Audit of secondary prophylaxis after myocardial infarction

possible explanation is that people with chronic back pain tend to retire earlier from physically demanding work.According to former observations the risk of back pain increases until the age of 50 years and then decreases.5To my knowledge, this is the first prospective study on the association between back pain and mortality.More research is needed to determine the validity of these results and to find out the character and mechanism of vascular back pain.If vascular reasons prove to be the usual causes of back pain, the diagnosis and care of chronic back pain will change drastically.This study was supported by the Farmers' Social Insurance Institution of Finland.I thank Pentti Mikela for his data processing work.