Biomedical subjects

Andreas Pierratos

Publications and source records attributed to Andreas Pierratos.

24 records · Page 2Linked to original sources

PubMed2002

Cost savings of home nocturnal versus conventional in-center hemodialysis.

BACKGROUND: Home nocturnal hemodialysis (HNHD) can improve clinical and biochemical factors in people with renal failure, but its cost-effectiveness relative to conventional in-center hemodialysis (IHD) is uncertain. We hypothesized that HNHD would provide more dialysis treatments at a lower total cost than IHD. METHODS: A prospective one-year descriptive costing study was performed at two centers in Toronto, Canada, involving patients enrolled from a HNHD program (N = 33), and a matched cohort from an IHD program (N = 23). All costs are expressed as mean weekly amount in Canadian year 2000 dollars. A projected mean annual cost (PMA) was calculated also. RESULTS: The mean number of treatments per week was much higher with HNHD (5.7 vs. 3.0, P = 0.004). Cost categories found to be less expensive for HNHD were staffing (weekly $210 vs. $423, P < 0.001, PMA $10,932 vs. $22,056) and overhead and support (weekly $80 vs. $238, P < 0.001, PMA $4179 vs. $12,393). There was a trend toward lower costs for hospital admissions and procedures (weekly $23 vs. $134, P = 0.355, PMA $1173 vs. $6997) and for medications ($172 vs. $231, P = 0.082, PMA $8989 vs. $12,029). Costs found to be more expensive for HNHD were the cost of direct hemodialysis materials (weekly $318 vs. $126, P < 0.001, PMA $16,587 vs. $6575) and capital costs (weekly $118 vs. $17, P < 0.001, PMA $6139 vs. $871), with a trend toward higher cost for laboratory tests (weekly $33 vs. $26, P = 0.094, PMA $1744 vs. $1364). Physician costs were the same at $128 per week (PMA $6650). The weekly mean total cost for health care delivery was 20% less for HNHD ($1082 vs. $1322, P = 0.006), with projected mean annual costs more than $10,000 lower ($56,394 vs. $68,935). CONCLUSIONS: HNHD provides about three times as many treatment hours at nearly a one-fifth lower cost, with savings evident even when only program and funding-specific costs are considered.

Adult↗

PubMed2002

High urinary excretion of uric acid combined with high excretion of calcium links kidney stone disease to familial hypertension.

BACKGROUND: Past studies identified an association between kidney stone disease (KSD) and hypertension. We recently reported a high occurrence of hypertension in families of patients with hyperuricosuric KSD. As hypercalciura frequently coexists with hyperuricosuria and high urinary excretion of calcium is found in patients with hypertension, we hypothesized that hyperuricosuria that is accompanied by hypercalciuria better describes the familial association between KSD and hypertension. METHODS: Four hundred and eighty-six KSD patients, aged 18-50 years, attending a lithotripsy unit collected a 24-h urine sample for metabolic analysis and provided information on family history of hypertension. The familial occurrence of hypertension was compared among four groups of patients: those who had combined elevation of both urinary calcium and uric acid excretions ("combined" abnormality, n=56), those who had hyperuricosuria without concomitant hypercalciuria ("pure" hyperuricosuria, n=67), those who had hypercalciuria without concomitant hyperuricosuira ("pure" hypercalciuria, n=52), and a control KSD patient group ("other" abnormality, n=311). The prevalence of treated hypertension in patients from the four groups was 16%, 12%, 2%, 10%, respectively. RESULTS: Thirty-four per cent of the patients with the "combined" abnormality had a positive family history of hypertension, defined as two or more first-degree relatives with treated hypertension, that was significantly higher than in patients with either "pure" hyperuricosuira (15%, P<0.02), "pure" hypercalciuria (8%, P<0.001), or patients with "other" abnormality (10%, P<0.001). The adjusted OR for positive family history of hypertension in the "combined" abnormality group compared to the control KSD patient group was 5.6 (2.39-13.30). The prevalence of hypertension in siblings of patients with the "combined" abnormality (13%) was significantly higher than in siblings of patients with either "pure" hyperuricosuria (3%, P<0.001), "pure" hypercalciuria (1%, P<0.001), or siblings of control patients with "other" abnormality (4%, P<0.001). The adjusted OR for hypertension in siblings of a patient with "combined" abnormality compared to a control KSD patient was 3.4 (1.97-5.91). Patients in the "combined" abnormality group were also characterized by significantly elevated urinary sodium, phosphorus, citrate and potassium excretions. CONCLUSIONS: Our data suggest that there is a strong, independent association between familial occurrence of hypertension and the phenotype characterized by combined elevation of both urinary uric acid and calcium excretions. The association is not present in those with "pure" hyperuricosuria or "pure" hypercalciuria. Ascertainment of patients based on this phenotype may identify more homogeneous populations for genetic analysis of hypertension.

Adult↗

PubMed2002

Improvement in ejection fraction by nocturnal haemodialysis in end-stage renal failure patients with coexisting heart failure.

BACKGROUND: Congestive heart failure (CHF) is an independent risk factor for mortality in the end-stage renal disease (ESRD) population. Nocturnal haemodialysis (NHD), a novel mode of renal replacement therapy, may be more effective than conventional haemodialysis in reducing intravascular volume or in removing uraemic toxins with vasoconstrictor or myocardial depressant actions, and may, therefore, improve the left ventricular (LV) systolic function of patients with coexisting cardiac and renal failure. METHODS: To test this hypothesis, we determined, in six patients (mean age+/-SD: 49.5+/-9 years), blood pressure (BP), ejection fraction (EF: radionucleotide angiography), left ventricular mass index (LVMI: echocardiography), LV fractional shortening (FS), and extracellular fluid volume (ECFV: bioelectrical impedance): before and after a mean of 3.2+/-2.1 years following conversion from conventional dialysis (3 days/week x 4 h) to NHD (6 nights/week x 8-10 h). RESULTS: There were significant reductions in systolic and mean arterial BP (138+/-10 to 120+/-9 mmHg, P=0.04; 99+/-6 to 86+/-7 mmHg, P=0.01). There was a significant increase in EF (28+/-12 to 41+/-18%, P=0.01) and a trend to greater LV FS (20+/-10 to 38+/-17%, P=0.06). Post-dialysis ECFV was not affected by dialysis mode (18.5+/-5.1 vs 18.2+/-3.5 l, P=0.76). The number of prescribed cardiovascular medications was reduced (2.2-0.7, P=0.02). CONCLUSIONS: In ESRD patients with systolic dysfunction, NHD leads to a sustained increase of EF and a reduction in the requirement for vasoactive medications in the absence of any reduction in post-dialysis ECFV.

Blood Pressure↗

PubMed2002

Daily hemodialysis: an update.

The interest in daily hemodialysis in the form of short daily hemodialysis and nocturnal hemodialysis has continued to increase over the past few years. A significant number of publications support the evidence for improved outcomes in most of the study areas, including financial benefits. The increased direct cost of the provision of daily hemodialysis seems to be the main obstacle to the wider acceptance of these methods. Convincing data of improved outcomes and evidence of cost efficiency of daily hemodialysis are being generated. These data may increase the interest of the institutional payors as well as of the dialysis industry to create the proper infrastructure for the use of daily hemodialysis. These dialysis regimens promise to have a major impact on the management of end-stage renal disease.

Blood Pressure↗

PubMed2002

Plasma total homocysteine levels among patients undergoing nocturnal versus standard hemodialysis.

Mild hyperhomocysteinemia, a putative risk factor for arteriosclerotic outcomes, is seen in >85% of hemodialysis patients. Therapeutic strategies, including pharmacologic-dose B vitamin supplementation and "high-flux" or "super-flux" hemodialysis, have consistently failed to normalize total homocysteine (tHcy) levels in these patients. Predialysis plasma tHcy levels in 23 patients who were undergoing nocturnal hemodialysis (NHD) six or seven nights/wk were compared with those in 31 patients from the same Canadian dialysis unit who were undergoing chronic standard hemodialysis (SHD) (all <65 yr of age, undergoing thrice-weekly treatments). The SHD patients were similar to typical North American chronic hemodialysis patients with respect to B vitamin status and albumin, creatinine, and tHcy levels. Geometric mean tHcy levels for the NHD patients were significantly lower (12.7 versus 20.0 microM, P < 0.0001), as was the prevalence of mild-to-moderate hyperhomocysteinemia (>12 microM; NHD, 57%; SHD, 94%; P = 0.002). Analysis of covariance adjusted for plasma folate, vitamin B12, and pyridoxal 5'-phosphate levels, age, and gender confirmed that NHD was independently associated with 6.0 microM lower geometric mean tHcy levels (P = 0.001). It is concluded that tHcy levels are significantly lower among NHD patients, compared with SHD patients. Clinical trials will be necessary to confirm that NHD is effective in reducing tHcy levels among patients with dialysis-dependent end-stage renal disease.

Adult↗

PubMedDate not supplied

Reformulating the integrated care concept for the new millennium.

The concept of integrated care advocates a planned approach to predialysis care. Its components include timely referral to a renal care team, timely preparation for dialysis, and timely initiation of dialysis, with peritoneal dialysis (PD) as the initial therapy for suitable patients. This initial therapy may then be followed by timely transfer to hemodialysis (HD) when residual renal function declines or when other PD-related problems occur. We argue that at least three problems exist with the integrated care approach as it is currently being articulated. They are (1) an under emphasis on slowing the rate of progression of chronic kidney disease, aggressive management of cardiovascular risk factors and other comorbidities, and pre-emptive live donor transplantation; (2) a lack of consideration of home HD as an alternate initial therapy; and (3) a lack of discussion about patient choice. We propose a modified version of integrated care that we believe will optimize modality distribution and patient outcomes, while reducing the relative costs per patient treated, compared to the current situation in most countries.

Comprehensive Health Care↗