Respiratory symptoms and long-term risk of death from cardiovascular disease, cancer and other causes in Swedish men

Abstract

Background: Depressed respiratory function and respiratory symptoms are associated with impaired survival. The present study was undertaken to assess the relation between respiratory symptoms and mortality from cardiovascular causes, cancer and all causes in a large population of middle-aged men.

Methods: Prospective population study of 6442 men aged 51-59 at baseline, free of clinical angina pectoris and prior myocardial infarction.

Results: During 16 years there were 1804 deaths (786 from cardiovascular disease, 608 from cancer, 103 from pulmonary disease and 307 from any other cause). Men with effort-related breathlessness had increased risk of dying from all of the examined diseases. After adjustment for age, smoking habit and other risk factors, the relative risk (RR) associated with breathlessness of dying from coronary disease was 1.43 (95% CI : 1.16-1.77), from stroke 1.77 (95% CI: 1.07-2.93), from any cardiovascular disease 1.48 (95% CI : 1.24-1.76), cancer 1.36 (95% CI : 1.11-1.67) and from any cause 1.62 (95% CI: 1.44-1.81). An independent effect of breathlessness on cardiovascular death, cancer death and mortality from all causes was found in life-time non-smokers, and also if men with chest pain not considered to be angina were excluded. An independent effect was also found if all deaths during the first half of the follow-up were excluded. Men with cough and phlegm, without breathlessness, also had an elevated risk of dying from cardiovascular disease and cancer, but after adjustment for smoking and other risk factors this was no longer significant. However, a slightly elevated independent risk of dying from any cause was found (RR = 1.18 [95% CI: 1.02-1.36]).

Conclusion: A positive response to a simple question about effort related breathlessness predicted subsequent mortality from several causes during a follow-up period of 16 years, independently of smoking and other risk factors.