Need for intensive care in patients admitted for asthma: Red flags from the social history

Asthma deaths in Australia are associated with illicit substance abuse, mental health problems and social issues. However, a large proportion of these deaths occurs out of hospital and is difficult to avert by the time the individuals seek medical attention. We hypothesized that these characteristics may also increase the risk for a patient to require intensive care admission when they present to emergency departments.

We studied consecutive patients admitted to a tertiary metropolitan hospital with a primary diagnosis of asthma between January 2010 and January 2014. Clinical and demographical data were obtained from chart review. The patient's postcode was used as a surrogate for socioeconomic status.

There were 482 asthma patients admitted during the study period, of which 39 required intensive care. Ten patients admitted to intensive care (26%) used illicit drugs compared with 29 (7%) of those admitted to the ward (adjusted odds ratio: 3.6, P = 0.012). For illicit users, nonadherence to preventer therapy was associated with an even higher risk of intensive care unit admission. Socioeconomic index was lower in the group requiring intensive care admission. The frequency of psychiatric diagnoses was similar in both groups.

Among patients admitted to hospital for asthma, illicit substance abuse is a strong independent risk factor for intensive care requirement. Preventer therapy nonadherence further increases this risk. Lower socioeconomic status is also associated with increased risk. These historical features should be actively sought on admission and may serve as useful 'red flags' to prompt consideration of intensive monitoring.