About asthma and associated comorbidities

Comorbidity

Some people with asthma have other chronic diseases and long-term conditions. These are referred to as comorbidities—two or more health problems present at the same time. For people with asthma, having a comorbid chronic condition can have important implications for their health outcomes, quality of life and treatment choices.

Australians diagnosed with one or more chronic conditions often have complex health needs, die prematurely and have poorer overall quality of life [1]. In terms of comorbidities, in 2017–18 one in five Australians (20%) had two or more chronic conditions [2]. The chance of developing chronic conditions increases with age, and since asthma often starts early in life, people with asthma are likely to develop another chronic condition during their lifespan. For example, in 2017–18, an estimated 91% of people aged 65 and over with asthma also had one or more additional chronic conditions, compared to 52% for people aged 15–44 and 75% for people aged 45–64, based on self-reported data [2].

Asthma in adults is associated with obesity, mental disorders, arthritis and cardiovascular disease [3, 4].

The chronic conditions that have been selected for this asthma comorbidity analysis are: arthritis, back problems, cancer, chronic obstructive pulmonary disease (COPD), diabetes, heart, stroke and vascular disease, kidney disease, mental and behavioural conditions and osteoporosis. They have been selected because they are common in the general community and cause significant burden.

Other chronic conditions that are commonly found in people with asthma, and that can impact on asthma, include allergic rhinitis, obstructive sleep apnoea, and gastro-oesophageal reflux disease [5].

Having a history of asthma is a major risk factor for being diagnosed with COPD, particularly for smokers [6, 7]. There is increasing recognition of asthma-COPD overlap (also called asthma-COPD overlap syndrome, or ACOS). Overall, approximately 20% of patients with obstructive airway disease have been diagnosed with both asthma and COPD [8] (for more information on prevalence, see Asthma-COPD overlap 2017). It is important to identify people with asthma-COPD overlap, because they are at higher risk than patients with asthma or COPD alone, and because they should be treated differently from people with asthma or COPD alone [9]. The National Asthma Council Australia & Lung Foundation recently released an information paper on Asthma-COPD overlap, which includes recommendations for the treatment and management of the condition [9].

The National Asthma Strategy 2018 (the Strategy) was launched in January 2018. The Strategy aims to outline Australia’s national response to asthma and inform how existing limited health care resources can be better coordinated and targeted across all levels of government [10]. The Strategy identifies the most effective and appropriate interventions to reduce the impact of asthma in the community and continue to be an international leader in asthma prevention, management and research [10]. The Strategy notes that the presence of one or more comorbid conditions in people with asthma is likely to compromise their quality of life and may complicate their management of asthma [10]. The AIHW will monitor and report on the outcome measures associated with the Strategy by reporting on the 10 national asthma indicators. For more information, see National Asthma Strategy 2018.

Treatment and management

Management of asthma includes medicines to minimise symptoms such as shortness of breath, wheezing and coughing, and to reduce the risk of adverse outcomes, such as flare-ups.

Treatment of comorbidities depends on individual patient needs. As recommended in the Australian Asthma Handbook, some comorbidities such as obesity, mental illness, allergic rhinitis and obstructive sleep apnoea, should be treated not only to improve patient health outcomes, but to also reduce their impact on asthma control and risk of flare‑ups [11].

Medications prescribed for some comorbidities may interact with each other, which can cause problems for people with asthma. One example is beta-blockers, a treatment sometimes used for cardiovascular disease, glaucoma or anxiety. In people with asthma, beta-blockers given by tablet or eye-drops can cause severe asthma flare-ups, requiring more intense treatment and management. Another example is non-steroidal anti-inflammatory medications (NSAIDs) including aspirin, which may be used to treat cardiovascular disease or arthritis. These medications can cause severe flare-ups in around 7% of people with asthma [12].

For patients who have both asthma and COPD, treatment usually includes inhaled corticosteroids (anti-inflammatory medications) and long-acting bronchodilators together with treatment of modifiable risk factors such as smoking cessation, increasing physical activity, pulmonary rehabilitation, and vaccinations [11]. Short-acting bronchodilators are also to be used as needed for symptom relief.

Due to the potential for interactions between different chronic conditions and the medications used to treat them, it is important that people with asthma tell their doctor(s) about any other conditions that they have, and any other treatment they are taking, so that their health can be carefully monitored.

References

  1. Australian Institute of Health and Welfare (AIHW) 2018. Australia’s health 2018. Australia’s health series no. 16. AUS 221. Canberra: AIHW.
  2. Australian Bureau of Statistics (ABS) 2018. National Health Survey: First Results, 2017–18. ABS Cat. no. 4364.0.55.001. Canberra: ABS.
  3. Caughey GE, Vitry AI, Gilbert AL & Roughhead EE 2008. Prevalence of comorbidity of chronic diseases in Australia. BMC Public Health 8.
  4. Cazzola M, Calzetta L, Bettoncelli G, Cricelli C, Romeo F, Matera MG et al. 2012. Cardiovascular disease in asthma and COPD: A population-based retrospective cross-sectional study. Respiratory Medicine 106.
  5. Boulet L-P, 2009. Influence of comorbid conditions on asthma. European Respiratory Journal. 33(4): 897-906.
  6. Van der Molen T. 2010. Co-morbidities of COPD in primary care: frequency, relation to COPD, and treatment consequences. Primary Care Respiratory Journal, 19(4): 326–334.
  7. de Marco R, Pesce G, Marcon A, Accordini S, Antonicelli L, Bugiani M, et al. 2013. The coexistence of asthma and chronic obstructive pulmonary disease (COPD): Prevalence and risk factors in young, middle-aged and elderly people from the general population. PloS One 8(5): e62985.
  8. Gibson PG & McDonald VM. 2015. Asthma—COPD overlap 2015: now we are six. Thorax; 70: 683-91.
  9. National Asthma Council Australia & Lung Foundation Australia 2017. Asthma-COPD overlap. Melbourne, National Asthma Council Australia.
  10. Department of Health 2017. National Asthma Strategy 2018. Canberra: Department of Health.
  11. National Asthma Council Australia. Australian Asthma Handbook, Version 2.0. National Asthma Council Australia, Melbourne, 2019. Viewed 1 May 2019.
  12. Rajan JP, Wineinger NE, Stevenson DD, White AA. 2015. Prevalence of aspirin-exacerbated respiratory disease among asthmatic patients: A meta-analysis of the literature. Journal of Allergy and Clinical Immunology. 135: 676-81.e1.