Post-traumatic sleep disturbance and psychological distress after chest trauma: A five-year observational study of incidence, predictors, recovery outcomes

Abstract

BACKGROUND

Chest trauma is an important clinical challenge, accounting for approximately 15% to 25% of all trauma-related hospitalizations. Immediate complications such as pneumothorax and hemothorax are well-documented, but long-term psychological sequelae, particularly sleep disturbances, remain inadequately characterized. Sleep disruption following trauma is both a hallmark and potential predictor of development of post-traumatic stress disorder. We hypothesized that sleep disturbance and psychological distress considerably impact recovery outcomes in patients with chest trauma.

AIM

To investigate the incidence, predictors, and impact of post-traumatic sleep disturbance and psychological distress on recovery outcomes in patients following chest trauma.

METHODS

This observational study involved 128 consecutive patients with chest trauma admitted to Tianjin Hospital, a tertiary referral trauma center in Tianjin, China, between January 2019 and December 2023. Sleep quality was assessed using the Pittsburgh Sleep Quality Index (PSQI), psychological distress was evaluated using the Hospital Anxiety and Depression Scale (HADS), and post-traumatic stress symptoms were measured using the Impact of Event Scale-Revised (IES-R). Assessments were conducted at admission, discharge, and 3, 6, and 12 months after injury. Multivariate logistic regression analysis was used to identify predictors of persistent sleep disturbance.

RESULTS

At discharge, 71.9% (92/128) of patients presented with sleep disturbance (PSQI > 5); at the 12-month follow-up visit, 34.4% (44/128) continued to experience clinically meaningful sleep problems. Patients with persistent sleep disturbance demonstrated higher HADS-Anxiety (9.82 ± 3.41 vs 5.63 ± 2.18, P < 0.001) and HADS-Depression (8.45 ± 2.97 vs 4.82 ± 2.05, P < 0.001) scores. Independent predictors of persistent sleep disturbance included an Injury Severity Score (ISS) of ≥ 16 [odds ratio (OR) = 3.24, 95% confidence interval (CI): 1.58–6.64], four or more rib fractures (OR = 2.87, 95%CI: 1.42-5.81), and baseline IES-R score of ≥ 24 (OR = 4.15, 95%CI: 1.96-8.79).

CONCLUSION

Sleep disturbance and psychological distress are highly prevalent following chest trauma and considerably impact recovery. An ISS of ≥ 16, four or more rib fractures, and baseline IES-R score of ≥ 24 were identified as independent predictors of persistent sleep disturbance. Early identification and intervention targeting patients at high risk may improve long-term outcomes.

Key Words: Chest trauma; Sleep disturbance; Psychological distress; Post-traumatic stress disorder; Pittsburgh Sleep Quality Index; Recovery outcomes; Rib fractures

Core Tip: This five-year observational study of 128 chest trauma patients reveals that sleep disturbance affects over 70% of patients at discharge, with one-third experiencing persistent problems at one year. We identified Injury Severity Score ≥ 16, multiple rib fractures, and elevated baseline post-traumatic stress symptoms as independent predictors of chronic sleep disturbance. The strong association between sleep problems and psychological distress suggests that integrated screening and early intervention protocols may significantly improve long-term recovery outcomes in this vulnerable population.

INTRODUCTION

Chest trauma represents a major cause of morbidity and mortality worldwide, accounting for approximately 10% to 15% of all trauma admissions and contributing to 20% to 25% of trauma-related deaths[1,2]. In addition to acute complications such as respiratory failure, pneumonia, and prolonged mechanical ventilation, chest trauma may also lead to substantial long-term physical and psychological burdens[3,4]. Although much research has focused on acute management and immediate outcomes, the characterization of the long-term psychological sequelae and their impact on functional recovery remains insufficient.

Sleep disturbance has emerged as a critical concern following traumatic injury. In addition to sleep problems, psychological distress-in the forms of anxiety, depression, and post-traumatic stress symptoms-is also commonly experienced after trauma, and may adversely affect recovery. Studies have demonstrated that up to 90% of individuals with post-traumatic stress disorder (PTSD) exhibit sleep problems, with such problems being considered a hallmark of trauma-related psychopathology[5,6]. The relationship between sleep disturbance and trauma is bidirectional: Acute sleep disruption impairs normal neurological and homeostatic processes, whereas chronic sleep problems contribute to the maintenance and exacerbation of PTSD symptoms[7,8]. Furthermore, inadequate sleep in the aftermath of trauma has been identified as a substantial risk factor for adverse psychological outcomes[9].

The unique characteristics of chest trauma present additional challenges to sleep quality. Rib fracture-related pain may persist beyond the acute phase and contribute to impaired physical recovery, while trauma-related sleep disturbance is closely associated with greater pain burden, worse mood, and poorer functional outcomes[10,11]. Studies have shown that the quality of life of patients with multiple rib fractures is much poorer than the population norms, with effects persisting for at least 2 years after injury[12,13]. The prevalences of chronic post-traumatic pain, anxiety, and depression in this population have been documented as exceeding 50%, highlighting the substantial psychological burden of thoracic injury[14].

Despite the recognized importance of the role that sleep has in trauma recovery, few studies have systematically examined sleep disturbance specifically in chest trauma populations. Therefore, the present study aimed to investigate the incidence and trajectory of post-traumatic sleep disturbance in patients with chest trauma, identify predictors of persistent sleep problems, and evaluate the association between sleep disturbance, psychological distress, and recovery outcomes over a 1-year follow-up period.

MATERIALS AND METHODS

Study design

This was a single-center, observational cohort study conducted at Tianjin Hospital, Tianjin, China. The study protocol was developed in accordance with the Strengthening the Reporting of Observational Studies in Epidemiology guidelines for cohort studies. This observational study was not registered in a public clinical trial registry because no assignment of interventions was involved. The research plan was reviewed and approved by the Medical Ethics Committee of Tianjin Hospital. The study was conducted in strict accordance with the ethical principles outlined in the Declaration of Helsinki and its subsequent amendments. All potential participants received detailed written and verbal information regarding the study objectives, procedures, potential risks and benefits, and their rights as research participants. Written informed consent was obtained from all participants prior to enrollment. Participants were informed of their right to withdraw from the study at any time without any impact on their clinical care. All data were collected, stored, and analyzed in compliance with applicable data protection regulations.

Sample size calculation

The sample size was estimated based on previous studies reporting the prevalence of persistent sleep disturbance following trauma. Assuming an expected prevalence of 35% for persistent sleep disturbance at 12 months, with a desired precision of ± 10% and a 95% confidence interval (CI), the minimum required sample size was calculated to be 88 patients. Accounting for an anticipated attrition rate of 20% during the 1-year follow-up period and the need for adequate power in the multivariate regression analyses (with approximately 8-10 candidate predictor variables), a target enrollment of 130 patients was determined. Sample size calculations were performed using G*Power software version 3.1.9.7 (Heinrich-Heine-Universität, Düsseldorf, Germany).

Study participants and eligibility criteria

Between January 1, 2019, and December 31, 2023, consecutive adult patients admitted to our institution with acute chest trauma were screened for eligibility. The inclusion criteria were: (1) Age ≥ 18 at the time of injury; (2) Acute blunt or penetrating chest trauma with documented thoracic injury confirmed using computed tomography (CT) imaging within 24 hours of admission; (3) A Glasgow Coma Scale score of ≥ 13 at the time of enrollment to ensure capacity for informed consent and reliable self-reporting; (4) Sufficient literacy and cognitive function to independently complete self-report questionnaires in Chinese; and (5) Willingness to provide informed consent and participate in scheduled follow-up assessments.

The exclusion criteria were: (1) Severe traumatic brain injury defined as an Abbreviated Injury Scale head region score of ≥ 3 or evidence of intracranial hemorrhage on CT imaging; (2) Spinal cord injury with neurological deficit; (3) Preexisting diagnosed sleep disorders including obstructive sleep apnea, insomnia disorder, narcolepsy, or restless legs syndrome documented in the medical records or self-reported by the patient; (4) Current or recent (within 6 months) treatment for psychiatric disorders including major depressive disorder, generalized anxiety disorder, PTSD, bipolar disorder, or schizophrenia; (5) Current use of psychotropic medications including antidepressants, anxiolytics, antipsychotics, or hypnotics; (6) Cognitive impairment or dementia that precluded providing informed consent; (7) Substance use disorder including alcohol dependence that was active; (8) An expected survival of < 6 months due to terminal illness or severe comorbidities; (9) Pregnancy; and (10) Inability to communicate in Chinese or complete the study questionnaires.

Data collection procedures

Data were collected by trained research coordinators who were not involved in the clinical care of the study participants. All coordinators underwent standardized training in the study procedures, administration of questionnaires, and protocols for data entry prior to initiation of the study. Baseline demographic data collected at admission included data on age, sex, body mass index, educational level, marital status, employment status, smoking history, alcohol consumption habits, and medical comorbidities present before injury assessed using the Charlson Comorbidity Index. Selected baseline variables relevant to the present analysis are presented in Table 1.

Table 1 Baseline demographic and clinical characteristics of the study participants (n = 128), n (%).

Variable	Value
Demographics
Age, year (mean ± SD)	48.7 ± 14.2
Male	98 (76.6)
BMI, kg/m2 (mean ± SD)	24.3 ± 3.6
Current smoker	46 (35.9)
CCI (median, IQR)	1 (0-2)
Mechanism of injury
Motor vehicle accident	80 (62.5)
Fall from height	28 (21.9)
Occupational injury	14 (10.9)
Other	6 (4.7)
Injury characteristics
ISS (median, IQR)	14 (9-21)
ISS ≥ 16	42 (32.8)
AIS thorax score (median, IQR)	3 (3-4)
Number of rib fractures (median, IQR)	4 (2-6)
Four or more rib fractures	52 (40.6)
Bilateral rib fractures	38 (29.7)
Flail chest	18 (14.1)
Associated thoracic injuries
Pneumothorax	75 (58.6)
Hemothorax	44 (34.4)
Pulmonary contusion	58 (45.3)
Sternal fracture	12 (9.4)
Treatment and hospital course
Tube drainage of the chest	68 (53.1)
Surgical rib fixation	22 (17.2)
ICU admission	41 (32.0)
ICU LOS, days (median, IQR)	5 (3-9)
Hospital LOS, days (mean ± SD)	14.8 ± 8.6

BMI: Body mass index; CCI: Charlson Comorbidity Index; ISS: Injury Severity Score; IQR: Interquartile range; AIS: Abbreviated Injury Scale; ICU: Intensive care unit; LOS: Length of stay.

The clinical and injury-related variables recorded included mechanism of injury, categorized as motor vehicle accident, fall from height, occupational injury, and other causes; Injury Severity Score (ISS), calculated using the Abbreviated Injury Scale 2005 Update; Abbreviated Injury Scale thorax score; thoracic trauma severity score; number and anatomical location of rib fractures (unilateral vs bilateral, upper vs lower ribs), presence of flail chest, defined as the fracture of three or more consecutive ribs in two or more places resulting in paradoxical chest wall movement; and associated thoracic injuries including pneumothorax, hemothorax, pulmonary contusion, sternal fracture, and clavicle fracture. The treatment-related variables recorded included the need for tube drainage of the chest, surgical intervention (rib fixation, video-assisted thoracoscopic surgery, thoracotomy), admission to the intensive care unit, duration of mechanical ventilation, use of regional analgesia (epidural or paravertebral block), and length of hospital stay.

Assessment instruments

Pittsburgh Sleep Quality Index: Sleep quality was assessed using the validated Chinese version of the Pittsburgh Sleep Quality Index (PSQI)[15,16]. The PSQI is a 19-item self-report questionnaire that is used to evaluate subjective sleep quality over the preceding 1-month period. The instrument comprises seven component scores: (1) Subjective sleep quality; (2) Sleep latency (time to fall asleep); (3) Sleep duration; (4) Habitual sleep efficiency (ratio of time asleep to time in bed); (5) Sleep disturbances (frequency of specific sleep-disrupting events); (6) Use of sleep medication; and (7) Daytime dysfunction (difficulty staying awake and maintaining enthusiasm). Each component is scored from 0 to 3, yielding a global score ranging from 0 to 21; higher scores indicate poorer sleep quality. A global PSQI score of > 5 has been established as the threshold for clinically meaningful sleep disturbance, demonstrating a sensitivity of 89.6% and specificity of 86.5% for distinguishing good from poor sleepers. The Chinese version of the PSQI has demonstrated excellent psychometric properties, yielding a Cronbach’s alpha of 0.84 and test–retest reliability of 0.85.

Hospital Anxiety and Depression Scale: Psychological distress was evaluated using the validated Chinese version of the Hospital Anxiety and Depression Scale (HADS)[17,18]. The HADS is a 14-item self-report instrument specifically designed for use in medical populations, with items selected to minimize contamination by somatic symptoms of physical illness. The scale comprises two subscales: The HADS-Anxiety (HADS-A, 7 items) and HADS-Depression (HADS-D, 7 items). Each item is scored from 0 to 3, providing subscale scores ranging from 0 to 21. Established cutoff scores categorize symptom severity as 0-7 (normal), 8-10 (mild), 11-14 (moderate), and 15-21 (severe). A score of ≥ 8 on either subscale indicates probable caseness for anxiety or depression, respectively. The HADS has demonstrated robust psychometric properties in trauma populations, with both subscales yielding Cronbach’s alpha values of 0.83 to 0.85[19].

Impact of Event Scale-Revised: Post-traumatic stress symptoms were assessed using the validated Chinese version of the Impact of Event Scale-Revised (IES-R)[20,21]. The IES-R is a 22-item self-report measure used to evaluate used to evaluate subjective distress caused by a specific traumatic event that took place in the preceding 7 days. Items are rated on a 5-point Likert scale ranging from 0 (not at all) to 4 (extremely). The instrument comprises three subscales that correspond to the core symptom clusters of PTSD: Intrusion (8 items), avoidance (8 items), and hyperarousal (6 items). Total scores range from 0 point to 88 points, with higher scores indicating a greater severity of the symptoms of post-traumatic stress. A total score of ≥ 24 points is considered indicative of clinically meaningful post-traumatic stress, whereas a score of ≥ 33 points is considered to suggest probable PTSD that warrants clinical evaluation[22]. The IES-R has demonstrated excellent internal consistency (Cronbach’s alpha, 0.92-0.96) and has been validated in survivors of motor vehicle accidents and other trauma populations[23].

Pain assessment: Pain intensity was evaluated using the Numeric Rating Scale, an 11-point scale ranging from 0 points (no pain) to 10 points (worst pain imaginable). Participants were asked to rate their average pain intensity over the past 24 hours at each assessment time point. A score of ≥ 4 points was considered indicative of moderate to severe pain that required intervention.

Functional outcome assessment: Functional outcomes were assessed at the 12-month follow-up visit. These outcomes included return to work status (returned to pre-injury occupation, returned to modified duties, not returned, not applicable), return to pre-injury activity level, and presence of chronic pain (defined as pain persisting for > 3 months after injury). Return-to-work status was used as a pragmatic indicator of functional recovery and was interpreted together with other clinical outcomes.

Follow-up procedures and timeline

All questionnaires (PSQI, HADS, IES-R, and Numeric Rating Scale) were administered at the five pre-specified time points of: (1) Baseline, namely, assessment within 48 hours to 72 hours of hospital admission, after initial stabilization and when patients were able to participate; (2) Hospital discharge (typically 7-21 days after admission); (3) 3 months (± 2 weeks) after injury; (4) 6 months (± 2 weeks) after injury; and (5) 12 months (± 2 weeks) after injury. Baseline and discharge assessments were conducted in person during hospitalization. Follow-up assessments at 3, 6, and 12 months after injury were conducted, when possible, during scheduled outpatient clinic visits. For participants unable to attend clinic appointments, questionnaires were administered via structured telephone interviews by trained research coordinators using a standardized script. To maximize retention, participants received reminder calls or text messages 1 week and 24 hours prior to each scheduled follow-up visit. Participants who missed scheduled assessments were contacted within 1 week to reschedule.

Quality control measures

Several quality control measures were implemented to ensure data integrity. All completed questionnaires were reviewed for completeness and logical consistency by research coordinators before data entry. Double data entry was performed independently by two research assistants, with discrepancies resolved by referencing the source documents. Range checks and logical validation rules were applied to all variables. Missing data patterns were monitored throughout the study period, and the reasons for assessments being missed were documented.

Statistical analysis

All statistical analyses were performed using IBM SPSS Statistics for Windows version 26.0 (IBM Corp., Armonk, NY, United States) and R version 4.2.1 (R Foundation for Statistical Computing, Vienna, Austria). Continuous variables were first assessed for normality using the Shapiro-Wilk test and visual inspection of histograms and Q-Q plots. Normally distributed continuous variables are expressed as mean ± SD, whereas non-normally distributed variables are expressed as median with interquartile range (IQR). Categorical variables are expressed as n (%).

Comparisons between groups (patients with vs those without persistent sleep disturbance at 12 months) were performed using independent samples t-tests for normally distributed continuous variables, Mann-Whitney U tests for non-normally distributed continuous variables, and χ² or Fisher’s exact tests for categorical variables, as appropriate. Changes in sleep and psychological measures over time were evaluated using repeated measures analysis of variance with the Greenhouse-Geisser correction applied for violations of sphericity. Post-hoc pairwise comparisons were performed using Bonferroni adjustment for multiple testing.

Univariate logistic regression analysis was initially performed to identify candidate predictors of persistent sleep disturbance (defined as a PSQI of > 5 at 12 months). Variables with a P < 0.10 in the univariate analysis were entered into a multivariate logistic regression model using backward stepwise selection. Model fit was assessed using the Hosmer-Lemeshow goodness-of-fit test, and discriminative ability was evaluated using the area under the receiver operating characteristic curve. The results are presented as odds ratios (OR) with 95%CI. Correlations between continuous variables were assessed using Pearson correlation coefficients (r) for normally distributed data or Spearman rank correlation coefficients (ρ) for non-normally distributed data. A two-tailed P value of < 0.05 was considered statistically significant for all analyses.

RESULTS

Patient enrollment and baseline characteristics

During the 5-year study period, a total of 486 patients with chest trauma were admitted to our institution. Of these, 312 patients were screened for eligibility, with 156 meeting the preliminary inclusion criteria. Twenty-eight patients were subsequently excluded: Twelve had preexisting sleep disorders that were identified during detailed history taking, eight were currently undergoing psychiatric treatment, five had cognitive impairment, and three declined participation. Thus, 128 patients (82.1% of those meeting the preliminary criteria) were enrolled and completed the baseline assessments. The completion rates for follow-up were 96.9% (124/128) at discharge, 95.3% (122/128) at 3 months, 93.8% (120/128) at 6 months, and 95.3% (122/128) at 12 months. Six patients were lost to follow-up: Four relocated and two withdrew their consent. No deaths occurred during the study period.

The baseline demographic and clinical characteristics of the study cohort are presented in Table 1. The cohort predominantly comprised males (76.6%), and the mean age of the cohort was 48.7 ± 14.2 years. Motor vehicle accidents were the most common mechanism of injury (62.5%), followed by falls from height (21.9%). The median ISS was 14 (IQR: 9-21), with 32.8% of patients sustaining severe trauma (ISS ≥ 16). The median number of rib fractures was four (IQR: 2-6), with 40.6% of patients having four or more rib fractures. Of the participants, 14.1% had flail chest. The most common associated thoracic injuries were pneumothorax (58.6%), pulmonary contusion (45.3%), and hemothorax (34.4%).

Incidence and trajectory of sleep disturbance and psychological distress

The temporal patterns of sleep disturbance and psychological symptoms are presented in Table 2. Most patients (89.1%) presented with clinically meaningful sleep disturbance at baseline, reflecting the acute impact of trauma and hospitalization on sleep. The prevalence decreased progressively through follow-up but remained substantial, with 34.4% of patients continuing to experience sleep disturbance at 12 months. The mean global PSQI scores demonstrated substantial improvement over time (P < 0.001 for trend). Similarly, anxiety, depression, and post-traumatic stress symptoms showed meaningful reductions across all time points, although a substantial minority of patients continued to meet the thresholds for probable caseness at 1 year.

Table 2 Trajectory of sleep quality and psychological measures over 12 months of follow-up, n (%)/mean ± SD.

Variable	Baseline	Discharge	3 months	6 months	12 months	P value
PSQI global score	12.84 ± 3.72	9.67 ± 3.45	7.23 ± 3.18	6.14 ± 2.89	5.47 ± 2.65	< 0.001
PSQI > 5	114 (89.1)	92 (71.9)	70 (54.7)	54 (42.2)	44 (34.4)	< 0.001
HADS-A score	10.24 ± 3.86	8.56 ± 3.42	7.12 ± 3.15	6.34 ± 2.87	6.08 ± 2.74	< 0.001
HADS-A ≥ 8	86 (67.2)	72 (56.3)	52 (40.6)	42 (32.8)	37 (28.9)	< 0.001
HADS-D score	8.42 ± 3.54	7.18 ± 3.12	5.86 ± 2.78	5.24 ± 2.56	5.12 ± 2.48	< 0.001
HADS-D ≥ 8	68 (53.1)	56 (43.8)	38 (29.7)	32 (25.0)	29 (22.7)	< 0.001
IES-R total score	38.6 ± 14.2	32.4 ± 12.8	26.8 ± 11.4	23.2 ± 10.6	21.4 ± 10.2	< 0.001
IES-R ≥ 24	96 (75.0)	82 (64.1)	58 (45.3)	46 (35.9)	39 (30.5)	< 0.001
IES-R ≥ 33	72 (56.3)	51 (39.8)	34 (26.6)	26 (20.3)	23 (18.0)	< 0.001
Pain NRS score	6.8 ± 1.9	4.2 ± 1.6	2.8 ± 1.4	2.1 ± 1.2	1.6 ± 1.1	< 0.001

P values were derived from repeated measures analysis of variance or Cochran’s Q test. PSQI: Pittsburgh Sleep Quality Index; HADS-A: Hospital Anxiety and Depression Scale-Anxiety subscale; HADS-D: Hospital Anxiety and Depression Scale-Depression subscale; IES-R: Impact of Event Scale-Revised; NRS: Numeric Rating Scale.

Comparison between patients with and without persistent sleep disturbance

Patients were stratified based on the presence (n = 44, 34.4%) or absence (n = 84, 65.6%) of persistent sleep disturbance at the 12-month follow-up visit. As shown in Table 3, patients with persistent sleep disturbance were much older and had a greater severity of injury, more rib fractures, longer hospital stays, and greater baseline psychological distress. At the 12-month follow-up visit, these patients demonstrated substantially worse scores across all psychological measures and poorer functional outcomes.

Table 3 Comparison between patients with and without persistent sleep disturbance at the 12-month follow-up visit, n (%)/mean ± SD.

Variable	Persistent sleep disturbance (n = 44)	No persistent sleep disturbance (n = 84)	P value
Demographics
Age, years	53.2 ± 13.8	46.4 ± 14.0	0.012
Male	32 (72.7)	66 (78.6)	0.459
Injury characteristics
ISS	18.7 ± 7.2	12.4 ± 5.8	< 0.001
ISS ≥ 16	24 (54.5)	18 (21.4)	< 0.001
Number of rib fractures	5.8 ± 2.4	3.6 ± 1.9	< 0.001
Four or more rib fractures	28 (63.6)	24 (28.6)	< 0.001
Flail chest	10 (22.7)	8 (9.5)	0.037
Hospital course
ICU admission	22 (50.0)	19 (22.6)	0.002
Hospital LOS, days	18.9 ± 9.4	12.6 ± 7.2	< 0.001
Baseline psychological measures
PSQI score	14.6 ± 3.2	11.9 ± 3.6	< 0.001
IES-R score	46.8 ± 12.4	34.2 ± 13.6	< 0.001
IES-R ≥ 24	42 (95.5)	54 (64.3)	< 0.001
12-month outcomes
PSQI score	8.42 ± 2.14	3.94 ± 1.86	< 0.001
HADS-A score	9.82 ± 3.41	5.63 ± 2.18	< 0.001
HADS-D score	8.45 ± 2.97	4.82 ± 2.05	< 0.001
IES-R total score	34.6 ± 12.8	18.4 ± 9.6	< 0.001
Return to work	26 (59.1)	72 (85.7)	< 0.001
Chronic pain	32 (72.7)	26 (31.0)	< 0.001

ISS: Injury Severity Score; ICU: Intensive care unit; LOS: Length of stay; PSQI: Pittsburgh Sleep Quality Index; IES-R: Impact of Event Scale-Revised; HADS-A: Hospital Anxiety and Depression Scale-Anxiety subscale; HADS-D: Hospital Anxiety and Depression Scale-Depression subscale.

Predictors of persistent sleep disturbance

Univariate and multivariate logistic regression analyses were performed to identify predictors of persistent sleep disturbance at 12 months (Table 4). In the final multivariate model, three variables remained independently associated with persistent sleep disturbance: ISS ≥ 16 (OR = 3.24, 95%CI: 1.58-6.64, P = 0.001), four or more rib fractures (OR = 2.87, 95%CI: 1.42-5.81, P = 0.003), and a baseline IES-R score of ≥ 24 points (OR = 4.15, 95%CI: 1.96-8.79, P < 0.001). The model demonstrated good discrimination, yielding an area under the receiver operating characteristic curve of 0.82 (95%CI: 0.74-0.89) and adequate calibration (Hosmer-Lemeshow P = 0.64).

Table 4 Univariate and multivariate logistic regression analysis of predictors for persistent sleep disturbance at 12 months after injury.

Variable	Univariate OR (95%CI)	P value	Multivariate OR (95%CI)	P value
Age ≥ 50 years	2.18 (1.12-4.24)	0.022	1.68 (0.78-3.62)	0.186
Male sex	0.73 (0.32-1.67)	0.459	-	-
ISS ≥ 16	4.42 (2.18-8.96)	< 0.001	3.24 (1.58-6.64)	0.001
Rib fractures ≥ 4	4.38 (2.12-9.04)	< 0.001	2.87 (1.42-5.81)	0.003
Flail chest	2.79 (1.04-7.52)	0.042	1.42 (0.48-4.21)	0.528
Pneumothorax	1.86 (0.92-3.76)	0.084	1.24 (0.56-2.75)	0.596
Pulmonary contusion	2.14 (1.08-4.24)	0.029	1.38 (0.64-2.98)	0.412
ICU admission	3.42 (1.68-6.96)	0.001	1.56 (0.68-3.58)	0.294
Baseline IES-R ≥ 24	11.67 (3.38-40.26)	< 0.001	4.15 (1.96-8.79)	< 0.001
Baseline PSQI > 10	3.86 (1.84-8.10)	< 0.001	1.72 (0.74-4.00)	0.208

Variables with P < 0.10 in univariate analysis were entered into the multivariate model. Model performance: Area under the receiver operating characteristic curve = 0.82 (95% confidence interval: 0.74-0.89); Hosmer-Lemeshow P = 0.64. OR: Odds ratio; CI: Confidence interval; ISS: Injury Severity Score; ICU: Intensive care unit; IES-R: Impact of Event Scale-Revised; PSQI: Pittsburgh Sleep Quality Index.

Correlations between sleep quality, psychological distress, and recovery outcomes

Table 5 presents the correlation matrix between sleep quality and psychological measures at the 12-month follow-up visit. Strong positive correlations were observed between the PSQI global scores and all psychological distress measures, including the HADS-A (r = 0.62), HADS-D (r = 0.58), and IES-R total (r = 0.67) scores. Among the IES-R subscales, symptoms of hyperarousal showed the strongest correlation with sleep quality (r = 0.71), followed by symptoms of intrusion (r = 0.64) and avoidance (r = 0.52). Pain intensity also demonstrated moderate correlation with sleep quality (r = 0.48; all P < 0.001).

Table 5 Correlation matrix between sleep quality and psychological measures at the 12-month follow-up visit.

	PSQI	HADS-A	HADS-D	IES-R	Intrusion	Avoidance	Hyperarousal
PSQI	1.00
HADS-A	0.62a	1.00
HADS-D	0.58a	0.68a	1.00
IES-R total	0.67a	0.72a	0.64a	1.00
Intrusion	0.64a	0.68a	0.56a	0.92a	1.00
Avoidance	0.52a	0.58a	0.54a	0.86a	0.72a	1.00
Hyperarousal	0.71a	0.74a	0.62a	0.88a	0.78a	0.68a	1.00
Pain NRS	0.48a	0.42a	0.38a	0.44a	0.42a	0.36a	0.46a

^aP < 0.001.

PSQI: Pittsburgh Sleep Quality Index; HADS-A: Hospital Anxiety and Depression Scale-Anxiety subscale; HADS-D: Hospital Anxiety and Depression Scale-Depression subscale; IES-R: Impact of Event Scale-Revised; NRS: Numeric Rating Scale.

DISCUSSION

Through this prospective observational study, we provide evidence regarding the incidence, predictors, and impact of sleep disturbance and psychological distress in patients after they have experienced chest trauma. Our findings revealed that sleep disturbance was highly prevalent in this population, affecting over 70% of patients at discharge and persisting in approximately one-third at the 1-year follow-up visit. Furthermore, we identified severity of injury, number of rib fractures, and baseline post-traumatic stress symptoms as independent predictors of persistent sleep problems, while demonstrating strong associations between sleep disturbance, psychological distress, and adverse recovery outcomes.

The high prevalence of sleep disturbance that we observed in our cohort is consistent with that reported in the broader trauma literature. Studies have demonstrated that up to 90% of individuals with PTSD have sleep problems, with sleep problems considered a hallmark of trauma-related psychopathology[5,6]. Notably, the persistence of sleep disturbance at 1 year that we observed in 34.4% of our patients exceeded the rates previously observed in general trauma populations, likely reflecting the unique challenges posed by chest trauma; these challenges include chronic pain, respiratory symptoms, and positional discomfort[12-14]. Our findings align with those of previous studies, demonstrating that patients with multiple rib fractures experience a considerably reduced quality of life that fails to return to the levels of the population norms for at least 2 years after injury[13].

Identifying the severity of injury, number of rib fractures, and baseline post-traumatic stress symptoms as predictors of persistent sleep disturbance has important clinical implications. These findings suggest that early identification and targeted intervention are warranted in patients presenting with more severe injuries and acute psychological distress. The association between the baseline IES-R scores and subsequent sleep problems confirms the bidirectional relationship between sleep disturbance and PTSD, whereby acute sleep disruption may contribute to the development of PTSD while post-traumatic stress symptoms perpetuate sleep difficulties[7,8]. This relationship highlights sleep disturbance as both a marker of the severity of trauma and a potential therapeutic target for improving psychological outcomes.

The results of the correlation analysis revealed that, of the IES-R subscales, symptoms of hyperarousal were most strongly associated with sleep quality. This finding is consistent with theoretical models proposing that hyperarousal is a core mechanism underlying both PTSD and sleep disturbance[7,24]. The heightened vigilance and physiological activation characteristic of hyperarousal directly interfere with the normal initiation and maintenance of sleep, creating a vicious cycle that perpetuates both sleep problems and trauma-related symptoms.

Several limitations of this study must be considered. First, the single-center design may have limited the generalizability of our findings to other populations and healthcare settings. Second, the reliance on self-report measures introduced potential recall and reporting biases, even though all the instruments we used have demonstrated validity in trauma populations[15-23]. Third, the absence of objective sleep measurements, such as those obtained using polysomnography or actigraphy, precluded assessment of the specific abnormalities of the sleep architecture. Fourth, we did not systematically evaluate pre-injury sleep quality or psychiatric history, which may have influenced the post-traumatic outcomes. Fifth, potential confounding variables such as the use of analgesic medication and social support were not comprehensively assessed. Sixth, the observational design prevented causal inferences regarding the relationship between sleep disturbance and recovery outcomes from being made. Finally, return-to-work status is a pragmatic functional outcome that may be influenced by social, occupational, and economic factors beyond clinical recovery alone.

Despite these limitations, our findings provide clinically relevant insights for the management of patients with chest trauma. The high prevalence and persistence of sleep disturbance observed in our cohort, together with its strong association with psychological distress and functional impairment, underscore the clinical importance of incorporating sleep-focused assessment into post-trauma care. These findings further suggest that early identification and treatment of sleep disturbance may be particularly beneficial in patients with marked psychological distress after trauma[25,26]. Future studies should evaluate whether targeted sleep interventions, such as cognitive behavioral therapy for insomnia, can improve both sleep quality and broader psychological outcomes in this population[27-30].

CONCLUSION

Sleep disturbance and psychological distress were highly prevalent after chest trauma, and they demonstrated meaningful associations with adverse recovery outcomes, including chronic pain and reduced return-to-work rates. An ISS of ≥ 16, four or more rib fractures, and baseline post-traumatic stress symptoms (IES-R ≥ 24 points) independently predicted persistent sleep problems at 1 year. These findings support the need to implement systematic screening for sleep disturbance and psychological distress in patients with chest trauma, thus enabling long-term recovery outcomes to be optimized through early intervention that targets individuals at high risk.