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Dive into the research topics where Sami Leppämäki is active.

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Featured researches published by Sami Leppämäki.


BMC Psychiatry | 2003

The Mood Disorder Questionnaire improves recognition of bipolar disorder in psychiatric care

Erkki Isometsä; Kirsi Suominen; Outi Mantere; Hanna Valtonen; Sami Leppämäki; Marita Pippingsköld; Petri Arvilommi

BackgroundWe investigated our translation of The Mood Disorder Questionnaire (MDQ) as a screening instrument for bipolar disorder in a psychiatric setting in Finland.MethodsIn a pilot study for the Jorvi Bipolar Study (JoBS), 109 consecutive non-schizophrenic psychiatric out- and inpatients in Espoo, Finland, were screened for bipolar disorder using the Finnish translation of the MDQ, and 38 of them diagnostically interviewed with the SCID.ResultsForty subjects (37%) were positive in the MDQ screen. In the SCID interview, twenty patients were found to suffer from bipolar disorder, of whom seven (70%) of ten patients with bipolar I but only two (20%) of ten with bipolar II disorder had been previously clinically correctly diagnosed. The translated MDQ was found internally consistent (alpha 0.79) and a feasible screening tool.ConclusionsBipolar disorder, particularly type II, remains commonly unrecognized in psychiatric settings. The Mood Disorder Questionnaire is a feasible screen for bipolar disorder, which could well be integrated into psychiatric routine practice.


Bipolar Disorders | 2008

Differences in incidence of suicide attempts during phases of bipolar I and II disorders.

Hanna Valtonen; Kirsi Suominen; Jari Haukka; Outi Mantere; Sami Leppämäki; Petri Arvilommi; Erkki Isometsä

BACKGROUND Differences in the incidence of suicide attempts during various phases of bipolar disorder (BD), or the relative importance of static versus time-varying risk factors for overall risk for suicide attempts, are unknown. METHODS We investigated the incidence of suicide attempts in different phases of BD as a part of the Jorvi Bipolar Study (JoBS), a naturalistic, prospective, 18-month study representing psychiatric in- and outpatients with DSM-IV BD in three Finnish cities. Life charts were used to classify time spent in follow-up in the different phases of illness among the 81 BD I and 95 BD II patients. RESULTS Compared to the other phases of the illness, the incidence of suicide attempts was 37-fold higher [95% confidence interval (CI) for relative risk (RR): 11.8-120.3] during combined mixed and depressive mixed states, and 18-fold higher (95% CI: 6.5-50.8) during major depressive phases. In Coxs proportional hazards regression models, combined mixed (mixed or depressive mixed) or major depressive phases and prior suicide attempts independently predicted suicide attempts. No other factor significantly modified the risks related to these time-varying risk factors; their population-attributable fraction was 86%. CONCLUSIONS The incidence of suicide attempts varies remarkably between illness phases, with mixed and depressive phases involving the highest risk by time. Time spent in high-risk illness phases is likely the major determinant of overall risk for suicide attempts among BD patients. Studies of suicidal behavior should investigate the role of both static and time-varying risk factors in overall risk; clinically, management of mixed and depressive phases may be crucial in reducing risk.


Bipolar Disorders | 2008

Differences in outcome of DSM-IV bipolar I and II disorders.

Outi Mantere; Kirsi Suominen; Hanna Valtonen; Petri Arvilommi; Sami Leppämäki; Tarja Melartin; Erkki Isometsä

OBJECTIVES To investigate whether the course of bipolar disorder (BD) type II is more depressive than that of BD I, and, if so, to explore the underlying factors that cause this difference. METHODS In a prospective, naturalistic study of 191 secondary care psychiatric in- and outpatients diagnosed in an acute phase of BD I or II, 160 patients (85.1%) were followed for 18 months. Using a life chart, the exact timing of symptom states in follow-up was examined. Differences between BD I (n = 75) and II (n = 85) in duration of index phase and episode, time to full remission and recurrence, and time in any mood episode were investigated. RESULTS Patients with BD II spent a higher proportion of time ill (47.5% versus 37.7%; p = 0.02) and in depressive symptom states (58.0% versus 41.7%; p = 0.003) than BD I patients. This was a result of the higher proportion (61.7% versus 48.6%; p = 0.03) and mean number (1.69 versus 1.11; p = 0.006) of depressive illness phases in BD II, rather than of differences in the duration of depressive phases. Type of index phase strongly predicted the outcome. In linear regression models, both BD II and type of index phase predicted more time spent in depressive symptom states. CONCLUSIONS In medium-term follow-up, BD II patients spend about 40% more time in depressive symptom states than BD I patients because a higher proportion of BD II patients have depressive phases and the frequency of these is higher. Differences in type of index phase may markedly confound differences in outcome between BD I and II.


Psychological Medicine | 1998

Randomized trial of physical exercise alone or combined with bright light on mood and health-related quality of life

Timo Partonen; Sami Leppämäki; J. Hurme; Jouko Lönnqvist

BACKGROUND So-called atypical depressive symptoms (carbohydrate craving, prolonged sleep, weight gain, increased appetite) frequently emerge in association with low illumination to which people are ordinarily exposed indoors, or even outdoors at extreme latitudes in wintertime. Our objective was to analyse the effect of physical exercise alone or combined with bright light on mood and the health-related quality of life during winter. METHODS We carried out a randomized controlled trial on 120 indoor employees in southern Finland between November and January. The subjects were allocated to supervised fitness training under bright (2500-4000 lx) or ordinary (400-600 lx) light conditions in a gym 2-3 times weekly for 8 weeks, or supervised relaxation training once a week over the same period as active placebo. We collected questionnaire data on the changes in mood and health-related quality of life after 4 and 8 weeks of training, and after 4 months follow-up. RESULTS Fitness training in bright light resulted in greater relief from atypical depressive symptoms and more vitality than in ordinary room light. Compared with relaxation alone, the former regime improved general mental health and social functioning in addition to the improvement in depressive symptoms and vitality, whereas the latter only increased vitality. CONCLUSIONS Supervised physical exercise combined with exposure to bright light appears to be an effective intervention for improving mood and certain aspects of the health-related quality of life in wintertime. This effect appears unrelated to the history of season-dependent symptoms, being noticeable among healthy individuals.


Journal of Affective Disorders | 2002

Bright-light exposure combined with physical exercise elevates mood.

Sami Leppämäki; Timo Partonen; Jouko Lönnqvist

BACKGROUND Physical exercise alleviates depressive symptoms, as does exposure to bright light, especially in those with seasonal variation. Our objective was to compare the effect of exercise alone or combined with morning bright light on mood and the health-related quality of life in healthy subjects. METHODS Study subjects were working-age adults, randomized in two groups (n=80): exercise in bright light (group A), or exercise in normal indoor illumination (group B). Intervention lasted for 8 weeks and questionnaire data on mood and the health-related quality of life were collected at study entry, and at weeks 4 and 8. RESULTS Physical exercise both in normal indoor illumination and in bright light was effective at alleviating depressive symptoms. The exercise was significantly more effective at alleviating so-called atypical depressive symptoms when combined with bright-light exposure. LIMITATIONS There was no active placebo condition, but a comparative, randomized trial was executed. CONCLUSIONS Physical exercise in bright light had a positive effect on mood and health-related quality of life in a sample of healthy, working-age people. Further research is needed to explore the mechanisms of the apparent additive effect of exercise and light.


European Neuropsychopharmacology | 2003

Effect of controlled-release melatonin on sleep quality, mood, and quality of life in subjects with seasonal or weather-associated changes in mood and behaviour

Sami Leppämäki; Timo Partonen; Olli Vakkuri; Jouko Lönnqvist; Markku Partinen; Moshe Laudon

This study aimed to explore the effects of melatonin on sleep, waking up and well being in subjects with varying degrees of seasonal or weather-associated changes in mood and behaviour. Fifty-eight healthy adults exhibiting subsyndromal seasonal affective disorder (s-SAD) and/or the negative or positive type of weather-associated syndrome (WAS) were randomised to either 2 mg of sustained-release melatonin or placebo tablets 1-2 h before a desired bedtime for 3 weeks. Outcome measures were changes from baseline in sleep quality, sleepiness after waking, atypical depressive symptoms and health-related quality of life by week three. Early morning salivary melatonin concentrations were measured at baseline and treatment cessation in all subjects. Melatonin administration significantly improved the quality of sleep (P=0.03) and vitality (P=0.02) in the subjects with s-SAD, but attenuated the improvement of atypical symptoms and physical parameters of quality of life compared to placebo in the subjects with WAS, positive type.


Neuroscience Letters | 2006

Transition to daylight saving time reduces sleep duration plus sleep efficiency of the deprived sleep

Tuuli Lahti; Sami Leppämäki; Jouko Lönnqvist; Timo Partonen

Daylight saving time (DST) is widely adopted. We explored the effects of transition to daylight saving time on sleep. With the use of wrist-worn accelerometers, we monitored the rest-activity cycles on a sample of 10 healthy adults for 10 days around the transition to summer time. Identical measurement protocols were carried out twice on the same individuals during the transitions in the years of 2003 and 2004, yielding data on 200 person-days for analysis. Both sleep duration and sleep efficiency were reduced after the transition both years. After the transition sleep time was shortened by 60.14min (P<0.01) and sleep efficiency was reduced by 10% (P<0.01) on average. Transition to daylight saving time appears to compromise the process of sleep by decreasing both sleep duration and sleep efficiency.


Acta Psychiatrica Scandinavica | 2009

Gender differences in bipolar disorder type I and II

Kirsi Suominen; Outi Mantere; Hanna Valtonen; Petri Arvilommi; Sami Leppämäki; Erkki Isometsä

Objective:  We investigated gender differences in bipolar disorder (BD) type I and II in a representative cohort of secondary care psychiatric in‐ and out‐patients.


Journal of Circadian Rhythms | 2006

Transition into daylight saving time influences the fragmentation of the rest-activity cycle

Tuuli Lahti; Sami Leppämäki; Sanna-Maria Ojanen; Jari Haukka; Annamari Tuulio-Henriksson; Jouko Lönnqvist; Timo Partonen

Background Daylight saving time is widely adopted. Little is known about its influence on the daily rest-activity cycles. We decided to explore the effects of transition into daylight saving time on the circadian rhythm of activity. Methods We monitored the rest-activity cycles with the use of wrist-worn accelerometer on a sample of ten healthy adults for ten days around the transition into summer time. Identical protocols were carried out on the same individuals in two consecutive years, yielding data on 200 person-days for analysis in this study. Results There was no significant effect on the rest-activity cycle in the sample as a whole. Fragmentation of the rest-activity cycle was enhanced in a subgroup of persons having sleep for eight hours or less (P = 0.04) but reduced in those who preferred to sleep for more than eight hours per night (P = 0.05). The average level of motor activity was increased in persons having the morning preference for daily activity patterns (P = 0.01). Conclusion Transition into daylight saving time may have a disruptive effect on the rest-activity cycle in those healthy adults who are short-sleepers or more of the evening type.


Human Brain Mapping | 2016

Reorganization of functionally connected brain subnetworks in high-functioning autism

Enrico Glerean; Raj Kumar Pan; Juha Salmi; Juha M. Lahnakoski; Ulrika Roine; Lauri Nummenmaa; Sami Leppämäki; Taina Nieminen-von Wendt; Pekka Tani; Jari Saramäki; Mikko Sams; Iiro P. Jääskeläinen

Previous functional connectivity studies have found both hypo‐ and hyper‐connectivity in brains of individuals having autism spectrum disorder (ASD). Here we studied abnormalities in functional brain subnetworks in high‐functioning individuals with ASD during free viewing of a movie containing social cues and interactions. Twenty‐six subjects (13 with ASD) watched a 68‐min movie during functional magnetic resonance imaging. For each subject, we computed Pearsons correlation between haemodynamic time‐courses of each pair of 6‐mm isotropic voxels. From the whole‐brain functional networks, we derived individual and group‐level subnetworks using graph theory. Scaled inclusivity was then calculated between all subject pairs to estimate intersubject similarity of connectivity structure of each subnetwork. Additional 54 individuals (27 with ASD) from the ABIDE resting‐state database were included to test the reproducibility of the results. Between‐group differences were observed in the composition of default‐mode and ventro‐temporal‐limbic (VTL) subnetworks. The VTL subnetwork included amygdala, striatum, thalamus, parahippocampal, fusiform, and inferior temporal gyri. Further, VTL subnetwork similarity between subject pairs correlated significantly with similarity of symptom gravity measured with autism quotient. This correlation was observed also within the controls, and in the reproducibility dataset with ADI‐R and ADOS scores. Our results highlight how the reorganization of functional subnetworks in individuals with ASD clarifies the mixture of hypo‐ and hyper‐connectivity findings. Importantly, only the functional organization of the VTL subnetwork emerges as a marker of inter‐individual similarities that co‐vary with behavioral measures across all participants. These findings suggest a pivotal role of ventro‐temporal and limbic systems in autism. Hum Brain Mapp 37:1066–1079, 2016.

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Kirsi Suominen

Helsinki University Central Hospital

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Hanna Valtonen

Helsinki University Central Hospital

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Petri Arvilommi

Helsinki University Central Hospital

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Timo Partonen

National Institute for Health and Welfare

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Jouko Lönnqvist

National Institute for Health and Welfare

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Pekka Tani

Helsinki University Central Hospital

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