Changes in health-related quality of life from 6 months to 2 years after discharge from intensive care

Kvåle Reidar, Flaatten, Flaatten Hans

Description

Intensive care patients have, both before and after the ICU stay, a health-related quality of life (HRQOL) that differs from that of the normal population. Studies have described changes in HRQOL in the period from before the ICU stay and up to 12 months after. The aim of this study was to investigate possible longitudinal changes in HRQOL in adult patients (>18 years) from 6 months to 2 years after discharge from a general, mixed intensive care unit (ICU) in a university hospital. Methods This is a prospective cohort study. Follow-up patients were found using the ICU database and the Peoples Registry. HRQOL was measured with the Short Form 36 (SF-36) questionnaire. Answers at 6 months and 2 years were compared for all patients, surgical and medical patients, and different admission cohorts. Differences are presented with 95% confidence intervals. The SF-36 data were scored according to designed equations. SPSS 11.0 was used to perform t-tests and Mann-Whitney tests. Results A total of 100 patients (26 medical and 74 surgical) answered the SF-36 after 6 months and again after 2 years. There was overall moderate improvement in 6 out of 8 dimensions of the SF-36, and the average increase in score was + 4.0 for all 8 dimensions. The changes for surgical and medical patients were similar. Neurological and respiratory patients reported increased average HRQOL scores, while cardiovascular patients did not. Patients with worsening of scores from 6 months to 2 years were insignificantly older than patients with improved scores (55.3 vs. 49.7 years), and both groups had comparable severity scores (simplified acute physiology score, SAPS II, 37.2 vs. 36.3) and length of ICU stay (2.7 vs. 3.2 days). The statistically significant changes in HRQOL (in the Role Physical and Social Functioning dimensions) were, due to sample size, barely clinically relevant. Conclusion In a mixed ICU population we found moderate increases in HRQOL both for medical and surgical patients from 6 months to 2 years after ICU discharge, but the sample size is a limitation in this study.

Informations

• Publié par: biomed
• Publié le: 01 janvier 2003
• Nombre de lectures: 1
• Langue: English

Extrait

Health and Quality of Life Outcomes
BioMed Central
Open AccessResearch
Changes in health-related quality of life from 6 months to 2 years
after discharge from intensive care
Reidar Kvale* and Hans Flaatten
Address: Department of Anaesthesia and Intensive Care, Haukeland University Hospital, N-5021 Bergen, Norway
Email: Reidar Kvale* - [e-mail]; Hans Flaatten - [e-mail]
* Corresponding author
Published: 24 March 2003 Received: 28 February 2003
Accepted: 24 March 2003
Health and Quality of Life Outcomes 2003, 1:2
This article is available from: http://www.hqlo.com/content/1/1/2
© 2003 Kvale and Flaatten; licensee BioMed Central Ltd. This is an Open Access article: verbatim copying and redistribution of this article are permitted in
all media for any purpose, provided this notice is preserved along with the article's original URL.
Abstract
Background: Intensive care patients have, both before and after the ICU stay, a health-related
quality of life (HRQOL) that differs from that of the normal population. Studies have described
changes in HRQOL in the period from before the ICU stay and up to 12 months after. The aim of
this study was to investigate possible longitudinal changes in HRQOL in adult patients (>18 years)
from 6 months to 2 years after discharge from a general, mixed intensive care unit (ICU) in a
university hospital.
Methods: This is a prospective cohort study. Follow-up patients were found using the ICU
database and the Peoples Registry. HRQOL was measured with the Short Form 36 (SF-36)
questionnaire. Answers at 6 months and 2 years were compared for all patients, surgical and
medical patients, and different admission cohorts.
Differences are presented with 95% confidence intervals. The SF-36 data were scored according
to designed equations. SPSS 11.0 was used to perform t-tests and Mann-Whitney tests.
Results: A total of 100 patients (26 medical and 74 surgical) answered the SF-36 after 6 months
and again after 2 years. There was overall moderate improvement in 6 out of 8 dimensions of the
SF-36, and the average increase in score was + 4.0 for all 8 dimensions. The changes for surgical
and medical patients were similar. Neurological and respiratory patients reported increased
average HRQOL scores, while cardiovascular patients did not. Patients with worsening of scores
from 6 months to 2 years were insignificantly older than patients with improved scores (55.3 vs.
49.7 years), and both groups had comparable severity scores (simplified acute physiology score,
SAPS II, 37.2 vs. 36.3) and length of ICU stay (2.7 vs. 3.2 days). The statistically significant changes
in HRQOL (in the Role Physical and Social Functioning dimensions) were, due to sample size, barely
clinically relevant.
Conclusion: In a mixed ICU population we found moderate increases in HRQOL both for medical
and surgical patients from 6 months to 2 years after ICU discharge, but the sample size is a
limitation in this study.
Background but from that time further survival is comparable [1–3].
Intensive care patients have a higher mortality than the Health-related quality of life (HRQOL) is an important
normal population up to 1–2 years after ICU discharge, outcome measure after intensive care. A number of
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questionnaires have been introduced to investigate HR- The SF-36 is a generic, self-administered general health
QOL [4,5]. Results are found to be influenced by diagno- status survey with 36 questions aggregated into 8 do-
sis, severity of illness, age and pre-morbid health status mains/dimensions: General health (GH), Physical Func-
[6,7]. Quality of life studies are often difficult to compare, tioning (PF), Role Physical (RP), Role Emotional (RE),
since different intensive care populations have been stud- Social Functioning (SF), Bodily Pain (BP), Vitality (VT)
ied and a variety of quality of life measures have been and Mental Health (MH). Each is scored from 0 (worst
used, at different times after ICU discharge. In addition, score) to 100 (best score). It has been tested and found
the practice of intensive care varies [8]. both valid and reliable in the ICU setting [21], and is one
of the recommended outcome measures [5]. The SF-36
In general post-ICU HRQOL is found to be markedly re- has also been found to be stable over time [22].
duced compared with population scores [9–14]. Several
studies have found changes in HRQOL from before ICU SF-36 scores after 6 months were compared with scores af-
and up to 6 or 12 months after, with worsening for pa- ter 2 years for a) all patients, b) medical patients, c) surgi-
tients suffering acute pathologies (i.e. predominantly sur- cal patients and d) the 3 largest admission categories
gical patients) and improvement or no change for patients (neurological, respiratory and cardiovascular). We also
with pre-existing ill health (i.e. predominantly medical compared the SF-36 scores after 6 months for the 26 pa-
patients) [6,7,15–18]. tients who answered only once with the 100 patients who
answered again after 2 years.
It has been suggested that follow-up after ICU discharge
should last until further survival match population surviv- There is no overall SF-36 score, but Mental Component
al (after 2 years) and that simultaneous longitudinal Summary (MCS) and Physical Component Summary
changes in HRQOL can be a measure of effectiveness of re- (PCS) have been used [13,23]. In this study we chose to
habilitation and rate of recovery [19]. Few such studies summarize the 8 dimension scores for each patient after 6
have been performed. The aim of this study was to use the months and compare the sum with the individual sums
Short Form 36 (SF-36) [20] questionnaire to investigate after 2 years, thus dividing patients into one group with
possible longitudinal changes in HRQOL from 6 months unchanged or reduced "total score" and another with in-
to 2 years after ICU discharge in a general, mixed ICU creased "total score". These 2 groups were compared, as
population. Our hypothesis was that average HRQOL were medical and surgical patients, to see if there were dif-
would improve from 6 months to 2 years after discharge. ferences with respect to age, severity of illness (SAPS II),
length of ICU stay (LOS) and intermittent positive pres-
Methods sure ventilation (IPPV) times. All age data refer to age at
Haukeland University Hospital is a 1000-bed tertiary re- ICU admission.
ferral hospital for 900 000 inhabitants in Western Nor-
way. The 10-bed mixed ICU is predominantly surgical The study was approved by the regional ethical
(70% of admissions). Heart surgery patients, neonates committee.
and burn patients are treated in specialized units outside
the ICU. All ICU admissions are recorded in a database. Statistical methods
Approximately 360 patients are admitted annually, with Continuous and discrete data (when appropriate) are giv-
en as mean values with standard deviations (SD) and me-an average age of 49.5 years and an average ICU length of
stay (LOS) of 5.0 days. Hospital mortality from 1997 to dian values with range. Differences between groups are
2001 has been in the range of 28% to 32%. The main rea- presented with the corresponding 95% confidence inter-
son for ICU admission is chosen from 8 categories: neuro- vals. The SF-36 data were collected in a FileMaker 5.0 da-
logical, respiratory, cardiovascular, gastrointestinal, tabase and automatically scored using previously
postoperative, renal failure, trauma and miscellaneous. published equations [24]. SPSS 11.0 was used to perform
SAPS II is used for severity scoring. t-tests and paired t-tests for SF-36 scores. The results were
controlled with Wilcoxon signed rank sum test. The
Adults (>18 years) with an ICU stay of more than 24 Mann-Whitney test was used for skewed continuous data.
hours who were discharged between July 1999 and August
2000 were eligible to enter this prospective study. The Results
Peoples Registry of Norway (Folkeregisteret) was used to Included patients
identify survivors 6 months after ICU discharge. These In the study period a total of 226 patients above 18 years
were sent the SF-36 questionnaire with an information and with an ICU stay of more than 24 hours were dis-
letter. The responders were sent the questionnaire again charged alive from the ICU. Four were in the ICU for pure
two years after ICU discharge. Non-responders received observational reasons, 31 died within 6 months after ICU
one reminder. discharge, 9 were lost to follow-up, 126 answered the SF-
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SF-36 answers
6 months after
ICU discharge
n = 126
SF-36 answers Died between No answer Lost to 2-year
2 years after ICU 6 months and after 2 years follow-up
discharge 2 years n = 11 (moved abroad)
n = 100 n = 14 n = 1
Figure 1
Follow-up status at 2 years for the 126 patients answering the SF-36 at 6 months after ICU discharge.
36 questionnaire and 56 did not answer. Two years after The distribution of individual changes in summarized SF-
ICU discharge, another 14 patients of the 126 responders 36 scores was close to the Normal distribution, with 92%
had died, one had moved abr