Prolonged grief disorder in end-of-life care: current literature and future directions

Introduction

This review explores the current state of the field for prolonged grief disorder (PGD) research and treatment in the context of end-of-life care. End-of-life care can be considered the final stage of palliative care, which is defined as the active holistic support provided to individuals across all ages nearing death with serious health-related suffering due to severe illness, focusing on comfort, dignity, and relief from distressing symptoms rather than curative treatment (1). It also includes emotional and practical support for families and caregivers before and after the patient’s death. Bereavement care for family caregivers represents a crucial aspect of comprehensive end-of-life care (2). The emotional, psychological, and practical challenges that caregivers face do not end with the patient’s death; rather, the grieving process may often intensify during this period (3,4). Providing ongoing support helps caregivers process their loss, adjust to life after caregiving, and reduce the risk of mental health difficulties (5-7). Moreover, the provision of well-matched and timely support through both, social networks and professional care, is crucial to prevent the development of PGD in family members and caregivers (7,8). Hence, establishing an interaction between community networks and professional services is needed for effective and sustainable bereavement care (8). Currently this is a theoretical assertion and further research is needed to empirically evaluate the use of preventative interventions for PGD.

Atypical grief is a recognized distinct mental health disorder that is differentiated from normative grief processes and captured as a separate diagnostic category called PGD in the DSM-5-TR in 2022 and in the ICD-11 in 2018. In earlier versions of the ICD, atypical grief was classified under adjustment disorders. When symptoms of depression were bereavement-related, severe or prolonged, atypical grief was misclassified as depressive episodes. Similarly, the DSM-3 in 1980 included a bereavement exclusion for major depressive disorder (i.e., major depressive disorder should not be diagnosed within 2 months after loss) (9). In 2013, the DSM-5 introduced atypical grief as persistent complex bereavement disorder, a condition described as severe, enduring grief, but not formalised as a diagnosis (10).

Early contributions to precursor diagnostic sets include the PGD consensus criteria from Prigerson et al. (11), the criteria for complicated grief from Shear et al. (12) and the PGD criteria from Maercker et al. (13), which have shown more differences than similarities.

In current diagnostic sets, DSM-5-TR and ICD 11, PGD is characterized by core symptoms such as longing for and preoccupation with the deceased. Additional symptoms are emotional distress and functional impairment to a clinically significant degree that persist at least 6 months in the ICD-11 (14) and 12 months in the DSM-5-TR (15) following the loss of a loved one, with the duration and severity of the grief response being markedly greater than social, cultural, or religious norms for the bereaved person’s culture and context (11,16). Besides the criteria for time since bereavement, the diagnostic sets differ in the diagnostic algorithm, the number of symptom items and how precisely they are described.

Emotional distress is a common reaction among recently or imminently bereaved relatives and their grief reactions tend to decrease gradually. On the other hand, grief symptoms of bereaved individuals with PGD persist or worsen over time, which highlights the importance on providing bereavement care as a preventive measure and the need for continued support months after the death and beyond the hospital setting.

Taking into account the context and circumstances in end-of-life care, which characteristically include anticipatory grief as a source of distress for family members and caregivers (17,18) as well as illness and caregiving burden, the probability to develop PGD post-death of the patient is heightened, with one study identifying 28 out of 32 caregivers of terminally ill patients at risk for PGD during the period before death (19). Furthermore, caregivers with prolonged grief symptoms seem to want services but underutilize them (20). Thus, bereavement support in end-of-life care requires thorough assessment and intervention for the prevention of PGD in this population.

A pooled prevalence of PGD of 9.8% have been estimated in one review (21) with another review estimating average prevalence rates for PGD of 13% across 16 countries (22). Another study has estimated prevalence rates for PGD in line with the ICD-11 definition at 1.5% and at 1.2% for the DSM-5-TR definition in the German general population (23). The probability to develop PGD among bereaved individuals has been estimated at 4.2% for the ICD-11 definition and 3.3% for the DSM-5-TR definition, with high diagnostic agreement between the two criteria sets (23). The study further reported that over 60% of participants with probable PGD diagnosis utilized health care services and that difficulties accepting the loss was the most frequent single symptom. Another study estimated prevalence rates of PGD at 2.9% in bereaved individuals in a palliative care unit (24), and subthreshold PGD at 4%, with increased responsibility as a single parent after passing of a spouse being the only significant risk factor for PGD (24). Furthermore, an evaluation of the prevalence of PGD for bereaved cancer caregivers showed that around 20% of caregivers experience symptoms of PGD that persist three years post bereavement (25). It is important to note, however that prevalences of PGD are often based on self-reported symptomatology, without clinical interviewing, which potentially skew the estimation of prevalences (26). All in all, this further highlights the importance of screening caregivers after bereavement to deliver accurate support.

Risk and protective factors for PGD in end-of-life care

Various risk factors for the development of PGD in family members can be assessed to identify high risk individuals. One study in Japan examined the impact of quality of end-of-life care on PGD among bereaved family members (27). The findings showed that family members dissatisfaction with the way a patient’s expected outcome was explained to them, an unreasonable cost of care, and the family’s perception that the deceased person had not achieved a sense of completion about his or her life were significantly associated with possible PGD in bereaved family members. Other significant factors for possible prolonged grief were related to participants characteristics (i.e., spousal relationship, primary caregiver and high psychological distress). However, this study did not assess other important factors and the influence of these on potential PGD (e.g., attachment style and social support). Nevertheless, assessing perceived quality of end-of-life care as well as characteristics of bereaved family members can help us to detect and tailor intervention for bereaved family members. Among a general bereaved population, pre-death prolonged grief symptoms and depression were shown to be strongly associated with prolonged grief symptoms after the loss in a systematic review about risk factors for PGD symptoms (28).

Similarly, literature about risk factors for poor adjustment to bereavement in family caregivers suggests that high risk individuals can be assessed and provided with support that is aligned with their needs and their context (29-31). For instance, a qualitative study with 18 family caregivers of terminal-phase cancer patients found that certain caregiving elements experienced by family caregivers (e.g., communication problems between the patient and family caregiver, guilt of not being present at the time of death, family conflicts) were likely to influence their grieving process negatively (29). Other negative repercussions on adjustment with bereavement were observed with certain attitudes of the patient, such as denial of the illness and aggressiveness. Less preparedness for the caregiving role, greater impact of caring on schedule, relationship strain, lack of social support, lower active coping mechanisms, greater impact on caregiver’s health were shown to be risk factors for developing PGD in another study (32). Moreover, a longitudinal study showed significant risk factors of developing PGD during bereavement in family caregivers of cancer patients such as spousal relationship to the patient, greater impact of caring on schedule, and poor family functioning (31). In their study, a PGD rate of 11.3% was present in their sample 13 months after the death of the patient. Similarly, a review which examined grief reactions in dementia caregivers found spouse caregivers and higher levels of pre-death depression to be the strongest predictors for prolonged grief as well as typical grief after death (30), which is in line with a recent study linking pre-existing psychopathology with an increased risk of PGD (33). However, the review reported poor quality evidence about the prevalence of grief, with studies reporting anticipatory grief between 47% and 71%, and prolonged grief after death estimated around 20%.

All in all, PGD as well as risk factors for developing PGD seem to be frequently present in end-of-life care settings.

Screening and assessment

For the assessment of bereavement risk in the context of end-of-life care, three assessment points are considered ideal and have previously been proposed as before, during and after the death of the patient (6,34). A scoping review has summarized measures of bereavement risk and categorized them into pre-death measures, measures of bereavement risk following a patient’s death and measures of prolonged bereavement in palliative care following a patient’s death (34). Another review listed measures specifically used in end-of-life care (35), while another systematic review reported patient-reported outcome measures for anticipatory grief (36).

The first risk assessment would ideally be between the time when the patient receives end-of-life care and their death (34). During this time, family members and caregivers can show symptoms of anticipatory loss, which is defined as the feeling of loss being a threat or inevitable and any grief experience by the patient before death (37,38). As mentioned prior, pre-death prolonged grief symptoms are strongly associated with post-death PGD symptoms (28), highlighting the importance of pre-death measures of PGD for the development of post-death PGD. These pre-death measures can be assessed either by staff through observational checklists or through self-reports. Thirteen measures were reported that can be used before the death of the patient (34,36), of which two are observational checklists conducted by staff and can be used in end-of-life care settings (39,40), while 11 of the measures are conducted through self-report of caregivers (41-51). However, only the Bereavement Risk Index was reported as a measure for end-of-life care settings in Mularski et al.’s Review (35) and the Prolonged Grief-12 has been used specifically in end-of-life care settings (19).

The second assessment point for bereavement risk is ideally after the death of the patient to measure grief reaction (e.g., acute grief) in family members and caregivers (34). Acute grief is defined as separation response and response to stress that starts immediately after the death of a loved one (52). To assess grief reaction, 10 self-report measures of bereavement risk following a patient’s death were reported in the review (34,53-63). The Core Bereavement Items (53), Grief Evaluation Measure (54), Hogan Grief Reaction Checklist (55) and Grief Experience Inventory (56) have been specifically used in end-of-life care settings (35). Furthermore, the Bereavement Risk Screening Tool (BRST) can be used by clinicians and clinical social workers to identify family members at heightened risk for a poor bereavement outcome (64). Additionally, a short version of the Two-Track Bereavement Questionnaire mentioned in the review is available (65).

The third risk assessment point is at six months as most bereaved individuals experience long-term loss, and some might even experience symptoms of PGD. Bereaved individuals that were identified as being at risk during the preceding assessment points are ideally assessed again at six months and beyond with measures of PGD. PGD can only be clinically diagnosed six months after the loss. Reported measures of prolonged bereavement that could be used following a patient’s death are mostly based on self-reports (11,34,48,66-71). Additionally, the Traumatic Grief Inventory-Self Report Plus can be used as a measure for PGD that is in line with the DSM-5-TR and ICD-11 (72). For end-of-life settings, the Prolonged Grief-13 scale can be used (19,48), of which a revised version has been aligned with the current DSM-5-TR criteria (73). Furthermore, the International Prolonged Grief Disorder Scale (IPGDS) can be used to assess grief in relation to cultural expectations and norms as the scale includes a cultural supplement (74). The IPGDS has been validated across different cultural groups and languages (75-77). The International Grief Questionnaire is another newly introduced screening tool that is in line with ICD-11 criteria for PGD (78). See Figure 1 for a summary of all measures for the three assessment points.

Figure 1 Screening and assessment tools. *, developed for palliative care.

All these measures were developed for a variety of purposes but can be performed in the context of end-of-life care primarily by mental health clinicians (e.g., psychologist, clinical social workers, bereavement counsellors, specialist grief therapists), although certain informal screenings and observations can be performed by nurses and physicians to refer family members at-risk for specialist assessment. Additionally, video tutorials can help mental health professionals to accurately diagnose PGD (79). Only the Bereavement Risk Assessment tool and the Bereavement Risk Screening tool were specifically developed for palliative care (34,39,64). Furthermore, to diagnose PGD in health services across the world, a structured clinical interview that is consistent with the current definitions of PGD in ICD-11 and DSM-5-TR is necessary. For instance, the Aarhus Structured Clinical Interview, which is a diagnostic assessment tool that was developed and validated for ICD-11 and DSM-5-TR PGD (80).

Finally, family caregivers and bereaved family members appeared supportive of bereavement risk screening before and after a patient’s death with several suggesting multiple timepoints and the importance of follow-up in one study that conducted semi-structured interviews (81). Furthermore, risk screening was viewed as an opportunity to connect to psychosocial support.

Treatment and interventions

The current standard for bereavement care in end-of-life care varies worldwide with service provision located across different sectors and stakeholders. The three-tiered approach to enable needs-based service allocation provides a strong framework for bereavement care that would be a useful model for use worldwide (7,82). The three-tiered approach of bereavement care is included in the adult bereavement care pyramid with an additional tier and serves as a national framework (83). The first tier of this pyramid model suggest that all bereaved individuals have some level of need (e.g., compassion or acknowledgment of the death). Only some individuals need additional help outside of their natural network (e.g., peer to peer support) as reflected in the second tier, and in the third tier a few require more intensive support (e.g., counselling). The fourth and last tier reflects support from a specialist therapeutic service which is needed by a few bereaved individuals (Figure 2). Both, the three-tiered and the four-tiered model are similar except that the latter model has two distinct tiers for the middle level that capture additional needs in the second tier and more complex needs in the third tier. While some bereaved individuals require professional therapeutic services captured by the third tier, others only need a range of organized support (second tier). All in all, both approaches ensure well-matched and well-timed bereavement care according to the needs of bereaved individuals (7).

Figure 2 Adult bereavement care pyramid. Original source: The Adult Bereavement Care Pyramid: A National Framework (2020). Irish Hospice Foundation. Licensed under CC BY-NC-ND. Reproduced with permission.

Interventions

Grief support entails providing support to family members and caregivers throughout the experience of end-of-life care continuing after the person’s death into bereavement (84,85). Palliative care nurses are considered to play a pivotal role in offering bereavement support (tiers 1-2), able to offer general information and support as well as more targeted interventions to at-risk families (85-87). A scoping review thematically analyzed the aims of service-led bereavement care and found common themes such as providing a ’safety net’ being able to provide information and signposting as well as varying support interventions (88). Indeed, reviews have found that in specialist palliative care settings pre-death communication and support as well as post-death interventions (follow-up and support groups) have the potential of improving grief outcomes, and that families perceive these interventions as beneficial (2,89). Whereby information and communication could be representative of a tier 1 intervention, and post-death more targeted support represent level 2 interventions. It is important to note that although the first tier of the pyramid model suggests all bereaved individuals have some level of need, not all support is necessarily helpful. For instance, condolence letters two weeks post-death were associated with increased depression and post-traumatic stress disorder (PTSD) related symptoms and did not alleviate grief symptoms (90,91).

Existing literature shows limited preventive approaches for PGD in palliative care, with some evidence specifically in end-of-life care showing effective results using interventions tailored to specific contexts (i.e., meetings to family members before the death of their loved ones and afterwards) (92,93) as well as comprehensive communication during dying (85). Integrating support throughout the healthcare system (cancer care or intensive care unit) allows for successful continuity of care and support.

At the second tier, bereavement groups are common and provide emotional and social support, information, or facilitate exchange for all bereaved individuals (94,95). However, the evidence to support their effectiveness is weak as bereavement groups were marginally more effective than control groups only post-treatment (94).

At the fourth tier, targeted psychological therapies, and most commonly variations of Cognitive Behavioral Therapy (CBT) have shown significant effects in reducing PGD symptoms (96-98). The focus of CBT for PGD is the interplay of negative beliefs, memories and maladaptive coping strategies, such as avoidance. Exposure to avoided stimulus (such as memories, situations or people) is considered a key component of CBT for PGD, that creates meaningful change and reduces suffering (82,99,100). Cognitive restructuring and behavioral activation are other key components often found in CBT for PGD (101). In addition, CBT and family-based approaches have been found helpful for children and adolescents (102-105). Specific to palliative care, a newly developed psychological intervention called EMPOWER (Enhancing and Mobilizing the Potential for Wellness and Resilience) was developed to reduce the psychological distress of surrogate decision-makers of critically ill patients (106). EMPOWER is an ultra-brief 2 hour 6-module manualized intervention and seems to be feasible as 89% participants have completed all 6 modules. A preliminary feasibility study showed that EMPOWER was superior to enhanced usual care at reducing peritraumatic distress immediately post-intervention and grief intensity, posttraumatic stress, experiential avoidance, and depression 3 months post-intervention (106). Furthermore, the intervention seems to be acceptable with high ratings of satisfaction reported in the study and further showed higher surrogate satisfaction with overall critical care compared to enhanced usual care. Further testing and validation is required. Other therapies such as eye-movement desensitization and reprocessing, as well as mindfulness-based interventions, have some support, but more evidence is required (107,108).

Furthermore, there is a lack of evidence of bereavement care for minorities (109) and non-Global North cultures (110,111), who might hold different believes, traditions and expectations for mourning and bereavement care. Nevertheless, emerging research supports the applicability of CBT for PGD in these communities (111,112).

Implementation gap

Despite a growing body of literature and research-based recommendations around bereavement care practices, bereavement support continuity and integrated transition of bereavement care into community support is largely unachieved and not prioritized in end-of-life care as well as in general hospital care, intensive care unit (ICU) care, and home care (113-115). Currently provided transitional support is generic leading to limited helpfulness (116), which highlights the demand of transitional support that is tailored to personal factors (e.g., family situation) and specific needs of the individual. Although some healthcare providers are aware of national bereavement care guidelines (e.g., general practitioners), some do not base their services on these guidelines (117). Specialist support remains difficult to access (118), with a widespread lack of training and capacity of clinicians (89,118-120). However, health-promoting support is needed for all bereaved family members, even if specialist interventions might not be required in most cases.

There is an evidence–practice gap in bereavement care, which may stem from early studies that reported limited effectiveness of interventions (121). Although more recent reviews demonstrate growing evidence for bereavement care—reflecting improved interventions and research quality (2,85)—current policies and practices remain only moderately evidence-informed rather than strongly evidence-based (122). As a result, evidence-informed recommendations have not translated into population-level impact, highlighting the need for implementation science approaches to bridge the gap between research, practice, and service provision (121). A scoping review reported factors that support or hinder implementation of palliative care guidelines globally using the Petermann’s taxonomy (123). Although the overall results of the review were highly heterogeneous, integrating a measure into the relevant institutions (penetration), implementing the guideline as specified in the recommendations (fidelity/adherence) and the extent a guideline is perceived as satisfactory (acceptance) are among the most common implementation outcomes examined (124). The review further reported facilitators of and barriers to implementation of palliative care guidelines (Figure 3). Other studies reported insufficient training, lack of privacy with families as well as lack of time and organizational support as the most often named barriers for hospital-based bereavement care provision (125,126). In line with this, a review reported barriers to be lack of communication with the patients, caregivers, physicians and palliative care team about program goals, stigma around the term “palliative”, a lack of training or awareness of guidelines and undefined staff roles (127). Furthermore, viewing the deceased as well as giving information on available support were the most frequent bereavement services reported in one study (125).

Figure 3 Bereavement care pyramid with barriers to and facilitators of guideline implementation. Established process refers to needs and services described in the four-tiered approach of bereavement care (84) mentioned earlier.

However, bereavement care has been criticized as being inadequate with resources being scarce (89,121,128), with Boven et al. [2022] describing it as occurring in an act of ‘good-will’ from staff members. In addition, care professionals have expressed uncertainty about how to best support caregivers through bereavement (128).

Digital interventions

With access to mobile phones increasing dramatically over the last years, digital mental health interventions have gained popularity (129,130). Digital interventions promise increased accessibility, reduced stigma, anonymity and flexibility (130) and have thus been suggested to partially close the treatment gap for bereavement care (118). Meta-analyses of web-based intervention studies for bereaved individuals have reported medium treatment effects (131,132). However, Internet-based therapy could be particularly useful for populations where grief is disenfranchised or stigmatized (133,134).

Digital interventions that help family caregivers with managing the symptoms of a family member in end-of-life care can help with their overall satisfaction with the quality of end-of-life care the patient received (tier 1) (Figure 3). This in turn can positively influence the family caregivers grieving process post death of the patient as mentioned earlier (29). One study has examined the efficacy of an automated mHealth platform for caregivers managing symptoms of end-of-life family members with cancer during home hospice care (135,136). This intervention included caregiver coaching on patient symptom care and nurse notifications of poorly controlled symptoms and showed a significant mean overall symptom reduction benefit compared to usual hospice care.

At the second tier, a study tested the intervention named ACCESS (Access for Cancer Caregivers to Education and Support for Shared Decision Making) which uses private Facebook groups to support and educate caregivers and further prepare them to participate in shared decision-making during web-based hospice care plan meetings (137). The study reported that the ACCESS intervention did not significantly decrease depression compared with the enhanced usual care group. In contrast, a meta-analysis reported that online bereavement support was feasible, acceptable and effective in reducing grief intensity, stress-related outcomes and depression, with access to a supportive community at any time, reduced isolation, opportunities to process feelings, normalization of loss responses and access to coping advice along with opportunities for meaning-making and remembrance being positive impacts (138). However, negative impacts such as upset due to insensitive comments from others via unmoderated online forums was reported in the meta-analysis.

Another text-based online grief intervention that offers support is help texts, formerly known as Grief Coach (139,140). The program delivers text-message based reminders, informational support and tips. Uniquely, it also delivers these to any ’supporters’ (friends or family) who sign up. The content is personalized by referring to the griever, supporter and deceased by name and by tailoring the messages to the griever’s relationship to the deceased amongst other characteristics. In a US based study, grief coach was offered to 350 families for 12 months, free of charge (139). Thirteen-month retention rates were high (86%), with thirty-nine percent of grievers enrolling supporters. Among those responding to the survey (65%), most participants reported finding it very helpful (73%) and as contributing to their feeling of being supported (74%). In an even bigger study of 4000 enrolled grievers in the UK, retention rates were reported similarly high (85% at 12 months). Similarly, amongst those who completed the survey (56%), ninety-five percent rated grief coach as moderately or very helpful. However, it is important to note that retention was calculated based on whether participants unsubscribed or could otherwise not be reached. Engagement with the content was not measured.

At the fourth tier, internet-based CBT for PGD has been shown to be effective in unguided (141-143) and therapist assisted formats (144). New and emerging app-based interventions for grief offer increased flexibility and real-time use (130,145). One such intervention is the My Grief app for bereaved parents (146,147). The app is based on CBT and consists of four sections: daily grief monitoring, psychoeducation, exercises (including mindfulness, relaxation techniques and exposure to memories of the loss) and a ‘get support’ section with signposting and social networking information. In a small pilot study (N=13), participants used the application for 4 weeks. The authors concluded that the intervention showed sufficient feasibility and acceptability (146). The authors found significant reductions in prolonged grief symptoms, grief related rumination, loss avoidance and negative cognition. Importantly, only ten participants filled out the follow-up survey, of which nine were female. In addition, five participants scored above the threshold for probable PGD at baseline. In a bigger randomized controlled trial, 67 participants completed 3 month use of the app, and reported that they found the app helpful in increasing their knowledge of grief (70%), making them feel like there was something they could do about the grief (69%), making them comfortable in seeking additional help (147), and that they would recommend it to other parents in a similar situation (63%). 52% of participants reported using the app less than once a week, and 40% reported using it once or a few times a week. Participants reported that it would have been more helpful at the beginning of their grief journey.

Overall, the evidence base for CBT is strongest with other treatment presentation and interventions still emerging.

Limitations of current diagnostic measures of PGD

Current diagnostic measures for PGD commonly utilize validated retrospective self-report instruments which have shown psychometric robustness (e.g., Traumatic Grief Inventory-Self Report Plus, PG-13, Structured Clinical Interviews). Nevertheless, retrospective self-report instruments generally are marked by methodological shortcomings (148) and rely on the individual’s memory recall and introspection. Factors that drive behavior are largely invisible to the individuals that display it (148,149) and the risk that the individual fails to recall their experiences is increased by the artificial laboratory context they are assessed in (e.g., research lab instead of the natural context the experiences occur in) (150). Furthermore, individuals’ self-reports are not only shaped by accuracy but also other motives such as self-representation that can result in socially desirable responding (151). These general limitations of self-report instruments are not exclusive to PGD but also other mental health disorders that rely on self-report instruments. The use of these influence the accurate and timely assessment of potential symptoms of PGD and the timely provision of treatment by not enabling a direct observation of the individual in their natural day to day life (150).

Ecological approaches to detect early factors of PGD

Ecological Momentary Assessments (EMA) have been frequently used for the assessment of mental health symptoms in recent years and show a potential for the diagnosis of PGD symptoms. EMA, also known as Experience-sampling method (ESM), is one method for studying daily life among two other approaches, namely the Electronically Activated Recorder (EAR) (152) and Mobile Sensing Methods (MSM) (150). These methods of studying daily life are ecological, meaning that they are implemented in the natural environment of the individual. Compared to the other two methods, ESM is actively assessed through self-reports with the individual receiving prompts with microbursts of assessments (e.g., through their phone or computer) during a window they are most likely vulnerable (e.g., experiencing symptoms) and receptive to be assessed. By using ESM, an individual does not have to rely on memory recall and, therefore, is assessed more accurately. ESM has been used in recent studies to assess grief symptoms in bereaved people (153-156). However, other limitations of self-reports remain.

Literature indicates the lack of timely provision of intervention (e.g., during pre-death grief) and certain risk factors, such as closeness to the deceased or the circumstances of the loss (natural vs. unnatural/ violent death), to be associated with atypical grief and reasonable drivers for the development of PGD (28). Biomarkers for PGD are still largely unexplored but might be an innovative approach for prevention. The EAR collects raw audio data in the individual’s day-to-day life which enables behavioral observation (152). Similarly, the MSM collects sensor metadata (e.g., accelerometer senser, call logs, chat logs, location, light sensor) passively through the mobile phone (150) or other devices such as wearables, which can assess additional physical data (e.g., heart rate variability, sleep disturbances). Both methods are unobtrusive and passive approaches for observing the individual’s direct behavior and address the limitations of self-reports. With time, consistent behavioral patterns collected through digital devices can be observed in certain groups. For instance, Robbins et al. have observed that sighing is significantly related to patients’ levels of depression through the EAR (157). In another systematic review about the relation between passively collected data and PTSD, relative amplitude of physical activity and wake after sleep onset were found significantly correlated with PTSD symptoms (158).

Importance of early detection in end-of-life care

Exploring the connection of objective and physical data that is collected passively with self-reported grief-related symptoms that are collected actively can define biomarkers for PGD and ultimately help establish a digital phenotype. Digital phenotyping uses a collection of smartphone data (e.g., sensor, keyboard, and voice and speech) to measure behavior, cognition, and mood in a group (159). For instance, a systematic review found significant digital phenotypes for depression (e.g., lower mobility and social interaction were associated with higher depression symptoms) and showed moderate success across various prediction goals (160). Another systematic review about the current state of digital technologies has reported the use of digital phenotyping for PTSD in three studies (161-164). All three studies used smartphones to collect data for PTSD diagnostic prediction (163,164) as well as PTSD and depression symptom prediction (162). By establishing a digital phenotype for PGD, risk factors can be detected, and intervention protocols triggered early, even in palliative care units. Risk factors that are associated with the development of PGD can be detected in end-of-life care even before the loss occurs, with physicians and nurses introducing the correct intervention protocols in advance.

Most mental health issues manifest early on, sometimes even before the individual is aware of them. Physical changes and changes in behavioral patterns, such as sleep disturbances (165) and cardiovascular problems (166) which were shown to be correlated with elevated PGD symptoms, can be monitored with wearables, such as fitbits, and smartphones, making diagnosis and treatment accessible to individuals outside of WEIRD populations (Western, educated people from industrialized, rich, democratic countries). Risky behaviors associated with elevated risk of mortality rate in this population (e.g., substance use) (167) can be monitored to provide a Just-In-Time Adaptive Intervention (JITAI) for individuals. A JITAI is an intervention that is personalized to an individual’s needs (e.g., internal and contextual state), provided at the right time and contains the right type and amount of support (168). Furthermore, using digital phenotypes in different cultural contexts could enable an accurate depiction of typical and atypical grief trajectories in different cultures over time.

Conclusions

Bereavement care must be recognized as an essential component of comprehensive end-of-life policy, requiring the formal inclusion of PGD screening, evidence-based interventions, and clear guidelines that incorporate both traditional and digital modes of grief support. Strengthened policies should prioritize funding and resource allocation for caregiver mental health, professional training, and responsible digital innovation.

Within clinical practice, routine assessment of risk factors for PGD among family caregivers—both during the end-of-life phase and after the patient’s death—should become standard. Holistic bereavement support is best achieved through interdisciplinary collaboration across palliative care, mental health, and social work, ensuring that care plans are culturally sensitive, individualized, and attentive to relational, spiritual, and social dimensions of grief.

Integrating digital tools such as online therapy platforms, mobile applications, and virtual support groups can extend the reach and accessibility of care, especially for those who face logistical or emotional barriers to in-person support. Effective implementation requires embedding PGD screening and bereavement interventions into existing workflows, supported by clear protocols and adequate training for staff to use digital technologies safely, ethically, and efficiently. Implementation planning must also anticipate barriers and address them with solutions such as blended models that combine technology with human support. Monitoring and evaluation frameworks are crucial to assess outcomes, equity, and real-world effectiveness, and to guide continuous improvement.

Looking ahead, innovation in bereavement care will benefit from pilot programs and research that tests scalable, technology-supported grief interventions. Policies should support continuity of care beyond the patient’s death, ensuring structured follow-up and ongoing support for caregivers. Ultimately, future models of bereavement care must be adaptable, sustainable, and grounded in thoughtful integration of both human and technological resources.

Acknowledgments

None.

Footnote

Provenance and Peer Review: This article was commissioned by the Guest Editor (Alexander Gamble) for the series “Integration of Palliative Care and Mental Health Services” published in Annals of Palliative Medicine. The article has undergone external peer review.

Peer Review File: Available at https://apm.amegroups.com/article/view/10.21037/apm-2025-1-148/prf

Funding: None.

Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://apm.amegroups.com/article/view/10.21037/apm-2025-1-148/coif). The series “Integration of Palliative Care and Mental Health Services” was commissioned by the editorial office without any funding or sponsorship. The authors have no other conflicts of interest to declare.

Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.

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