In a recent study published in the American Journal of Preventive Medicine, researchers explored trends in the prevalence of depression from 2015 to 2020.
Study: Trends in the prevalence of depression in the US from 2015 to 2020: The widening treatment gap. Image credit: Mary Long/Shutterstock
The most common mental illness in the United States is major depression, which also carries the highest risk of suicidal behavior. According to early reports in 2020 and beyond, the 2019 coronavirus (COVID-19) pandemic may have contributed to the country’s rising mental health problem, especially among teenagers and young adults. To effectively assess and address the effects of the pandemic on mental health, accurate pre-pandemic national estimates are essential.
About the study
In the present study, researchers calculated the annual prevalence of major depression in the previous 12 months among Americans aged 12 years and older between 2015 and 2020.
The National Survey on Drug Use and Health (NSDUH) provided data for the study. The NSDUH provides annual cross-sectional national data on substance use and mental health in the United States. Data sets from each year between 2015 and 2019 were combined. To account for non-response at the individual level, sample weights were calculated for the person-level analysis and then adjusted to ensure the consistency with population estimates received from the US Census Bureau. The original weight was divided by the total number of data sets to obtain a new weight.
Based on the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) criteria, questions to measure major depressive episodes (MDE) were addressed for adults and adolescents aged 12–17 years. For respondents older than 18 years, the depression modules were adapted from the National Comorbidity Survey-Replication, while those for respondents aged 12-17 years were adapted from the National Comorbidity Survey-Adolescents.
Based on reporting five or more of nine MDE symptoms, including depressed mood, loss of interest or pleasure in daily activities over a two-week period, both adult and adolescent respondents were they classified as lifetime MDE. Those who met the requirements for a lifetime MDE and reported feeling depressed or lost interest in daily activities along with other symptoms for at least two weeks in the previous 12 months were further classified as Last year’s MDE. The adolescent and adult factors were combined to form the past year MDE variable for this research.
Two questions were used to assess help-seeking behavior for depression in the past year. In addition to asking whether they had received prescription medications for their MDD symptoms in the previous 12 months, respondents were also asked whether they had recently consulted or talked to a physician (MD) or other professional about your symptoms
results
After controlling for sociodemographic factors, the prevalence of recent depression increased from 7.3% in 2015 to 8.6% in 2019, and this monotonic increase from 2015 to 2019 persisted. In 2020, 9.2% of people had depression in the previous year.
Stratifying the population by age, the highest prevalence of depression during the study period was found among adolescents aged 12 to 17 years and young adults aged 18 to 25 years. The prevalence of depression increased from 12.7% in 2015 to 15.8% in 2019. and 16.9% in 2020 among teenagers. In addition, the number of patients with depression increased from 10.3% in 2015 to 15.5% in 2019 and 17.2% in 2020 in adults aged 18-25. In addition, depression was reported at 7.5% in 2015, 10.9% in 2019 and 2020 for adults aged 26-34. The prevalence of depression was consistently higher for women than for men. Depression increased from 4.7% in 2015 to 6.3% in 2019 and 6.4% in 2020. In addition, 9.7% in 2015, 10.8% in 2018 and 11, 8% in 2020 of women declared depression.
When stratified by marital status, people who were never married were more likely to be depressed. For people who had never married, there was an increase in cases of depression between 2015 and 2019 in unadjusted models. In both unadjusted and adjusted models, married people, as well as those who were widowed, divorced, or separated, did not experience an increase in depression. Regarding income, those with the lowest family income had the highest frequency of depression, while those with the highest family income had the lowest prevalence of depression.
When education is taken into account, those with a college education had a higher frequency of depression than all other education subgroups. Among individuals who had completed high school, had a college education, or had a graduate degree, the prevalence of depression increased between 2015 and 2019. In both unadjusted and adjusted studies, the frequency of depression among individuals no high school graduation did not change between 2015 and 2019.
Overall, the study results showed a definite increase in both treated and, more importantly, untreated depression. The researchers believe it is essential to expand evidence-based initiatives that support early intervention, prevention and education about depression.