations were seen in stroke, ACS, CHF and CAD, while adipocytokine aberrations were observed in both stroke and CHF. These studies demonstrate that biomarker profiling of vascular comorbidities in ESRD may provide useful diagnostic and prognostic information in the management of ESRD patients.

Non-dialysis dependent chronic kidney disease is associated with high total and out-of-pocket healthcare expenditures.

BACKGROUND: Previous studies have documented the high costs of non-dialysis dependent chronic kidney disease (CKD) but out-of-pocket healthcare expenditures remain poorly explored. This study described total direct and out-of-pocket expenditures for adults with non-dialysis dependent CKD and compared expenditures with those for cancer or stroke. METHODS: This study used data from the 2011-2013 Medical Expenditure Panel Survey, a national survey of healthcare expenditures in the U.S. POPULATION: Expenditures were determined for adults with the following chronic diseases: CKD defined by 585 ICD9 codes (n = 52), cancer (colon, breast or bronchus/lung) (n = 870), or stroke (n = 1104). These represent adults who were aware of their conditions or visited a healthcare provider for the condition during the study period. Generalized linear models were used to estimate the marginal effects of CKD, cancer or stroke on adjusted expenditures compared to adults without CKD, cancer or stroke (n = 72,241) while controlling for demographics and co-morbidities and incorporating the sample weights of the complex survey design. RESULTS: The mean age for group with CKD, cancer or stroke was 65.5, 66.1, and 68.2 years, respectively, while mean age for group without CKD, cancer or stroke was 47.8 years. Median values of total direct and out of pocket healthcare expenditures ranged from as high as $12,877 (Interquartile Range [IQR] $5031-$19,710) and $1439 ($688-$2732), respectively, with CKD, to as low as $1189 (IQR $196-$4388) and $226 (IQR $20-$764) in the group without CKD, cancer or stroke. After adjusting for demographics and comorbidities, the adjusted difference in total direct healthcare expenditures was $4746 (95% CI $1775-$7718) for CKD, $8608 (95% CI $6167-$11,049) for cancer and $5992 (95% CI $4208-$7775) for stroke vs. group without CKD, cancer or stroke. Adjusted difference in out-of-pocket healthcare expenditures was highest for adults with CKD ($760; 95% CI 0-$1745) and was larger than difference noted for cancer ($419; 95% CI 158-679) or stroke ($246; 95% CI 87-406) relative to group without CKD, cancer or stroke. CONCLUSIONS: Total and out of pocket health expenditures for adults with non-dialysis dependent CKD are high and may be equal to or higher than expenditures incurred by adults with cancer or stroke.

Urinary incontinence and diuretic avoidance among adults with chronic kidney disease.

PURPOSE: Diuretics remain an important medication for hypertension management among adults with chronic kidney disease (CKD), but diuretics may also worsen urinary symptoms, especially urinary incontinence (UI). This single-center pilot study examined the prevalence of UI among adults age ≥60 years with CKD using diuretics and assessed diuretic avoidance due to urinary symptoms. METHODS: Patients with non-dialysis-dependent CKD (estimated glomerular filtration rate <60 ml/min/1.73 m(2)) and diuretic use were recruited from outpatient nephrology clinics. Urinary symptoms and diuretic avoidance were assessed using standardized questionnaires. RESULTS: The cohort of 44 women and 54 men had a mean age of 71.8 (8.4) years, and urgency-UI, stress-UI and mixed-UI (the presence of both urgency-UI and stress-UI) were reported by 44.9 % (n = 44), 36.7 % (n = 36) and 26.5 % (n = 26), respectively. Nocturia was noted in 68 % (n = 67). Overall, 15.3 % (6 men and 9 women) reported diuretic avoidance. Avoidance of diuretics was 27.3 % (n = 12), 25.5 % (n = 9) and 34.6 % (n = 9) among participants with urgency-UI, stress-UI and mixed-UI, respectively, while only 6.8 % (n = 3) of participants without any UI reported diuretic avoidance. After adjusting for age, sex and diuretic type (loop vs. others), both urgency-UI (odds ratio 5.9 95 % CI 1.5-22.8) and mixed-UI (odds ratio 5.7; 95 % CI 1.6-19.9) were significantly associated with diuretic avoidance compared to participants without urgency-UI, or mixed-UI, respectively. Stress-UI and nocturia were not significantly associated with diuretic avoidance. CONCLUSIONS: UI is common among older adults with CKD receiving diuretics. Patients with urgency-UI are more likely to avoid diuretics.