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W McCready

Publications and source records attributed to W McCready.

7 recordsLinked to original sources

A community-based study of chronic fatigue syndrome.

BACKGROUND: Most previous estimates of the prevalence of chronic fatigue syndrome (CFS) have derived largely from treated populations, and have been biased by differential access to health care treatment linked with sex, ethnic identification, and socioeconomic status. OBJECTIVE: To assess the point prevalence of CFS in an ethnically diverse random community sample. DESIGN AND PARTICIPANTS: A sample of 28,673 adults in Chicago, Ill, was screened by telephone, and those with CFS-like symptoms were medically evaluated. MAIN OUTCOME MEASURES AND ANALYSES: Self-report questionnaires, psychiatric evaluations, and complete medical examinations with laboratory testing were used to diagnose patients with CFS. Univariate and multivariate statistical techniques were used to delineate the overall rate of CFS in this population, and its relative prevalence was subcategorized by sex, ethnic identification, age, and socioeconomic status. RESULTS: There was a 65.1% completion rate for the telephone interviews during the first phase of the study. Findings indicated that CFS occurs in about 0.42% (95% confidence interval, 0.29%-0.56%) of this random community-based sample. The highest levels of CFS were consistently found among women, minority groups, and persons with lower levels of education and occupational status. CONCLUSIONS: Chronic fatigue syndrome is a common chronic health condition, especially for women, occurring across ethnic groups. Earlier findings suggesting that CFS is a syndrome primarily affecting white, middle-class patients were not supported by our findings.

Adult↗

KT/V and protein catabolic rate determination from serial urea measurement in the dialysate effluent stream.

A bloodless technique of evaluating protein catabolic rate (PCR) and KT/V (K, clearance; T, dialysis time; V, urea distribution volume) in hemodialysis patients is presented based on serial measurement of urea in the dialysate effluent stream. PCR follows from equating urea generation and urea removal over a 7 day cycle, changes in body stores being comparatively negligible: PCR = 0.026 [U1 + U2 + U3]/BWdry + 0.17, where U1 is the amount of urea in mmol appearing in the dialysate for each session in the 7 day period. KT/V is obtained from the slope of the natural logarithm of spent dialysate urea concentration-time plot: KT/V = [- slope.T + 3.delta BW/BWdry]/[1 - 0.01786.T(hr], where delta BW = amount ultrafiltered in liters. The dialysate-based approach was validated and compared with conventional urea kinetic modeling (UKM) for 17 patients studied for three consecutive dialyses. The dialysate-based and UKM values of PCR agreed well when in vivo clearance values based on total dialysate collection were used for UKM. KT/V values agreed poorly on a session-by-session basis but were nearly equivalent when averaged for the three dialyses of the week. These findings lay the foundation for UKM automation with a urea sensor in the effluent dialysate stream.

Female↗

Urea kinetic modelling by partial dialysate collection.

Conventional urea kinetic modelling (UKM) has several drawbacks, in particular the complexity of the required calculations and the need for accurate values of parameters which are difficult to measure, such as dialyzer clearance and blood flow. An alternative method of UKM is proposed based on collecting a small fraction of spent dialysate flow for 3 consecutive dialyses. Application of a urea mass balance to the 7 day period permits neglecting changes in body urea stores. Thus no blood sampling is required for most patients. The required calculations are simple and straightforward. The partial dialysate collection (PDC) method was compared to conventional UKM in a 3 patient, 15 week study. Protein catabolic rate (PCR) from PDC was a smooth curve and consistent with dietary estimation for each patient. Conventional UKM gave variable PCR results which were 17-27% higher on average. This discrepancy was attributed to overestimation of dialyzer clearance. PDC was concluded to be more convenient and accurate than conventional UKM and therefore ideal for routine clinical use.

Adult↗