The prevalence of nonadherence in difficult asthma

Am J Respir Crit Care Med. 2009 Nov 1;180(9):817-22. doi: 10.1164/rccm.200902-0166OC. Epub 2009 Jul 30.


Rationale: With the advent of new and expensive therapies for severe refractory asthma, targeting the appropriate patients is important. An important issue is identifying nonadherence with current therapies. The extent of nonadherence in a population with difficult asthma has not been previously reported.

Objectives: To examine the prevalence of nonadherence to corticosteroid medication in a population with difficult asthma referred to a Specialist Clinic and to examine the relationship of poor adherence to asthma outcome.

Methods: General practitioner prescription refill records for the previous 6 months for inhaled combination therapy and short-acting beta-agonists were compared with initial prescriptions and expressed as a percentage. Blood plasma prednisolone and cortisol assay levels were used to examine the utility of these measures in assessing adherence to oral prednisolone. Patient demographics, hospital admissions, lung function, oral prednisolone courses, and quality of life data were analyzed to indentify the variables associated with reduced medication adherence.

Measurements and main results: A total of 182 patients were assessed. Sixty-three patients (35%) filled 50% or fewer inhaled medication prescriptions; 88% admitted poor adherence with inhaled therapy after initial denial. Twenty-one percent of patients filled more than 100% of presciptions, and 45% of subjects filled between 51 and 100% of prescriptions. Twenty-three of 51 patients (45%) prescribed oral steroids were found to be nonadherent.

Conclusions: A significant proportion of patients with difficult-to-control asthma remained nonadherent to corticosteroid therapy. Objective surrogate and direct measures of adherence should be performed as part of a difficult asthma assessment and are important before prescibing expensive novel biological therapies.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Administration, Inhalation
  • Administration, Oral
  • Adult
  • Anti-Inflammatory Agents / blood
  • Anti-Inflammatory Agents / therapeutic use*
  • Anxiety Disorders / complications
  • Asthma / blood
  • Asthma / complications
  • Asthma / drug therapy*
  • Cross-Sectional Studies
  • Depressive Disorder / complications
  • Drug Prescriptions / statistics & numerical data
  • Female
  • Humans
  • Hydrocortisone / blood
  • Male
  • Medication Adherence / statistics & numerical data*
  • Prednisolone / blood
  • Prednisolone / therapeutic use*
  • Prevalence
  • Quality of Life
  • Retrospective Studies
  • Treatment Outcome


  • Anti-Inflammatory Agents
  • Prednisolone
  • Hydrocortisone