Willingness-to-pay and Time Trade-off: The Burden of Disease in Patients with Benign Hyperpigmentation

| May 1, 2019

 J Clin Aesthet Dermatol. 2019;12(5):46–48

by Mayra B. C. Maymone, MD, DSc; Susruthi Rajanala, BA; Rafael Widjajahakim, MS; Eric Secemsky, MD, MSc; Dana Saade, MD; and Neelam A. Vashi, MD

Drs. Maymone, Saade, and Vashi, Ms. Rajanala, and Mr. Widjajahakim are with the Department of Dermatology at the Boston University School of Medicine in Boston, Massachusetts. Dr. Secemsky is with the Department of Medicine at Beth Israel Deaconess Medical Center and Harvard Medical School in Boston, Massachusetts. Dr. Vashi is also with the United States Department of Veteran Affairs in Boston, Massachusetts.

FUNDING: The study was funded by a Boston University Department of Dermatology internal grant. 

DISCLOSURES: The authors have no conflicts of interest relevant to the content of this article.

ABSTRACT: Objective. We assessed willingness-to-pay (WTP) and time trade-off (TTO) as methods to quantify the disease burden of benign hyperpigmentation.

Design. This was a cross-sectional pilot study that included 85 adults. A paper survey was used to collect demographic and health utility information; an accompanying dermatological exam assessed disease severity.

Setting.This was a single-site study performed at an urban dermatology clinic.

Participants.Adults 18 years of age or older who spoke English, Spanish, or Portuguese were included.

Measurements. Utility measures included WTP, TTO, and time spent concealing the condition; correlation with quality of life was also assessed.

Results.Mean WTP for 25-percent improvement (WTP25) of the skin condition was $38.95; for a 50-percent improvement (WTP50), $83.18. Participants were willing to give up 1.4 hours per day to receive a therapy that would completely cure their condition. The average proportion of monthly income that participants were willing to spend on a therapy that could cure their condition was 13.3 percent. Daily concealment time was, on average, 20.8 minutes, which correlated with a worsened quality of life.

Conclusion. Disease burden was high, overall, for benign hyperpigmentation conditions. Health utilities offer a patient-centered method of assessing impact on quality of life.

KEYWORDS: Willingness-to-pay, time trade-off, skin hyperpigmentation, quality of life, benign hyperpigmentation


Hyperpigmentation disorders comprise a large group of benign skin conditions, the prevalence of which varies depending on race and ethnicity. Despite often being considered a cosmetic condition, hyperpigmentation disorders have been shown to negatively impact quality of life and psychosocial well-being of patients, especially when facial skin is involved.1,2 Utility measures of healthcare are based on patient preferences and can assess how desirable certain health outcomes are for patients, as well as time trade-offs that patients are willing to make in order to achieve an outcome. Such utility measures can be used to quantify disease burden and impact on quality of life, as well as analyze the cost-effectiveness of an intervention.3

Time trade-off (TTO) considers how many hours patients would give up per day in order to be completely free of disease. Willingness-to-pay (WTP) is a monetary measure similar to a utility that assesses individual preferences for a hypothetical treatment by asking how much money patients are willing to spend to potentially be cured of a condition. Since WTP is measured in monetary units, one might consider it as assigning a dollar value to a particular health state. In order to standardize the results, income level is also considered.4 The use of such measures might be helpful in understanding patient preoccupation with cosmetically unappealing dermatological conditions, and because valuations of time and money can vary between patients, WTP and TTO both measure distinct preferences. WTP might be particularly useful, considering that the treatments for benign skin conditions might be affordable enough for patients to consider paying out-of-pocket. In addition, patients might more easily imagine the monetary value of a treatment rather than a time value.4 

Methods

This single-site, cross-sectional pilot study involved 85 adults who presented to a dermatology clinic with skin hyperpigmentation from February through August 2016. A paper survey questionnaire, offered in English, Spanish, and Portuguese, collected demographic characteristics, including sex, age, race, ethnicity, marital status, and employment status (Figure 1). The questionnaires from two participants were excluded due to missing information. Mean income was determined by each participant’s zip code. Utility measures included the following: WTP for 50 percent and 25-percent reduction of skin disease in dollar units; TTO in hours for complete cure of hyperpigmentation; Dermatology Life Quality Index (DLQI); daily time spent concealing dark spots with makeup; and treatments the patients were willing to try to improve their hyperpigmentation. A single board-certified dermatologist determined Fitzpatrick skin type and disease severity. Disease severity was classified by the Melasma Area Severity Index (MASI) score, Post-acne Hyperpigmentation Index (PAHPI), and body surface area (BSA) for the diagnoses of lentigines, nevi, and other disorders of hyperpigmentation.5,6 Statistical analysis was performed using the Statistical Analysis System (SAS) version 9.4 (SAS Institute, Cary, North Carolina). The study was approved by the Boston University Institutional Review Board, and informed consent was obtained from all participants.

Results

Of the study cohort, the average age was 42.2±12.3, 89 percent of participants were women, 48 percent were college graduates, and 72 percent had an annual income below the median annual state household income (Table 1). Of all participants, 11 percent had Fitzpatrick Skin Types I to II, 55 percent had III to IV, and 34 percent had V to VI. Postinflammatory hyperpigmentation (PIH) and melasma represented 66 percent of our sample. The majority of participants were willing to try creams (88%) and lasers (77%) to improve their hyperpigmentation, while less than half were willing to try oral medications (45%) or novel/experimental therapies (28%). Overall, the mean WTP for 25-percent improvement (WTP25) of their skin condition was $38.95, and for 50-percent improvement, (WTP50), $83.18. Participants reported they were willing to give up 1.4 hours per day to receive a therapy that would completely cure their condition. The average proportion of monthly income that participants reported they were willing to spend on a therapy that could cure their condition was 13.3 percent. Daily time spent on concealment was, on average, 20.8 minutes and was correlative with worsened quality of life as assessed by the DLQI (Spearman’s coefficient=0.30; p<0.01) as well as with WTP25 (Spearman’s coefficient=0.35; p<0.05) and WTP50 (Spearman’s coefficient=0.32; p<0.05).

Discussion

Our data suggest that disease burden was, overall, severe in patients with hyperpigmentation disorders, and utility measures, particularly WTP and TTO, might be useful in determining the daily impact of disease and treatment preferences. We found that the WTP for a curative treatment was greater than that previously observed among patients with rosacea and vitiligo.7 This suggests that hyperpigmentation disorders have a greater negative impact on daily life and that patients expect to pay more out-of-pocket for conditions that are often considered cosmetic. Interestingly, WTP25 more strongly correlated with DLQI (Spearman’s coefficient=0.31; p<0.05) than did WTP50 (Spearman’s coefficient=0.16; p=0.2), suggesting that, even with a worsened quality of life, patients might not be willing to spend a proportionately higher amount for a 50-percent reduction in disease severity compared with a 25-percent reduction. The TTO per day for a hypothetical cure in our study was 1.4 hours; this was lower than that reported for psoriasis (2.8 hours) and melasma (1.9 hours) and neared the WTP reported by patients with port wine stains (1.2 hours).8,9 Interestingly, TTO was greatest among those with postinflammatory hyperpigmentation, suggesting this population might receive the greatest benefit from intervention. 

To date, no study has assessed the time spent on concealment as a patient-centered metric to evaluate disease burden among patients. This measure correlated with quality of life and might be an important gauge of condition severity, though it is limited to some degree because patients have varying preferences regarding makeup usage.

Limitations. The study should be interpreted in the context of its design. This was a single-site study, which restricts the generalizability of our results, and the small sample size limits our findings. 

Conclusion

Our findings suggest that benign hyperpigmentation can have a substantial effect has on quality of life as measured by the amount of time and money patients are willing to spend to alleviate themselves of disease. Although limited by sample size and design, the information collected herein on WTP preferences might assist physicians in gauging the impact of hyperpigmentation disorders on patient quality of life and might be useful in guiding therapeutic decisions. 

References

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  2. Sanchez MR. Cutaneous diseases in latinos. Dermatol Clin. 2003 Oct;21(4):689–697. 
  3. Torrance GW. Utility measurement in healthcare. Pharmacoeconomics. 2006; 24(11):1069–1078.
  4. Seidler AM, Bayoumi AM, Goldstein MK, et al. Willingness to pay in dermatology: assessment of the burden of skin diseases. J Invest Dermatol. 2012;132(7):1785–1790. 
  5. Pandya AG, Hynan LS, Bhore R, et al. Reliability assessment and validation of the Melasma Area and Severity Index (MASI) and a new modified MASI scoring method. J Am Acad Dermatol. 2011;64(1):78–83.e2. 
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  7. Beikert FC, Langenbruch AK, Radtke MA, Augustin M. Willingness to pay and quality of life in patients with rosacea. J Eur Acad Dermatol Venereol. 2013;27(6):734–738. 
  8. Leeyaphan C, Wanitphakdeedecha R, Manuskiatti W, Kulthanan K. Measuring melasma patients’ quality of life using willingness to pay and time trade-off methods in Thai population. BMC Dermatol. 2011;11(1):16.
  9. Schiffner R, Brunnberg S, Hohenleutner U, et al. Willingness to pay and time trade-off: Useful utility indicators for the assessment of quality of life and patient satisfaction in patients with port wine stains. Br J Dermatol. 2002;146(3): 440–447. 

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Category: Original Research, Past Articles, Pigmentation disorders

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