Leg length, skull circumference, and the incidence of dementia in Latin America and China: A 10/66 population-based cohort study

Cross-diagnostic evaluation of minor physical anomalies in psychiatric disorders

BACKGROUND

Minor physical anomalies (MPA) are markers of impaired neurodevelopment during the prenatal stage. Assessing MPA across psychiatric disorders may help understand their shared nature. In addition, MPA in family members would indicate a shared liability and endophenotype potential. We examined familial aggregation of MPA and their role as transdiagnostic and disorder-specific markers of 5 major psychiatric/neuropsychiatric conditions (schizophrenia, bipolar disorder, substance dependence, obsessive-compulsive disorder, and Alzheimer's dementia).

METHODS

Modified Waldrop's MPA scale was applied on 1321 individuals from 439 transdiagnostic multiplex families and 125 healthy population controls (HC). Stage of fetal development (morphogenetic/phenogenetic)- and anatomical location (craniofacial/peripheral)-based sub-scores were calculated. Familiality and endophenotypic potential of MPA were analyzed with serial negative binomial mixed-effect regression. Cross-diagnostic differences and the effect of family history density (FHD) of each diagnosis on MPA were assessed. Mixed-effects Cox models estimated the influence of MPA on age-at-onset of illness (AAO).

RESULTS

MPA were found to be heritable in families with psychiatric disorders, with a familiality of 0.52. MPA were higher in psychotic disorders after controlling for effects of sex and intrafamilial correlation. Morphogenetic variant MPA was noted to be lower in dementia in comparison to HC. FHD of schizophrenia and bipolar disorder predicted higher, and that of dementia and substance dependence predicted lower MPA. MPA brought forward the AAO [HR:1.07 (1.03-1.11)], and this was more apparent in psychotic disorders.

CONCLUSION

MPA are transmissible in families, are specifically related to the risk of developing psychoses, and predict an earlier age at onset. Neurodevelopmentally informed classification of MPA has the potential to enhance the etiopathogenic and translational understanding of psychiatric disorders.

Associations between Depression, Depressive Symptoms, and Incidence of Dementia in Latin America: A 10/66 Dementia Research Group Study

BACKGROUND

A growing body of evidence suggests that depression is related to dementia in older adults. Previous research has been done in high-income countries and there is a lack of studies in low- and middle income countries (LMICs).

OBJECTIVE

To examine the relationship between depressive symptoms and incidence of dementia in a population-based study of older adults in Latin America.

METHODS

The study is a part of the 10/66 Dementia Research Group's population survey and includes 11,472 older adults (baseline mean age 74 years) from Cuba, Dominican Republic, Mexico, Peru, Puerto Rico, and Venezuela. The baseline examinations were done in 2003-2007 and the follow-up examinations 4 years later. Semi-structured psychiatric interviews gave information about ICD-10 depression and sub-syndromal depression (i.e., ≥4 depressive symptoms) at baseline. Information on dementia were collected at the follow-up examination. Competing risk models analyzed the associations between depression and incidence of dementia and the final model were adjusted for age, sex, education, stroke, and diabetes. Separate analyses were conducted for each site and then meta-analyzed by means of fixed effect models.

RESULTS

At baseline, the prevalence of depression was 26.0% (n = 2,980): 5.4% had ICD-10 depression and 20.6% sub-syndromal depression. During the follow-up period, 9.3% (n = 862) developed dementia and 14.3% (n = 1,329) deceased. In the pooled analyses, both ICD-10 depression (adjusted sub-hazard ratio (sHR) 1.63, 95% confidence interval (CI) 1.26-2.11) and sub-syndromal depression (adjusted sHR 1.28, 95% CI: 1.09-1.51) were associated with increased incidence of dementia. The Higging I2 tests showed a moderate heterogeneity across the study sites.

CONCLUSION

Our findings suggest that late-life depression is associated with the incidence of dementia in LMICs in Latin America, which support results from earlier studies conducted in high-income countries.

Short height and poor education increase the risk of dementia in Nigerian type 2 diabetic women

Introduction

There is urgent need to investigate type 2 diabetes and dementia crosstalk in sub-Saharan African countries with special attention to women who have higher vulnerability. Nigeria which has the highest number of diabetics on the African continent is a good location for the investigation.

Methods

Biophysical parameters, occupation, education, burden of diabetes mellitus, cardiovascular health, and cognition were evaluated in 102 type 2 diabetics and 99 controls.

Results

Short physical stature and lower level of education were hallmarks of diabetes in females. Two dementia scales (Mini–Mental State Examination and six-item Cognitive Impairment Test) showed cognitive impairment status, with the six-item Cognitive Impairment Test scale being more specific and sensitive. Both scales showed correlations with age, education, weight, height, and disease onset, whereas fasten blood glucose was negatively correlated with height and their blood pressure was normal.

Discussion

Height, an easy-to-measure parameter in Nigeria, may reveal increased risk of dementia in poorly educated female Nigerian diabetics, thus helping to improve preventive and therapeutic interventions.