Alina Dyachenko

Adherence to colorectal cancer screening guidelines in Canada

BackgroundTo identify correlates of adherence to colorectal cancer (CRC) screening guidelines in average-risk Canadians.Methods2003 Canadian Community Health Survey Cycle 2.1 respondents who were at least 50 years old, without past or present CRC and living in Ontario, Newfoundland, Saskatchewan, and British Columbia were included. Outcomes, defined according to current CRC screening guidelines, included adherence to: i) fecal occult blood test (FOBT) (in prior 2 years), ii) endoscopy (colonoscopy/sigmoidoscopy) (prior 10 years), and iii) adherence to CRC screening guidelines, defined as either (i) or (ii). Generalized estimating equations regression was employed to identify correlates of the study outcomes.ResultsOf the 17,498 respondents, 70% were non-adherent CRC screening to guidelines. Specifically, 85% and 79% were non-adherent to FOBT and endoscopy, respectively. Correlates for all outcomes were: having a regular physician (OR = (i) 2.68; (ii) 1.91; (iii) 2.39), getting a flu shot (OR = (i) 1.59; (ii) 1.51; (iii) 1.55), and having a chronic condition (OR = (i) 1.32; (ii) 1.48; (iii) 1.43). Greater physical activity, higher consumption of fruits and vegetables and smoking cessation were each associated with at least 1 outcome. Self-perceived stress was modestly associated with increased odds of adherence to endoscopy and to CRC screening guidelines (OR = (ii) 1.07; (iii) 1.06, respectively).ConclusionHealthy lifestyle behaviors and factors that motivate people to seek health care were associated with adherence, implying that invitations for CRC screening should come from sources that are independent of physicians, such as the government, in order to reduce disparities in CRC screening.

Dietary patterns and risk of cancer of various sites in the Norwegian European Prospective Investigation into Cancer and Nutrition cohort: the Norwegian Women and Cancer study.

An indicator of common diets among groups of individuals can be found by identifying dietary patterns. We found previously six dietary patterns in the Norwegian European Prospective Investigation into Cancer and Nutrition cohort and labelled them fish, healthy, average, western, bread and alcohol. We examined the relationship between the different patterns and risk of total cancer, breast cancer and gastrointestinal cancers in 34 471 women from the Norwegian European Prospective Investigation into Cancer and Nutrition cohort, in which there were 1355 cancer cases. The hazard ratios and their corresponding 95% confidence intervals were estimated using Cox proportional hazards regression. Stratified analysis on menopausal status and smoking status was performed. Alcohol, meat, fish and fruit and vegetable consumption are suspected to have an influence on different cancers; thus we decided to perform stratified analysis on high versus low consumption of the above-mentioned variables as well. We found no overall relationship between cancers and the six different dietary patterns in this study. When stratifying on alcohol consumption, fruit and vegetable consumption and fatty fish consumption, there was a statistically higher risk of total cancer and breast cancer with high alcohol consumption, and a significantly higher risk of breast cancer with low consumption of fruit and vegetables or with low consumption of fatty fish in the western group only. A significantly higher risk of total cancer with low intake of fatty fish in the alcohol group was also observed.

Health services use for mental health problems by community-living seniors with depression.

BACKGROUND The literature on health services (HS) use for mental health problems by community-living seniors with depression is sparse. This study aimed to characterize patterns of HS use for mental health problems by seniors with depressive disorders and symptoms during the previous 12 months. METHOD The study used data from the Canadian Community Health Survey Cycle 1.2: Mental Health and Well-Being (N = 7736). Information was collected on demographic, social, mental, physical and functional variables and HS use for mental health problems. We obtained simple univariate and bivariate descriptions of the data and developed multivariate predictive models for each of the HS utilization variables. RESULTS Rates of any HS use for mental health problems ranged from 1.8% for those with no depressive symptoms to 31.1% for those with major depression. Variables predicting increased HS use were: depressive disorder or symptoms, clinically significant distress or impairment, age 65-84, single, post-secondary education, religiousness, disability, co-morbid mental disorder and fewer friends and positive social interactions. Variables predicting HS use among depressed seniors were physical health, psychiatric co-morbidity and activity limitation. CONCLUSION Community-living seniors with major depression, co-morbid major depression and depressive symptoms were more likely to use psychiatrist, family physician, other professional and self-help services for mental health problems but less than a third actually did so.

Observer-rated depression in long-term care: frequency and risk factors.

The objectives of this study were: (1) to describe the prevalence and 6-month incidence of observer-rated depression in residents age 65 and over of long-term care (LTC) facilities; (2) to describe risk factors for depression, at baseline and over time. A multisite, prospective observational study was conducted in residents aged 65 and over of 7 LTC facilities. The Cornell Scale for Depression in Dementia (CSDD) was completed by nurses monthly for 6 months. We measured demographic, medical, and functional factors at baseline and monthly intervals, using data from research assessments, nurse interviews, and chart reviews. 274 residents were recruited and completed baseline depression assessments. The prevalence of depression (CSDD score of 6+) was 19.0%. The incidence of depression among those without prevalent depression was 73.3 per 100 person-years. A delirium diagnosis, pain, and diabetes were independently associated with prevalent depression. CSDD score at baseline and development of severe cognitive impairment at follow-up were independent risk factors for incident depression. A diagnosis of delirium and uncorrected visual impairment at follow-up occurred concurrently with incident depression. The results of this study have implications for the detection and prevention of depression in LTC. Delirium diagnosis, pain and diabetes at baseline were associated with prevalent depression; depression symptoms at baseline and development of severe cognitive impairment at follow-up were risk factors for incident depression.

Environmental factors predict the severity of delirium symptoms in long-term care residents with and without delirium.

To identify potentially modifiable environmental factors (including number of medications) associated with changes over time in the severity of delirium symptoms and to explore the interactions between these factors and resident baseline vulnerability.

Symptoms of Delirium Occurring Before and After Episodes of Delirium in Older Long-Term Care Residents

To describe Confusion Assessment Method (CAM) core symptoms of delirium occurring before and after incident episodes of delirium in older long‐term care (LTC) residents. A secondary objective was to describe the mean number of symptoms before and after episodes by dementia status.

Medication use and nonadherence to psychoactive medication for mental health problems by community-living Canadian seniors with depression.

Objectives: To determine the relation between level of depression and psychoactive medication use and nonadherence in Canadian seniors, given that late-life depression is a common, serious mental health problem in Canada. Methods: Canadian Community Health Survey—Mental Health and Well-Being respondents aged 65 years and older (n = 7736) comprised the study sample. Using the Composite International Diagnostic Interview to assess depressive symptoms, we created 4 depression levels to capture a spectrum of depressive disorders and (or) symptoms: major depression, comorbid major depression, depressive symptoms, and no depressive symptoms. Psychoactive medications assessed included sleep aids, anxiolytics, and mood stabilizers and (or) antidepressants (AD). Nonadherence was defined as either not taking medication as recommended or taking medication at a lower dosage than prescribed. Results: In total, 22.5% of respondents took psychoactive medication for a mental health problem in the previous 12 months. Psychoactive medication use was 46.8% for major depression, 43.1% for comorbid major depression, 34.0% for depressive symptoms, and 17.6% for no depressive symptoms. Rates of psychoactive medication use ranged from 46.5% of those with major depression, to 17.6% of those with no depressive symptoms. Overall, the rate of nonadherence to psychoactive medication was 31%; rates were highest among those with depressive symptoms (37.4%) and lowest among those with no depressive symptoms (27.4%). All 3 depressive categories were associated with greater odds of use and nonadherence. Conclusion: All 3 depression categories were associated with increased use of and nonadherence to psychoactive medication; however, rates of AD and (or) mood stabilizer use for clinically significant depression were low.

Symptoms of delirium predict incident delirium in older long-term care residents

BACKGROUND Detection of long-term care (LTC) residents at risk of delirium may lead to prevention of this disorder. The primary objective of this study was to determine if the presence of one or more Confusion Assessment Method (CAM) core symptoms of delirium at baseline assessment predicts incident delirium. Secondary objectives were to determine if the number or the type of symptoms predict incident delirium. METHODS The study was a secondary analysis of data collected for a prospective study of delirium among older residents of seven LTC facilities in Montreal and Quebec City, Canada. The Mini-Mental State Exam (MMSE), CAM, Delirium Index (DI), Hierarchic Dementia Scale, Barthel Index, and Cornell Scale for Depression were completed at baseline. The MMSE, CAM, and DI were repeated weekly for six months. Multivariate Cox regression models were used to determine if baseline symptoms predict incident delirium. RESULTS Of 273 residents, 40 (14.7%) developed incident delirium. Mean (SD) time to onset of delirium was 10.8 (7.4) weeks. When one or more CAM core symptoms were present at baseline, the Hazard Ratio (HR) for incident delirium was 3.5 (95% CI = 1.4, 8.9). The HRs for number of symptoms present ranged from 2.9 (95% CI = 1.0, 8.3) for one symptom to 3.8 (95% CI = 1.3, 11.0) for three symptoms. The HR for one type of symptom, fluctuation, was 2.2 (95% CI = 1.2, 4.2). CONCLUSION The presence of CAM core symptoms at baseline assessment predicts incident delirium in older LTC residents. These findings have potentially important implications for clinical practice and research in LTC settings.

Delirium superimposed on dementia: defining disease states and course from longitudinal measurements of a multivariate index using latent class analysis and hidden Markov chains.

BACKGROUND The study of mental disorders in the elderly presents substantial challenges due to population heterogeneity, coexistence of different mental disorders, and diagnostic uncertainty. While reliable tools have been developed to collect relevant data, new approaches to study design and analysis are needed. We focus on a new analytic approach. METHODS Our framework is based on latent class analysis and hidden Markov chains. From repeated measurements of a multivariate disease index, we extract the notion of underlying state of a patient at a time point. The course of the disorder is then a sequence of transitions among states. States and transitions are not observable; however, the probability of being in a state at a time point, and the transition probabilities from one state to another over time can be estimated. RESULTS Data from 444 patients with and without diagnosis of delirium and dementia were available from a previous study. The Delirium Index was measured at diagnosis, and at 2 and 6 months from diagnosis. Four latent classes were identified: fairly healthy, moderately ill, clearly sick, and very sick. Dementia and delirium could not be separated on the basis of these data alone. Indeed, as the probability of delirium increased, so did the probability of decline of mental functions. Eight most probable courses were identified, including good and poor stable courses, and courses exhibiting various patterns of improvement. CONCLUSION Latent class analysis and hidden Markov chains offer a promising tool for studying mental disorders in the elderly. Its use may show its full potential as new data become available.

Model-Based Clustering of Longitudinal Data: Application to Modeling Disease Course and Gene Expression Trajectories

We consider the problem of clustering time-dependent data. The model is a mixture of regressions, with variance–covariance matrices that are allowed to vary within the extended linear mixed model family. We discuss applications to biomedical data and analyze two longitudinal data sets: one on patients with delirium, and the other on mosquito gene expression following infection.