Pain, functional disability and mental disorders as potential mediators of the association between chronic physical conditions and suicidal ideation in community living older adults.

OBJECTIVES: To examine the associations between chronic physical conditions and suicidal ideation and to assess whether associations are mediated by pain, anxiety, depression, post-traumatic stress syndrome (PTSS), and functional disability. METHODS: The study sample includes 1533 older adults aged 65+ recruited in primary care clinics between 2011-2013 and participating in Quebec's Health Survey on Services "Étude sur la Santé des Aînés-Services" (ESA-S) study. Path analysis was used to assess the associations. The presence of suicidal behaviour was ascertained using 4 questions. PTSS was based on a validated scale for primary care older adults. Anxiety and depression were assessed according to DSM-IV criteria. Pain was self-reported on an ordinal scale and functional disability was based on the presence of disability in 8 dimensions of activities of daily living. The main predictors included a list of 13 physical disorders identified by diagnostic codes. Suicidal ideation was also controlled by a number of socio-demographic and psychosocial factors. RESULTS: PTSS, depression, and functional disability mediate the association between various chronic conditions and suicidal ideation. Although pain and anxiety are associated with many physical disorders, they did not mediate the association with suicidal ideation. CONCLUSIONS: Chronic physical disorders are associated with suicidal ideation, either directly or indirectly through PTSS, depression, and functional disability. The findings underscore the importance of early identification and management of older patients with specific chronic disorders in primary care as they may be most at risk for suicidal ideation.

The association between self-reported daily hassles and cortisol levels in depression and anxiety in community living older adults.

OBJECTIVES: The aim of this study was to assess whether the association, in a naturalistic setting, between daily hassles and diurnal salivary cortisol differs in the presence of depression and anxiety in older adults. METHODS: Data were assessed in a large representative community sample of older adults (n = 1760). A multinomial analysis was used to study as an outcome variable: no disorder, depression only, anxiety only and depression and anxiety, as a function of daily hassles and cortisol levels controlling for age, gender and time of saliva collection. Multivariate regression analyses were also carried out to test the association between daily hassles and cortisol levels stratified by depression and anxiety status. RESULTS: A significant positive association was observed between the number of daily hassles reported and cortisol levels in participants with no depression and no anxiety and in participants with anxiety. Participants without depression and anxiety, and those with depression only, had significant lower cortisol levels later in the day. This was not observed in respondents with anxiety. CONCLUSION: Stressors such as daily hassles are associated with cortisol secretion in depression and anxiety in older adults in a large epidemiologic setting.

Fetal growth restriction and the development of major depression.

OBJECTIVE: To test the association between fetal growth restriction and the lifetime risk of major depression and the number of recurrent episodes. METHOD: Study subjects (n = 1101) were offspring of participants in the Providence, RI, site of the National Collaborative Perinatal Project. Cox regression was used to investigate the relation between measures of birth size and the lifetime risk of depression and the mean number of depressive episodes was compared across categories of birth size. RESULTS: There was no association between low birth weight, gestational age, ponderal index and small for gestational age and the lifetime risk of major depression, or the number of recurrent episodes. CONCLUSION: Fetal growth restriction, as reflected by multiple measures of birth size, is not associated with the risk of a major depression or the subsequent recurrence of depressive episodes. Results of this study do not support a 'fetal programming' effect in depression.

Interaction between dopamine and glutamate receptors following treatment with NMDA receptor antagonists.

Interactions between dopamine and glutamate neurotransmission have been reported to play an important role in a number of different systems. We were interested in examining the effects of sub-chronic treatment with NMDA receptor antagonists (dizocilpine [MK-801], and 3-carboxy-piperazin-propyl phosphonic acid [CPP]) on dopamine D(1)-like, dopamine D(2)-like, as well as glutamate receptors of the NMDA and AMPA receptor subtypes in the neostriatum and substantia nigra of rats that had received a massive dopamine denervation at 3 days of age. Using quantitative ligand binding autoradiography, we demonstrated that the two NMDA receptor antagonists did not have different profiles of action. Furthermore, while we found a significant negative relationship between NMDA receptors and dopamine receptors (both dopamine D(1)-like and D(2)-like receptor subtypes) in the neostriatum, AMPA receptors were positively correlated with dopamine D(1)-like binding sites in all regions investigated. These findings suggest that the interrelationship between dopamine and glutamate receptors is highly controlled and that the nigrostriatal dopamine systems play an important role in this interaction.