The prevalence of comorbidities in COPD patients, and their impact on health status and COPD symptoms in primary care patients: a protocol for an UNLOCK study from the IPCRG

Chronic obstructive pulmonary disease (COPD) is an important cause of morbidity and mortality with high social and economic costs. The prevalence of COPD has been reported to vary between 6 and 26.1% worldwide.1 COPD has also been associated with a high prevalence of one or more comorbid conditions, which have an impact on health status and mortality.2,​3,​4,​5 Although several diseases have been studied as COPD comorbidities6,7 few studies have looked at the issue of multimorbidity in COPD.8,​9,​10

COPD, like other chronic disorders, has been associated with comorbidities that increase in number and severity with age, and are more prevalent among deprived social groups.5,8 There is evidence that comorbidities increase the risk for exacerbations, reduce health status, and increase the risk of mortality.5,8 COPD guidelines (e.g., GOLD recommendations) still consider the diagnosis and management of comorbidities from an individual disease point of view.11 Consequently, health services focus on individual diseases rather than multimorbidity.10,​11,​12,​13 A better knowledge of the prevalence and impact of multimorbidity facing COPD patients in primary care would help to evaluate whether a different approach (i.e., multimorbidity) should be taken.

Research on the prevalence of comorbidities among patients with COPD and their impact on health status in primary care patients is scarce. Most studies that evaluated the spectrum and prevalence of comorbidities affecting COPD patients have been conducted in secondary care settings. For example, Divo et al.4 found a relationship between comorbidities and the risk of death over 51 months. Anxiety, cancers, and heart diseases are among the most significant comorbid diseases associated with COPD mortality risk in secondary care settings.4 Increasing knowledge about COPD comorbidities in primary care is essential for the development of better intervention strategies and for reframing clinical guidelines.

This is a unique opportunity to evaluate the impact of individual comorbidities and multimorbidity on COPD patients in primary care in different settings.