Everyday life experiences for evaluating post-traumatic stress disorder symptoms

ABSTRACT

Background: Previous research has highlighted the importance of regularizing daily routines for maintaining mental health. Little is known about whether and how regularity of daily routines is associated with reduced post-traumatic stress disorder (PTSD) symptoms.

Objective: We aimed to examine the associations between regularity of daily routines and PTSD symptoms in two studies (N = 796).

Method: In Study 1, prospective data were analysed with the latent change score model to investigate the association between sustainment of regular daily routines and change in PTSD symptoms over time amid massive civil unrest in Hong Kong in 2019. Study 2 used vignette as a quasi-experimental method to assess the ability of maintaining regular daily routines in face of a major stressor, and tested its associations with PTSD symptoms.

Results: In Study 1, increased regularity of diverse daily routines was inversely associated with increased PTSD symptoms amid the civil unrest in Hong Kong (β = −.427 to −.224, 95% confidence intervals [−.543 to −.359, −.310 to −.090], p values < .01). In Study 2, a greater ability to maintain regular daily routines during stress was associated with lower levels of PTSD symptoms (β = −.285 to −.096, 95% confidence intervals [−.379 to −.189, −.190 to −.003], p values < .05).

Conclusions: Our findings suggest the benefit of considering diverse everyday activities in evaluating PTSD symptoms in both clinical and subclinical populations. Interventions with the direct focus on the role of daily living could promote psychological resilience during and after potentially traumatic events.

HIGHLIGHTS

• Increased regularity of routines (hygiene, healthy eating, sleep, duties at home, exercising, leisure and social activities, work/study involvement) was related to less increase in PTSD symptoms amid widespread civil unrest.

• The ability to maintain regular routines during stress was inversely associated with PTSD symptoms.

• Research and interventions with the direct focus on the role of daily living could promote psychological resilience during and after potentially traumatic events.

Antecedentes: Las investigaciones anteriores han destacado la importancia de regularizar las rutinas diarias para mantener la salud mental. Se sabe poco acerca de si la regularidad de las rutinas diarias se asocia con la reducción de los síntomas del TEPT y de qué manera.

Objetivo: Nuestro objetivo fue examinar las asociaciones entre la regularidad de las rutinas diarias y los síntomas del TEPT en dos estudios (N=796).

Método: En el Estudio 1, se analizaron datos prospectivos con el modelo de puntaje de cambio latente para investigar la asociación entre la sostenibilidad de las rutinas diarias regulares y el cambio en los síntomas del TEPT a lo largo del tiempo en medio de los disturbios civiles masivos en Hong Kong en el 2019. El Estudio 2 usó una viñeta como método cuasi-experimental para evaluar la capacidad de mantener las rutinas diarias regulares frente a un factor estresante importante y probar sus asociaciones con los síntomas del TEPT.

Resultados: En el Estudio 1, el aumento de la regularidad de diversas rutinas diarias se asoció inversamente con un aumento de los síntomas de TEPT en medio de los disturbios civiles en Hong Kong (β=−.427 a −.224, IC del 95% [−.543 a −.359, − .310 a −.090], ps<.01). En el Estudio 2, una mayor capacidad para mantener rutinas diarias regulares durante el estrés se asoció con niveles más bajos de síntomas del TEPT (β= −.285 a −.096, IC del 95% [−.379 a −.189, −.190 a −.003], ps<.05).

Conclusiones: Nuestros hallazgos sugieren el beneficio de considerar diversas actividades cotidianas al evaluar los síntomas del TEPT en poblaciones clínicas y subclínicas. Las intervenciones con un enfoque directo hacia el papel de la vida diaria podrían promover la resiliencia psicológica durante y después de eventos potencialmente traumáticos.

背景：先前的研究强调了规律化日常生活对于保持心理健康的重要性。然而，关于日常生活的规律性是否以及如何与减轻创伤后应激障碍 (PTSD) 症状相关，我们知之甚少。

目标：我们旨在通过两项研究 (N = 796) 检验日常生活规律与 PTSD 症状之间的关联。

方法：研究 1 使用潜变化分数模型分析了一项前瞻性数据，以调查在 2019 年香港社会风波期⁣⁣间维持规律的日常生活与 PTSD 症状随时间变化之间的关系。研究 2 使用小片段作为准实验方法来评估在面对主要压力源时保持规律的日常生活的能力，并测试其与 PTSD 症状的关联。

结果：在研究 1 中，多样化日常生活的规律性增加与 PTSD 症状的增加呈负相关 (β = −.427 to −.224, 95% CIs [−.543 to −.359, −.310 to −.090], ps < .01)。研究 2 发现在面对压力时维持规律的日常生活的能力与 PTSD 症状之间呈负相关 (β = −.285 to −.096, 95% CIs [−.379 to −.189, −.190 to −.003], ps < .05)。

结论：我们的研究结果表明，在评估临床和亚临床人群的 PTSD 症状时，考虑多样化的日常活动是有益的。直接关注日常生活作用的干预措施可以促进潜在创伤事件期间和之后的心理韧性。

KEYWORDS:

• PTSD symptoms
• trauma exposure
• daily routines
• regularity
• context sensitivity and responsiveness to feedback

PALABRAS CLAVE:

• Síntomas del TEPT
• exposición al trauma
• rutinas diarias
• regularidad
• sensibilidad al contexto y capacidad de respuesta a la retroalimentación

关键词:

• PTSD 症状
• 创伤暴露
• 日常生活
• 规律性
• 情境敏感性和反馈反应

1. Introduction

Trauma exposure is common. In the World Health Organization (WHO) World Mental Health Survey among 68,894 adults from 24 countries across six continents, 70.4% respondents reported that they had experienced at least one traumatic event among 29 types, such as war, physical violence, and accidents (Kessler et al., 2017). People with higher levels of trauma exposure could present an increased risk of developing clinically significant post-traumatic stress disorder (PTSD) symptoms (Lowe et al., 2014; Ozer et al., 2003). Psychotherapies with the purpose of ameliorating trauma memory or related thoughts have demonstrated clinically important effects on the patients (Bisson et al., 2007; Lewis et al., 2020). Many patients, nonetheless, may not be willing to engage in trauma-focused psychotherapies, possibly because of an intolerance of the traumatic images in the treatments (Lewis et al., 2020; Shea et al., 2020). In addition, as many as 30% of patients with PTSD may show negligible improvement in PTSD symptoms after psychotherapies (Bradley et al., 2005; Schwartze et al., 2019), among which a majority may prefer not to access specialized mental health treatments (Bryant, 2019; Koenen et al., 2017). Therefore, identifying alternative factors that could alleviate PTSD symptoms could help to overcome these challenges and lead to better management of people suffering from PTSD symptoms (Bryant, 2019).

Recent studies have suggested the importance of considering daily routines, since the ongoing adversities of trauma exposure usually restrict individuals from engaging in important daily activities (Hobfoll et al., 2012; Parks et al., 2018). There is evidence showing that higher daily routine disruptions prospectively predicted poorer cognitive adaptation such as self-efficacy and meaning-making (Tao, Li et al., 2023) and higher levels of PTSD symptoms (Tao, Yung et al., 2023) amid COVID-19. The restoration of pre-earthquake daily life 1.5 years after the Great East Japan Earthquake was associated with lower levels of psychological distress 6 years after the earthquake (Goodwin et al., 2020). In a sample of 1336 Israeli secondary school students, those who could maintain more daily routines, especially leisure activities, amid the ongoing terrorism reported lower levels of PTSD symptoms and lower functional impairment (Pat-Horenczyk, 2005). Among people with PTSD, major depressive disorder, and sleep disturbance receiving Cognitive Behavioral Social Rhythm Therapy (CBSRT), an increase in lifestyle regularity, as measured by the Social Rhythm Metric (SRM) (Monk et al., 1991), was associated with decreased PTSD symptoms following the treatment (Haynes et al., 2016). More research is needed to investigate whether and how changes in different daily routines are distinctly associated with changes in PTSD symptoms.

The importance of the regularity of daily routines in assessments and interventions of psychopathology has been highlighted by the Social Zeitgeber Theory, which proposes that people tend to perform everyday activities regularly to keep inherent biological rhythms (e.g. body temperature, melatonin, and cortisol rhythms) synchronized with the 24 h cycle (Ehlers et al., 1988; Grandin et al., 2006). Irregular daily routines resulting from stressful life events are hypothesized to disrupt circadian rhythms, which, in turn, evoke somatic symptoms that are directly related to higher risks of developing affective episodes (Ehlers et al., 1988; Grandin et al., 2006). Consistent with the Social Zeitgeber Theory, less regular daily activities at baseline predicted greater odds of first onset of bipolar spectrum disorder in 32 months among at-risk adolescents who exhibited reward hypersensitivity (Alloy et al., 2015). A lower frequency of daily activities performed regularly predicted higher levels of depressive symptoms in 4 month follow-up in a sample of university students with bipolar II or cyclothymia (Sylvia et al., 2009). There is also a growing body of empirical evidence on the effectiveness of Interpersonal and Social Rhythm Therapy in treating bipolar spectrum disorders, with the goal of regularizing sufficient adaptive daily routines to stabilize mood (Inder et al., 2015; Swartz et al., 2012).

The Drive to Thrive (DTT) theory (Hou et al., 2018) further extended prior work by emphasizing that stress resilience is manifested in the sustainment of daily routines during trauma or chronic stress conditions. DTT theory defined essential behaviours for maintaining livelihood and biological needs, including personal hygiene, sleep, healthy eating, and home duties as primary routines, whereas optional behaviours performed based on motivation and preferences, including exercising, leisure, social activities, and work/study involvement, were defined as secondary routines. The sustainment of daily routines refers to both the maintenance and enhancement of the regularity of daily routines over time, which is conceptualized against persistent and emerging daily routine disruptions (Li et al., 2022; Liang et al., 2023). Fewer disruptions to regular healthy eating, sleep, socializing, and leisure activities were consistently associated with lower odds of probable anxiety and depression during mass trauma, including civil unrest (Hou, Hall et al., 2021) and the COVID-19 pandemic (Hou, Lee et al., 2021). Disruptions to regular routines also mediated the association between low socioeconomic status and probable depression (Tao, Lee et al., 2022), such that lower socioeconomic resources predicted more disrupted daily routines, which, in turn, related to higher odds of probable depression, especially those with higher trauma exposure during the unrest (Lai et al., 2020; Tao, Li et al., 2022). People with multimorbidity who did not experience significant changes in exercising, socializing, and the use of organizational services following the outbreak of COVID-19 showed better mental health compared to those who experienced significant changes in these activities (Lau et al., 2021).

According to the DTT theory, resilience to traumatic and chronic stress can be achieved by constructing a sustainable everyday life structure (Hou et al., 2018). Longitudinal evidence showed that the levels of depressive and anxiety symptoms of individuals who could enhance regular routines over time were comparable to the symptom levels of individuals who did not experience disrupted daily life under the COVID-19 pandemic (Liang et al., 2023). A regular structure of daily life could be proactively sustained by three behavioural pathways: consolidating disrupted routines, replacing terminated routines, and supplementing adaptive new routines (Hou et al., 2020; Hou, Liang et al., 2021). In immediate deprived conditions, such as mass conflicts and natural disasters, the disruption or termination of primary routines could cause a rapid breakdown of overall daily living, while the disruption or termination of secondary routines could reduce overall resourcefulness, leading to a gradual breakdown of daily living (Doğan & Kahraman, 2011; Hou et al., 2018; Tatsuki, 2007). Resources are needed to consolidate, replace, and add routines, but the quantity of resources invested in each routine is disproportionate (Baltes et al., 1999; Baltes & Lang, 1997; Hobfoll, 1998). The consolidation of disrupted routines requires fewer resources compared to the replacement of terminated routines, as the latter involves building new routines from scratch. Therefore, the adaptive priority of (1) primary over secondary routines and (2) disruption over termination could be considered to guide the sustainment of daily routines (Hou et al., 2018; Hou et al., 2020).

This adaptive priority may serve as the cornerstone of the ability to regularize disrupted/terminated daily routines, which has been conceptualized as two sequential components of regulatory flexibility; namely, context sensitivity and responsiveness to feedback (Bonanno & Burton, 2013). Previous studies have observed the positive associations between emotion context insensitivity and several affective disorders, such as anxiety and depression (Coifman & Bonanno, 2010; Rottenberg et al., 2005). Individuals with low levels of either context sensitivity or responsiveness to feedback have exhibited higher levels of depressive and anxiety symptoms than those with high levels of both of these components (Chen & Bonanno, 2021). Emotion context sensitivity has also been shown to benefit adjustment to severe stressful life events, such as the loss of significant others (Coifman & Bonanno, 2010), chronic illness (Harvey et al., 2016), and affective disorders (Bylsma et al., 2008; Rottenberg et al., 2005).

Context sensitivity in sustaining regular routines refers to the degree to which individuals are able to accurately detect different changes to regular routines and adopt the most effective strategies to restore their regularity. Responsiveness to feedback indicates the extent to which individuals can evaluate the effectiveness of the selected strategies in accordance with the routine changes, discontinue ineffective strategies, and re-engage in alternative, effective strategies. A 2021 study revealed that context sensitivity and responsiveness to feedback in sustaining daily routines were associated with lower psychological distress, and the association was stronger among individuals at medium/high levels of perceived financial difficulty relative to those with low levels (Hou, Liang et al., 2021). Currently, there is a deficit of knowledge about the extent to which regularizing daily routines is associated with reduced PTSD symptoms.

The present study aims to investigate the nature of associations between sustainment of regular daily routines and PTSD symptoms, in two studies. In Study 1 (n = 287), prospective analyses were conducted to investigate whether change in the regularity of daily routines was associated with change in PTSD symptoms over time amid the massive civil unrest in Hong Kong in 2019. In Study 2 (n = 509), we tested the associations of the ability to maintain regular daily routines during stressful events with PTSD symptoms.

2. Study 1

Study 1 aimed to examine changes in the regularity of daily routines before and during widespread civil unrest and the extent to which the changes were associated with the changes in PTSD symptoms. Protests began in June 2019 following the introduction of a controversial bill that would allow the extradition of people from Hong Kong to the People’s Republic of China. The prevalences of probable depression (Hou, Hall et al., 2021) and PTSD (Ni et al., 2020) have been found to be higher during the civil unrest compared to periods without significant social or political unrest in Hong Kong (Lam et al., 2015; Yu et al., 2012). We targeted young adults under 30 years old, who were more likely to attend to the civil unrest (Lee et al., 2019) and had higher levels of stress-related psychiatric symptoms than other age groups (Liang et al., 2021). We expected that regularity of daily routines would be inversely related to a subsequent increase in PTSD symptoms during civil unrest.

2.1. Method

2.1.1. Participants and procedure

Upon obtaining the approval from the Education University of Hong Kong (ref.: 2018-2019-0071), recruitment advertisements were posted on the intranet of the authors’ university in December 2018. Inclusion criteria were age 18–30 years and Chinese fluency. Eligible participants were invited to a computer laboratory and fully apprized of the study before completing the electronic questionnaire. Each participant received an HKD50 (∼USD6.5) supermarket coupon upon completion. Between December 2018 and March 2019 (T1), 287 participants were recruited. Six months after the initial survey, 191 participants (retention rate: 66.6%) finished a follow-up survey between July and September 2019 (T2) and received an HKD50 (∼USD6.5) supermarket coupon for remuneration. Table 1 summarizes the demographic characteristics of the sample.

Table 1. Demographic characteristics of the two samples.

Demographic variable	Sample
	Sample 1	Sample 2
	N = 287	N = 509
Age (years), M (SD)	21.9 (2.3)	33.2 (9.7)
Gender
Male	52 (18.1)	318 (62.5)
Female	235 (81.9)	187 (36.7)
Other	0 (0.0)	4 (0.8)
Annual household income (US$)
0–19,999	–	130 (25.5)
20,000–39,999	–	156 (30.6)
40,000–59,999	–	110 (21.6)
60,000–79,999	–	68 (13.4)
80,000–99,999	–	27 (5.3)
≥ 100,000	–	18 (3.5)
Monthly household income (HK$)
0–9,999	36 (12.5)	–
10,000–19,999	92 (32.1)	–
20,000–29,999	71 (24.7)	–
30,000–39,999	46 (16.1)	–
≥ 40,000	42 (14.6)	–
Marital status
Unmarried	285 (99.3)	281 (55.2)
Married/cohabiting	2 (0.7)	198 (38.9)
Divorced	0 (0.0)	27 (5.3)
Widowed	0 (0.0)	3 (0.6)
Employment status
Full-time	32 (11.1)	373 (73.3)
Part-time	114 (39.7)	80 (15.7)
Unemployed	141 (49.2)	38 (7.5)
Housewife	0 (0.0)	13 (2.6)
Retired	0 (0.0)	5 (1.0)
Educational attainment
High-school diploma or equivalent	8 (2.8)	62 (12.2)
Some college	0 (0.0)	135 (26.5)
College diploma	279 (97.2)	188 (36.9)
Some graduate school	0 (0.0)	31 (6.1)
Graduate degree	0 (0.0)	93 (18.3)
Race (non-mutually exclusive)
Hispanic	0 (0.0)	95 (18.7)
Asian	287 (100)	108 (21.2)
White	0 (0.0)	334 (65.6)
African American	0 (0.0)	63 (12.4)
American Indian	0 (0.0)	32 (6.3)
Hawaiian/other Pacific Islander	0 (0.0)	3 (0.6)

Note: Data are shown as n (%) unless otherwise indicated.

2.1.2. Measures

2.1.2.1. Regularity of daily routines

The Sustainability of Living Inventory (SOLI) was used to measure the regularity of daily routines (Hou et al., 2019). At T1, participants rated how regularly they had performed 42 activities every day on a seven-point scale from 0 (Not at all regular) to 6 (Very much regular) in the past 2 weeks. At T2, the regularity of routines was assessed with respect to a specific time point described in the instruction: ‘Since the beginning of the anti-extradition bill protest, how regularly have you … ?’. Mean scores of the eight daily routines subscales were obtained. Cronbach’s alphas were .83–.91 at T1 and .89–.94 at T2. A detailed list of activities is provided in the Supplementary Material.

2.1.2.2. Trauma exposure

The Life Events Checklist for DSM-5 (LEC-5) was used to assess lifetime trauma exposure (Weathers et al., 2013). At T1, participants reported whether they had directly experienced the 16 traumatic events plus one extreme stressful event specified by themselves (Yes/No). At T2, participants were asked to indicate their highest degree of exposure to the traumatic events on a six-point scale from 0 (Does not apply) to 5 (Happened to me). Total scores were calculated to indicate the overall lifetime trauma exposure.

2.1.2.3. PTSD symptoms

The Chinese Post-traumatic Stress Disorder Checklist – Civilian Version (PCL-C) was used to assess PTSD symptoms (Wu et al., 2008) at T1 and T2. It contains 17 items addressing the three Diagnostic and Statistical Manual of Mental Disorders, 4th Edition (DSM-IV) diagnostic criteria for PTSD (Weathers et al., 1994), namely re-experiencing, avoidance, and hyperarousal. Participants rated the 17 symptoms on a five-point scale from 1 (Not at all) to 5 (Extremely). Summed scores were calculated, with higher scores indicating greater levels of PTSD symptoms. The Cronbach’s alphas were .95 and .96 at T1 and T2, respectively.

2.1.3. Analytical plan

The chi-squared test and Mann–Whitney U test (where appropriate) were used to examine whether there were significant differences in sociodemographic variables between participants who completed and those who did not complete follow-up surveys. No significant difference was identified in gender proportion, years of education, or household income (all p values > .05). Participants who did not complete the follow-up survey were slightly older than those who completed it (mean difference = 0.74 years old, p = .006). An independent samples t-test showed that there was no significant difference in the T1 study variables between individuals who completed the follow-up surveys and those who did not complete them. A latent change score model (LCSM) (McArdle, 2009) was used to address the aim of Study 1. The LCSM is a type of structural equation model that estimates the change in a construct at latent level over time. It can model the changes in multiple domains of interest and establish the associations among the changes. To capture the changes in regular daily routines and PTSD symptoms from T1 to T2 and examine the associations between the changes simultaneously, LCSM was constructed with the full information maximum likelihood (FIML) estimator on the full data set, including individuals with missing data. The eight types of daily routine and PTSD symptoms at T1 and T2 were entered in a single model. Trauma exposure was modelled as an exogenous variable to the outcome variable at respective time points. Model fit was evaluated using a combination of the chi-squared goodness-of-fit test, comparative fit index (CFI), Tucker–Lewis index (TLI), root mean square error of approximation (RMSEA), and standardized root mean square residual (SRMR) (Kievit et al., 2018). A non-significant p value of chi-square, together with CFI and TLI values ≥ .95 and RMSEA and SRMR values ≤ .06, indicates a good fit (Hu & Bentler, 1999). The LCSM was constructed using the lavaan package (Rosseel, 2012) implemented on R software. Figure 1 shows the conceptual diagram of the LCSM.

Figure 1. Conceptual diagram of the latent change score model. PTSD = post-traumatic stress disorder.

2.2. Results

Descriptive statistics (i.e. mean, skewness, kurtosis, and Cronbach’s alpha) of the study variables are summarized in Supplementary Table 1. The current sample reported low levels of trauma exposure according to the binary LEC-5 items (M = 1.70, SD = 1.64) and modest levels of PTSD symptoms (M = 37.47, SD = 14.97) at baseline. The LCSM demonstrated excellent model fit: χ²(34) = 43.118, p = .136, CFI = .995, TLI = .974, RMSEA = .031 (90% CI [.000, .056]), and SRMR = .038. A significant latent increase in PTSD symptoms from T1 to T2 was observed (Δ = 2.030, 95% CI [1.355, 2.706], p < .001; R² = 0.371). Standardized intercepts of the change factors showed significant increases from T1 to T2 in the eight daily routines (Δ = 1.441–2.607, 95% CIs [.730 to 1.934, 2.152 to 3.280], p values < .001; R² = 0.241–0.473). Inverse associations were identified between changes in PTSD symptoms and changes in regularity of the eight daily routines (β = −.427 to −.224, 95% CIs [−.543 to −.359, −.310 to −.090], p values < .01), indicating that the larger the increases in regularity of the eight daily routines from T1 to T2, the smaller the increase in PTSD symptoms. In addition, less enhancement of PTSD symptoms was predicted by T1 higher levels of regular work/study involvement (β = −.184, 95% CI [−.312, −.056], p = .001). In other words, disrupted work/study involvement before the civil unrest could predict greater increase in PTSD symptoms during the civil unrest. PTSD symptoms at baseline predicted lower levels of enhancements of regular healthy eating, duties at home, leisure and social activities, and work/study involvement (β = −.189 to −.127, 95% CIs [−.311 to −.237, −.083 to −.017], p values < .05). Table 2 summarizes the results of the LCSM.

Table 2. Results summary of the latent change score model.

Model	Standardized coefficient [95% CI]
	Routines change	T1 routines → PTSD change	T1 PTSD → Routines change	Routines change ↔ PTSD change
Hygiene	2.607*** [1.934, 3.280]	−.049 [−.178, .080]	−.091 [−.205, .024]	−.224** [−.359, −.090]
Healthy eating	1.835*** [1.144, 2.525]	−.128 [−.281, .025]	−.137* [−.247, −.026]	−.374*** [−.496, −.252]
Sleep	1.649*** [0.977, 2.320]	.096 [−.046, .238]	−.096 [−.203, .011]	−.371*** [−.494, −.249]
Duties at home	1.780*** [1.130, 2.431]	.058 [−.091, .206]	−.186*** [−.288, −.083]	−.288*** [−.418, −.159]
Leisure at home	2.004*** [1.309, 2.699]	−.018 [−.175, .140]	−.132* [−.245, −.019]	−.427*** [−.543, −.310]
Exercising	1.441*** [0.730, 2.152]	.040 [−.099, .179]	−.075 [−.188, .039]	−.417*** [−.536, −.299]
Social activities	1.984*** [1.222, 2.747]	−.055 [−.197, .088]	−.189** [−.311, −.066]	−.329*** [−.455, −.204]
Work/study involvement	1.958*** [1.287, 2.628]	−.184* [−.312, −.056]	−.127* [−.237, −.017]	−.374*** [−.495, −.252]

Note: PTSD = post-traumatic stress disorder; CI = confidence interval.

*p < .05, **p < .01, ***p < .001.

3. Study 2

The findings of Study 1 demonstrated that the sustainment of regular daily routines over time was associated with a lower increase in PTSD symptoms amid a large-scale traumatic event. In Study 2, we examined the associations of the ability to sustain daily routines, operationalized into context sensitivity and responsiveness to feedback (Bonanno & Burton, 2013; Hou, Liang et al., 2021), with PTSD symptoms. The ability to sustain daily routines has been found to be inversely associated with anxiety and depression symptoms in the face of different levels of financial stress (Hou, Liang et al., 2021). We expected that context sensitivity and responsiveness to feedback of sustaining daily routines would be inversely associated with PTSD symptoms.

3.1. Method

3.1.1. Participants and procedure

Upon obtaining ethics approval from the Institutional Review Board for the Protection of Human Subjects at Teachers College, Columbia University (IRB number: 17-351), participants were recruited on MTurk. Inclusion criteria were age 18 years or above and English fluency. A total of 509 participants (187 females) aged between 19 and 73 years (M = 33.2, SD = 9.7) completed the measures and were paid US$3.20 for their participation. Table 1 summarizes the demographic characteristics of the sample.

3.1.2. Measures

3.1.2.1. Ability to sustain regular daily routines

The ability to flexibly sustain regular daily routines was indicated by the performance of participants in a validated vignette-based task (Hou, Liang et al., 2021). In each of six vignettes, a scenario described that an actor was facing financial strain and her or his daily routines were changed accordingly. Participants were asked to rank five standardized responses in reaction to the routine changes. The ranking indicated context sensitivity in each item. If the participant ranked the responses correctly, then she or he would be directed to subquestion 1, ‘If after doing the above things you find that you feel better physically and mentally, how would you prioritize them now?’, and rank the behaviours again. If the participant ranked the responses incorrectly, then she or he would be directed to subquestion 2, ‘If after doing the above things you find that you do not feel better physically and mentally, how would you prioritize them now?’ Rankings on the two subquestions indicated responsiveness to feedback. Spearman’s rank correlation coefficient was used to assess how well participants’ rankings matched with the standard answers. Context sensitivity was indicated by averaging correlation coefficients in all first rankings, and responsiveness to feedback by averaging correlations coefficients in all second rankings. Higher coefficients indicated higher levels of context sensitivity or responsiveness to feedback.

3.1.2.2. Trauma exposure

The LEC-5 was used to assess lifetime trauma exposure (Weathers et al., 2013). Participants were asked to indicate their highest degree of exposure to 16 traumatic events plus one other event specified by themselves on a six-point scale from 0 (Does not apply) to 5 (Happened to me). A summed score was calculated to indicate overall lifetime trauma exposure.

3.1.2.3. PTSD symptoms

The PCL-C was used to assess PTSD symptoms, as in Study 1 (Weathers et al., 1994). Each symptom was evaluated on a five-point scale from 1 (Not at all) to 5 (Extremely). A total score was calculated to represent the overall severity of PTSD symptoms, with higher scores indicating greater post-traumatic stress symptomatology. Cronbach’s alpha was .97.

3.1.3. Analytical plan

Hierarchical regression was performed using jamovi version 2.3 (The jamovi project, 2023). In step 1, demographic variables were entered in the model, followed by entering the trauma exposure in step 2, and context sensitivity as well as responsiveness to feedback in step 3. To avoid multicollinearity and facilitate meaningful interpretations of the results, raw scores of study variables were centred among sample means. The variance inflation factors (VIFs) were obtained to evaluate the multicollinearity of the predictors.

3.2. Results

Descriptive statistics of the study variables are summarized in Table 3. The results showed that trauma exposure accounted for an additional 9.7% of the variance of PTSD symptoms, while context sensitivity and responsiveness to feedback explained 10.9% of the variance. The VIFs were below 1.798, indicating non-multicollinearity among the predictors (O’brien, 2007). A significant positive association was found between trauma exposure and PTSD symptoms (β = .280, 95% CI [.208, .353], p < .001). PTSD symptoms were inversely associated with context sensitivity (β = −.285, 95% CI [−.379, −.190], p < .001) and responsiveness to feedback (β = −.096, 95% CI [−.189, −0.003], p = .044). The results are summarized in Table 4.

Table 3. Descriptive statistics and correlations of the study variables in Study 2.

Variable	M (SD)	Skewness	Kurtosis	Correlation with PTSD symptoms
Trauma exposure	26.85 (19.60)	0.538	−0.534	.362***
PTSD symptoms	35.77 (17.44)	0.755	−0.630	–
Context sensitivity	0.51 (0.30)	−0.688	−0.181	−.452***
Responsiveness to feedback	0.43 (0.27)	−0.716	0.037	−.369***

Note. PTSD = post-traumatic stress disorder.

***p < .001; – = not applicable.

Table 4. Regression models of regulatory flexibility in sustaining regular daily routines and PTSD symptoms.

Variable	Step 1			Step 2			Step 3
	β	p	95% CI	β	p	95% CI	β	p	95% CI
Gender†	−.187	.037	[−.362, −.011]	−.123	.145	[−.289, .043]	.004	.959	[−.152, .160]
Age	−.186	< .001	[−.271, −.101]	−.188	< .001	[−.268, −.108]	−.135	.0005	[−.209, −.060]
Educational level	.279	< .001	[.197, .360]	.237	< .001	[.160, .315]	.177	< .001	[.104, .250]
Trauma exposure				.317	< .001	[.239, .394]	.280	< .001	[.208, .353]
Context sensitivity							−.285	< .001	[−.379, −.190]
Responsiveness to feedback							−.096	.044	[−.189, −.003]

Note: PTSD = post-traumatic stress disorder; CI = confidence interval.

†Gender: 0 = male, 1 = female and other.

4. Discussion

This study examined the associations between regularizing daily routines and PTSD symptoms using different methods in two studies. In line with our expectation, Study 1 showed that increased regularity of daily routines was inversely associated with increased PTSD symptoms during a period of unrest. In Study 2, a greater ability to maintain regular daily routines during stress was associated with lower levels of PTSD symptoms, consistent with previous evidence on the inverse association between regulatory flexibility and PTSD symptoms (Levy-Gigi et al., 2020) and the inverse associations of context sensitivity in sustaining regular routines with anxiety and depression symptoms, with regard to chronic financial strain (Hou, Liang et al., 2021).

Our prospective data suggest that maintaining or enhancing the regularity of daily routines over time, especially during mass trauma, i.e. widespread civil unrest, could buffer the PTSD symptoms of the affected populations. This is consistent with previous evidence on the importance of maintaining or restoring pre-disaster daily living in reducing psychological distress over an extended period of time following a major disaster (Goodwin et al., 2020), depressive symptoms during the COVID-19 pandemic (Giuntella et al., 2021), and PTSD symptoms during ongoing terrorism (Pat-Horenczyk, 2005). A majority of individuals have been found to exhibit a resilient response, characterized by enduring low levels of mental health problems during and following traumatic and chronic life events (Galatzer-Levy et al., 2018; Schäfer et al., 2022). The present study extended previous works by delineating the behavioural process in which less emergence of PTSD symptoms was associated with sustainable engagement in diverse daily routines. This is also in line with the sustainability pathway of psychological resilience, which emphasizes the preservation of positive functioning, including engagement in life tasks despite stressful encounters (Hobfoll et al., 2012; Zautra et al., 2010). Regular exercise, socializing, leisure activities, and work/study involvement have been proposed as resilience resources that are conducive to adaptive responses to stressful events (Zautra et al., 2010). There is also evidence showing a positive association between disrupted sleep routines and overall PTSD symptomatology, either with (e.g. Iwadare et al., 2014; Straus et al., 2015) or without sleep-related symptoms of PTSD (e.g. Schenker et al., 2023). The current study is one of the first to systematically and simultaneously investigate the associations between diverse daily routines and PTSD symptoms using validated and standardized instruments.

Traumatic and chronic stress is usually associated with circumstances and environments that restrict individuals from engaging in important daily activities (Giuntella et al., 2021; Parks et al., 2018). The present study demonstrated evidence of the mental health benefits of the ability to flexibly sustain regular daily routines despite stressful circumstances. Our study could supplement the current evidence on the potentially important role of regularizing daily routines within psychosocial interventions such as CBSRT (Haynes et al., 2016, 2020). To begin with, based on daily monitoring, changes in primary and secondary routines of patients with PTSD could be tracked and classified as either ‘disrupted’ or ‘terminated’. Then, regulatory strategies such as consolidation and replacement in response to the changes in routines could be implemented corresponding to the contextual demands. Adaptive priorities of sustaining primary over secondary routines and fixing disruption over termination should be considered in the process of restoring the disrupted rhythms. In addition, our findings could extend existing empirical investigations and lifestyle interventions that focus primarily on sleep, diet, and exercise (Firth et al., 2020; Sarris et al., 2014). Interventions and psychoeducational programmes could be tailor-made to enhance the regularities of other important daily routines such as household chores, leisure at home, and work/study involvement to aid better adjustment across different forms of trauma (Hou et al., 2019; Hou, Liang et al., 2021).

Most, if not all, existing studies about the mental health implications of daily routines were conducted using the SRM (Monk et al., 1991, 2002). Within this line of work, lifestyle regularity measured by the SRM refers to the regularity of overall daily life without considering different kinds of routines and activities and their associations with mental health outcomes. The same level of lifestyle regularity may be represented by different numbers and types of daily activities. Therefore, the value and effect of a specific type of daily activity on improving mental health have been less studied. Our findings attempted to fill these research gaps by demonstrating the associations between eight daily routines and PTSD symptoms in Study 1. A balanced lifestyle pattern characterized by maintaining the regularity of diverse daily routines may outperform lifestyle patterns containing only a few regular routines in term of protecting mental health against the negative consequences of stressful circumstances (Matuska & Christiansen, 2008). Future research investigating the mental health benefits of regular daily routines should consider the diversity of daily routines together with the effect of specific daily activities.

4.1. Limitations and future directions

A few limitations should be noted. First, Study 1 was conducted among younger adults and with a majority of females, who have been found to be more likely to participate in the civil unrest and to be more affected emotionally by the unrest (Lee et al., 2019). Caution is warranted in interpreting and generalizing the findings to older people or those who were less affected by the unrest. Secondly, the PCL-C is a DSM-IV-based measurement, and future studies could replicate our analysis with the PCL for DSM-5 (PCL-5) (Blevins et al., 2015). Nevertheless, our findings may be robust across these measures given the high correlation between the sum scores of PCL-C and PCL-5 that has been consistently observed in different comparison studies (LeardMann et al., 2021; Moshier et al., 2019). Thirdly, other mental health problems, including anxiety and depressive symptoms, were not assessed in Study 2. It will be important for future research to investigate whether regulatory flexibility in sustaining regular routines independently and specifically relates to PTSD symptoms or to other mental health disorders at the same time. In addition, the cross-sectional nature of our data precludes a directional interpretation of the associations of PTSD symptoms with context sensitivity and responsiveness to feedback. Context sensitivity and responsiveness to feedback were interpreted as predictors and PTSD symptoms as outcomes on conceptual and theoretical bases (Bonanno & Burton, 2013). It is also likely that people with higher levels of PTSD symptoms could have lower levels of context sensitivity and responsiveness to feedback. Lastly, the vignette-based approach was designed for changes in regular daily routines, with the assumption that financial strain is a common stressor that could have both traumatic and chronic mental health impacts on individuals (Johnson et al., 2020; Krause, 1987). Future studies could investigate the relevance of sustaining daily routines within specific stressors to trauma and PTSD, although the ability of detecting changes in daily routines and giving appropriate responses to them is likely to be generalizable across different stressful conditions rather than being specific to a particular encounter (Bonanno & Burton, 2013). Scenarios nonetheless could be tailor-made for the most disturbing events with reference to a particular trauma exposure.

5. Conclusions

Notwithstanding these limitations, the present study supplements empirical evidence that the sustainment of regular daily routines (i.e. hygiene, healthy eating, sleep, duties at home, exercising, leisure and social activities, work/study involvement) amid stressful events and regulatory flexibility in sustaining regular daily routines are inversely associated with PTSD symptoms. Daily changes in the primary and secondary routines of patients with PTSD could be tracked and classified as either ‘disrupted’ or ‘terminated’. Then, patients could be instructed on regulatory strategies such as consolidation and replacement in response to the changes in routines and the contextual demands. Adaptive priorities of sustaining primary over secondary routines and fixing disruption over termination should be considered in the process of restoring the disrupted rhythms. Our research advocates further investigation into the mental health benefits of daily routines, considering the diversity of everyday activities together with the unique effect of specific types of daily routine. Interventions with the direct focus on the role of daily living could promote psychological resilience during and after trauma exposure.

Acknowledgements

This research was supported by Fulbright-RGC Hong Kong Senior Research Scholar Award [grant number R9401] and General Research Fund [grant number 18600320], Research Grants Council, University Grants Committee, Hong Kong SAR, China, both to WKH, an NIH grant from the National Institutes of Health [grant number R01MH091034] to GAB, and an internal research grant from the Education University of Hong Kong, Hong Kong SAR, China [grant number RG84/2018-2019R] to WKH. The funding sources were not involved in the study design, data analysis or interpretation, or preparation and submission of this manuscript.

Data availability statement

The data that support the findings of this study are available from the corresponding author upon reasonable request.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the National Institutes of Health [grant number R01MH091034]; The Education University of Hong Kong [grant number RG84/2018-2019R]; Research Grants Council, University Grants Committee, Hong Kong SAR, China [grant numbers R9401, 18600320].