Living alone and risk of dementia: A systematic review and meta-analysis

AimsTo systematically review longitudinal studies on living alone and incident dementia, to pool the results in a meta-analysis and calculate the population risk.MethodsEmbase, Medline and PsycInfo were searched from inception to August 2019 for longitudinal cohort studies of people living alone and risk of dementia. Relative risks (RR) were extracted and effect sizes pooled, with a sensitivity analysis for risk of bias (QUIPS quality rating tool). Population Attributable Fraction (PAF) was calculated, with prevalence of living alone calculated from UK Census data.ResultsTwelve studies were identified for inclusion, nine of which had low risk of bias. The pooled effect size indicated an elevated risk of incident dementia when living alone (all studies RR = 1.30; 95 % CI: 1.15–1.46; low risk of bias studies (RR = 1.31; 95 % CI: 1.13–1.51). The PAF for living alone was 8.9 %.ConclusionsSocial isolation is a more important risk factor for dementia than previously identified, with living alone associated with greater population risk than physical inactivity, hypertension, diabetes and obesity.     

Association of clinical outcome assessments of mobility capacity and incident disability in community-dwelling older adults - a systematic review and meta-analysis

The objective of the present review is to synthesize all available research on the association between mobility capacity and incident disability in non-disabled older adults. MEDLINE, EMBASE and CINAHL databases were searched without any limits or restrictions until February 2021. Published reports of longitudinal cohort studies that estimated a direct association between baseline mobility capacity, assessed with a standardized outcome assessment, and subsequent development of disability, including initially non-disabled older adults were included. The risk of bias was assessed using the Quality in Prognosis Studies (QUIPS) tool. Random-effect models were used to explore the objective. The certainty of evidence was assessed using the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) approach. The main outcome measures were the pooled relative risks (RR) per one conventional unit per mobility assessment for incident disability. A total of 40 reports (85,515 participants at baseline) were included. For usual and fast gait speed, the RR per −0.1 m/s was 1.23 (95% CI: 1.18–1.28; 26,638 participants) and 1.28 (95% CI: 1.19–1.38; 8161 participants), respectively. Each point decrease in Short Physical Performance Battery score increased the risk of incident disability by 30% (RR = 1.30, 95% CI: 1.23–1.38; 9183 participants). The RR of incident disability by each second increase in Timed Up and Go test and Chair Rise Test performance was 1.15 (95% CI: 1.09–1.21; 30,426 participants) and 1.07 (95% CI: 1.04–1.10; 9450 participants), respectively. The review concludes that among community-dwelling non-disabled older adults, poor mobility capacity is a potent modifiable risk factor for incident disability. Mobility impairment should be mandated as a quality indicator of health for older people.     

Depression and risk of sudden cardiac death after acute myocardial infarction: testing for the confounding effects of fatigue

OBJECTIVES: This study examined the impact of depressive symptoms and social support on 2-year sudden cardiac death (SCD) risk, controlling for fatigue symptoms. METHODS: Myocardial infarction (MI) patients (N = 671) participating in the Canadian Amiodarone Myocardial Infarction Arrhythmia Trial completed measures of depression, hostility, and social support. RESULTS: After controlling for significant biological predictors, psychosocial predictors of increased SCD risk in the survival analysis were greater social network contacts (RR = 1.04; 95% CI = 1.01-1.06; p < .007), lower social participation (RR = 0.98; 95% CI = 0.96-1.00; p < .05), and, in placebo-treated patients, elevated depressive symptoms (RR = 2.45; 95% CI = 1.14-5.35; p < .02). Fatigue was associated with SCD (RR = 1.31; 95% CI = 1.11-1.53; p < .001), and, when included in the model, diminished the influence of depression (RR = 1.73; 95% CI = 0.75-3.98; p = .20). When the cognitive-affective depressive symptoms were examined separately from somatic symptoms, there was a trend for an association between cognitive-affective symptoms and SCD in placebo-treated patients after controlling for fatigue (RR = 1.09; 95% CI = 0.99-1.19, p < .06). CONCLUSIONS: Symptoms of depression and fatigue overlap in patients with MI. The trend for the cognitive-affective symptoms of depression to be associated with SCD risk, even after controlling for dyspnea/fatigue, suggests that the association between depression and mortality after AMI cannot be entirely explained as a confound of cardiac-related fatigue. The independent contribution of social participation suggests a role of both depressive symptomatology and social factors in influencing mortality risk after MI.     

Poor adherence to placebo or amiodarone therapy predicts mortality: results from the CAMIAT study. Canadian Amiodarone Myocardial Infarction Arrhythmia Trial.

OBJECTIVE: This study examined the relationship between adherence, mortality, and psychosocial factors. METHODS: Subjects were 1141 patients participating in the Canadian Amiodarone Myocardial Infarction Arrhythmia Trial. Poor adherence to study medication (amiodarone or placebo), measured by pill count over 2 years, was defined as the lower 20th percentile of the pill count distribution. Predictors of adherence were also studied and included demographic and cardiac variables and, in a subset of participants (N = 671), measures of depression, distress, hostility, and social support. RESULTS: In survival analysis controlling for cardiac and demographic variables, poor adherence in the placebo and amiodarone groups was associated with an increased risk of sudden cardiac death (relative risk (RR) = 2.11, 95% confidence interval (CI) = 1.03-4.56, p < .05; and RR = 3.15, 95% CI = 1.34-7.44, p < .01, respectively), total cardiac mortality (RR = 2.04, 95% CI = 1.12-3.72, p < .02; and RR = 2.49, 95% CI = 1.32-4.72, p < .01, respectively), and all-cause mortality (RR = 2.25, 95% CI = 1.27-3.97, p < .001; and RR = 2.34, 95% CI = 1.32-4.17, p < .004, respectively). Logistic regression analysis identified two predictors of poor adherence to placebo: age > 70 years (odds ratio = 2.18, 95% CI = 1.11-4.29, p < .03) and social activities in the month before the index heart attack (odds ratio = 1.02, 95% CI = 1.00-1.04, p < .05). CONCLUSIONS: Poor adherence is associated with a greater risk of mortality. The relationship between adherence and social activities suggests a higher motivation to adhere to treatment in individuals more engaged in enjoyable activities.     

Social media use and parent–child relationship: A cross-sectional study of adolescents

We examined the association between social media use and parent–child relationship quality and tested whether this association is independent of total screen time. Data on 9,732 students (48.4% female) aged 11–20 years were obtained from a provincially representative school-based survey. Heavy use of social media (daily use of more than 2 hr) was associated with greater odds of negative relationships between mother–daughter (odds ratio [OR] = 1.79; 95% confidence interval [CI]: 1.27–2.52), father–daughter (OR = 1.56; 95% CI: 1.16–2.09), father–son (OR = 2.19; 95% CI: 1.58–3.05) but not mother–son (OR = 1.17; 95% CI: 0.88–1.55). Results were similar after further adjusting for total screen time. There were no significant associations between regular use of social media (2 hr or less) and parent–child relationships. These findings suggest that heavy use of social media is associated with negative parent–child relationships. Longitudinal research is necessary to disentangle the pathways between social media use and the parent–child relationship.     

Hot flushes, common symptoms, and social relations among middle-aged nonmenopausal French women in the GAZEL cohort

OBJECTIVE: Many symptoms, including hot flushes (HFs) may appear during the years preceding menopause. Hypotheses to explain these symptoms include biomedical, demographic, and cultural risk factors. Social relations are also associated with various aspects of health. The aim of this study was to analyze the association between social relations and the reporting of HFs and other common symptoms among middle-aged nonmenopausal French women taking into account other factors, including biomedical characteristics. DESIGN: Data came from self-administered questionnaires mailed to 1,180 pre- or perimenopausal women aged 45 to 54 years participating in the French GAZEL cohort. Bivariate and multivariate analyses examined the association between symptoms (HFs, general, psychological, osteoarticular, and breast symptoms) and three scores of social relations (social network, social relations, and satisfaction with social relations). RESULTS: After adjustment, low social support was associated with psychological symptoms (odds ratio [OR] = 2.65; 95% CI: 1.33-5.29) and unsatisfactory social relations were associated with psychological (OR = 2.04; 95% CI: 1.49-2.79) and breast symptoms (OR = 1.38; 95% CI: 1.03-1.84). HFs were not associated with social relations but were related to common symptoms (OR = 2.80; 95% CI: 1.94-4.03). Perimenopausal women were more likely to report HF than premenopausal women (OR = 2.63; 95% CI: 1.88-3.71). CONCLUSION: Social relations were associated with psychological and breast symptoms, but not with HFs. The strong association between common symptoms and HFs suggests that biomedical factors have a greater influence than social relations on the occurrence of HFs.     

Genetic polymorphisms in arginase I and II and childhood asthma and atopy

BACKGROUND: A recent microarray study implicated arginase I (ARG1) and arginase II (ARG2) in mouse allergic asthma models and human asthma. OBJECTIVES: To examine the association between genetic variation in ARG1 and ARG2 and childhood asthma and atopy risk. METHODS: We enrolled 433 case-parent triads, consisting of patients with asthma 4 to 17 years old and their biologic parents, from the allergy clinic of a public hospital in Mexico City between 1998 and 2003. Atopy to 24 aeroallergens was determined by skin prick tests. We genotyped 4 single nucleotide polymorphisms (SNPs) of ARG1 and 4 SNPs of ARG2 with minor allele frequencies higher than 10% by using the TaqMan assay (Roche Molecular Systems, Pleasanton, Calif). RESULTS: ARG1 SNPs and haplotypes were not associated with asthma, but all 4 ARG1 SNPs were associated with the number of positive skin tests (P = .007-.018). Carrying 2 copies of minor alleles for either of 2 highly associated ARG2 SNPs was associated with a statistically significant increased relative risk (RR) of asthma (1.5, 95% CI = 1.1-2.1 for arg2s1; RR = 1.6, 95% CI = 1.1-2.3 for arg2s2). The association was slightly stronger among children with a smoking parent (arg2s1 RR = 2.1, 95% CI = 1.2 - 3.9 with a smoking parent; RR = 1.2, 95% CI = 0.8-1.9 without; interaction P = .025). Haplotype analyses reduced the sample size but supported the single SNP results. One ARG2 SNP was related to the number of positive skin tests (P = .027). CONCLUSION: Variation in arginase genes may contribute to asthma and atopy in children.     

Association of control and risk of severe asthma-related events in severe or difficult-to-treat asthma patients

BACKGROUND: Clinical tools for predicting poor outcomes in asthma patients are lacking. This study investigated the association of asthma control and subsequent severe asthma-related healthcare events in The Epidemiology and Natural History of Asthma: Outcomes and Treatment Regimens (TENOR) study. METHODS: The extent of asthma control problems was determined from baseline values of the Asthma Therapy Assessment Questionnaire (ATAQ). Patients self-reported the presence of severe asthma-related events at 6- and 12-month follow up. Poisson regression models determined the adjusted association between baseline control and the likelihood of severe asthma-related events. RESULTS: At baseline, 2942 patients (mean age, 49.6 years; female, 71.9%) had an ATAQ score (no control problems, 17.0%; 1 control problem, 20.0%; 2 control problems, 30.8%; 3 or 4 control problems, 32.2%) and at least one severe asthma-related event. After adjustment, subjects with three or four control problems were at greater risk for unscheduled office visits [relative risk (RR) = 2.8; 95% confidence interval (CI): 2.4-3.2], course of oral steroids (RR = 2.9; 95% CI: 2.5-3.3), emergency room visits (RR = 4.1; 95% CI: 2.7-6.2) or hospitalization (RR = 13.6; 95% CI: 7.4-24.9), vs no control problems. Progressively poorer levels of asthma control are associated with increasing risk of severe asthma-related events. CONCLUSIONS: This study provides evidence of an association between poor asthma control and future severe asthma-related healthcare events. A validated questionnaire may help clinicians identify patients requiring intervention to prevent future severe asthma-related events.     

Relationship between obesity and structural brain abnormality: Accumulated evidence from observational studies

We aimed to evaluate the relationship between obesity and structural brain abnormalities assessed by magnetic resonance imaging using data from 45 observational epidemiological studies, where five articles reported prospective longitudinal results. In cross-sectional studies’ analyses, the pooled weighted mean difference for total brain volume (TBV) and gray matter volume (GMV) in obese/overweight participants was -11.59 (95 % CI: -23.17 to -0.02) and -10.98 (95 % CI: -20.78 to -1.18), respectively. TBV was adversely associated with BMI and WC, GMV with BMI, and hippocampal volume with BMI, WC, and WHR. WC/WHR are associated with a risk of lacunar and white matter hyperintensity (WMH). In longitudinal studies’ analyses, BMI was not statistically associated with the overall structural brain abnormalities (for continuous BMI: RR = 1.02, 95 % CI: 0.94–1.12; for categorial BMI: RR = 1.18, 95 % CI: 0.75–1.85). Small sample size of prospective longitudinal studies limited the power of its pooled estimates. A higher BMI is associated with lower brain volume while greater WC/WHR, but not BMI, is related to a risk of lacunar infarct and WMH. Future longitudinal research is needed to further elucidate the specific causal relationships and explore preventive measures.     

Association of APOE ε2/ε3/ε4 and promoter gene variants with dementia but not cardiovascular mortality in old age

The common apolipoprotein E (APOE) alleles ε2, ε3, and ε4 are associated with the risk of dementia and cardiovascular disease. Recently, two functional variants (? 219G/T and ?491A/T) were identified in the promoter of the APOE gene that enable a further characterization of the role of the APOE locus in disease. We investigated the contribution of these APOE gene variants to dementia and cardiovascular mortality in old age using a population‐based cohort of 648 subjects aged 85 years and over (Leiden 85‐Plus Study). Genotypes containing an APOE ε4 allele were associated with a 4.1‐fold (95% CI, 2.2–7.7) increased risk of dementia as compared to the ε3/ε3 genotype in old subjects. Moreover, homozygosity for the ?219T allele was found to be associated with a 2.4‐fold (95% CI, 1.0–5.8) increased risk independently of ε2 and ε4; the ?491A/T variant was not associated with dementia. Over a 10‐year follow‐up period, the risk of cardiovascular mortality was not increased among ε4 carriers (RR, 0.6; 95% CI, 0.4–1.0) or ?219T homozygous subjects (RR, 1.1; 95% CI, 0.7–1.7), nor did it decrease among ?491T homozygous subjects (RR, 1.4; 95% CI, 0.6–3.1). In conclusion, both the APOE ε2/ε3/ε4 and the ?219G/T variant were identified as risk factors for dementia but not cardiovascular mortality in old age. Our results support the hypothesis that both the isoform and the amount of APOE may influence the risk of dementia. Furthermore, they emphasize that variation at the APOE locus has a higher impact on the risk of dementia than on the risk of cardiovascular disease in old age. © 2001 Wiley‐Liss, Inc.     

Allergic disorders and risk of depression: A systematic review and meta-analysis of 51 large-scale studies

Background

Previous studies have suggested that allergic disorders are associated with an increased risk of depression. However, the results are conflicting.

Association of kidney function and brain health: A systematic review and meta-analysis of cohort studies

ObjectiveThis study aimed to evaluate the bidirectional association between the kidney dysfunction and the brain health, including structural and functional abnormalities.DesignSystematic review and meta-analysis with network meta-analysis for outcomes with different estimated glomerular filtration rate (eGFR) ranges.Data sourcesPubMed, Embase database, Cochrane library and Web of Science (up to Dec. 2021).Eligibility criteria for selecting studiesLongitudinal studies that provided evidence of the impact of kidney function estimated from eGFR and urine albumin-to-creatinine ratio (UACR) or chronic kidney disease (CKD) on structural and functional brain abnormalities, and those that provided evidence of the opposite relationship. Studies with study population mean age under 18 years old were excluded.Main outcome measuresTwo independent reviewers screened the included studies, extracted the data, and assessed the risk of bias. We performed a random-effects meta-analysis and a network meta-analysis for outcomes with compatible data. We assessed the risk of bias using the Newcastle–Ottawa Quality Assessment Scale criteria (NOS). Subgroup and sensitivity analyses were conducted to explore heterogeneity in the meta-analyses. Inconsistency analyses using the node-splitting method were performed to confirm the results of network meta-analysis.ResultsA total of 53 studies with 3037,357 participants were included in the current systematic review. Among these, 16 provided evidence of structural brain abnormalities, and 38 provided evidence of cognitive impairment and dementia. Analysis of evidence of categorical kidney function showed a positive association between kidney dysfunction and cerebral small vessel disease (cSVD) (relative risk (RR) 1.77, 95% confidence interval (CI) 1.40–2.24, I² = 0.0%), but such results were not found in the analyses of evidence where the kidney function was measured as a continuous variable. Meanwhile, analysis of 28 prior longitudinal studies with 194 compatible sets of data showed that the worse kidney function as categorical variables was related to a greater risk of global brain cognitive disorder (RR 1.28, 95% CI 1.20–1.36, I² = 82.5%).ConclusionsIn this systematic review and meta-analysis, we found a positive association between CKD and functional brain disorders. However, the relationship between the kidney dysfunction and structural abnormalities in the brain remains controversial. As for the opposite relationship, structural brain abnormalities, especially cerebral microbleeds and silent infarction, but not functional brain abnormalities, are associated with worse renal function. In addition, a higher UACR, but not a lower eGFR, was associated with a higher risk of Alzheimer’s disease and vascular dementia.     

Influenza vaccination reduces dementia risk: A systematic review and meta-analysis

Animal models have indicated that influenza vaccination may prevent or delay the onset of dementia. However, the epidemiological evidence in human beings is still limited. Given this background, this systematic review and meta-analysis aimed to summarize the current state of the art of observational studies investigating the association between influenza vaccination and the risk of dementia. We searched Scopus and Pubmed/Medline until 24 September 2021 for studies investigating the risk of dementia by influenza vaccination status. After adjustment for potentially important confounding variables, data were reported as risk ratios (RRs) with 95% confidence intervals (CIs). Among 273 articles initially evaluated, five were included for a total of 292,157 older people free from dementia at baseline (mean age=75.5 ± 7.4 years; 46.8% females). All studies were of high quality. Over a mean follow-up of 9 years, influenza vaccination mitigated the risk of dementia (RR=0.97; 95%CI: 0.94–1.00; I² =99%). This association held after adjustment for a mean of nine potential confounders (RR=0.71; 95%CI: 0.60–0.94; I² =95.9%). In sensitivity analysis, removing one study from the adjusted analyses, the adjusted RR remained similar (RR= 0.67; 95%CI: 0.63–0.70), but the heterogeneity disappears (I² =0%). In conclusion, influenza vaccination was associated with a significantly lower risk of dementia suggesting that the vaccination of older people against influenza may also aid in the prevention of dementia.     

Cardiorespiratory fitness and incident metabolic syndrome in middle-aged Korean men

This study investigated the relationship of cardiorespiratory fitness (CRF) with incident metabolic syndrome in 810 middle aged Korean men. All subjects were free of metabolic syndrome at baseline examination. The metabolic syndrome was defined by NCEP criteria and CRF was directly measured by peak oxygen uptake during a treadmill test. During an average of 3.3 years of follow-up, 155 (19.1%) men developed the metabolic syndrome. The incidence of metabolic syndrome was inversely associated with CRF quartiles (p?相似文献   

Breastfeeding history and childhood allergic status in a prospective birth cohort.

BACKGROUND: Breastfeeding provides the best possible nutrition for newborns, but its role in the development of allergies is complex. OBJECTIVE: To examine the relationship between breastfeeding and early childhood skin sensitization. METHODS: In a birth cohort of 405 children from the Childhood Allergy Study, we used maternal report to classify children's duration of breastfeeding and whether they were breastfed only, formula fed only, or both. We examined the relationships between this information and childhood allergies as determined by skin prick testing for inhalant allergens at age 6 to 7 years. RESULTS: There was no association between duration of breastfeeding and risk of allergic sensitization. Overall, children who were breastfed only were 50% more likely to have allergic sensitization than those fed formula only (relative risk [RR], 1.5; 95% confidence interval [CI], 1.1-2.1). Although the estimates are imprecise, this RR was higher for children born to mothers reporting a history of allergy (RR, 1.8; 95% CI, 1.0-3.0) than for those born to mothers with no allergic history (RR, 1.3; 95% CI, 0.9-2.1), for children in households without (RR, 1.6; 95% CI, 1.1-2.2) vs with (RR, 1.0; 95% CI, 0.3-4.0) multiple pets, and for those with an older sibling (RR, 2.0; 95% CI, 1.2-3.3) vs firstborns (RR, 1.3; 95% CI, 0.8-2.1). CONCLUSIONS: Breastfeeding without formula supplementation may be associated with an increased risk of childhood allergies. However, this association may vary with birth order, exposure to household pets, and maternal allergic history.     

Tuberculosis incidence and mortality in people living with human immunodeficiency virus: a Danish nationwide cohort study

ObjectivesTo explore changes over time in the epidemiology of tuberculosis (TB) in Denmark in people living with human immunodeficiency virus (HIV) (PLWH).MethodsIn this nationwide, population-based cohort study we included all adult PLWH from the Danish HIV Cohort Study (1995–2017) without previous TB. We estimated TB incidence rate (IR), all-cause mortality rate (MR), associated risk and prognostic factors using Poisson regression.ResultsAmong 6982 PLWH (73 596 person-years (PY)), we observed 217 TB events (IR 2.9/1000 PY, 95% CI 2.6–3.4: IR 6.7, 95% CI 5.7–7.9 among migrants and IR 1.4, 95% CI 1.1–1.7 among Danish-born individuals; p < 0.001). The IR of concomitant HIV/TB remained high and unchanged over time. The IR of TB diagnosed >3 months after HIV diagnosis declined with calendar time, longer time from HIV diagnosis, and CD4 cell recovery. Independent TB risk factors were African/Asian/Greenland origin (adjusted incidence rate ratio (aIRR) 5.2, 95% CI 3.5–7.6, aIRR 6.5, 95% CI 4.2–10.0, aIRR 7.0, 95% CI 3.4–14.6, respectively), illicit drug use (aIRR 6.9, 95% CI 4.2–11.2), CD4 <200 cells/μL (aIRR 2.7, 95% CI 2.0–3.6) and not receiving antiretroviral therapy (aIRR 3.7, 95% CI 2.5–5.3). Fifty-five patients died (MR 27.9/1000 PY, 95% CI 21.4–36.3), with no improvement in mortality over time. Mortality prognostic factors were Danish-origin (adjusted mortality rate ratio (aMRR) 2.3, 95% CI 1.3–4.3), social burden (aMRR 3.9, 95% CI 2.2–7.0), CD4 <100 cells/μL at TB diagnosis (aMRR 2.6, 95% CI 1.3–4.9), TB diagnosed >3 months after HIV versus concomitant diagnosis (aMRR 4.3, 95% CI 2.2–8.7) and disseminated TB (aMRR 3.3, 95% CI 1.1–9.9).ConclusionLate HIV presentation with concomitant TB remains a challenge. Declining TB rates in PLWH were observed over time and with CD4 recovery, highlighting the importance of early and successful antiretroviral therapy. However, MR remained high. Our findings highlight the importance of HIV and TB screening strategies and treatment of latent TB in high-risk groups.     

HIV transmission risk among serodiscordant couples: a retrospective study of former plasma donors in Henan, China

OBJECTIVES: To estimate the HIV incidence and assess the behavioral, clinical, and quality-of-life risk factors for HIV transmission among serodiscordant couples from Henan Province, China. METHODS: Between January 2006 and December 2008, initially seronegative spouses were tested for HIV at six month intervals. Retrospectively identified subjects were interviewed through face-to-face questionnaire. Cox proportional-hazards model was used to assess the relationship between risk factors and HIV seroconversion. RESULTS: Out of 1927 couples, 84 (4.3%) seroconversions occurred, representing a seroconversion rate of 1.71 per 100 person-years. Seroconversion rates increased over time. Not always using condoms (RR=8.42; 95% CI, 4.83-14.67), sexual activity ≥ 4 times per month (RR=5.24; 95% CI, 2.55-10.77), not switching anti-retroviral treatment regimen (RR=1.99; 95% CI, 0.85-4.65), and a quality of life score <12 on the psychological domain (RR=2.33; 95% CI, 1.21-4.48) were associated with increased risk of seroconversion. Seventy one percent of index spouses were on ART. There was no association between rate of HIV seroconversion and last recorded CD4 cell count level of the index spouse. CONCLUSIONS: Effective HIV prevention interventions targeting discordant couples should focus on sustaining health education, increasing psychosocial support services, and increasing medication adherence monitoring.     

Is personality associated with dementia risk? A meta-analytic investigation

This study provides a quantitative synthesis of the prospective associations between personality traits (neuroticism, extraversion, openness, agreeableness, conscientiousness) and the risk of incident Alzheimer’s disease and related dementias. We conducted five separate meta-analyses with 8–12 samples (N = 30,036 to 33,054) that were identified through a systematic literature search following the MOOSE guidelines. Higher neuroticism (HR = 1.24, 95% CI [1.17, 1.31]) and lower conscientiousness (HR = 0.77, 95% CI [0.73, 0.81]) were associated with increased dementia risk, even after accounting for covariates such as depressive symptoms. Lower extraversion (HR = 0.92, 95% CI [0.86, 0.97]), openness (HR = 0.91, 95% CI [0.86, 0.96]), and agreeableness (HR = 0.90, 95% CI [0.83, 0.98]) were also associated with increased risk, but these associations were less robust and not significant in fully adjusted models. No evidence of publication bias was found. The strength of associations was unrelated to publication year (i.e., no evidence of winner’s curse). Meta-regressions indicated consistent effects for neuroticism, openness, and conscientiousness across methods to assess dementia, dementia type, follow-up length, sample age, minority, country, and personality measures. The association of extraversion and agreeableness varied by country. Our findings indicate robust associations of neuroticism and conscientiousness with dementia risk.