The single breath nitrogen test and mortality - A 38 years follow up

• Background: Spirometry data predict mortality, but are less sensitive to detect dysfunction in small airways as compared to the slope of phase III (the N-2 slope) of the single breath nitrogen test. The association between the N-2 slope and mortality has been studied with conflicting results. In the present study the prognostic importance of the N-2 slope was tested taking spirometry variables into account. Methods: A systematic general population sample of 595 middle-aged men had a baseline investigation with lung function tests including spirometry and the N-2 slope. Age, smoking, and anthropometry variables were registered. The cohort was followed up regarding survival for 38 years. Results: The sample was subdivided by tertiles of the N-2 slope. A proportional hazards regression analysis was performed for each group of covariates: anthropometric, smoking variables, and spirometry variables, after accounting for age. Covariates with significant impact on mortality and the highest chi-square levels were smoking habit score and forced expired volume in 1 s corrected for height. These variables, in addition to age and the N-2 tertiles were entered into a final proportional hazards regression analysis. In this multivariate model, mortality was significantly related to age (p < .0001), smoking habit score (p < .0001) and the N-2 tertiles (p = .0004), but not to FEV1 when N-2 slope was allowed for in the model. Conclusions: Dysfunction in small airways as measured by the N-2 slope is significantly associated with overall mortality in middle-aged men, and outrivals spirometry as a predictor in multivariate analysis.

Ämnesord

MEDICIN OCH HÄLSOVETENSKAP  -- Klinisk medicin (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Clinical Medicine (hsv//eng)

MEDICIN OCH HÄLSOVETENSKAP  -- Klinisk medicin -- Lungmedicin och allergi (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Clinical Medicine -- Respiratory Medicine and Allergy (hsv//eng)

MEDICIN OCH HÄLSOVETENSKAP  -- Klinisk medicin -- Kardiologi (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Clinical Medicine -- Cardiac and Cardiovascular Systems (hsv//eng)

Nyckelord

Mortality

Single breath nitrogen test

Spirometry

Smoking

Small airways function

Epidemiology

lung-function

pulmonary-function

small airways

respiratory symptoms

alveolar plateau

closing volume

population

disease

smoking

asthma

Cardiovascular System & Cardiology

Respiratory System

Mortality

Publikations- och innehållstyp

ref (ämneskategori)

art (ämneskategori)