Comparing the impact of older age on outcome in chronic kidney disease of different etiologies: a prospective cohort study

Abstract

BackgroundIn older patients with chronic kidney disease (CKD), the risk of progression to end stage renal disease and cardiovascular death both differ compared to younger patients. This likely reflects differences in case mix and co-morbid burdens. We sought to establish the extent to which age itself is an independent biomarker of adverse outcome in CKD.MethodsThis was an analysis of the Salford Kidney Study, a prospective, longitudinal, observational study of 2,667 patients with eGFR < 60 ml/min/1.73 m2. Patients were divided into four age groups (< 55, 55–65, 65–75 and > 75 years). Within group adjusted hazard ratios for death in older compared to younger patients were calculated for different primary renal diseases. A competing risk model of death and renal replacement therapy (RRT) as outcomes was performed.ResultsThe median age of the cohort was 67.1 years [interquartile range (IQR): 55.6–75.3] and median eGFR 30.8 ml/min/1.73 m2 (IQR: 20.6–43.2). Follow up was 3.5 ± 2.9 years. Overall, the adjusted HR for death in patients aged > 75 years compared to those < 55 years was 4.4 (95% CI 3.4–5.9), p < 0.001. The HR for death differed between primary renal diseases and CKD stages. In diabetic nephropathy, the HR was 3.0 (1.8–5.3, p < 0.001), in glomerulonephritis the HR was 12.2 (5.6–25.5, p < 0.001). The cumulative incidence of RRT was < 0.1 at 10 years for patients > 75 years, compared with 0.50 in those < 55 years. Death was more likely at 20 months in those aged 75 years or older (0.17) than at 10 years in those aged < 55 years (0.10).ConclusionThis study demonstrates that the risk associated with older age shows significant variability between primary renal diseases. This is whilst acknowledging that observational studies carry the risk of hidden bias not adjusted for in the statistical model.Electronic supplementary materialThe online version of this article (10.1007/s40620-018-0529-8) contains supplementary material, which is available to authorized users.

Payor Type is Associated With Increased Rates of Reoperation and Health-care Utilization Following Unicompartmental Knee Arthroplasty: A National Database Study

“…This finding may be explained, in part, by the underdiagnoses of these comorbidities in the Medicaid cohort due to underappropriation of resources in the preoperative period for these at-risk patients. However, these findings may also be explained by the sheer age difference between the two different cohorts—both cardiac and renal comorbidity burden tend to exponentially increase as patients age [ [13] , [14] , [15] ]. Despite this, these findings should call for additional and more extensive preoperative evaluation of publicly insured patients.…”

Aging and Renal Disease: Old Questions for New Challenges

“…The ESRD risk diminished with aging except in patients between 65 and 75 years with eGFRs of 25-35 mL/min per 1.73 m 2 , and in patients up to 85 years with an eGFR <15 mL/min per 1.73 m 2 [ 21 ]. In the United Kingdom, a prospective observational study comparing the impact of old age on outcomes in 2,667 CKD patients with eGFR <60 mL/min/1.73 m 2 found those under 55 years had higher risk of renal replacement therapy (RRT) than death, compared to those >75 years [ 22 ]. Consistent with the above results, we have observed that among 430 patients with stage 3-5 CKD, those aged between 20-39 years and 40-64 years, compared to ≥75 years, exhibited a higher risk of ESRD.…”

“…Indeed, it has been demonstrated that earlier stages of CKD in the elderly are more likely due to age-associated decline in glomerular filtration than real kidney disease [19]. Some studies even suggest older people with CKD may exhibit slower progression and better outcomes [20][21][22][23]. For example, in the United States, among patients with eGFR levels <45 mL/min per 1.73 m 2 , older patients were less likely to have an annual decline in eGFR of >3 mL/min per 1.73 m 2 compared to younger patients [20].…”

Beyond chronic kidney disease: the diagnosis of Renal Disease in the Elderly as an unmet need. A position paper endorsed by Italian Society of Nephrology (SIN) and Italian Society of Geriatrics and Gerontology (SIGG)

“…Identifying CKD allows treat it, and the interventions are effective at any age. This is true either for causal therapy or for the overall therapy of CKD [ 44 ]. Interestingly, many treatable conditions underlying CKD are recognized in the elderly population provided that they are carefully searched for (Table 3 ).…”