The project is based on combined analyses of nine cohorts from Denmark and Sweden:
The inclusion criteria for the Danish Diet Cancer and Health (DCH) cohort were age between 50 and 64 y, residing in the greater Copenhagen or Aarhus area and without a cancer diagnosis. From 1993 to 1997, 160,725 Danes were invited to participate of whom 57,053 participants accepted the invitation and were enrolled in the study. All participants completed detailed questionnaires at enrolment and trained staff members measured height, weight, and waist circumference.
The Danish Nurse Cohort (DNC) was initiated by sending questionnaires to the members of the Danish Nurse Organization in 1993 and 1999. Among 33,704 eligible female nurses aged 44-93 years who either worked or were retired in 1993 or 1999, 28,731 participants (85·2%) were included in the DNC. Upon enrolment, participants answered a comprehensive questionnaire on body mass index (BMI), lifestyle factors (smoking, alcohol consumption, physical activity, and dietary habits), self-reported diseases and reproductive health, and working conditions.
The Stockholm Diabetes Preventive Programme (SDPP) is a prospective cohort aimed at investigating the aetiology of type 2 diabetes and cardiometabolic risk factors. The cohort comprises 34 486 men and women aged 35-56 years who lived in five municipalities in Stockholm County 1992-1998. A sub-sample of 7,949 individuals were invited to a clinical examination at baseline and were followed up 2002-2006 and 2014-2017. During the clinical examinations, blood pressure was measured along with anthropometric measurements, blood samples were collected, oral glucose tolerance tests were administered, and participants answered extensive questionnaires concerning lifestyle factors, health status, socioeconomic characteristics, and psychosocial conditions.
The SIXTY cohort is based on a random sample of every third man and woman living in Stockholm County, who were born in 1937 and 1938. A total of 4,232 subjects were recruited 1997-1999 to investigate risk factors for cardiovascular disease. People were 59- 61 years at enrolment. Measurements of anthropometric indices and blood pressure were made at recruitment and fasting blood samples were collected. In addition, a comprehensive questionnaire was completed, including information on socioeconomic, medical and lifestyle factors.
The Screening Across the Lifespan Twin Study (SALT) included a total of about 45 000 twins born 1958 and earlier from the Swedish Twin Registry who were interviewed 1998-2002. Those 7,043 who resided in Stockholm County at recruitment are included in the present project. People were 42-97 years at enrolment. The interview collected data on zygosity, diseases, use of medication, occupation, education and lifestyle habits. In a subgroup of around 2,500 subjects, a clinical examination was made, including blood sampling and anthropometrics as well as blood pressure measurements
The Swedish National Study of Aging and Care in Kungsholmen (SNAC-K) was established 2001-2004 and included 3,363 residents aged 60-104 years in Kungsholmen, Stockholm. The aim was to investigate the ageing process and identify possible preventive strategies to improve health and care in elderly adults. Information was collected through social interviews and clinical examinations, including assessment of physical and cognitive functioning. Follow-up investigations are performed at intervals of three to six years depending on age
The Malmö Diet and Cancer (MDC) study is a population based prospective cohort study. People were enrolled into the cohort between 1991 and 1996, and eligible participants were men born between 1923 and 1945 and women born between 1923 and 1950, living in the city of Malmö. Swedish reading and writing skills were required. People were 44-73 years at enrolment. The data collection was done both using questionnaires and interviews, including data on dietary habits, socio-economics, medical history and lifestyle factors. The total number of study subjects was 28,098.
The Swedish Mammography Cohort is a population-based prospective cohort study established 1987-90 when all 90,303 women living in Uppsala and Västmanland counties, born 1914-48, were invited to a mammography screening and to respond to a questionnaire (74% response rate). In 1997, the 56,030 participants who were still living in the study area were invited to respond to a second extended questionnaire, (response rate 70 %). In the present project, we included the women from Uppsala County taking part in the 1997 investigation (n= 20,407).
The Danish National Health Survey (DNHS) included 177 639 persons aged 16 years and older randomly selected across Denmark who answered a questionnaire in 2010 or 2013.40 Information on age, sex, education and labor market affiliation was obtained from national registers. The questionnaire focused on sex, age, cohabiting status, education, occupation, smoking, alcohol consumption, diet, physical activity and anthropometric data
For all cohorts exclusion criteria included illness and insufficient knowledge of Danish or Swedish, making it difficult to answer questionnaires and/or participate in clinical investigattions.
