What are the causes of late-life depression?

Why is depression more common among women than among men?

Women are about twice as likely as are men to develop depression during their lifetime. This Series paper summarises evidence regarding the epidemiology on gender differences in prevalence, incidence, and course of depression, and factors possibly explaining the gender gap. Gender-related subtypes of depression are suggested to exist, of which the developmental subtype has the strongest potential to contribute to the gender gap. Limited evidence exists for risk factors to be specifically linked to depression. Future research could profit from a transdiagnostic perspective, permitting the differentiation of specific susceptibilities from those predicting general psychopathologies within and across the internalising and externalising spectra. An integration of the Research Domain Criteria framework will allow examination of gender differences in core psychological functions, within the context of developmental transitions and environmental settings. Monitoring of changing socioeconomic and cultural trends in factors contributing to the gender gap will be important, as well as the influence of these trends on changes in symptom expression across psychopathologies in men and women.

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Zusammenfassung. Depressionen, leichte kognitive Störungen und Demenzen sind besonders bei älteren Menschen häufig assoziiert. Ähnliche neuropathologische Mechanismen scheinen diesen Zusammenhang und die gegenseitigen Einflüsse mindestens teilweise zu erklären. Wir schlagen hier eine Kurzreview der Rolle der Depression als Risikofaktor, Prodrom oder Folge der kognitiven Störungen vor und skizzieren kurz mögliche Behandlungsansätze.

Vascular depression consensus report - a critical update

BACKGROUND

Vascular depression is regarded as a subtype of late-life depression characterized by a distinct clinical presentation and an association with cerebrovascular damage. Although the term is commonly used in research settings, widely accepted diagnostic criteria are lacking and vascular depression is absent from formal psychiatric manuals such as the Diagnostic and Statistical Manual of Mental Disorders, 5^th edition - a fact that limits its use in clinical settings. Magnetic resonance imaging (MRI) techniques, showing a variety of cerebrovascular lesions, including extensive white matter hyperintensities, subcortical microvascular lesions, lacunes, and microinfarcts, in patients with late life depression, led to the introduction of the term "MRI-defined vascular depression".

DISCUSSION

This diagnosis, based on clinical and MRI findings, suggests that vascular lesions lead to depression by disruption of frontal-subcortical-limbic networks involved in mood regulation. However, despite multiple MRI approaches to shed light on the spatiotemporal structural changes associated with late life depression, the causal relationship between brain changes, related lesions, and late life depression remains controversial. While postmortem studies of elderly persons who died from suicide revealed lacunes, small vessel, and Alzheimer-related pathologies, recent autopsy data challenged the role of these lesions in the pathogenesis of vascular depression. Current data propose that the vascular depression connotation should be reserved for depressed older patients with vascular pathology and evident cerebral involvement. Based on current knowledge, the correlations between intra vitam neuroimaging findings and their postmortem validity as well as the role of peripheral markers of vascular disease in late life depression are discussed.

CONCLUSION

The multifold pathogenesis of vascular depression as a possible subtype of late life depression needs further elucidation. There is a need for correlative clinical, intra vitam structural and functional MRI as well as postmortem MRI and neuropathological studies in order to confirm the relationship between clinical symptomatology and changes in specific brain regions related to depression. To elucidate the causal relationship between regional vascular brain changes and vascular depression, animal models could be helpful. Current treatment options include a combination of vasoactive drugs and antidepressants, but the outcomes are still unsatisfying.

The impact of depressive symptoms on utilization of home care by the elderly: Longitudinal results from the AgeMooDe study

BACKGROUND

Depression is the most common psychiatric disease in older people, often accompanied by co-morbidities and functional limitations. In cross-sectional studies, depression is associated with an increased use of health care resources, including informal care and home care. Longitudinal data are needed to better understand the causal links between depression, functional impairments, and health care utilization.

METHODS

Data were obtained at baseline and follow-up of the multicenter, prospective cohort study "Late life depression in primary care: needs, health care utilization and costs" (AgeMooDe). A sample of 955 primary care patients aged 75 years and older was interviewed twice. The primary outcomes were the average respective amounts of time spent utilizing home care, professional nursing care, domestic help and informal care. These outcomes were analyzed with Generalized Linear Mixed Models (GLMM).

RESULTS

GLMM analysis revealed that the amount of time utilizing home care over the study period was positively associated with depression, higher age, and functional and cognitive impairments, but negatively associated with living alone. In-depth analyses revealed that these associations were particularly obvious for the utilization of informal care.

LIMITATIONS

The generalizability of our findings may be limited due to use of a dimensional instrument to determine depressive symptoms.

CONCLUSIONS

Over the study period, the average amount of time receiving home care and especially informal care increased in the group of patients with depression only. People with depressive symptoms experience a growing number of functional limitations over time, increasing their dependency on others. Functional limitations, depression and dependency appear to form a vicious cycle.

Membrane lipid rafts and neurobiology: age-related changes in membrane lipids and loss of neuronal function

A better understanding of the cellular physiological role that plasma membrane lipids, fatty acids and sterols play in various cellular systems may yield more insight into how cellular and whole organ function is altered during the ageing process. Membrane lipid rafts (MLRs) within the plasma membrane of most cells serve as key organizers of intracellular signalling and tethering points of cytoskeletal components. MLRs are plasmalemmal microdomains enriched in sphingolipids, cholesterol and scaffolding proteins; they serve as a platform for signal transduction, cytoskeletal organization and vesicular trafficking. Within MLRs are the scaffolding and cholesterol binding proteins named caveolin (Cav). Cavs not only organize a multitude of receptors including neurotransmitter receptors (NMDA and AMPA receptors), signalling proteins that regulate the production of cAMP (G protein-coupled receptors, adenylyl cyclases, phosphodiesterases (PDEs)), and receptor tyrosine kinases involved in growth (Trk), but also interact with components that modulate actin and tubulin cytoskeletal dynamics (e.g. RhoGTPases and actin binding proteins). MLRs are essential for the regulation of the physiology of organs such as the brain, and age-related loss of cholesterol from the plasma membrane leads to loss of MLRs, decreased presynaptic vesicle fusion, and changes in neurotransmitter release, all of which contribute to different forms of neurodegeneration. Thus, MLRs provide an active membrane domain that tethers and reorganizes the cytoskeletal machinery necessary for membrane and cellular repair, and genetic interventions that restore MLRs to normal cellular levels may be exploited as potential therapeutic means to reverse the ageing and neurodegenerative processes.

Subclinical Mood and Cognition Impairments and Blood Pressure Control in a Large Cohort of Elderly Hypertensives

BACKGROUND

Blood pressure (BP) control in the elderly is often limited by poor compliance with prescribed regimen. Both can be influenced by clinical cognitive or mood impairments; however, the impact of subclinical alterations of cognition or mood remains unknown.

OBJECTIVES

To assess the relation between cognition, mood, and BP control in treated older hypertensive patients.

DESIGN

Cross-sectional association study.

SETTING

Predefined substudy to the POLFOKUS nationwide survey investigating the correlates of poor BP control in patients randomly drawn from primary and specialist practices across Poland.

PARTICIPANTS

1988 outpatients ≥65 years of age treated for hypertension for at least 1 year.

MEASUREMENTS

BP was mean of at least 2 office measurements. We assessed adherence to antihypertensive medications using a questionnaire and performed screening tests for cognitive deficits [Abbreviated Mental Test Score (AMTS)] and mood disorders [Geriatric Depression Scale (GDS)]. In all patients, we used a unified (BP <140/90 mm Hg) and in ≥80 years old a unified or age-specific (<150 mm Hg systolic BP) definition of BP control. We fitted logistic regression models to assess the probability of poor BP control in association with cognitive and mood disturbances.

RESULTS

The mean [standard deviation (SD)] age of 1988 (65.6% women) patients was 73.9 (6.0) years (19.3% ≥80 years old). Cognitive and mood impairments were observed in 8.0% and 37.2%, respectively. Mean systolic and diastolic BP were 141.8 (16.4) and 83.6 (9.5) mm Hg, respectively. According to age-stratified and unified definition of proper BP control, goal BP was achieved in 65.4% and 38.5% patients ≥80 years of age, respectively. In younger patients, the control reached 46%. Globally, 66% patients adhered to antihypertensive medications. Poor compliance was related to cognitive and mood impairments. When unified goal was applied, there was a 15.0% higher risk of finding poor BP control per 1 score lost in AMTS and an 8.0% increase per 1 score gained in GDS (all P < .001).

CONCLUSION

Poorer BP control is related to subclinical worsening of cognition and mood, which supports widespread use of the Comprehensive Geriatric Assessment even in apparently self-dependent older patients with hypertension.

Objective drivers of subjective well-being in geriatric inpatients: mobility function and level of education are general predictors of self-evaluated health, feeling of loneliness, and severity of depression symptoms

Purpose

Identification of optimal predictors for different indicators of subjective well-being (SWB) in geriatric inpatients: (1) self-evaluated health status (SEH), (2) feeling of loneliness (FoL), and (3) severity of depression symptoms (SoDS). Investigation of the relationship between response categories of the SWB indicators and their predictors.

Methods

The data were collected retrospectively from hospital records. All 555 geriatric inpatients underwent a comprehensive geriatric assessment, including the Timed Up and Go (TUG) test. The Bayesian information criterion was applied in ordinal logistic regression models to identify optimal predictors of SEH, FoL, and SoDS among different objective factors.

Results

After controlling for high-stress situations in the recent past, motor slowness measured with the TUG test, and a level of education were jointly selected as the best predictors of all three SWB indicators. The speed of performing the TUG test improved SEH (OR = 2.08) and decreased both FoL (OR = 0.41) and SoDS (OR = 0.41). A higher level of education improved SEH (OR = 1.05) and alleviated both FoL (OR = 0.96) and SoDS (OR = 0.92). Additionally, a higher level of SEH was positively correlated with a lower BMI, improved instrumental activities of daily living (I-ADL), and higher hemoglobin level. FoL was reinforced by the level of comorbidity, and SoDS was increased by impaired basic ADL.

Conclusion

Although SWB in geriatric inpatients can be explained by objective comorbidities and disabilities, the good motor function (i.e., a TUG test outcome of less than about 20 s) and a higher level of education were the general predictors that exert an independent beneficial impact on all three SWB indicators.

Health-related quality of life in older depressed psychogeriatric patients: one year follow-up

Background

Knowledge about long-term change in health related quality of life (HQoL) among older adults after hospitalization for treatment of depression has clinical relevance. The aim was firstly to describe the change of HQoL one year after admission for treatment of depression, secondly to explore if improved HQoL was associated with remission of depression at follow-up and lastly to study how HQoL in patients with remission from depression were compared to a reference group of older persons without depression.

Method

This study had the one year follow-up information of 108 older patients (≥60 years), all hospitalized for depression at baseline, and a reference sample of 106 community-living older adults (≥60 years) without depression. HQoL was measured using the EuroQol Group’s EQ-5D Index and a visual analog scale (EQ-VAS). Depression and remission were diagnosed according to ICD-10. Socio-demographic variables (age, gender, and education), depressive symptom score (Montgomery-Aasberg Depression Rating Scale), cognitive functioning (Mini Mental State Examination scale), instrumental activities of daily living (the Lawton and Brody’s Instrumental Activities of Daily Living Scale), and poor general physical health (General Medical Health Rating) were included as covariates.

Results

HQoL had improved at follow-up for the total group of depressed patients, as indicated by better scores on the EQ-5D Index and EQ-VAS. In the multivariate linear regression model, improved EQ-5D Index and EQ-VAS was significantly better in those with remission of depression and those with better baseline physical health. In adjusted analyses, the HQoL in patients with remission from depression at follow-up did not differ from the HQoL in a reference group without depression.

Conclusion

Older hospital patients with depression who experienced remission one year after admission gained HQoL and their HQoL was comparable with the HQoL in a reference group of older adults without depression when adjusting for differences in socio-demographics and health conditions.

10-year trajectories of depressive symptoms and risk of dementia: a population-based study

BACKGROUND

Late-life depressive symptoms have been extensively studied for their relationship with incident dementia, but have been typically assessed at a single timepoint. Such an approach neglects the course of depression, which, given its remitting and relapsing nature, might provide further insights into the complex association of depression with dementia. We therefore repeatedly measured depressive symptoms in a population of adults over a decade to study the subsequent risk of dementia.

METHODS

Our study was embedded in the Rotterdam Study, a population-based study of adults aged 55 years or older in Rotterdam (Netherlands), ongoing since 1990. The cohort is monitored continuously for major events by data linkage between the study database and general practitioners. We examined a cohort of participants who were free from dementia, but had data for depressive symptoms from at least one examination round in 1993-95, 1997-99, or 2002-04. We assessed depressive symptoms with the validated Dutch version of the Center for Epidemiology Depression Scale (CES-D) and the Hospital Anxiety and Depression Scale-Depression. We used these data to identify 11-year trajectories of depressive symptoms by latent class trajectory modelling. We screened participants for dementia at each examination round and followed up participants for 10 years for incident dementia by latent trajectory from the third examination round to 2014. We calculated hazard ratios (HR) for dementia by assigned trajectory using two Cox proportional hazards models (model 1 adjusted for age and sex only, and model 2 adjusted additionally for APOEɛ4 carrier status, educational level, body-mass index, smoking, alcohol consumption, cognitive score, use of antidepressants, and prevalent disease status at baseline). We repeated the analyses censoring for incident stroke, restricting to Alzheimer's disease as an outcome, and accounting for mortality as a competing risk for dementia.

FINDINGS

From 1993-2004, we obtained data for depressive symptoms from at least one examination round for 3325 participants (median age: 74·88 years [IQR 70·62-80·06], 1995 [60%] women). We identified five trajectories of depressive symptoms in these 3325 individuals, characterised by maintained low CES-D scores (low; 2441 [73%]); moderately high starting scores but then remitting (decreasing; 369 [11%]); low starting scores, increasing, then remitting (remitting; 170 [5%]); low starting scores that steadily increased (increasing; 255 [8%]); and maintained high scores (high; 90 [3%]). During 26 330 person-years, 434 participants developed incident dementia. Only the trajectory with increasing depressive symptoms was associated with a higher risk of dementia compared with the low depressive symptom trajectory, using model 2 (HR 1·42, 95% CI 1·05-1·94; p=0·024). Additionally, only the increasing trajectory was associated with a higher risk of dementia compared with the low trajectory after censoring for incident stroke (1·58, 1·15-2·16; p=0·0041), restricting to Alzheimer's disease as an outcome (1·44, 1·03-2·02; p=0·034), and accounting for mortality as a competing risk (1·45, 1·06-1·97; p=0·019).

INTERPRETATION

Risk of dementia differed with different courses of depression, which could not be captured by a single assessment of depressive symptoms. The higher risk of dementia only in the increasing trajectory suggests depression might be a prodrome of dementia.

FUNDING

Erasmus Medical Center; ZonMw; the Netherlands Ministry of Education Culture and Science; and the Netherlands Ministry for Health, Welfare and Sports.

Antidepressant, anxiolytic and procognitive effects of rivastigmine and donepezil in the chronic mild stress model in rats

BACKGROUND

The treatment of depression in old age is complicated by frequent co-morbidity with cognitive impairment. Anti-dementia drugs have some efficacy to improve cognitive performance and there is an inconsistent literature regarding the effect of such drugs on depressive symptoms. Here, we have investigated whether anti-dementia drugs would have antidepressant-like and pro-cognitive effects in a well-validated animal model of depression and cognitive impairment, chronic mild stress (CMS).

METHODS

Rats were subjected to CMS for a total of 8 weeks. After 2 weeks, subgroups of stressed and non-stressed animals were treated daily, for 5 weeks followed by 1 week of drug withdrawal, with vehicle, imipramine (10 mg/kg), rivastigmine (2 mg/kg), donepezil (0.3 mg/kg) or memantine (5 mg/kg). Sucrose intake was tested weekly, and animals were also tested in the elevated plus maze (at week 7) and in an object recognition task (at weeks 7 and 8).

RESULTS

CMS decreased sucrose intake, had an anxiogenic effect in the elevated plus maze, and impaired performance in the object recognition test. Imipramine, rivastigmine and donepezil normalized performance in all three tests. Memantine had anxiolytic and pro-cognitive effects, but did not reverse CMS-induced anhedonia.

DISCUSSION

The fact that all three anti-dementia drugs reversed CMS-induced cognitive impairment and that cholinesterase inhibitors, but not memantine, have antidepressant-like effects in this model suggest that different mechanisms may underlie CMS-induced anhedonia and cognitive impairment. We discuss the clinical implications of these findings.

Sleep Disturbances in the Elderly

Sleep disturbances are a common presenting symptom of older-age adults to their physicians. This article explores normal changes in sleep pattern with aging and primary sleep disorders in the elderly. Behavioral factors and primary psychiatric disorders affecting sleep in this population are reviewed. Further discussion examines sleep changes associated with 2 common forms of neurocognitive disorder: Alzheimer disease and Lewy Body Dementia. Common medical illnesses in the elderly are discussed in relation to sleep symptoms. Nonpharmacological and pharmacologic treatment strategies are summarized, with emphasis placed on risk of side effects in older adults. Future targets are considered.

Eating behaviors, mental health, and food intake are associated with obesity in older congregate meal participants

The relationship between eating behaviors, food intake, and mental health and the occurrence of obesity in older adults has rarely been investigated. Therefore, the objective of this study was to establish the associative links of these factors with two measures of obesity: class I obesity as indicated by body mass index (OB-BMI; BMI ≥ 30 kg/m²) and class I obesity as indicated by waist circumference (OB-WC; WC ≥ 43 inches for men and ≥ 42 inches for women). Older adults participating in the Older American's Act congregate meal program (N = 113, mean age = 74 years, 74% female, 45% African American) were assessed. Eating behaviors (cognitive restraint, uncontrolled eating, and emotional eating), food group choices (sweets, salty snacks, and fruits), and mental health indices (depression, anxiety, and stress) were recorded by questionnaire and related to measured occurrence of OB-BMI and OB-WC. In a series of multivariate logistical regression models, we found cognitive restraint to be consistently and robustly associated with both measures of obesity. In the fully adjusted model, cognitive restraint, consumption of sweets, anxiety, and lack of depression were associated with OB-WC. In summary, we found an association of obesity with abnormal eating behaviors, certain food group intakes, and mental health symptoms in this population. These findings may guide the development of future weight management interventions in a congregate meal setting.

Neuromodulation therapies for geriatric depression

Depression is frequent in old age and its prognosis is poorer than in younger populations. The use of pharmacological treatments in geriatric depression is limited by specific pharmacodynamic age-related factors that can diminish tolerability and increase the risk of drug interactions. The possibility of modulating cerebral activity using brain stimulation techniques could result in treating geriatric depression more effectively while reducing systemic side effects and medication interactions. This may subsequently improve treatment adherence and overall prognosis in the older patient. Among clinically available neuromodulatory techniques, electroconvulsive therapy (ECT) remains the gold standard for the treatment of severe depression in the elderly. Studies have proven that ECT is more effective and has a faster onset of action than antidepressants in the treatment of severe, unipolar, geriatric depression and that older age is a predictor of rapid ECT response and remission. The application of novel and more tolerable forms of ECT for geriatric depression is currently being examined. Preliminary results suggest that right unilateral ultrabrief ECT (RUL-UB ECT) is a promising intervention, with similar efficacy to brief-pulse ECT and fewer adverse cognitive effects. Overall findings in repetitive transcranial magnetic stimulation (rTMS) suggest that it is a safe intervention in geriatric depression. Higher rTMS stimulation intensity and more treatments may need to be given in the elderly to achieve optimal results. There is no specific data on vagus nerve stimulation in the elderly. Transcranial direct current stimulation, magnetic seizure therapy and deep brain stimulation are currently experimental, and more data from geriatric samples is needed.

Autoantibodies in Human Diabetic Depression Inhibit Adult Neural Progenitor Cells In vitro and Induce Depressive-Like Behavior in Rodents

AIM

Diabetic depression increases in association with microvascular complications. We tested a hypothesis that circulating autoantibodies having anti-endothelial and anti-neuronal properties increase in subsets of diabetes with co-morbid depression.

METHODS

Protein-A eluates from plasma of 20 diabetic depression patients and 30 age-matched controls were tested for effects on endothelial cell survival, neurite outgrowth in rat pheochromocytoma (PC12) cells, or process extension and survival in adult rat dentate gyrus neural progenitor cells. The protein-A eluates from depressed or non-depressed, diabetic patients were injected (via intracerebroventricular route) into mice and 7-10 days later behavioral tests (sucrose preference, and tail suspension tests) were conducted to determine whether the autoantibodies induced anhedonia or despair.

RESULTS

Diabetic depression (n=20) autoantibodies caused a significant inhibition of PC12 cell neurite outgrowth (P<0.001) or endothelial cell proliferation compared to autoantibodies in control, diabetic (n=20) or non-diabetic (n=10) patients without depression. Process extension and survival in adult rat dentate gyrus neural progenitor cells was significantly reduced (P<0.001) by diabetic depression autoantibodies (n= 11) compared to the effects from similar concentrations (5-7 μg/mL) of autoantibodies in diabetic (n=12) or non-diabetic patients without depression (n=7). Ten micromolar concentrations of Y27632, a selective Rho-Associated Protein Kinase (ROCK) inhibitor, significantly prevented (P<0.0001) neural progenitor cell process retraction induced by diabetes depression autoantibodies (n=5). Mice treated with diabetic depression autoantibodies (n=16 from two different patients' autoantibodies) exhibited significantly reduced (P=0.027) sucrose preference (anhedonia) compared to mice treated with diabetic control autoantibodies (n=16 from two different patients' autoantibodies).

CONCLUSION

These data suggest that autoantibodies in a subset of older adult diabetic depression inhibit endothelial cell survival, and impair process extension and survival in adult dentate gyrus neural progenitor cells in vitro.

Hearing care for elders: a personal reflection on participatory action learning with primary care providers

PURPOSE

This report is a reflective critical narrative of the authors' experience with an interdisciplinary collaboration of primary care providers (PCPs) and hearing health care providers (HHCPs) that followed the principles of participatory action research/learning. The goal for this report is to describe the 1st author's observed barriers to PCPs' willingness to learn about hearing health care and the subsequent facilitators to learning.

METHOD

A team of PCPs and HHCPs created the "Communication: Hearing Loss in Elders" educational module. The module included (a) prereading developed from a combination of literature reviews and contextual factors and (b) a case study.

RESULTS

The authors present the list of topics included in the module, and they reflect on why and how these topics were deemed important by the team. In particular, 2 topics were identified for motivating PCPs' behavior regarding hearing health care: (a) the overlap in symptoms and possible causation among depression, dementia, and hearing loss and (b) how hearing can affect efficiency of care regarding other health issues.

CONCLUSIONS

This personal reflective narrative gives the authors' opinions about what can make for a successful collaboration and presents some hypotheses regarding information that may motivate behavior change with regard to hearing care.

Neuroticism in Remitted Major Depression: Elevated with Early Onset but Not Late Onset of Depression

BACKGROUND

The personality trait of neuroticism is strongly related to depression, but depression is etiologically heterogeneous. Late-onset depression (LOD) may be more closely related to vascular factors, and previous studies of neuroticism in LOD versus early-onset depression (EOD) have not been consistent.

METHOD

We examined neuroticism, extraversion and perceived stress in 88 fully remitted depressed patients with a mean age of 60 years and with a history of hospitalization for major depressive disorder. Patients were divided into those with onset after and those with onset before 50 years of age (LOD and EOD, respectively), and the two groups were compared both with each other and with matched control groups of healthy subjects.

RESULTS

EOD patients showed increased levels of neuroticism in comparison with both LOD and matched controls, who did not differ. The association between age of onset and neuroticism was confirmed in analyses based on age of depression onset as a continuous variable.

CONCLUSION

Neuroticism may be an etiological factor in EOD but not or less so in LOD. This finding contributes to the growing evidence for etiological differences between early- and late-onset late-life depression.

Major depressive disorder: mechanism-based prescribing for personalized medicine

Individual patients with depression present with unique symptom clusters - before, during, and even after treatment. The prevalence of persistent, unresolved symptoms and their contribution to patient functioning and disease progression emphasize the importance of finding the right treatment choice at the onset and the utility of switching medications based on suboptimal responses. Our primary goal as clinicians is to improve patient function and quality of life. In fact, feelings of well-being and the return to premorbid levels of functioning are frequently rated by patients as being more important than symptom relief. However, functional improvements often lag behind resolution of mood, attributed in large part to persistent and functionally impairing symptoms - namely, fatigue, sleep/wake disturbance, and cognitive dysfunction. Thus, patient outcomes can be optimized by deconstructing each patient's depressive profile to its component symptoms and specifically targeting those domains that differentially limit patient function. This article will provide an evidence-based framework within which clinicians may tailor pharmacotherapy to patient symptomatology for improved treatment outcomes.

Hospital outcomes in major depression among older adults: differences by alcohol comorbidity

OBJECTIVE

The prevalence of depression in older adults has been increasing over the last 20 years and is associated with economic costs in the form of treatment utilization and caregiving, including inpatient hospitalization. Comorbid alcohol diagnoses may serve as a complicating factor in inpatient admissions and may lead to overutilization of care and greater economic cost. This study sought to isolate the comorbidity effect of alcohol among older adult hospital admissions for depression.

METHODS

We analyzed a subsample (N = 8,480) of older adults (65+) from the 2010 Nationwide Inpatient Sample who were hospitalized with primary depression diagnoses, 7,741 of whom had depression only and 739 of whom also had a comorbid alcohol disorder. To address potential selection bias based on drinking and health status, propensity score matching was used to compare length of stay, total costs, and disposition between the two groups.

RESULTS

Bivariate analyses showed that older persons with depression and alcohol comorbidities were more often male (59.9% versus 34.0%, p <.001) and younger (70.9 versus 75.9 years, p <.001) than those with depression only. In terms of medical comorbidities, those with depression and alcohol disorders experienced more medical issues related to substance use (e.g., drug use diagnoses, liver disease, and suicidality; all p <.001), while those with depression only experienced more general medical problems (e.g., diabetes, renal failure, hypothyroid, and dementia; all p <.001). Propensity score matched models found that alcohol comorbidity was associated with shorter lengths of stay (on average 1.08 days, p <.02) and lower likelihood of post-hospitalization placement in a nursing home or other care facility (OR = 0.64, p <.001). No significant differences were found in overall costs or likelihood of discharge to a psychiatric hospital.

CONCLUSIONS

In older adults, depression with alcohol comorbidity does not lead to increased costs or higher levels of care after discharge. Comorbidity may lead to inpatient hospitalization at lower levels of severity, and depression with alcohol comorbidity may be qualitatively different than non-comorbid depression. Additionally, increased costs and negative outcomes in this population may occur at other levels of care such as outpatient services or emergency department visits.