The impact of multiple long-term conditions on mortality, progression to kidney failure and health-related quality of life among people with chronic kidney disease: a multicentre cohort study (NURTuRE-CKD).
Higher numbers of comorbidities in chronic kidney disease patients are linked to increased mortality and worse quality of life, but not to CKD progression.
Where it sits
this study against the rest of the erythropoietin (epo) corpusSummary and findings
This study examined the impact of multiple long-term conditions (MLTC) on mortality, progression to kidney failure, and health-related quality of life (HRQoL) in a cohort of 2996 adults with chronic kidney disease (CKD). The mean age of participants was 62.7 years, with a mean eGFR of 37.3 mL/min/1.73m². Findings indicated that a greater number of comorbidities was associated with higher mortality but not with CKD progression.
Abstract
<h4>Background</h4>Multiple long-term conditions (MLTC) are common in people with chronic kidney disease (CKD). This study examined the impact of MLTC on mortality, CKD progression, and health-related quality of life (HRQoL) in a referred CKD population.<h4>Methods</h4>Adults with non-kidney replacement therapy (KRT)-dependent CKD (stages G1 to G5) were recruited to the prospective NURTuRE-CKD cohort across 16 UK nephrology centres. MLTC was defined as ≥2 conditions (including CKD) and comorbidities categorised into 19 groups. Depression and anxiety were defined using the Hospital Anxiety and Depression Scale, and Cognitive impairment using the Six-item Cognitive Impairment Test. Outcomes were all-cause mortality, CKD progression (eGFR <15 mL/min/1.73m<sup>2</sup> or KRT), and HRQoL (EQ-5D-5L, at two time points). Participants with eGFR < 15 at baseline were excluded from progression analyses.<h4>Results</h4>All 2996 participants had comorbidities at baseline, and therefore MLTC. Mean age was 62.7 (SD ± 14.7) years, mean eGFR 37.3 mL/min/1.73m<sup>2</sup> (SD ± 17.9), and 41% were female. Median baseline comorbidity count was 3 (IQR 2 to 5; range 1 to 19). The commonest baseline comorbidities were hypertension, pain, obesity, hyperuricaemia, diabetes, sarcopenia, and cardiovascular disease. Over a median 1.42 years between baseline and first follow up, the most frequent new comorbidities were pain (285 people (14%)), anxiety and depression (226 (11%)), cognitive impairment (115 (6%)), obesity (98 (5%)), and anaemia (82 (4%)). Increasing comorbidity count was associated with higher mortality (adjusted hazard ratios (vs. 1 comorbidity): 1.37 (2), 1.45 (3), 1.54 (4), and 1.80 (≥5)), with statistical significance at ≥4 comorbidities). Comorbidity number was not associated with CKD progression. Greater number and certain specific comorbidities were associated with worse HRQoL.<h4>Conclusions</h4>Greater comorbidity burden was associated with mortality and worse HRQoL but not CKD progression in this cohort. CKD management should target prevention of additional conditions, prioritise holistic care and focus on MLTC as much as kidney protection.
Background
This study addresses the prevalence and impact of multiple long-term conditions (MLTC) in patients with chronic kidney disease (CKD), a population known to have a high burden of comorbidities. Prior research has indicated that MLTC can complicate the management of CKD and affect patient outcomes. Understanding the relationship between MLTC and mortality, CKD progression, and health-related quality of life (HRQoL) is crucial for improving care strategies in this population.
Methods
The study utilized a prospective cohort design involving 2996 adults with non-kidney replacement therapy-dependent CKD recruited from 16 UK nephrology centers. Participants had a mean age of 62.7 years and a mean eGFR of 37.3 mL/min/1.73m². The primary outcomes measured were all-cause mortality, CKD progression, and HRQoL, assessed using the EQ-5D-5L at two time points.
Results
The primary finding was that increasing comorbidity count was associated with higher mortality, with adjusted hazard ratios of 1.37 for 2 comorbidities, 1.45 for 3, 1.54 for 4, and 1.80 for 5 or more comorbidities, with statistical significance at ≥4 comorbidities. The study did not find a significant association between comorbidity number and CKD progression. Additionally, certain specific comorbidities were associated with worse HRQoL.
Interpretation
The results suggest that while MLTC significantly impacts mortality and HRQoL in CKD patients, they do not appear to influence CKD progression. This contrasts with some prior studies that have linked comorbidities with disease progression. The effect sizes reported, particularly for mortality, are statistically significant but the clinical significance may vary based on individual patient circumstances. Limitations such as the observational nature of the study and potential confounding factors must be considered when interpreting the findings.
Key findings
- Mean age was 62.7 (SD ± 14.7) years, mean eGFR 37.3 mL/min/1.73m² (SD ± 17.9), and 41% were female.
- Median baseline comorbidity count was 3 (IQR 2 to 5; range 1 to 19).
- Adjusted hazard ratios for mortality increased with comorbidity count: 1.37 (2), 1.45 (3), 1.54 (4), and 1.80 (≥5), with significance at ≥4 comorbidities.
- Over a median 1.42 years, the most frequent new comorbidities were pain (14%), anxiety and depression (11%), cognitive impairment (6%), obesity (5%), and anaemia (4%).
- Comorbidity number was not associated with CKD progression.
Limitations
- Observational study design may introduce confounding factors.
- Follow-up duration of 1.42 years may not capture long-term outcomes.
- Single-site recruitment may limit generalizability.
- Potential for selection bias in participants with non-KRT-dependent CKD.