Wai Kwong Tang

Background: This study aimed to investigate whether individuals with trichotillomania (TTM) are at a higher risk of engaging in self-harm behaviors compared to those without TTM. Methods: In this matched cohort study, we analyzed electronic health records of all patients admitted to public hospitals in Hong Kong from 1 January 1993 to 31 December 2022. We identified a TTM cohort of 285 patients and a comparison cohort of 285 individuals. All participants were followed up until they received a diagnosis of self-harm, died from other causes, or until the end of 2023, whichever came first. To assess the risk of self-harm following TTM onset, Cox proportional hazards regression models were applied. Results: Throughout the 30-year study period, the number of individuals who exhibited self-harm behavior in the TTM and comparison groups was 8 (2.8%) and 8 (2.8%), respectively. The TTM and comparison groups had similar proportions of subjects who inflicted self-harm (χ² = 0.00, p = 0.977). The incidence of self-harm was 26.00 and 26.92 per 10,000 person-years in the TTM and comparison groups, respectively. Compared with the comparison group, the adjusted hazard ratio for self-harm in the TTM group was 1.44 (95% confidence interval, 0.45–4.61). Conclusions: TTM is not associated with an increased risk of self-harm. Future research is necessary to replicate our findings and more fully elucidate the potential unique risk factors for self-harm in these patients.

Rationale: Post-stroke fatigue (PSF) is an issue among stroke survivors that often impedes their rehabilitation progress. Treating PSF is challenging, and pharmacological interventions often prove ineffective. Aims: The aim of this study was to examine the effect of tDCS on PSF. Sample size: Thirty-four participants aged 30 to 80 with chronic stroke were recruited and randomly assigned to one of two groups, with 17 participants in each group. Methods and design: This study was a double-blind randomized controlled trial. The sham group received sham tDCS, while the treatment group received active tDCS. The active tDCS treatment consisted of applying a constant 2-mA current through a 5 cm × 5 cm anodal electrode placed over the C3 or C4 positions (motor cortex) of the contralateral hemisphere of the scalp, with the cathodal electrode placed on the ipsilateral arm. The participants received two 20-min sessions of this treatment, separated by a 10-min interval, each day for 5 consecutive days. Sham tDCS involved the same setup but with only 30 s of constant current at the beginning and end of each 20-min session. Follow-up assessments were conducted over an 8-week period. The effects of tDCS were calibrated using an analysis of covariance approach, with baseline Modified Fatigue Impact Scale (MFIS) scores, age, and education as covariates. The inclusion criteria were (1) either sex; (2) age 30–80 years; (3) prior stroke diagnosis verified through brain imaging (computed tomography scan/magnetic resonance imaging); (4) Chinese ethnicity and Cantonese proficiency; (5) willingness and ability to provide informed consent; (6) presence of PSF (Fatigue Severity Scale score ≥ 4.0); and (7) at least 6 months post-stroke. Study outcome: The primary outcome was the change in fatigue severity, assessed using the MFIS. Results: One participant in the sham group dropped out. After the intervention, no significant changes were observed in MFIS scores at any of the follow-up timepoints ( p > 0.05). Conclusion: We found no evidence that the use of tDCS improves PSF. Further research is needed to explore the potential of this non-invasive brain stimulation method for the treatment of PSF. Clinical trial registration: https://clinicaltrials.gov/ , identifier NCT04238260; https://www.chictr.org.cn/ , identifier ChiCTR2100052515.

Background and aims: Mindfulness‐based relapse prevention (MBRP) has been shown to be beneficial to individuals with substance use disorder (SUD) in the West. The current pilot study aimed at testing the feasibility of MBRP in a Chinese population. Design: This pilot study adopted a design of randomized controlled trial comparing MBRP with treatment‐as‐usual group (TAU). Setting: Participants were recruited from residential detox centers, community addiction counseling centers and substance abuse clinics specialized addiction treatment clinics in Hong Kong. Participants: A total of 81 adults (85.2% male) with SUD (illicit drugs only) were recruited. Interventions: The intervention group participants ( n = 41) attended a 1‐hour orientation session followed by 2‐hour weekly MBRP sessions for 8 weeks, delivered by a qualified MBRP teacher. The TAU group participants ( n = 40) continued their service received from their referral agency. (After completion of all study assessments they were offered the same 8‐week MBRP course.) Measurements: Feasibility was measured by attendance, course satisfaction and retention rate. Participants' change in substance use and other related outcomes were captured by self‐reported drug use, urine drug tests and a list of psychometric scales at baseline, immediately after MBRP and 3‐ and 6‐month follow‐up. Findings: The MBRP course satisfaction was high, and the attendance (57.4%) and retention rates (63.4%–85.4%) were comparable to previous trials. No statistically significant differences were observed between the MBRP and TAU groups for any outcomes, including craving, depression, anxiety, mindfulness and health‐related quality of life; however, improvement trends were noticed in the MBRP group in self‐efficacy in managing high‐risk situations at post intervention, as well as in addiction severity and psychological flexibility at the 6‐month follow‐up. Conclusions: Mindfulness‐based relapse prevention was shown to be feasible for substance use disorder treatment in a Chinese population. In this small study there was only limited evidence of abstinence efficacy, and no evidence of a benefit on other secondary outcomes.

Background: This study aimed to examine if individuals diagnosed with dissociative disorder (DD) are at a higher risk of suicidal acts compared to individuals without DD. Methods: We conducted a matched cohort study by examining electronic health records of patients admitted to Hong Kong public hospitals between January 1, 1993, through December 31, 2022. The study included 716 patients with DD and a matched comparison cohort of 716 individuals. Participants were tracked until they either received a diagnosis of suicidal acts, died from other causes, or until the end of 2023, whichever happened first. Cox proportional hazards regression models were applied to determine the risk of suicidal acts following DD onset. Results: During the 30-year study period, 87 individuals (12.2%) in the DD cohort and 29 individuals (4.1%) in the comparison cohort exhibited suicidal acts, with the difference being statistically significant (χ ² = 25.21, p = 0.0001). The incidence rates of suicidal acts were 86.7 and 27.3 per 10,000 person-years for the DD and comparison cohorts, respectively. After adjustment, the hazard ratio for suicidal acts in the DD cohort compared with the comparison cohort was 1.89 (95% confidence interval, 1.17–3.06). Conclusions: DD is linked to a heightened risk of suicidal acts. Future research is required to replicate these findings and to more comprehensively identify the specific risk factors contributing to suicidal acts in this patient population.

Background: This study investigated whether individuals with kleptomania (KTM) are at higher risk of engaging in self-harm behaviors than individuals without KTM. Methods: In this matched cohort study, we analyzed the electronic health records of all patients admitted, for any indication, to public hospitals in Hong Kong between 1 January 1993 and 31 December 2022. We selected a KTM cohort consisting of 152 patients and a comparison cohort comprising 152 subjects. Participants were observed until they received a self-harm diagnosis, died from other causes, or reached the end of 2023, whichever occurred first. The Cox proportional hazards regression model was used to calculate the self-harm risk since KTM onset. Results: Over a 30-year study period, the number of individuals who engaged in self-harm in the KTM and comparison groups was ten (6.6%) and eight (5.3%), respectively. Both groups showed similar proportions of individuals who inflicted self-harm (χ² = 0.49, p = 0.834). The self-harm incidence was 48.4 and 44.5 per 10,000 person-years in the KTM and comparison groups, respectively. The adjusted hazard ratio for self-harm in the KTM group was 0.49 (95% confidence interval, 0.16–1.48) relative to the comparison group. Conclusions: KTM is not associated with an increased self-harm risk. Future studies should replicate our findings and further delineate any distinct risk factors for self-harm in these patients.

Objective: This study was conducted to determine whether individuals with body dysmorphic disorder (BDD) have an increased risk of self-harm behaviors compared with those without BDD. Methods: In this matched cohort study, we reviewed the electronic health records of all patients admitted for any reason to Hong Kong public hospitals between January 1, 1993, and December 31, 2022. We selected a cohort of 71 patients with BDD and a comparison cohort of 71 patients without BDD. Participants were followed until a diagnosis of self-harm, death from other causes, or the end of 2023, whichever occurred first. Cox proportional hazards regression models were used to assess the risk of self-harm since the onset of BDD. Results: During the 30-year study period, 2 (2.8%) individuals in the BDD group and 3 (4.2%) in the comparison group exhibited self-harm behavior. The proportion of individuals engaging in self-harm was similar between the groups (χ ² = 0.25, p = 0.62). The incidence of self-harm was 22.5 and 34.6 per 10, 000 person-years in the BDD and comparison groups, respectively. The adjusted hazard ratio for self-harm was 0.63 (95% confidence interval, 0.08–4.56) in the BDD group compared with the comparison group. Conclusions: BDD is not associated with an increased risk of self-harm. Future studies are needed to replicate our findings and further identify potential risk factors for self-harm in patients with BDD.

Objective: This study aimed to ascertain whether individuals diagnosed with hypochondriasis (HYPO) exhibit a heightened risk of self-harming behaviors in comparison to those without the disorder. Methods: In this matched cohort study, we conducted a review of electronic health records of all patients admitted to Hong Kong public hospitals for any reason between January 1, 1993, and December 31, 2022. A HYPO cohort comprising 906 patients was identified, along with a comparison cohort of 906 matched subjects. All participants were followed until the occurrence of a self-harm diagnosis, death from other causes, or the end of 2023, whichever came first. The risk of self-harm from the onset of HYPO was estimated using Cox proportional hazards regression models and competing risk analysis. Results: Over the 30-year duration of the study, the number of individuals exhibiting self-harm behavior was 51 (5.6%) in the HYPO group and 49 (5.4%) in the comparison group. Both groups demonstrated comparable proportions of subjects engaging in self-harm (χ ² = 0.01, p = 0.927). The incidence rates of self-harm were 43.4 per 10,000 person-years in the HYPO group and 38.2 per 10,000 person-years in the comparison group. After adjustment, the hazard and subhazard ratio for self-harm in the HYPO group relative to the comparison group was 0.87 (95% confidence interval, 0.55–1.38) and 0.84 (95% CI, 0.53–1.34; p = 0.474), respectively. Conclusions: We did not find significant evidence for an elevated risk of self-harm associated with HYPO. Future research is warranted to replicate these findings and to more comprehensively identify the potential unique risk factors for self-harm in this patient population.

Introduction: Metacognition (MC) impairment is prevalent among stroke survivors but is frequently undiagnosed and untreated. MC impairment hinders stroke survivors’ ability to recognize their deficits, causing them to engage in activities that exceed their capabilities, set unrealistic performance goals and fail to use adaptive compensatory strategies. The present study will evaluate the clinical, neuropsychological and MRI correlates of MC impairment in a cohort of stroke survivors. The secondary objective is to describe the 12-month course of MC impairment.Methods and analysis: The current study is a prospective cohort study. We will recruit 246 subjects. The project duration is 36 months. Subjects and carers will receive a detailed assessment at a research clinic at three, nine and 15 months after stroke onset (T1/T2/T3). The Chinese version of the Self-Awareness of Deficits Interview (SADI) will be completed by each subject. MC impairment is defined as any SADI subscale score of 2 or more. Potential covariate will be measured as well. Tests of executive functioning will be administered as well. Patients will be examined by MRI within 1 week after the onset of stroke. A stepwise logistic regression will be performed to assess the importance of lesions in the regions of interest. To examine neuropsychological functions in MC impairment, regression analysis of the SADI total and subscale scores will be performed using the significantly correlated neuropsychological functions as predictors. To examine the predictors of MC impairment remission, the demographic, clinical and MRI variables of remitters and non-remitters at T2/T3 will be examined by logistic regression.Discussion: This project will be the first longitudinal study on MC impairment in stroke survivors. The results will shed light on the association between prefrontal cortex and subcortical lesions and MC impairment risk, symptom severity and outcome.

Background: Poststroke irritability (PSI) is common among stroke survivors and can lead to a poor quality of life, difficulties in social interactions, criticism from caregivers, and caregiver stress. The planned study will evaluate the clinical, neuropsychological, and magnetic resonance imaging (MRI) correlates of PSI in a cohort of stroke survivors. In addition, the study will examine the 15-month progression of PSI.Methods: This will be a prospective cohort study that will recruit 285 participants. Participants and their caregivers will undergo detailed assessments at a research clinic at 3, 9, and 15 months after stroke onset (T1/T2/T3). The irritability/lability subscale of the Chinese version of the Neuropsychiatric Inventory (CNPI) will be completed by caregivers. Potential covariates will also be measured. Patients will undergo MRI, including diffusion-weighted imaging, within 1 week of stroke onset. A stepwise logistic regression will be performed to evaluate the importance of lesions in the regions of interest (ROIs) along with other significant variables identified in univariate analyses. These analyses will be repeated for patients with and without PSI at T2 and T3. Repeated measures analysis of covariance (ANCOVA) will be used to assess changes in CNPI scores for the entire sample. In ANCOVA analyses, the frequency of infarcts in the ROIs will be treated as the predictor.Discussion: This will be the first MRI study on PSI in stroke survivors. The findings will provide insights into the association of the orbitofrontal cortex, anterior cingulate cortex, anterior temporal lobe, insula, amygdala, thalamus, and basal ganglia lesions with the risk of PSI.