Health status and quality of life before critical illness: Northern Finland Birth Cohort 1966 study.

Background: Previous findings support the claim intensive care unit (ICU) patients have a higher rate of comorbidities and reduction of health- and functional status compared with the normal population.

Aim: In this prospective observational study, our aim was to determine those health-related factors at the age of 31 years which were associated with a later critical illness among previously un-hospitalized individuals by exploring data obtained from the Northern Finland Birth Cohort 1966 (NFBC1966).

Methods: NFBC1966 is a Finnish birth cohort, which includes 12,058 live births with expected dates of delivery during 1966. The study was conducted among cohort participants who had not been hospitalized for any reason before the cohort follow-up visit at the age of 31. The study group included NFBC1966 participants who were admitted to the ICU of the Oulu University Hospital. The control group included participants who were treated for any reason in regular hospital wards. The data considering the participants' health status and behavior at the age of 31 were collected from the NFBC1966 database. The gathering of ICU and hospitalization data was concluded on December 31, 2016.

Results: 849 NFBC1966 participants met the inclusion criteria: 69 were treated in the ICU (study group) and 780 on regular hospital wards (controls). In the study group, the rate of neurological diseases (26% vs. 16%, 95% CI: -21.8%, -0.2%), malignancy (3% vs. 0.7%, 95% CI: -9.7%, 0.0%), alcohol abuse (4.5% vs. 1%, 95% CI: -11.5%, -0.3%) and smoking (77% vs. 65%, 95% CI: -21.6%, -0.3%) were higher compared with the control group. The patients in the ICU group were also more prone to violent injuries, (17% vs. 7%, 95% CI: -20.2%, -1.9%), practiced less hard physical activity (65% vs. 78%, 95% CI: 2.1%, 25.3%) and had lower maximal muscle strength according to the hand grip test (30 vs. 34 kg, 95% CI: -8.2, 8.6 kg).

Conclusions: In this study examining previously un-hospitalized patients, the main factors associated with future critical illness were neurological comorbidities, malignancy, alcohol misuse, smoking, low maximum muscle strength, and less frequent physical exercise compared with those with hospitalization not requiring ICU admission.