Conflict of interest
1 / 33

Conflict of Interest - PowerPoint PPT Presentation

  • Uploaded on

Conflict of Interest. Actelion, Bohringer-Ingelheim, Bayer (Congress support and study). LFT parameters used in COPD diagnosis and their role in clinical practice: Lower Limit of Normal. Esen KIYAN, MD İ.Ü. İstanbul Medical Faculty Department of Respiratory Diseases.

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
Download Presentation

PowerPoint Slideshow about 'Conflict of Interest' - toan

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
Conflict of interest

Conflict of Interest

Actelion, Bohringer-Ingelheim, Bayer (Congress support and study)

Lft parameters used in copd diagnosis and their role in clinical practice lower limit of normal

LFT parameters used in COPD diagnosis and their role in clinical practice: Lower Limit of Normal


İ.Ü. İstanbul Medical Faculty

Department of Respiratory Diseases

Conflict of interest

LLN: statistical definition clinical practice:

Below 5th percentile of reference population (false negative rate %5)

Fev1 fev1 fvc depends on age gender height and race
FEV1, FEV1/FVC depends on age, gender, height and race. clinical practice:

Hankinson JL, AJRCCM 1999

Conflict of interest

Falaschetti ERJ 2004 clinical practice:

174cm, male

Pred. mean


165cm, female

Fixed ratio fits all
Fixed ratio fits all clinical practice:

In healty people, decrease in FEV1 with age is bigger than decrease in FVC. This causes decrease in FEV1/FVC ratio by age.

Age>45, LLN for FEV1/FVC<0.70

(Falaschetti E, ERJ 2004; Stanojevic S, AJRCCM;2008; Stanojevic S, ERJ 2010)


Conflict of interest

Obstruction= FEV1/FVC<LLN (<5th percentile of predicted value, 5th percentile of healthy population)

LLN=predicted value – (1.645*SD)

Conflict of interest

Usin the lower limit of normal for the FEV1/FVC ratio reduces the misclassification of airway obstruction. Swanney Thorax 2008

40 646 adult/13 136 asymptomatic and never smoker

American (4630)-Dutch (1204)-British (7302) populations’s pirometry data


COPD prevalence in asymptomaticandneversmokeradults.HSE: HealthSurveyforEngland 1995-96, NL: Hollanda verisi, NHANES: NationalHelathandNutritionExaminationSurvey (beyaz ırk için Amerika verisi)


LLN for FEV1/FVC decreases in healthy population with age (in man 57, in women 55 prediction equations)

Conflict of interest

COPD prevalence in men and women according to GOLD and LLN definition

False COPD diagnosis in healthy adults over 60 years: %17-45 in men, %7-26 in women

Swanney Thorax 2008

Conflict of interest

Fixed raio causes high (50%) false positive diagnosis in adults ≥45

Hardie JA, ERJ 2002; Celli BR, ERJ 2003; Roberts SD, Chest 2006; Vollmer WM, ERJ 2009; Swanney MP, Thorax 2008; Ko FWS, ERJ 2008; Schermer TR, ERJ 2008; Miller MR, Chesy 2010; Vaz Fragoso CA, AJRCCM 2010

Conflict of interest

FEV1/FVC and FEV1 pred values (Falaschetti adults ≥45et al.)

1995-1996 Health Surveys for England

Nonsmoker men without asthma,

At 47 age, LLN for FEV1/FVC<0.7 line (false positive)

47-49 ages LLN for FEV1>%80 pred (GOLD stage 1/milfd obst.)

Over 50, LLN for<%80 pred (GOLD stage 2/moderate obst.)

Conflict of interest

GOLD0 criteria misses COPD cases in young adults and therefore causes delay in treatment to prevent disease progression

Cerveri 2009: Age<52, true COPD diagnosis with fixed ratio is 77% in women and 57% in men.

Hansen 2007: false negative diagnosis is 50% with fixed ratio

Gold 2006 gold 2010
GOLD 2006 GOLD 2010 therefore causes delay in treatment to prevent disease progression

  • Since progress of aging affect lung volume, use of fixed ratio may result in overdiagnosis of COPD in elderly, and underdiagnosis in young adults (<45year)(Cerveri I, Thorax 2008).

  • Using LLN for FEV1/FVCis one way to minimize potential misclassificaton.

  • If reference equations for LLN available, most of the spirometers do this calculation

  • Howeverreference equations using post BD FEV1 and longitudinal studies to validate the use of LLN are urgently needen.

Factors affecting copd prevalence
Factors affecting COPD prevalence therefore causes delay in treatment to prevent disease progression

  • Criteria used for obstruction? Fixed ratio vs LLN?

  • Postbronchodilator LFT?

    • PostBD causes 30% decrease in COPD prevalence (Johannessen A. Implication of reversibility testing on prevalence and risk factors for chronic obstructive pulmonary disease: a community study. Thorax 2005)

  • Which reference equations used?

  • Conflict of interest

    LLN vs FEV1/FVC<0.70, Which one is correct for COPD diagnosis?

    Hoesein M, et al. Lower limit of normal or FEV1/FVC<0.70 in diagnosing COPD: An evidence-based review. Respir Med 2011.

    MEDLINE, EMBASE, Cochrane data

    Studies between 1966-2010

    Total 1954 studies……………18 evaluated

    Level of evidence (1a/b---expert opinion:5)

    Postbd fev1 fvc lln and postbd fev1 fvc 0 70
    PostBD FEV1/FVC<LLN and postBD FEV1/FVC<0.70 in COPD prevalence.

    • Prevalence and risk factors of airflow obstruction in an elderly Chinese population. Ko FWS, ERJ 2008

      • 1008 people (≥60yaş), LLN prevalence %12.4 vs %25.9

    • COPD prevalence in a random population survey: a matter of definition,Shirtclffe P, ERJ 2007

      • 749 people (≥40 years; 0nly 38.9% was ≥60years), LLN prevalence %9 vs %14.2

    Postbd fev1 fvc 0 70 vs postbd fev1 fvc lln
    PostBD FEV1/FVC<0.70 vs postBD FEV1/FVC<LLN in COPD prevalence.

    • Shirtcliffe P, ERJ 2007 (3500 people/ New Zealand)

    • 749 spirometry/ population based/ over 40 years

    • Postbd LLN prevalence %9.5 (caused 30% decrease in prebd LLN diagnosis) vs %14.2

    • Prebd LLN prevalence %15.2,

    • Doctor diagnosis prevalence %10.5


    Prebd LLN

    Doctor diagnosis

    Postbd LLN

    COPD prevalence according to diagnostic criteria

    Postbd fev1 fvc 0 70 vs postbd fev1 fvc lln1
    PostBD FEV1/FVC<0.70 vs postBD FEV1/FVC<LLN in COPD prevalence.

    • Lamprecht B, Pulmonary Med 2011

      • NHANES III reference equations

      • 1258 correct spirometry

      • Prevalence with fixed raion 24.2%, with LLN 15.3%, doctor diagnosis prevalence 5.6%

    >LLN but <0.70 (in-between obstruction) group had higher comorbidity-especially cardiac.

    Mannino cohort study of cardiovascular health study thorax 2007
    Mannino (Cohort study of Cardiovascular Health Study), Thorax 2007

    • Long-termstudy/mortalityand COPD relatedhospitalisation

    • 4965 cases (>65 years), 11 years of follow-up

    • 1134 cases had FEV1/FVC<0.70 but > LLN

      Mortality (HR 1.3) andhospitalisation (HR 2.6) higherthancaseswith normal spirometry

      Fixedratiomayidentify at-risk patients. Using LLN toclassifylungdisease in olderpeoplemaymiss a part of thepopulationmorelikelytohavecomplications.

    Conflict of interest

    FEV1/FVC LLN Thorax 2007

    Fixed ratio

    GOLD 2-4

    FEV1/FVC LLN, FEV1<%80


    Conflict of interest
    Comparison of spirometry criteria for the diagnosis of COPD: results from the BOLD study. Volmer WM, ERJ 2009

    Fixed ratio

    Ratio LLN

    GOLD 2-4

    LLN and FEV1<%80

    Ratio and FEV1 <LLN

    GOLD 2-4 prevalence


    Local pred equations

    COPD prevalence in never smoker healthy people

    Turkey bold study kocabas a 2006
    Turkey-BOLD study results from the BOLD study. Volmer WM, ERJ 2009(Kocabas A, 2006)

    Conflict of interest

    FEV1/FVC<0.70 disadvantages results from the BOLD study. Volmer WM, ERJ 2009

    • Overdiagnosis in older people

    • Unneccessary treatment(?)……side effects

    • and increase in cost

    • Psychological trauma and decrease in helath quality

    • False positive COPD cases in clinic studies ….false conclusions

    Underdiagnosis in young adults

    Delay in treatment

    Lln i in s k nt lar
    LLN için sıkıntılar results from the BOLD study. Volmer WM, ERJ 2009

    Problems of LLN

    • Needsstatisticalanalysis. New spirometries do this but no print-out.

    • Changesaccordingtoreferenceequations (Countries/ethnicgroupsneeddifferentreferenceequations/if not, usethemostsuitableone

    Conflict of interest

    1995-2004 arası yayınlanan referans denklemleri results from the BOLD study. Volmer WM, ERJ 2009

    White people have at least 30 reference equations for FEV1/FVC LLN

    They must be specific for countries

    Conflict of interest

    There is no statistical evidence for fixed ratio and predicted %

    LLN is an statistical definition and decreases misclassifications.

    Is it true to use GOLD COPD diagnosis criteri?

    Conflict of interest
    SONUÇ predicted %

    • LLN decreases underdiagnosis in young adults and leads to early treatment.

    • LLN decreases overdiagnosis in older people (esp GOLD stage I) and decreases unneccessary treatment and therefore prevents unneccessary treatment-complications and increase in cost.

    • Subjects classified as >LLN but <0.70 are more likely to die and to have COPD related hospitalisation during follow-up. LLN miss these patients (Mannino Thorax 2003).

    • Longitudinal studies using postbronkodilator values are needed.

    Conflict of interest