The economic burden experienced by caregivers of LC and CRC patients was significant, ranging from $7,028 for caregivers surveyed when their care recipient was in the initial phase of disease, to $14,234 for caregivers surveyed when the patient was in the terminal phase of disease, and to $19,701 for caregivers surveyed when their care recipient was in the continuing phase of disease. Comparing economic burden for initial and terminal phase patients can be done with a similar time frame in mind (about 7 months), but continuing phase patients had over twice as much time to accrue economic burden (average, 16.7 months). The overall average economic burden for caregivers was around $14,000 (economic burden accrued for 1 year since the patient's diagnosis, on average).
The majority of the total economic burden experienced by informal caregivers of cancer patients—91%—arose from the direct effort of providing informal care to the patient. Nontime costs, comprised of out-of-pocket costs for cancer care, purchases of help in the home, and relocation costs, accounted for the remaining 9%. Given that these latter categories represent direct outlays reported by caregivers ($1,000–$1,800 depending on phase of disease), this category of costs should be of particular concern.
We tested five hypotheses in the multivariable models. Economic burden was greater for caregivers of LC patients than for caregivers of CRC patients, for caregivers evaluated during the patient's continuing phase of disease than for those evaluated during the patient's initial phase of disease, for caregivers of patients diagnosed at stage 4 than for caregivers of those diagnosed at stage 1, and for spousal caregivers than for other relatives and friends. Economic burden did not differ by patient age. Although not a hypothesis, the finding that workers experienced two to three times the economic burden of nonworkers reflects the importance of exploring workplace policy solutions to assist employed informal caregivers.
The total average economic burden for cancer caregivers, $14,000 after 1 year of caregiving, on average, is within the range of other studies. Hayman and colleagues used national data to examine the incremental cost of having cancer treatment in the last year on the intensity and cost of informal care [9
]. They found that cancer treatment was associated with an incremental increase of 3.1 hours per week of informal care, which translated into an additional average yearly cost of $1,200 per patient. This finding is difficult to compare with our findings, because they measured the marginal effect of cancer caregiving in situations in which informal caregiving for other reasons was already taking place. We only measured cancer caregiving effort.
Other studies specifically examining the costs of adult cancer care found that total informal costs were $4,563–$7,290, on average, for a 3-month period, with the higher end of the range for caregivers of patients in the last 6 months of life [19
]. Our estimate of costs during the last 6 months of life—$14,234 for terminal phase patients—is at the upper range of these estimates. Regarding out-of-pocket costs, our totals (around $100–$150 per month, on average, depending on the group) are much less than the $500 a month estimated in another study of cancer caregivers in Canada [21
There are five limitations to keep in mind when interpreting the results from this cross-sectional study. First, valuing caregiving effort for nonworkers at the minimum wage rate may not be accurate because skilled cancer-related care would correspond to a higher wage rate in the labor market [20
]. Thus, this approach may have led to an underestimate of time costs for a substantial proportion of the sample (50% were nonworkers). Second, in our study, economic burden was measured for a single informal caregiver per cancer patient, so the total economic burden faced by the full network of informal caregivers per care recipient could actually be much higher [20
]. Third, our study does not account for the potential health care costs to caregivers of their own health declines resulting from caregiving, despite evidence that informal care can be harmful to the physical and mental health of spousal [22
] and adult children [25
] caregivers. Fourth, the results of this study may not correspond to a nationally representative sample of cancer caregivers. The characteristics of the nonresponding caregivers are unknown, but there is considerable evidence from other studies to suggest that nonrespondents are more likely to be low income, non-white, and sicker than respondents [26
]. If this is true, our results may underestimate the experiences of the caregivers of the sickest cancer patients, as well as the proportion of caregivers who are poor and themselves struggling with ill health [11
]. These first four limitations suggest that economic burden may have been underestimated in our study.
Fifth, however, is a concern that recall bias on the typical weekly hours of informal care provided may have led to an inaccurate estimate of the time costs of caregiving. If hours of care are reported from recent weeks instead of an average across all weeks of care, and recent weeks are higher than the average, the total accumulated time costs will be overestimated. Or, it could be that the longer-term caregivers (continuing care or terminal care) do not remember as well what their care intensity was in the initial weeks, so that their average estimates are biased versus initial caregivers. Therefore, in an effort to provide a lower bound of economic burden, we performed a sensitivity analysis to show what the total economic burden would be if care had occurred over fewer total weeks: in this case, the total economic burden would have been $8,000–$11,000, rather than around $14,000. Without follow-up data, we have no way to discern whether the typical hours provided were misreported or whether this resulted in an over- or underestimate of the time spent caregiving since diagnosis. We also cannot be sure how the countervailing effects mentioned in the previous paragraph would offset any overestimate of caregiving hours.
Our study findings indicate that informal caregivers of LC and CRC patients face significant time costs and work lost. The average total economic burden for informal caregivers, $14,000 accumulated over 1 year, on average, is equivalent to 4 or 5 months of an average worker's annual gross salary [28
]. Considering the time commitment reported across the different groups, it is important to consider that, although the accumulated costs are higher for the group of continuing care caregivers, who had been providing care the longest, the immediate and short-term economic costs of caregiving are likely highest among terminal cancer caregivers, who averaged 25 hours per week of caregiving, versus 15 hours per week for initial and continuing care caregivers (). Thus, the economic burden experienced by cancer caregivers should be included in estimates of the cost of cancer care and cost-effectiveness analyses (CEAs) on cancer care across the full spectrum of a cancer caregiving episode, and especially in the terminal phase of caregiving. In any CEA, the researcher needs to decide a priori how to value a caregiver's time: at the opportunity cost of her time, like we did in this study, because it more accurately reflects the full economic cost of caregiving to the caregiver, or at a lower rate, such as the replacement cost of her time (e.g., at a typical home health aide wage rate), which may be more useful when considering policy options that would reimburse informal caregivers at going market rates. CEA researchers could also perform sensitivity analyses on the ideal quantity of informal care received, if there is evidence that the amount of care provided is below the amount indicated clinically because of time or economic constraints faced by the informal caregiver.
In addition, focusing future research and/or interventions on informal caregivers of cancer patients with a higher economic burden, as identified in the present study, spousal caregivers and employed caregivers in particular, may help to guide our efforts to reduce the associated negative health and economic outcomes among at-risk informal caregivers.