Depression in an adult Norwegian population: prevalence and associated factors in the Tromsø Study 7

Abstract

Introduction: The burden of depression is considerable worldwide as it is one of the leading causes of disability. People with depression can experience symptoms like loss of interest, feeling sad or depressed, feeling worthless, unnecessary guilt, suicidal thoughts, fatigue, and decreased pleasure. Depression can affect the personal, social, and work life of people as well as may lead to self-harm and suicide. The prevalence of depression may vary with various associated factors. The main purpose of this study was to estimate the prevalence of depression in an adult population and to investigate the associated factors. Materials and methods: A cross-sectional study design was used. Data was extracted from the seventh survey of Tromsø study (Tromsø 7) where 21,038 participants of age 40-90 participated. A total of 20,588 participants with valid symptom checklist (SCL-10) score were included in the analysis. The descriptive statistics were used to describe the characteristics of population and to calculate the distribution of depression among co-variables. The chi square test of independence was used to test whether there was statistically significant relationship between depression and each covariables. The association between depression and covariables was assessed using logistic regression analysis. Results: Among 20588 participants, 11.4% of participants were depressed. The prevalence of depression was 14.0% for female and 8.0% for male. The prevalence of depression varied significantly with age, marital status, household income and chronic pain. Factors like male gender (OR= 0.59, 95% CI:0.53 – 0.64), being married [male: (OR= 0.54, 95% CI: 0.47-0.63), female: (OR= 0.74, 95% CI:0.66-0.83)] , having household income more than 1000000NOK per year [male: (OR= 0.39, 95% CI:0.32-0.48), female: (OR=0.45, 95% CI: 0.38-0.54)] were associated with lower chance of depression. Conclusion: Factors such as age, sex, marital status, household income, chronic diseases, chronic pain, BMI, alcohol consumption, physical activity were associated with depression. The odds of having depression were higher among female, people who were living alone, people who had ever experienced chronic medical conditions like diabetes, cancer, asthma and chronic pain, people with lower low income and people who exercise rarely.