Importance of spirometry in primary care

Spirometry is the most used pulmonary function test today. Spirometry in primary care aids the diagnosis of various pulmonary and cardiovascular conditions, and plays a vital role in their prevention. For the last decade, it has become standard at the GP office [1]. However, it is essential to perform it properly.

In this blog you will learn:

What is spirometry?

Spirometry is a non-invasive diagnostic method that measures the lung function through the speed and volume of the air that a person inhales or exhales. It is a tool with a wide range of usability, which includes:

• lung function monitoring
• evaluation of chest pain and dyspnea
• monitoring the therapy when treating pulmonary conditions
• detecting pulmonary diseases
• evaluation of respiratory disabilities or impairment
• assessment of operative risk
• control of occupational-related lung diseases. [1]

Why spirometry in primary care?

In general practice, spirometry is mostly used for early diagnosis of asthma and COPD. We also use it for monitoring risk factors such as smoking, dust and gas exposure, and for monitoring patients treated for related issues. It also helps differentiate between cardiovascular and respiratory conditions [1]. In all these ways, it contributes to the reduction of the number of patients in secondary care and lowers the healthcare costs while offering quick results to the general practitioner (GP) [3, 4].

Apart from helping to diagnose the status of the lungs, however, it also sheds light on the complex interconnection of the major organs (lungs, heart, brain) with the rest of the body. This contributes to the identification of their diseases for timely treatment. For this reason, routine pulmonary function tests should be performed in every patient having or under suspicion of having a respiratory condition. The same applies to patients who receive general anaesthetics, transplants and treatment for cancer and other chronic diseases [2].

A detailed presentation of the role of spirometry in primary care, its measurement and interpretation is provided in this video lecture by Ivan Pecev, MD [1]:

Spirometry in primary care diagnosis

Obstructive lung conditions

In primary care, spirometry is frequently used in diagnosing obstructive lung diseases, e.g. asthma, chronic bronchitis or chronic obstructive pulmonary disease (COPD). These conditions are quite common and primary care spirometry measurements are instrumental in their detection. For example, it is possible to differentiate between obstructive and other conditions by means of spirometry alone [5]. Early diagnosis of obstructive conditions at primary care level can make a great difference. As many as one third of patients with first hospitalisation for COPD have not been previously diagnosed. [6]

Asthma is a common chronic inflammatory respiratory condition of obstructive nature. It manifests as shortness of breath, wheezing, coughing and tightness in the chest [13]. Extremely similar or virtually identical symptoms can be observed in those with acute bronchitis, which is a very common condition [14, 15, 16], but some cases of bronchitis may progress to chronic obstructive pulmonary disease (COPD) that has a significantly worse prognosis [17].

Some of those symptoms, like tightness in the chest, may also be indicative of possible cardiovascular issues, like coronary artery disease (CAD) or even myocardial infarction (MI). Spirometry helps differentiate between them and respiratory issues.

Spirometry in primary care is suitable for diagnosing and assessing the severity of asthma, differentiating between obstructive and restrictive lung diseases, identifying individuals at risk of pulmonary barotrauma, and for following the natural history of disease in respiratory conditions [18, 19, 20].

Restrictive and other lung conditions

Less frequently, spirometry is also used in diagnosing restrictive lung disorders; these restrict the lung expansion and thus the lung volume. Mixed conditions and conditions of respiratory muscle weakness, however, usually call for additional testing, often for the full pulmonary function laboratory. [3]

Early detection and diagnosis of lung conditions has the following benefits: [7]

• early interventions for reduction of risk factors (cardiovascular disease, smoking, occupational and environmental hazards)
• better management of conditions
• optimal treatment
• reduction of acute admissions
• optimised resource utilisation
• improved healthy life expectancy and quality of life.

Spirometry in primary care prevention

Despite many awareness campaigns and a multitude of well-defined research into the health risks of tobacco consumption, there are still many active smokers worldwide (an estimated 1.1 billion) [8]. Their numbers are fortunately declining, but very slowly, leaving many at significantly greater risk of lung and other types of cancer, cardiovascular diseases (CVDs) and generally decreased pulmonary function [8, 9 10, 11].

Evidence shows that spirometry could be used to successfully motivate patients in the early stages of COPD to quit smoking; 13.6% of patients provided who received interpreted spirometric data quit smoking as opposed to 6.4% of those whose data was not interpreted for them. [12]

How to measure spirometry?

Since the turn of the 20th century, the sphygmomanometer has been considered essential in the diagnosis and management of hypertension. The same goes for the measurement of blood glucose to diagnose and manage diabetes more recently. In contrast, chronic obstructive pulmonary disease (COPD) and asthma are frequently diagnosed and managed purely on the basis of history and physical findings [21]. This can result in misdiagnosis, overdiagnosis, underdiagnosis, and inappropriate management [22, 23].

Major references like the Canadian Thoracic Society (CTS) on COPD [24] and asthma [25] guidelines and European diagnostic spirometry guidelines [26] make it clear that spirometry should be considered part of the standard of care.

In a recent study [27], routine primary care spirometry tests were regarded highly clinically useful by GPs and pulmonologists alike – in connection with 88% of the tests. In addition, more than 80% of the tests were also assessed as good in quality. In terms of diagnosis, the agreement on the diagnosis between GPs and pulmonology specialists was low, but that does not diminish the importance of pulmonary disease detection at primary care level.

Education has a positive effect on the quality of spirometry in primary care [28, 29]. Here is a detailed description of all essential spirometry values and the technology for accurate spirometry at the primary and advanced levels.

Ivan Pecev, MD

Specialist of family medicine

Doctor Pecev is a family medicine specialist at the Arcus Medici outpatient clinic in Žiri, Slovenia, where they place emphasis on modern and professional treatment of their patients. For this purpose, they have developed a unique model of preventive medical treatment. He also participated as the co-author of the handbook entitled “Physical activity for better health and well-being”.