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Dive into the research topics where Johannes Lehtonen is active.

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Featured researches published by Johannes Lehtonen.


Journal of Psychosomatic Research | 2000

Depression is strongly associated with alexithymia in the general population.

Kirsi Honkalampi; Jukka Hintikka; Antti Tanskanen; Johannes Lehtonen; Heimo Viinamäki

OBJECTIVE This study examines how alexithymia and depression are related to each other in men and women in a sample of Finnish general population (n = 2018). METHODS Alexithymia was screened using the 20-item version of the Toronto Alexithymia Scale. Level of depression was assessed using the 21-item Beck Depression Inventory (BDI). Life satisfaction was estimated with a structured scale. RESULTS The prevalence of alexithymia was 12.8% in men and 8.2% in women. However, the prevalence of alexithymia was 32.1% among those having BDI scores of > or = 9, but only 4.3% among the nondepressed subjects (p < 0.001). The BDI scores explained 29.2% of the variation in TAS-20 scores. Alexithymia was associated with several sociodemographic factors if depression was not taken into account. However, after including depression in the logistic regression models, only depression and low life satisfaction were associated with alexithymia, both in men and women. CONCLUSION These results suggest that alexithymia has a close relationship to depression in the general population. The impact of social factors on alexithymia may be primarily explained by depression. Depression must be taken into account as a confounding factor when studying alexithymia in general populations due to the strong association between alexithymia and depression.


Psychological Medicine | 2000

Quantitative MRI of the hippocampus and amygdala in severe depression

Esa Mervaala; J. Föhr; M. Könönen; M. Valkonen-Korhonen; P. Vainio; K. Partanen; Juhani Partanen; Jari Tiihonen; Heimo Viinamäki; A.-K. Karjalainen; Johannes Lehtonen

BACKGROUND There is little evidence to support possible structural changes in the amygdala and hippocampus of patients with severe depression. METHODS Quantitative MRI of the amygdala and hippocampus, as well as proton spectroscopy (MRS) of mesial temporal structures were studied in 34 drug-resistant in-patients with major depression and compared with 17 age-matched controls. Volumetric MRI data were normalized for brain size. RESULTS The volume of the left hippocampus was significantly smaller in the patients compared with the controls. Both groups exhibited similar significant hippocampal asymmetry (left smaller than right). The patients, but not the controls, had significant asymmetry of the amygdalar volumes (right smaller than left). No differences were observed between the patients and controls in the T2 relaxation times for the hippocampus and amygdala. Mesial temporal lobe MRS revealed a significantly elevated choline/creatine ratio in the patients compared with the controls. CONCLUSIONS This quantitative MRI study provides support for a possible association between structural and biochemical substrates and severe drug-resistant major depression.


Psychopharmacology | 1999

Striatal dopamine transporter density in major depression.

Teijamari Laasonen-Balk; Jyrki T. Kuikka; Heimo Viinamäki; Minna Husso-Saastamoinen; Johannes Lehtonen; Jari Tiihonen

Rationale: There are no previous data available regarding [123I]β-CIT binding to the dopamine transporter sites in the basal ganglia in depressed patients. Objective: The present study tested the hypothesis that the brain DAT density in depressed patients is lower than that in matched healthy controls. Methods: Fifteen drug-naive outpatients with major depression and 18 healthy controls were investigated using single photon emission computerized tomography (SPECT) with a high-affinity dopamine transporter specific radioligand, 123I-labeled β-CIT (2β-carbomethoxy-3β-(4-iodophenyl)-tropane). Results: We found a significantly higher [123I]β-CIT uptake in both sides of the basal ganglia in patients with major depression than in the controls (Mann-Whitney U-test, P = 0.002 on the right and P = 0.003 on the left). Conclusions: The radioligand uptake reflecting the DAT density was significantly higher among the patients than in the controls. This finding is unexpected, since it is generally believed that monoaminergic neurotransmission is lower in depression, and therefore it could be assumed that a reduction in dopamine transmission would lead to secondary down-regulation of DAT density. However, it is possible that up-regulation of the DAT may be the primary alteration, which leads to lower intrasynaptic dopamine concentration and to lower dopamine neural transmission.


European Journal of Nuclear Medicine and Molecular Imaging | 1997

Single-photon emission tomography imaging of monoamine transporters in impulsive violent behaviour

Jari Tiihonen; Jyrki T. Kuikka; Kim A. Bergström; Jari Karhu; Heimo Viinamäki; Johannes Lehtonen; Tero Hallikainen; Jiwei Yang; Panu Hakola

Abstract.Several studies have shown that impulsive violent and suicidal behaviour is associated with a central serotonin deficit, but until now it has not been possible to use laboratory tests with high sensitivity and specificity to study this kind of deficit or to localize the sites of serotonergic abnormalities in the living human brain. The aim of this study was to test the hypothesis that monoamine transporter density in brain is decreased in subjects with impulsive violent behaviour. We studied serotonin (5-HT) and dopamine (DA) transporter specific binding in 52 subjects (21 impulsive violent offenders, 21 age- and sex-matched healthy controls, and ten non-violent alcoholic controls) with single-photon emission tomography (SPET) using iodine-123-labelled 2β-carbomethoxy-3β(4-iodophenyl)tropane ([123I]β-CIT) as the tracer. The blind quantitative analysis revealed that the 5-HT specific binding of [123I]β-CIT in the midbrain of violent offenders was lower than that in the healthy control subjects (P<0.005; t test) or the non-violent alcoholics (P<0.05). The results imply that habitual impulsive aggressive behaviour in man is associated with a decrease in the 5-HT transporter density.


Sleep | 2001

Nightmares as predictors of suicide

Antti Tanskanen; Jaakko Tuomilehto; Heimo Viinamäki; Erkki Vartiainen; Johannes Lehtonen; Pekka Puska

Nightmares are intensive dreams with negative emotional tone. Frequent nightmares can pose a serious clinical problem and in 2001, Tanskanen et al. found that nightmares increase the risk of suicide. However, the dataset used by these authors included war veterans in whom nightmare frequency - and possibly also suicide risk - is elevated. Therefore, re-examination of the association between nightmares and suicide in these data is warranted. We investigated the relationship between nightmares and suicide both in the general population and war veterans in Finnish National FINRISK Study from the years 1972 to 2012, a dataset overlapping with the one used in the study by Tanskanen et al. Our data comprise 71,068 participants of whom 3139 are war veterans. Participants were followed from their survey participation until the end of 2014 or death. Suicides (N = 398) were identified from the National Causes of Death Register. Frequent nightmares increase the risk of suicide: The result of Tanskanen et al. holds even when war experiences are controlled for. Actually nightmares are not significantly associated with suicides among war veterans. These results support the role of nightmares as an independent risk factor for suicide instead of just being proxy for history of traumatic experiences.


Acta Psychiatrica Scandinavica | 1996

Correlates of life satisfaction among psychiatric patients

Heli Koivumaa-Honkanen; Heimo Viinamäki; Honkanen R; Antti Tanskanen; Risto Antikainen; Leo Niskanen; Juha E. Jääskeläinen; Johannes Lehtonen

The aim of this study was to examine the sociodemographic and clinical variables associated with life satisfaction in psychiatric patients. The study population consisted of out‐patients and in‐patients (n= 1204) treated at the Department of Psychiatry of Kuopio University Hospital in North Savo, Finland, during May 1993. Sociodemographic, psychosocial and clinical correlates of life satisfaction were examined by means of two different questionnaires, one directed at patients and the other directed at the staff. Life satisfaction was assessed by means of a separate scale based on four questions. Patients with schizophrenia were less dissatisfied than patients with other disorders. The strongest correlates of dissatisfaction were depression and poor social support. Other factors relating to dissatisfaction in multiple regression analysis were self‐rated health and poor financial circumstances. A psychosomatic reaction tendency or degree of psychosocial functioning at the time of the study was not independently related to life satisfaction. Psychiatric patients who are dissatisfied should be evaluated both for depression and for effectiveness of their social network.


Psychotherapy and Psychosomatics | 2000

Is Alexithymia a Permanent Feature in Depressed Patients

Kirsi Honkalampi; Jukka Hintikka; Pirjo Saarinen; Johannes Lehtonen; Heimo Viinamäki

Background: A six-month follow-up study was conducted to determine whether alexithymia is a permanent feature in 169 depressed outpatients. Methods: Diagnosis of depression was confirmed by means of the Structured Clinical Interview for DSM-III-R (SCID-I). Alexithymia was screened using the 20-item version of the Toronto Alexithymia Scale (TAS-20) and severity of depression was assessed using the 21-item Beck Depression Inventory (BDI). Results: Almost 40% of the patients were considered alexithymic at baseline, but only 23% at follow-up. Alexithymic patients were more often moderately or severely depressed than other patients in both study phases. The BDI scores explained 23% (at baseline) and 42% (at follow-up) of the variation in TAS-20 scores. The decrease in the TAS-20 scores was associated with a concurrent decrease in BDI scores. Conclusions: Alexithymic patients with depressive disorders do not appear to form a stable group. On the contrary, alexithymia seems to change as a function of depression. In the light of these results, alexithymia appears not to be a stable personality trait among depressed patients, and furthermore, it seems possible that alexithymic features respond to psychiatric treatment.


Social Psychiatry and Psychiatric Epidemiology | 2001

Suicidal ideation in the Finnish general population. A 12-month follow-up study

Jukka Hintikka; T. Pesonen; Pirjo Saarinen; Antti Tanskanen; Johannes Lehtonen; Heimo Viinamäki

Background The epidemiology of suicidal ideation has remained a relatively unstudied area. The aim of this study was to investigate the incidence, prevalence and persistence of and recovery from suicidal ideation in a sample of the Finnish general population. Methods Postal questionnaires including the Beck Depression Inventory (BDI) were mailed to the study subjects (n = 1,593) at baseline and on follow-up after 12 months. The suicidality item of BDI was used to screen suicidal ideation. Results The 12-month incidence (4.6 %) and prevalence of suicidal ideation (14.7 %) were higher in men than in women (3.1 % and 9.2 %, respectively). Sixty-nine per cent of those men and 59 % of those women who had suicidal ideation at baseline continued to have suicidal thoughts on follow-up. Suicidal ideation and the severity of depression associated strongly. Over half of the men and women who had persistent suicidal ideation had not visited any health services for help with psychological distress during the 12-month follow-up period. Daily smoking associated with a decreased probability of recovery from suicidal ideation. Conclusions Suicidal ideation is common and persistent at the population level. Seeking professional help for depression with suicidal tendencies is disproportionately low in relation to the high prevalence of suicidal ideation.


Psychotherapy and Psychosomatics | 2001

Why do alexithymic features appear to be stable? A 12-month follow-up study of a general population

Kirsi Honkalampi; Heli Koivumaa-Honkanen; Antti Tanskanen; Jukka Hintikka; Johannes Lehtonen; Heimo Viinamäki

Background: This 12-month follow-up study investigated the prevalence of alexithymia and its relationship with depression in a sample of the general population from Eastern Finland (n = 1,584). Methods: Alexithymia was assessed using the 20-item version of the Toronto Alexithymia Scale (TAS) and depression using the 21-item Beck Depression Inventory (BDI). Results: The prevalence of alexithymia in each study phase was similar (baseline: 9.7%; follow-up: 10.1%). Mean values of BDI, TAS-20 and subfactors of the TAS-20 also remained unchanged between the study phases. However, by using the original cutoff points, we found that a proportion of the subjects were in a different TAS-20 category on follow-up than at baseline. The mean values of BDI had not changed in those subjects who had similar alexithymia status in both phases, but increased or decreased in parallel with the change in TAS-20 score among all other subjects. Conclusions: Our findings indicate that it is important to use a variety of viewpoints when studying changes in alexithymia status. Alexithymia appears to be a stable trait based on the similarity of the mean TAS-20 scores in separate study phases. However, when focusing on the changes in alexithymia status at the individual level, alexithymic features also appear to be state dependent and strongly related to depressive symptoms.


European Journal of Nuclear Medicine and Molecular Imaging | 1995

Imaging of serotonin and dopamine transporters in the living human brain

Jyrki T. Kuikka; Jari Tiihonen; Kim A. Bergström; Jari Karhu; Päivi Hartikainen; Heimo Viinamäki; Esko Länsimies; Johannes Lehtonen; Panu Hakola

Alterations in brain serotonin (5-HT) and dopamine (DA) activity are associated with several neuropsychiatric disorders, but until now it has not been possible to simultaneously visualize or quantify the 5-HT and the DA transporter density in the living human brain. In this paper we report on the imaging of 5-HT and DA transporters in 28 healthy controls with single-photon emission tomography using iodine-123 labelled 2β-carbomethoxy-3β-(4-iodophenyl)tropane ([123I]β-CIT) as the tracer. The [123I]β-CIT distribution showed the most prominent 5-HT activity in the medial frontal cortex, hypothalamus, midbrain and occipital cortex and the greatest DA activity in the basal ganglia. The specific binding of the 5-HT transporters in the medial frontal cortex was 0.377±0.031 and that of the DA transporters in the basal ganglia, 0.916±0.007. Gjedde-Patlak plots indicated two separate components: the first was assumed to represent 5-HT transporters with a slope of 1.29±0.27 h−1 and the second, DA transporters with a slope of 0.30±0.04 h−1. This distinct kinetic pattern and the fact that 5-HT and DA transporters are situated in different parts of the brain provides an opportunity to study in vivo patients suffering from various neuropsychiatric disorders.

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Heimo Viinamäki

Helsinki University Central Hospital

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Pirjo Saarinen

University of Eastern Finland

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Juhani Partanen

University of Eastern Finland

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Jari Karhu

University of Eastern Finland

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Eila Laukkanen

University of Eastern Finland

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