Factors associated with anxiety in critically ill patients: A prospective observational cohort study

Anxiety is an unpleasant emotion that most intensive care patients experience. This emotion is an important issue in intensive care settings because of its prevalence, adverse effects and severity. Little is known about the factors associated with state and trait anxiety during critical illness.

To describe the patterns of state anxiety reported by intensive care patients, and identify factors associated with state and trait anxiety.

Prospective observational cohort study.

One mixed intensive care unit in Brisbane, Australia.

Adults (n=141, ≥18 years) admitted to the intensive care unit for ≥24h; able to communicate verbally or non-verbally; understand English; and, open their eyes spontaneously or in response to voice.

Outcomes were state anxiety as measured by the Faces Anxiety Scale and trait anxiety as measured by the State-Trait Anxiety Inventory. Pre-intensive care factors tested for possible associations with both state and trait anxiety were: age, gender, marital status, employment status, level of education, smoking status, personality trait of optimism and evidence of mental health care/treatment. Intra-intensive care factors tested were: reason for admission to the intensive care unit, delirium, pain, airway status, hours of mechanical ventilation, severity of illness, days of stay in intensive care, exposure to corticosteroids, opioids, benzodiazepines, anxiolytics, antidepressants, beta-blockers, anaesthetic agents and analgesics; length of sedation and analgesia and total doses of sedatives and analgesics.

Of 141 participants, 98 (70%) were male with an average age of 54 (standard deviation: ±15) years and stayed in intensive care for about 4 (Interquartile Range: 3-7) days. The majority (n=115; 82%) of participants experienced state anxiety at least once during their stay in intensive care, with 57% reporting moderate to severe levels. Factors related to state anxiety in intensive care were pain and trait anxiety. Factors associated with trait anxiety were trait optimism, state anxiety, evidence of mental health care/treatment and age.

This study provides a better understanding of contributing factors for anxiety in the critically ill. Trait anxiety and state anxiety were significantly associated with each other, namely, patients who were anxious by nature experienced higher levels of state anxiety, which persisted throughout their stay in the intensive care unit. Recognising the importance of state and trait anxiety assessments using validated tools and determining ways to manage anxiety in the critically ill are critical aspects of the intensive care nurses role.