PubMed Health⌕ Search

Biomedical subjects

M Marcelis

Publications and source records attributed to M Marcelis.

10 recordsLinked to original sources
PubMed2004

Abnormal response to metabolic stress in schizophrenia: marker of vulnerability or acquired sensitization?

BACKGROUND: Previous work suggests that individuals with schizophrenia display an altered homovanillic acid (HVA) response to metabolic stress. The present study replicated and extended this paradigm, including individuals with elevated genetic risk for schizophrenia. METHOD: Patients with psychosis (n = 50), non-psychotic first-degree relatives of patients with psychosis (n = 51) and controls without psychosis (n = 50) underwent, in randomized order, double-blind administration of placebo and the glucose analogue 2-deoxy-D-glucose (2DG), which induces a mild, transient clinical state of glucoprivation. Plasma HVA and cortisol were assessed twice before the start of the 2DG/placebo infusion (baseline values), as well as four times post infusion. Data were analysed using multi-level random regression techniques. RESULTS: During the stress condition, significant increases in plasma HVA and cortisol were found. The increase in plasma HVA level during the stress condition was significantly stronger in patients than in controls, whereas this was not the case in relatives v. controls. The increase in plasma cortisol during the stress condition was significantly less in patients than controls, but no significant difference in the increase of plasma cortisol during stress was found in the comparison between relatives and controls. CONCLUSIONS: Patients with psychosis, but not their non-psychotic first-degree relatives, show an altered neurobiological response to metabolic stress, suggesting that this dysregulation is not a genetically transmitted vulnerability, but an illness-related effect, possibly reflecting acquired sensitization of neuroendocrine systems by repeated environmental stressors or repeated stimulation with agonistic drugs.

Adolescent↗
PubMed2003

Cerebral tissue alterations and daily life stress experience in psychosis.

OBJECTIVE: To examine whether the total volumes of cerebrospinal fluid (CSF), cerebral grey matter and white matter were correlated with the experience of environmental stress in daily life situations. METHOD: Twenty-seven patients with psychosis underwent magnetic resonance imaging scanning and a random time-sampling self-assessment technique (Experience Sampling Method) to determine subjective daily life stress experiences. Total cerebral tissue volumes were derived from an automated segmentation procedure. RESULTS: CSF volume was positively associated with daily life event-related stress (beta=0.016, P=0.002), while the association with total white matter was negative (beta=-0.013, P=0.005). The effects were independent of each other and of total cerebral volume and other confounders. No large or significant association was found with grey matter volume. CONCLUSION: Subjective stress experience in daily life is associated with increased CSF and reduced white matter volumes in patients with psychosis, suggesting functional significance of these cerebral measures.

Adolescent↗
PubMed2001

Single or multiple familial cognitive risk factors in schizophrenia?

The fact that relatives of patients with schizophrenia display subtle cognitive abnormalities suggests genetic transmission of an underlying cognitive endophenotype. It was examined to what extent the cognitive abnormalities that discriminate patients and relatives from controls do so independently of each other, and independent of IQ. Neuropsychological measures were assessed in 50 patients with schizophrenia, 50 first-degree relatives of patients with schizophrenia, and 50 healthy controls. The assessment focused on episodic memory, attentional span, simple and complex speed of information, and semantic memory. Factor analysis of the cognitive test results yielded four factors reflecting speed, episodic memory, working memory, and semantic fluency. Performance of the relatives was intermediate to that of the patients and the controls after adjustment for age, sex, educational level, and IQ. For both patients and relatives, speed of information processing, working memory, and episodic memory independently discriminated from control performance, with a similar pattern in the order of the size of the effects. The results suggest the existence of more than one familial cognitive risk factor for schizophrenia. Independent familial cognitive risk factors may represent separate causal influences or separate indicators of risk related to the same genetic mechanism.

Adult↗
PubMed1999

Urbanization and risk for schizophrenia: does the effect operate before or around the time of illness onset?

BACKGROUND: Higher level of urbanicity of place of birth and of place of residence at the time of illness onset has been shown to increase the risk for adult schizophrenia. However, because urban birth and urban residence are strongly correlated, no conclusions can be drawn about the timing of the risk-increasing effect. The current study discriminated between any effect of urbanization before and around the time of illness onset. METHODS: All individuals born between 1972 and 1978 were followed up through the Dutch National Psychiatric Case Register for first admission for schizophrenia until 1995 (maximum age 23 years). Exposure status was defined by a combination of place of birth and place of residence at the time of illness onset in the three most densely populated provinces of the Netherlands (the 'Randstad', exposed) or in all other areas (the 'non-Randstad', non-exposed). The risk for schizophrenia was examined in four different exposure groups: non-exposed born and non-exposed resident (NbNr, reference category), non-exposed born and exposed resident (NbEr), exposed born and non-exposed resident (EbNr) and exposed born and exposed resident (EbEr). RESULTS: The greatest risk for schizophrenia was found in the EbNR group, without evidence for any additive effect of urban residence (rate ratio (RR) for narrow schizophrenia in EbNr group, 2.05 (95 % CI 1.18-3-57); in EbEr group, 1.96 (95% CI, 1.55-2.46)). Individuals who were not exposed at birth, but became so later in life, were not at increased risk of developing schizophrenia (RR for narrow schizophrenia in NbEr group, 0.79 (0.46-1.36)). CONCLUSION: The results suggest that environmental factors associated with urbanization increase the risk for schizophrenia before rather than around the time of illness onset.

Adolescent↗
PubMed1998

The ecogenetics of schizophrenia: a review.

Schizophrenia is generally thought to arise as a result of interactions between genetic vulnerability and environmental risk factors. However, research methods to actually investigate the pattern of hypothesized interactions have only recently been developed. In this article, we review the evidence that genes increase the risk for schizophrenia by making individuals more sensitive to environmental risk factors (genotype-environment interaction), or by making individuals more likely to select high-risk environments (genotype-environment correlation). It is likely that at least some of the impact of genes on the occurrence of schizophrenia is mediated through (sensitivity for) environmental risk factors such as a dysfunctional early family rearing environment, cannabis, viral infections, complications of birth and pregnancy, stressful life events and unknown environmental risk factors associated with urban birth or residence and membership of certain ethnic groups. With the advent of molecular genetics, further knowledge about possible genotype-environment interactions is urgently required in order to develop and improve strategies for the prevention and early treatment of schizophrenia.

Disease Susceptibility↗
PubMed1998

Obstetric complications and familial morbid risk of psychiatric disorders.

Obstetric complications (OCs) have been found to occur in higher frequency in patients with schizophrenia. One explanation for this finding is that the genes that contribute to the schizophrenia phenotype also influence the likelihood to experience OCs. If this were true, morbid risk of psychiatric illness should be higher in the first-degree relatives of both schizophrenic and control probands exposed to OCs, compared to probands not exposed to OCs. We set out to test this hypothesis. Information on OCs, blind to family history of psychiatric disorder, was collected retrospectively through maternal interview in 151 psychotic patients and 100 controls. Family history (FH) in relatives of cases (n = 600) and controls (n = 461) was assessed with the FH-RDC and through personal interviews. Tests for associations between family history and OCs were conducted using Cox proportional hazard regression. In the cases, familial morbid risk of affective disorder was greater in those with a history of OCs (hazard ratio (HR) = 1.9, P = 0.007). Analyses examining individual complications revealed associations between FH of affective disorder and pre-eclampsia (HR = 2.9, P = 0.003) and FH of affective disorder and breech presentation (HR = 2.8, P = 0.02), especially when family history in the relatives was confined to affective illness in the mother (HR pre-eclampsia = 4.4, P = 0.009; HR breech-presentation = 4.2, P = 0.008). In controls, affective illness in the mother was not only associated with breech presentation (HR = 7.0, P = 0.01) and pre-eclampsia (HR = 4.4, P = 0.03) but also with other complications. Familial morbid risk of schizophrenia and related psychoses was not associated with OCs. The positive associations between OCs and familial morbid risk of affective disorder suggest that the factors that contribute to familial aggregation of affective symptoms in psychotic patients also influence the likelihood to experience OCs. Although the proportion of OCs that could be attributed to these factors was very small, part of the relationship between family history of affective disorder and psychosis may be mediated by OCs.

Age of Onset↗
PubMed1998

Urbanization and psychosis: a study of 1942-1978 birth cohorts in The Netherlands.

BACKGROUND: Urban birth is associated with later schizophrenia. This study examined whether this finding is diagnosis-specific and which individuals are most at risk. METHODS: All live births recorded between 1942 and 1978 in any of the 646 Dutch municipalities were followed-up through the National Psychiatric Case Register for first psychiatric admission for psychosis between 1970 and 1992 (N = 42115). RESULTS: Urban birth was linearly associated with later schizophrenia (incidence rate ratio linear trend (IRR), 1.39; 95% confidence interval (95% CI), 1.36-1.42), affective psychosis (IRR, 1.18; 95% CI, 1.15-1.21) and other psychosis (IRR, 1.27; 95% CI, 1.24-1.30). Individuals born in the highest category of the three-level urban exposure were around twice as likely to develop schizophrenia. Associations were stronger for men and for individuals with early age of onset. The effect of urban birth was also stronger in the more recent birth cohorts. CONCLUSIONS: There are quantitative differences between diagnostic categories in the strength of the association between urban birth and later psychiatric disorder. High rates of psychosis in urban areas may be the result of environmental factors associated with urbanization, the effect of which appears to be increasing over successive generations.

Adult↗
PubMed1997

Psychopathological syndromes and familial morbid risk of psychosis.

BACKGROUND: Familial liability in the functional psychoses had traditionally been examined by comparing mutually exclusive diagnostic categories. This study examines overlapping psychopathological dimensions in relation to familial morbid risk of psychosis. METHOD: We tested for associations between seven factor-analysis derived psychopathological dimensions and familial morbid risk of psychosis, in a sample of 150 patients with recent-onset functional psychosis and 548 of their first-degree relatives. RESULTS: A syndrome characterised by affective blunting and insidious and early onset of illness, non-specifically predicted psychosis in the first-degree relatives, whereas a manic syndrome specifically predicted affective psychosis in the relatives. No other main effects were observed, but there were interactions with proband diagnosis: a syndrome characterised by bizarre behaviour, inappropriate affect, catatonia and poor rapport predicted psychosis in relatives of schizophrenic probands, and a syndrome of depressive: symptoms predicted psychosis in relatives of schizoaffective probands. Positive symptoms were not associated with illness in the relatives. CONCLUSIONS: Genetic effects in the functional psychoses may comprise non-specific components that canalise a general, early-onset, affective blunting phenotype and several other, more specific, influences on phenotypic variation.

Adult↗
PubMedDate not supplied

High expressed emotion: marker for a caring family?

"Expressed emotion" (EE) is considered a marker of dysfunctional family interaction in patients with schizophrenia. An alternative hypothesis, however, is that at least some of the different elements of EE really represent attempts on the part of carers to cope with and care for a relative with a psychiatric disorder. EE (criticism and emotional overinvolvement) was measured in relatives (n = 31) of patients with psychotic illness using the Five-Minute Speech Sample (FMSS). Level of EE was examined in relation to (1) patient-reported family involvement in care over the previous 2 years as indicated by medication monitoring, involvement in treatment decisions, and providing a substitute for institutional care; and (2) symptom severity and number of psychotic episodes. Presence of EE in the relative was strongly associated with the degree of family involvement in care (odds ratio [OR] over three levels: 3.2; 95% confidence interval [CI], 1.1 to 9.0). In addition, presence of high EE was associated with number of psychotic episodes in the previous 5 years in the proband (OR over 0, 1, or 2 episodes: 6.2; 95% CI, 1.2 to 31.9). The association with family involvement was confined to emotional overinvolvement (OR = 9.1; 95% CI, 2.0 to 42.2), whereas the association with previous psychotic episodes was confined to criticism (OR = 20.6; 95% CI, 2.8 to 149.3). Emotional overinvolvement may be a state marker for attempts on the part of relatives to be partners in the care for patients with psychotic illness. High level of criticism may be a trait marker in relatives associated with poor prognosis, but could also develop in reaction to a frequently relapsing illness.

Caregivers↗