Shih-Hsien Lin

Availability of dopamine and serotonin transporters in opioid-dependent users—a two-isotope SPECT study

Rationale and objectiveThe aims of this study were to examine the differences between 32 opioid-dependent users treated with a very low dose of methadone or undergoing methadone-free abstinence and 32 controls.MethodsSPECT analysis using [99mTc] TRODAT-1 to assess striatal dopamine transporter (DAT) availability and [123I] ADAM to assess midbrain serotonin transporter (SERT) availability were performed.ResultsLower striatal DAT and midbrain SERT availabilities were noted in low-dose methadone users. History of metamphatamine use was associated with the lower striatal DAT. The striatal DAT of methadone-free abstainers was also lower than controls. The midbrain SERT availability tended to be higher in the methadone-free abstainers than the low-dose methadone users. The severity of depressive symptoms was negatively correlated with midbrain SERT availability in the opioid users.ConclusionThe availability of striatal DAT tended to be, and the availability of midbrain SERT was, lower in the opioid users. History of metamphatamine use may confound the difference in straital DAT between controls and opioid users, as midbrain SERT and depressive symptoms are also associated with opioid use and abstinence.

Serotonin and mental disorders: a concise review on molecular neuroimaging evidence.

Serotonin is one of the most important neurotransmitters influencing mental health and, thus, is a potential target for pharmaco-logical treatments. Functional neuroimaging techniques, such as positron-emission tomography (PET) and single photon emission computed tomography (SPECT), could provide persuasive evidence for the association between mental disorders and serotonin. In this concise review, we focus on evidence of the links between serotonin and major depressive disorders, as well as other mood disorders, anxiety disorders, schizophrenia, addiction, attention deficit hyperactivity disorder (ADHD), and autism.

The economic cost of heroin dependency and quality of life among heroin users in Taiwan.

Heroin dependence may cause an economic burden and has an impact on quality of life (QOL). However, assessments of economic cost are scarce and the relationship between economic cost and QOL is unclear in the Asian population. In the present study, an established questionnaire was modified to assess the economic cost and its association with QOL. A total of 121 volunteer subjects in a methadone maintenance therapy programme and 157 normal controls were enrolled. The total economic cost of heroin dependency is US

Role of DRD2 and ALDH2 genes in bipolar II disorder with and without comorbid anxiety disorder

18,310 per person-year. The direct cost is US

Association Between Cholesterol Plasma Levels and Craving Among Heroin Users

11,791 per person-year (64% of the total cost), mostly consisting of the cost of heroin and other illegal drugs. The indirect cost is US

Associations among hypothalamus-pituitary-adrenal axis function, novelty seeking, and retention in methadone maintenance therapy for heroin dependency.

6519 (36% of the total cost) per person-year, most of which arises from productivity loss caused by unemployment and incarceration. The QOL of heroin-dependent patients is poorer than that of healthy controls in all domains. The overall QOL is negatively related to direct cost and total cost. The economic cost of heroin dependency is huge, equal to 1.07 times the average gross domestic product per capita. Reduction of the economic cost to society and the economic burden for heroin users is important.

Gender difference in antidepressant-related sexual dysfunction in Taiwan

The presence of comorbid anxiety disorders (AD) and bipolar II disorders (BP-II) compounds disability complicates treatment, worsens prognosis, and has been understudied. The genes involved in metabolizing dopamine and encoding dopamine receptors, such as aldehyde dehydrogenase 2 (ALDH2) and dopamine D2 receptor (DRD2) genes, may be important to the pathogenesis of BP-II comorbid with AD. We aimed to clarify ALDH2 and DRD2 genes for predisposition to BP-II comorbid with and without AD. The sample consisted of 335 subjects BP-II without AD, 127 subjects BP-II with AD and 348 healthy subjects as normal control. The genotypes of the ALDH2 and DRD2 Taq-IA polymorphisms were determined using polymerase chain reactions plus restriction fragment length polymorphism analysis. Logistic regression analysis showed a statistically significant association between DRD2 Taq-I A1/A2 genotype and BP-II with AD (OR=2.231, P=0.021). Moreover, a significant interaction of the DRD2 Taq-I A1/A1 and the ALDH2*1*1 genotypes in BP-II without AD was revealed (OR=5.623, P=0.001) compared with normal control. Our findings support the hypothesis that a unique genetic distinction between BP-II with and without AD, and suggest a novel association between DRD2 Taq-I A1/A2 genotype and BP-II with AD. Our study also provides further evidence that the ALDH2 and DRD2 genes interact in BP-II, particularly BP-II without AD.

Quantifying Midbrain Serotonin Transporter in Depression: A Preliminary Study of Diagnosis and Naturalistic Treatment Outcome

Objective:Lipids may play some roles in the central nervous system functions that are associated with drug addiction. To date, cholesterol is known to influence relapse of cocaine use. However, the relationship between cholesterol and heroin craving is unclear. This study examined the concurrent association between cholesterol and craving. Method:The serum lipid levels of 70 heroin users who were undergoing or had undergone a methadone maintenance therapy were measured. Their craving and demographic data were assessed. Results:Total cholesterol and low-density lipoprotein cholesterol are negatively associated with craving before (r = −0.33, P < 0.01, and r = −0.36, P < 0.01, respectively) and after controlling for the effects of potential confounders (&bgr; = −0.38, P < 0.01, and &bgr; = −0.42, P < 0.01, respectively). Conclusions:Cholesterol could be associated with the cognitive aspect of craving and may be a potential marker to predict risk of drug relapse.

The Association between the Level of Plasma Oxytocin and Craving among Former Heroin Users

Objective:The efficacy of methadone maintenance therapy for heroin dependence is compromised by the low retention rate. Hypothalamus–pituitary–adrenal (HPA) axis function, which is associated with stress response, and novelty seeking (NS), a personality trait associated with low dopaminergic activity, may play roles in retention. Method:We conducted a prospective study in which HPA axis function and NS were assessed by the dexamethasone suppression test and the Tridimensional Personality Questionnaire at baseline, respectively. The retention rate was assessed at the half- and 1-year points of methadone maintenance therapy. Results:A low suppression rate of dexamethasone suppression test (D%) was associated with a high level of NS. A low D% was associated with half-year dropout, whereas a high level of NS was associated with 1-year dropout. Survival analysis confirmed that D% and NS were significant time-dependent covariates for retention. Conclusion:The findings showed that HPA axis function and NA were associated with retention at different time points.

The dopamine hypothesis of social support

OBJECTIVEnSexual dysfunction accompanied by depression may be altered by antidepressants. The effects of antidepressants on sexual dysfunction among males and females remain to be investigated.nnnMETHODSnThree groups of subjects, drug-free patients with depression (N=125), medicated patients with depression (N=145) and healthy volunteers (N=255), were recruited. A Chinese version of the Changes in Sexual Functioning Questionnaire was employed to assess sexual function as the primary outcome.nnnRESULTSnDrug-free depressed females and medicated depressed males had more sexual dysfunction than healthy controls. The desire for sexual behaviors among healthy females and medicated depressed females was higher than that of drug-free depressed females.nnnCONCLUSIONnDepression and antidepressants may have different impacts on the sexual function of males and females.