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PubMed2026

Can Psychiatric Genetics Advance Without Incorporating a Life Course Perspective?

Psychiatric disorders unfold over the life course; however, genomic studies of these conditions overwhelmingly rely on phenotypes collected at a single time point, often in adulthood. Therefore, genome-wide association studies (GWASs) of psychiatric conditions may miss genetic variants with time-varying relevance to etiology, prevention, and treatment, such as those that influence trajectories of symptoms and behaviors, age at onset, course of treatment response, and the co-evolution of comorbidities. With recent advances in longitudinal biobanks and analytic tools, we posit that incorporating a life course perspective in psychiatric genetics will enable critically relevant insights into each of these areas of investigation. We propose that the current inconsistent portability of polygenic scores across age groups can be reconciled through the design of carefully considered longitudinal GWASs in age-diverse samples. Pioneering longitudinal GWASs in psychiatry have revealed novel genomic signals associated with time-dependent phenotypes that are distinct from those influencing lifetime diagnosis, suggesting that the study of longitudinal phenotypes will complement cross-sectional approaches and empower biological and therapeutic discoveries. Advances in post-GWAS functional annotation resources and analytic approaches now enable us to contextualize the genetic contributions to psychiatric disorders as dynamic age- and exposure-dependent processes. Although longitudinal GWASs pose unique challenges with regard to data availability, selection bias, and missing data, integrating temporality into psychiatric genetics at scale is now attainable and promises to reveal novel biology and therapeutic opportunities for psychiatric conditions.

Cohort study↗

PubMed2026

Fracture-related infection following open forefoot fractures caused by dropped objects.

INTRODUCTION: This study evaluated the rate of fracture-related infection (FRI) of open forefoot fractures caused by dropped objects, and examined associations of treatment characteristics, including intravenous and oral antibiotics and operative debridement, with FRI. METHODS: Patients aged 18-80 years who sustained an open metatarsal or phalanx fracture caused by a dropped object between January 2021 and June 2024 were retrospectively identified from two Level 1 trauma centers. The primary outcome was FRI, determined based on the FRI consensus criteria. FRI rates were compared between those who underwent irrigation and debridement (I&D) at bedside versus in the operating room, and between those who received oral versus intravenous (IV) antibiotics. Patient characteristics were also analyzed to determine host factors associated with FRI. RESULTS: A total of 86 patients (median age 41 years [IQR: 29-56], 58% male) were included. Eighty-five patients (99%) received antibiotics, 31 (36%) of whom received intravenous antibiotics. Sixty-six patients (77%) received an I&D at presentation, 57 (66%) at bedside and 9 (10%) in the operating room. Thirteen patients (15%, 95% CI: 8.3%-24%) developed FRI. No significant difference in FRI rate was found between patients who underwent I&D at bedside versus in the operating room (12% versus 11%, p > 0.99). Among patients who did not undergo I&D in the operating room, no significant difference in FRI rate was found between patients who received oral versus IV antibiotics (17% versus 13%, p = 0.74). Insulin-dependent diabetes was associated with an increased risk of FRI (60% versus 12%, p = 0.02). CONCLUSIONS: In this cohort, one in seven patients developed FRI. No statistically significant differences in FRI rates were observed by I&D setting (bedside versus operative) or antibiotic route (oral versus IV), including in a subgroup analysis excluding patients treated with operating room I&D. These findings are limited by sample size and potential treatment selection bias and should not be interpreted as evidence of equivalence. Management should be individualized based on clinical judgement, resource availability, and patient factors. These findings can help guide the management protocols for "dropped objects" open forefoot fractures presenting to urgent care and the emergency department. LEVEL OF EVIDENCE: Therapeutic Level III.

Humans↗

PubMed2026

Quality of life and gender identity in females with congenital adrenal hyperplasia after genital restoration surgery: A single-center experience.

BACKGROUND: Legislation restricting surgical interventions in children with differences of sex development (DSD) has intensified debate about female genital restoration surgery (FGRS) in patients with congenital adrenal hyperplasia (CAH). Long-term patient-reported outcomes are needed regarding the optimal timing of surgery. OBJECTIVE: We aimed to assess health-related quality of life (HRQoL), gender identity, and family satisfaction regarding surgical timing and outcome in females with CAH following genital restoration surgery. STUDY DESIGN: Cross-sectional survey of CAH patients who underwent surgery between January 2007 to December 2016 at our institution. Validated instruments (KINDL questionnaire for HRQoL, Utrecht Gender Dysphoria Scale, UGDS) and structured telephone interviews were employed. RESULTS: Data on HRQoL was available for 25 patients (self- and/or parent-reported) out of 56 eligible patients (45% response rate). Median age at first surgery was 6 months (range: 3-137 months). Patients' age at time of participation ranged from 2 to 28 years. All had 21-hydroxylase deficiency (92% salt-wasting form) with Prader grades ranging from II-V. Wound dehiscence requiring secondary suturing occurred in 15% of patients with primary surgery at our center, while only one (4%) patient developed vaginal stenosis after early primary vaginoplasty. Two additional patients (8%) with prior outside surgery required vaginal revision after FGRS at age 12. HRQoL scores were comparable to healthy reference populations across most age groups. Children aged 3-6 and adolescents and young adults showed no significant difference from reference values, while children aged 7-13 showed a slight elevation. None of five patients ≥14 years demonstrated gender dysphoria (all UGDS scores <40, threshold ≥40). 14 patients and families were also interviewed by telephone. All preferred early surgical timing. No family expressed regret about the decision or preferred delayed surgery. DISCUSSION: This study provides validated intermediate-term patient- and parent-reported outcomes after FGRS in CAH. Key limitations include the small sample size, single-center design, and young age of most patients. Selection bias may exist, though participating families included those who underwent revision surgery. The absence of a non-operated comparison group reflects current clinical reality, as nearly all CAH patients with urogenital sinus underwent surgical correction. CONCLUSIONS: Females with CAH reported normal HRQoL and a comfortable female gender identity after early FGRS. The patients and their families expressed a preference for early surgery. However, there is need for longer-term follow-up to assess sexual function and reproductive outcomes as well comparison of outcomes with a non-operated group.

Humans↗

PubMed2026

Stress and risk of breast cancer; findings from a large population-based incident case-control study.

The relationship between stress and breast cancer (BC) remains a topic of debate. We investigated the association between stress experienced within the past year and the risk of BC. Population-based incident case-control study of 600 newly diagnosed BC cases and 600 population controls (18-75 years) recruited in Isfahan, Iran between 2021 and 2023. Logistic regression model with short-term stress as main exposure was used to estimate odds ratios (ORs) and 95% confidence intervals (CI) after adjusting for confounders. Multiplicative interaction was tested between stress and menopausal status as well as other confounders. One-year stress level was significantly associated with BC risk. Compared with women reporting low stress levels, the odds of BC were higher among those with high stress levels in both the unadjusted model (OR = 3.10, 95%Cl: 2.45-3.92) and the fully adjusted model (OR = 3.38; 95%CI (2.56, 4.47)). Based on the statistical test for multiplicative interaction, the association appeared stronger among premenopausal women (adjusted OR = 4.88, 95% CI: 3.17-7.52) than among postmenopausal women (adjusted OR = 2.34, 95% CI: 1.53-3.58), with evidence of interaction by menopausal status (p for interaction = 0.018). Despite the inherent limitations of case-control studies, including potential recall and selection biases, the findings of the current study suggest that higher levels of stress experienced within the past year may be associated with an increased risk of breast cancer, particularly among premenopausal women. Further prospective studies are warranted to clarify the nature and direction of this association.

Humans↗

PubMed1979

Verifying the validity of outcome.

The first article in this series, published in May (page 241), dealt with selection bias and described how to tell if it had crept into a clinical study. This article focuses on the next step in critically evaluating a study: How to assess validity of outcome. Examples illustrate the consequences of failure to fulfill each of the four criteria of valid measurement of outcome.

Female↗

PubMed1977

Children of imprisoned fathers.

John Bowlby's influential 1951 World Health Organization monograph, Maternal Care and Mental Health, pointed to a causal relationship between loss of maternal care and disturbed personality development, and had a profound effect on psychiatrists' thinking about antisocial behavior in particular, and character formation in general. More recently, psychiatric investigators have been increasingly interested in the effects of a child separation from his father. This has been stimulated by sociological concerns for one-parent, fatherless families (Adams, 1973) and by our realizing how historically neglected has been the paternal role in theories of child development. Herzog and Sudia (1971) have recently compiled an extensive bibliography of the fatherless family. Numerous clinical studies of loss of the father, through death (Nagera, 1970; Wolfenstein, 1966; Bonnard, 1964), suicide (Cain and Fast 1966), divorce (McDermott, 1970), military service (Crumley and Blumenthal, 1973), occupations (Rosenfeld et al., 1973), desertion (Thomes, 1968), and mental hospitalization (Schiff, 1965), have all reported various adverse effects, particularly on male children. It has been difficult, however, to sort out the effects of the loss itself from more general prevailing and prior family relationships. My interest in this subject was quickened when I began to see boys brought to a neighborhood clinic for aggressive and antisocial behavior soon after their fathers were imprisoned. I was impressed by the lack of reports in the literature on this form of father separation. I am presenting here my clinical observations of six families seen over a three-year period as part of a general child psychiatric experience at a comprehensive neighborhood health center sponsored by the Massachusetts General Hospital in Boston. Although there are obvious selection biases that limit generalization when families referred to psychiatrists are the only source of information, it seems a useful place to begin an examination of the consequences for children of father-separation as a result of imprisonment.

Adolescent↗

PubMed2026

A reanalysis of the Hitachi cohort study evaluating the effectiveness of low-dose CT screening for lung cancer.

The effectiveness of low-dose thoracic computed tomography (CT) screening for lung cancer for non-smokers or light smokers has been unclear. The results of the Hitachi cohort study performed by the conventional multivariable analysis suggested the reduction of lung cancer mortality by thoracic CT screening, but also revealed the lower all-cause mortality in the CT group, which indicated the existence of self-selection bias. Because the background of the subjects in the CT screening group and that in the X-ray screening group were very different, it is critical to adjust appropriately the confounding factors. In this brief report, we describe a re-evaluation of the results of the Hitachi Cohort Study performed by using more flexible methods, propensity score matching and inverse probability weighting.

epidemiology/public health↗

PubMed2026

GRN rs5848 variant associates with TDP-43 pathology and cancer in opposite directions.

Epidemiologic studies have reported that cancer survivors have a relatively low risk of developing dementia, but the mechanisms underlying that inverse relationship are mostly unknown. The Granulin (GRN) gene single nucleotide variant rs5848 T allele is associated with increased risk of limbic-predominant age-related TDP-43 encephalopathy neuropathologic change (LATE-NC) and hippocampal sclerosis of aging (HS-Aging). The T allele is also associated with lower expression of the cognate protein progranulin (PGRN), which is a mitogen implicated in neoplasia. We examined whether the rs5848 variant associated with LATE-NC/HS-Aging pathology and cancer in the same cohort. This study leveraged genotype data from the Alzheimer's Disease Genomics Consortium (n = 8121) and the Alzheimer's Disease Sequencing Project (n = 3231), with cancer history and neuropathology data drawn from the National Alzheimer's Coordinating Center. The rs5848 T allele was associated with higher odds of LATE-NC (p < 0.001) and was also associated with lower odds of cancer (p = 0.012). Established TMEM106B, APOE, and BIN1 risk alleles for Alzheimer's disease showed no associations with cancer, implying that the GRN-related associations could not be completely explained by selection bias in the study sample. The finding of a specific allele with opposite correlative impact on cancer risk and dementia-related pathology has potential therapeutic implications.

Humans↗

PubMed1979

The preferential codon usages in variable and constant regions of immunoglobulin genes are quite distinct from each other.

The pattern of codon utilization in the variable and constant regions of immunoglobulin genes are compared. It is shown that, in these regions, codon utilizations are quite distinct from one another: For most degenerate codons, there is a selective bias that prefers C and/or G ending codons to U and/or A ending codons in the constant region compared with the bias in the variable region. This would strongly suggest that, in immunoglobulin genes, the bias in code word usage is determined by other factors than those concerning with the translational mechanism such as tRNA availability and codon-anticodon interaction. A possibility is also suggested that this differance of code word usage between them is due to the existence of secondary structure in the constant region but not in the variable region.

Anticodon↗

PubMed1977

Blood pressure in Seventh-day Adventist vegetarians.

The blood pressures (BP) in 418 vegetarian Seventh-day Adventist (SDA) volunteers in Western Australia were compared with those in 290 non-vegetarian volunteers in Narrogin, a Western Australian country town. The mean systolic and diastolic BPs in the SDAs, adjusted for age, sex, height and weight (128.7/76.2 mm of mercury) were significantly less than those in the Narrogin residents (139.3/84.5). It appeared unlikely that these differences could be explained by differences in alcohol, tobacco, tea, coffee or egg consumption, socioeconomic status or physical activity. There was, however, a gradient toward increasing BP with increasing egg intake in SDAs, and SDAs who drank tea or coffee had a higher mean diastolic BP than those who did not (mean difference of 4.2 mm of mercury). The possibility that selective bias or unmeasured environmental differences might explain the difference in BP between the two groups is discussed.

Adult↗

PubMed1979

Implications of alternative sampling strategies for emergency medical service evaluation.

Evaluations of emergency medical service (EMS) programs have been ambiguous, due in part, to problems of sample definition. Four different sampling strategies were studied: 1) all patients in cardiac arrest; 2) patients with a final diagnosis of myocardial infarction (MI); 3) patients with an emergency room diagnosis of "rule out MI"; and 4) patients identified by the ambulance team as a possible MI. Using a regional data base of all ambulance runs, we created study samples based on each of these strategies and measured the error that may be introduced as a result of sample selection. Bias was measured along three parameters of EMS system performance: 1) observed incidence of MI in the ambulance system; 2) condition recognition--the ability of the ambulance team to correctly identify acute cardiac patients; and 3) emergency room and hospital mortality rates. The emergency room diagnosis strategy systematically excludes all false-positives, while samples based on the ambulance team's assessment omit all false-negatives. The final diagnosis strategy yields significant underestimates of cardiac mortality. Samples restricted to cardiac arrests result in biased estimates of both the incidence of MI and the number of deaths.

Ambulances↗

PubMed1978

Adverse reactions to practolol: some observations on the possible relevence to immune mechanisms.

HLA antigen frequencies were determined in patients who had suffered adverse reaction to the beta-adrenergic blocking agent, practolol. No statistically significant differences were observed between these patients and control groups. The latter were selected to include two separate groups, normal random healthy population controls, and controls who had taken practolol with no apparent adverse effects. Patients suffering from the very severe form of reaction, sclerosing peritonitis, were analysed separately from those with other lesion e.g. ocular symptoms, but did not show any significant differences. Altered HLA antigen frequencies were observed for those control patients whose primary diagnosis was hypertension but this was considered to be due to selection bias.

Epitopes↗

PubMed1978

Pulmonary function in coal workers with Caplan's syndrome and non-rheumatoid complicated pneumosoniosis.

This retrospective study compares the pulmonary function of 24 coal workers with Caplan's syndrome with that of 36 subjects with non-rheumatoid progressive massive fibrosis (PMF). Allowing for differences in radiographical category, age, years worked underground, and smoking, obstruction to air flow as reflected in the one-second forced expiratory volume, the vital capacity, and the ratio of residual volume to total lung capacity, was significantly less in subjects with Caplan's syndrome. No significant differences in transfer factor were found. These findings may be explained by the different pathological features of the two entities. Selection bias does not appear to be responsible for the differences observed between the groups, but studies designed to eliminate this would be desirable.

Age Factors↗

PubMed1979

Duration of labour with spontaneous onset.

Among 2242 women with spontaneous onset of labour, the median duration of labour for those delivered vaginally was 8 1/4 hours in para 0, 5 1/2 hours in para 1 and 4 3/4 hours in para 2+ mothers. In the parity groups 0, 1 and 2+ 90% had delivered within 16 1/4 hours, 10 1/2 hours and 10 3/4 hours, respectively, while 10% of para 0 labours lasted less than 4 hours, 10% of para 1 labours less than 2 1/4 hours and finally 10% of para 2+ labours less than 2 hours. In the first stage of labour the latent phase (cervical dilatation less than 4 cm), was nearly 2.5 times as long as the active phase (cervical dilatation 4-10 cm). The second stage (cervical dilatation 10 cm-birth) had a median duration of 16 min in para 0 and approximately 10 min in para 1+ mothers. The length of the latent and active phases and the second stage for para 1+ mothers was 60-70% of that of para 0 mothers. In individual mothers there were weak correlations between the length of the phases and stages. For example, the length of the latent phase appeared to be a relatively poor predictor of the length of the active phase of labour. However, selection bias may have weakened these correlations somewhat.

Delivery, Obstetric↗

PubMed2026

Mendelian randomisation for rheumatology: beyond hype-what it's good for, what it can't do, and how to read it critically.

Mendelian randomisation (MR) has become abundant in the literature, with variation in quality and frequent overinterpretation of causality. This creates a problem for clinical readers, reviewers, and editors: some MR studies can sharpen causal thinking, prioritise drug targets, and challenge misleading observational claims, whereas others are little more than automated exposure-outcome scans with causal claims disproportionate to the evidence. MR can strengthen causal inference when randomised trials are impractical and conventional observational studies are vulnerable to confounding, reverse causation, or selection bias. In rheumatology, credible MR can contribute to questions about disease aetiology, modifiable risk factors, therapeutic target validation, adverse-effect anticipation, and phenotype validation. However, its interpretation depends on whether the exposure is plausibly instrumentable, whether the genetic instruments are biologically defensible, whether assumptions are interrogated in ways appropriate to the design, and whether findings are triangulated with clinical, observational, experimental, and mechanistic evidence. Instead of recapitulating all methodological issues of MR, this review aims to help rheumatologists distinguish robust MR from weak or overinterpreted analyses quickly. We provide an accessible framework for reading and triaging MR studies in rheumatology. Papers that use poorly justified instruments, treat medication use as drug-target evidence, interpret genetic liability as diagnosis, rely on mechanical sensitivity analyses, ignore prior evidence or ask no clinically meaningful question can often be passed over by readers. The goal is not to discourage MR in rheumatology, but to raise the standard; useful MR should clarify causal reasoning rather than simply generate another statistically significant association.

Journal Article↗

PubMed1979

The quantitative measurement of depression and anxiety in male alcoholics.

Depression and anxiety have been reported to be commonly associated with alcoholism. Most attempts to clarify this relationship have suffered from a patient selection bias in that only those alcoholics who sought treatment were studied. The authors performed quantitative measurements of depression and anxiety in a group of 48 men referred for treatment solely on the basis of excessive drinking. The prevalence of depression and anxiety as measured by both the Zung and Hamilton scales was lower than that shown in previous studies. The results of this study indicate that problems in young, healthy male alcoholics.

Adult↗

PubMed1978

Urban hospital and rural village smallpox in Bangladesh.

Smallpox mortality at Dacca, Bangladesh Infectious Diseases Hospital during 1972 and 1973 was 46 per cent. To determine if this was the actual rate within the population, data were compared to those collected from village populations in Noakhali District. Age/sex adjusted smallpox mortality for the rural population was 23 per 100 cases as compared to 52 per 100 for the hospital population. Analysis of the difference identified a selection bias of the hospital for severe disease.

Adolescent↗

PubMed2026

Natural Selection Drives Codon Usage Bias in the Mitochondrial Genome of Ligula intestinalis (Linnaeus, 1758) Gmelin, 1790 (Cestoda: Diphyllobothriidea): Insights from Comparative Genomics and Optimal Codon Identification.

Codon usage bias (CUB) is a useful indicator of evolutionary forces shaping mitochondrial genomes. Codon usage bias in mitochondrial genomes of Diphyllobothriidae and especially in Ligula intestinalis was characterized. The roles of natural selection and mutation pressure in framing this bias were evaluated on the basis of 12 protein-coding genes in Diphyllobothriidae. The complete mitogenome (13,725 bp) of L. intestinalis comprises 12 protein-coding genes (PCGs), 22 tRNAs, and two rRNAs, all positioned on the heavy strand, and contains an overall AT content of 66.15%. The mean CAI (0.176), CBI (-0.105), and ENC (45.33) and an evident preference for U-ending codons observed in all examined genes indicate weak CUB. Neutrality, ENC, and PR2 plots consistently demonstrate that natural selection is the predominant force driving CUB and contributes approximately 56% in L. intestinalis and 83% in other Diphyllobothriidea species, with mutation pressure playing a secondary role. Phylogenetic reconstruction supported the monophyly of Diphyllobothriidea, confirmed the paraphyly of Diphyllobothrium as traditionally defined, and placed Ligula and Digramma as sister taxa. These findings clarify the evolutionary constraints governing codon usage in cestode mitogenomes and provide practical resources for codon optimization in heterologous gene expression and genetic studies of this economically important parasite.

Diphyllobothriidea↗