Impact of late-stage CKD and aging on medical utilization in the elderly population: a closed-cohort study in Taiwan.

BACKGROUND: Taiwan has the highest incidence and prevalence of end-stage renal disease globally, especially in the elderly population. The elderly with chronic kidney disease (CKD) also had high mortality. However, population-based research on how the elderly with CKD utilize medical services is still unexplored. We aimed to examine the effects of CKD severity and aging on medical utilizations in the elderly population. METHODS: This retrospective closed cohort study analysed 7868 elderly residents of Kaohsiung City, who participated in the government-sponsored annual physical examination in 1997. The information of medical services and expenses were obtained from the claimed data of the National Health Insurance from 1996 to 1999. CKD was grouped into five stages according to the National Kidney Foundation Kidney Disease Outcomes Quality Initiative (NKF K-DOQI) criteria with modifications. Late-stage CKD was defined as CKD Stages 3 to 5 [estimated glomerular filtration rate (eGFR) below 60 ml/min/1.73 m(2)]. Those subjects with eGFR above 60 ml/min/1.73 m(2) were treated as the reference group. RESULTS: After adjusting all covariates, the odds ratios of hospitalization for elderly subjects with CKD stages 3a, 3b and 4/5 were 1.19 (95% CI = 1.08-1.32), 1.48 (95% CI = 1.26-1.73) and 1.68 (95% CI = 1.21-2.33) compared with the reference group, respectively (P < 0.001). The autoregressive generalized estimating equation analysis revealed that CKD stage had linear associations with medical expenditures during the study period, especially for those elderly subjects with later stage CKD. CONCLUSION: Increases in medical utilizations and expenses were demonstrated in elderly CKD subjects, especially those with late stage CKD. Early prevention of CKD is necessary to lessen the financial impact on medical health care.

Early nephrology referral is associated with prolonged survival in hemodialysis patients even after exclusion of lead-time bias.

BACKGROUND: Early nephrology referral (ER) has been suggested to lower morbidity and mortality in dialysis patients, but the nature of the association has been criticized as possibly because of lead-time bias. This study aims to evaluate if ER is associated with improved survival of hemodialysis patients when the lead-time bias is excluded. METHODS: A total of 192 hemodialysis patients from a medical center and a regional hospital were enrolled in the period from January 1997 to December 2006. ER and late referral (LR) were defined as referral to nephrologists greater or less than 6 months, respectively, before the initiation of hemodialysis. Follow-up of clinical course in all patients was timed from the date at which estimate glomerular filtration rate was estimated to be 15 mL/min/1.73m. The relative overall survival was analyzed by Cox-regression adjusted for their demographic and comorbid conditions RESULTS: Compared with LR patients, ER patients were less likely to have hypoalbuminemia in the beginning of hemodialysis, more likely to have received erythropoietin or phosphate binder therapy, more likely to have a vascular access created before the first hemodialysis, and had a slower rate of renal function decline before hemodialysis. In multivariate analysis, LR (hazard ratio: 2.827; P = 0.049) and diabetes mellitus were both independently associated with increased mortality risk. The survival benefits of ER seem to be originated from the period before initiation of renal replacement therapy. CONCLUSIONS: Our findings show that ER is significantly associated with prolonged survival after exclusion of lead-time bias, which is consistent with ER being associated with better clinical outcomes in hemodialysis patients.

Health-related quality of life in Taiwanese dialysis patients: effects of dialysis modality.

Taiwan has the highest incidence and prevalence of end-stage renal disease worldwide. However, not many studies have focused on the influence of dialysis modality on health-related quality of life (HRQoL) for dialysis patients in Taiwan. This study intended to compare the differences in HRQoL between peritoneal dialysis (PD) and hemodialysis (HD) and to evaluate the effects of dialysis modality on patient HRQoL. A cross-sectional survey using the Taiwan-version 36-item short-form health survey questionnaire (SF-36) was completed by 244 dialysis patients (58 PD and 186 HD patients) at two hospital-based dialysis units in southern Taiwan. Patient characteristics, diagnoses and laboratory data were individually extracted from the annual survey and matched with primary HRQoL data. Multiple linear regression analysis was performed to evaluate the effects of dialysis modality on HRQoL. Compared with HD patients, PD patients had higher scores in six of the eight SF-36 subscales, including physical functioning, role limitations due to physical and emotional problems, bodily pain, vitality, and mental health. However, only role limitations due to emotional problems and bodily pain reached significant difference levels (p < 0.05). After controlling for patient characteristics, comorbid conditions and laboratory values, the bodily pain score was 7.88 points higher for PD patients compared with HD patients, while the social functioning score was 9.00 points higher for HD patients compared with PD patients (p < 0.05). The present study provides cross-sectional confirmation for equivalent levels of HRQoL between PD and HD patients except for the subscales of bodily pain and social functioning. In addition to dialysis modality, HRQoL for dialysis patients may be more related to personal attributes, interactions with multiple diseases, social support and quality of care received. When informing patients about modality choices for dialysis, trade-offs should be discussed and individual preferences for specific aspects of HRQoL should be considered.

Increased risk of mortality in the elderly population with late-stage chronic kidney disease: a cohort study in Taiwan.

BACKGROUND: Taiwan has the world's highest incidence and second highest prevalence of end-stage renal disease (ESRD), particularly in older age groups. However, the transition from chronic kidney disease (CKD) to death or ESRD remains unclear. This study aimed to investigate the impact of late-stage CKD on all-cause and cause-specific mortality by identifying the CKD population. METHODS: This was an observational cohort study (n = 35 529), mean age 75.7 years (SD = 5.3), of participants in the Elderly Health Examination Program (EHEP) in Kaohsiung City, Taiwan, between 2002 and 2004. Estimated glomerular filtration rate (eGFR) was calculated by the simplified modified diet in renal disease equation. Proportional hazard ratios (HR) of mortality associated with late-stage CKD were assessed by Cox regression. RESULTS: The crude prevalence rate of CKD stages 3-5 was 39.4%; 1840 participants (5.18%) died within 2-year follow-up, a mortality rate of 20.3 per 1000 person-years overall and 16.4 per 1000 person-years in the reference group. Higher HR for all-cause and cause-specific mortality were found in the groups with decreased eGFR. Compared with the reference group (eGFR > 60 mL/min/1.73 m(2)), adjusted HR for all-cause mortality were 1.5, 2.1 and 2.6 for groups with eGFR 30-44, 15-29 and < 15 mL/min/ 1.73 m(2), respectively (P < 0.001). Higher HR of mortality due to cardiovascular or renal diseases were also significantly associated with decreased eGFR (P < 0.05). CONCLUSION: Late-stage CKD is a significant risk factor for mortality, especially due to cardiovascular and renal diseases, in elderly Taiwanese. Given the higher prevalence rate of late-stage CKD in the study area, CKD patient mortality was relatively lower, which might reflect underestimation of renal function for patients at early stages of CKD, or partly explain the high ESRD population.