Chronic Kidney Disease and Mortality in Non-alcoholic Fatty Liver Disease Patients

The study examines the relationship between Chronic Kidney Disease and mortality in patients with Non-alcoholic Fatty Liver Disease. The study found that advanced phases of CKD are linked to increased mortality rate in NAFLD patients.

Evidence Based Practice 1
Chronic Kidney Disease is Independently Associated with Increased Mortality in
Patients with Non-alcoholic Fatty Liver Disease
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Evidence Based Practice 2
Abstract
The study by Paik et al. (2018) was aimed at examining the relationship between the varying
phases of Chronic Kidney Disease (CKD) and death in the patient with non-alcoholic fatty
liver disease (NAFLD). The authors used the NHANES-III mortality files and ascertained
NAFLD using hepatic ultrasound. The impact of CKD on cardiovascular death rate was
examined using the multivariable Cox proportional hazard model. The study found out that
overall mortality rate was linked to NAFLD and advanced phases of CKD.
Background Information
Studies have shown CKD to be one of the primary public health issues that cause high death
rates, illness and high treatment costs (Gansevoort et al., 2013). There is also a strong
relationship between CKD and metabolic disorders such as cardiovascular diseases (CVD)
(Gansevoort et al., 2013). NAFLD is a significant liver disorder related to metabolic
syndrome (MS) (Younossi et al., 2018) and at a worldwide prevalence of 25% (Younossi et
al., 2016). The NAFLD patients are estimated to be at a higher risk of CVD (Targher et al.,
2010). The study by Kim et al. (2013) indicated that the primary cause of death in NAFLD
patients was cardiovascular disease.
NAFLD shares several risk factors with chronic illnesses and is regarded as the extrahepatic
manifestation (EHM) of NAFLD (Younossi et al., 2018). Some of the most commonly shared
characteristics of the MS with regard to CKD and NAFLD are insulin resistance, diabetes
mellitus, and obesity (Armstrong et al., 2014). Furthermore, both of the illnesses are linked
with an elevated risk of cardiovascular diseases. Notwithstanding the existence of this tie, its
association with mortality by making use of data that is population-based has not been
adequately addressed.

Evidence Based Practice 3
Critical Approach
Methods and Results
The study design is not expressly identified in the study. However, the study adopted a cohort
design which is of benefit because it is less costly and consumes minimal time than random
control trials (Song and Chung, 2010). Song and Chung (2010) assert that a cohort study is
the most appropriate for assessing and comparing the effectiveness of two or more
interventions. The authors do not, however, justify the use of a cohort approach, thus creating
doubt on not only its appropriateness but also the credibility of the findings (Von Elm et al.,
2014). The authors indicate the source of data “NHANES -III -linked mortality files” which
have been described as comprehensive and reliable in other studies by Younossi et al. (2012).
This also implies that the findings will most likely be reliable. The comparison being made in
the research is between NAFLD and CKD about their relationship about mortality.
Furthermore, the study provides a clear definition of the two variables. The restriction of the
study to subjects that meet the inclusion criteria only minimises selection bias (Song and
Chung, 2010). The results are comprehensive enough to be understood. The rate of
proportion between the exposed and unexposed variables is presented using percentages and
confidence intervals. This makes the results more precise and reduces any bias due to
confounding. Additionally, the observable difference due to the comparison increases the
internal validity of the study (Song and Chung, 2010).
Data Presentation
The analysed data was presented under different themes and compared to each other
according to the findings, and the difference noted. For instance, the characteristics the
cohorts have been presented separately and comparatively with the variables of each section

Evidence Based Practice 4
analysed. This ensures that any possible association between the outcomes and exposure is
clearly defined and thus strengthening the credibility of the findings. Each theme has also
been summarised in table form, thus making it easy to notice the difference by comparing the
outcomes between the exposed and unexposed cohorts. The study has also disclosed the
specific measures used to measure the study variables, statistical methods and analysis. This
increases the reliability and validity of the study (Song and Chung, 2010).
Discussion and Conclusion
The authors discuss and summarise the study outcomes in line with the aim of the study, thus
ensuring that the existing research gap the research intended to fill has been accomplished
and as a result adding more information to the body of knowledge relevant to the area of
study. Furthermore, the findings are compared with previous studies to ascertain any
difference or consistency. This gives strength to the credibility of the findings and is a clear
indication of the depth of the analysis because the results can be compared to those that had
previously been researched and reviewed (Declan Devane and Dip, 2011). The limitation of
the study has been discussed. The major weakness of the research is on the accuracy of the
diagnosis of NAFLD and the absence of follow-up information on the NHANES data. Such
limitations can be potential sources of selection bias because any inaccuracy of NAFLD
might lead to differences between the study groups of comparison. The lack of follow-up
information on the NHANES data may make the study findings not to be up to date, thus
giving an incorrect status and impact of the intervention under assessment (Song and Chung,
2010).
The multiplicity of analyses in the study also increases the validity and reliability of the study
because similar variables are tested using different instruments of measurement. The
NHANES data was based on a large sample size thus increasing the generalizability of the

Evidence Based Practice 5
study. Whereas the restriction of the study population to specific age bracket minimised
selection bias, it also reduced the sample size, a move that further limited the generalizability
of the study (Euser et al., 2009).
Personal Opinion
The findings of the study can be relied upon due to the large and representative sample size
with a similar evaluation of NAFLD. Additionally, the study found out that there exists a
distinct relationship between CKD and NAFLD. These outcomes are in line with previous
studies, thus confirming the credibility of the research.
Quality of the Study
The quality of the study can be rated as above average because there is a connection between
the study aim, methods and results. Additionally, the authors have made attempts to minimise
any selection bias, and the measurement of outcomes have been done using standardised
instruments. The findings are also consistent with previous research.

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References
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Chronic Kidney Disease is Independently Associated with Increased Mortality in Patients
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