Kt/V: achievement, predictors and relationship to mortality in hemodialysis patients in the Gulf Cooperation Council countries: results from DOPPS (2012–18)

Abstract

Background Dialysis adequacy, as measured by single pool Kt/V, is an important parameter for assessing hemodialysis (HD) patients’ health. Guidelines have recommended Kt/V of 1.2 as the minimum dose for thrice-weekly HD. We describe Kt/V achievement, its predictors and its relationship with mortality in the Gulf Cooperation Council (GCC) (Bahrain, Kuwait, Oman, Qatar, Saudi Arabia and the United Arab Emirates). Methods We analyzed data (2012–18) from the prospective cohort Dialysis Outcomes and Practice Patterns Study for 1544 GCC patients ≥18 years old and on dialysis >180 days. Results Thirty-four percent of GCC HD patients had low Kt/V (<1.2) versus 5%–17% in Canada, Europe, Japan and the USA. Across the GCC countries, low Kt/V prevalence ranged from 10% to 54%. In multivariable logistic regression, low Kt/V was more common (P < 0.05) with larger body weight and height, being male, shorter treatment time (TT), lower blood flow rate (BFR), greater comorbidity burden and using HD versus hemodiafiltration. In adjusted Cox models, low Kt/V was strongly related to higher mortality in women [hazard ratio (HR) = 1.91, 95% confidence interval (CI) 1.09–3.34] but not in men (HR = 1.16, 95% CI 0.70–1.92). Low BFR (<350 mL/min) and TT (<4 h) were common; 41% of low Kt/V cases were attributable to low BFR or TT (52% for women and 36% for men). Conclusion Relatively large proportions of GCC HD patients have low Kt/V. Increasing BFR to ≥350 mL/min and TT to ≥4 h thrice weekly will reduce low Kt/V prevalence and may improve survival in GCC HD patients—particularly among women.

Global Epidemiology of End-Stage Kidney Disease and Disparities in Kidney Replacement Therapy

“…This variation in session length reflects an interplay between clinical practice guidelines, reimbursement measures, HD unit policies, and provider and patient preferences [4]. Dialysis treatment time is similarly short in the Gulf Cooperation Council (GCC) countries (Bahrain, Kuwait, Oman, Qatar, Saudi Arabia, and the United Arab Emirates) based on DOPPS data from 2012 to 2018, with a mean of 222 min and 43% prevalence for low treatment time (<240 min) [41].…”

“…Since 1996, an increase in dialysis dose has been observed with lower proportions of HD patients with spKt/V <1.2 in DOPPS countries [43]. Recent DOPPS data from 2015 to 2018 showed that 34% of HD patients from GCC countries had low spKt/V <1.2 versus 5-17% in Canada, Europe, Japan, and the USA [41]. In the USA, Kt/V dose (not dialysis duration) is tied to the CMS' payment policy to dialysis facilities, with 97% of HD patients achieving spKt/V ≥1.2 [1].…”

Achieving dialysis adequacy: A global perspective

“…Use of convective therapies is variable, with 80% patients in Bahrain and 5% in Saudi Arabia receiving HDF. 46 Despite low convective volumes, Kt/ V urea improved in those on HDF. Anemia is well managed-over 90% patients receive erythropoietin preparations and the mean Hb was noted to be more than 10 g/dL across all the GCC countries.…”

“…The DOPPS data from the Gulf Cooperation Council (GCC) countries show that about 34% patients did not meet target Kt/V. 46 This was attributed to the practice of using lower blood flow rates and shorter treatment time. Low Kt/V urea was found to be associated with higher mortality among women.…”

“…Dialysis registry is absent in most countries except Oman, and the United Arab Emirates. The DOPPS data from the Gulf Cooperation Council (GCC) countries show that about 34% patients did not meet target Kt/V 46 . This was attributed to the practice of using lower blood flow rates and shorter treatment time.…”