Network analysis of eating disorder symptoms in women in perimenopause and early postmenopause

OBJECTIVE

Eating disorders (EDs) are often stereotyped as disorders of adolescence and young adulthood; however, they can occur at any age. Prevalence of EDs at midlife are approximately 3.5% and specific symptoms at midlife can have prevalences as high as 29.3%. Studies also inconsistently suggest that EDs and related symptoms may be more prevalent in midlife aged women during perimenopause compared with midlife aged women at pre-menopause. To date few studies have examined the structure of and associations between ED symptoms in women specifically during perimenopause and early postmenopause. Thus, the purpose of the current study is to investigate the structure of ED symptoms specifically during perimenopause and early postmenopause.

METHODS

Participants included 36 participants (45-61 y old) in a larger clinical trial who completed the Eating Disorder Examination Questionnaire (EDE-Q) at a baseline study visit. Network analysis statistical models were used to examine the structure of and associations between ED symptoms assessed via the EDE-Q.

RESULTS

Shape dissatisfaction and weight dissatisfaction were the top 2 central symptoms in the network.

CONCLUSIONS

Results corroborate previous studies and indicate that, similar to young adult samples, dissatisfaction with body image is a core feature of ED pathology across the lifespan.

Understanding comorbidity between eating disorder and premenstrual symptoms using a network analysis approach

Eating disorder symptoms are associated with ovarian hormones and fluctuate predictably across the menstrual cycle. However, the specific symptoms that underlie these associations remain unclear. The current study aims to examine which specific eating disorder and premenstrual symptoms confer risk and maintain comorbidity using network analysis. Eating disorder and premenstrual symptoms were measured using the Eating Pathology Symptoms Inventory and the Daily Record of Severity of Problems, respectively, in a large sample of young adult females. Network analysis was used to explicate the structure of eating and premenstrual symptom networks separately and together. Eating disorder networks replicated previous literature and identified body dissatisfaction as a core feature, but was unique in identifying monitoring calories as an additional core feature. Central symptoms identified in the premenstrual symptom network were symptoms interference with daily life and activities and negative emotions brought on by hormone changes. Bridge symptoms between networks were identified as relating to eating behaviors, interference with daily activities, joint and muscle pain, and negative emotions brought on by hormone changes. This study suggests that the links between eating disorder and premenstrual symptoms extend past their individual effects on eating behavior and are indicative of a shared underlying mechanism.

Recommendations to encourage participation of individuals from diverse backgrounds in psychiatric genetic studies

We present innovative research practices in psychiatric genetic studies to ensure representation of individuals from diverse ancestry, sex assigned at birth, gender identity, age, body shape and size, and socioeconomic backgrounds. Due to histories of inappropriate and harmful practices against marginalized groups in both psychiatry and genetics, people of certain identities may be hesitant to participate in research studies. Yet their participation is essential to ensure diverse representation, as it is incorrect to assume that the same genetic and environmental factors influence the risk for various psychiatric disorders across all demographic groups. We present approaches developed as part of the Eating Disorders Genetics Initiative (EDGI), a study that required tailored approaches to recruit diverse populations across many countries. Considerations include research priorities and design, recruitment and study branding, transparency, and community investment and ownership. Ensuring representation in participants is costly and funders need to provide adequate support to achieve diversity in recruitment in prime awards, not just as supplemental afterthoughts. The need for diverse samples in genetic studies is critical to minimize the risk of perpetuating health disparities in psychiatry and other health research. Although the EDGI strategies were designed specifically to attract and enroll individuals with eating disorders, our approach is broadly applicable across psychiatry and other fields.

Structural brain correlates of eating pathology symptom dimensions: A systematic review

There has been an increasing interest in neurobiological correlates of psychopathology with a growing consensus that such research questions are best investigated through dimensional approaches to psychopathology. One area that has been noticeably understudied in this regard is eating pathology. Therefore, the goal of the current systematic review was to summarize research on structural brain correlates of symptom dimensions of eating-related pathology. Google Scholar and PubMed databases were searched following the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. Results suggest that restrained eating is associated with increased GMV (gray matter volume) in regions involved in emotional, visuo-spatial, attentional, and self-related processing. Disinhibitory eating is associated with increased GMV in regions involved in reward value of food-related stimuli and decreased GMV in regions involved in emotional/motivational processing. All told, results suggest that dimensions of eating pathology have differential neuroanatomical correlates potentially suggesting differences in neural pathways which has the potential to support future biologically-driven classification and treatment efforts.

Maternal care mediates the effects of nutrition and responsive stimulation interventions on young children's growth

BACKGROUND

Undernutrition contributes to at least half the estimated six million annual childhood deaths worldwide. Furthermore, one in three children fails to meet their developmental potential because of risks including stunting, illness, under-stimulation, poor responsive interactions and maternal depressive symptoms. Our study investigates the role of caregiving processes on children's height-for-age at 2 and 4 years.

METHODS

The Pakistan Early Child Development Scale-up study assessed the longitudinal effectiveness of early nutrition and responsive stimulation interventions on growth and development at 4 years of age. In total, 1302 children were followed up from birth to 4 years. We leveraged path analyses to explore potential mediators of early intervention effects on children's height-for-age at 4 years, including maternal depressive symptoms, mother-child interaction quality, diarrhoeal illness and height-for-age at 2 years.

RESULTS

Our final model had excellent model fit (comparative fix index = 0.999, Tucker-Lewis index = 0.998, root mean square error of approximation = 0.008) and showed that mother-child interaction quality mediated the effects of both enhanced nutrition and responsive stimulation interventions on height-for-age at 4 years via its longitudinal stability from 2 years of age (β = 0.016, p = 0.005; β = 0.048, p < 0.001, respectively). Further, diarrhoeal illness mediated the effects of maternal depressive symptoms at 1 year post partum on children's height-for-age at 4 years via the longitudinal stability of height-for-age z-score from 2 years of age onwards (β = -0.007, p = 0.019).

CONCLUSIONS

The quality of early caregiving experience mediated the association between both interventions and height-for-age. The effect of maternal depressive symptoms on growth was mediated by diarrhoeal illness. Programmatic approaches to child nutrition and growth must address all these potentially modifiable factors.

An assessment of gastric emptying by breathalyser

1 A breathalyser has been used to measure blood alcohol levels at short intervals to produce an absorption curve which we have shown is reproducible. 2 Changes in the rate of absorption which reflect changes in gastric emptying times produced by metoclopromide and propantheline have been demonstrated. 3 The breathalyser technique described appears to offer a simple method of studying the effects of drugs on the rate of gastric emptying.

The covalent structure of cartilage collagen. Amino acid sequence of residues 552-661 of bovine alpha1(II) chains

The covalent structure of the first 111 residues from the N-terminus of peptide alpha1(II)-CB10 from bovine nasal-cartilage collagen is presented. This region comprises residues 552-661 of the alpha1(II) chain. The sequence was determined by automated Edman degradation of peptide alpha1(II)-CB10 and of peptides produced by cleavage with trypsin and hydroxylamine. Comparison of this region of the alpha1(II) chain with the homologous segment of the alpha1(I) chain indicated a homology level of 85%, slightly higher than that of 81% reported for the N-terminal region of the alpha1(II) chain (Butler, Miller & Finch (1976) Biochemistry15, 3000-3006). The occurrence of two residues of glycosylated hydroxylysine was established at positions 564 and 603, the first present exclusively as galactosylhydroxylysine and the latter as a mixture of galactosylhydroxylysine and glucosylgalactosylhydroxylysine. Also, two residues at positions 648 and 657 were tentatively identified as glycosylated hydroxylysines. The amino acid sequences adjacent to the hydroxylysine residues so far identified in the alpha1(II) chain were compared with the homologous regions of the alpha1(I) and alpha2 chains, but no obvious prerequisite for hydroxylation could be seen. From comparison with the homologous sequence of the alpha1(I) chain, it appears that the alpha1(II)-chain sequence presented here contains three more amino acids than that reported for the alpha1(I) chain. This triplet would be interposed between residues 63 and 64 of the reported sequence of peptide alpha1(I)-CB7 from calf skin collagen. Data on the purification of the subpeptides and their amino acid compositions have been deposited as Supplementary Publication SUP 50087 (7 pages) at the British Library Lending Division, Boston Spa, Wetherby, West Yorkshire LS23 7BQ, U.K., from whom copies can be obtained on the terms indicated in Biochem. J. (1978) 169, 5.

Effect of growth environment on Pseudomonas aeruginosa killing by rabbit polymorphonuclear leudocytes and cationic proteins

Pseudomonas aeruginosa grown in a chemostat under carbon- and magnesium-limited conditions showed varying resistance to killing by rabbit peritoneal exudate polymorphonuclear leukocytes. Slow-growing (D = 0.05 h-1), magnesium-limited cells were significantly more resistant to the lethal effects of the phagocytes than were fast-growing magnesium-limited cells and carbon-limited cells (D = 0.05 h-1 and D = 0.5 h-1, respectively). The resistance of magnesium-limited cells to killing by cationic proteins isolated from the leukocytes was shown to be growth-rate dependent, the slowest-growing (D = 0.05 h-1) cells being the most resistant. Carbon-limited cells were sensitive to killing by the cationic proteins at all growth rates tested. Antisera raised in rabbits to all types of cells and commercial anti-Pseudomonas serum rapidly agglutinated magnesium-limited cells but failed to agglutinate carbon-limited cells. There was some indication that slow-growing (D = 0.05 h-1), magnesium-limited cells agglutinated most readily with both types of antisera. No difference was detected in the mouse toxicity of heat-killed cells grown under the various conditions.

The covalent structure of cartilage collagen. Evidence for sequence heterogeneity of bovine alpha1(II) chains

During studies on the amino acid sequence of bovine nasal cartilage collagen, the cyanogen bromide peptide alpha1(II)-CB11 was degraded to smaller peptides with trypsin. One of the tryptic peptides, T5, which contained 39 residues was shown by amino acid and sequence analyses to occur in a predominant form that contained glutamine at position 5 and in a second form with leucine at this site. In addition to the heterogeneity at this position, amino acid analyses of five different preparations revealed that the peptide with leucine contained a seryl residue not found in the major form. Sequence heterogeneity at a third position of alpha1(II) was demonstrated by the isolation of a hexapeptide (T2) from the trypsin digest of alpha1(II)-CB11 which contained 0.21 residue of alanine and 0.77 of leucine. Both the leucine and alanine of T2 were removed after the second cycle of subtractive Edman degradation. These data show that at least two types of alpha1(II) chains, designated as alpha1(II)Major and alpha1(II)Minor, exist in bovine nasal cartilage. Further considerations suggest that these two chains are probably not variants derived from allelic genes but are the products of separate genes.

The covalent structure of cartilage collagen. Amino acid sequence of the NH2-terminal helical portion of the alpha 1 (II) chain

The amino acid sequence of 162 residues from the NH2-terminal region of bovine alpha 1 (II) is reported. Automated sequence analysis of chains from pepsin-treated type II collagen indicated the sequence and order of two CNBr peptides, alpha 1 (II)-CB2 and alpha 1 (II)-CB3, at the beginning of the repetitive triplet sequence of alpha 1 (II). The sequences of alpha 1 (II)-CB6, alpha 1 (II),-CB12, and 39 residues of alpha 1 (II)-CB11 were determined largely by automated Edman degradation. Comparative sequence data are reported which indicate that the level of homology between alpha 1 (I) and alpha 1 (II) chains in the NH2-terminal region is about 80%. A similar level of homology was reported for the central portions of these chains (Butler, W.T., Miller, E.J., Finch, J.E., Jr., and Inagami, T. (1974), Biochem. Biophys. Res. Commun. 57 190). The degree of intraspecies variability between chain types is thus greater than the interspecies variability for a single chain type. Within the sequence reported here, the alpha 1 (II) chain contains glucosylgalactosylhydroxylysine at three positions. The corresponding sequence of alpha 1 (I) contains only one clycosylated hydroxylysine with the other two positions occupied by lysyl residues.

Cleavage of Type II and III collagens with mammalian collagenase: site of cleavage and primary structure at the NH2-terminal portion of the smaller fragment released from both collagens

Collagenase cleavage of human Type II and III collagens has been studied using a highly purified preparation of rabbit tumor collagenase. Progress of the reactions in solution was followed by viscometry and the results indicated that under the conditions employed Type III collagen molecules were cleaved at approximately five times the rate of Type II molecules. Cleavage products of the reactions were isolated in denatured form by agarose molecular sieve chromatography. The molecular weights and amino acid compositions of the products demonstrated that Type II and III molecules had been cleaved at the characteristic three-quarter, one-quarter locus, giving rise to a large fragment derived from the NH2-terminal portion of the molecule and a smaller fragment representing the COOH-terminal region. The amino acid sequence at the NH2-terminal portion of the smaller fragment derived from Type II collagen was determined to be Ile-Ala-Gly-Gln-Arg, and the corresponding region from Type III collagen was found to have the sequence Leu-Ala Gly-Leu-Arg. These sequences for alpha1(II) and alpha1(III) chains adjacent to the site of collagenase cleavage along with previous data for alpha1(I) and alpha2 chains indicate that the minimum specific sequence required for collagenase cleavage is Gly-Ile-Ala or Gly-Leu-Ala. Inspection of the available sequence data for collagen alpha chains indicates that the latter sequences are found in at least three additional locations at which collagenase cleavage does not occur. Each of the sequences which are apparently not substrates for collagenase, however, are followed by a Gly-X-Hyp sequence. We suggest, then, that a minimum of five residues in collagen alpha chains COOH-terminal to the cleavage site comprise the substrate recognition site.