Spirometric studies on the adult general population of Helsinki : bronchodilation responses, determinants, and intrasession repeatability of FEV1, FEV6, FVC, and forced expiratory time

Spirometry is the most widely used lung function test in the world. It is fundamental in diagnostic and functional evaluation of various pulmonary diseases. In the studies described in this thesis, the spirometric assessment of reversibility of bronchial obstruction, its determinants, and variation features are described in a general population sample from Helsinki, Finland. This study is a part of the FinEsS study, which is a collaborative study of clinical epidemiology of respiratory health between Finland (Fin), Estonia (Es), and Sweden (S). Asthma and chronic obstructive pulmonary disease (COPD) constitute the two major obstructive airways diseases. The prevalence of asthma has increased, with around 6% of the population in Helsinki reporting physician-diagnosed asthma. The main cause of COPD is smoking with changes in smoking habits in the population affecting its prevalence with a delay. Whereas airway obstruction in asthma is by definition reversible, COPD is characterized by fixed obstruction. Cough and sputum production, the first symptoms of COPD, are often misinterpreted for smokers cough and not recognized as first signs of a chronic illness. Therefore COPD is widely underdiagnosed. More extensive use of spirometry in primary care is advocated to focus smoking cessation interventions on populations at risk. The use of forced expiratory volume in six seconds (FEV6) instead of forced vital capacity (FVC) has been suggested to enable office spirometry to be used in earlier detection of airflow limitation. Despite being a widely accepted standard method of assessment of lung function, the methodology and interpretation of spirometry are constantly developing. In 2005, the ATS/ERS Task Force issued a joint statement which endorsed the 12% and 200 ml thresholds for significant change in forced expiratory volume in one second (FEV1) or FVC during bronchodilation testing, but included the notion that in cases where only FVC improves it should be verified that this is not caused by a longer exhalation time in post-bronchodilator spirometry. This elicited new interest in the assessment of forced expiratory time (FET), a spirometric variable not usually reported or used in assessment. In this population sample, we examined FET and found it to be on average 10.7 (SD 4.3) s and to increase with ageing and airflow limitation in spirometry. The intrasession repeatability of FET was the poorest of the spirometric variables assessed. Based on the intrasession repeatability, a limit for significant change of 3 s was suggested for FET during bronchodilation testing. FEV6 was found to perform equally well as FVC in the population and in a subgroup of subjects with airways obstruction. In the bronchodilation test, decreases were frequently observed in FEV1 and particularly in FVC. The limit of significant increase based on the 95th percentile of the population sample was 9% for FEV1 and 6% for FEV6 and FVC; these are slightly lower than the current limits for single bronchodilation tests (ATS/ERS guidelines). FEV6 was proven as a valid alternative to FVC also in the bronchodilation test and would remove the need to control duration of exhalation during the spirometric bronchodilation test.Astma ja keuhkoahtaumatauti (COPD) ovat kansansairauksia, joiden diagnostiikassa virtaus-tilavuusspirometria on keskeisessä asemassa. Astmassa keuhkoputkien ahtautuminen on vaihtelevaa ja palautuvaa, joko spontaanisti tai keuhkoputkiin vaikuttavien lääkeaineiden seurauksena. Keuhkoahtaumatauti on pääasiassa tupakan savusta johtuva keuhkoputkia ahtauttava sairaus, jossa keuhkoputkien muutokset ovat pysyviä. Keuhkoahtaumatauti on usein alidiagnosoitu sairaus. Taudin varhaisia oireita pidetään usein vaarattomina ja ohimenevinä. Kansainvälisten kriteerien mukaisesti diagnoosi perustuu spirometrialöydökseen, jossa todetaan keuhkoputkien ahtautumisesta johtuva ilman virtausnopeuden ja keuhkotilavuuksien pienentyminen; tosiasiassa tauti on kuitenkin monivivahteisempi. Osalla potilaista keuhkorakkuloiden tuhoutuminen johtaa keuhkon laajentumaan (emfyseemaan) ja toisilla potilailla taudinkuvaa hallitsee krooninen keuhkoputkitulehdus. Keuhkoahtaumatautia sairastaa noin 10% väestöstä ja lääkärin toteama astma on aikaisempien tulosten perusteella noin 6%:lla helsinkiläisistä aikuisista. Väitöstutkimus liittyy yhteispohjoismaiseen FinEsS-tutkimukseen, jossa tutkitaan hengityssairauksien esiintyvyyttä Suomessa (Fin), Virossa (Es) ja Ruotsissa (S). Tutkimusaineisto perustuu vuonna 1996 Helsingistä valittuun 8000 henkilön satunnaisotantaan. Näin valituille henkilöille lähetettiin postitse kyselylomake hengityssairauksien oireista. Vastanneista 6062 henkilöstä valittiin vuonna 2000 edelleen 1200 henkilöä kliinisiin tutkimuksiin, joihin osallistui 643 henkilöä vuosina 2001-2003. Tässä väitöstutkimuksessa tutkittiin virtaus-tilavuusspirometrialla mitattujen keuhkofunktiomuuttujien vaihtelua sekä bronkodilaatiovastetta väestössä. Virtaus-tilavuusspirometrian tärkeimpien mittaussuureiden todettiin tutkimuksessa olevan hyvin toistettavia mittauskerran aikana. Sen sijaan puhallusaika (FET) vaihteli muita mittaussuureita enemmän myös terveillä aikuisilla. Puhallusajan todettiin olevan noin 10 sekuntia ja pitenevän ikääntyessä ja keuhkoputkien ahtauman lisääntyessä. Keuhkoputkia laajentavan lääkityksen seurauksena sekuntikapasiteetin (FEV1) paraneminen oli väestötasolla vähäisempää kuin aikaisempien tutkimusten perusteella on oletettu. Väestötasolla FEV1- arvon paraneminen yli 9% lähtötasosta oli tilastollisesti merkitsevää. Nopean vitaalikapasiteetin (FVC) arvot pienenivät vielä yleisemmin erityisesti terveillä tupakoimattomilla aikuisilla; merkitsevän muutoksen raja oli 6% lähtötasosta. Kuuden sekunnin sekuntikapasiteetin (FEV6) on katsottu voivan korvata FVC:n seulontatutkimuksissa ja avoterveydenhuollossa. Tässä tutkimuksessa vahvistui käsitys, että FEV6 voisi korvata FVC:n seulontatutkimuksissa, jolloin tarve säädellä puhallusaikaa bronkodilaatiokokeen aikana poistuu. FEV6:n käytön yleistymistä rajoittavat kuitenkin toistaiseksi vielä suomalaisten viitearvojen puute. FEV1:n bronkodilataatiovaste väestössä oli odotettua vähäisempi; tulos viittaisi siihen suuntaan, että käytössä olevia FEV1:n merkitsevän muutoksen rajoja olisi ehkä syytä tarkistaa

No change in prevalence of symptoms of COPD between 1996 and 2006 in Finnish adults : a report from the FinEsS Helsinki Study

Background: The age-dependent increase of chronic obstructive pulmonary disease (COPD) prevalence caused by smoking and other inhalational exposures in the general population is well-known worldwide. However, time trends are poorly known, due to lower number of high-quality studies especially following nationwide efforts on diminishing exposure levels. This study aimed to compare the prevalence of COPD symptoms and their major determinants in Finnish adults in 1996 and 2006. Methods: Two identical postal surveys were conducted among two random population samples from Helsinki using identical methodologies in 1996 and 2006, with 6,062 (76%) and 2,449 (62%) participants, respectively. Results: The physician-diagnoses of COPD remained at 3.7%, whereas physician-diagnoses of asthma and use of asthma medicines increased in both genders. Current smoking reduced from 33.4 to 27.3% (p<0.001), and the amount of cigarettes smoked also reduced significantly. The crude prevalence of chronic productive cough was 12.1 and 11.1%, wheezing with dyspnoea without a cold (wheezing triad) 7.3 and 7.7%, and dyspnoea grade II 13.8 and 13.6%, in 1996 and 2006, respectively. Among subjects with physician-diagnosed COPD, the prevalences of chronic productive cough and recurrent wheeze reduced significantly, from 60.6 to 40.7% and 53.5 to 38.5%, respectively. Conclusion: From 1996 to 2006, the prevalence of obstructive airway symptoms common in different phenotypes of COPD did not increase in Finnish adults. This suggests that the upward trend of COPD prevalence might have reached a plateau. Current smoking and the quantities smoked diminished suggesting a wider impact of stronger legislation and smoking-cessation efforts during the Finnish National Programme for COPD.Peer reviewe

Keski-ikäisen naisen hengenahdistusoire

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GOLD criteria overestimate airflow limitation in one-third of cases in the general Finnish population

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Prevalence of abnormal findings when adopting new national and international Global Lung Function Initiative reference values for spirometry in the Finnish general population

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Responses of FEV6, FVC, and FET to inhaled bronchodilator in the adult general population

<p>Abstract</p> <p>Background</p> <p>The assessment of bronchodilator-induced change in forced vital capacity (FVC) is dependent on forced expiratory time (FET) in subjects with airflow limitation. Limited information is available on the concurrent responses of FVC, forced expiratory volume in six seconds (FEV₆), and FET in the bronchodilation test among patients with obstructive airways disease or in the general population. The aim of this study was to assess the changes in FEV₆, FVC, and FET, and their relationships in a standardized bronchodilation test in the general population.</p> <p>Methods</p> <p>We studied bronchodilation response in a general adult population sample of 628 individuals (260 men, 368 women) with flow-volume spirometry. The largest FVC, the corresponding FET and the largest FEV₆both at the baseline and after 0.4 mg of inhaled salbutamol were selected for analysis.</p> <p>Results</p> <p>After administration of salbutamol FEV₆decreased on average -13.4 (95% CI -22.3 to -4.5) ml or -0.2% (-0.4% to 0.0%) from the baseline. The 95^thpercentile of change in FEV₆was 169.1 ml and 5.0%. FVC decreased on average -42.8 (-52.4 to -33.3) ml or -1.0% (-1.2% to -0.7%). Concurrently FET changed on average -0.2 (-0.4 to 0.0) seconds or 0.4% (-1.4% to 2.3%). There were four subjects with an increase of FVC over 12% and only one of these was associated with prolonged FET after salbutamol. Changes in FEV₆and FVC were more frequently positive in subjects with reduced FEV₁/FVC in baseline spirometry.</p> <p>Conclusion</p> <p>In general adult population, both FEV₆and FVC tended to decrease, but FET remained almost unchanged, in the bronchodilation test. However, those subjects with signs of airflow limitation at the baseline showed frequently some increase of FEV₆and FVC in the bronchodilation test without change in FET. We suggest that FEV₆could be used in assessment of bronchodilation response in lieu of FVC removing the need for regulation of FET during bronchodilation testing.</p

Reference values of inspiratory spirometry for Finnish adults

Inspiratory spirometry is used in evaluation of upper airway disorders e.g. fixed or variable obstruction. There are, however, very few published data on normal values for inspiratory spirometry. The main aim of this study was to produce reference values for inspiratory spirometry for healthy Finnish adults.Inspiratory spirometry was preplanned to a sample of the Finnish spirometry reference values sample. Data was successfully retrieved from 368 healthy nonsmoking adults (132 males) between 19 and 83years of age. Reference equations were produced for forced inspiratory vital capacity (FIVC), forced inspiratory volume in one second (FIV1), FIV1/FIVC, peak inspiratory flow (PIF) and the ratios of FIV1/forced expiratory volume in one second and PIF/peak expiratory flow. The present values were compared to PIF values from previously used Finnish study of Viljanen etal. (1982) reference values and Norwegian values for FIV1, FIVC and FIV1/FIVC presented by Gulsvik etal. (2001). The predicted values from the Gulsvik etal. (2001), provided a good fit for FIVC, but smaller values for FIV1 with mean 108.3 and 109.1% of predicted values for males and females, respectively. PIF values were 87.4 and 91.2% of Viljanen etal. (1982) predicted values in males and females, respectively. Differences in measurement methods and selection of results may contribute to the observed differences. Inspiratory spirometry is technically more demanding and needs repeatability criteria to improve validity. New reference values are suggested to clinical use in Finland when assessing inspiratory spirometry. Utility of inspiratory to expiratory values indices in assessment of airway collapse need further study.Peer reviewe

COPD in Helsinki, Finland: socioeconomic status based on occupation has an important impact on prevalence

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Validation of the Finnish Severe Respiratory Insufficiency Questionnaire

Abstract Introduction Chronic respiratory insufficiency impacts patients? lives and reduces quality of life. The Severe Respiratory Insufficiency (SRI) questionnaire examines health-related quality of life and is designed specifically for patients receiving home mechanical ventilation (HMV) for chronic respiratory failure (CRF). Objectives The aim of this study was to validate the Finnish version of the SRI and study its reproducibility in patients with CRF. Methods Our 74 patients receiving HMV or long-term oxygen treatment for CRF or both completed the SRI and St George?s Respiratory questionnaires (SGRQ) three times (at baseline, and then one week and one month later). Reliability and validity of the questionnaires was analyzed with Cronbach?s alpha and intraclass correlation coefficient. Patients were prospectively followed-up for five years, with data collected on their use of hospital services and mortality. Results Cronbach?s alpha in the SRI ranged from 0.67 to 0.88 and was >0.7 on all subscales except the ?attendant symptoms and sleep?. On four subscales, Cronbach?s alpha was >0.8, and on the summary scale, 0.95. The SRI showed high correlation with SGRQ. Both tests showed good reproducibility. During the five-year follow-up, 27 (36%) patients died. Conclusions The Finnish SRI proved valid, reliable, and reproducible. Its psychometric properties were good and similar to those of the original questionnaire and of other validation studies.Peer reviewe