The stigma of digital amputation: a survey of amputees with analysis of risk factors

The purpose of this study was to quantify the stigma associated with digital amputation and examine factors associated with it. One hundred and sixty-four digital amputees completed the Neurological Quality of Life-Stigma questionnaire and a battery of Patient-Reported Outcome Measurement Information System instruments. Multivariable analysis examined factors associated with stigma experience. The mean observed stigma score of 47 (SD 8, range 36–64) was similar to the mean value of the normal population. Younger age, a worker’s compensation claim and depression were each independently associated with a more severe experience of stigma after digital amputation. Socioeconomic variables, anatomical details and mechanism of injury were not independently associated with stigma. Digital amputation is not highly stigmatizing overall. Surgeons should consider referring at-risk patients to a mental health provider for support during the coping and adjustment process after amputation. Level of evidence: III

Surveys of patients with stigmatizing conditions are an important part of understanding their stigma experience (Carlozzi et al., 2019;Ma et al., 2016).
However, previous studies of digital amputation stigma have been limited to surveys of surgeons and the general non-amputee public regarding expectations and assumptions surrounding a theoretical amputee's experience (Maroukis et al., 2016;Nishizuka et al., 2015;Shauver et al., 2016).
The primary aim of this study was to quantify the stigma associated with digital amputation using information gathered directly from digital amputees using the Neurological Quality of Life (Neuro-QOL)-Stigma patient-reported outcomes (PRO) instrument. This is a computer adaptive test (CAT) that measures the combination of enacted and internalized stigma (Molina et al., 2012;Rao et al., 2009). Although it was designed for patients with neurological diseases, it has been more broadly applied, including to patients with upper extremity conditions (Maroukis et al., 2016;Nishizuka et al., 2015;Shauver et al., 2016). We aimed to examine factors associated with the experience of stigma, and how stigma correlates with other psychosocial and functional outcomes. Our primary hypothesis was that digital amputees would report more stigma than the general population, and that age, mental health conditions and severity of injury would affect the degree of stigma experienced.

Methods
This was a descriptive retrospective cohort study of digital amputees. After receiving approval from the Washington University in Saint Louis School of Medicine institutional review board, Current Procedural Terminology and International Classification of Diseases databases were queried for all patients undergoing digital amputation or revision amputation between April 2010 and April 2020. Medical records were reviewed for age at amputation, gender, indication for amputation, laterality, level and number of amputated digits. Depression that preceded the amputation (as evidenced by a formal diagnosis or documentation of a prescription for that indication) was recorded from the chart. The patient's home address was used to determine their area deprivation index (ADI), a measure of socioeconomic disadvantage and deprivation that has been used in several upper extremity outcomes studies (Bernstein et al., 2019;Kind and Buckingham 2018;Okoroafor et al., 2018;Stirling et al., 2020;University of Wisconsin, 2018;Wright et al., 2019aWright et al., , 2019b. A higher ADI score represents greater deprivation. The inclusion criteria for study enrolment were one or more digital amputations sustained within the study period and age ! 18 years at the time of survey. Eligible patients were contacted by telephone. After a scripted explanation of the study, it was requested that each patient complete a battery of electronically administered PRO questionnaires. Patients who were deceased or could not be contacted, unwilling or unable to receive the PRO questionnaires, unable to provide informed consent and those who were unable to comfortably communicate in English were excluded. Consenting patients provided an email or cellular phone number by which they could receive a personalized and secure link to the study PRO instruments, which were administered remotely. The CAT questionnaires administered in this study were: Neuro-QOL Stigma v1.0 (CAT item bank available in Appendix S1, available online); Patient-Reported Outcome Measurement Information System (PROMIS) Anger v1.1; PROMIS Anxiety v1.0, PROMIS Depression v1.0; PROMIS Upper Extremity Function v2.0 (UE); PROMIS Ability to Participate in Social Roles and Activities v2.0; and PROMIS Pain Interference v1.1. A short additional questionnaire recorded handedness, ethnicity, education level and worker's compensation (WC) status. All PRO instruments used in this study have a reference population mean of 50 and standard deviation of 10, with higher scores indicating more of the factor being measured. For example, a Neuro-QOL Stigma score of 60 is one standard deviation in excess of the reference population mean and represents a high-stigma experience. Although we did not modify the Neuro-QOL instrument, which uses the broad term 'illness', we did provide a sentence at the beginning of the instrument to clarify that stigma questions were specifically in reference to the digital amputation.

Statistical methods
Explanatory variables were treated as dichotomous, interval or continuous. Continuous variables were tested for normal distribution using the Shapiro-Wilk test. Normally distributed data are presented as mean (standard deviation; range) and data that are not normally distributed are presented as median (interquartile range; range). Education was dichotomized (0 ¼ less educated; 1 ¼ more educated) based upon whether or not the patient had completed an Associate's degree (2 year collegiate) or higher. The most proximal amputation level was dichotomized (0 ¼ distal; 1 ¼ proximal) based upon preservation (or loss) of the proximal interphalangeal joint in fingers and preservation (or loss) the proximal phalangeal head in thumbs. Comparison of means was accomplished using the two-tailed Student's t-test for normally distributed variables and the Mann-Whitney U test for non-normally distributed variables. Intergroup comparison of proportions was accomplished using the chi-squared test. Bivariate relationships between all explanatory variables and the primary outcome variable (Neuro-QOL Stigma) were assessed using linear regression. Explanatory variables with bivariate p-values 0.2 were entered into the multivariable regression. Multivariable analysis was achieved using stepwise regression. Correlation between primary and secondary outcome variables was assessed using Pearson's r. Statistical significance was defined as p < 0.05.
An a priori power calculation revealed that to obtain 80% power for detection of a moderate effect size (f 2 ¼ 0.15) (Cohen, 1988;Soper, n.d.) in a multivariable analysis with up to ten independent variables entered into the model, a minimum sample of 118 participants would be required.

Results
The database query yielded 1101 patients with qualifying amputations. The excluded patients are detailed in Figure 1. One hundred and sixty-four (15%) patients ultimately completed follow-up questionnaires. Demographic and injury details for the groups with completed PROs and those without are compared in Tables 1 and 2. Compared with patients who did not participate, the surveyed group was older, more likely to be white, less deprived and with more recent amputations. Women and non-WC cases were over-represented in the group with complete follow-up. Fifteen of the 164 (9%) patients had a diagnosis of depression at the time of amputation. The mean Neuro-QOL Stigma score in the follow-up cohort was 47 (SD 8; range 36-64). A histogram of Neuro-QOL Stigma scores for the sample is shown in in Figure 2.

Patient and injury factors associated with stigma experience
Bivariate analysis (Table 3) revealed that among all explanatory variables, younger age at amputation, higher ADI, less education, WC status and a diagnosis of depression at the time of amputation were associated with a significantly worse stigma experience after digital amputation. Gender, number of amputated digits, thumb involvement, amputation level, dominance of the injured side and mechanism of injury were not associated with Neuro-QOL Stigma. Because the responding population was overwhelmingly (89%) white, the role of ethnicity could not be analysed.
Seven explanatory variables (age at amputation, ADI, education, depression, number of amputated digits, dominance of the injured side, WC status) had bivariate p-values 0.20 and thus met criteria for entrance into the multivariable model. Multivariable analysis (Table 4) revealed that of the seven explanatory variables entered into the stepwise regression, only three had independent associations with more severe stigma experience: younger age, a WC claim and a diagnosis of depression at the time of amputation.

Relationship between Neuro-QOL Stigma and secondary outcome measures
The primary outcome variable (Neuro-QOL Stigma) was found to have statistically significant relationships with other measures of patient outcome

Discussion
The observed association between younger age and an increased perception of stigma is consistent with the National Survey for Midlife Development, in which a significant interaction between stigma and younger age was observed (Bookwala, 2017). With increasing age, individuals are more strongly motivated to regulate their emotional well-being, and thus may deemphasize potentially stigmatizing experiences and show greater emotional resilience (Bookwala, 2017;Carstensen et al., 1999). Naushad et al. (2018) observed that patients with chronic pain and depression reported greater painrelated stigma than patients with chronic pain alone, and concluded that 'the presence of depression appears to be associated with greater experience of non-depression related stigma'. Although the reason  for this association is not fully understood, they found that depression was associated a greater need for patients to hide their condition and made them more likely to perceive experiences as stigmatizing.
In addition to digital amputation, WC cases have been associated with poor PROs in a variety of upper extremity conditions (Fujihara et al., 2017;Murgatroyd et al., 2015). It has previously been argued that when an outside agency plays a large part in the administration of care, patients are encouraged to remain in the sick role (Shifflett et al., 2012), which could include a perception or over-reporting of stigma, or both.
Contrary to our hypothesis that functionally and aesthetically severe injuries would be associated with increased stigma, we detected no effect from the number of amputated digits, level of amputation, involvement of the thumb, mechanism of injury or dominance of the injured side. We interpret this to mean that intrinsic patient factors are the primary drivers of the stigma experience in digital amputees, rather than anatomical or injury factors.
In this study, stigma was found to co-occur with other negative PROs including PROMIS measures of pain interference, depression, anxiety, anger, ability to participate in social roles and activities and upper extremity function. This is consistent with existing evidence that stigma is associated with other negative outcomes (Molina et al., 2012) probably reflecting that these outcomes share similar risk factors.
The most substantial limitation of this study is incomplete follow-up, primarily due to inability to contact many of the patients, with a resultant response bias. The limited enrolment is related to the 10-year range of eligibility for inclusion, which increases the likelihood of outdated contact information. Compared with non-participants, those enrolled in the study were more likely to be female, white, older, less socioeconomically deprived, recently amputated and uninvolved in a WC case. This is generally in line with the findings of previous studies, which indicate that younger age, being male and low income are predictive of survey non-response (Berlin et al., 2018;Massey and Tourangeau, 2012). The fact that 89% of respondents were white indicates that conclusions cannot be confidently generalized beyond this group. Given the reported negative associations with digital amputation in Eastern cultures (Maroukis et al., 2016) it would be illuminating to gather similar data in Asian and Asian-American populations.
Because this study lacked a non-amputated control group, we are limited in our ability to assess how the experience of stigma in digital amputees differs from that of non-amputees. Fortunately, this limitation is mitigated by the design of the Neuro-QOL Stigma scale that is centred around a reference population mean of 50. Detection of depression preceding amputation by way of chart review is a method that has been used in similar studies (Cochrane et al., 2020), but cases could have been missed. Also, because 90% of patients in this study had amputations of only one or two fingers, it is possible that we failed to detect an effect from more severe injury patterns involving more than two fingers. It should be noted that the Neuro-QOL Stigma scale was designed for neurological conditions and has not been specifically validated to measure stigma associated with digital amputation. Despite this, the questionnaire contains no condition-specific language and elements of this questionnaire have been used in previous studies focused on digital  amputation (Maroukis et al., 2016;Nishizuka et al., 2015;Shauver et al., 2016). Overall, the level of stigma experienced by digital amputees is relatively low. Our data suggest that the experience of stigma depends more on who the patient is than what happened to their hand. Although discussion about coping with physical stigma would seem to be appropriate in patients with more severe injuries, our findings suggest that attention should be focused on young digital amputees who are depressed or involved in a WC case, or both. In these patients the surgeon should consider referral to a mental health provider who can offer treatment for depression and support the process of coping and adjustment. Future studies should examine the stigma experience of digital amputees in different cultures, investigate what specific measures can be used to improve the outcomes in at-risk patients and investigate how digital replantation affects the experience of stigma.

Declaration of conflicting interests The authors
declare no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
Funding The authors disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: Dr Pet has received research funding from Checkpoint Inc. for unrelated work. Other authors have nothing to disclose. No funding was received for this article from any source.

Ethical approval The Washington University School of
Medicine Institutional IRB has approved this study (Approval # 202005045).
Informed consent Verbal informed consent was obtained from all subject before the study.
Contributorship MP conceived of this study. CM and CB obtained ethical approval and worked on protocol development. JD, EG, EP, LV, CB, and CM performed patient chart review, contacted patients by phone, and coordinated survey distribution. MP did statistical analysis. CB and MP wrote the first draft of the manuscript together. All authors reviewed and edited the manuscript and approved the final version of the manuscript.