Citations

INTRODUCTION The cerebral cortex underlies our complex cognitive capabilities. Variations in human cortical surface area and thickness are associated with neurological, psychological, and behavioral traits and can be measured in vivo by magnetic resonance imaging (MRI). Studies in model organisms have identified genes that influence cortical structure, but little is known about common genetic variants that affect human cortical structure. RATIONALE To identify genetic variants associated with human cortical structure at both global and regional levels, we conducted a genome-wide association meta-analysis of brain MRI data from 51,665 individuals across 60 cohorts. We analyzed the surface area and average thickness of the whole cortex and 34 cortical regions with known functional specializations. RESULTS We identified 369 nominally genome-wide significant loci ( P < 5 × 10 −8 ) associated with cortical structure in a discovery sample of 33,992 participants of European ancestry. Of the 360 loci for which replication data were available, 241 loci influencing surface area and 66 influencing thickness remained significant after replication, with 237 loci passing multiple testing correction ( P < 8.3 × 10 −10 ; 187 influencing surface area and 50 influencing thickness). Common genetic variants explained 34% (SE = 3%) of the variation in total surface area and 26% (SE = 2%) in average thickness; surface area and thickness showed a negative genetic correlation ( r G = −0.32, SE = 0.05, P = 6.5 × 10 −12 ), which suggests that genetic influences have opposing effects on surface area and thickness. Bioinformatic analyses showed that total surface area is influenced by genetic variants that alter gene regulatory activity in neural progenitor cells during fetal development. By contrast, average thickness is influenced by active regulatory elements in adult brain samples, which may reflect processes that occur after mid-fetal development, such as myelination, branching, or pruning. When considered together, these results support the radial unit hypothesis that different developmental mechanisms promote surface area expansion and increases in thickness. To identify specific genetic influences on individual cortical regions, we controlled for global measures (total surface area or average thickness) in the regional analyses. After multiple testing correction, we identified 175 loci that influence regional surface area and 46 that influence regional thickness. Loci that affect regional surface area cluster near genes involved in the Wnt signaling pathway, which is known to influence areal identity. We observed significant positive genetic correlations and evidence of bidirectional causation of total surface area with both general cognitive functioning and educational attainment. We found additional positive genetic correlations between total surface area and Parkinson’s disease but did not find evidence of causation. Negative genetic correlations were evident between total surface area and insomnia, attention deficit hyperactivity disorder, depressive symptoms, major depressive disorder, and neuroticism. CONCLUSION This large-scale collaborative work enhances our understanding of the genetic architecture of the human cerebral cortex and its regional patterning. The highly polygenic architecture of the cortex suggests that distinct genes are involved in the development of specific cortical areas. Moreover, we find evidence that brain structure is a key phenotype along the causal pathway that leads from genetic variation to differences in general cognitive function. Identifying genetic influences on human cortical structure. ( A ) Measurement of cortical surface area and thickness from MRI. ( B ) Genomic locations of common genetic variants that influence global and regional cortical structure. ( C ) Our results support the radial unit hypothesis that the expansion of cortical surface area is driven by proliferating neural progenitor cells. ( D ) Cortical surface area shows genetic correlation with psychiatric and cognitive traits. Error bars indicate SE. IMAGE CREDITS: (A) K. COURTNEY; (C) M. R. GLASS

Objective: To understand the interaction of multimorbidity and functional limitations in determining health-care utilization and survival in older adults. Methods: Olmsted County, Minnesota, residents aged 60–89 years in 2005 were categorized into four cohorts based on the presence or absence of multimorbidity (≥3 chronic conditions from a list of 18) and functional limitations (≥1 limitation in an activity of daily living from a list of 9), and were followed through December 31, 2016. Andersen–Gill and Cox regression estimated hazard ratios (HRs) for emergency department (ED) visits, hospitalizations, and death using persons with neither multimorbidity nor functional limitations as the reference (interaction analyses). Results: Among 13,145 persons, 34% had neither multimorbidity nor functional limitations, 44% had multimorbidity only, 4% had functional limitations only, and 18% had both. Over a median follow-up of 11 years, 5906 ED visits, 2654 hospitalizations, and 4559 deaths occurred. Synergistic interactions on an additive scale of multimorbidity and functional limitations were observed for all outcomes; however, the magnitude of the interactions decreased with advancing age. The HR (95% confidence interval) for death among persons with both multimorbidity and functional limitations was 5.34 (4.40–6.47) at age 60–69, 4.16 (3.59–4.83) at age 70–79, and 2.86 (2.45–3.35) at age 80–89 years. Conclusion: The risk of ED visits, hospitalizations, and death among persons with both multimorbidity and functional limitations is greater than additive. The magnitude of the interaction was strongest for the youngest age group, highlighting the importance of interventions to prevent and effectively manage multimorbidity and functional limitations early in life.

Background: In 2012, updated cervical cancer screening recommendations were released with consensus on Papanicolaou (Pap) testing every 3 years for women age 21–65 years or Pap–human papillomavirus (HPV) cotesting at 5-year intervals for women age 30–65 years. Primary study aims: Assess current use of Pap-HPV cotesting and describe local population trends over time in Pap and Pap-HPV cotesting. Secondary aim: Assess sociodemographic factors correlating with screening. Methods: We assessed Rochester Epidemiology Project data for Pap and Pap-HPV cotesting among women age 16 years and older living in Olmsted County, Minnesota, yearly from 2005 (study population n = 47,203) through 2016 (study population n = 49,510). We calculated 3-year (Pap) and 5-year (Pap-HPV) moving prevalence rates of screening as proportion of eligible population. Multivariable logistic regression was used to assess factors potentially associated with screening. Results: In 2016, 64.6% of 27,418 eligible 30- to 65-year-old women were up to date with cervical cancer screening; 60.8% had received Pap-HPV cotest screening. Significant declines in Pap completion rates over time were observed in all age groups, including an unexpected decline in 21- to 29-year-old women. Coincident with decreasing Pap screening rates, Pap-HPV cotesting significantly increased among women age 30–65 years, from 10.0% in 2007 to 60.8% in 2016. Conclusions: This suggests increasing adoption of 2012 screening recommendations in the 30- to 65-year-old population. However, decline in Pap screening among 21- to 29-year-old women is concerning. Disparities by race, ethnicity, smoking status, and comorbidity level were observed. Results suggest need for multilevel patient and clinician interventions to increase cervical cancer screening adherence.

Objective The goal of this study was to identify distinct frailty trajectories (clusters of individuals following a similar progression of frailty over time) in an ageing population and to determine social and behavioural factors associated with frailty trajectories. Design Population-based cohort study. Setting Olmsted County, Minnesota. Participants Olmsted County, Minnesota residents aged 60–89 in 2005. Primary outcome measure Changes in frailty over an 8-year period from 2005 to 2012, measured by constructing a yearly frailty index. Frailty trajectories by decade of age were determined using k-means cluster modelling for longitudinal data. Results After adjustment for age and sex, all social and behavioural factors (education, marital status, living arrangements, smoking status and alcohol use) were significantly associated with frailty trajectories in those aged 60–69 and 70–79 years. After further adjustment for baseline frailty, the likelihood of being in the high frailty trajectory was greatest among those reporting concerns from relatives/friends about alcohol consumption (OR (95% CI) 2.26 (1.19 to 4.29)) and those with less than a high school education (OR (95% CI) 1.98 (1.32 to 2.96)) in the 60–69 year olds. In the 70–79 year olds, the largest associations were observed among those with concerns from oneself about alcohol consumption (OR (95% CI) 1.92 (1.23 to 3.00)), those with less than a high school education (OR (95% CI) 1.57 (1.12 to 2.22)), and those living with family (vs spouse; OR (95% CI) 1.76 (1.05 to 2.94)). No factors remained associated with frailty trajectories in the 80–89 year olds after adjustment for baseline frailty. Conclusions Social and behavioural factors are associated with frailty, with stronger associations observed in younger ages. Recognition of social and behavioural factors associated with increasing frailty may inform interventions for individuals at risk of worsening frailty, specifically when targeted at younger individuals.

Objectives To identify distinct frailty trajectories (clusters of individuals following a similar progression of frailty over time) in an aging population and to estimate associations between frailty trajectories and emergency department visits, hospitalizations, and all‐cause mortality. Design Population‐based cohort study. Setting Olmsted County, Minnesota. Participants Olmsted County, Minnesota residents aged 60–89 in 2005. Measurements Longitudinal changes in frailty between 2005 and 2012 were measured by constructing a yearly Rockwood frailty index incorporating body mass index, 17 comorbidities, and 14 activities of daily living. The frailty index measures variation in health status as the proportion of deficits present of the 32 considered (range 0–1). Results Of the 16,443 Olmsted County residents aged 60–89 in 2005, 12,270 (74.6%) had at least 3 years of frailty index measures and were retained for analysis. The median baseline frailty index increased with age (0.11 for 60–69, 0.14 for 70–79, 0.19 for 80–89). Three distinct frailty trajectories were identified in individuals aged 60–69 at baseline and two trajectories in those aged 70–79 and 80–89. Within each decade of age, increasing frailty trajectories were associated with greater risks of emergency department visits, hospitalization, and all‐cause mortality, even after adjustment for baseline frailty index. Conclusion The number of frailty trajectories differed according to age. Within each age group, those in the highest frailty trajectory had greater healthcare use and worse survival. Frailty trajectories may offer a way to target aging individuals at high risk of hospitalization or death for therapeutic or preventive interventions.

The evolution of metabolic and cardiovascular disease (CVD) complications after liver transplantation (LT) is poorly characterized. We aim to illustrate the prevalence of obesity and metabolic syndrome (MS), define the cumulative incidence of CVD, and characterize risk factors associated with these comorbidities after LT. A retrospective review of 455 consecutive LT recipients from 1999 to 2004 with an 8‐ to 12‐year follow‐up was performed. Obesity increased from 23.8% (4 months) to 40.8% (3 years) after LT. Increase in body mass index predicted MS at 1 year after LT (odds ratio, 1.1; P < 0.001, per point). CVD developed in 10.6%, 20.7%, and 30.3% of recipients within 1, 5, and 8 years, respectively. Age, diabetes, hypertension, glomerular filtration rate < 60 mL/minute, prior CVD, ejection fraction < 60%, left ventricular hypertrophy, and serum troponin (TN) > 0.07 ng/mL were associated with CVD on univariate analysis. Age (hazard ratio [HR], 1.03; 95% confidence interval [CI], 1.01‐1.06; P = 0.019), diabetes (HR, 1.78; 95% CI, 1.09‐2.92; P = 0.022), prior history of CVD (HR, 2.46; 95% CI, 1.45‐4.16; P < 0.001), and serum TN > 0.07 ng/mL (HR, 1.98; 95% CI, 1.23‐3.18; P = 0.005) were independently associated with CVD in the long term. Smoking history (ever), sex, hyperlipidemia, and serum ferritin levels were not predictive of CVD. Tacrolimus use versus noncalcineurin‐based immunosuppression (HR, 0.26; 95% CI, 0.14‐0.49; P < 0.001) was associated with reduced risk of CVD but not versus cyclosporine (HR, 0.67; 95% CI, 0.30‐1.49; P = 0.322). CVD is common after LT. Independent of MS, more data are needed to identify nonconventional risk factors and biomarkers like serum TN. Curbing weight gain in the early months after transplant may impact MS and subsequent CVD in the long term. Liver Transpl 21:889‐896, 2015. © 2015 AASLD.

AbstractBackground & AimsChronic kidney disease (CKD) after liver transplant (LT) is associated with increased long‐term mortality. The impact of gender on CKD before and after LT is unknown. To further define risk factors and analyse gender differences in the incidence and progression of CKD after liver transplant.MethodsFour hundred and fifty‐five consecutive adult primary solitary LT recipients were included. Iothalamate clearance tests performed over time were analysed.ResultsMean age was 51.4 ± 10.4 years with 63% males. A percentage of 29.1% of females and 21.1% of males had a GFR<60 ml/min/1.73 m2 and 10.2% of females and 5.9% of males had GFR<30 ml/min/1.73 m2 prior to transplant. At 1 year, 52.6% of recipients tested (69.6% females, 43.0% males) had GFR<60 ml/min/1.73 m2 and 7.3% (11.6% females, 4.9% males) had GFR<30 ml/min/1.73 m2. Pre‐LT GFR<60 ml/min/1.73 m2 [OR 3.28, (1.76–6.10), P ≤ 0.001], female gender (OR 2.96, (1.72–5.10), P < 0.001) and age [OR 1.09, (1.05–1.12), P < 0.001] were independently predictive of stage ≥3 CKD at 1 year post‐LT. Female gender [OR 2.52, (1.25–4.71), P = 0.004], age [OR 1.05, (1.02–1.08), P = 0.003] and NASH [OR 2.95, (1.06–8.21), P = 0.039] were independently predictive of ≥stage 3 CKD at 5 years post‐LT. Pre‐LT diabetes was associated with stage 4 CKD at 5 years [OR 2.91, (1.33–6.36), P = 0.008] post‐LT.ConclusionsIn addition to age and pre‐LT CKD, female gender and NASH are independent predictors of ≥stage 3 CKD post‐LT. Gender‐based approaches to optimize modifiable risk factors are needed to improved post‐transplant renal function.