Yuri Milaneschi

Understanding the somatic consequences of depression: biological mechanisms and the role of depression symptom profile

Depression is the most common psychiatric disorder worldwide. The burden of disease for depression goes beyond functioning and quality of life and extends to somatic health. Depression has been shown to subsequently increase the risk of, for example, cardiovascular, stroke, diabetes and obesity morbidity. These somatic consequences could partly be due to metabolic, immuno-inflammatory, autonomic and hypothalamic-pituitary-adrenal (HPA)-axis dysregulations which have been suggested to be more often present among depressed patients. Evidence linking depression to metabolic syndrome abnormalities indicates that depression is especially associated with its obesity-related components (for example, abdominal obesity and dyslipidemia). In addition, systemic inflammation and hyperactivity of the HPA-axis have been consistently observed among depressed patients. Slightly less consistent observations are for autonomic dysregulation among depressed patients. The heterogeneity of the depression concept seems to play a differentiating role: metabolic syndrome and inflammation up-regulations appear more specific to the atypical depression subtype, whereas hypercortisolemia appears more specific for melancholic depression. This review finishes with potential treatment implications for the downward spiral in which different depressive symptom profiles and biological dysregulations may impact on each other and interact with somatic health decline.

A Higher Adherence to a Mediterranean-Style Diet Is Inversely Associated with the Development of Frailty in Community-Dwelling Elderly Men and Women

Adherence to a Mediterranean-style diet is associated with a lower risk for mortality, cognitive decline, and dementia. Whether adherence to a Mediterranean-style diet protects against age-related frailty is unclear. Therefore, our objective was to examine the association between a Mediterranean-style diet with the risk of frailty in community-dwelling older persons. We conducted longitudinal analyses using data from 690 community-living persons (≥65 y) who were randomly selected from a population registry in Tuscany, Italy. Participants of the Invecchiare in Chianti study of aging completed the baseline examination in 1998-2000 and were re-examined at least once over 6 y. Adherence to a Mediterranean-style diet (scored 0-9, modeled categorically as ≤3, 4-5, and ≥6) was computed from the European Prospective Investigation into Cancer and nutrition FFQ previously validated in this cohort. Frailty was defined as having at least 2 of the following criteria: poor muscle strength, feeling of exhaustion, low walking speed, and low physical activity. After a 6-y follow-up, higher adherence (score ≥6) to a Mediterranean-style diet was associated with lower odds of developing frailty [OR = 0.30 (95% CI: 0.14, 0.66)] compared with those with lower adherence (score ≤3). A higher adherence to a Mediterranean-style diet at baseline was also associated with a lower risk of low physical activity (OR = 0.62; 95% CI: 0.40, 0.96) and low walking speed [OR = 0.48 (95% CI: 0.27, 0.86)] but not with feelings of exhaustion and poor muscle strength. In community-dwelling older adults, higher adherence to a Mediterranean-style diet was inversely associated with the development of frailty.

Interleukin-1 receptor antagonist and incident depressive symptoms over 6 years in older persons: the InCHIANTI study

BACKGROUND We test the hypothesis that in older persons higher plasma levels of inflammatory markers predict the development of depressive symptoms during a 6-year follow-up. METHOD This study is part of the InCHIANTI (Invecchiare in Chianti, aging in the Chianti area) study, a prospective population-based study of older persons. The sample consisted of 991 participants, ages 65 years and older. Serum levels of C-reactive protein, interleukin (IL)-1beta, IL-1 receptor antagonist (ra), tumor necrosis factor-alpha, IL-6, IL-6 receptor, and IL-18 were measured. Depressive symptoms were assessed at baseline and at the 3- and 6-year follow-ups with the Center for Epidemiological Studies-Depression Scale (CES-D). Depressed mood was defined as CES-D > 20. Potential confounders were baseline variables related to sociodemographic, somatic health, and functional status. RESULTS At baseline, IL-1ra levels were significantly higher (p = .004) in depressed compared with nondepressed participants. After adjustment for confounders, among subjects free of depression at baseline, those in the third and fourth IL-1ra quartiles compared with those in the lowest quartile had, respectively, a 2.32-fold (95% confidence interval: 1.21-4.42, p = .01) and 2.78-fold (95% confidence interval: 1.47-5.26, p = .002) higher risk of developing depressed mood during a 6-year follow-up. CONCLUSIONS In old age, persons with high plasma levels of IL1-ra had a higher risk of developing depressive symptoms over time. These findings suggest a potential causal role for inflammation in the development of depressive symptoms in older persons.

The trajectory of depressive symptoms across the adult life span.

IMPORTANCE Long-term longitudinal studies are needed to delineate the trajectory of depressive symptoms across adulthood and to individuate factors that may contribute to increases in depressive symptoms in older adulthood. OBJECTIVES To estimate the trajectory of depressive symptoms across the adult life span; to test whether this trajectory varies by demographic factors (sex, ethnicity, and educational level) and antidepressant medication use; and to test whether disease burden, functional limitations, and proximity to death explain the increase in depressive symptoms in old age. DESIGN Longitudinal study. SETTING Community. PARTICIPANTS The study included 2320 participants (47.0% female; mean [SD] age at baseline, 58.1 [17.0] years; range, 19-95 years) from the Baltimore Longitudinal Study of Aging. MAIN OUTCOMES AND MEASURES Estimated trajectory of depressive symptoms modeled from 10, 982 assessments (mean [SD] assessments per participant, 4.7 [3.6]; range, 1-21) based on the Center for Epidemiologic Studies Depression scale and 3 subscales (depressed affect, somatic complaints, and interpersonal problems). RESULTS The linear (γ10 = 0.52; P < .01) and quadratic (γ20 = 0.43; P < .01) terms were significant, which indicated that depressive symptoms were highest in young adulthood, decreased across middle adulthood, and increased again in older adulthood. The subscales followed a similar pattern. Women reported more depressed affect at younger ages, but an interaction with age suggested that this gap disappeared in old age. Accounting for comorbidity, functional limitations, and impending death slightly reduced but did not eliminate the uptick in depressive symptoms in old age. CONCLUSIONS AND RELEVANCE Symptoms of depression follow a U-shaped pattern across adulthood. Older adults experience an increase in distress that is not due solely to declines in physical health or approaching death.

A genome-wide association study of aging

Human longevity and healthy aging show moderate heritability (20%-50%). We conducted a meta-analysis of genome-wide association studies from 9 studies from the Cohorts for Heart and Aging Research in Genomic Epidemiology Consortium for 2 outcomes: (1) all-cause mortality, and (2) survival free of major disease or death. No single nucleotide polymorphism (SNP) was a genome-wide significant predictor of either outcome (p < 5 × 10(-8)). We found 14 independent SNPs that predicted risk of death, and 8 SNPs that predicted event-free survival (p < 10(-5)). These SNPs are in or near genes that are highly expressed in the brain (HECW2, HIP1, BIN2, GRIA1), genes involved in neural development and function (KCNQ4, LMO4, GRIA1, NETO1) and autophagy (ATG4C), and genes that are associated with risk of various diseases including cancer and Alzheimers disease. In addition to considerable overlap between the traits, pathway and network analysis corroborated these findings. These findings indicate that variation in genes involved in neurological processes may be an important factor in regulating aging free of major disease and achieving longevity.

Urinary cortisol and six-year risk of all-cause and cardiovascular mortality

CONTEXT The stress hormone cortisol has been linked with unfavorable cardiovascular risk factors, but longitudinal studies examining whether high levels of cortisol predict cardiovascular mortality are largely absent. OBJECTIVE The aim of this study was to examine whether urinary cortisol levels predict all-cause and cardiovascular mortality over 6 yr of follow-up in a general population of older persons. DESIGN AND SETTING Participants were part of the InCHIANTI study, a prospective cohort study in the older general population with 6 yr of follow-up. PARTICIPANTS We studied 861 participants aged 65 yr and older. MAIN OUTCOME MEASURE Twenty-four-hour urinary cortisol levels were assessed at baseline. In the following 6 yr, all-cause and cardiovascular mortality was ascertained from death certificates. Cardiovascular mortality included deaths due to ischemic heart disease and cerebrovascular disease. RESULTS During a mean follow-up of 5.7 (sd = 1.2) yr, 183 persons died, of whom 41 died from cardiovascular disease. After adjustment for sociodemographics, health indicators, and baseline cardiovascular disease, urinary cortisol did not increase the risk of noncardiovascular mortality, but it did increase cardiovascular mortality risk. Persons in the highest tertile of urinary cortisol had a five times increased risk of dying of cardiovascular disease (hazard ratio = 5.00; 95% confidence interval = 2.02-12.37). This effect was found to be consistent across persons with and without cardiovascular disease at baseline (p interaction = 0.78). CONCLUSIONS High cortisol levels strongly predict cardiovascular death among persons both with and without preexisting cardiovascular disease. The specific link with cardiovascular mortality, and not other causes of mortality, suggests that high cortisol levels might be particularly damaging to the cardiovascular system.

Genome-Wide Meta-Analysis for Serum Calcium Identifies Significantly Associated SNPs near the Calcium-Sensing Receptor (CASR) Gene

Calcium has a pivotal role in biological functions, and serum calcium levels have been associated with numerous disorders of bone and mineral metabolism, as well as with cardiovascular mortality. Here we report results from a genome-wide association study of serum calcium, integrating data from four independent cohorts including a total of 12,865 individuals of European and Indian Asian descent. Our meta-analysis shows that serum calcium is associated with SNPs in or near the calcium-sensing receptor (CASR) gene on 3q13. The top hit with a p-value of 6.3×10-37 is rs1801725, a missense variant, explaining 1.26% of the variance in serum calcium. This SNP had the strongest association in individuals of European descent, while for individuals of Indian Asian descent the top hit was rs17251221 (p = 1.1×10-21), a SNP in strong linkage disequilibrium with rs1801725. The strongest locus in CASR was shown to replicate in an independent Icelandic cohort of 4,126 individuals (p = 1.02×10-4). This genome-wide meta-analysis shows that common CASR variants modulate serum calcium levels in the adult general population, which confirms previous results in some candidate gene studies of the CASR locus. This study highlights the key role of CASR in calcium regulation.

Risk factors for disability in older persons over 3-year follow-up

BACKGROUND the identification of modifiable risk factors for preventing disability in older individuals is essential for planning preventive strategies. PURPOSE to identify cross-sectional correlates of disability and risk factors for the development activities of daily living (ADL) and instrumental ADL (IADL) disability in community-dwelling older adults. METHODS the study population consisted of 897 subjects aged 65-102 years from the InCHIANTI study, a population-based cohort in Tuscany (Italy). Factors potentially associated with high risk of disability were measured at baseline (1998-2000), and disability in ADLs and IADLs were assessed both at baseline and at the 3-year follow-up (2001-03). RESULTS the baseline prevalence of ADL disability and IADL disability were, respectively, 5.5% (49/897) and 22.2% (199/897). Of 848 participants free of ADL disability at baseline, 72 developed ADL disability and 25 of the 49 who were already disabled had a worsening in ADL disability over a 3-year follow-up. Of 698 participants without IADL disability at baseline, 100 developed IADL disability and 104 of the 199 who already had IADL disability had a worsening disability in IADL over 3 years. In a fully adjusted model, high level of physical activity compared to sedentary state was significantly associated with lower incidence rates of both ADL and IADL disability at the 3-year follow-up visit (odds ratio (OR): 0.30; 95% confidence intervals (CI) 0.12-0.76 for ADL disability and OR: 0.18; 95% CI 0.09-0.36 for IADL disability). After adjusting for multiple confounders, higher energy intake (OR for difference in 100 kcal/day: 1.09; 95% CI 1.02-1.15) and hypertension (OR: 1.91; 95% CI 1.06-3.43) were significant risk factors for incident or worsening ADL disability. CONCLUSIONS higher level of physical activity and lower energy intake may be protective against the development in ADL and IADL disability in older persons.

Mediterranean diet and mobility decline in older persons.

We examined whether adherence to a Mediterranean-style diet has positive effects on mobility assessed over a 9-year follow-up in a representative sample of older adults. This research is part of the InCHIANTI Study, a prospective population-based study of older persons in Tuscany, Italy. The sample for this analysis included 935 women and men aged 65 years and older. Adherence to the Mediterranean diet was assessed at baseline by the standard 10-unit Mediterranean diet score (MDS). Lower extremity function was measured at baseline, and at the 3-, 6- and 9-year follow-up visits using the short physical performance battery (SPPB). At baseline, higher adherence to Mediterranean diet was associated with better lower body performance. Participants with higher adherence experienced less decline in SPPB score, which was of 0.9 points higher (p<.0001) at the 3-year-follow, 1.1 points higher (p=0.0004) at the 6-year follow-up and 0.9 points higher (p=0.04) at the 9-year follow-up compared to those with lower adherence. Among participants free of mobility disability at baseline, those with higher adherence had a lower risk (HR=0.71, 95% CI=0.51-0.98, p=0.04) of developing new mobility disability. High adherence to a Mediterranean-style diet is associated with a slower decline of mobility over time in community-dwelling older persons. If replicated, this observation is highly relevant in terms of public health.

Genetic studies of major depressive disorder: why are there no genome-wide association study findings and what can we do about it?

Over the past 5 years, the genome-wide association study (GWAS) method has produced significant findings that are providing insights into the biological pathways involved in disease susceptibility for both schizophrenia and bipolar disorder. Yet, we have no such findings for major depressive disorder (MDD) (1)—the most common of these disorders, causing the greatest disability in the world population. We were asked by the editor of this journal to comment on why progress has been so difficult for MDD and how we can do better. Consider, by contrast, the remarkable GWAS results achieved for schizophrenia (2). First, some background: GWAS arrays assay common single nucleotide polymorphisms (SNPs) and copy number variants (CNVs). (Strong associations have been observed between rare CNVs and schizophrenia but not mood disorders, with larger analyses of the latter now underway. Thus, CNVs are not considered further here.) Common SNPs are variations at one nucleic acid position in 5% or more of chromosomes in a population—a frequency achieved, over thousands of generations, by variants that are typically neutral with respect to survival and have small or no effects on serious disease. GWAS arrays of 250,000 to 1,000,000 tag SNPs capture most of the effects of common SNPs on diseases or traits, because each genotyped SNP is strongly correlated with many nearby SNPs. The statistical power to identify significant association depends on the effect size of each SNP and the sample size. Figure 1 illustrates the relationship between the number of cases studied (plus adequate control subjects) and the number of significant independent associations for several disorders or traits. (By independent, we mean that a region with significant association to a set of intercorrelated SNPs is counted only once.) For schizophrenia, analyses of multiple GWAS datasets by the