Aim
The aim was to determine factors that influence post-ICU psychological distress in family members. We hypothesized that family members with higher levels of satisfaction with ICU care would have lower levels of psychological distress following their close others’ ICU stay. We further hypothesized that family members who were female, lived further away, had lower education levels, were spouses / partners, co-habited, and whose critically ill family member was of a younger age and stayed longer or died in ICU would exhibit higher levels of post-ICU psychological distress.
Design
We conducted a prospective, single-centre observational study. Data were collected from March 2018 to July 2019 using a written questionnaire with several well-validated self-report measures and by extracting data from clinical records.
Setting, Participants, and Procedures
The study took place in one surgical-transplant ICU in a 900-bed Swiss University Hospital. Participants were family members of adult persons cared for in ICU for 24 hour or longer. Family members were defined as close others from the patient’s perspective or as noted in the clinical record. They had to be 18 years of age and able to fill in the German language questionnaire. No other exclusion criteria were identified.
We used a consecutive sampling strategy. Potential participants were identified from the clinical record. Family members meeting the inclusion criteria received the study information pack together with a written questionnaire by mail after their close other had been discharged from ICU. After a first phase of data collection (March – September 2018) a nurse-led family support service was introduced on the unit. Subsequently, only those family members who received the service in addition to meeting the inclusion criteria were invited to take part (October 2019 – July 2019). Return of the completed written or online questionnaire (https://www.project-redcap.org/) was taken as informed consent. A research assistant followed family members up or sent out written reminders after four and eight weeks if necessary.
Measures
Independent variables
To assess families’ satisfaction with intensive care, the validated, 24-item German version of the Family Satisfaction in the ICU (FS-ICU-24) was used (25, 26). The FS-ICU-24 assesses on a 5-point-Likert scale the satisfaction with care and with involvement in decision-making. A standardized score of 0-100 is calculated, whereas 100 indicates maximal satisfaction. The FS-ICU-24 has excellent psychometric properties (27), with a high internal consistency (Cronbach’s alpha of > 0.90) (25, 26), also in our sample.
A brief demographic form was used to obtain patient- andfamily member-related characteristics, including family members’ age, gender, educational level, living situation, type of relationship to patient, and distance to hospital. Questions about patient age, gender, and reason of ICU admission were also included in the demographic form. Information on length of stay and death were extracted from the clinical record.
Dependent variables
In accordance with definitions of PICS-F (13), we assessed depression, anxiety, and posttraumatic stress. We used the recommended (11, 12, 14) and well-validated German version of the Hospital Anxiety and Depression Scale (HADS) (28, 29). The HADS rates on a 4-point Likert scale anxiety (HADS-A, 7 item, score 0-21) and depression (HADS-D, 7 items, score 0-21), where higher scores indicate worse symptoms. A value of eight or higher has been reported to be indicative of mild depression or anxiety (29, 30), and one of 10 or higher for severe depression or anxiety (11-13). Cronbach’s alpha of the German version is above .80 for both subscales (28). In our sample, it was .86 and .88.
To measure stress, we used the 6-item short form of the German version of the Impact of Event Scale-Revised (IES-R-6) (31, 32). The IES-R-6 measures severity of subjective stress on a 5-point Likert scale (score from 0-24), with a high score indicating posttraumatic stress. The IES-R-6 is a valid measure (Cronbach’s alpha = .80) that correlates highly with the 22-item IES-R. Cronbach’s alpha in our sample was satisfactory with .75. A value of over 30 is used in the IES-R-22 item version whose score ranges from 0-88, which corresponds with a cut-off value of nine with the shorter six-item version used in our study.
Data analysis
Data analysis was performed using R version 3.6.1 (33). The outcomes depression, anxiety (HADS subscales) and posttraumatic stress (IES-R-6) were analyzed by linear mixed-effects models with a random intercept per patient to account for the dependence of family members from the same patient. Family satisfaction with care (FS-ICU-24), the family member characteristics of age, gender, relationship type (spouse / partner vs. other), co-habitation (yes vs. no), educational level (tertiary / university vs. other), distance to hospital (same region vs. other) and the patient characteristics age, gender, cause of ICU admission (unplanned admission is used as reference category), length of ICU stay (> 5 days vs. ≤ 5 days), and death were used as explanatory variables in the model. Because one third of participants (n=75) took part in the study after a new family support service was introduced, receiving the nurse-led family support service (yes vs. no) was also included as an explanatory variable in the model.
Ethical approval
The study was reviewed by the Ethics Committee of the Canton of Zurich, which waived the need for approval (Req-2018-00107). We followed national guidelines of Research with Humans (34).