Post-ICU Syndrome and Social Determinants of Healths

Post-ICU Syndrome: Exploring the Role of Social Determinants on Trajectories and Outcomes

Medical intensive care has improved dramatically, and today, 70% to 80% of critically ill patients survive. However, several survivors face long-term psychological, cognitive, and/or physical sequelae after discharge and challenges in resuming their lives. These conditions are known as Post-Intensive Care Syndrome (PICS). PICS is a multifaceted disorder that affects many patients who survive critical illness and receive treatment in the ICU. 'It can persist for weeks, months, and years after discharge, negatively affecting the quality of life of survivors and their families, generating financial consequences, and increasing the utilization of healthcare services. It can persist for weeks, months, and years after discharge, negatively affecting survivors' and their families' quality of life, creating financial burdens, and increasing healthcare utilization. Researchers have identified several PICS risk factors linked to sociodemographic and psychosocial conditions, including social support, isolation, and survivors' social position. Taken together, these findings highlight the role of social determinants of health (SDH) in explaining PICS and the different outcomes among survivors. We propose that applying an SDH framework can enhance understanding of PICS, its determinants, trajectories, and outcomes. Consequently, this study aims to examine the trajectories of PICS among ICU survivors and the role of SDH, including sociodemographic factors, social support, loneliness, perceived social position, among other factors, as well as the role of biomarkers and ICU treatments.

We will conduct a longitudinal cohort study with 400 patients from 5 different ICUs in Chile who received critical care. We will assess patients using sociodemographic factors, ICU treatment, SDH measures, psychosocial factors, biomarkers, and PICS symptoms at discharge and at 3, 6, and 12 months. Latent class analysis (LCA) will identify distinct latent profiles based on patterns of PICS symptoms. We will then examine social determinants of health (SDH) as covariates to determine whether they are associated with different profiles. These results will contribute to our understanding of PICS and inform interventions to prevent it and support the recovery process among survivors.

Study Overview

• Status: Recruiting
• Conditions: Post-Intensive Care Syndrome (PICS)

Detailed Description

In recent decades, advances in intensive care have substantially reduced mortality, with survival rates now ranging from 70 to 80% among critically ill patients. However, a considerable number of these survivors experience persistent sequelae after discharge from the intensive care unit (ICU), affecting their functionality, well-being, and ability to resume their everyday life. This set of sequelae has been conceptualized as Post-Intensive Care Syndrome (PICS), defined as the onset or worsening of physical, cognitive, and/or mental health impairments that develop after ICU hospitalization and persist beyond hospital discharge (Needham DM, et al., 2012). PICS is a complex, multifactorial condition that can last for months or even years, significantly impacting the quality of life of survivors and their families (Harvey MA., 2016). PICS encompasses a wide range of clinical manifestations. Physically, patients may experience muscle weakness, joint stiffness, decreased mobility, persistent fatigue, and difficulty performing activities of daily living. Cognitively, memory impairment, difficulty concentrating, deterioration of executive functions, and reduced attention span have been reported. Some patients also develop ICU-associated delirium, characterized by confusion, disorientation, and mental status changes. Symptoms of anxiety, depression, post-traumatic stress disorder (PTSD), and sleep disturbances are commonly reported psychological symptoms. These sequelae can reduce overall functional capacity, make it harder to return to work, and lead to loss of independence and impaired social participation, directly affecting the quality of life of patients and their caregivers. Prospective studies have shown that the consequences of PICS extend beyond the clinical setting, affecting occupational, social, and economic dimensions. In a UK cohort, one-third of survivors lost their jobs or retired within six months of discharge, and this proportion remained high at 12 months. In addition, a significant proportion required assistance with self-care, usually provided by family members, which negatively affected caregivers' employment and income. Persistent pain and fatigue were associated with a lower probability of returning to work.

Although PICS is highly prevalent, estimates vary considerably by population, definitions used, and timing of assessment after ICU discharge. Nevertheless, available evidence suggests that between 50% and 70% of intensive care survivors present one or more symptoms consistent with PICS; approximately six out of ten patients continue to experience at least one sequela a year after discharge. Physical impairments affect between 30% and 80% of patients, while cognitive impairment has been reported in ranges from 25% to 75%. In terms of mental health, the prevalence of anxiety and depression varies between 20% and 50%, and PTSD symptoms affect up to 20-30% of survivors. In addition, 30% to 60% have limitations in performing activities of daily living and reduced functional capacity, highlighting the magnitude of PICS's impact on long-term recovery.

Several risk factors for developing PICS have been identified, including advanced age, female gender, the presence of previous comorbidities, and lower educational or socioeconomic status (Brown SM., 2019). More broadly, these risk factors point to the relevance of social determinants of health (SDH), defined as the conditions in which people are born, grow, live, work, and age, as well as the social, economic, and political systems that shape these conditions (Braveman P., 2014), which are closely linked to health inequalities. Within this framework, perceived social position, an individual's subjective standing relative to others in society, distinct from objective indicators such as income or education, has emerged as a key determinant: survivors in lower social positions tend to present worse outcomes than those in higher positions (Jain S., 2022). This is explained because social position translates into psychosocial factors such as social support, loneliness, and chronic stress, which are associated with the worst health outcomes.

Consistent with this perspective, research findings suggest that psychological and social factors play a central role in the development and persistence of PICS. The ICU experience can be traumatic, and post-discharge stressors-such as loss of independence, financial difficulties, and caregiving overload-can perpetuate symptoms. The negative impact on the health outcomes of survivors may be intensified due to the psychosocial conditions associated with the SDH, already present before hospitalization in the ICU; anxiety, depression, or PTSD during hospitalization, as well as a history of mental illness, increases the risk of persistent psychological sequelae.

In summary, despite the growing body of research on post-intensive care syndrome (PICS), it remains defined as a set of symptoms, despite the heterogeneity of the disorders patients present with. This approach limits our understanding of the condition and the design of interventions, as PICS encompasses multiple combinations of symptoms and trajectories of evolution. Identifying patient groups with different symptom profiles, along with associated factors and their evolution over time, can provide researchers and clinicians with the input needed to advance our understanding. Recognizing the influence of psychosocial factors described in the SDH model on post-ICU outcomes represents a promising avenue to advance this knowledge, building on available evidence, although mostly descriptive, that psychosocial factors contribute to PICS outcomes. Understanding how social determinants relate to different symptom patterns and trajectories would help identify intervention points to reduce the impact of social conditions on recovery. Consequently, this study seeks to deepen understanding of PICS, provide evidence for intervention design, and contribute to improving long-term outcomes and quality of life for ICU survivors, while also reinforcing efforts to optimize post-ICU care and attention to the sequelae of critical illness.

Chile is a particularly relevant setting for studying SDH and PICS, as marked disparities in health outcomes between social groups persist despite reforms aimed at reducing inequalities. Fragmentation of the healthcare system between the public and private sectors, together with high levels of socioeconomic inequality, could significantly influence recovery after ICU hospitalization (Subramanian SV., 2003; Núñez A., 2020; Severino R., 2022). Inequalities translate into psychosocial factors, such as chronic stress and social support, that reflect individuals' social position within society.

This study examines the role of social determinants of health in post-ICU syndrome (PICS) symptoms, symptom profiles, and health outcomes among critically ill survivors. We also aim to (1) determine the prevalence of overall PICS, physical, cognitive, and mental health symptoms at all four data collection times, and associated risk factors; and (2) identify latent profiles of PICS symptoms and whether psychosocial determinants are associated with membership in these profiles.

To address the study aim, we will conduct a multicenter, prospective observational cohort study of 400 survivors, followed up to 12 months post-discharge from ICU. We will recruit eligible patients from five hospitals in Chile.

We will evaluate physical, cognitive, and mental health impairment. We will also evaluate quality of life related to health, frailty, fatigue, chronic pain, and sleep impairment. Social Determinants of Health will be evaluated using different measures: social position, household socioeconomic status, chronic stress, perceived stress, social support, loneliness, and sociodemographic and previous health conditions.

We expect to recruit 400 patients over the 4-year study period.

• Study Type: Observational
• Enrollment (Estimated): 400

Contacts and Locations

• Study Contact: Name: Paula B Repetto, PhD; Phone Number: +56223549024; Email: prepetto@uc.cl
• Study Contact Backup: Name: Leyla M Alegria, PhD; Email: lmalegri@uc.cl

Study Locations

• Chile
  • Quillota, Chile
    • Active, not recruiting
    • Hospital Biprovincial de Quillota
  • Santiago, Chile
    • Recruiting
    • Complejo Asistencial Dr. Sótero del Rio
    • Contact: Carolina Ruiz, MD; Email: ccruiz@uc.cl
  • Santiago, Chile
    • Recruiting
    • Hospital Clínico UC Christus
    • Contact: Leyla Alegria, RN, MSc, PhD; Email: lmalegr@uc.cl
  • Santiago, Chile
    • Recruiting
    • Clínica San Carlos de Apoquindo
    • Contact: Celia Flores, RN; Email: cfloresb@ucchristus.cl
  • Talcahuano, Chile
    • Active, not recruiting
    • Hospital Las Higueras

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Probability Sample

Study Population

Patients aged 18 years or older with critical illness who have been on a ventilator for at least 48 hours will be invited to participate in the study.

Description

Inclusion Criteria:

• Patients 18 years of age or older
• Patients with critical illness who have been on a ventilator for at least 48 hours

Exclusion Criteria:

• Presence of mental or intellectual disability before hospitalization
• Early limitation of therapeutic effort
• Primary neurological injury (e.g., anoxic injury, stroke, or traumatic brain injury)
• Anticipated death within 3 months of discharge (e.g., recommended palliative care)
• Uncontrolled psychiatric illness at hospital admission
• Communication limitations (e.g., does not speak Spanish)
• Unlikely to adhere to follow-up (e.g., no fixed address, difficult to locate at follow-up)

Study Plan

How is the study designed?

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Cognition status post-ICU	The MOCA instrument will be administered to patients. The total possible score is 22 points; a score of 18 or above is considered normal	From enrolment to the third, sixth, and twelfth months post-discharge from ICU
Anxiety post ICU	This mental health condition will be evaluated in patients with the HADS total scores for anxiety ranging from 0 to 21, categorized as: normal (0-7), mild (8-10), moderate (11-14), or severe (15-21).	From enrollment to the third, sixth, and twelfth months post-discharge from ICU
Depressive symptoms post-ICU	This mental health condition will be evaluated in patients with HADS total depression scores ranging from 0 to 21, categorized as: normal (0-7), mild (8-10), moderate (11-14), or severe (15-21).	From enrollment to the third, sixth, and twelfth months post-discharge from ICU
Functional independence post-ICU	Barthel will be used in patients; scores are ordered as follows: 0-20 total dependence, 21-60 severe dependence, 61-90 moderate dependence, 91-99 slight dependence, and 100 independence.	From enrollment to the third, sixth, and twelfth months post-discharge from ICU

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Health-related quality of life	EQ-5D is one of the most widely used health state descriptive systems and is used for valuation in Chile. EQ-5D questionnaires have 5 dimensions: "Mobility", "Human Autonomy", "Current Activities", "Pain / Discomfort", and "Anxiety / Depression," and all dimensions are described by 3 problem levels corresponding to patient response choices. A quality-of-life score is calculated based on the questionnaire responses.	From the enrolment to 3, 6, and 12 months post-discharge from the ICU
Analog Visual Scale	Use of an Analog Visual Scale to measure the quality of life	From the enrolment to 3, 6, and 12 months post-discharge from the ICU
Clinical Frailty Scale (CFS)	CFS is a clinical judgment-based frailty tool that scores from 1 (very fit) to 9 (terminally ill) by evaluating specific domains, including comorbidity, function, and cognition. CFS is recommended in Chile to assess frailty in older adults admitted to the ICU.	3, 6, and 12 months after the ICU discharge.
Pittsburgh Sleep Quality Index (PSQI).	The PSQI is a self-report questionnaire that assesses sleep quality in the past month. It comprises nineteen items that generate a score across seven components: subjective sleep quality, sleep latency, sleep duration, habitual sleep efficiency, sleep disturbances, sleep medication use, and daytime dysfunction. The sum of these seven components' scores yields the questionnaire's overall score.	3, 6, and 12 months after ICU discharge.
The fatigue assessment scale	It consists of ten items to determine physical and mental fatigue. Based on the questions, respondents can score from 1 to 5, where "one" corresponds to "never" and "five" to "always". The maximum number of points to be scored on this scale is 50; if the score is between 10-20, it corresponds to a standard score and no fatigue, while 21-50 equals substantial fatigue.	3, 6, and 12 months after ICU discharge.

Collaborators and Investigators

• Sponsor: Pontificia Universidad Catolica de Chile

Study record dates

Study Major Dates

• Study Start (Actual): September 15, 2025
• Primary Completion (Estimated): March 31, 2029
• Study Completion (Estimated): March 31, 2029

Study Registration Dates

• First Submitted: September 14, 2026
• First Submitted That Met QC Criteria: September 14, 2026
• First Posted (Actual): September 18, 2026

Study Record Updates

• Last Update Posted (Actual): September 18, 2026
• Last Update Submitted That Met QC Criteria: September 14, 2026
• Last Verified: September 1, 2026

More Information

Terms related to this study

• Keywords: Critical illness; Survivorship; Social determinants of health; Health equity; Health disparity; Post-Intensive Care syndrome; Intensive Care unit
• Additional Relevant MeSH Terms: Pathologic Processes; Disease Attributes; Pathological Conditions, Signs and Symptoms; Critical Illness; postintensive care syndrome
• Other Study ID Numbers: 230616016; 1241769 (Other Grant/Funding Number: Agencia Nacional de Investigación y Desarrollo, Fondecyt Regular,Chile)

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No