The Utility of Spirometry in Diagnosing Pulmonary Restriction

The aim of this retrospective study was to determine the utility of the spirometric measurements FVC, FEV₁, and FEV₁/FVC in diagnosing pulmonary restriction. Spirometry and lung volume measurements performed on the same patient visit were analyzed. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of (1) FVC < lower limit of normal (LLN) (NHANES III reference values) and (2) FVC < LLN and FEV₁/FVC ≥ LLN were compared to diagnose restriction based on lung volume measurements. In all, 18,282 pulmonary function tests from 8,315 patients were analyzed. Twenty-six percent of the patients (n = 2,213) had restriction based on lung volume measurements. The sensitivity, specificity, PPV, and NPV of FVC < LLN to diagnose restriction based on lung volume measurement criteria were 88.6%, 56.8%, 39.9%, and 93.9%, respectively. The sensitivity, specificity, PPV, and NPV of FVC < LLN and FEV₁/FVC ≥ normal to diagnose restriction based on lung volume criteria were 72.4%, 87.1%, 64.4%, and 90.7%, respectively. Analysis of ROC curves showed that spirometric criteria based on FVC alone performed better (area under the curve = 0.817) than those based on the combined criteria of FVC and FEV₁/FVC (area under the curve = 0.584). Consistent with earlier findings, the negative predictive value for a normal FVC (≥ LLN) to exclude pulmonary restriction was high in this series (up to 95.7%). Also, a spirometric diagnosis of “restriction” (FVC < LLN and FEV₁/FVC ≥ LLN) had a positive predictive value of 26.3–73.9%. On this basis, normal FVC can be regarded as excluding restriction with high reliability. Saiprakash B. Venkateshiah and Octavian C. Ioachimescu authors contributed equally to this work.     

Spirometry in primary care: An analysis of spirometry test quality in a regional primary care asthma program

BACKGROUND:

Primary care office spirometry can improve access to testing and concordance between clinical practice and asthma guidelines. Compliance with test quality standards is essential to implementation.

OBJECTIVE:

To evaluate the quality of spirometry performed onsite in a regional primary care asthma program (RAP) by health care professionals with limited training.

METHODS:

Asthma educators were trained to perform spirometry during two 2 h workshops and supervised during up to six patient encounters. Quality was analyzed using American Thoracic Society (ATS) 1994 and ATS/European Respiratory Society (ERS) 2003 (ATS/ERS) standards. These results were compared with two regional reference sites: a primary care group practice (Family Medical Centre [FMC], Windsor, Ontario) and a teaching hospital pulmonary function laboratory (London Health Sciences Centre [LHSC], London, Ontario).

RESULTS:

A total of 12,815 flow-volume loops (FVL) were evaluated: RAP – 1606 FVL in 472 patient sessions; reference sites – FMC 4013 FVL in 573 sessions; and LHSC – 7196 in 1151 sessions. RAP: There were three acceptable FVL in 392 of 472 (83%) sessions, two reproducible FVL according to ATS criteria in 428 of 469 (91%) sessions, and 395 of 469 (84%) according to ATS/ERS criteria. All quality criteria – minimum of three acceptable and two reproducible FVL according to ATS criteria in 361 of 472 (77%) sessions and according to ATS/ERS criteria in 337 of 472 (71%) sessions. RAP met ATS criteria more often than the FMC (388 of 573 [68%]); however, less often than LHSC (1050 of 1151 [91%]; P<0.001).

CONCLUSIONS:

Health care providers with limited training and experience operating within a simple quality program achieved ATS/ERS quality spirometry in the majority of sessions in a primary care setting. The quality performance approached pulmonary function laboratory standards.     

Chronic obstructive pulmonary disease in Brazilian primary care: Diagnostic competence and case-finding.

AIMS: The developing world is particularly at risk of an increasing health burden due to an increased prevalence of Chronic Obstructive Pulmonary Disease (COPD) secondary to increasing tobacco consumption. However, research is scarce. The objectives of this study were to assess the current competence for diagnosing COPD in primary care in a resource-limited setting in Brazil, and to develop a local patient profile for case-finding. METHODS: 34 general practitioners (GPs) in five areas of northern Brazil recruited adult patients with principal complaints of cough and/or shortness of breath who then had spirometry (n = 142). RESULTS: For the dichotomous variable 'COPD' the degree of agreement between GP diagnosis (n = 64, 18.3%) and spirometric outcome (n = 36, 25.4%) was poor, with Kappa = 0.055 (SE 0.087) and DOR = 1.35. False-positive and false-negative diagnosis proportions were 19.8% and 75%, respectively. Independent risk factors were 'smoking history of more than five pack years' and 'presence of both dyspnoea and cough'. It requires the testing of 2.2 smokers with more than five pack years to detect one patient at risk. CONCLUSIONS: COPD is a common yet underdiagnosed disease in Brazilian primary care. Spirometry improves diagnostic competence and case-finding substantially. If applied in a pre-selected high-risk population, we believe spirometry can be a cost-effective diagnostic tool for case-finding in the resource-limited setting. This study provides important baseline information for effective guideline implementation.     

Electronic clinical reminder and quality of primary diabetes care

Aims

To study the association of EMR’s clinical reminder use on a comprehensive set of diabetes quality metrics in U.S. office-based physicians and within solo- versus multi-physician practices. We conducted a retrospective cohort study on visits made by adults with diabetes identified from the National Ambulatory Medical Care Survey (2012–2014).

Normal Spirometric Reference Values for Omani Adults

International guidelines recommend the use of population-specific reference values to eliminate the well-recognized influence of ethnic variation on lung function. This study was designed to derive spirometric prediction equations for healthy Omani adults. Forced vital capacity (FVC), forced expiratory volume in one second (FEV₁), peak expiratory flow rate (PEFR), and forced expiratory flow at 25% to 75% of FVC (FEF_25–75%) were measured in 419 “healthy” nonsmoking Omani adults (256 men, 163 women), aged 18–65 years. Multiple linear regression analysis was performed for each spirometric parameter against age, height, and weight for men and women separately, and prediction equations for all the above parameters were derived and compared with values derived using equations published from other populations. All measured spirometric parameters increased with height and decreased with age, and they were all significantly higher in men. In contrast, FEV₁/FVC% values decreased with height and increased with age and were higher in women. The predicted normal values of FVC and FEV₁ for our subjects using the derived equations were lower by 7–17% compared with respective Caucasian values, with smaller difference in the predicted values of PEFR, FEV₁/FVC%, and FEF_25–75%. This report presents previously unavailable spirometric reference equations for the Omani adults. Our findings highlight the need to use reference values based on updated data derived from relevant populations.     

中国大型综合性医院肺量计检查报告质量的多中心调查

目的 了解我国肺量计检查报告质最控制现状.方法 收集2008年1-10月我国36家大型综合性医院肺功能室的肺量计检查报告单,参照ATS和ERS的肺活量测试标准进行质量分析,肺量计检查各质量控制标准的符合情况以百分率来描述.结果 共收集345例报告单,82.5%(282/342)的报告单符合测试起始质量的标准;65.8%(219/333)的报告单达到分析呼气流畅质量的标准,其余114例不符合标准的报告单中,咳嗽占8.7%(29/333),声门早闭占2.4%(8/333),口嘴漏气占8.7%(29/333),提前中止占7.8%(26/333),阻塞口器占1.8%(6/333),未尽最大努力占14.7%(49/333);50.6%(119/235)的报告单达到分析测试结束质量的标准;测试次数≥3次的占22.6%(78/345),其中65例有各次测试数据报告,可分析其重复性,符合标准的占95.4%(62/65),占总数的18.0%(62/345),AFVC＜150 ml的占95.4%(62/65),△FVC＜100 ml的占92.3%(60/65),△FEV_1＜150 ml的占100.0%(65/65),△FEV_1＜100 ml的占87.7%(57/65);在345例报告单中,同时符合上述4项标准的仅占总数的7.2%(25/345).结论 我国医院的用力肺功能检查质量有待提高.     

Diagnosis of heart failure in elderly patients in primary care

BACKGROUND: Heart failure is difficult to diagnose in a primary care setting with a reported false positive diagnosis in up to 70% of cases. Aims: To use echocardiography in a large rural practice to evaluate the accuracy of diagnosis of heart failure in patients over 65 years of age. METHODS: Sixty patients with a previous diagnosis of heart failure were selected at random from the practice records and were invited to attend for an echocardiogram at the practice premises. RESULTS: Fifty-eight patients attended, the age was 81+/-7 years, 29% had impaired left ventricular (LV) systolic function of whom 65% were in atrial fibrillation. A further 7% had isolated diastolic LV dysfunction. The prevalence of heart failure by clinical assessment was 29 per 1000 in this patient group and 9 per 1000 when echocardiography was used to confirm the diagnosis. CONCLUSION: True heart failure in this population is less prevalent than has been estimated from practice records.     

Canadian prediction equations of spirometric lung function for Caucasian adults 20 to 90 years of age: results from the Canadian Obstructive Lung Disease (COLD) study and the Lung Health Canadian Environment (LHCE) study

BACKGROUND:

Currently, no reference or normative values for spirometry based on a randomly selected Canadian population exist.

OBJECTIVE:

The aim of the present analysis was to construct spirometric reference values for Canadian adults 20 to 90 years of age by combining data collected from healthy lifelong nonsmokers in two population-based studies.

METHOD:

Both studies similarly used random population sampling, conducted using validated epidemiological protocols in the Canadian Obstructive Lung Disease study, and the Lung Health Canadian Environment study. Spirometric lung function data were available from 3042 subjects in the COLD study, which was completed in 2009, and from 2571 subjects in the LHCE study completed in 1995. A total of 844 subjects 40 to 90 years of age, and 812 subjects 20 to 44 years of age, were identified as healthy, asymptomatic, lifelong nonsmokers, and provided normative reference values for spirometry. Multiple regression models were constructed separately for Caucasian men and women for the following spirometric parameters: forced expiratory volume in 1 s (FEV₁), forced vital capacity (FVC) and FEV₁/FVC ratio, with covariates of height, sex and age. Comparison with published regression equations showed that the best agreement was obtained from data derived from random populations.

RESULTS:

The best-fitting regression models for healthy, never-smoking, asymptomatic European-Canadian men and women 20 to 90 years of age were constructed. When age- and height-corrected FEV₁, FVC and FEV₁/FVC ratio were compared with other spirometry reference studies, mean values were similar, with the closest being derived from population-based studies.

CONCLUSION:

These spirometry reference equations, derived from randomly selected population-based cohorts with stringently monitored lung function measurements, provide data currently lacking in Canada.     

Enhancing the accuracy of respiratory diagnoses in primary care: a report on the establishment of a Community Respiratory Assessment Unit

AIMS: To establish a Community Respiratory Assessment Unit and to evaluate its role in enhancing the accuracy of respiratory diagnosis in primary care. METHODS: We established a central and peripatetic nurse-led service utilising semi-structured history taking, spirometry, oxygen saturation monitoring and semi-structured reporting, coupled with the provision of educational materials to both primary care physicians and patients. RESULTS: Phased access to the service was offered to 32 general practices. Use varied widely between practices and a total of 364 patients were referred in the first year. The single biggest diagnostic group consisted of patients with definite or suspected COPD, but the diagnosis was often not confirmed. Patient and GP satisfaction with the service was extremely high; without it misdiagnoses and inappropriate therapeutic trials are possible. CONCLUSION: A community respiratory assessment unit such as this is one way of offering a centrally-directed, quality-controlled, diagnostic support service for primary care physicians.     

Office Spirometry: Equipment Selection and Training of Staff in the Private Practice Setting

SUMMARY

Spirometry is a basic pulmonary function test that is widely used for the detection of airflow limitation. Its use will continue to grow in the medical office setting because it is useful for both diagnostic and monitoring purposes. Additionally, the assessment of airflow reversibility is a quick, safe, and useful adjunct to baseline spirometry.

Many manufacturers offer various models and types of spirometers. Before purchasing, determine the needs and characteristics of the office and its staff, and then choose an appropriate device. There is no “holy grail” for selecting what instrument is best for a specific office. Rather, it requires time and effort to make a good choice. Carefully assess the instrument before purchase and, ideally, compare several instruments. Once an instrument is purchased and it arrives, carefully validate it before reporting results.

Proper training of the technicians who perform the testing is perhaps the most important factor in obtaining good spirometric testing. After adequate training, it is also important to have continued competency assessments, periodic inservices, and careful review of test results.

The ATS and American Association for Respiratory Care (AARC) published extensive guidelines on the performance of spirometry. These recommendations should be followed to ensure quality and reduce interlaboratory variability. Patients should be properly prepared, the instrumentation properly calibrated, and the test conducted so that there is a good start, adequate exhalation time, satisfactory end-of-test, and good reproducibility between trials.     

Diagnosis of heart failure in primary care

Heart failure is becoming an increasing concern to healthcare worldwide. It is the only cardiovascular disorder that continues to increase in both prevalence and incidence, and as the population continues to age, it is expected that the prevalence of this disease will continue to rise. Guidelines on diagnosis and treatment of heart failure are to be met. Most patients with heart failure will present themselves in general practice. Therefore, the community management of heart failure has become increasingly important and the role of General Practitioners even more crucial. Improving the reliability of diagnosis in primary care is essential since determining the aetiology and stage of heart failure leads to different management choices to improve symptoms, quality of life and disease prognosis. Furthermore, early diagnosis is needed, when there may be no symptoms, since treatment can delay or reverse disease progression. Diagnostic methods may therefore need to encompass screening strategies, as well as symptomatic case identification, in the future. General Practitioners must make correct decisions regarding appropriate further investigation, treatment and referral. A correct diagnosis is the cornerstone leading to effective management. The aim of this paper is to review the role of symptoms and signs and diagnostic tests, such as, chest X-ray, ECG, natriuretic peptides and echocardiography, for diagnosing heart failure in the primary care setting. Improving diagnostic skills remains a continuous challenge for clinicians. Simple and reliable diagnostic procedures are crucial to comply with Guidelines and reduce healthcare utilisation and costs.     

Impact of diabetes education teams in primary care on processes of care indicators

AimsTo evaluate the impact of the integration of onsite diabetes education teams in primary care on processes of care indicators according to practice guidelines.MethodsTeams of nurse and dietitian educators delivered individualized self-management education counseling in 11 Ontario primary care sites. Of the 771 adult patients with HbA1c ≥7% who were recruited in a prospective cohort study, 487 patients attended appointments with the education teams, while the remaining 284 patients did not (usual care group). Baseline demographic, clinical information, and patient care processes (diabetes medical visit, HbA1c test, lipid profile, estimated glomerular filtration rate, and albumin-to-creatinine ratio, measuring blood pressure, performing foot exams, provision of flu vaccine, and referral for dilated retinal exam) were collected from patient charts one year before (pre period) and after (post period) the integration began. A multi-level random effects model was used to analyze the effect of group and period on whether the process indicators were met based on practice guidelines.ResultsCompared to the usual care group, patients seen by the education teams had significant improvements on indicators for semi-annual medical visit and annual foot exam. No significant improvements were found for other process of care indicators.ConclusionsOnsite education teams in primary care settings can potentially improve diabetes management as shown in two process of care indicators: medical visits and foot exams. The results support the benefits of having education teams in primary care settings to increase adherence to practice guidelines.     

Suspected very early inflammatory rheumatic diseases in primary care

As primary care clinicians are typically the first point of contact for patients with musculoskeletal problems, they are crucial to the early diagnosis and treatment of patients with an incident inflammatory arthritis, like rheumatoid arthritis. Current UK and international guidelines recognise this, recommending the prompt referral of patients with suspected persistent synovitis to secondary care. In England and Wales, this is advised to occur within 3 working days. However, recent audit data suggests this recommendation is infrequently met, with some patients waiting many months for referral. In this review article we will discuss the various challenges to achieving the early referral of patients with a new-onset inflammatory arthritis from primary to secondary care. We will also describe how these challenges could potentially be overcome, with the ultimate goal of ensuring that the right patients are referred to the right services, and at the right time.     

Health care utilization and the proportion of primary care physicians

Background

The impact of primary care physicians on health care utilization remains controversial. Some have hypothesized that primary care physicians decrease health care utilization through enhanced coordination of care and a preventive care focus.

Methods

Using data from the Area Resource File (a Health Resources and Services Administration US county-level database) for the years 1990, 1995, and 1999, we performed a retrospective cross-sectional analysis with generalized estimating equations to determine if measures of health care utilization (inpatient admissions, outpatient visits, emergency department visits, and surgeries) were associated with the proportion of primary care physicians to total physicians within metropolitan statistical areas.

Results

The average proportion of primary care physicians in each metropolitan statistical area was 0.34 (SD 0.46, range 0.20-0.54). Higher proportions of primary care physicians were associated with significantly decreased utilization, with each 1% increase in proportion of primary care physicians associated with decreased yearly utilization for an average-sized metropolitan statistical area of 503 admissions, 2968 emergency department visits, and 512 surgeries (all P <.03). These relationships were consistent each year studied.

Conclusions

Increased proportions of primary care physicians appear to be associated with significant decreases in measures of health care utilization across the 1990s. National efforts aimed at limiting health care utilization may benefit from focusing on the proportion of primary care physicians relative to specialists in this country.     

Defining COPD exacerbations: impact on estimation of incidence and burden in primary care

Aims

To investigate the impact of definition on the incidence of chronic obstructive pulmonary disease (COPD) exacerbations in primary care.

Methods

In a one-year prospective, observational study, data from diary cards were used to determine the incidence of symptom- and healthcare-defined exacerbations. One hundred and twenty seven patients completed ≥80% of days in the diary card and were included in the analysis.

Results

Incidence of COPD exacerbation varied according to definition. Mean yearly rates were 2.3 for symptom- and 2.8 for healthcare-defined exacerbations. Although patients with FEV₁ < 50% had a higher mean yearly rate of healthcare-defined exacerbations than those with FEV₁ ≥ 50% (3.2 vs 2.3; p = 0.003), patients with less severe disease reported recurrent exacerbations. There was limited agreement between symptom- and healthcare-defined exacerbations.

Conclusion

Lung function does not appear to be a valid criterion for assigning COPD management directed at patients with recurrent exacerbation.     

Prolonging the return visit interval in primary care

PURPOSE: Extending the scheduled return visit interval has been suggested as one means to improve clinic access to the provider. However, prolonging the return visit interval may affect quality of care if prevention measures and chronic disease management receive less attention as clinic visits become less frequent. The purpose of this study was to determine whether a comprehensive education program could encourage providers to lengthen their return visit interval without compromising performance on key quality indicators. SUBJECTS AND METHODS: This was a prospective cohort study monitoring scheduling and performance data of primary care providers at the Milwaukee Veterans Affairs Medical Center. Following collection of baseline data (January through June 1999), providers were encouraged to lengthen the return visit interval while increasing reliance on nurses and other clinic staff for interim management of chronic disease. Provider-specific feedback of return visit interval and performance data was utilized to motivate behavioral change. Scheduling and clinical data were abstracted from random medical record audits performed at baseline and from July through December in the years 2000 and 2001. RESULTS: Compared with the baseline period, the percent of patients scheduled > or =6 months was significantly increased among staff providers and medicine residents at 2 years (Staff providers: 31% vs. 62%, P <0.001; Medicine residents: 22 vs. 44%, P <0.001). Colorectal screening, pneumonia immunizations, and achievement of therapeutic goals for diabetes, hypertension, and lipid disorders significantly improved at 2 years compared with baseline measurements. CONCLUSIONS: Educational interventions can successfully retrain providers to extend the return visit interval and reduce the scheduling of routine and perhaps unnecessary appointments. This can be accomplished without compromising important performance monitors for diabetes, lipid disorders, hypertension, and prevention.