Impact of sleep duration and sleep disturbances on the incidence of dementia and Alzheimer's disease: A 10-year follow-up study.

The nature of the relationship between sleep problems and dementia remains unclear. This study investigated the relationship between sleep measures and dementia in older adults (≥ 65) using data from the English Longitudinal Study of Ageing (ELSA) and further investigated the causal association in Mendelian randomization (MR) analysis. In total of 7,223 individuals, 5.7 % developed dementia (1.7 % Alzheimer's disease (AD)) within an average of 8 (± 2.9) years. Cox regression models and MR were employed. Long sleep duration (>8 h) was associated with 64 % increased risk of incident dementia and 2-fold high risk of AD compared to ideal sleep duration (7-8 h). This association was particularly evident in older-older adults (≥70 years) and those who consumed alcohol. Short sleep duration (<7 h) was associated with lower risk of incident dementia among older-older but higher risk among younger-older adults. Sleep disturbances and perceived sleep quality were not associated with dementia or AD. The MR study did not reveal causal associations between sleep duration and dementia. These findings suggest that self-reported short sleep in younger-older and long sleep in older-older adults and those with frequent alcohol consumption are associated with dementia. Early detection of these sleep patterns may help identify individuals at higher dementia risk.

Interactive association between insomnia symptoms and sleep duration for the risk of dementia-a prospective study in the Swedish National March Cohort.

OBJECTIVE: Given the importance of sleep in maintaining neurocognitive health, both sleep duration and quality might be component causes of dementia. However, the possible role of insomnia symptoms as risk factors for dementia remain uncertain. METHODS: We prospectively studied 22,078 participants in the Swedish National March Cohort who were free from dementia and stroke at baseline. Occurrence of dementia was documented by national registers during a median follow-up period of 19.2 years. Insomnia symptoms and sleep duration were ascertained by Karolinska Sleep Questionnaire. Multivariable Cox proportional hazards models were used to estimate hazard ratios (HR) and 95% confidence intervals (CI). RESULTS: Compared to participants without insomnia at baseline, those who reported any insomnia symptom experienced a greater incidence of dementia during follow-up (HR 1.08, 95% CI: 1.03, 1.35). Difficulty initiating sleep versus non-insomnia (HR 1.24, 95% CI: 1.02, 1.52), but not difficulty maintaining sleep or early morning awakening was associated with an increased risk of dementia. Short sleep duration was associated with increased risk of dementia (6 h vs. 8 h, HR 1.29, 95% CI: 1.11-1.51; 5 h vs. 8 h, HR 1.26, 95% CI: 1.00-1.57). Stratified analyses suggested that insomnia symptoms increased the risk of dementia only amongst participants with ≥7 h sleep (vs. non-insomnia HR 1.24, 95% CI: 1.00-1.54, P = 0.05), but not amongst short sleepers (<7 h). Short sleep duration also did not further inflate the risk of dementia amongst insomniacs. CONCLUSION: Insomnia and short sleep duration increase the risk of dementia amongst middle-aged to older adults.

Influence of chronic diseases on the occurrence of depression: A 13-year follow-up study from the Survey of Health, Ageing and Retirement in Europe.

The causal association between chronic diseases and depression remains unclear. This study aimed to explore the effects of types and number of chronic diseases on the risk of depression using data from the Survey of Health, Ageing and Retirement in Europe (SHARE). A self-admitted questionnaire was used to obtain data on 14 predefined chronic diseases and the European-Depression Scale (EURO-D) was used to assess depression. Among the 16,080 baseline depression-free participants aged 50+, 31.29% (5032) developed depression over 13 years. Multivariate Cox regression models showed that individuals with any chronic diseases were at higher risk of new onset depression compared to disease-free participants. The risk of new onset depression increased with an increasing number of diseases among both younger (50-64) and older (65+) adults. Individuals with heart attack, stroke, diabetes, chronic lung disease, and arthritis were at increased risk of depression across age groups. However, some age-specific associations were observed, with cancer increasing depression risk among younger- and peptic ulcer, Parkinson's disease and cataracts increasing depression risk among older adults. These findings highlight the importance of managing chronic diseases, especially among those with more than two diseases, to prevent the development of depression among middle-aged and older adults.

Prolonging working life among blue-collar workers: The buffering effect of psychosocial job resources on the association between physically demanding and hazardous work and retirement timing.

The need to delay retirement timing has been acknowledged in Western countries due to demographic ageing. The aim of the present study was to examine the buffering effects of job resources (decision authority, social support, work-time control, and rewards) on the association of exposures to physically demanding work tasks and physically hazardous work environment with non-disability retirement timing. Results from discrete-time event history analyses, in a sample of blue-collar workers (n = 1741; 2792 observations) from the nationwide longitudinal Swedish Longitudinal Occupational Survey of Health (SLOSH), supported that decision authority and social support may buffer the negative impact of heavy physical demands on working longer (continuing working vs retiring). Stratified analyses by gender showed that the buffering effect of decision authority remained statistically significant for men, while that of social support remained statistically significant for women. Moreover, an age effect was displayed, such that a buffering effect of social support on the association of heavy physical demands and high physical hazards with working longer were found among older men (≥64 years), but not younger (59-63 years). The findings suggest that heavy physical demands should be reduced, however, when not feasible physical demands should be accompanied by social support at work for delaying retirement.

Social Health and Cognitive Change in Old Age: Role of Brain Reserve.

OBJECTIVE: Individual aspects of social health (SH; eg, network, engagement, support) have been linked to cognitive health. However, their combined effect and the role of the structural properties of the brain (brain reserve [BR]) remain unclear. We investigated the interplay of SH and BR on cognitive change in older adults. METHODS: Within the Swedish National Study on Aging and Care-Kungsholmen, 368 dementia-free adults aged ≥60 years with baseline brain magnetic resonance imaging were followed over 12 years to assess cognitive change. A measure of global cognition was computed at each of the 5 waves of assessment by averaging domain-specific Z scores for episodic memory, perceptual speed, semantic memory, and letter and category fluency. An SH composite score was computed at baseline by combining leisure activities and social network. BR was proxied by total brain tissue volume (TBTV). Linear mixed models (adjusted for sociodemographic, vascular, and genetic factors) were used to estimate cognitive trajectories in relation to SH and TBTV. Interaction analysis and stratification were used to examine the interplay between SH and TBTV. RESULTS: Moderate-good SH (n = 245; vs poor, ß-slope = 0.01, 95% confidence interval [CI] = 0.002-0.02, p = 0.018) and moderate-to-large TBTV (n = 245; vs small, ß-slope = 0.03, 95% CI = 0.02-0.04, p < 0.001) were separately associated with slower cognitive decline. In stratified analysis, moderate-good SH was associated with higher cognitive levels (but not change) only in participants with moderate-to-large TBTV (ß-intercept = 0.21, 95% CI = 0.06-0.37, p < 0.01; interaction SH * TBTV, p < 0.05). INTERPRETATION: Our findings highlight the interplay between SH and BR that likely unfolds throughout the entire life course to shape old-age cognitive outcomes. ANN NEUROL 2023;93:844-855.

Sleep Mediates the Association Between Stress at Work and Incident Dementia: Study From the Survey of Health, Ageing and Retirement in Europe.

BACKGROUND: Both psychosocial stress at work and sleep disturbance may predispose impaired cognitive function and dementia in later life. However, whether sleep plays a mediating role for the link between stress at work and subsequent dementia has yet to be investigated. METHODS: Data from the Survey of Health, Ageing and Retirement in Europe were used for the study. A cohort of 7 799 dementia-free individuals (aged 71.1 ± 0.2 years) were followed up for a median of 4.1 years for incident dementia. Job demand and control were estimated using questions derived from the Karasek's Job Content Questionnaire. Sleep disturbance was ascertained by a question in the EURO-Depression scale. Cox proportional hazard models adjusted for age, sex, education, cognitive test score, and other potential covariates were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) of dementia in relation to different job strain levels. RESULTS: An interaction between job demand and sleep disturbance regarding the risk of dementia was detected. Data suggested a protective role of high-level job demand for dementia in individuals with sleep disturbance (HR [95% CI]: 0.69 [0.47, 1.00]) compared with low job demand. A 4-category job strain model based on the combination of job demand and job control levels suggested that among individuals with sleep disturbance, passive job (low demand, low control) was associated with a higher risk of dementia (1.54 [1.01, 2.34]), compared to active job (high demand, high control). CONCLUSION: The link between work-related stress and risk of dementia is limited to individuals suffering sleep disturbance.

Do good psychosocial working conditions prolong working lives? Findings from a prospective study in Sweden.

Due to an ageing population, governments in European countries are striving to keep older workers longer in the workforce. Remarkably few studies have paid attention to the influence of psychosocial working conditions on timing of retirement for older workers in and beyond normative retirement age. The aim of the present study was to examine whether good psychosocial working conditions contribute to prolonged working lives among older workers (59 years and above). A particular question was whether such conditions increase in importance with age. Seven waves (2006-2018) of the Swedish Longitudinal Occupational Survey of Health (SLOSH) were used (N = 6000, observations = 10,632). Discrete-time event history analyses showed that higher levels of job resources (decision authority [OR 1.13, 95% CI 1.06-1.22], skill use [OR 1.17, 95% CI 1.07-1.29], learning opportunities [OR 1.22, 95% CI 1.13-1.31], social support [OR 1.29 (95% CI 1.16-1.42], work-time control [OR 1.07, 95% CI 1.01-1.13], and reward [OR 1.40, 95% CI 1.24-1.57])-but not lower levels of job demands (quantitative and emotional demands or effort)-were associated with working longer (continued work two years later). Also, low effort-reward imbalance (OR 0.84 [95% CI 0.73-0.96]) was associated with working longer. In addition, skill use, work-time control, reward, and low effort-reward imbalance increased in importance with age for continued work. These results suggest that providing older workers with control over their work tasks, giving opportunities for learning and using their skills, as well as rewarding and acknowledging their achievements, may keep them in the workforce longer. Especially, job resources may grow in importance with age. Supplementary Information: The online version contains supplementary material available at 10.1007/s10433-021-00672-0.

What Do We Know about Social and Non-Social Factors Influencing the Pathway from Cognitive Health to Dementia? A Systematic Review of Reviews.

The heterogeneous and multi-factorial nature of dementia requires the consideration of all health aspects when predicting the risk of its development and planning strategies for its prevention. This systematic review of reviews provides a comprehensive synthesis of those factors associated with cognition in the context of dementia, identifying the role of social aspects and evidencing knowledge gaps in this area of research. Systematic reviews and meta-analyses from 2009-2021 were searched for within Medline, PsycINFO, CINAHL Complete, Cochrane, and Epistemonikos. Reviewers independently screened, reviewed, and assessed the records, following the PRISMA-2020 guidelines. From 314 included studies, 624 cognitive-related factors were identified, most of them risk factors (61.2%), mainly belonging to the group of 'somatic comorbidities' (cardiovascular disease and diabetes) and 'genetic predispositions'. The protective factors (20%) were mainly related to lifestyle, pointing to the Mediterranean diet, regular physical activity, and cognitively stimulating activities. Social factors constituted 9.6% of all identified factors. Research on biological and medical factors dominates the reviewed literature. Greater social support and frequent contact may confer some protection against cognitive decline and dementia by delaying its onset or reducing the overall risk; however, overall, our findings are inconsistent. Further research is needed in the fields of lifestyle, psychology, social health, and the protective factors against cognitive decline and dementia.

Work-Related Stress and Occurrence of Cardiovascular Disease: A 13-Year Prospective Study.

OBJECTIVE: The aim of the study is to investigate the influence of work-related psychological and physical stresses on risk of cardiovascular disease (CVD). METHODS: A total of 5651 CVD-free participants older than 50 years from the Survey of Health, Ageing and Retirement in Europe were followed up for 13 years to detect incident CVD. Work-related stress was assessed using job strain and job reward questionnaire. Cox regression model was used to estimate the association. RESULTS: High physical demands (hazard ratio [HR], 1.30) and low reward (HR, 1.19) compared with their counterparts, as well as active physical jobs (HR, 1.41) and high physical strain (HR, 1.45) in comparison with low physical strain were associated with higher risk of incident CVD after adjusting for confounders. However, combining physically stressful jobs with low reward did not further increase the CVD risk. CONCLUSIONS: Avoiding physically stressful jobs or providing appropriate reward may reduce the occurrence of CVD.

The Implication of Physically Demanding and Hazardous Work on Retirement Timing.

The need to retain individuals longer in the workforce is acknowledged in many high-income countries. The present study therefore aimed to examine the importance of physically demanding work tasks (PDWT) and physically hazardous work environment (PHWE) in relation to retirement timing among pensionable workers (≥61 years). A particular question was whether PDWT and PHWE increased in importance with age. Six waves (2008-2018) of the Swedish Longitudinal Occupational Survey of Health (SLOSH) were used (n = 5201; 56% women and 44% men; mean age at first survey was 61.0 (SD 2.0) years). Discrete time-event history analysis, stratified by socioeconomic position and gender, showed that among blue-collar workers, PDWT and PHWE were associated with an increased likelihood of retiring within the next two years. With increasing age, high-level PHWE was associated with higher probability of retiring among blue-collar men, whereas heavy PDWT was associated with lower probability of retiring among blue-collar women. Among white-collar workers, having at least some PDWT compared to no PDWT was associated with a lower likelihood of retiring within the next two years. With increasing age, exposure to PHWE was associated with higher probability of retiring among white-collar women. These results suggest that to delay retirements, organizations could offer their older employees, especially blue-collar workers and the oldest white-collar women, alternatives to PDWT and PHWE.

Nomograms for Predicting Cancer-Specific Survival of Patients with Gingiva Squamous Cell Carcinoma: A Population-Based Study.

OBJECTIVE: The use of the traditional American Joint Committee on Cancer (AJCC) staging system alone has limitations in predicting the survival of gingiva squamous cell carcinoma (GSCC) patients. We aimed to establish a comprehensive prognostic nomogram with a prognostic value similar to the AJCC system. METHODS: Patients were identified from SEER database. Variables were selected by a backward stepwise selection method in a Cox regression model. A nomogram was used to predict cancer-specific survival rates for 3, 5 and 10 years in patients with GSCC. Several basic features of model validation were used to evaluate the performance of the survival model: consistency index (C-index), receiver operating characteristic (ROC) curve, calibration chart, net weight classification improvement (NRI), comprehensive discriminant improvement (IDI) and decision curve analysis (DCA). RESULTS: Multivariate analyses revealed that age, race, marital status, insurance, AJCC stage, pathology grade and surgery were risk factors for survival. In particular, the C-index, the area under the ROC curve (AUC) and the calibration plots showed good performance of the nomogram. Compared to the AJCC system, NRI and IDI showed that the nomogram has improved performance. Finally, the nomogram's 3-year and 5-year and 10-year DCA curves yield net benefits higher than traditional AJCC, whether training set or a validation set. CONCLUSION: We developed and validated the first GSCC prognosis nomogram, which has a better prognostic value than the separate AJCC staging system. Overall, the nomogram of this study is a valuable tool for clinical practice to consult patients and understand their risk for the next 3, 5 and 10 years.

Working life job strain status and cognitive aging in Europe: A 12-year follow-up study.

BACKGROUND: To examine the association of job strain with cognitive ability and the influence of life-course job strain on later life cognitive decline. METHODS: Data were derived from six waves of the Survey of Health, Aging, and Retirement in Europe. The study sample consists of 13349 participants aged 50 to 98 years at wave 2 and has been followed up for 12-years. Job strain status across working life was assessed using a short demand-control job strain model containing two core dimensions: job demands and job control collected in wave 3. Cognitive abilities concerning episodic memory was assessed by immediate recall and delayed recall tests, executive function was evaluated by verbal fluency test collected in all waves (waves 2-7) except wave 3. Mixed-effects model was used to estimate working life job strain and its cumulative effect on cognitive decline. RESULTS: Both passive and high strain jobs were associated with lower levels of cognitive ability (episodic memory and verbal fluency) in comparison with active job. Long exposure to active- or low strain-job was associated with higher cognitive ability whereas long exposure to passive job or moderate duration of high strain job was associated with lower cognitive ability. The rate of memory decline was positively related to moderate duration of passive job and negatively related to long-term exposure to low strain job. LIMITATIONS: Information on working conditions was based on self-reported recollections. CONCLUSIONS: Working life variation in job strain status and their duration may explain individual differences in cognitive ability in later life.

Depressive symptoms and cognitive impairment: A 10-year follow-up study from the Survey of Health, Ageing and Retirement in Europe.

BACKGROUND: Depressive symptoms and cognitive impairment often coexisted in the elderly. This study investigates the effect of late-life depressive symptoms on risk of mild cognitive impairment (MCI). METHODS: A total of 14,231 dementia- and MCI free participants aged 60+ from the Survey of Health, Ageing, and Retirement in Europe were followed-up for 10 years to detect incident MCI. MCI was defined as 1.5 standard deviation (SD) below the mean of the standardized global cognition score. Depressive symptoms were assessed by a 12-item Europe-depression scale (EURO-D). Severity of depressive symptoms was grouped as: no/minimal (score 0-3), moderate (score 4-5), and severe (score 6-12). Significant depressive symptoms (SDSs) were defined as EURO-D score ≥ 4. RESULTS: During an average of 8.2 (SD = 2.4)-year follow-up, 1,352 (9.50%) incident MCI cases were identified. SDSs were related to higher MCI risk (hazard ratio [HR] = 1.26, 95% confidence intervals [CI]: 1.10-1.44) in total population, individuals aged 70+ (HR = 1.35, 95% CI: 1.14-1.61) and women (HR = 1.28, 95% CI: 1.08-1.51) in Cox proportional hazard model adjusting for confounders. In addition, there was a dose-response association between the severity of depressive symptoms and MCI incidence in total population, people aged ≥70 years and women (p-trend <0.001). CONCLUSIONS: Significant depressive symptoms were associated with higher incidence of MCI in a dose-response fashion, especially among people aged 70+ years and women. Treating depressive symptoms targeting older population and women may be effective in preventing MCI.

Sex differences in dementia and response to a lifestyle intervention: Evidence from Nordic population-based studies and a prevention trial.

INTRODUCTION: Evidence on sex differences in the risk for dementia has been mixed. The goal was to assess sex differences in the development of dementia, and in the effects of a lifestyle intervention. METHODS: Two strategies were adopted, one using combined data from three large Nordic population-based cohort studies (n = 2289), adopting dementia as outcome, and 2-year multidomain lifestyle intervention (n = 1260), adopting cognitive change as outcome. RESULTS: There was higher risk for dementia after age 80 years in women. The positive effects of the lifestyle intervention on cognition did not significantly differ between men and women. Sex-specific analyses suggested that different vascular, lifestyle, and psychosocial risk factors are important for women and men in mid- and late-life. CONCLUSION: Women had higher risk for dementia among the oldest individuals. Lifestyle interventions may be effectively implemented among older men and women.

The relationship between chronic diseases and depression in middle-aged and older adults: A 4-year follow-up study from the China Health and Retirement Longitudinal Study.

BACKGROUND: Evidence of the association between common chronic diseases and depression is sparse. METHODS: Totally 7819 participants aged 45+ without depression at baseline were followed-up (2011-2015) to detect incident depression. Chronic diseases and depression were defined by self-reported diagnosis and the Center for Epidemiological Studies Depression Scale (CES-D10), respectively. Cox proportional hazards model was used to explore the association between chronic diseases and depression adjusting for age, gender, education, marital/living conditions, area, smoking, drinking, economic status, BMI and health insurance. RESULTS: During an average of 3.42 years follow-up, 2271 participants developed depression (85 per 1000 person-year). Chronic diseases were related to significantly higher risk of depression (HR = 1.38). A higher risk of depression was also associated with specific diseases: stomach/other digestive diseases (HR = 1.19), diabetes (HR = 1.22), arthritis/rheumatism (HR = 1.30), and kidney diseases (HR = 1.34) (P < 0.05). The risk of depression increased with increasing in the number of chronic diseases (1: HR = 1.27, 2: HR = 1.49, and 3+: HR = 1.51, P-trend < 0.001). No significant difference was observed across age, gender, education, and area. LIMITATIONS: Chronic diseases and depression were based on self-reported diagnosis and measurement scale, respectively, which could lead to information bias. Some unmeasured confounders might have biased the results. CONCLUSIONS: The occurrence of depression in people aged 45+ is associated with number of chronic diseases in a dose-response fashion. These results may provide guidance on preventing depression and improving the quality of life in middle and late adulthood.

Shared risk and protective factors between Alzheimer's disease and ischemic stroke: A population-based longitudinal study.

INTRODUCTION: Stroke, especially ischemic stroke's (IS) link with Alzheimer's disease (AD) remains unclear. METHODS: This prospective cohort study included 2459 AD- and cerebrovascular disease-free older adults at baseline (mean age 71.9 ± 10.3 years, Stockholm, Sweden). Using Cox regressions, shared risk factors (SRFs) and shared protective factors (SPFs) between AD and IS were recognized when their hazard ratios in both AD and IS models were significant and in the same direction. RESULTS: During the follow-up period of up to 15 years, 132 AD and 260 IS mutually exclusive cases were identified. SRFs were low education, sedentary lifestyle, and heart diseases. High levels of psychological well-being, actively engaging in leisure activities, and a rich social network were SPFs. Having ≥1 SPF reduced 47% of AD and 28% of IS risk among people with a low risk profile (<2 SRFs), and 38% of AD and 31% of IS risk with a high risk profile (≥2 SRFs). In total, 57.8% of AD/IS cases could be prevented if individuals have ≥1 SPF and no SRF. DISCUSSION: AD and IS share risk/protective profiles, and SPFs seem to counteract the adverse effects of SRFs on both AD and IS.

Mid- to late-life migraine diagnoses and risk of dementia: a national register-based follow-up study.

BACKGROUND: Previous studies found an association between migraine and dementia, which are two leading causes of disability. However, these studies did not differentiate between migraine types and did not investigate all prevalent dementia subtypes. The main objective of this national register-based study was to investigate whether migraine was a risk factor for dementia. Additionally, we explored potential differences in dementia risk for migraine with and without aura. METHODS: We obtained data on birth cohorts born between 1935 and 1956 (n = 1,657,890) from Danish national registers. Individuals registered with migraine before age 59 (n = 18,135) were matched (1:5) on sex and birthdate with individuals without migraine (n = 1,378,346). Migraine was defined by International Classification of Diseases (ICD) diagnoses and dementia was defined by ICD diagnoses and anti-dementia medication. After matching, 62,578 individuals were eligible for analysis. For the statistical analyses, we used Cox regression models and adjusted for socio-demographic factors and several psychiatric and somatic morbidities. RESULTS: During a median follow-up time of 6.9 (IQR: 3.6-11.2) years, 207 individuals with migraine developed dementia. Compared with individuals without migraine, we found a 50% higher rate of dementia among individuals with migraine (HR = 1.50; 95% CI: 1.28-1.76). Individuals without aura had a 19% higher rate of dementia (HR = 1.19; 95% CI: 0.84-1.70), and individuals with aura had a two times higher rate of dementia (HR = 2.11; 95% CI: 1.48-3.00). CONCLUSIONS: Our findings support the hypothesis that migraine is a midlife risk factor for dementia in later life. The higher rate of dementia in individuals with a hospital-based diagnosis of migraine with aura emphasizes the need for studies on pathological mechanisms and potential preventative measures. Furthermore, given that only hospital-based migraine diagnoses were included in this study, future research should also investigate migraine cases derived from the primary healthcare system to include less severe migraine cases.

Psychosocial job strain and polypharmacy: a national cohort study.

Objectives Psychosocial job strain has been associated with a range of adverse health outcomes. The aim of this study was to examine the association between psychosocial job strain and prospective risk of polypharmacy (the prescription of ≥5 medications) and to evaluate whether coping strategies can modify this risk. Methods Cohort study of 9703 working adults [mean age 47.5 (SD 10.8) years; 54% female] who participated in the Swedish Longitudinal Occupational Survey of Health (SLOSH) at baseline in 2006 or 2008. Psychosocial job strain was represented by job demands and control, and measured by the Swedish version of the demand-control questionnaire. The outcome was incidence of polypharmacy over an eight-year follow-up period. Information on dispensed drugs were extracted from the Swedish Prescribed Drug Register. Logistic regression was used to estimate the association of job strain status with polypharmacy, adjusted for a range of confounders. Results During the follow-up, 1409 people developed polypharmacy (incident rate: 20.6/1000 person-years). In comparison to workers with low-strain jobs (high control/low demands), those with high-strain jobs (low control/high demands) had a significantly higher risk of incident polypharmacy (OR 1.40, 95% CI 1.04-1.89). The impact of high-strain jobs on developing polypharmacy remained among those with covert coping strategies (ie, directed inwards or towards others) but not among those with open coping strategies (ie, primarily directed toward the stressor). Conclusions Workers in high-strain jobs may be at an increased risk of polypharmacy. Open coping strategies may reduce the negative impact of psychosocial job strain on risk of polypharmacy.

Late-life depression and the risk of dementia in 14 countries: a 10-year follow-up study from the Survey of Health, Ageing and Retirement in Europe.

BACKGROUND: Depression is the most common mental health problem and often co-occurs with dementia in old age. This study investigates the influence of late-life depression on risk of dementia. METHODS: A total of 16210 dementia-free participants aged 60+ from the Survey of Health, Aging, and Retirement in Europe were followed up for 10 years to detect incident dementia. Depression was assessed by a 12-item Europe-depression scale, dementia was determined by physician diagnosis reported by the participants and their informants. Fine and Gray model was performed to explore the association between depression and incident dementia taking into account competing risk of death. RESULTS: During an average of 8 years follow-up, 1030 (6.35%) incident dementia were identified. Late-life depression was related to higher subdistribution hazard ratio (sHR) of dementia (sHR=1.52, 95%CI: 1.32-1.75) after adjusting for age, gender, country, education, smoking, drinking, living arrangement, BMI, chronic disease, and physical activity. Further, the risk was only existed in those below age of 80 (sHR=1.75, 95%CI: 1.47-2.07). In addition, a dose-response association was observed between the severity of depression and dementia risk (p for trend<0.001). LIMITATION: The ascertainment of depression and dementia was based on information reported by the participants and/or their informants, which might result in information bias. The causal relationship could not be determined because limited follow-up time. CONCLUSIONS: Late-life depression is associated with higher incidence of dementia in a dose-response fashion. Interventions targeting depression patients aged 60-79 years and those with severe depression may be effective strategies to prevent dementia.