More than half of adult Greenlanders smoke. Nevertheless, the prevalence of chronic obstructive pulmonary disease (COPD), associated with smoking, has seemed surprisingly low. However, a new study finally dispels that myth. Like elsewhere in the world, about 1 in 10 smokers in Greenland develop this severely disabling and fatal lung disease – even younger people. The lack of reference values for lung function among Greenlanders contributed to underestimating COPD in Greenland. According to the researchers, the study emphasizes the importance of initiatives to reduce smoking in Greenland.
They work at very low temperatures, standing all day in the processing plants – in the stench of boiled crabs and shrimp – only interrupted by a few smoking breaks. Conditions for employees in the fishing industry are harsh everywhere, including Greenland, and contribute to disease. Somewhat surprisingly, however, studies have indicated that the prevalence of one of the most common fatal diseases in other countries – COPD – is nearly 0 in Greenland.
“We therefore examined the incidence of COPD and chronic bronchitis among 355 seafood industry workers of Inuit origin in Greenland. 73% were active smokers, and smoking was clearly associated with both COPD and bronchitis. Among those younger than 40 years, as many as 10% had COPD. In addition, the reason why the prevalence of these diseases has been hidden is that the Inuits’ normal lung capacity has been underestimated. They may therefore appear not to be harmed by smoking,” explains Michael Lynge Pedersen, medical director at Steno Diabetes Center Greenland.
More than 65 million people worldwide have moderate or severe COPD, and projections suggest that this number will continue to rise worldwide for at least the next 50 years. More than 90% of those affected are smokers, which manifests itself in increasing cough, shortness of breath and more frequent infections as the airways narrow and the lung tissue is destroyed. For many, chronic bronchitis is a step on the way.
“1 in 10 smokers worldwide develop COPD, so we could not understand why COPD seemed to be virtually absent in Greenland, and we thought that COPD has probably been underdiagnosed. This was confirmed by a recent study from Greenland, since 7.5% of the population use drugs for COPD, even though only one third of them have been tested with a spirometer. We therefore decided to try to investigate this more thoroughly,” explains another author, Jakob Hjort Bønløkke, Chief Physician at Aalborg University Hospital and Clinical Associate Professor at Aalborg University.
A total of 355 workers from fish and shellfish factories, 254 men and 101 women, participated. They were between 17 and 68 years old and averaged 38 years old. Nine of 10 had smoked at some time, and almost 3 of 4 still smoked. To avoid misdiagnosis, everyone with asthma was excluded by testing whether asthma medication worked. The rest were then tested with a spirometer to measure how much and how rapidly air can be exhaled from the lungs.
“The participants also completed a questionnaire to diagnose bronchitis, a permanent inflammatory condition of the bronchial mucosa that is usually also caused by smoking. 7.4% had bronchitis and 9.9% had COPD, so that is exactly the same prevalence as in the rest of the world. The problem is that Greenland has a significantly higher percentage of smokers than in the rest of the world, so this is a very big health problem,” explains Jakob Hjort Bønløkke.
The key to the new results has been not to use standard references for lung function for Caucasians. Instead, the researchers tried to create a standard for normal lung function among Inuit, and it seems to be significantly higher than previously thought.
“Inuit have a slightly different physique – with slightly shorter legs, which is why their normal lung capacity has been underestimated in the past. The percentage of lung capacity a smoker has lost can therefore also easily be underestimated. You may seem to have lung capacity of 70% even though it is down to 40%, and since time is the crucial factor in being able to optimally stop and treat COPD, early diagnosis is very, very important,” says Jakob Hjort Bønløkke.
Smoking cessation is the only intervention
With the new study finding that smoking is also a risk factor for COPD and chronic bronchitis among Greenlanders of Inuit origin, the question naturally arises as to what should be done about the problem. Michael Lynge Pedersen emphasizes that one effort must focus on detecting and treating those with COPD in time. This requires better equipment and more frequent check-ups – a focus of the relatively new Steno Diabetes Center Greenland.
“The lack of reference values for Inuit lung function has contributed to underestimating the prevalence of COPD in Greenland. We are therefore conducting a larger study to determine reference values for Inuit lung function. And then we need to disseminate the knowledge and ability to detect the persistent airflow restriction through spirometry that is required to diagnose COPD,” explains Jakob Hjort Bønløkke.
The vision for Steno Diabetes Center Greenland is therefore not only to focus on diabetes but also the other widespread lifestyle-related diseases such as COPD and cardiovascular disease. The Center must focus on improving diagnosis and treatment, but especially also prevention.
“Smoking cessation is the only intervention that has been shown to slow down the decline in lung function. However, smoking cessation can only improve lung capacity by about 7 percentage points, so prevention is the most important initiative to combat COPD,” says Jakob Hjort Bønløkke.
Lung cancer is also the most common type of cancer in Greenland, comprising 34% of all cancer deaths, and the prevalence of heavy smoking is higher among younger Greenlanders than older ones. Some initiatives have been taken to reduce smoking in Greenland.
“Nevertheless, the prevalence of smokers in Greenland is still high. 52% of Greenlandic adults smoke versus 23% in Denmark, and the high prevalence among young adults is especially worrying. The high incidence of smoking-related COPD in the new study emphasises the importance of further initiatives to reduce smoking in Greenland,” concludes Jakob Hjort Bønløkke.