Heart disease may precipitate depression in certain people with lupus
What is the topic?
Depression occurs commonly in people with lupus, as does heart disease. However, it is unknown whether one may trigger or contribute to the development of the other. Increased understanding of factors that may contribute to depression in people with lupus can aid future strategies to prevent and treat depression in this population.
This is the first study to evaluate the development of depression in a large group of lupus patients over time.
What did the researchers hope to learn?
The researchers hoped to learn about lupus-related factors, especially heart disease, that may contribute to the development of depression in people with lupus.
Who was studied?
The study included data from 663 adults who participated in the 2004-2008 Lupus Outcomes Study.
How was the study conducted?
The participants were interviewed annually for up to five years. Each interview took 50 minutes and was conducted by telephone. Interviews included questions about disease activity, mental health, history of heart disease, disability, employment, service utilization, and sociodemographic characteristics. For inclusion in the study, each participant must have participated in two consecutive annual interviews.
To determine mental health status, the researchers used the Center for Epidemiological Studies Depression Scale. The Systemic Lupus Activity Questionnaire, a validated, self-report measure, was used to determine lupus disease activity.
The researchers used advanced statistical methods to determine whether specific lupus-related factors could predict the development of another.
What did the researchers find?
The researchers found that 12% of the participants developed depression during the five-year study. The results showed that 70% never developed depression, 17% had one instance of depression, and 18% had more than one instance of depression.
The researchers used multiple kinds of advanced statistical methods to help determine predictors of depression in people with lupus. The following were found to be predictors of depression in people with lupus regardless of the statistical methods used: being aged 40-59, having less than a full college education, being Hispanic/Latino, and having some form of depression upon entry to the study.
When heart- and lupus-related factors were also considered, the presence of type 1 diabetes and lupus disease activity level upon entry to the study were also identified as predictors of depression. In fact, lupus disease activity was found to be the most predictive factor in determining which people with lupus might develop depression.
What were the limitations of the study?
This study has several limitations. First, the Center for Epidemiological Studies Depression Scale used here could identify a minimum level of depression, but could not differentiate among a number of possible depressive disorders. Second, the annual interviews conducted in this study could possibly have missed episodes of depression occurring between interview sessions. Third, it is possible that some of the patients were not fully aware of their true health status and thus could have incorrectly reported this in their interviews. Lastly, this study was not designed to identify predictors of depression related to social life or functionality in daily living (such as increased disability or decreased activity level).
What do the results means for you?
The current finding that depression scores parallel lupus disease activity over time is supported by previous studies. Also supported by previous research on the general population, the current finding that lower educational attainment is associated with the development of depression is not surprising. Increased education seems to have a protective effect against developing depression. People with lupus who also have type I diabetes may be at increased risk of developing depression due to their need to manage two chronic diseases.
Identifying lupus patients at risk for developing depression could greatly increase their quality of life since there are many effective treatment options for depression. This is especially important in the Hispanic/Latino population, for which depression can be more severe, and can go undetected or untreated.
Cardiovascular and disease-related predictors of depression in systemic lupus erythematosus.
Julian LJ, Tonner C, Yelin E, Yazdany J, Trupin L, Criswell LA, and Katz PP. (2011).
Arthritis Care & Research (Hoboken) 63:542-549.