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Donald Richardson

Publications and source records attributed to Donald Richardson.

11 recordsLinked to original sources
PubMed2005

Structured conversion from thrice weekly to weekly erythropoietic regimens using a computerized decision-support system: a randomized clinical study.

In view of the recent interest in weekly erythropoietic regimens and the lack of studies directly comparing the available agents, the clinical effectiveness of darbepoetin-alpha (DA) and epoetin-beta (EB), when administered via the subcutaneous route on a weekly basis, after conversion from thrice-weekly subcutaneous EB, was studied. In this 9-mo, single-center, randomized study of an unselected hemodialysis population, anemia was managed with a computerized decision-support system. Per-protocol analysis of the 81 patients in each arm who completed the study showed similar hemoglobin outcomes between treatment arms, both at randomization and at the end of the study. After conversion from thrice-weekly EB to DA (at a ratio of 200 IU:1 microg, at which products are cost-neutral in the European Union), a significant fall in dose from a mean of 0.59 microg/kg per wk after randomization to 0.46 microg/kg per wk in the last month (P = 0.002) was observed; in the comparator arm, the reduction in frequency of administration of EB was associated with a significant dose increase from a mean of 107.5 to 133.2 IU/kg per wk (P = 0.002) during the same period. At hemoglobin stability, mean EB dose was found to be 44% higher than DA dose (when multiplied by 200). Similar significant dose differences were apparent in a modified intention-to-treat analysis. The study demonstrated that, under a decision-support system, both products were capable of adequately maintaining hemoglobin outcome when administered on a weekly basis but with significant dose differences at 9 mo.

Aged↗
PubMed2004

Patient-specific prompts in the cholesterol management of renal transplant outpatients: results and analysis of underperformance.

BACKGROUND: Renal transplant recipients have an increased risk of cardiovascular disease compared with age- and gender-matched controls. It is recommended that "high-risk" patients are treated with hydroxymethylglutaryl CoA reductase inhibitors to reduce cholesterol levels. METHOD: We evaluated the effect of a computer-based decision support algorithm in delivering patient-specific prompts to manage cholesterol in renal transplant outpatients. Data were analyzed retrospectively for a 2-year period with attention to changes in cholesterol levels, prescribing patterns of statins, and causes of underperformance. RESULTS: At baseline, 36.7% of patients achieved a total serum cholesterol level less than 5.0 mmol/L, compared with 67.2% at 2 years, with mean values of 5.6+/-0.1 mmol/L and 4.8+/-0.1 mmol/L (P<0.0001). At baseline, 24% of the patients were receiving statin therapy, increasing to 61% at 2 years. There were no significant changes in creatinine phosphokinase, trough cyclosporine levels, or total cyclosporine dose. Alkaline phosphatase levels increased (166.1+/-3.6-184.6+/-6.1 mmol/L, P=0.009), but remained within the normal clinical range; creatinine clearance increased (58.6+/-1.0-61.0+/-1.2 mL/min, P=0.05). For patients followed concurrently in two units without the algorithm, serum cholesterol measurements decreased from 5.57 mmol/L and 5.34 mmol/L to 5.31 mmol/L and 5.27 mmol/L, respectively (P=0.05), both higher than that achieved contemporaneously at St. James's. Underperformance depended less on medical noncompliance than with systematic features of the methodology and patient preference/collaboration with treatment. CONCLUSIONS: The introduction of the algorithm coincided with a significant reduction in cholesterol levels, an increase in the number of patients receiving appropriate therapy, and no serious adverse effects. Our results illustrate the positive effect of computer-generated prompts and decision support software.

Adult↗
PubMed2003

A randomized, controlled study of the consequences of hemodialysis membrane composition on erythropoietic response.

BACKGROUND: Membrane biocompatibility has long been thought to be relevant to hemodialysis outcomes and, possibly, renal anemia. METHODS: We performed a randomized, controlled, single-center study comparing the consequences on renal anemia of 2 dialyzers of equivalent performance, but different composition, during 7 months. Two hundred eleven patients of an unselected dialysis population of 235 patients gave informed consent to undergo random assignment to either group A (SF170E; modified cellulose triacetate/midflux membrane; Nipro, Osaka, Japan) or group B (HF80LS; polysulfone/high-flux membrane; Fresenius, Bad Homburg, Germany). Anemia management was identical in both treatment groups and followed strict clinical protocols managed by computer algorithms. Dialysis adequacy, hemoglobin (Hb) level, ferritin level, percentage of red blood cell hypochromicity, C-reactive protein (CRP) level, and intravenous iron and epoetin doses were monitored monthly. RESULTS: One hundred seventy-seven patients completed the 7-month study. Equilibrated Kt/V increased in both groups. Hb outcome improved overall, but did not differ between the 2 study groups. Epoetin dose was not significantly different after 7 months compared with baseline in either group. Hb level, epoetin dose, iron status, CRP level, dialysis Kt/V, and residual renal function did not differ between the 2 groups. A slight but significant negative correlation was identified between dialysis Kt/V and Hb level in the population as a whole (Spearman's correlation, -0.16; P = 0.04). CONCLUSION: No significant epoetin-sparing effect was identified through the use of the high-flux polysulfone HF80LS membrane over the modified cellulose triacetate SF170E membrane. Although not a primary outcome for this study, there was a suggestion of benefit of improved Hb level, without increased need for epoetin, through increasing delivered dialysis dose.

Adult↗
PubMed2003

Acquired stuttering following right frontal and bilateral pontine lesion: a case study.

We report neurological information and experimental data regarding acquired neurogenic stuttering in a 57-year-old male following ischemic lesion to the orbital surface of the right frontal lobe and the pons. The experimental data consist of stuttering frequency measures under various conditions that are well known to enhance fluency in most individuals with developmental stuttering. Specifically, we report data for adaptation, unison reading, delayed auditory feedback (DAF), and frequency altered feedback (FAF). This work is the first published report of such a comprehensive examination of a variety of fluency-enhancing conditions in acquired stuttering. The patient read six 200-word texts under different conditions: Six solo readings (Text 1), five unison readings followed by five solo readings (Text 2), five readings with non-altered auditory feedback (Text 3), five readings with 50 ms delayed auditory feedback (Text 4), five readings with increased FAF (Text 5), and five readings with decreased FAF (Text 6). Results indicate that, unlike the typical situation for developmental stuttering, this individual with acquired neurogenic stuttering did not show increased fluency during an adaptation paradigm or under unison, DAF, and FAF conditions. We discuss possible implications of these findings and emphasize the need for further research on acquired neurogenic stuttering.

Acoustic Stimulation↗
PubMed2002

Etiology and treatment of erectile failure in diabetes mellitus.

Men with diabetes are especially prone to neuronal and endothelial disease and are afflicted with erectile dysfunction (ED) at a much higher incidence and prevalence than normal men, with a consequent reduction in quality of life. ED in diabetes results from combinations of impairments from nearly every step in the production of a penile erection. These include the failed transmission of neural signals to and from the spinal cord due to neuropathy resulting in reduced neural nitric oxide (NO) delivery to cavernosal smooth muscle, impaired sinusoidal endothelial cell NO release because of endothelial dysfunction, reduced arterial and arteriolar inflow due to peripheral vascular disease, and failure of relaxation of the corpora from glycation of the elastic fibers. The evaluation of men with diabetes and ED is similar to that in nondiabetic men. It includes assessment of gonadal, neural, arterial, and on occasion, venous function, along with marital and psychological status. Although treatment options for diabetic men with ED have fortunately expanded, the risk factors for ED are the same as those for cardiovascular disease; a flagging penis should raise a red flag of warning to evaluate and treat the risk factors for coronary, cerebral, and peripheral vascular disease, which are common in persons, of either sex, afflicted by diabetes.

Diabetic Angiopathies↗
PubMed2002

Clinical factors influencing sensitivity and response to epoetin.

In patients with chronic kidney disease (CKD), sensitivity to recombinant human erythropoietin (r-HuEPO, epoetin) is of clinical and economic importance. Insight into factors that influence sensitivity and response to epoetin is essential for the adequate management of anaemia. Some factors influencing response to epoetin, such as gender, age, length of time on dialysis, type of dialysis and co-morbidities such as haemoglobinopathy, are not susceptible to clinical intervention. However, many other factors can be controlled. Iron deficiency is the most common factor that limits the response to epoetin. Adequate monitoring of iron status and iron supplementation in patients with CKD will result in a more efficient epoetin response. Increased dialysis dose is associated with improvements in haemoglobin outcome and reduced requirements for epoetin. Dialysis water quality (both chemical and biological) is also important in determining the response to epoetin; 'ultrapure' water reduces epoetin requirements. Some patients, despite adequate epoetin and iron therapy, still have epoetin resistance (low haemoglobin and/or high epoetin requirements). Raised C-reactive protein and/or low albumin may reflect long-standing inflammatory pathology and indicate a need for investigation.

Aging↗