Background Advanced chronic obstructive pulmonary disease (COPD) often leads to hospitalisation and invasive aspergillosis (IA) is a serious complication. Aspergillus sensitisation may worsen symptoms in COPD. Methods We identified published papers between January 2000 and May 2019 with > 50 subjects and GOLD criteria for grade II, III or IV (FEV1/FVC < 70% and FEV1 < 80%) using standardised criteria in multiple countries, to re-estimate the prevalence of COPD. Hospitalised COPD patients develop IA in 1.3–3.9%, based on positive cultures of Aspergillus spp. and radiological findings. Given limited data on per-patient annual hospitalisation rates, we assumed a conservative 10.5% estimate. Annual IA mortality in COPD was estimated using the literature rates of 43–72%. A separate literature search assessed the impact of Aspergillus sensitisation on severity of COPD (by FEV1). Results We re-estimated the global prevalence of COPD GOLD stages II-IV at 552,300,599 people (7.39% of the population) with 339,206,893 (8.58%) in Asia, 85,278,783 (8.52%) in the Americas, 64,298,051 (5.37%) in Africa, 59,484,329 (7.77%) in Europe and 4,032,543 (10.86%) in Oceania. An estimated 57,991,563 (10.5%) people with COPD are admitted to hospital annually and of these 753,073 (1.3%) – 2,272,322 (3.9%) develop IA and 540,451–977,082 deaths are predicted annually. Aspergillus sensitisation prevalence in COPD was 13.6% (7.0–18.3%) and not related to lower predicted FEV1% (P > 0.05). Conclusions The prevalence of COPD is much higher than previously estimated. Overall COPD mortality may be higher than estimated and IA probably contributes to many deaths. Improved rapid diagnosis of IA using culture and non-culture based techniques is required in COPD hospital admissions to reduce mortality.

Background Advanced chronic obstructive pulmonary disease (COPD) often leads to hospitalisation and invasive aspergillosis (IA) is a serious complication. Aspergillus sensitisation may worsen symptoms in COPD. In 2016, the global estimate of COPD was 251 million affected. Methods We identified published papers between January 2000 and May 2019 with >50 subjects and GOLD criteria for grade II, III or IV (FEV1/FVC <70% and FEV1 <80%) using spirometry. Given limited data, a conservative 10.5% estimate of annual hospitalisation was assumed based on studies in Algeria. A separate literature search assessed the impact of Aspergillus sensitisation on severity of COPD (by FEV1). Hospitalised COPD patients develop IA in 1.3% -3.9%, based on positive cultures of Aspergillus spp. and radiological findings. Mortality was estimated based on the diagnosis of IA being made and patients treated. Results We re-estimated the global prevalence of COPD GOLD stages II-IV at 552,300,599 people (7.39% of the population) with 339,206,893 (8.58%) in Asia, 85,278,783 (8.52%) in the Americas, 64,298,051 (5.37%) in Africa, 59,484,329 (7.77%) in Europe and 4,032,543 (10.86%) in Oceania. Aspergillus sensitisation prevalence in COPD was 13.6% (7.0-18.3%) and not related to lower predicted FEV1% (P >0.05). An estimated 57,991,563 (10.5%) people with COPD are admitted to hospital annually and of these 753,073 (1.3%) - 2,272,322 (3.9%) develop IA and 540,451 – 977,082 deaths (43-72%) are predicted annually, assuming the diagnosis is made and treatment given. Conclusions: The prevalence of COPD is much higher than previously estimated. Mortality may be higher that estimated as not all diagnosis of IA is probably made. Improved rapid diagnosis of IA using culture and non-culture based techniques is required in COPD hospital admissions to reduce mortality.

Islam et al. This is an open access article distributed under the terms of the Creative Commons Attribution License CC-BY 4.0., which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.