Prevalence of Psychiatric Diagnosis in Hospitalized Patients on Dialysis

Patients with end-stage renal disease
(ESRD) may experience depression, anxiety, organic psychiatric disorders,
dementia, disorders related to alcohol or drugs, or schizophrenic disorders,
among others. Patients on maintenance dialysis commonly experience psychiatric
illness, however, it is difficult to determine the true prevalence in that
patient population, creating the possibility that psychiatric disorders in patients
with ESRD may be under-recognized in research and in clinical care.

Data on the prevalence vary; a
systemic review and meta-analysis found prevalence estimates for depression in
patients on dialysis ranged from 1.4% to 94.9%, with a summary prevalence
estimate of 39.3% when depression was assessed by questionnaire and 22.8% when
assessed by interview. Data on psychiatric illnesses in pediatric patients with
ESRD are limited by small study sizes, but, as with adult patients, pediatric
patients with ESRD appear to have higher rates of depression compared with
healthy controls.

There is an association between the
presence of depression or anxiety and lower quality of life in adults and
pediatric patients with kidney disease. There is also an association between
depression in adults with ESRD and lower treatment adherence, more frequent
hospitalizations, and increased mortality. Among pediatric patients on
dialysis, there is an association between increased disease duration and
hospitalizations.

It is unknown how common psychiatric
illnesses are among hospitalized patients with ESRD on dialysis; there are few
data on the associations of those illnesses on outcomes in that patient
population. Researchers, led by Paul L. Kimmel, MD, conducted a study
designed to determine the prevalence of hospitalizations with psychiatric
diagnoses within a year of initiation of treatment for ESRD in adults and
pediatric patients who started treatment from 1996 to 2013. The researchers
also sought to examine the associations between hospitalizations with
psychiatric diagnoses and mortality in adult patients treated with dialysis.
Results were reported in the Clinical Journal of the American Society of
Nephrology [2019;14(9):1363-1371].

The study cohort included 9196
pediatric patients (0-21 years of age), 398,418 adult patients (22-64 years of
age), and 626,344 elderly adult patients (≥65 years of age). Among the
pediatric patients, 64% had a first-year hospitalization; of those, 48% had no
psychiatric diagnoses, 1% had a primary psychiatric diagnosis, and 15% had a
secondary psychiatric diagnosis. Among the adult patients, 66% had a first-year
hospitalization; the percentages of no, primary, and secondary psychiatric
diagnoses were 39%, 2%, and 25%, respectively. Among the elderly adult
patients, 72% had a first-year hospitalization; the percentages for no,
primary, and secondary psychiatric diagnoses were 51%, 2%, and 19%,
respectively.

In the pediatric population
hospitalized with a psychiatric diagnosis, the most common diagnosis was
depression/affective disorders (n=67 patients; 4%). The most common psychiatric
diagnoses among adults was depression/affective disorders (n=2907 patients;
3%), alcohol-related disorders (n=1142; 1%), and drug disorders (n=1041; 1%).
The top primary psychiatric diagnoses among the elderly adults hospitalized
were organic disorders/dementias (n=3680 patients; 3%), depression/affective
disorders (n=1825 patients; 1%), and drug disorders (n=1205; 1%).

Over time, the percentage of patients
hospitalized with psychiatric diagnoses increased, from 9% in 1996-1998 to 26%
in 2011-2013 for pediatric patients, from 19% to 40% for adults, and from 17%
to 39% for elderly adults. Women were more likely than men to have
hospitalizations with psychiatric diagnoses: 17% versus 16% in pediatric
patients; 29% versus 26% in adults; and 25% versus 21% in elderly adults.
Patients with dual eligibility (Medicare and Medicaid) were more likely to have
hospitalizations with psychiatric diagnoses compared with those without dual
eligibility (17% vs 10% in pediatric patients; 30% vs 22% in adults; and 28% vs
21% in elderly adults).

Nearly the entire increase in
hospitalizations with psychiatric diagnoses was due to secondary diagnoses.
This may be due, in part, to the increased number of secondary codes allowed in
Medicare Part A claims from nine in 2009 to 25 in 2010.

Among the pediatric patients, the
percentages with anxiety/personality disorders as secondary diagnoses remained
relatively stable at 13% in 1996-1998 and 16% in 2008-2010, but increased to
24% in 2011-2013. The changes in percentages were similar among adults and
elderly adults: percentages of adults and elderly adults with
anxiety/personality disorders as secondary diagnoses were stable at 9% to 12%
and 7% to 10%, respectively, between 1996-1998 and 2008-2010, but increased to
24% and 20%, respectively, in 2011-2013.

Analyses of the association between
hospitalizations with psychiatric diagnoses and death were limited to a subset
of adults treated with dialysis and ever hospitalized during the first year of
ESRD. The overall mortality rate was 242.4 deaths per 1000 person-years (95%
confidence interval [CI], 241.6-243.2). In patients hospitalized without a
psychiatric diagnosis, the mortality rate was 237.2 (95% CI, 236.2-238.2). In
hospitalized patients with a secondary psychiatric diagnosis, the mortality
rate was 252.1(95% CI, 250.5-253.6). In those with primary psychiatric
diagnoses, the morality rate was 275.3 (95% CI, 269.4-281.3).

Following adjustment for demographic
characteristics, residential area, dual eligibility, Charlson score, and
comorbid conditions at time of dialysis initiation, compared with patients
hospitalized without a psychiatric diagnosis, the hazard ratios of death were
1.29 (95% CI, 1.26-1.32) in all adults hospitalized with primary psychiatric
diagnoses, and 1.11 (95% CI, 1.10-1.12) in all adults hospitalized with
secondary psychiatric diagnoses. Findings were similar for associations between
hospitalizations with psychiatric diagnoses and first year death.

There were some limitations to the
findings cited by the authors, including relying on clinical diagnosis for the
primary and secondary hospitalization diagnoses that are delineated by codes
that may have missed diagnoses in patients treated with dialysis.

In summary, the researchers said, “We
conclude that hospitalizations with psychiatric diagnoses are common in the
United States adult and pediatric patients on dialysis, and such
hospitalizations are associated with higher mortality in adults. This study
likely underestimates the true burden of these conditions within the dialysis
population. Further research is needed to understand their prevalence in cases
where the conditions may not result in (or be coded for) hospitalization. The
findings suggest clinicians who care for hospitalized dialysis patients should
be aware of and prepared to manage psychiatric disorders and associated
negative outcomes within these populations.”

Takeaway Points

1. Researchers conducted a study to
   examine the prevalence of hospitalizations with psychiatric diagnoses within a
   year of initiation of treatment for end-stage renal disease in adult and
   pediatric patients.
2. The prevalence of hospitalizations
   with psychiatric diagnoses increased over time across groups, primarily from
   secondary diagnoses; hospitalizations with psychiatric diagnoses are common in
   both adult and pediatric patient populations in the United States.
3. Hazard ratios of death from all
   causes were higher in all adults on dialysis hospitalized with primary or
   secondary psychiatric diagnoses compared with those hospitalized without
   psychiatric diagnoses.