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Potentially pr eventable complications
of urinary tract infections, pr e ssure ar eas,
pneumonia, and delirium in hospitalised
dementia patients: r etrospective cohort
study
Kasia Bail,
1
Helen Berry,
2
Laurie Grealish,
1
Brian Draper,
3
Rosemary Karmel,
4
Diane Gibson,
1
Ann Peut
5
To cite: Bail K, Berry H,
Grealish L, et al. Potentially
preventable complications
of urinary tract infections,
pressure areas, pneumonia,
and delirium in hospitalised
dementia patients:
retrospective cohort study.
BMJ Open 2013;3:e002770.
doi:10.1136/bmjopen-2013-
002770
▸
Prepublication history and
additional material for this
paper is available online. To
view these files please visit
the journal online
(http://dx.doi.org/10.1136/
bmjopen-2013-002770).
▸ Additional material is
published online only. To
view please visit the journal
online (http://dx.doi.org/10.
1136/bmjopen-2013-
002770).
Received 21 February 2013
Revised 8 May 2013
Accepted 8 May 2013
This final article is available
for use under the terms of
the Creative Commons
Attribution Non-Commercial
2.0 Licence; see
http://bmjopen.bmj.com
For numbered affiliations see
end of article.
Correspondence to
Dr Kasia Bail; kasia.bail@
canberra.edu.au
ABSTRACT
Objectives:
To identify rates of potentially preventable
complications for dementia patients compared with
non-dementia patients.
Design: Retrospective cohort design using hospital
discharge data for dementia patients, case matched on
sex, age, comorbidity and surgical status on a 1 : 4
ratio to non-dementia patients.
Setting: Public hospital discharge data from the state
of New South Wales, Australia for 2006/2007.
Participants: 426 276 overnight hospital episodes for
patients aged 50 and above (census sample).
Main outcome measures: Rates of preventable
complications, with episode-level risk adjustment for
12 complications that are known to be sensitive to
nursing care.
Results: Controlling for age and comorbidities,
surgical dementia patients had higher rates than non-
dementia patients in seven of the 12 complications:
urinary tract infections, pressure ulcers, delirium,
pneumonia, physiological and metabolic derangement
(all at p<0.0001), sepsis and failure to rescue (at
p<0.05). Medical dementia patients also had higher
rates of these complications than did non-dementia
patients. The highest rates and highest relative risk for
dementia patients compared with non-dementia
patients, in both medical and surgical populations,
were found in four common complications: urinary
tract infections, pressure areas, pneumonia and
delirium.
Conclusions: Compared with non-dementia patients,
hospitalised dementia patients have higher rates of
potentially preventable complications that might be
responsive to nursing interventions.
INTRODUCTION
Rates of adverse events remain a steadfast indi-
cator of quality and safety for public hospitals.
1
Older people are known to be particularly vul-
nerable to complications, with a Canadian
study finding that 14% of older adults experi-
enced an adverse event while in hospital.
2
In an Australian study, complications such as
ARTICLE SUMMARY
Article focus
▪ Dementia patients are vulnerable to complica-
tions of hospitalisation, which contributes to
increased length of stay, mortality and higher
rates of transfer to residential care.
▪ The extent to which specific potentially prevent-
able complications occur for dementia patients
has not been elucidated.
▪ This article establishes rates of preventable com-
plications for 12 complications that are known to
be sensitive to nursing care.
Key messages
▪ Hospitalised dementia patients have much higher
rates of potentially preventable complications,
particularly urinary tract infections, pressure
ulcers, pneumonia and delirium, than do hospi-
talised non-dementia patients.
▪ These complications are known to be responsive
to nursing care.
▪ Further exploration of the role of nursing in pre-
venting these complications in dementia patients
is warranted.
Strengths and limitations of this study
▪ Study strengths include: an internationally estab-
lished coding rule for patient-level risk adjust-
ment; a linked administrative data approach
which captures any person with documented
dementia in a hospital episode over a 2-year
period; an extremely large and representative
sample, and a broad age range including patients
aged 50 and above.
▪ The study is limited to one Australian jurisdiction
(New South Wales, Australia’s largest state), and
has the usual limitations of hospital administra-
tive data for the documentation of diagnoses.
Bail K, Berry H, Grealish L, et al. BMJ Open 2013;3:e002770. doi:10.1136/bmjopen-2013-002770 1
Open Access Research
urinary tract and respiratory infections, altered mental
state, electrolyte disorders and pressure ulcers were more
common in patients aged over 70 years.
3
Factors that
might contribute to this include multiple chronic diseases,
longer hospitalisations,
45
more frequent use of invasive
devices, such as urinary catheters,
6
more complicated dis-
eases, less physiological reserve, an increased risk of falls
and fractures,
7
and atypical presentations of illness.
8
There has been limited research into complications in
dementia patients in hospital,
5
but a systematic review
found that dementia patients are older, require more
hours of nursing care, have longer hospital stays and
are more at risk of delayed discharge and functional
decline during admission.
6
To date, most study cohorts
have been recruited from medical wards.
6
In a
Taiwanese retrospective coh ort study, Hu et al
9
found
that dementia patients who underwent surgery had a sig-
nificantly higher overall postoperative complication rate
and also a higher incidence of postoperative complica-
tions that were less likely to be identified in their initial
stage. These included acute renal failure, pneumonia,
septicaemia, stroke and urinary tract infection. These
potentially preventable complications have been demon-
strated to be sensitive to nursing—that is, associated with
modifiable characteristics of the nursing work environ-
ment, such as registered nurse skill mix and nurse
burnout—in both Europe
10
and America.
11
More infor-
mation regarding the rates of potentially preventable
complications, which may be sensitive to nursing care
for hospitalised dementia patients to confirm these find-
ings internationally, would be useful for decisions
related to resource allocation in healthcare.
METHODS
This study was nested in the Australian Hospital
Dementia Services Project
12
using New South Wales
(NSW) hospital discharge data from the 2006/2007
financial year for all public hospital overnight discharges
(less than 90 days’ length of stay) for episodes of care
for people aged 50 and over. An episode of hospital care
may be defined as a period in a particular hospital of a
particular care type (eg, acute or rehabilitation) in a par-
ticular hospital. A hospital stay is the period from admis-
sion into the hospital system to discharge from the
system, or death in the hospital (eg, may include mul-
tiple care types and/or hospitals).
Consequently, a stay in hospital may include several
episodes of care: on average, there were 1.18 episodes
per stay.
13
Dementia patients were identified via a
person identifier as ever having dementia documented
as a principal or additional diagnosis in any hospital stay
over a 2-year period, offering a high capture rate and
minimising selection bias.
13
NSW is Australia’s most
populous state with a diverse population from metropol-
itan to remote areas and a range of hospital-based and/
or community-based dementia services. In 2007, 942 100
people or 13.7% of NSW residents were aged 65 years
and over.
14
Consequently, NSW provides both system
and population diversity.
Dementia patients were case matched on age group,
sex, surgical status and Charlson comorbidities on a ratio
of one dementia patient to four non-dementia patients.
The Charlson index is widely used to limit the confound-
ing influence of comorbidities on the prediction of
1-year mortality.
15
The index accounts for diabetes, hemi-
plegia or paraplegia, any cancer, HIV/AIDS and major
cardiovascular, renal, rheumatic, peptic ulcer and liver
diseases and its predictive validity in older people is com-
parable to that of a self-report.
16
Dementia is usually also
included in Charlson indexing but was excluded for the
purpose of comorbidity matching in this study. Where
there were insufficient controls to achieve four non-
dementia patients for each dementia patient, ‘bootstrap-
ping’ was utilised, where matching controls were rando-
mised and then used more than once. This maximises
the use of the existing population of cases and controls
and maintains the benefits at a ratio of 1 : 4.
17
This pro-
cedure was primarily necessary in the 85+ age group.
Using internationally valid patient-level and risk-adjusted
‘coding rules for adverse outcomes’
18–20
(see table 1), 12
potentially preventable complications sensitive to nursing
care were examined. These coding rules have been used
in Australia, New Zealand, Belgium and the USA over the
last 20 years and also been translated from the
International Classification of Diseases, Ninth Edition
(ICD-9) to ICD-10.
19
Patients are grouped according to
medical or surgical status using the Australian Refined
Diagnosis Related Groups (AR-DRGs) V5.2 code, which
incorporates the ICD, Tenth Edition, Australian
Modification (ICD-10-AM) 5th Edition,
21
where surgery is
inclusive of ‘other’ procedures such as gastroscopy and
intubation. The coding rules utilise administrative data to
exclude patients who are at risk of developing a particular
condition due to their underlying aetiology. In this way,
the episodes of complications examined are less likely to
have occurred from patient risk, and more likely to be
related to hospitalisation. For example, patients who have
paralysis as a primary or secondary diagnosis are less
mobile than other patients and are therefore excluded
from the complication ‘pressure ulcer’; patients with a
primary or secondary diagnosis of any kidney or bladder
condition are excluded from the complication ‘urinary
tract infection’. Consequently, each complication has a dif-
ferent sample size, based on exclusions and inclusions.
Surgical and medical cohorts are analysed separately.
The statistical package SAS EG V.9.2 was used.
Pearson’s χ
2
test of independence demonstrated the
magnitude of association and goodness-of-fit of the rela-
tive risk (RR) between dementia and non-dementia
patients, where RR was calculated using the residuals
adjusted for sample size and the 1 : 4 case-to-control
ratio. Missing data were rare in the variables used in this
analysis. Diagnosis information was missing in less than
0.2% and sex in less than 0.001% of records for 2006–
2007; AR-DRGs data were always present. The dataset
2
Bail K, Berry H, Grealish L, et al. BMJ Open 2013;3:e002770. doi:10.1136/bmjopen-2013-002770
Potentially preventable complications in hospitalised dementia patients
was extracted from the source administrative data based
on age (50+), and therefore patient age is never missing
in this analysis. Owing to the very low level of missing
data, records with missing information were excluded
from the analysis where relevant.
RESULTS
There were 44 488 (10.44%) hospital episodes for
dementia patients in NSW over the period 2006–2007,
compared with 381 788 for non-dementia patients.
Surgery was much less commo n in dementia patients
Table 1 Coding rules for adverse outcomes (only 4 of the 12 complications shown for readability)
Complication
Inclusion criteria
Any secondary diagnosis of
Exclusion criteria
Any primary diagnosis or major diagnostic
category (MDC) of
Urinary tract
infection
Urinary tract infection, non-specified site
Infection and inflammatory reaction due to implant,
prosthesis and graft in urinary system
Urinary tract infection, non-specified site
Infection and inflammatory reaction due to implant,
prosthesis and graft in urinary system
Streptococcal sepsis, other sepsis
Bacterial infection, unspecified
Kidney and urinary tract (MDC)
Female reproductive system (MDC)
Pregnancy, childbirth and puerperium (MDC)
Newborn and other neonates (perinatal period;
MDC)
Any primary or secondary diagnosis of:
Pregnancy
Abortion
Pressure ulcer Decubitus ulcer and pressure area Decubitus ulcer and pressure area
Skin, subcutaneous tissue and breast (MDC)
Any primary or secondary diagnosis of:
Hemi/quadriplegia
Pneumonia Pneumonitis due to solids and liquids
Post procedure respiratory disorder, unspecified
Other post procedural respiratory disorders
Hypostatic pneumonia, unspecified
Pneumonia, haemophilus influenza and bacterial
pneumonia
Other bacterial pneumonia
Bacterial pneumonia, unspecified
Bronchopneumonia, unspecified
Other pneumonia, organism unspecified
Pneumonia, unspecified
Viral pneumonia, not elsewhere classified
Pneumonia due to Streptococcus pneumoniae
Bacterial pneumonia due to flu
Other bacterial pneumonia
Bacterial pneumonia, unspecified
Pneumonia due to Mycoplasma pneumoniae
Due to other infectious organisms
In diseases classified elsewhere
Bronchopneumonia, unspecified
Other pneumonia, organism unspecified
Pneumonia, unspecified
Influenza
Influenza, virus not identified
Pneumonitis due to food and vomit
Postprocedural respiratory disorder, unspecified
Other postprocedural respiratory disorders
Hypostatic pneumonia, unspecified
Respiratory system (MDC)Any primary or
secondary diagnosis of:
Immunodeficiency
Systemic autoimmune disease, unspecified
HIV
Delirium Coma, unspecified
Stupor, semicoma
Delirium, unspecified
Other specified dissociative (conversion) disorders
Adjustment disorders
Reaction to severe stress, unspecified
Coma, unspecified
Stupor, semi-coma
Delirium, unspecified
Other specified dissociative (conversion) disorders
Adjustment disorders
Reaction to severe stress, unspecified
Nervous system (MDC)
Mental diseases and disorders (MDC)
Alcohol/drug use or induced mental disorders
(MDC)
MDC, major diagnostic category.
Bail K, Berry H, Grealish L, et al. BMJ Open 2013;3:e002770. doi:10.1136/bmjopen-2013-002770
3
Potentially preventable complications in hospitalised dementia patients
(12%) than in non-dementia patients (27%). The
average surgical dementia patient age was 81 with a
Charlson index of 1.04 (indicating that most dementia
patients had one comorbidity in addition to dementia),
whereas the average surgical non-dementia patient age
was 68 with a lower Charlson index of 0.89. Dementia
patients had more hospital episodes with potentially pre-
ventable complications than did non-dementia patients,
and this difference was higher in the surgical population.
Table 2 shows the results for medical and surgical
patients. Medical dementia patients (ie, those who did
not undergo surgery) had higher rates of delirium (RR
2.83), urinary tract infections (RR 1.79), pressure ulcers
(RR 1.61), pneumonia (RR 1.37; all at p<0.0001), as well
as sepsis (RR 1.34) and failure to rescue (death follow-
ing sepsis, shock, gastrointestinal bleeding, deep vein
thrombosis or pneumonia; RR 1.24; at p<0.05), com-
pared with non-dementia patients. There was no signifi-
cant difference between medical dementia and
non-dementia patients for shock or gastrointestinal
bleeding. Deep vein thrombosis/pulmonary embolism
was the only complication found to be significantly less
common in dementia patients (RR 0.82; at p<0.05).
Surgical dementia patients had higher rates of delir-
ium (RR 3.10), urinary tract infections (RR 2.88), pres-
sure ulcers (RR 1.84), pneumonia (RR 1.66) and
physical or metabolic derangement (serous fluid and/or
electrolyte imbalance; RR 1.87; all at p<0.0001), as well
as gastrointestinal bleeding (RR 1.68; p<0.05), compared
with non-dementia patients. There was no signifi cant dif-
ference in the rates of sepsis, shock, surgical wound
infection, pulmonary failure or failure to rescue in
dementia patients compared with non-dementia
patients.
Compared with medical dementia patients, surgical
dementia patients had significantly higher RRs (at
p<0.05) of urinary tract infections (RR 1.09), pressure
ulcers (RR 1.24) and pneumonia (RR 1.42), but not of
delirium. In non-dementia patients, medical patients
were more likely than surgical patients to get a urinary
tract infection (RR 0.71; at p<0.0001); there were no
other significant differences. Dementia was consequently
a more informative indicator of risk of preventable com-
plications than was surgery for these four common com-
plications. Separately, while noting that dementia
patients were much less likely than non-dementia
patients to undergo surgery, the surgical procedures
carried out showed more risk of preventable complica-
tions for dementia patients than for non-dementia
patients.
The strongest findings of the study (at p<0.0001), with
the greatest differences in rates of dementia and non-
dementia patients, for surgical and medical cohorts,
were related to four common complications: urinary
tract infections, pressure ulcers, pneumonia and delir-
ium. Fourteen per cent of surgical dementia patients suf-
fered from urinary tract infections while in hospital,
which was 2.8 times higher than for surgical non-
dementia patients. Seven per cent suffered from pres-
sure ulcer, 1.84 times higher than for non-dementia
patients. Seven per cent also suffered from pneumonia,
1.66 times the rate for non-dementia patients and 5%
suffered delirium, which was 3.1 times higher than for
non-dementia patients. These infections and complica-
tions were not likely to be related to the person’s admit-
ted diagnosis; thus, they were more likely to be
nosocomial or hospital acquired and therefore poten-
tially preventable.
DISCUSSION
These findings demonstrate that hospitalised dementia
patients have higher rates of complications than hospita-
lised non-dementia patients, controlling for current
comorbidities, and that these rates of complications are
significantly higher in dementia patients who have
surgery. These findings support previous nationwide,
cohort designed Taiwanese findings that dementia
patients have higher rates of postoperative complications
than non-dementia patients at the hospital episode
level.
9
The highest rates and highest RRs for dementia
patients, for both medical and surgical patients, are for
urinary tract infections, pressure ulcers, delirium and
pneumonia. This new finding of high rates for four very
common preventable complications for dementia
patients offers avenues for intervention and prevention.
We note that, compared with hospitalised people who
do not have dementia, those with dementia are slightly
more likely to have multiepisode stays (87% vs 82%);
they are much more likely to be readmitted within
3 months of discharge (45% vs 32%) and average more
stays over the year (2.5 vs 1.9; calculations derived from
ref. 12). Having dementia may therefore bias estimates
of rates of preventable complications (primarily
upwards). However, sensitivity testing, not reported here,
indicated that, adjusting for sex, age and different pat-
terns of hospital stays, all comparisons that showed sig-
nificant differences in risk ratios for people with
dementia in our original analyses remained significant
in the adjusted analyses (and at the same p value level).
The effect of dementia on the likelihood of developing
avoidable complications was robust. Nevertheless, future
data collection planning should directly include infor-
mation about the number of episodes per stay, number
of rapid readmissions and number of stays per year.
Three key design features of this new Australian study
give additional credibility to the findings: (1) the com-
prehensive linked approach over 2 years of administra-
tive data to better identify dementia patients,
13
(2) the
patient-level risk-adjustment model to better capture
in-hospital complications
18
and (3) the inclusion of
50-year-olds to 65-year-olds with dementia who are
known to have different characteristics from other aged
populations.
5
Evidence is mounting for associations between poorer
nursing work environments and higher rates of patient
4
Bail K, Berry H, Grealish L, et al. BMJ Open 2013;3:e002770. doi:10.1136/bmjopen-2013-002770
Potentially preventable complications in hospitalised dementia patients
Table 2 Population, samples, percentage rates and relative risks of potentially preventable complications in the over 50 age group from NSW public hospital episode data 2006–2007
Preventable complication Patient population
Percentage of patient episodes with the
complication†
Relative risk of dementia patients with the complication compared
with non-dementia patients‡
Medical Surgical Medical Surgical
Sample Per cent Sample Per cent Sample RR (CI) Sample RR (CI)
Urinary tract infection Dementia 36 075 13.4 4854 14.7 58 223§ 1.79** (1.70 to 1.90) 7680 2.88** (2.45 to 3.40)
Non-dementia 146 813 7.9 18 986 5.6
All >50 182 888 9.0 23 840 7.4
Pressure ulcer Dementia 25 832 5.9 4007 7.3 38 480 1.61** (1.46 to 1.77) 5904 1.84** (1.46 to 1.31)
Non-dementia 89 074 3.8 13 493 4.1
All >50 114 906 4.2 17 500 4.9
Pneumonia Dementia 36 875 4.8 5106 6.8 59 523 1.37** (1.26 to 1.48) 8184 1.66** (1.36 to 2.02)
Non-dementia 150 118 3.5 20 497 4.2
All >50 186 993 3.8 25 603 4.7
Deep vein thrombosis Dementia 39 104 0.8 5154 1.4 62 459 0.82* (0.69 to 0.97) 8245 1.14 (0.78 to 1.68)
Non-dementia 155 882 1.0 20 609 1.2
All >50 194 986 0.9 25 763 1.2
Gastrointestinal bleeding Dementia 30 035 1.1 2702 3.8 50 246 1.01 (0.85 to 1.19) 5405 1.68* (1.22 to 2.31)
Non-dementia 131 088 1.1 16 215 2.3
All >50 161 123 1.1 18 917 2.5
Sepsis dementia 25 365 1.9 4469 10.6 39 218 1.34* (1.15 to 1.57) 6595 1.25 (0.96 to 1.64)
Non-dementia 94 631 1.4 15 100 3.1
All >50 119 996 1.6 19 569 4.9
Shock and cardiac arrest Dementia 31 021 0.6 2793 1.3 51 256 1.09 (0.86 to 1.37) 5521 0.93 (0.58 to 1.50)
Non-dementia 132 194 0.5 16 431 1.3
All >50 163 215 0.6 19 224 1.3
Delirium Dementia 37 933 4.0 5155 4.4 61 307 2.83** (2.54 to 3.15) 8251 3.10** (2.31 to 4.15)
Non-dementia 154 805 1.5 20 636 1.5
All >50 192 738 2.0 25 791 2.1
Surgical wound infection§ Dementia –– 5158 0.1 –– 8253 1.12 (0.48 to 2.63)
Non-dementia –– 20 633 0.0
All >50 –– 25 791 0.0
Pulmonary failure§ Dementia –– 2870 2.0 –– 5628 0.98 (0.81 to 1.19)
Non-dementia –– 16 660 1.7
All >50 –– 19 530 1.7
Physiological/metabolic
derangement§,¶
Dementia –– 2881 11.5 –– 5644 1.87** (1.55 to 2.25)
Non-dementia –– 16 699 6.5
All >50 –– 19 580 7.3
Failure to rescue†† Dementia 2597 28.2 561 22.3 3745 1.24* (1.02 to 1.33) 778 0.86 (0.61 to 1.20)
Non-dementia 8336 24.1 1647 25.0
All >50 10933 25.1 2208 24.3
*p<0.5.
**p<0.0001.
†Excluding precipitating pre-existing conditions for each complication.
‡Weighted 80–20% to compensate for 1 : 4 case–control ratio.
§These complications are only measured in a surgical population.
¶Physiological and/or metabolic derangement are serous fluid and electrolyte imbalances.
††Failure to rescue is death following sepsis, shock, gastrointestinal bleeding or pneumonia.
NSW, New South Wales; RR, relative risk.
Bail K, Berry H, Grealish L, et al. BMJ Open 2013;3:e002770. doi:10.1136/bmjopen-2013-002770 5
Potentially preventable complications in hospitalised dementia patients
Table 3 Evidence of association between the four key complications and nursing work environments
Study Sample
Location and data
time frame
Characteristics of nursing work environments
(independent variable)
Patient complication
(dependent variable)
Cimiotti
22
161 hospitals
1 571 068 patients
7076 nurses
USA 2006 Lower levels of burnt out (a) nurses Lower rates of urinary tract infection
Needleman et al
18
799 hospitals
6 million+ patients
USA 1997 Higher levels of total nurse staffing Lower rates of urinary tract infection
Cho et al
23
232 hospitals
124 204 patients
USA 1997 Higher proportions of RNs (b) Lower rates of pneumonia
Kovner et al
24
187 hospitals USA 1990–1996 Higher RN hours per patient day Lower rates of pneumonia
Pappas et al
25
2 hospitals
3200 patients
USA 2007 Higher RN hours per patient day Lower rates of pneumonia
Kane et al
11
Systematic review
96 studies
USA 2006 Higher proportions of RN per patient day Decreased OR of hospital-acquired
pneumonia
Twigg et al
26
3 hospitals
236 454 patients
150 925 nurses
Australia 2000–2004 Refined staffing model (c) Lower rates of pneumonia Lower rates
of delirium
Schubert et al
27
8 hospitals
779 patients
1338 nurses
Switzerland 2003–2004 Implicit care rationing (d) Predicted higher levels of pressure
ulcers
Horn et al
28
82 RACF
1376 residents
USA 1996–1997 Higher RN direct time per resident per day Lower rates of pressure ulcers
Pekkarinen et al
29
66 RACF
724 nurses
Finland 2002 Increased time unit pressure (e) Higher rates of pressure ulcers
Hickey et al
30
35 RACF
Patient assessment
files
Staffing data
USA 1998–1999 Lower skill mix (less RNs) Higher rates of pressure ulcers
(a) Burnt out: where workers emotionally and cognitively detach from work as a way to cope with demands.
(b) RN: registered nurse—a graduate from a University or college nursing programme who has met national licensing conditions.
(c) Refined staffing model: which developed categories of nurse staffing based on patient complexity, intervention levels, high dependency beds, emergency/elective patient mix and patient
turnover.
(d) Implicit care rationing: where nurses withhold or fail to carry out necessary nursing tasks due to inadequate time, staffing level and/or skill mix.
(e) Time unit pressure: as a measure of nursing working conditions.
RACF, residential aged care facility.
6 Bail K, Berry H, Grealish L, et al. BMJ Open 2013;3:e002770. doi:10.1136/bmjopen-2013-002770
Potentially preventable complications in hospitalised dementia patients
complications (see table 3) and demonstrates that, for
the four key complications found for dementia patients
in the present study, these complications may be modifi-
able. Nursing interventions, with and without direct
medical personnel involvement, for preventing or miti-
gating these common complications involve mobility,
hydration, hygiene, patient education and reassurance
in a context of nursing surveillance, assessment, early
intervention and advocacy. Nurses, more than any other
healthcare professional, are able to recognise, interrupt,
evaluate and correct healthcare errors.
31
Specifically, in
relation to urinar y tract infections, it is argued that
higher levels of engaged and educated nurses better
enable sterile techniques for catheter insertion, time-
consuming toiletin g programmes and management of
hygiene and hydration.
20 32
In relation to pneumonia,
nurses are responsible for (or at least instrumental in)
many of the necessary clinical practices, such as encour-
aging flu vaccination, hand washing, pain relief, mobil-
isation and pulmonary hygiene for reducing
pneumonia.
32
In relation to delirium, simple preventa-
tive measures, such as verbal reorientation, correcting
sensory deficits, improving mobilisation, improving
hydration, decreased use of sleeping and psychoactive
medications and restraints,
33
are initiated, maintained
and reinforced by nurses in acute settings. In relation to
pressure areas, patient positioning and skin care are the
primary domain of nurses more than any other profes-
sion, and their actions in relation to hydration, nutrition,
mobility and pain relief are also accepted as having a sig-
nificant impact on the prevention of pressure ulcers.
34
The development of complications can be set in motion
by a seemingly innocuous first event (eg, a urinary tract
infection can develop from dehydration, which can start
with something as simple as a missed cup of morning
tea). This has been termed ‘cascade iatrogenesis’ and is
a helpful concept in understanding the link between
unmet nursing care needs and potentially preventable
complications.
35 36
These findings highlight the need to view nursing as
an intervention rather than as a labour cost in terms of
the nursing work environment’s impact on patient out-
comes. Despite hospitals spending approximately
one-third of their budget on ward nursing,
37
“adminis-
trative datasets have not been designed to capture a
great deal of information about nurses.”
32
Staffing data
in Australia are limited to hospital level aggregate data
for a whole year, without differentiation of types of
nurses (eg, registered nurse or unlicensed personnel),
or state level data by the nurse’s postcode of residence.
Better hospital nursing data would enable research
investigating associations between nurse staffing and
patient outcomes, as well as opportunities for systemic
benchmarking.
938
The USA has a more systemic
approach to data collection in relation to nursing care
but many of the data items are restricted to specific loca-
tions (eg, intensive care units). Recommendations have
been made that the minimum datasets in America be
expanded so that urinary tract infections and pneumo-
nia are measured in all at-risk hospitalised patients.
32
The present study would support this policy. We would
also suggest that future acute dementia care intervention
studies consider controlling for relevant nursing
characteristics.
The four key complications identifi ed here have some
of the highest dollar costs for hospitals. For example,
though urinary tract infections and pneumonia have
relatively low per-case costs, their large volume means
that they have the greatest system financial impact in
Australia.
3
If we want to reduce the cost and occurrence
of preventable complications in hospitalised dementia
patients, we need to better understand the relationships
between nursing work environments and patient out-
comes. In order to increase this understanding, we need
better data collection strategies for quality benchmark-
ing and research. These data collection strategies need
to include (1) screening and documentation of demen-
tia patients in hospital, (2) minimum nursing work
environment characteristics, such as appropriate ratios
of registered nurse staffing and skill mix and manage-
ment of workload/pressure and burnout/retention, and
(3) rates of the common in-hospital complications of
urinary tract infections, pressure ulcers, pneumonia and
delirium, and not just as secondary diagnoses.
CONCLUSION
Dementia patients have higher rates of potentially pre-
ventable complications while in hospital than do non-
dementia patient s, even when controlling for age, sex,
surgery and comorbidities. The highest rates and largest
differences in rates, for dementia patients compared with
non-dementia patients, are seen in urinary tract infec-
tions, pneumonia, pressure ulcers and delirium. These
complications have been specifically associated with
aspects of nursing work environments, including staffing
skill mix of registered nurses, and workload measures,
such as burnout and time pressure. Modifying aspects of
the nursing work environment may reduce or prevent
these complications in hospitalised dementia patients
(and, indeed, in other patients). Improving hospital data
collection strategies for the identification of dementia
patients and key nursing characteristics would enable
benchmarking and research in order to improve the
care, and cost of care, for this burgeoning population.
Author affiliations
1
Faculty of Health, University of Canberra, Canberra, Australian Capital
Territory, Australia
2
Centre for Research and Action in Public Health, The University of Canberra,
Canberra, Australian Capital Territory, Australia
3
University of New South Wales, Academic Department for Old Age
Psychiatry, Euroa Centre, Prince of Wales Hospital, Randwick, New South
Wales, Australia
4
Data Linkage Unit, Australian Institute of Health and Welfare, Canberra,
Australian Capital Territory, Australia
5
Ageing and Aged Care, Australian Institute of Health and Welfare, Canberra,
Australian Capital Territory, Australia
Bail K, Berry H, Grealish L, et al. BMJ Open 2013;3:e002770. doi:10.1136/bmjopen-2013-002770
7
Potentially preventable complications in hospitalised dementia patients
Contributors DG, BD, RK and AP devised the idea of the Hospital Dementia
Services study, designed the methods, raised the funding and conducted the
analysis. KB was responsible for implementing the nested study reported here
and carrying out all the analyses. HB and LG supervised this nested study.
HB, RK and BD provided statistical advice. KB prepared the first draft of the
manuscript and all authors contributed to each section of the final draft of the
manuscript. KB is guarantor.
Funding The Hospital Dementia Services Project was funded by the National
Health and Medical Research Council (ID465701). DCRC provided a PhD
scholarship to the first author.
Competing interests All authors have completed the Unified Competing
Interests form at http://www.icmje.org/coi_disclosure.pdf (available on request
from the corresponding author) and declare: KB was supported by a PhD
Scholarship funded by the Dementia Collaborative Research Centre—
Assessment and Better Care, University of New South Wales as part of an
Australian Government Initiative. Support has been received by the employing
organisations from Alzheimer’s Australia in regard to commissioned work
using data collected in the course of the Hospital Dementia Services Project.
No other declarations are made regarding other relationships or activities that
could appear to have influenced the submitted work.
Ethics approval Obtained from the NSW Population and Health Services
Research Ethics Committee (HREC/08/CIPHS/49 and 2008/11/109), the Australian
Institute of Health and Welfare Ethics Committee, the University of NSW and the
University of Canberra Human Research Ethics Committees (08–85).
Provenance and peer review Not commissioned; externally peer reviewed.
Data sharing statement Statistical code and technical appendix available
from the corresponding author. Dataset inquiries can be made to the
Australian Institute of Health and Welfare via the corresponding author.
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