Socio-economic differences in living habits and risk factors in Tromsø municipality

This study can be helpful in prioritizing prevention strategies and health-promoting measures focusing on areas with low area-level socio-economic status.

Background: Norway, an advanced welfare country, is challenged by large social differences in health. Cardiovascular disease (CVD) is one of the leading causes of morbidity and early mortality and vary according to place of residence, level of education, income and living conditions. A public health report from the seventh data collection of the Tromsø Study (Tromsø7, 2015-16) described differences in risk factors across residential areas in Tromsø municipality. We aimed to find the association between area-level socio-economic status (ASES), lifestyle, and CVD risk factors.

Method: We obtained data on individual socio-economic status (SES; education, income, house ownership) and geographical subdivision of Tromsø municipality (36 areas) from Statistics Norway. The variable ASES was created by aggregating individual-level SES variables at the geographical subdivision level. ASES was thereafter ranked and grouped into four groups according to quartiles. We obtained data on individual lifestyle (smoking, snuff, alcohol, physical activity, diet) and risk factors for CVD (body mass index (BMI), total/ high-density lipoprotein cholesterol ratio, waist circumference, hypertension, and diabetes) from Tromsø7 (19,415 participants over 40 years in Tromsø municipality).

Result: ASES was significantly associated with lifestyle and CVD risk factors. People living in area with low ASES have a higher tendency of smoking, physical inactivity, unhealthy diet, and harmful alcohol use. Similarly, those living in area with low ASES have higher BMI and higher cholesterol regardless of their individual-SES. People who live in an area with a higher ASES have lower risk of diabetes (32% women; 17% men) and lower risk of hypertension (21% women; 9% men) than those who live in areas with a lower ASES, regardless of individual SES.

Conclusion: ASES is associated with lifestyle and CVD risk factors regardless of individual-level SES. Residents in lower ASES areas are more likely to have a lifestyle which may contribute to elevated CVD risk factors and development of disease.