Social support: a significant factor for health-related quality of life after critical illness?

Introduction

Decreased health-related quality of life (HRQoL) is well known for the previous ICU population after critical care, and many factors are of importance for this outcome. We have in a recent study shown that pre-existing disease is most important. This finding was made when comparing a control population adjusting for co-morbidities and approximately 50% of the decrease in HRQoL was attributed to co-morbidities. Therefore, there must be other factors that contribute to the HRQoL decrease. In HRQoL research it has been shown that social support also is important for the HRQoL experience. In the southeast of Sweden, two neighbouring large cities are known to have different social support patterns depending on their differences in social structure. We hypothesized that the social support is different between the patients coming from city A's ICU compared with city B. The aim of this study was to examine to what extent social support affected HRQoL outcome in the follow-up of these patients in general and to what extent it differed between the patients of ICUs of the different cities.

Methods

Mixed ICUs from two hospitals in different cities. Questionnaires, including the social support instrument Availability of Social Integration (AVSI), the HRQoL scale SF-36, demographic data and previous illnesses, were sent 6 months after discharge to all adult patients.

Results

Six hundred and thirty-three (57%) patients returned the questionnaire, 371 from city A. The ICU patients from city B reported a significantly lower mean score in social support compared with city A, 18.3 (SD 6.3) compared with 19.6 (SD 6.5) (P = 0.013). The SF-36 scores in all subscales showed no significant differences between the two cities. The results demonstrate that ICU patients with pre-existing disease have eight times higher risk of a decreased physical component score, and nearly six times higher risk of a decreased mental component score than the previously healthy patients. ICU patients with lower mean social support scores had 0.16 higher risks of a decreased physical score and 0.46 higher risks of a decreased mental component score.

Conclusions

This study indicates that social support has a significant, but small, effect on HRQoL in former ICU patients. Importantly, the magnitude of this effect was too small to be relevant in comparisons of HRQoL in former ICU patients from cities with different social structures within one country.