Psychosocial risk factors for hospital
readmission among community based
adults with COPD: a prospective study
Peter A Coventry, Islay Gemmell,
Chris Todd
University of Manchester, UK
Burden of chronic obstructive pulmonary disease
(COPD)
• The global prevalence of COPD in adults aged ≥40
years is 10% and increasing
• In 2000, an estimated 10 million US adults reported
physician-diagnosed COPD but under-diagnosed
• Major burden on healthcare systems:
• 8 million physician office and hospital outpatient visits
• 1.5 million emergency department visits
• 726,000 hospital admissions
Cost of COPD
•
NHLBI survey estimated the total cost of COPD to the US in 2005
was $38.8 billion
• $21.8 billion in direct costs
• about 70% for hospital admissions and inpatient care
• 10% of COPD patients responsible for over 70% of total expenditure
•
In UK NICE estimates that the direct cost of care in the NHS is £500
million a year
•
One in eight (130,000) emergency medical admissions in adults is
due to COPD
• largest cause of emergency admission in the UK
• over 80% of the direct costs due to the high number of bed days
Impact of hospital admission
• In-patient mortality is about 10% and within 12-months it
is about 40%
• Rapid readmission for acute exacerbation within 3months occurs in about 30% patients
• Readmission within 12-months in up to 55% patients
• Impaired health related quality of life and increased
psychosocial morbidity
• A meta-analysis of 13 studies (n=900) found that the
prevalence of depression was 40% (95% CI: 36 to 44%),
and 36% for anxiety (95% CI: 31 to 46%)
Risk factors for readmission
• Physiological factors, medication history and health
status associated with risk of readmission
• Despite high prevalence we know relatively little about
impact of anxiety and depression on hospital
(re)admissions
• Psychosocial factors are associated with
– impaired health status (lower QOL)
– poorer treatment outcomes and reduced survival
following emergency treatment
– longer hospitalisation
– poorer prognosis within 12-months after hospital
discharge
Aims of the study
• Are psychosocial factors associated with risk of
readmission in community based COPD patients?
• We hypothesised that psychosocial factors will be
significantly associated with readmission regardless of
disease severity and other covariates (age, gender etc)
• Measure change in psychosocial status over 12 months
after index admission
Methods (1): design and sampling
• Prospective cohort study with follow-up at 90 and 365
days
• Validated diagnosis of COPD (ICD−10 codes J40−J44,
J47)
– clinical history
– FEV1/FVC ratio 70% and FEV1 <80% predicted
• Exclusion criteria:
– cancer or other terminal illness
– other obstructive airways disease (bronchiectasis,
asthma) or lung reduction surgery
– severe and enduring mental health problems
Methods (2): data collection
• Primary outcome is readmission/death following index
admission during observational period
• Recruited patients admitted for exacerbation at home 1
week after discharge from 3 acute NHS hospitals in UK
• Routine data collected at baseline:
– sociodemographics
– lung function (FEV1 % predicted)
– previous hospital admission for COPD
– medication history
– medical comorbidities
• Self-report tools used to measure psychosocial status
Methods (3): measuring QOL and psychological
morbidity
• HRQOL measured with St George’s Respiratory
Questionnaire (SGRQ)
– total score (0-100; higher scores indicate poorer QOL;
difference of 4% is clinically significant)
• Hospital Anxiety and Depression Scale (HADS)
– validated and reliable psychological screening
instrument used in medically ill populations
– 14-item self-report questionnaire with two 7-item
subscales for anxiety and depression
– scores range from 0 to 21
– scores of ≥8 on either sub-scale used as cut-off for
caseness
Methods (4): measuring social support
•
Emotional support central to ‘buffering’ model of social support
– support is beneficial in times of crisis or stress
– support reduces impact of stressor by assisting coping strategies
•
Enhancing Recovery in Coronary Heart Disease (ENRICHD) trial
developed tool to measure social support (ENRICHD Social Support
Instrument [ESSI])
•
ESSI is a 7 item scale measuring deficiencies in perceived
instrumental, structural and emotional support
– score of 3 or less on 2 or more items, excluding items about help with
chores and marital status, and/or a total score of ≤18 on remaining
items defines low social support.
•
First time it has been used in a COPD population
Analysis
• Univariable logistic regression analysis was used to
assess which psychosocial variables were associated
with readmission at 90 days
• Multivariable logistic regression adjusted for age and
gender and % predicted FEV1 were used to estimate
which psychosocial variables were independently
associated with readmission at 90 days
Results (1): descriptive statistics
Sample characteristics at baseline
Mean age (SD)
Sex, male n (%)
FEV1% predicted, mean (SD)
SGRQ total, mean (SD)
n=79
65.3 (9.9)
44 (56)
42.2% (18.4)
58.8 (14.6)
HADS anxiety, mean (SD)
8.7 (4.2)
HADS depression, mean (SD)
7.0 (3.7)
HADS total, mean (SD)
15.7 (6.9)
ESSI total, mean (SD)
26.5 (6.3)
Results (2)
• High levels of psychological distress
– 46 (58.2%) HADS – anxiety ≥8
– 34 (43%) HADS – depression ≥8
• But high levels of emotional support
– 25% patients had low social support
• 26 (32.9%) patients were readmitted within 90 days
• Univariable logistic regression :
– FEV1% predicted significant predictor of readmission (OR=0.97;
95% CI:0.94, 1.00, p=0.033)
• Multivariable logistic regression:
– QOL, adjusted for age, gender and FEV1% predicted was
significant predictor (OR=1.04; 95% CI:1.00, 1.09, p=0.049)
Conclusions and limitations
• Lung function, HRQOL, age and gender appear to be
key drivers of rapid hospital readmission
• Anxiety and depression not risk factors for readmission
• Social support does not seem to have an impact on risk
of readmission – does it act as a buffer?
• Small sample size and insufficient power to detect a
significant difference in psychosocial status between
patients who are readmitted and not readmitted
• Future analysis to examine if change in scores for
psychosocial variables is associated with readmission
after 90 days
Implications for policy and practice
• Further work to investigate if psychosocial factors are
linked to coping and potentially modifiable:
– improved self-management
– reduced demand on health services
• Community based pulmonary rehabilitation programmes
that include psychosocial support improve
–
–
–
–
exercise capacity
HRQOL,
anxiety and depression
and possibly reduce admissions