Relationship Between Current Depressive Symptoms and Telomere Length in a Large, Multiethnic Sample.

OBJECTIVE: Previous research has suggested that depressive symptoms may be associated with telomere length; however, findings have been mixed, and few studies have sought to generalize the results beyond samples of white individuals. The present study, conducted from August 2013 through August 2015, sought to examine the relationship between depressive symptoms and leukocyte telomere length in a large (N = 2,710), multiethnic sample (African American, white, Hispanic) and to determine if this relationship differed across ethnic/racial groups. Analyses were based on data taken from the Dallas Heart Study, a recent epidemiologic-style, population-based study of adults from Dallas County, Texas. METHODS: Depressive symptoms were measured using the Quick Inventory of Depressive Symptomatology, and leukocyte telomere length was measured using a quantitative polymerase chain reaction technique. Analyses of the relationship between depressive symptoms and telomere length were conducted using multiple linear regression models. RESULTS: Among the whole sample, there was no significant relationship between depressive symptoms and telomere length in either a basic (ß = -0.025, P = .190) or an adjusted (ß = -0.015, P = .443) model. However, among non-Hispanic white participants, depressive symptoms were significantly associated with telomere length in both basic (ß = -0.083, P = .014) and adjusted (ß = -0.066, P = .049) models. CONCLUSIONS: These findings suggest that ethnic/racial identification may be a factor in the relationship between depressive symptoms and telomere length and could impact the generalizability of previous research.

Citicoline in addictive disorders: a review of the literature.

BACKGROUND: Citicoline is a dietary supplement that has been used as a neuroprotective agent for neurological disorders such as stroke and dementia. Citicoline influences acetylcholine, dopamine, and glutamate neurotransmitter systems; serves as an intermediate in phospholipid metabolism; and enhances the integrity of neuronal membranes. Interest has grown in citicoline as a treatment for addiction since it may have beneficial effects on craving, withdrawal symptoms, and cognitive functioning, as well as the ability to attenuate the neurotoxic effects of drugs of abuse. OBJECTIVES: To review the literature on citicoline's use in addictive disorders. METHODS: Using PubMed we conducted a narrative review of the clinical literature on citicoline related to addictive disorders from the years 1900-2013 using the following keywords: citicoline, CDP-choline, addiction, cocaine, alcohol, substance abuse, and substance dependence. Out of approximately 900 first hits, nine clinical studies have been included in this review. RESULTS: Most addiction research investigated citicoline for cocaine use. The findings suggest that it is safe and well tolerated. Furthermore, citicoline appears to decrease craving and is associated with a reduction in cocaine use, at least at high doses in patients with both bipolar disorder and cocaine dependence. Limited data suggest citicoline may also hold promise for alcohol and cannabis dependence and in reducing food consumption. CONCLUSIONS: Currently, there is limited research on the efficacy of citicoline for addictive disorders, but the available literature suggests promising results. Future research should employ larger sample sizes, increased dosing, and more complex study designs.

Effects of nicotine on attention and inhibitory control in healthy nonsmokers.

Nicotine improves cognitive functioning in smokers and psychiatric populations, but its cognitive-enhancing effects in healthy nonsmokers are less well understood. Nicotine appears to enhance certain forms of cognition in nonsmokers, but its specificity to subtypes of cognition is not known. This study sought to replicate and extend previous findings on the effects of nicotine on cognitive performance in healthy nonsmokers. Healthy young adults (N = 40, 50% women) participated in a placebo-controlled, double-blind, repeated measures experiment examining the effects of 7 mg transdermal nicotine or placebo. Participants completed tests of attention (Attention Network Test), behavioral inhibition (stop signal task, Stroop test), reward responsiveness (signal detection task), and risk-taking behavior (Balloon Analogue Risk Task). Physiological (heart rate, blood pressure) and subjective (Profile of Mood States, Drug Effects Questionnaire) measures were also obtained. Nicotine significantly improved performance only on the Stroop test, but it impaired performance on one aspect of the Attention Network Test, the orienting effect. Nicotine produced its expected effects on physiologic and subjective measures within the intended time course. The findings of this study contribute to a growing literature indicating that nicotine differentially affects specific subtypes of cognitive performance in healthy nonsmokers.