Viviana Guajardo
University of Chile
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The Lancet | 2007
Graciela Rojas; Rosemarie Fritsch; Jaime Solís; Enrique Jadresic; Cristóbal Castillo; Marco González; Viviana Guajardo; Glyn Lewis; Timothy J. Peters; Ricardo Araya
BACKGROUND The optimum way to improve the recognition and treatment of postnatal depression in developing countries is uncertain. We compared the effectiveness of a multicomponent intervention with usual care to treat postnatal depression in low-income mothers in primary-care clinics in Santiago, Chile. METHODS 230 mothers with major depression attending postnatal clinics were randomly allocated to either a multicomponent intervention (n=114) or usual care (n=116). The multicomponent intervention involved a psychoeducational group, treatment adherence support, and pharmacotherapy if needed. Usual care included all services normally available in the clinics, including antidepressant drugs, brief psychotherapeutic interventions, medical consultations, or external referral for specialty treatment. The primary outcome measure was the Edinburgh postnatal depression scale (EPDS) score at 3 and 6 months after randomisation. Analysis was by intention to treat. This study is registered with ClinicalTrials.gov, number NCT00518830. FINDINGS 208 (90%) of women randomly assigned to treatment groups completed assessments. The crude mean EPDS score was lower for the multicomponent intervention group than for the usual care group at 3 months (8.5 [95% CI 7.2-9.7] vs 12.8 [11.3-14.1]). Although these differences between groups decreased by 6 months, EPDS score remained better in multicomponent intervention group than in usual care group (10.9 [9.6-12.2] vs 12.5 [11.1-13.8]). The adjusted difference in mean EPDS between the two groups at 3 months was -4.5 (95% CI -6.3 to -2.7; p<0.0001). The decrease in the number of women taking antidepressants after 3 months was greater in the intervention group than in the usual care group (multicomponent intervention from 60/101 [59%; 95% CI 49-69%] to 38/106 [36%; 27-46%]; usual care from 18/108 [17%; 10-25%] to 11/102 [11%; 6-19%]). INTERPRETATION Our findings suggest that low-income mothers with depression and who have newly born children could be effectively helped, even in low-income settings, through multicomponent interventions. Further refinements to this intervention are needed to ensure treatment compliance after the acute phase.
JAMA Pediatrics | 2013
Ricardo Araya; Rosemarie Fritsch; Melissa Spears; Graciela Rojas; Vania Martínez; Sergio Barroilhet; Paul A. Vöhringer; David Gunnell; Paul Stallard; Viviana Guajardo; Jorge Gaete; Sian Noble; Alan A Montgomery
IMPORTANCE Depression can have devastating effects unless prevented or treated early and effectively. Schools offer an excellent opportunity to intervene with adolescents presenting emotional problems. There are very few universal school-based depression interventions conducted in low- and middle-income countries. OBJECTIVE To assess the effectiveness of a school-based, universal psychological intervention to reduce depressive symptoms among adolescents from low-income families. DESIGN, SETTING, AND PARTICIPANTS A 2-arm, parallel, cluster, randomized clinical trial was conducted in secondary schools in deprived socioeconomic areas of Santiago, Chile. Almost all students registered in the selected schools consented to take part in the study. A total of 2512 secondary school students from 22 schools and 66 classes participated. INTERVENTIONS Students in the intervention arm attended 11 one-hour weekly and 2 booster classroom sessions of an intervention based on cognitive-behavioral models. The intervention was delivered by trained nonspecialists. Schools in the control arm received the standard school curriculum. MAIN OUTCOMES AND MEASURES Scores on the self-administered Beck Depression Inventory-II at 3 months (primary) and 12 months (secondary) after completing the intervention. RESULTS There were 1291 participants in the control arm and 1221 in the intervention arm. Primary outcome data were available for 82.1% of the participants. There was no evidence of any clinically important difference in mean depression scores between the groups (adjusted difference in mean, -0.19; 95% CI, -1.22 to 0.84) or for any of the other outcomes 3 months after completion of the intervention. No significant differences were found in any of the outcomes at 12 months. CONCLUSIONS AND RELEVANCE A well-designed and implemented school-based intervention did not reduce depressive symptoms among socioeconomically deprived adolescents in Santiago, Chile. There is growing evidence that universal school interventions may not be sufficiently effective to reduce or prevent depressive symptoms. TRIAL REGISTRATION isrctn.org Identifier: ISRCTN19466209.
Trials | 2011
Ricardo Araya; Alan A Montgomery; Rosemarie Fritsch; David Gunnell; Paul Stallard; Sian Noble; Vania Martínez; Sergio Barroilhet; Paul A. Vöhringer; Viviana Guajardo; Felix Cova; Jorge Gaete; Alejandro Gómez; Graciela Rojas
BackgroundDepression is common and can have devastating effects on the life of adolescents. Psychological interventions are the first-line for treating or preventing depression among adolescents. This proposal aims to evaluate a school-based, universal psychological intervention to reduce depressive symptoms among students aged 13-14 attending municipal state secondary schools in Santiago, Chile.Study designThis is a cluster randomised controlled trial with schools as the main clusters. We compared this intervention with a control group in a study involving 22 schools, 66 classes and approximately 2,600 students. Students in the active schools attended 11 weekly and 3 booster sessions of an intervention based on cognitive-behavioural models. The control schools received their usual but enhanced counselling sessions currently included in their curriculum. Mean depression scores and indicators of levels of functioning were assessed at 3 and 12 months after the completion of the intervention in order to assess the effectiveness of the intervention. Direct and indirect costs were measured in both groups to assess the cost-effectiveness of this intervention.DiscussionAs far as we are aware this is the first cluster randomised controlled trial of a school intervention for depression among adolescents outside the Western world.Trial RegistrationISRCTN19466209
Comparative Biochemistry and Physiology Part C: Pharmacology, Toxicology and Endocrinology | 2000
Myriam Orellana; Ramón Rodrigo; Lilian Thielemann; Viviana Guajardo
In the liver, seven days of bile duct ligation (BDL) decreases the cytochrome P-450 content and the UDP-glucuronyl transferase activity. Also, a decrease in the water soluble antioxidant mechanism reflected in the activities of the enzymes superoxide dismutase (SOD), catalase and the glutathione peroxidase (GTPx) was found in the liver but not in the kidney. Despite an increase in the amount of the GSH in the liver, increased lipid peroxidation is produced in the BDL rats, as indicated by the levels of malondialdehyde (MDA). The kidney responded in a different way to cholestasis, decreasing only the UDP-glucuronyl transferase activity and increasing the levels of GSH and MDA. In the red blood cells the activity of the antioxidant enzymes SOD, GTPx and catalase and the content of GSH were not modulated by cholestasis. In conclusion, disturbance of the oxidant-antioxidant balance might be responsible for cholestatic liver injury and impaired renal function in BDL rats.
Comparative Biochemistry and Physiology C-toxicology & Pharmacology | 2002
Myriam Orellana; Nelson Varela; Viviana Guajardo; Julia Araya; Ramón Rodrigo
Cytochrome P450-dependent oxidation of lauric acid, p-nitrophenol and ethanol by liver microsomal fractions were studied in control rats and in animals given either ethanol, red wine, or alcohol-free red wine for 10 weeks. Ethanol increased the total cytochrome P450 and the isoenzyme 2E1 content, as well as the p-nitrophenol hydroxylation and ethanol oxidation. These effects of ethanol treatment were attenuated by red wine administration. Red wine increased the total antioxidant capacity of plasma, whereas the alcohol-free red wine decreased the cytochrome P450 content and decreased the oxidation of lauric acid, p-nitrophenol and ethanol to values lower than control. It is concluded that red wine administration attenuates the ethanol-induced enhancement in liver microsomal parameters dependent on cytochrome P450 2E1 activity, an affect that seems to be accomplished by the non-alcoholic constituents of red wine known to have antioxidant properties.
Revista Medica De Chile | 2012
Graciela Rojas; Jorge Gaete; Viviana Guajardo; Vania Martínez; Sergio Barroihlet; Juan Meneses; Rosemarie Fritsch; Ricardo Araya
BACKGROUND The presence of emotional problems may trigger drug abuse. AIM To determine the association between illicit drug use and severity of depression symptoms among students of public secondary schools in Santiago, Chile. MATERIAL AND METHODS A probabilistic sample of 2,597 adolescents aged between 12 and 18 years (45% women), attending first year in public high-schools in Santiago, answered self-report questionnaires about consumption, during the last 30 days ,of alcohol, tobacco and marihuana, and the Beck Depression Inventory - II. Logistic regression models were used to study the association between drug use and severity of depression symptoms, adjusting by sex. RESULTS Tobacco and marihuana use was reported by 38 and 13% of students, respectively. Frequency of consumption was significantly higher among women. Mild, moderate or severe depressive symptoms were found among 16%, 14% and 9% of students, respectively. Depressive symptoms were more common among women. There was a significant association between drug use and severity of depression among participants of both genders. CONCLUSIONS The association between depressive symptoms and drug use should be considered on the design of treatment guidelines for these health problems in Chile.
Revista Medica De Chile | 2011
Graciela Rojas; Rosemarie Fritsch; Ariel Castro; Viviana Guajardo; Pamela Torres; Berta Díaz
Background: Chile is receiving immigrant populations coming from other Latin-American countries. Aim: To determine the prevalence of Common Mental Disorders (CMD) among immigrants who live in Independencia, a quarter in Santiago, Chile. Material and Methods: A cross sectional study was carried out in the primary health care clinic and in the state-funded school of Independencia. A representative sample of 282 adults and 341 children were interviewed. Mental disorders were diagnosed using CIS-R and MINI structured interviews. Results: The interviewed immigrants came mostly from Peru. The prevalence of mental disorders in the adult population was 17.8% and among children, it was 29.3%. Conclusions: The adult immigrants have a lower prevalence of mental disorders than the Chilean population but it increases among children. Barriers of access to health services, that should be solved, were detected.
Comparative Biochemistry and Physiology C-toxicology & Pharmacology | 2002
Myriam Orellana; Julia Araya; Viviana Guajardo; Ramón Rodrigo
Cytochrome P450 (CYP)-dependent oxidation of lauric acid, p-nitrophenol and ethanol by microsomal fractions of kidney were studied in control rats and in animals given either ethanol, red wine, or alcohol-free red wine for 10 weeks. Ethanol increased the total CYP content and specifically CYP 2E1, as well as p-nitrophenol and ethanol oxidation. The effects of ethanol treatment on the content and activity of CYP 2E1 were attenuated when red wine was administered, while the alcohol-free red wine values were similar to those of the control group. Although lauric acid hydroxylation was decreased by red wine treatment, the content of CYP 4A1 was not influenced by drinking fluids. We conclude that red wine administration attenuates the ethanol-induced enhancement of microsomal activities dependent on CYP 2E1 of rat kidney. Our results suggest that the non-alcoholic constituents of red wine could account for this modulation.
Comparative Biochemistry and Physiology C-toxicology & Pharmacology | 2001
Myriam Orellana B; Viviana Guajardo; Julia Araya; Lilian Thieleman; Ramón Rodrigo
Parameters of oxidative stress, microsomal cytochrome P450 activity and peroxisomal fatty acid oxidation were studied in liver of rats following acetone (1% v/v) consumption for 7 days. Acetone treatment increased the activity of catalase and decreased the activities of superoxide dismutase (SOD) and glutathione peroxidase (GTPx), but did not significantly modify the liver content of malondialdehyde (MDA) and reduced glutathione. Also, acetone increased the total content of cytochrome P450, the microsomal lauric acid hydroxylation, aminopyrine N-demethylation and the peroxisomal beta-oxidation of palmitoyl CoA. These effects were similar to those found previously in starved and ethanol-treated rats, supporting the hypothesis that ketone bodies would be the common inducer of microsomal and peroxisomal fatty acid oxidation in these metabolic states.
Revista Medica De Chile | 2012
Sergio Barroilhet; Rosemarie Fritsch; Viviana Guajardo; Vania Martínez; Paul A. Vöhringer; Ricardo Araya; Graciela Rojas
BACKGROUND Suicidal behaviors and depression are prevalent phenomena among adolescents, and are considered a public health problem. AIM To determine the prevalence of depressive symptoms and suicidal behaviors and the relationship between both phenomena, in a representative sample of students from ninth grade in Santiago, Chile. MATERIAL AND METHODS We recruited a probability sample of 2,597 adolescents who answered a questionnaire with questions about suicidal behavior and the Beck Depression Inventory (BDI-II). RESULTS The lifetime prevalence of suicidal ideation and planning was 21 and 14%, respectively. The prevalence for the past two weeks was 6.7 and 4.4% for suicidal ideation and planning, respectively. Autolytic behaviors, once in lifetime and in the past week were referred by 26 and 4% of respondents, respectively. In one third of these, self-harm coincided with recent suicide ideation or planning. All levels of suicidal behavior were more frequently reported by women. Clinically significant depressive symptoms were present in 23.5% of adolescents. Females doubled male rates. Severe depressive symptoms were present in 9.4% of the sample. A higher level of suicidal behavior correlated with more severe forms of depression. Sixty percent of adolescents who reported recent self-harm, had clinically relevant depressive symptoms. Two thirds of them had severe symptoms. CONCLUSIONS Suicidal behavior in Chilean adolescents is prevalent, and there is an association between this behavior and the level of depression. The school is a good place to identify and develop preventive measures for teenagers.