Lerner, Debra MS, PhD; Mirza, Fadi MD; Chang, Hong PhD; Renzulli, Karen PsyD; Perch, Katherine BA; Chelmow, David MD
* Describe the characteristics and health outcomes of women with symptomatic, untreated uterine fibroids.
* Understand the impact of this condition on functioning and productivity at work, and the importance of considering functional improvement when assessing treatment outcomes.
* Discuss how the work impact of symptomatic uterine fibroids is related to factors like the patient’s mental health, race/ethnicity, and symptom burden.
With 59% of women in the United States currently employed,1 reducing the burden of health problems on women’s ability to work and work productivity is an important patient care, business, and public policy issue. The aim of this study is to assess the impact on employed women of uterine fibroids (UFs), a common condition occurring mainly in the fourth and fifth decades of life.2
An estimated 30% of reproductive-age women in the United States have fibroids.3 Although many women with fibroids experience no symptoms, others report having pelvic pain and pressure, heavy menstrual periods or other abnormal uterine bleeding, pain during sexual intercourse, and/or urinary problems.4 Studies have found that fibroids frequently take a large toll on women’s health-related quality of life (HRQOL).5–7
Fortunately, for women requiring treatment, the number of options has been expanding. Procedures such as hysteroscopic myomectomy and uterine artery embolization are replacing more invasive techniques such as hysterectomy and abdominal myomectomy. However, in this rapidly changing treatment environment, the relative effectiveness of the different treatment options has not been fully established.2
Despite this condition’s substantial personal impact and treatment cost,2 research regarding the impact of UFs on women’s work performance and productivity is scarce.5 Hartmann et al8 conducted an analysis of employer databases and found that, within 1 year of diagnosis, women with UFs were three times more likely than controls to have filed disability claims; the rates were 16% for UF patients versus 5% for controls, for a relative risk of 3.1. Using data from a multicenter clinical trial in Ontario, Pron et al4 reported that among the 85% of women with UFs who were employed, 40% had recent work absences due to the condition.
In this study, we address the impact of UFs on two dimensions of work productivity: at-work performance limitations and productivity loss (known as presenteeism), and missed work time (absenteeism). We hypothesized that symptomatic fibroids interfere with at-work performance and reduce productivity. In addition to testing this hypothesis, we assessed variables associated with the outcomes.
Materials and Methods
This cohort study included women defined as having symptomatic fibroids (cases) and a group of women defined as generally healthy (controls). Study participants were current or former patients of the Tufts Medical Center in Boston, MA, and the Fallon Clinic in Worcester, MA.
For both groups, the inclusion criteria were 18 to 53 years of age and currently employed at least 15 hours per week. Exclusions for both groups included history of drug or alcohol abuse; other physical and/or mental chronic conditions that may significantly limit work or other activities; pending or active workers’ compensation or disability claim; non-English speaking; participating in a treatment trial; peri- or postmenopausal; less than 3 months postpartum and postlactation; prior myomectomy within 1 year of study or pending myomectomy; uterine artery embolization or endometrial ablation within prior 6 months of study or pending; and/or hysterectomy or bilateral oopherectomy. The treatment exclusions ensured that we were measuring the burden of UFs on the cases and not the treatment.
Eligibility in the UF group was based on having at least one fibroid with a diameter ≥2 cm, or multiple small fibroids with a uterine volume of ≥200 cm on ultrasound. Intracavity, intramural, submucosal, and subserosal fibroids qualified. Additionally, UF group eligibility required patients to have one or more of the following symptoms according to the medical chart and eligibility screening interview:
* self-reported heavy bleeding, bleeding for long periods of time, blood clots passing during menstrual periods;
* pelvic discomfort (not due to problems other than fibroids) including chronic pelvic pressure, tightness, and/or pain;
* bladder dysfunction, usually pressure symptoms, not due to known urinary tract disorder;
* rectal pain or pressure and bowel dysfunction not related to known bowel disorder; and/or
Patients were asked specifically about how bothered they were by each of these symptoms in the past 4 weeks. To be eligible for the UF group, patients had to report being “bothered a little” by two or more symptoms or being “bothered somewhat” or “bothered a great deal” by one symptom or more. It was important to identify women who are relatively bothered by symptoms because this is the group that is considered important from a clinical perspective. Fibroids are a benign disease, whose health consequences and need for clinical assessment, monitoring and/or treatment are generally determined by the symptoms they cause and resultant impact on the patient’s activities/HRQOL.
In addition to the general criteria listed previously, eligibility for the control group required the absence of fibroids and the presence of regular menstrual periods, based on medical chart data and self-report. Women with a last menstrual period 6 weeks ago or longer or self-reported irregular periods were excluded. In addition, of 11 fibroid-related symptoms listed, controls also had to report being “bothered a little” by no more than two symptoms or “not bothered at all” by any symptom.
To ensure that eligibility was thoroughly evaluated, we used a multitiered procedure consisting of searching the clinics’ databases, performing medical chart review, obtaining physician confirmation of eligibility, and conducting patient telephone screening. Most of the screened and enrolled patients were identified initially by searching the databases for age-eligible women who were seen by physicians between 2003 and 2006 and had the relevant diagnostic codes. For the UF group, we searched for diagnostic codes for fibroids (International Classification of Diseases, 9th revision codes 218.0, 218.1, or 218.2) and/or potentially fibroid-related symptoms (625.9, 626.9, 626.8, 626.6, 625.3, 789.3, 789.4, 626.2, or 626.4). For the control group, we searched for patients with one or more visits for a routine gynecological examination (code V72.3) and none of the other fibroid or fibroid-related codes. In addition, potentially eligible UF group patients could be identified on the basis of referrals from physicians within the participating obstetrics and gynecology (OB/GYN) clinics. Potentially eligible control group patients could be identified if they responded to a study ad, which was posted at one site.
Next, the names of potentially eligible UF group patients were given to the study clinicians (physicians and/or nurses), who reviewed their charts. A standard chart review form was developed for this purpose. The chart review was performed at one site by a study coauthor, an OB/GYN chief resident and, at the other site, by a registered nurse. Charts of patients who had an eligible diagnosis and/or procedure code, had visited a primary care, internal medicine, or gynecology clinic within the prior 2 years, and were age-eligible were reviewed.
Following this step, an e-mail was sent to the treating physician indicating the study’s intention to contact his/her patient and requesting confirmation of eligibility. Physicians also could decline permission for patient contact at this point.
A study representative then retrieved contact information for each potentially eligible patient from clinic records, and mailed an introductory letter. This letter described the study’s purpose and procedures (including the opt-out procedure). If contact information was missing from the chart or patient database, the patient was excluded.
Ten days after the mailing, the study’s research assistant attempted to call each patient who had not opted out of participating and conduct a screening interview. The interview included questions covering all of the relevant eligibility criteria. For example, control group candidates were asked detailed questions about their gynecological health history including diagnoses, treatments, symptoms, menstrual periods, and fertility.
Eligible women who were interested in participating were mailed a package containing a questionnaire, an Informed Consent form, a HIPAA Research Authorization form, instructions for completing the forms, and stamped self-addressed envelopes (one for the research forms and one for the completed questionnaire). The study’s procedures were approved by the Tufts University Health Sciences Campus Institutional Review Board.
Patients were instructed to read and sign the consent and HIPAA forms and return them in the designated stamped envelope. All UF and control group enrollees were further instructed to complete the half-hour long questionnaire within 2 days of the end of their next menstrual period. A stamped, self-addressed envelope was provided. To increase adherence to the protocol, periodic phone reminders and postcards were sent. Upon returning the completed questionnaire and study forms, each participant received $50.
The database search of qualifying age and diagnostic codes identified 881 patients for UF group eligibility review and 410 for control group review (Table 1). Of the 881, 652 (74%) were excluded by chart review and 229 (26%) were eligible to continue (Table 2). The leading reasons for UF group exclusion were the absence of a qualifying fibroid (30% of 881), no documented fibroid-related symptoms (26%) and hysterectomy (15%).
Of the 229 women eligible for the UF group after chart review, 161 (70%) were screened out and 68 (30%) were eligible to enroll. Reasons for screening out included patient or physician opt-out before phone screening (9%); unable to reach (26%) due to either no answer or inaccurate or incomplete contact information); ineligibility based on a completed phone screen (22%); or refused participation (9%). After enrollment, the final UF group response rate was 58/68 (85%).
For the control group, chart review excluded 197/410 (48%), leaving 213 (52%) eligible to continue. Of these, 159 were screened out for one of the following reasons: opted out (3%), unable to reach (44%), ineligible phone screen (10%), or refused (17%). The relatively high rate of unreachable patients reflects inaccuracies in the contact information contained in patient records, which in some cases was years old. Another 17 potential controls responded to a posted newsletter advertisement and met screening criteria, resulting in a total of 71 eligible controls. After enrollment, the final control group response was 56/71 (79%).
The main outcome measures were assessed with the 25-item Work Limitations Questionnaire (WLQ) for measuring at-work performance deficits and the four-item WLQ Work Absence Module.9,10 The WLQ has been extensively validated though not used for this patient group previously. The WLQ at-work performance scales reflect the percentage of time in the prior 2 weeks that health problems impaired the person’s ability to perform the following types of job demands: time management, physical job demands, mental and interpersonal job demands, and output demands. WLQ items ask explicitly about the frequency with which physical health or emotional problems caused difficulty performing specific work tasks in the past 2 weeks. In addition to the four scales, the WLQ scale scores are weighted and aggregated to produce the WLQ Productivity Loss score.11 This score reflects the percentage difference in productivity from a benchmark group of healthy (not limited) workers.
The WLQ Absence Module elicits reports of the number of work hours missed due to health problems in the past 2 weeks. The percentage of productivity lost due to absenteeism is the number of hours missed in the past 2 weeks divided by the person’s usual weekly work hours.
Both productivity loss indicators were converted to productivity costs (in dollars) by multiplying the productivity loss percentage by the person’s self-reported annual salary. Using the salary to determine the cost is relatively conservative because it does not include costs associated with finding substitute workers or other potential consequences such as additional losses in team-based work settings.
The main independent variable in the study’s analyses was a patient group indicator (1 = UF group and 0 = controls). Several additional variables were measured. For both groups, the survey assessed history of comorbid conditions (using a modified version of the National Health Interview survey inventory),12 self-rating of general health based on the SF-36 excellent to poor scale,13 depression severity based on the Patient Health Questionnaire (PHQ-9),14,15 pain based on the Treatment Outcomes in Pain Survey (TOPS),16 and recent hospitalizations and physician visits.
Within the UF group, measures included fibroid history (eg, date first diagnosed) and fibroid treatment (surgical and/or medical). We obtained self-reported gynecological symptoms and symptom severity and pregnancy history, and administered the UFS-QOL, an instrument assessing HRQOL. The UFS-QOL mainly asks about the person’s experience of symptoms (eg, heavy bleeding).17
For both groups, sociodemographic survey questions addressed years of education, age, race/ethnicity (coded as White = 1; Non-White = 0), annual income, number of usual work hours, marital status, and number of children. To assess job requirements, we measured physical and psychological job demands based on the Job Content Questionnaire scales, job control, an indicator of autonomy at work, and job satisfaction.18
Additionally, for the UF group only, chart review at baseline provided data on number of fibroids, UF size and location. Fibroids were coded by the OB/GYN specialists on this study as small, medium or large based on estimation of size at the most recent pelvic examination or actual uterine volumes calculated from available ultrasounds.
The analytic objectives were as follows:
1. describe the main outcomes and other key variables;
2. compare UF versus control group differences in outcomes; and
3. within the UF group, assess the importance to outcomes of fibroid-related symptom severity and other variables.
We report descriptive summary statistics for all of the variables using, as appropriate, means (and their standard deviations), and/or percentages. We assessed univariate case-control differences on the study variables using t-tests or χ2. We report the adjusted differences of WLQ scores and productivity loss (%). The adjusted scores were generated from a set of linear regression equations that included the indicator variable for UF versus control, variables adjusting for sociodemographic and employment characteristics. These included age in years, an indicator for race/ethnicity (White vs non-White), annual income in dollars, and number of weekly working hours.
For the fibroid group only, we used multiple regression analysis to test the associations between specific outcome variables (eg, at-work limitations, absenteeism, and related productivity losses), and the following: sociodemographics (age, education, race, and income); fibroid characteristics (UFS-QOL score, fibroid size defined as large vs small and medium vs small); TOPS pain score; PHQ-9 depression severity score; work characteristics (psychological job demands and control); and a study site indicator. Results are reported as β coefficients and their standard errors and P values. STATA version 9.019 was used for all statistical analyses.
Within the UF group, the mean (SD) age was 45.1 years (6.6) and 70.6% were White (Table 3). The control group was significantly younger (mean age, 40.6 years [8.8]; P = 0.002) and a higher proportion of its participants were White (94.6%; P < 0.001). The percentage married was 56.9 versus 64.3 (P = 0.424), and the mean number of children in the household was 0.7 (0.9) versus 1.2 (1.2); (P = 0.020). There was no difference in mean years of education (P = 0.255). Median income was significantly higher in the control group ($54,000 vs $40,320; P = 0.003).
The mean number of hours worked per week was similar for the groups (P = 0.408; Table 3). With regard to job conditions, the UF group had a mean score of 57.1 (18.4) on the psychological job demands scale, and 61.4 (16.8) on the job control scale, both of which were not significantly different than control group scores (P = 0.393 and 0.330, respectively). There were no group differences in job satisfaction with means of 2.5 in either group, indicating moderate satisfaction (P = 0.853). The groups were different with regard to the size of the firms in which they were employed (P ≤ 0.001).
The UF group had a mean of 1.0 (1.1) chronic comorbid condition (compared with 0.8 [0.9] for controls; P = 0.262), and a mean of 2.4 (1.9) pregnancies, which was similar for the control group (P = 0.731; Table 3). The percentage of subjects reporting difficulty with pregnancy was 8.7% in the UF group and 8.9% in the control group (P = 0.977). Compared with controls, self-rated health perception was worse in the UF group (72.7 [21.5] vs 80.5 [16.5]; P = 0.037).
In contrast to these results, the UF group reported significantly more severe depression symptoms (5.9 [4.2] vs 3.2 [3.5]; P = 0.002), and the mean score was consistent with mild depression severity. Pain was also significantly worse in the UF group (33.4 [22.0] vs 16.8 [19.7]; P = 0.001). Mean scores classify the level of pain as moderate.
In the prior year, the UF group had been hospitalized overnight once on average (as in the control group; P = 0.355). Both groups had a similar number of doctor’s office visits (1.8 [4.9] vs 2.1 [4.3]; P = 0.773).
With regard to symptoms (Table 3), more than half in the UF group (57.9%) reported heavy bleeding compared with 10.5% of controls (P < 0.001), 30.8% experienced pelvic pressure and/or pain versus 5.8% (P < 0.001), 31.5% reported frequent urination versus 4.2% (P < 0.001), and 55.5% suffered from fatigue versus 23.6% (P < 0.001). The UFS-QOL score was mean 64.2 (23.4). According to the classification of fibroid size, 23.5% were large, 41.2% were medium-sized, and 35.3% were small.
Adjusting for differences in age, race/ethnicity, income, and weekly work hours, the UF group had significantly higher mean at-work performance limitations (Fig. 1; Table 3). The UF group, on average, was impaired approximately 2 out of 10 days of the prior 2 weeks, compared with less than 1 day per week for the control group (WLQ scale differences ranging from P < 0.001 to P = 0.039). For instance, according to adjusted mean scores, health problems interfered with time management 21.7% of the time in the prior 2 weeks compared with the control group’s rate of 7.8% (P = 0.005). Ability to manage mental and interpersonal job tasks was impaired 17.2% of the time versus 9.4% (P = 0.032). The average per person mean at-work productivity loss was 4.3% compared with 2.1% (P = 0.005), and the mean (SD) per person productivity cost was $2341 (2855) versus $836 (1048); (P = 0.007). Assuming the same median salary for both groups, the differences would be $2086 versus $1055; (P = 0.020).
According to adjusted analysis, the UF and control groups did not have significantly different absence rates (0.42 days vs 0.15 days; P = 0.134). In the UF group, the average per person productivity loss due to absenteeism was 5.4% versus 1.4% for controls (P = 0.005), resulting in a productivity cost of $2045 (4010) versus $540 (1698); (P = 0.021).
In models addressing at-work performance deficits (Table 4), the most important outcome predictors were depression severity, race/ethnicity, and fibroid-specific HRQOL. The more symptomatic the women were, the greater the at-work performance deficits (P ≤ 0.020 in each model) and at-work productivity loss (P ≤ 0.001). Racial/ethnic minority status was associated with more difficulty managing physical and mental-interpersonal job tasks (P = 0.011 and P = 0.016, respectively) and more at-work productivity loss (P = 0.029). Similarly, lower scores on the UFS-QOL scale were associated with more difficulty managing physical and mental-interpersonal job tasks (P = 0.013 and P = 0.007, respectively) and more at-work productivity loss (P = 0.027). The five at-work performance models explained between 0.61 and 0.75 of the variance in those outcomes. The absence models did not identify important correlates of outcome.
Physicians are increasingly challenged to diagnose and treat patients with complex chronic conditions that are functionally limiting and have substantial social and economic consequences. The care of patients with UFs encompasses these challenges. This is the first study to address the degree to which women with fibroids and fibroid-related symptoms, before major intervention, are impacted at work. This study found that fibroids are related to losses in ability to function at work and productivity loss. This is new and important for two reasons. First, the results underscore the necessity of considering the functional improvement of women with symptomatic fibroids to be an important treatment outcome. Next, they suggest that one of the standards by which fibroid treatments should be evaluated is the degree to which they impact work productivity and productivity costs.
To separate the work impact of symptoms versus treatment (eg, time off to recover from a procedure), we specifically attempted to identify women who were bothered by fibroid-related symptoms but were not taking medication, and had not been recently treated or had treatment planned. After screening, we discovered this group constituted a small subgroup of all UF patients being followed in clinics, as most patients sought treatment, or had asymptomatic fibroids. The detailed eligibility determination process added to the study’s internal validity. However, its restrictive entry criteria and subsequent small sample size may have limited the study’s external validity. Thus, the study includes the subgroup of women with fibroids who have either chosen to live with their symptoms, or have symptoms but have not yet reached the point where they have opted for treatment. With several treatment options available, the group not receiving treatment may be relatively small.
Several other methodological features of the study are important to mention. 1) Although we used a variety of procedures to ensure that the UF group had only that condition and that symptoms were attributed to fibroids, it is possible that some symptoms were not caused by fibroids. However, in general, these patients were receiving care in specialty clinics, had standard clinical evaluations for other causes, and clinically were thought to have the symptoms from the fibroids. 2) We obtained only retrospective chart data. As a result, some information, such as contact information, was missing or outdated. If subjects with missing contact information were different from those within the system, bias could have been introduced. 3) The two groups exhibited some baseline differences, which we adjusted for statistically. However, adjustments may not be adequate to control for differences, both measured and unmeasured. 4) Variables such as chronic health problems, work conditions, and utilization were entirely self-reported. We did not test their reliability and validity specifically within this population, but self-reports of these and other study variables have generally performed well psychometrically.9,10,20 5) The locations chosen for participation may limit our ability to generalize results. We extensively and systematically reviewed patient databases and charts from two sites, an academic medical center and a network of health clinics, ensuring that the sampling was thorough. While academic medical centers tend to treat relatively sick patients, our criteria would have excluded most of the tertiary care population, leaving a sample similar to one seen in primary care. These sites are similar to those where many patients receive care.
Study strengths included the careful review and sampling procedures, use of well-established validated outcome measures, and others such as depression, health perception, pain, HRQOL, and work demands. The breadth of the measurement also enabled us to model the effects of sociodemographic, clinical, and health variables.
Study results suggest that absences are no greater for women with fibroids than for healthy women. However, in contrast to this finding, results suggest that symptomatic fibroids interfere substantially with ability to function at work. Additionally, productivity loss related to fibroids was just under 5% on average and almost 2.5% greater than the amount observed in the control group. The burden of UFs can be put into perspective by referencing results from prior research on the adverse effects of other chronic health problems. The UF group had mean at-work productivity deficits that, while lower than observed for primary care patient samples with major depressive disorder or osteoarthritis,21,22 are similar to those documented for clinic patients with diagnosed migraine headache.23
The impact on work varied in relation to the mental health of the patient, race/ethnicity, and the burden of symptoms as measured by the UFS-QOL. This analysis was constrained by the study’s cross-sectional design. As a result, we do not know whether the direction of the relationship between work difficulties reported on the WLQ and symptom burden reported on the UFS-QOL. However, the results regarding depression are thought-provoking. For instance, the relationship of depression to outcomes may reflect selection bias (more women with depression seeking treatment), or a secondary consequence of fibroids. However, depression symptoms such as fatigue and difficulty concentrating (a common pain response) could overlap with fibroid symptoms. The cooccurrence of depression and UF symptoms suggests the critical importance of carefully screening for depression and, if depression is confirmed, managing both conditions and their functional impact. As with other populations, there is a high likelihood that depression is being under-detected and under-treated.24 Moreover, the absence of significant differences in physician office visits may suggest that fibroid symptom care is being underutilized. This may be the result of excluding women in treatment or a propensity of working women with fibroids to avoid treatment.
The finding of a racial/ethnic disparity in work outcomes among non-Whites is not unexpected given that previous research has identified a higher UF prevalence among women of color.25 In this sample, Whites and Non-Whites were not significantly different with regard to mean age, years of education, income, general health perception, psychological job demands, job control, pain, or depression. Additionally, there were no significant differences in fibroid size, and HRQOL scores. With only 17 patients in the Non-White group, there is little we can conclude. Studies of the sources of disparities in condition prevalence and outcomes are essential.
The lack of significant group differences in work absences and lack of meaningful associations in the absence models may result from the questions’ 2-week reference period, which may have been too brief to capture meaningful differences. Alternatively, the results may reflect broader patterns of sick day usage. Our prior focus group research involving employees with chronic health problems (unpublished) has indicated that they may not take time off from work in order to avoid negative repercussions, to bank time for when they are completely unable to work, or because they do not have any paid sick days available. A trend among employers toward giving employees a set number of paid time-off days to be used for any reason may also be encouraging workers to save unused days for vacation. Our study did not ask more in-depth questions about absences nor did we include variables such as company benefits policies, which may have been important.
Results suggest the value of assessing and managing patients’ functional deficits affecting employment and other social roles. Detecting and treating symptoms in women with fibroids, and attending to the possibility of depression, may help prevent adverse work outcomes.
We acknowledge the generous sponsorship of TAP Pharmaceutical Products Inc. to support this project.
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