Separate influences of birth order and gravidity/parity on the development of systemic sclerosis

Connexin 37, 40, 43 and Pannexin 1 Expression in the Gastric Mucosa of Patients with Systemic Sclerosis

Systemic sclerosis (SSc) is an autoimmune disease characterized by fibrosis of the skin and internal organs. Although its pathogenesis is not fully understood, connexins (Cxs) and pannexins (Panx) could be involved in the process of fibrosis. We analyzed the protein expression of Cx37, Cx40, Cx43, and Panx1 in the gastric mucosa of patients with SSc and healthy volunteers, using immunofluorescence staining. Protein levels of Cx37 were slightly increased, while the levels of Cx40 were significantly decreased in the lamina propria of the gastric mucosa of SSc patients compared to the controls. The changes were proportional to SSc severity, with the most prominent changes found in patients with severe diffuse cutaneous SSc. No differences in Cx43 or Panx1 levels were found between the analyzed groups of samples. The lack of changes in Cx43 expression, which has been previously associated with fibrosis, could be due to the weak expression of Cx43 in the gastric mucosa in general. Further studies on full-thickness gastric biopsies containing muscle layers and animal SSc models are needed to fully elucidate the role of Cxs and Panxs in SSc-associated fibrosis.

Primary biliary cholangitis: primary autoimmune disease or primary secretory defect

INTRODUCTION

Primary biliary cholangitis (PBC) is a chronic cholestatic liver disease characterized by the immune-mediated destruction of small and medium intrahepatic bile ducts, involving predominantly females. PBC has long been described as an autoimmune liver disease, also because it is very often associated with many autoimmune conditions. More recently, another pathogenic mechanism exploring the damage of cholangiocytes has been hypothesized, i.e. a defect in the biliary umbrella which is physiologically responsible for the exchange of the ions Cl- and HCO3- and maintains the integrity of glycocalyx. To provide a state-of-the-art analysis of this topic, a systematic review of literature in PubMed, Scopus, and Science Direct was conducted (inclusive dates: 1986-2023).

AREA COVERED

Although the etiology remains unknown, pathogenesis consists of a complex immune-mediated process resulting from a genetic susceptibility. PBC can be triggered by an immune-mediated response to an autoantigen, which leads to a progressive destruction of bile ducts and eventually to a progressive fibrosis with cirrhosis. The defect in the 'bicarbonate umbrella' acts as a protection against the toxic hydrophobic bile acids, leading to a toxic composition of bile.

EXPERT OPINION

This review offers a summary of the current knowledge about the pathogenesis of PBC, indicating that this is probably based on the mutual relationship between the immune insult and the unbalanced secretory mechanisms.

Anti-RBD IgA and IgG Response and Transmission in Breast Milk of Anti-SARS-CoV-2 Vaccinated Mothers

The appearance of the severe acute respiratory syndrome virus-2 (SARS-CoV-2) has had a significant impact on the balance of public health and social life. The data available so far show that newborns and young children do not develop severe forms of COVID-19, but a small proportion of them will still need hospitalization. Even though young children represent an important vector of the infection, vaccination at such a young age was not yet considered. Thus, the question of whether potentially protective antibodies against SARS-CoV-2 could be provided to them via breast milk or across the placenta, as “passive immunity”, still stands. Materials and Methods: Between January–July 2021, we have conducted a prospective study that aimed to measure the immunoglobulin (Ig) A and IgG anti-SARS-CoV-2 titers in the breast milk of 28 vaccinated lactating mothers, sampled at 30 and 60 days after the second dose of the anti-SARS-CoV-2 Pfizer or Moderna mRNA vaccines. Anti-RBD reactive IgA and IgG antibodies were detected and quantified by a sandwich enzyme-linked immunosorbent assay. Results: Anti-RBD IgA and IgG were present in all breast milk samples, both in the first and in the second specimens, without a significant difference between those two. The anti-RBD IgA titers were approximately five-times higher than the anti-RBD IgG ones. The anti-RBD IgA and IgG titers were correlated with the infants’ age, but they were not correlated with the vaccine type or mother’s age. The anti-RBD IgA excreted in milk were inversely correlated with the parity number. Conclusions: Anti-SARS-CoV-2 IgA and IgG can be found in the milk secretion of mothers vaccinated with mRNA vaccines and, presumably, these antibodies should offer protection to the newborn, considering that the antibodies’ titers did not decrease after 60 days. The antibody response is directly proportional to the breastfed child’s age, but the amount of anti-RBD IgA decreases with the baby’s rank. The antibody response did not depend on the vaccine type, or on the mother’s age.

Pregnancy-associated risk factors and incidence of systemic sclerosis in primiparous women: A nationwide population-based cohort study

OBJECTIVES

To evaluate the pregnancy-related risk factors and incidence rate (IR) of systemic sclerosis (SSc) in primipara using the Health Insurance Review and Assessment database, covering all medical claims in South Korea.

METHODS

From the database, 2,260,952 primipara aged 18-49 years from 2008 to 2018 were identified. The patients were followed up after their index delivery until December 2019. A Cox proportional hazard analysis was performed to identify the association of pregnancy-related factors with SSc development.

RESULTS

The SSc IR was 0.62 cases per 100,000 patient-years. Primipara had a higher risk of developing SSc after 3 years postpartum than in the first 3 years of delivery (OR = 1.98, 95% CI: 1.36-2.78, p < .001). A multivariate analysis showed that older age (35-49 years) (HR = 2.14, 95% CI: 1.05-4.35, p = .037) and a Caesarean section (CS) (HR = 1.86, 95% CI: 1.10-3.15, p = .021) are risk factors for SSc. At 3 years postpartum, CS (HR = 2.97, 95% CI: 1.39-6.32, p = .005) and a female infant (HR = 2.28, 95% CI: 1.11-4.71, p = .026) were associated with SSc development.

CONCLUSION

Having a CS, late childbirth, and a female infant are the risk factors for SSc in primipara. This study establishes the IR of SSc in primipara.

Women with Recurrent Pregnancy Loss More Often Have an Older Brother and a Previous Birth of a Boy: Is Male Microchimerism a Risk Factor?

Known etiologic factors can only be found in about 50% of patients with recurrent pregnancy loss (RPL). We hypothesized that male microchimerism is a risk factor for RPL and aimed to explore whether information on family tree and reproductive history, obtained from 383 patients with unexplained RPL, was supportive of this hypothesis. The male:female sex ratio of older siblings was 1.49 (97:65) in all RPL patients and 1.79 (52:29) in secondary RPL (sRPL) patients, which differed significantly from the expected 1.04 ratio (p = 0.027 and p = 0.019, respectively). In contrast, the sex ratio of younger siblings was close to the expected ratio. Sex ratio of the firstborn child before sRPL was 1.51 (p = 0.026). When combined, 79.1% of sRPL patients had at least one older brother, a firstborn boy, or both. This differed significantly from what we expected based on the distribution of younger siblings and a general 1.04 sex ratio of newborns (p = 0.040). We speculate whether (s)RPL patients possibly acquired male microchimerism from older brother(s) and/or previous birth of boy(s) by transplacental cell trafficking. This could potentially have a detrimental impact on their immune system, causing a harmful response against the fetus or trophoblast, resulting in RPL.

Scleroderma in Cairns: an epidemiological study

BACKGROUND

Systemic sclerosis (SSc) refers to an autoimmune fibrosing disorder with high disease burden and mortality. The prevalence of 23/100 000 in South Australia (SA) is among the highest documented, but anecdotally it is higher still in Cairns.

AIMS

To ascertain the prevalence of SSc in Cairns and surrounding regions, and to compare the demographic and clinical characteristics of patients with SSc in Cairns with those in SA.

METHODS

Patients with SSc in Cairns were ascertained through hospital records and by referrals from specialist physicians in the region. These patients were interviewed and completed a structured questionnaire. Their physical findings and autoantibodies were recorded. These patients were compared with the SA patients enrolled in the Australian Scleroderma Cohort Study.

RESULTS

A total of 81 patients was identified in Cairns, giving an estimated cross-sectional prevalence of 33.7/100 000. Among 65 patients interviewed in Cairns, 23 were born in Cairns, 16 had migrated to Cairns to ameliorate their Raynaud phenomenon and 26 for other reasons. The clinical features in both cohorts were similar, although Cairns had a lower prevalence of digital ulcers (30.8% vs 46.6%; odds ratio (OR) = 0.5035, 95% confidence interval (CI): 0.2839-0.8929, P = 0.0271) and higher prevalence of calcinosis (29.2% vs 17.0%; OR = 2.005, 95% CI: 1.055-3.382).

CONCLUSIONS

The higher prevalence of SSc in Cairns is partly, but not completely, due to migration. Differences in clinical features are not entirely explained by the warmer climate. There is a need for greater rheumatologic services in the Cairns region.

Birth Characteristics and Risk of Early-Onset Synovial Sarcoma

BACKGROUND

Synovial sarcoma is a rare cancer with peak incidence in the young adult period. Despite poor outcomes of this aggressive cancer, there is little epidemiologic research addressing its etiology.

METHODS

We collected birth characteristic data on synovial sarcoma cases born during 1978-2015 and diagnosed during 1988-2015 in California (n = 244), and 12,200 controls frequency-matched on year of birth. We also constructed a dataset of cancer cases in siblings of sarcoma subjects to assess familial risk.

RESULTS

In multivariable logistic regression analyses, synovial sarcoma was more frequent in Hispanics compared with non-Hispanic whites [OR, 1.48; 95% confidence interval (CI), 1.06-2.08]. Higher birth weight was a risk factor in Hispanics; each 500 g increase in birth weight was associated with a 22% increase in disease risk (OR, 1.22; 95% CI, 1.00-1.48). Also, a strong role for birth order was suggested, with highest risk for the first born (second child compared with first: OR, 0.61; 95% CI, 0.44-0.84; third or later compared with first: OR, 0.53; 95% CI, 0.36-0.77). Siblings of patients with synovial sarcoma did not display elevated cancer incidence, suggesting the low likelihood that strong familial predisposition alleles play a significant role in this disease.

CONCLUSIONS

The associations with birth weight and birth order suggest that nutritional, developmental, and environmental factors may play a role in the etiology of synovial sarcoma.

IMPACT

Further epidemiologic research on synovial sarcoma should evaluate epigenetic and developmental mechanisms and the formation of the archetypical t(X;18) translocation that defines this disease.

Exacerbations of autoimmune diseases during pregnancy and postpartum

Autoimmune diseases represent a complex heterogeneous group of disorders that occur as a results of immune homeostasis dysregulation and loss of self-tolerance. Interestingly, more than 80% of the cases are found among women at reproductive age. Normal pregnancy is associated with remarkable changes in the immune and endocrine signaling required to tolerate and support the development and survival of the placenta and the semi-allogenic fetus in the hostile maternal immune system environment. Gravidity and postpartum represent an extremely challenge period, and likewise the general population, women suffering from autoimmune disorders attempt pregnancy. Effective preconception counseling and subsequent gestation and postpartum follow-up are crucial for improving mother and child outcomes. This comprehensive review provides information about the different pathways modulating autoimmune diseases activity and severity, such as the influence hormones, microbiome, infections, vaccines, among others, as well as updated recommendations were needed, in order to offer those women better medical care and life quality.

The association between reproductive factors and systemic sclerosis in Chinese women: A case-control study and meta-analysis

AIM

To examine the associations between female menstrual or reproductive factors and the development of systemic sclerosis (SSc) in China.

METHODS

In this hospital-based case-control study, for each subject, data on reproductive and menstrual factors such as number of births, abortions, and age at menarche were obtained by structured questionnaire. Risk estimates, measured by the odds ratio (OR) and 95% confidence interval (CI), were obtained by unconditional logistics regression. Furthermore, meta-analysis was performed and pooled OR with 95% CI for the number of pregnancies and abortions were calculated.

RESULTS

There were 166 SSc and 392 female controls seen during the study period. The results showed women with late menarche age (≥17 years) were less likely than those with earlier age at menarche to develop SSc (OR 0.347, 95% CI 0.174-0.693) and compared with women without abortion, women with abortion (1 time) were at reduced risk of developing SSc (P = .036). After adjusting for potential confounders such as occupation and body mass index (BMI), late age at menarche (≥17 years) was associated with a decreased risk of SSc (OR 0.187, 95% CI 0.068-0.513), but abortions were not significantly related to SSc. The meta-analysis revealed there was no association between SSc and abortions or number of pregnancies. No significant publication bias was observed (P > .05).

CONCLUSION

Late age at menarche was associated with a reduced risk of SSc but abortion may not be an independent risk factor for SSc. Further investigations are required to verify our findings.

Risk factors for the development of systemic sclerosis: a systematic review of the literature

OBJECTIVES

Although numerous studies have investigated the roles of various genetic, epigenetic and environmental factors that may impact its aetiology, SSc is still regarded as an idiopathic disease. Given that there is significant heterogeneity in what has been proposed to influence the development of SSc, this systematic review was conducted to assess the impacts of different factors on the aetiology of scleroderma.

METHODS

The search was performed in the PubMed, CINAHL and SCOPUS databases on 17 May 2017. Any study that made explicit reference to scleroderma or SSc that had information about the risk factors or epidemiology of the disease was included. The extracted outcome variables were prevalence, gender preponderance, geographical distribution, family history and various proposed environmental risk factors.

RESULTS

One thousand five hundred and seventy-four articles were screened for eligibility. Thirty-four articles were eligible for the systematic literature review.

CONCLUSION

Age between 45 and 64 years, female sex, positive family history and exposure to silica were found to be risk factors. There were conflicting findings regarding the impact of exposure to organic solvents and microchimerism. No relationship between infectious agents, alcohol consumption or cigarette smoking and the development of SSc was identified.

Environmental Basis of Autoimmunity

The three common themes that underlie the induction and perpetuation of autoimmunity are genetic predisposition, environmental factors, and immune regulation. Environmental factors have gained much attention for their role in triggering autoimmunity, with increasing evidence of their influence as demonstrated by epidemiological studies, laboratory research, and animal studies. Environmental factors known to trigger and perpetuate autoimmunity include infections, gut microbiota, as well as physical and environmental agents. To address these issues, we will review major potential mechanisms that underlie autoimmunity including molecular mimicry, epitope spreading, bystander activation, polyclonal activation of B and T cells, infections, and autoinflammatory activation of innate immunity. The association of the gut microbiota on autoimmunity will be particularly highlighted by their interaction with pharmaceutical agents that may lead to organ-specific autoimmunity. Nonetheless, and we will emphasize this point, the precise mechanism of environmental influence on disease pathogenesis remains elusive.

Pregnancy and primary biliary cirrhosis: a case-control study

A very critical feature in women's health is the identification of risk factors for pregnancy and adverse fetal outcome. Primary biliary cirrhosis is an autoimmune disease of the liver that predominantly affects older women. However, the serologic onset of this disease appears to precede clinical manifestations by many years. The goal of this case controlled study was to analyze fertility in primary biliary cirrhosis (PBC) and investigate the outcome of pregnancy, and the influence of pregnancy on the course of the disease. The study included 233 consecutive female patients with PBC seen between 1987 and 2012. Among them, 186 had at least one conception and were matched for age with a 1:2 group of controls (367 healthy women with at least one conception in their life). PBC patients experienced 507 pregnancies as opposed to 700 pregnancies among controls (mean 1.91 vs 2.73, p < 0.05). The two groups' life history was similar in terms of miscarriages, voluntary interruptions of pregnancy, and term and preterm deliveries. The rates for one or more cesarean deliveries were lower for PBC patients (5.7 vs 11.7 %, p < 0.05). Pruritus during pregnancy was recorded in 15 pregnancies involving 13 PBC patients (3.0 %) and none of the controls. Perinatal and postnatal deaths and complications at childbirth were only recorded in the PBC patients, involving a total of 11 babies (2.7 %, p < 0.05). Eight pregnancies occurred after PBC was diagnosed in six patients, all of which had a favorable course at term, with no complications at childbirth. Ursodeoxycholic acid was continued during pregnancy and no exacerbation of the disease was observed. In conclusion, successful completion of pregnancy is a realistic expectation for PBC patients, though pregnancy and delivery must be monitored for the potentially higher than normal risk of childbirth complications.

Parental influence on systemic sclerosis

OBJECTIVE

To examine parental influence on the development of systemic sclerosis (SSc; scleroderma). We designed 3 studies: mitochondrial inheritance, birth order (a possible surrogate marker for microchimerism), and paternal age at conception (a possible surrogate for telomere erosion) to examine their association with development of SSc.

METHODS

SSc was defined by International Classification of Diseases, Ninth and Tenth Revision codes (ICD-9 710.1 and ICD 10 M34.0, M34.1, and M34.9) and identified from statewide discharge data, University of Utah Health Science Center Enterprise Data Warehouse (UUHSC), and death certificates that were linked to the Utah Population Database (UPDB) for analysis. Mitochondrial inheritance was evaluated by conditional logistic regression and population attributable risk using familial standardized incidence ratio as the covariate. Chi-square test and logistic regression were used to evaluate birth order and maternal/paternal age at conception of the SSc proband.

RESULTS

We found 1,947 unique SSc patients from UUHSC and UPDB. We selected 5 controls per case (n = 9,115), matched by birth year and sex. Mitochondrial inheritance analysis indicated no evidence to suggest SSc was associated with mitochondrial inheritance. Birth order and maternal/paternal age at conception analysis results show that they also do not significantly affect SSc development.

CONCLUSION

Results suggest that although heritable risk of SSc is observed, mitochondrial inheritance, birth order, and parental age are not likely responsible for pathogenesis.

Infancy narcolepsy: Streptococcus infection as a causal factor

Streptococcal infections are suggested as a risk factor for narcolepsy. This hypothesis is supported by the presence of anti-streptolysin antibodies in 65% of patients with narcolepsy. These infections are associated with the activation of general immunity and concomitant increased permeability of blood–brain barrier after T cell activation during inflammation and fever.

It has also been shown a significant association between birth order and narcolepsy in genetically susceptible patients, with positivity for HLA-DQB1⁎0602 allele. Watson and colleagues showed a significant association between birth order and narcolepsy in genetically susceptible patients, with positivity for HLA-DQB1⁎0602 allele. In that study, the disease was predominant in young children cases compared to controls.

We report here the case of a child diagnosed with narcolepsy with cataplexy, positivity for the HLA-DQB1⁎0602 and previous history of streptococcal infection.

Perinatal risk factors for future SLE: a population-based nested case-control study

OBJECTIVE

To investigate the association between perinatal characteristics and the offspring's risk of lupus using population-based registers in Sweden.

METHODS

We conducted a nested case-control study, identifying systemic lupus erythematosus (SLE) cases from the National Patient Register and controls sampled from the general population matched on birth year, sex, and residential county. We obtained data on the mother's health and age during pregnancy and characteristics of labor and delivery from the Medical Birth Register (births from 1973 through 2008) for cases and controls. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using conditional logistic regression models overall and separately for males and females.

RESULTS

We identified 774 cases and 3337 controls. Age at which SLE was first observed ranged from 0 to 36 years old. High birth weight was not a risk factor for SLE and did not differ by sex. Males had a 2.4-fold increased odds of SLE if born preterm (<37 weeks; OR = 2.41; 95% CI 1.09, 5.36). Birth order was significantly associated with SLE, particularly among females (first born vs. not OR = 0.77, 95% CI 0.64, 0.94; continuous birth order OR = 1.12. 95% CI 1.02, 1.24).

CONCLUSION

Being born first was associated with reduced odds of SLE and the odds of SLE increased by 12% for every additional birth. Preterm birth was associated with increased odds in males only. Unlike previous work, high birth weight was not a risk factor for SLE.

Is pregnancy a risk factor for rheumatic autoimmune diseases?

PURPOSE OF REVIEW

To review the association of pregnancy with the risk of subsequent development of rheumatic autoimmune diseases in women, including rheumatoid arthritis (RA), systemic lupus erythematosus, and scleroderma.

RECENT FINDINGS

There is a small but growing literature related to the risk of autoimmune rheumatic disease in association with pregnancy history. However, results conflict both in terms of the direction and magnitude of risk of disease in relationship to prior pregnancy history. Although anecdotal evidence tends to favor the premise that pregnancy is protective against certain diseases, such as RA, the heterogeneity of results precludes the ability to confirm an association in either direction. There is indication that time elapsed since pregnancy may influence risk, with the postpartum year being of particular relevance.

SUMMARY

To date, a clear pattern has not emerged regarding pregnancy and the future risk of autoimmune rheumatic diseases. This topic requires greater study, and given the strong female preponderance of these diseases, future research efforts should seek to resolve this important issue.

Mood disorders and parity - a clue to the aetiology of the postpartum trigger

BACKGROUND

Episodes of postpartum psychosis have been associated with first pregnancies in women with bipolar I disorder. It is unclear, however, if the effect extends to episodes at other times in relation to childbirth and to women with other mood disorders such as major depression and bipolar II disorder. This primiparity effect, which is also seen in other pregnancy related conditions such as pre-eclampsia, is a potentially important clue to the aetiology of childbirth related mood episodes.

METHODS

Participants were interviewed and case notes reviewed. Best-estimate diagnoses were made according to DSM-IV criteria. Data on the occurrence of episodes in pregnancy and the postpartum were available on 3345 full term deliveries from 1667 participants, 934 with bipolar I disorder (BD-I), 278 with bipolar II disorder (BD-II) and 455 with recurrent major depression (RMD).

RESULTS

Onsets of psychosis/mania within 6 weeks of childbirth were overrepresented in primiparae (p=0.007) with BD-I. Although primiparity was not associated with perinatal bipolar depression, there was an association with the onset of depression within 6 weeks in women with RMD (p=0.035). Whilst women experiencing a postpartum episode were less likely to go on to have further children, this did not account for the association with primiparity.

LIMITATIONS

Data were collected retrospectively. Information on pharmacological treatment was not available.

CONCLUSIONS

Primiparity is associated not only with postpartum psychosis/mania in BD-I, but also with postpartum depression in RMD. Psychosocial factors and biological differences between first and subsequent pregnancies may play a role and are candidates for examination in further studies.

Genetics of systemic sclerosis: an update

Systemic sclerosis (SSc) is an autoimmune disease characterized by vasculopathy, immune cell activation, and fibrosis of the skin and internal organs. Over the past few years, a role for genetics in the susceptibility for SSc has been established. This review aims to provide an update on the progress made in the past year or so within the field of SSc genetics research. This year has been of particular interest due to the publication of a large genome-wide association study, further investigations into gene-gene interactions, and the tendency to validate genetic results in functional models.

Birth order and narcolepsy risk among genetically susceptible individuals: a population-based case-control study

BACKGROUND

Birth order may play a role in autoimmune diseases and early childhood infections, both factors implicated in the etiology of narcolepsy. We investigated the association between birth order and narcolepsy risk in a population-based case-control study in which all study subjects were HLA-DQB1*0602 positive.

METHODS

Subjects were 18-50 years old, residents of King County, Washington, and positive for HLA-DQB1*0602. Birth order was obtained from administered interviews. We used logistic regression to generate odds ratios adjusted for income and African American race.

RESULTS

Analyses included 67 cases (mean age 34.3 [SD=9.1], 70.2% female) and 95 controls (mean age 35.1 [SD=8.8], 58.1% female). Associations for birth order were as follows: first born (cases 38.8% vs. controls 50.2%, OR=1.0; reference), second born (cases 29.9% vs. controls 32.9%, OR=1.6; 95% CI 0.7, 3.7), and third born or higher (cases 31.3% vs. controls 16.8%, OR=2.5; 95% CI 1.0, 6.0). A linear trend was significant (p<0.05). Sibling number, sibling gender, having children, and number of children did not differ significantly between narcolepsy cases and controls.

CONCLUSIONS

Narcolepsy risk was significantly associated with higher birth order in this population-based study of genetically susceptible individuals. This finding supports an environmental influence on narcolepsy risk through an autoimmune mechanism, early childhood infections, or both.

Pre-disease pregnancy complications and systemic sclerosis: pathogenic or pre-clinical?

The fetal microchimerism theory for the pathogenesis of systemic sclerosis (SSc) has compelling biologic support, including the female predominance of the disease, the mean age of onset after childbearing years, similarities between diffuse cutaneous SSc and graft-versus-host disease, as well as the detection of microchimeric cells in peripheral blood and skin of SSc patients. The previous issue of Arthritis Research and Therapy presents findings of a positive association between pregnancy complications and future diagnosis of SSc in parous women. Before interpreting the results of this epidemiologic study as support for fetal microchimerism, however, other theories for the observed associations must be considered.