Martti Karvonen

Abstract

Exercise physiologist and pioneer of studies of cardiovascular disease epidemiology in Finland. Born on June 28, 1918, in Nurmes, eastern Finland, he died on March 10, 2009, aged 90 years. Martti Karvonen's childhood years were spent in North Karelia, a rugged, easterly part of Finland where most men carved their livings as farmers or lumberjacks in the region's fields and forests. By the time Karvonen had earned his medical degree from the University of Helsinki in 1945, and a PhD from the University of Cambridge in the UK in 1950, it was clear something was wrong: despite their active lifestyles, North Karelia's men were dying of heart disease. An exercise physiologist, Karvonen began to study these men's calorie consumption. He found that many consumed a staggering 6000 calories daily just to get through their day's work. “You can't manage that by eating potatoes”, notes Karvonen's colleague Kalevi Pyörälä from Kuopio University Hospital, Kuopio, Finland. “You need to eat fat—pork fat, butter on bread, salted meat, salted fish.” In the wake of World War II, heart disease had become a major problem across Finland, as people lapped up the luxuries war had denied them. But the most extreme problems were among the men of the country's eastern region. In the mid 1950s, Karvonen brought this situation to the attention of US researcher Ancel Keys who was trying to identify populations around the world that differed in heart-disease risk. “He convinced Ancel Keys that Finland held a major key to central questions of cardiovascular science and public health at mid-20th century: the causes of cultural differences in heart attack rates and the role of diet in atherosclerosis”, recalls Henry Blackburn, formerly of the University of Minnesota. Together, they published results showing that serum cholesterol concentrations in the east of the country were much higher than in the west. (Lancet 1958; 272: 175–78). These exploratory studies led to Finland participating in Keys' landmark Seven Countries Study. Karvonen and others also started a 12-year study that showed blood cholesterol concentrations and coronary incidence could be reduced with dietary intervention. “He was quite young during this”, says Pyörälä. “He was a man full of ideas, who really pursued things. He got a group of young people in Finland to work with him. He was such a good leader—kind and encouraging. He really was a visionary.” “He was a true father of cardiovascular disease epidemiology and prevention. His comfort in many disciplines and across scientific methods was central to his grasp of and fruitful researches in public health…Countless useful studies and careers, past and present, are due to his ideas and his direct and behind-scenes action”, explains Blackburn. An example of this background activity was Karvonen's central role in the 1972 North Karelia Project, a comprehensive community-based programme for prevention of cardiovascular disease. The project's first impetus came in the form of a petition written by the province's political and health-care leaders, with the help of Karvonen. He was too modest to put himself up for a major role, so he remained “a backstage father” for the project, explains Pyörälä. Instead, at his urging, the leadership of the project was given to another visionary young researcher Pekka Puska, who has since gone on to head Finland's National Public Health Institute. The new project generated much publicity, and is credited with triggering lifestyle changes across the country. Finland's population mean serum cholesterol concentration has since dropped from almost 7 mmol/L in 1972 to about 5·5 mmol/L. Blood pressure and smoking rates among men have also fallen, while mortality from coronary heart disease and stroke has declined by about 80%. “This remarkable chain of events would not have occurred without pioneering work initiated by Martti Karvonen”, says Pyörälä. Karvonen became Director of the Department of Physiology at the Finnish Institute of Occupational Health, Helsinki, rising to become Director General of that Institute. He served as Chief Physician of the Finnish Air Forces for 1956–66, and from 1974 to 1978 as Chief Physician of the Finnish Army. After retirement as Major General he was Visiting Professor at the University of Dortmund, Germany, and Consultant to WHO's Cardiovascular Disease Unit. Karvonen's wife, Annikki, died shortly after him; they had three sons, two daughters, and many grandchildren.