Severe heart failure in a unique case of cobalamin-C-deficiency resolved with LVAD implantation and subsequent heart transplantation.

Introduction Cobalamin c deficiency (cblC), an inborn error of vitamin B12 metabolism, is caused by mutations of the MMACHC gene. It usually leads to a multisystemic disease; 50% of all patients with cblC have various structural heart defects. Severe congestive heart failure (HF) may also occur and its prognosis is poorly documented. Case report We present the case of a young man who had been diagnosed with cblC due to C331T mutation in the MMACHC gene at the age of 3 days and had been treated with substitution therapy (OH-Cbl, mecobalamine, carnitine, betaine, and calcium folinate) since then. He had mildly impaired cognitive function; an ectopic hypophysis/pituitary insufficiency, with adequate hormone replacement therapy; obstructive sleep apnea syndrome, treated with CPAP, bronchial asthma, and obesity (BMI of 30). The liver and kidney functions were normal. He developed severe dilated cardiomyopathy and HF at the age of 12y. With medical treatment, his condition improved and he was stable (NYHA class II) for several years. Six years later, his status deteriorated rapidly, as he developed advanced HF, INTERMACS 3. The cardiac ultrasound revealed dilated ventricles with severely depressed ejection fraction (EF), increased filling pressures, and pulmonary hypertension (sPAP 60 mmHg). Cardiac MRI showed extremely dilated chambers (LVedv 609 mL, RVedv 398 mL) with pronounced non-compaction, and a left ventricle EF of 13%. A primary prophylactic ICD and a left ventricular assist device (LVAD/HM3) were implanted, and the patient was subsequently listed for heart transplantation (HTx). After 25 months on the waiting list, he underwent an uncomplicated HTx. However postoperatively, he got two episodes of cardiac tamponade, as well as mediastinitis, treated with antibiotics and vaccum assisted closure. He developed severe kidney failure, which fully recovered after two months, and was treated successfully for an early moderate allograft rejection (ISHT 2). At the latest outward visit, twelve months after HTx, the patient was doing excellent. Summary To the best of our knowledge, this is the first ever reported case of a patient with CblC undergoing an LVAD implantation and subsequently a HTx. Although both interventions were complicated with bleeding events, this seems to be a treatment option for advanced HF in patients with CblC.

Snyder-Robinson syndrome presenting with learning disability, epilepsy, and osteoporosis: a novel SMS gene variant.

Snyder-Robinson syndrome (SRS) is a rare X-linked recessive disorder characterized by a collection of clinical features including mild to severe intellectual disability, hypertonia, marfanoid habitus, facial asymmetry, osteoporosis, developmental delay and seizures. Whole genome sequencing (WGS) identified a mutation in the spermine synthase (SMS) gene (c.746 A>G, p.Tyr249Cys) in a male with kyphosis, seizures, and osteoporosis. His phenotype is unique in that he does not have intellectual disability (ID) but does have a mild learning disability. This case demonstrates a milder presentation of SRS and expands the phenotype beyond the reported literature.

Lipodystrophy in methylmalonic acidemia associated with elevated FGF21 and abnormal methylmalonylation.

A distinct adipose tissue distribution pattern was observed in patients with methylmalonyl-CoA mutase deficiency, an inborn error of branched-chain amino acid (BCAA) metabolism, characterized by centripetal obesity with proximal upper and lower extremity fat deposition and paucity of visceral fat, that resembles familial multiple lipomatosis syndrome. To explore brown and white fat physiology in methylmalonic acidemia (MMA), body composition, adipokines, and inflammatory markers were assessed in 46 patients with MMA and 99 matched controls. Fibroblast growth factor 21 levels were associated with acyl-CoA accretion, aberrant methylmalonylation in adipose tissue, and an attenuated inflammatory cytokine profile. In parallel, brown and white fat were examined in a liver-specific transgenic MMA mouse model (Mmut-/- TgINS-Alb-Mmut). The MMA mice exhibited abnormal nonshivering thermogenesis with whitened brown fat and had an ineffective transcriptional response to cold stress. Treatment of the MMA mice with bezafibrates led to clinical improvement with beiging of subcutaneous fat depots, which resembled the distribution seen in the patients. These studies defined what we believe to be a novel lipodystrophy phenotype in patients with defects in the terminal steps of BCAA oxidation and demonstrated that beiging of subcutaneous adipose tissue in MMA could readily be induced with small molecules.

Intellectual disability and autism in propionic acidemia: a biomarker-behavioral investigation implicating dysregulated mitochondrial biology.

Propionic acidemia (PA) is an autosomal recessive condition (OMIM #606054), wherein pathogenic variants in PCCA and PCCB impair the activity of propionyl-CoA carboxylase. PA is associated with neurodevelopmental disorders, including intellectual disability (ID) and autism spectrum disorder (ASD); however, the correlates and mechanisms of these outcomes remain unknown. Using data from a subset of participants with PA enrolled in a dedicated natural history study (n = 33), we explored associations between neurodevelopmental phenotypes and laboratory parameters. Twenty (61%) participants received an ID diagnosis, and 12 of the 31 (39%) who were fully evaluated received the diagnosis of ASD. A diagnosis of ID, lower full-scale IQ (sample mean = 65 ± 26), and lower adaptive behavior composite scores (sample mean = 67 ± 23) were associated with several biomarkers. Higher concentrations of plasma propionylcarnitine, plasma total 2-methylcitrate, serum erythropoietin, and mitochondrial biomarkers plasma FGF21 and GDF15 were associated with a more severe ID profile. Reduced 1-13C-propionate oxidative capacity and decreased levels of plasma and urinary glutamine were also associated with a more severe ID profile. Only two parameters, increased serum erythropoietin and decreased plasma glutamine, were associated with ASD. Plasma glycine, one of the defining features of PA, was not meaningfully associated with either ID or ASD. Thus, while both ID and ASD were commonly observed in our PA cohort, only ID was robustly associated with metabolic parameters. Our results suggest that disease severity and associated mitochondrial dysfunction may play a role in CNS complications of PA and identify potential biomarkers and candidate surrogate endpoints.

Systemic gene therapy using an AAV44.9 vector rescues a neonatal lethal mouse model of propionic acidemia.

Propionic acidemia (PA) is rare autosomal recessive metabolic disorder caused by defects in the mitochondrially localized enzyme propionyl-coenzyme A (CoA) carboxylase. Patients with PA can suffer from lethal metabolic decompensation and cardiomyopathy despite current medical management, which has led to the pursuit of gene therapy as a new treatment option for patients. Here we assess the therapeutic efficacy of a recently described adeno-associated virus (AAV) capsid, AAV44.9, to deliver a therapeutic PCCA transgene in a new mouse model of propionyl-CoA carboxylase α (PCCA) deficiency generated by genome editing. Pcca-/- mice recapitulate the severe neonatal presentation of PA and manifest uniform neonatal lethality, absent PCCA expression, and increased 2-methylcitrate. A single injection of the AAV44.9 PCCA vector in the immediate newborn period, systemically delivered at a dose of 1e11 vector genome (vg)/pup but not 1e10 vg/pup, increased survival, reduced plasma methylcitrate, and resulted in high levels of transgene expression in the liver and heart in treated Pcca-/- mice. Our studies not only establish a versatile and accurate new mouse model of PA but further demonstrate that the AAV44.9 vectors may be suitable for treatment of many metabolic disorders where hepato-cardiac transduction following systemic delivery is desired, such as PA, and, by extension, fatty acid oxidation defects and glycogen storage disorders.

Biomarkers to predict disease progression and therapeutic response in isolated methylmalonic acidemia.

Methylmalonic Acidemia (MMA) is a heterogenous group of inborn errors of metabolism caused by a defect in the methylmalonyl-CoA mutase (MMUT) enzyme or the synthesis and transport of its cofactor, 5'-deoxy-adenosylcobalamin. It is characterized by life-threatening episodes of ketoacidosis, chronic kidney disease, and other multiorgan complications. Liver transplantation can improve patient stability and survival and thus provides clinical and biochemical benchmarks for the development of hepatocyte-targeted genomic therapies. Data are presented from a US natural history protocol that evaluated subjects with different types of MMA including mut-type (N = 91), cblB-type (15), and cblA-type MMA (17), as well as from an Italian cohort of mut-type (N = 19) and cblB-type MMA (N = 2) subjects, including data before and after organ transplantation in both cohorts. Canonical metabolic markers, such as serum methylmalonic acid and propionylcarnitine, are variable and affected by dietary intake and renal function. We have therefore explored the use of the 1-13 C-propionate oxidation breath test (POBT) to measure metabolic capacity and the changes in circulating proteins to assess mitochondrial dysfunction (fibroblast growth factor 21 [FGF21] and growth differentiation factor 15 [GDF15]) and kidney injury (lipocalin-2 [LCN2]). Biomarker concentrations are higher in patients with the severe mut0 -type and cblB-type MMA, correlate with a decreased POBT, and show a significant response postliver transplant. Additional circulating and imaging markers to assess disease burden are necessary to monitor disease progression. A combination of biomarkers reflecting disease severity and multisystem involvement will be needed to help stratify patients for clinical trials and assess the efficacy of new therapies for MMA.

Abnormal chondrocyte development in a zebrafish model of cblC syndrome restored by an MMACHC cobalamin binding mutant.

Variants in the MMACHC gene cause combined methylmalonic acidemia and homocystinuria cblC type, the most common inborn error of intracellular cobalamin (vitamin B12) metabolism. cblC is associated with neurodevelopmental, hematological, ocular, and biochemical abnormalities. In a subset of patients, mild craniofacial dysmorphia has also been described. Mouse models of Mmachc deletion are embryonic lethal but cause severe craniofacial phenotypes such as facial clefts. MMACHC encodes an enzyme required for cobalamin processing and variants in this gene result in the accumulation of two metabolites: methylmalonic acid (MMA) and homocysteine (HC). Interestingly, other inborn errors of cobalamin metabolism, such as cblX syndrome, are associated with mild facial phenotypes. However, the presence and severity of MMA and HC accumulation in cblX syndrome is not consistent with the presence or absence of facial phenotypes. Thus, the mechanisms by which mutations in MMACHC cause craniofacial defects are yet to be completely elucidated. Here we have characterized the craniofacial phenotypes in a zebrafish model of cblC (hg13) and performed restoration experiments with either a wildtype or a cobalamin binding deficient MMACHC protein. Homozygous mutants did not display gross morphological defects in facial development but did have abnormal chondrocyte nuclear organization and an increase in the average number of neighboring cell contacts, both phenotypes were fully penetrant. Abnormal chondrocyte nuclear organization was not associated with defects in the localization of neural crest specific markers, sox10 (RFP transgene) or barx1. Both nuclear angles and the number of neighboring cell contacts were fully restored by wildtype MMACHC and a cobalamin binding deficient variant of the MMACHC protein. Collectively, these data suggest that mutation of MMACHC causes mild to moderate craniofacial phenotypes that are independent of cobalamin binding.

Elevated CO2 Priming as a Sustainable Approach to Increasing Rice Tiller Number and Yield Potential.

Tillering and yield are linked in rice, with significant efforts being invested to understand the genetic basis of this phenomenon. However, in addition to genetic factors, tillering is also influenced by the environment. Exploiting experiments in which seedlings were first grown in elevated CO2 (eCO2) before transfer and further growth under ambient CO2 (aCO2) levels, we found that even moderate exposure times to eCO2 were sufficient to induce tillering in seedlings, which was maintained in plants grown to maturity plants in controlled environment chambers. We then explored whether brief exposure to eCO2 (eCO2 priming) could be implemented to regulate tiller number and yield in the field. We designed a cost-effective growth system, using yeast to increase the CO2 level for the first 24 days of growth, and grew these seedlings to maturity in semi-field conditions in Malaysia. The increased growth caused by eCO2 priming translated into larger mature plants with increased tillering, panicle number, and improved grain filling and 1000 grain weight. In order to make the process more appealing to conventional rice farmers, we then developed a system in which fungal mycelium was used to generate the eCO2 via respiration of sugars derived by growing the fungus on lignocellulosic waste. Not only does this provide a sustainable source of CO2, it also has the added financial benefit to farmers of generating economically valuable oyster mushrooms as an end-product of mycelium growth. Our experiments show that the system is capable of generating sufficient CO2 to induce increased tillering in rice seedlings, leading eventually to 18% more tillers and panicles in mature paddy-grown crop. We discuss the potential of eCO2 priming as a rapidly implementable, broadly applicable and sustainable system to increase tillering, and thus yield potential in rice.

Abnormal chondrocyte intercalation in a zebrafish model of cblC syndrome restored by an MMACHC cobalamin binding mutant.

Variants in the MMACHC gene cause combined methylmalonic acidemia and homocystinuria cblC type, the most common inborn error of intracellular cobalamin (vitamin B12) metabolism. cblC is associated with neurodevelopmental, hematological, ocular, and biochemical abnormalities. In a subset of patients, mild craniofacial dysmorphia has also been described. Mouse models of Mmachc deletion are embryonic lethal but cause severe craniofacial phenotypes such as facial clefts. MMACHC encodes an enzyme required for cobalamin processing and variants in this gene result in the accumulation of two metabolites: methylmalonic acid (MMA) and homocysteine (HC). Interestingly, other inborn errors of cobalamin metabolism, such as cblX syndrome, are associated with mild facial phenotypes. However, the presence and severity of MMA and HC accumulation in cblX syndrome is not consistent with the presence or absence of facial phenotypes. Thus, the mechanisms by which mutation of MMACHC cause craniofacial defects have not been completely elucidated. Here we have characterized the craniofacial phenotypes in a zebrafish model of cblC ( hg13 ) and performed restoration experiments with either wildtype or a cobalamin binding deficient MMACHC protein. Homozygous mutants did not display gross morphological defects in facial development, but did have abnormal chondrocyte intercalation, which was fully penetrant. Abnormal chondrocyte intercalation was not associated with defects in the expression/localization of neural crest specific markers, sox10 or barx1 . Most importantly, chondrocyte organization was fully restored by wildtype MMACHC and a cobalamin binding deficient variant of MMACHC protein. Collectively, these data suggest that mutation of MMACHC causes mild to moderate craniofacial phenotypes that are independent of cobalamin binding.

Systemic gene therapy for methylmalonic acidemia using the novel adeno-associated viral vector 44.9.

Methylmalonic acidemia (MMA) is a severe and potentially lethal autosomal recessive inborn error of metabolism most frequently caused by mutations in the methylmalonyl-CoA mutase (MMUT) gene. Proof-of-concept adeno-associated virus (AAV) gene therapy studies using mouse models of MMA have demonstrated promise for this therapeutic approach but translation to the clinic could be limited by preexisting capsid immunity and vector potency. Here we explore the efficacy of a novel clade E capsid, 44.9, as a serotype for systemic AAV gene therapy for MMA. An anti-AAV44.9 neutralizing antibody (NAb) survey in adult volunteers (n = 19) and a large cohort of MMA patients (n = 48) revealed a seroprevalence rate of ∼26% and 13%, respectively. The efficacy of AAV44.9 gene delivery was examined in two murine models of MMA, representing neonatal lethal and juvenile phenotypes of MMA. Systemic delivery of the AAV44.9-Mmut vector prevented lethality and lowered disease-related metabolites in MMA mice. Tissue biodistribution and transgene expression studies in treated MMA mice showed that AAV44.9 was efficient at transducing the liver and heart. In summary, we establish that AAV44.9 exhibits a low prevalence of preexisting NAb in humans, is highly efficacious in the treatment of clinically severe MMA mouse models and is therefore a promising vector for clinical translation.

Induced Genetic Variations in Stomatal Density and Size of Rice Strongly Affects Water Use Efficiency and Responses to Drought Stresses.

Rice (Oryza sativa L.) is an important food crop relied upon by billions of people worldwide. However, with increasing pressure from climate change and rapid population growth, cultivation is very water-intensive. Therefore, it is critical to produce rice that is high-yielding and genetically more water-use efficient. Here, using the stabilized fast-neutron mutagenized population of Jao Hom Nin (JHN) - a popular purple rice cultivar - we microscopically examined hundreds of flag leaves to identify four stomatal model mutants with either high density (HD) or low density (LD) stomata, and small-sized (SS) or large-sized (LS) stomata. With similar genetic background and uniformity, the stomatal model mutants were used to understand the role of stomatal variants on physiological responses to abiotic stress. Our results show that SS and HD respond better to increasing CO2 concentration and HD has higher stomatal conductance (gs) compared to the other stomatal model mutants, although the effects on gas exchange or overall plant performance were small under greenhouse conditions. In addition, the results of our drought experiments suggest that LD and SS can better adapt to restricted water conditions, and LD showed higher water use efficiency (WUE) and biomass/plant than other stomatal model mutants under long-term restricted water treatment. Finally, our study suggests that reducing stomata density and size may play a promising role for further work on developing a climate-ready rice variety to adapt to drought and heat stress. We propose that low stomata density and small size have high potential as genetic donors for improving WUE in climate-ready rice.

Probing the functional consequence and clinical relevance of CD320 p.E88del, a variant in the transcobalamin receptor gene.

The biological and clinical significance of the p.E88del variant in the transcobalamin receptor, CD320, is unknown. This allele is annotated in ClinVar as likely benign, pathogenic, and of uncertain significance. To determine functional consequence and clinical relevance of this allele, we employed cell culture and genetic association studies. Fibroblasts from 16 CD320 p.E88del homozygotes exhibited reduced binding and uptake of cobalamin. Complete ascertainment of newborns with transiently elevated C3 (propionylcarnitine) in New York State demonstrated that homozygosity for CD320 p.E88del was over-represented (7/348, p < 6 × 10-5 ). Using population data, we estimate that ~85% of the p.E88del homozygotes born in the same period did not have elevated C3, suggesting that cobalamin metabolism in the majority of these infants with this genotype is unaffected. Clinical follow-up of 4/9 homozygous individuals uncovered neuropsychological findings, mostly in speech and language development. None of these nine individuals exhibited perturbation of cobalamin metabolism beyond the newborn stage even during periods of acute illness. Newborns homozygous for this allele in the absence of other factors are at low risk of requiring clinical intervention, although more studies are required to clarify the natural history of various CD320 variants across patient populations.

ZBTB11 dysfunction: spectrum of brain abnormalities, biochemical signature and cellular consequences.

Bi-allelic pathogenic variants in ZBTB11 have been associated with intellectual developmental disorder, autosomal recessive 69 (MRT69; OMIM 618383). We report five patients from three families with novel, bi-allelic variants in ZBTB11. We have expanded the clinical phenotype of MRT69, documenting varied severity of atrophy affecting different brain regions and described combined malonic and methylmalonic aciduria as a biochemical manifestation. As ZBTB11 encodes for a transcriptional regulator, we performeded chromatin immunoprecipitation-sequencing targeting ZBTB11 in fibroblasts from patients and controls. Chromatin immunoprecipitation-sequencing revealed binding of wild-type ZBTB11 to promoters in 238 genes, among which genes encoding proteins involved in mitochondrial functions and RNA processing are over-represented. Mutated ZBTB11 showed reduced binding to 61 of the targeted genes, indicating that the variants act as loss of function. Most of these genes are related to mitochondrial functions. Transcriptome analysis of the patient fibroblasts revealed dysregulation of mitochondrial functions. In addition, we uncovered that reduced binding of the mutated ZBTB11 to ACSF3 leads to decreased ACSF3 transcript level, explaining combined malonic and methylmalonic aciduria. Collectively, these results expand the clinical spectrum of ZBTB11-related neurological disease and give insight into the pathophysiology in which the dysfunctional ZBTB11 affect mitochondrial functions and RNA processing contributing to the neurological and biochemical phenotypes.

Severity modeling of propionic acidemia using clinical and laboratory biomarkers.

PURPOSE: To conduct a proof-of-principle study to identify subtypes of propionic acidemia (PA) and associated biomarkers. METHODS: Data from a clinically diverse PA patient population ( https://clinicaltrials.gov/ct2/show/NCT02890342 ) were used to train and test machine learning models, identify PA-relevant biomarkers, and perform validation analysis using data from liver-transplanted participants. k-Means clustering was used to test for the existence of PA subtypes. Expert knowledge was used to define PA subtypes (mild and severe). Given expert classification, supervised machine learning (support vector machine with a polynomial kernel, svmPoly) performed dimensional reduction to define relevant features of each PA subtype. RESULTS: Forty participants enrolled in the study; five underwent liver transplant. Analysis with k-means clustering indicated that several PA subtypes may exist on the biochemical continuum. The conventional PA biomarkers, plasma total 2-methylctirate and propionylcarnitine, were not statistically significantly different between nontransplanted and transplanted participants motivating us to search for other biomarkers. Unbiased dimensional reduction using svmPoly revealed that plasma transthyretin, alanine:serine ratio, GDF15, FGF21, and in vivo 1-13C-propionate oxidation, play roles in defining PA subtypes. CONCLUSION: Support vector machine prioritized biomarkers that helped classify propionic acidemia patients according to severity subtypes, with important ramifications for future clinical trials and management of PA.

1-13C-propionate breath testing as a surrogate endpoint to assess efficacy of liver-directed therapies in methylmalonic acidemia (MMA).

PURPOSE: To develop a safe and noninvasive in vivo assay of hepatic propionate oxidative capacity. METHODS: A modified 1-13C-propionate breath test was administered to 57 methylmalonic acidemia (MMA) subjects, including 19 transplant recipients, and 16 healthy volunteers. Isotopomer enrichment (13CO2/12CO2) was measured in exhaled breath after an enteral bolus of sodium-1-13C-propionate, and normalized for CO2 production. 1-13C-propionate oxidation was then correlated with clinical, laboratory, and imaging parameters collected via a dedicated natural history protocol. RESULTS: Lower propionate oxidation was observed in patients with the severe mut0 and cblB subtypes of MMA, but was near normal in those with the cblA and mut- forms of the disorder. Liver transplant recipients demonstrated complete restoration of 1-13C-propionate oxidation to control levels. 1-13C-propionate oxidation correlated with cognitive test result, growth indices, bone mineral density, renal function, and serum biomarkers. Test repeatability was robust in controls and in MMA subjects (mean coefficient of variation 6.9% and 12.8%, respectively), despite widely variable serum methylmalonic acid concentrations in the patients. CONCLUSION: Propionate oxidative capacity, as measured with 1-13C-propionate breath testing, predicts disease severity and clinical outcomes, and could be used to assess the therapeutic effects of liver-targeted genomic therapies for MMA and related disorders of propionate metabolism. TRIAL REGISTRATION: This clinical study is registered in www.clinicaltrials.gov with the ID: NCT00078078. Study URL: http://clinicaltrials.gov/ct2/show/NCT00078078.

Considerations of expanded carrier screening: Lessons learned from combined malonic and methylmalonic aciduria.

BACKGROUND: Expanded carrier screening (ECS) utilizes high-throughput next-generation sequencing to evaluate an individual's carrier status for multiple conditions. Combined malonic and methylmalonic aciduria (CMAMMA) due to ACSF3 deficiency is a rare inherited disease included in such screening panels. Some cases have been reported with metabolic symptoms in childhood yet other cases describe a benign clinical course, suggesting the clinical phenotype is not well defined. METHODS/CASE REPORT: Clinical and laboratory findings during the prenatal period were obtained retrospectively from medical records. RESULTS: A 37-year-old nulliparous woman and her partner were each identified as carriers of ACSF3 variants and presented at 9 weeks gestation for prenatal genetic consultation. The couple received extensive genetic counseling and proceeded with chorionic villus sampling at 11 weeks gestation. Subsequent analysis confirmed that the fetus inherited both parental ACSF variants. The couple was devastated by the results and after reviewing options of pregnancy continuation and termination, they decided to terminate the pregnancy. Following this decision, the patient was diagnosed with acute stress disorder. CONCLUSION: This case highlights how expanded carrier screening adds complexity to reproductive decision-making. Stronger guidelines and additional research are needed to direct and evaluate the timing, composition, and implementation of ECS panels.

Improvements in Neighborhood Socioeconomic Conditions May Improve Resident Diet.

Neighborhood socioeconomic conditions (NSECs) are associated with resident diet, but most research has been cross-sectional. We capitalized on a natural experiment in Pittsburgh, Pennsylvania, in which 1 neighborhood experienced substantial investments and a sociodemographically similar neighborhood that did not, to examine pathways from neighborhood investments to changed NSECs and changed dietary behavior. We examined differences between renters and homeowners. Data were from a random sample of households (n = 831) in each of these low-income Pittsburgh neighborhoods that were surveyed in 2011 and 2014. Structural equation modeling tested direct and indirect pathways from neighborhood to resident dietary quality, adjusting for individual-level sociodemographics, with multigroup testing by homeowners versus renters. Neighborhood investments were directly associated with improved dietary quality for renters (ß = 0.27, 95% confidence interval (CI): 0.05, 0.50) and homeowners (ß = 0.51, 95% CI: 0.10, 0.92). Among renters, investments also were associated with dietary quality through a positive association with commercial prices (ß = 0.34, 95% CI: 0.15, 0.54) and a negative association with residential prices (ß = -0.30, 95% CI: -0.59, -0.004). Among homeowners, we did not observe any indirect pathways from investments to dietary quality through tested mediators. Investing in neighborhoods may support resident diet through improvements in neighborhood commercial environments for renters, but mechanisms appear to differ for homeowners.

An audit tool for longitudinal assessment of the health-related characteristics of urban neighborhoods: implementation methods and reliability results.

BACKGROUND: Improving the neighborhood environment may help address chronic disease and mortality. To identify neighborhood features that are predictors of health, objective assessments of the environment are used. Multiple studies have reported on cross-sectional assessments of health-related neighborhood features using direct observation. As study designs expand to better understand causation and predictors of change, there is a need to test whether direct observation methods are adequate for longitudinal assessment. To our knowledge, this is the first study to report on the reliability of repeated measurements of the neighborhood environment, and their stability, over time. METHODS: The Pittsburgh Hill/Homewood Research on Neighborhood Change and Health (PHRESH) study conducted longitudinal assessments in two low-income, African American neighborhoods at three waves (years 2012, 2015, 2017). The PHRESH audit tool is a modification of earlier validated tools, with an emphasis on environment features relevant for physical activity, sleep, and obesogenic behaviors. Trained data-collector pairs conducted direct observations of a 25% sample of street segments in each neighborhood. At each wave, we audited a sub-sample of street segments twice and assessed reliability using percentage inter-observer agreement and krippendorf's alpha statistics. Stability of these items was assessed as exhibiting moderate or high agreement at every time point. RESULTS: Across waves, a majority (81%) of the items consistently demonstrated moderate to high agreement except for items such as public/communal space, amount of shade, sidewalk features, number of traffic lanes, garden/flower bed/planter, art/statue/monument, amount of trash, and physical disorder. The list of items with poor agreement includes features that are easy to miss (e.g. flower bed/planter), hard to assess from outside (e.g. public/communal space), or may change quickly (e.g. amount of trash). CONCLUSION: In this paper, we have described implementation methods, reliability results and lessons learned to inform future studies of change. We found the use of consistent methods allowed us to conduct reliable, replicable longitudinal assessments of the environment. Items that did not exhibit stability are less useful for detecting real change over time. Overall, the PHRESH direct observation tool is an effective and practical instrument to detect change in the neighborhood environment.

Factors related to health civic engagement: results from the 2018 National Survey of Health Attitudes to understand progress towards a Culture of Health.

BACKGROUND: Civic engagement, including voting, volunteering, and participating in civic organizations, is associated with better psychological, physical and behavioral health and well-being. In addition, civic engagement is increasingly viewed (e.g., in Robert Wood Johnson Foundation's Culture of Health action framework) as a potentially important driver for raising awareness of and addressing unhealthy conditions in communities. As such, it is important to understand the factors that may promote civic engagement, with a particular focus on the less-understood, health civic engagement, or civic engagement in health-related and health-specific activities. Using data from a nationally representative sample of adults in the United States (U.S.), we examined whether the extent to which individuals feel they belong in their community (i.e., perceived sense of community) and the value they placed on investing in community health were associated with individuals' health civic engagement. METHODS: Using data collected on 7187 nationally representative respondents from the 2018 National Survey of Health Attitudes, we examined associations between sense of community, valued investment in community health, and perceived barriers to taking action to invest in community health, with health civic engagement. We constructed continuous scales for each of these constructs and employed multiple linear regressions adjusting for multiple covariates including U.S. region and city size of residence, educational attainment, family income, race/ethnicity, household size, employment status, and years living in the community. RESULTS: Participants who endorsed (i.e., responded with mostly or completely) all 16 sense of community scale items endorsed an average of 22.8% (95%CI: 19.8-25.7%) more of the health civic engagement scale items compared with respondents who did not endorse any of the sense of community items. Those who endorsed (responded that it was an important or top priority) all items capturing valued investment in community health endorsed 14.0% (95%CI: 11.2-16.8%) more of the health civic engagement items than those who did not endorse any valued investment in community health items. CONCLUSIONS: Health civic engagement, including voting and volunteering to ultimately guide government decisions about health issues, may help improve conditions that influence health and well-being for all. Focusing on individuals' sense of community and highlighting investments in community health may concurrently be associated with increased health civic engagement and improved community and population health.