Even among patients who do receive a diagnosis of COPD , spirometry is underutilized. In a 2007 review of over 5000 patients newly diagnosed with COPD, just 32 % had any PFTs prior to disease diagnosis [4]. Similarly, a review of around 200,000 Veteran Affairs patients newly diagnosed with COPD found the frequency of spirometry testing was around 34 % [5]. Both studies found the frequency of spirometry testing lower among older patients. Additionally, several studies have established that the burden of asthma and respiratory disease is not uniform across all patient groups. Ethnic minorities and those with lower socioeconomic status (SES) have increased morbidity and mortality related to asthma, with lack of access to healthcare, including PFTs, implicated [6–13].

The lack of routine PFTs in these settings has a number of potential consequences for patient care. Limited use of PFTs in the initial evaluation of patients with possible COPD has been shown to increase the risk of underdiagnosis of COPD. Confirmation of the diagnosis of asthma/COPD with PFTs results in better overall care, giving providers greater confidence in prescribing medications appropriately for moderate to severe COPD, such as anticholinergic inhaler therapy and long-acting beta agonists [14]. Additionally, there is a risk of misdiagnosis or “overdiagnosis ,” with patients being exposed to treatments for conditions they don’t have, as well as delayed or missed diagnosis of other serious disorders. Misdiagnosis can also lead to patients being “labeled” with chronic medical conditions, with resulting psychosocial stigmata, as well as increased premiums for health and life insurance. When COPD or asthma is misdiagnosed, often due to lack of spirometry, prescription of inhaled bronchodilator medications can be ineffective and wasteful. This is particularly true when patients experience an apparent response to therapy because of spontaneous resolution of self-limited conditions such as viral respiratory tract infections. This can result in undesirable medication side effects, as well as financial burden from having to purchase inhalers or nebulizers. Many inhalers have a monthly cost of $100–$300, so this financial burden may be considerable.

Many factors may contribute to underutilization of spirometry in primary care settings, , but exact reasons for underutilization have not been adequately explored. Many laboratories have substantial wait times prior to pulmonary function testing being available. Long waiting times (as long as several weeks) may be a sufficient disincentive to prevent some otherwise appropriate testing. In our pulmonary function laboratory, we operate with the assumption that “unmet demand goes away” and manage test availability with a targeted maximum wait time of 2 days and immediate accommodation of patients who show up requesting immediate testing.

Perhaps the greatest contributing factor to lack of test availability is lack of the most expensive component of the testing system: well-trained staff who can coach patients to perform acceptable and repeatable PFTs. Comprehensive technician training and a program of quality assurance and feedback have been shown to improve the quality of spirometry results [15]. The American Thoracic Society (ATS) and the European Respiratory Society (ERS ) have published standardization guidelines for spirometry [16, 17]. In surveys of general practitioners, lack of confidence in the quality of the spirometry measure was felt to be a major limitation to widespread utilization of PFTs in primary care practice [18]. Prior studies noted that spirometry performed in family practice settings without technician training frequently does not satisfy ATS/ERS criteria for acceptability and repeatability. However, following relatively simple training, the proportion of maneuvers achieving quality standards increased substantially, highlighting the importance of effective training and quality assurance programs to ensure successful spirometry in primary care practice [19]. Crucially, several studies have demonstrated that when spirometry is performed in primary care practices by healthcare professionals trained to appropriately coach patients through spirometry maneuvers, the quality of spirometry results was comparable to those performed in a specialist-run pulmonary function laboratory [20].

As noted earlier, the utilization of PFTs in newly diagnosed COPD cases is lower among older patients [4, 5]. Part of this age discrepancy may be out of concern for poor test quality in older adults . In the SARA study , spirometry reproducibility and acceptability was assessed for older adults (>65 years) undergoing PFTs for the diagnosis of asthma or COPD. Investigators found that testing in older adults typically required more time and more attempts. However, if this was done with rigorous quality control measures implemented, good spirometry test quality was achievable with result quality comparable to that among younger patients. Cognitive impairment, a shorter 6-min walk distance, and lower educational level were all found to be independent predictors for a poorer acceptability rate [21].

Spirometry certification programs exist both nationally and internationally to provide the necessary training. In the United States, certification was established through the Cotton Dust Standard [29 CFR 1910.1043] and is coordinated by the National Institute for Occupational Safety and Health (NIOSH ). Initial certification requires 15 h of training. A 1-day recertification program is required every 5 years. In addition to time and money, another potential roadblock to certification is not having geographical proximity to one of the NIOSH-approved training centers [22]. In primary care clinics where adequate technician training limits the availability of quality PFTs, a possible alternative is spirometry performed locally within the clinic, but coordinated and coached online by certified technicians working at a separate pulmonary function laboratory. This concept has been shown to provide an adequate alternative to conventional spirometry in primary care centers [23]. Once staff members have been appropriately trained to perform spirometry or other tests, ongoing staff management is required to provide test availability when needed. In the primary care setting , this includes juggling of other duties for busy staff who may be nurses, respiratory therapists, phlebotomists, or other laboratory or clinical personnel. Most have other tasks that must be prioritized.

Equipment availability, by contrast, is probably rarely a legitimate limitation to availability of PFTs in the United States and other developed countries. Although pulmonary function equipment capable of complete PFTs (including lung volumes and diffusing capacity in addition to spirometry) typically cost more than $30,000, a simple office spirometer can be purchased for under $1000, and a more comprehensive spirometry system can be purchased for less than $5000 complete with computer and printer. Medicare reimbursement for spirometry with bronchodilator is over $70 per test, though Medicaid reimbursement is less. The test requires 20–30 min of staff time and the only disposable cost is for a filter/mouthpiece, which typically costs $1–5. Reimbursement for healthcare services in the United States typically underpays for cognitive services but overpays for procedural services, so the underutilization of spirometry seems curious and illogical. As stated earlier, we believe lack of timely test availability is a major unrecognized contributing factor.

As discussed elsewhere in this text, asthma has increased disease prevalence among low-income and inner-city communities, those with lower educational attainment (high school or less), women, and African-Americans [13]. Over time, there has been a widening of the racial differences in asthma severity , with studies suggesting African-Americans may be more likely to have asthma hospitalizations, greater severity of disease, and higher asthma-related mortality [8, 10–12]. Cigarette smoking remains a major modifiable risk factor for developing respiratory diseases, and the burden of cigarette smoking is similarly disproportionate—greater in those living below the poverty level, with lower educational levels, and within certain ethnicities (particularly Native Americans) [24, 25]. The prevalence of cigarette smoking has declined over time, thanks to concerted public health campaigns, increased taxation on cigarettes, prohibition of indoor cigarette smoking, antitobacco mass media campaigns, and barrier-free access to smoking cessation aids [24]. These public health efforts need to continue and should be focused on communities and groups in which prevalence of cigarette smoking remains high. Inner-city communities also have increased exposures to airborne particulate matter and other vehicle emissions [26, 27]. These exposures have been linked to declines in lung function in the general population [27, 28], which are likely even greater for the elderly and patients with chronic respiratory conditions [29]. Other potentially significant exposures seen more commonly among inner-city residents include inhaled drugs such as crack cocaine and greater exposure to certain antigens such as from cockroaches and dogs [30–32].

Inner-city and poorer communities also have lower doctor-to-patient ratios, resulting in less time per clinic visit, less continuity of care, greater proportion of care in emergency room and urgent care settings, as well as longer waiting times for routine appointments [33, 34]. Quality of asthma care has been shown to be lower for inner-city patients with asthma, particularly within ethnic minorities and those living in poorer neighborhoods [6, 7, 9, 12]. In these time-pressured settings, often in urgent care centers without established patient–provider relationships, diagnostic accuracy including evaluation with spirometry may be neglected in favor of “quick fixes” such as empiric antibiotics, rescue inhalers, and oral corticosteroids. Patients may have lower rates of insurance coverage and indicated diagnostic testing such as spirometry may be skipped because of patients’ inability to pay [34].

Another barrier to access may be lack of transportation . In the inner-city setting, testing facilities are likely to be close—within a few miles of a patient. However, in the absence of affordable, accessible, and safe mass transit systems, getting to clinics may be time or cost prohibitive. In the rural setting , including Native American reservations, the opposite problem exists, where distances may be great. Consequently, patients require not only vehicles, but also money for gasoline and the ability to take time off from work. Again, this can be time and cost-prohibitive. The ultimate result is less access to PFTs, and a greater proportion of patients with underdiagnosed, misdiagnosed, or mismanaged pulmonary conditions, including not only asthma and COPD, but also other less common conditions which are frequently misdiagnosed as asthma or COPD until more thoughtful evaluation is pursued.