RISK OF MYOCARDIAL-INFARCTION AMONG SUBJECTS VISITING A DOCTOR BECAUSE OF BACK DISORDER - A CASE-CONTROL STUDY IN FINNISH FARMERS

Study Design. A nested case-control study was made to analyze the corr elation between back trouble and myocardial infarction. Objectives. Th e purpose of the present study was to determine whether individuals vi siting a doctor because of back trouble have an increased risk for myo cardial infarction. Summary of Background Data. According to previous results, back pain precedes myocardial infarction in young and middle- aged male farmers. There are no previous results concerning the risk o f myocardial infarction among patients visiting a doctor because of ba ck pain. Methods. The basic cohort includes 3172 Finnish farmers. Thos e having myocardial infarction from February 1, 1980 through December 31, 1992 were considered case studies. Three matched control subjects were selected for every case subject. The final group had 83 case subj ects and 249 matched control subjects. Case subjects and control subje cts were compared according to doctor visits because of back complaint during the follow-up period, which began February 1, 1980 and ended o n the date of myocardial infarction of each case subject. Results. Few er case subjects than control subjects visited a doctor because of bac k disorders during the follow-up period. This was especially true for nonspecific back pain (odds ratio = 0.51; confidence interval = 0.25-1 .05). Conclusions. Atherosclerosis is not a probable cause of any kind of back pain among individuals visiting a general practitioner becaus e of back complaint.