Prevalence of and factors associated with depression in the hill tribe population aged 40 years and older in northern Thailand

Background Depression is globally recognized as a major mental health problem in all age categories, particularly among those living in poor economic conditions and with low levels of education, including the hill tribe people in northern Thailand. Methods This cross-sectional study aimed to estimate the prevalence of depression and determine the factors associated with depression in the hill tribe population aged 40 and over in northern Thailand. Hill tribe people who lived in the selected villages and met the inclusion criteria were invited to participate in the study. A validated questionnaire and the Patient Health Questionnaire-9 (PHQ-9) were used for data collection. An interview was conducted in a private and confidential room in the selected villages between January and April 2019. Logistic regression was used to determine the factors associated with depression at a significance level of α = 0.05. Results A total of 601 participants were recruited into the study. More than half (64.23%) were women, 46.76% were Akha, 61.90% were aged 40–59 years, and 76.37% were married. Half of the participants were Christian (57.07%) and had no monthly income (51.25%), and 85% were illiterate. The overall prevalence of depression was 39.10%: 75.74% had mild depression, 17.88% had moderate depression, and 6.38% had severe depression. In the multivariate model, three variables were found to be associated with depression: being female, having a history of substance abuse, and experiencing stress six months prior. Compared to men, women were 2.09 times (95% CI 1.30–3.35) more likely to have depression. Those who had a history of substance abuse were more likely to have depression than those who did not have a history of substance abuse (AOR = 1.97; 95% CI 1.25–3.10). Those who had a history of stress in the prior 6 months were more likely to have depression than those who did not (AOR = 6.43; 95% CI 4.20–9.85). Conclusion Public health screening programs to identify depression in the hill tribe population are urgently needed, particularly for women, those who have abused psychoactive substances, and those who have experienced stress.