Productivity loss and indirect costs associated with cardiovascular events and related clinical procedures

To our knowledge, this is the first study to examine the cost of workplace absenteeism in high cardiovascular risk patients with a range of CV events and related procedures over multiple years of follow-up. Patients with CVERP experienced significant incremental WA and STD hours and associated costs compared with patients without CVERP. Although the differences were the greatest during the first month following the event, the impact of CVERP was still observed during the first year of follow-up for WA and for up to three years for STD. Productivity losses and indirect costs were highest in patients with CABG and increased with the number of CVERP.

Several studies have evaluated productivity losses resulting from a number of non-CV-related health conditions [39‐41]. Analyses of work loss specifically in patients with CVD have typically focused on specific CV conditions. For example, in an evaluation of indirect costs in patients with ACS, Johnston et al. found that these patients incurred 250 annual mean WA hours (20.8 h per month) and 22 annual mean STD days (14.7 h monthly, assuming 8 h days) [8]. This is consistent with our findings in the first year of follow-up of 23.9 WA PPPM hours for patients with MI and 20.1 WA PPPM hours for patients with unstable angina as their CVERP types, and of 17.1 and 12.7 STD PPPM hours for MI and unstable angina, respectively.

Data on the direct costs associated with CVD are more readily available in the published literature than are those on indirect costs. An analysis of hospitalizations for CV events found higher medical costs for MI and CABG compared with ischemic stroke, HF, angina, and TIA/other cerebrovascular accidents, [42] while an analysis of medical costs in the first month after an MI or CABG found that costs for these events were higher compared with the costs of percutaneous transluminal coronary angioplasty (PTCA), angina, and ischemic stroke [43]. Differences among types of CV events in the average duration of hospitalization have also been documented [e.g., 2.71 days (angina) to 9.23 days (CABG)] [25]. Patients hospitalized for longer periods of time will incur higher medical costs, and by virtue of being hospitalized, will not be working, thus also incurring higher indirect costs. Therefore, it is likely that there is a correlation between direct and indirect costs, at least in the short-term. In our study, in the first month of follow-up, patients with CABG experienced the highest work loss and associated costs, followed by patients with MI and HF.

Medical and productivity costs may vary within a specific CV condition depending on the manner in which the patient is managed. Analyses of patients with ACS found that treatment at the initiating ACS event with non-invasive medical management resulted in the lowest direct and indirect costs, whereas treatment with an invasive CABG procedure produced the highest costs [42]. In our study, patients were hierarchically assigned to a CVERP type, based on the first occurrence of MI, ischemic stroke, unstable angina, revascularization, HF, or TIA. Thus patients assigned as MI may have had an invasive revascularization procedure later in their follow-up, which may partially explain the high WA and STD costs associated with MI. Our data support this hypothesis; more than 60 % of patients with MI at index had a revascularization procedure within three years of their index date.

In the present study, PPPM productivity losses and indirect costs were highest in the first month following CVERP. There are several possible explanations for this finding. First, many of the CVERP types were associated with a hospital admission, and some patients experienced readmissions within 30 days, thereby increasing costs associated with the first month of follow-up. Median 30-day hospital readmission rates have been estimated at 19.9 % and 24.5 % for Medicare patients with acute MI and HF, respectively [13]. Second, the difference between the first month and the one, two, and three years of follow-up may be due in part to the composition of our patient population. Because we were interested in examining indirect costs from the employer perspective, we required patients to be full-time employees and have WA and STD eligibility equivalent to the specific follow-up period. Thus, of the patients included in the first month analyses, only 31 %, 19 %, and 19 % remained for the WA, STD, and combined WA and STD analyses at three years of follow-up. By definition, patients remaining at three years of follow-up represented a working population, and patients unable to continue working and who would likely have accrued higher indirect costs in the longer follow-up periods, were not included in the analyses. Because patients who exited the workforce were not captured in the databases, productivity losses associated with CVERP may have been underestimated. Nevertheless, differences in costs were significantly higher for patients with CVERP compared with those without CVERP in the first month and the first year of follow-up for WA and STD, and additionally in the second and third years of follow-up for STD. These results indicate that this should be an area of concern for employers. In addition, the CVERP and non-CVERP cohorts were well balanced, with the only exception being that a higher proportion of the matched patients without CVERP had cancer than patients with CVERP. Despite their higher prevalence of cancer, patients without CVERP still had lower work loss and indirect costs.

With an estimated $172 billion in CVD-related indirect costs in 2010 in the United States, [2] programs that target prevention of CVD offer the potential for considerable cost savings to employers [14, 44]. A recent review of the benefits of CV risk reduction programs suggest that the return on investment to employers in terms of savings from decreases in absenteeism, workers’ compensation, disability claims, and presenteeism is substantial [30].

In patients who have already experienced or who are at high risk for experiencing a CV event, lifestyle intervention strategies alone may not be sufficient to maximally reduce CV risk [45, 46]. Current treatment guidelines in the United States recommend lipid-lowering therapy in addition to lifestyle modifications to lower LDL-C for high risk primary prevention and secondary prevention patients [47]. Lipid-lowering therapy that decreases LDL-C reduces the occurrence of both fatal and non-fatal CV events in high risk individuals [32, 48]. This study demonstrated the high productivity losses and indirect costs associated with the occurrence of CVERP, especially for CABG and MI (Fig. 3). Pharmacological treatments aimed at lowering LDL-C, via their ability to reduce the occurrence of fatal and non-fatal CV events and related procedures, such as CABG and MI, could help to reduce these substantial productivity losses and associated costs.

Several limitations of the present study should be noted. First, administrative claims were used to select patients with hyperlipidemia and CVERP and any miscoding may have resulted in the misclassification of patients, a limitation that is generalizable to all claims data analyses. Second, because the Truven Health Research Databases contain employees with commercial health insurance provided by large employers, findings from the study may not be generalizable to the entire working population in the United States, especially to employees of smaller employers. In addition, the gender distribution of the study population was skewed toward male, as CVERP are more prevalent in males. The HPM database has a balanced gender distribution and previous productivity studies (e.g., asthma, rheumatoid arthritis) using the HPM database have not shown similarly skewed gender distributions. [31, 49, 50]. Third, the HPM database does not include data on presenteeism, or on-the-job productivity loss [51]. This may have resulted in underestimation of true indirect costs. Fourth, observational analyses such as the present study may be subject to residual confounding despite the use of propensity score matching, especially for characteristics that are not observed in claims data. The observed demographic and clinical characteristics were well balanced in this study, suggesting a successfully matched comparison cohort of patients with and without CVERP. However, we were not able to match the samples based on characteristics of employers, such as features of employers’ leave policies, which may have resulted in residual differences between the cohorts. During propensity score matching, the most severe patients with CVERP (<3 %) were dropped from the analyses due to the inability to find adequately matched patients without CVERP; this may also have resulted in underestimation of indirect costs. Multivariate regression analyses were also conducted to control for patients’ demographic and clinical characteristics and the estimated incremental hours associated with CVERP were consistent with the results based on propensity score matching. Fifth, because absenteeism in the database used for this study includes vacation, holidays, and jury duty in addition to sick leave, the absolute hours of WA reported are likely greater than actual leave due to illness. However, this limitation applies to both the CVERP and non-CVERP cohorts; therefore the impact should be minimal when comparing results between cohorts. As discussed above, because the study sample was drawn from large employers, the results may not reflect the productivity losses of small employers; the BLS average wage rates used in our study reflect both small and large employers, and small employers typically have a lower average wage rate [52]. Indirect costs for this study may consequently have been underestimated. Finally, this study examined productivity loss from the employers’ perspective. Future analysis that investigates the indirect cost savings from the patients’ perspective would help provide a more complete picture of indirect costs associated with CVERP.