Increased lupus-related risk of work loss
What is the topic?
Some estimates indicate that about half of people with lupus stop working within 10 years of a lupus diagnosis. Several factors were identified in previous studies to be associated with work loss among people with lupus, including lower levels of education, minority race/ethnicity, advanced age, longer disease duration, higher disease activity, and cognitive involvement.
Few studies, however, have been able to relate specific manifestations of lupus (such as brain or skin involvement) to work loss. Further study in this area could help identify risk factors for work loss among people with lupus and could help guide disease-related factors that physicians should follow in their patients over time.
What did the researchers hope to learn?
The researchers hoped to learn about the relationship between the timing of specific lupus manifestations and subsequent work loss.
Who was studied?
The participants were 483 people with lupus who enrolled in the University of California at San Francisco Lupus Outcomes Study (LOS) between 2002 and 2009.
How was the study conducted?
For inclusion in the study, participants must have had a diagnosis of lupus confirmed by review of medical records by a rheumatologist or a nurse working under a rheumatologist’s supervision. Exclusion criteria were as follows: people not employed when initially enrolled in the LOS, those aged 65 years or older, and those with only one LOS interview on file.
Participants were interviewed by phone annually to collect the following information: demographic and socioeconomic characteristics, disease duration (time since diagnosis) and activity, specific lupus manifestations (including thrombotic, or those related to blood clots, neuropsychiatric, and musculoskeletal), general health and functioning, use of medications, health inventory for the previous 12 months, kind and extent of health insurance, and employment status. For all analyses, the length of time until work loss was measured from the point of the first lupus-related incident (such as a blood clot) to the time of the work loss.
What did the researchers find?
Most of the patients included in the study were Caucasian women (although Hispanics, African-Americans, and Asians were also included), aged 35-55 years, who had lupus for an average of about 11 years. Most either graduated from college or attended some college and reported being in excellent or good health. Despite this, about 20% earned 125% or less of the U.S. federal poverty level. About a third of the patients had lost a job since the previous interview and had been at their job for an average of about six years. About 40% of the patients were employed in government, with the rest being equally distributed among professional or technical services, the goods-producing industry, retail, and the service industries.
Thrombotic (blood clot-related), musculoskeletal, and neuropsychiatric events were experienced by 12%, 35%, and 37% of the patients, respectively. About 34% of patients had one lupus manifestation while 24% had two or three. About half of the patients experienced a clinically significant increase in lupus disease activity since the previous interview. Among patients who experienced either a blood clot-related event or increased lupus disease activity, there was a significant decrease in employment within 12 months. These two groups continued to show a decline in employment for at least four years, ending with an employment rate of about 40%. Patients experiencing musculoskeletal or neuropsychiatric events had a less severe loss of employment (although their employment dropped to about 50% by the end of the study). When considering all of the patients together (regardless of the types of lupus manifestations they experienced), about 66% remained employed throughout the 7-year study period.
Additional analyses revealed that sociodemographics, employment characteristics, and lupus characteristics all contributed to the risk of work loss. In general, the risk of work loss among people with lupus increased with advancing age, greater disease activity, and an increased number of the different types of disease manifestations, especially if blood-clot related events was among them. In some analyses, lupus patients who had a longer job tenure were at decreased risk of work loss.
What were the limitations of the study?
During their annual phone interviews, lupus patients may not have reported information about blood-clot related events in an entirely accurate manner, perhaps due to its complex medical nature. Also, since the researchers categorized blood-clot related events and neuropsychiatric events uniquely (even though blood clots occurring in the brain may correctly be categorized as an incidence of neuropsychiatric lupus), the researchers may have underestimated the true incidence of neuropsychiatric lupus among the study participants. Lastly, too few of the lupus patients experienced kidney involvement to include that as one of the lupus manifestations studied.
What do the results mean for you?
Blood clot-related events were most significantly associated with risk of work loss in this study. However, patients experiencing musculoskeletal or neuropsychiatric events were also at increased risk of work loss, but it was less severe and more delayed in time (from the time of initial lupus diagnosis). In addition, regardless of the types of lupus manifestations experienced, lupus patients experiencing increased disease activity were also at higher risk of work loss.
Some blood clot-related events may be preventable (such as by not smoking, as well as by treating high blood pressure and/or high cholesterol). The results highlight the importance of monitoring blood clot-related events in people with lupus, as this may have a significant impact on their work life in the future. Interventions geared towards decreasing risk factors associated with work loss among people with lupus may help to improve employment outcomes.
Longitudinal study of the impact of incident organ manifestations and increased disease activity on work loss among persons with systemic lupus erythematosus
Yelin E, Tonner C, Trupin L, Gansky SA, Julian L, Katz P, Yazdany J, Kaiser R, and Criswell LA. (2012).
Arthritis Care & Research (Hoboken) 64:169-75.