Descriptive analysis of seizures and comorbidities associated with fragile X syndrome.

BACKGROUND: Fragile X syndrome is characterized by a myriad of physical features, behavioral features, and medical problems. Commonly found behavioral features are hyperactivity, anxiety, socialization difficulties, and ASD. There is also a higher incidence than in the general population of strabismus, otitis media, and mitral valve prolapse. In addition, one of the most common medical problems associated with FXS is an increased risk of seizures. A subset of individuals carrying the full mutation of the FMR1 gene and diagnosed with fragile X syndrome (FXS) are reported to experience seizures, mostly during the first 10 years of their life span. METHODS: As part of a larger project to identify genetic variants that modify the risk of seizures, we collected clinical information from 49 carriers with FXS who experienced seizures and 46 without seizures. We compared seizure type and comorbid conditions based on the source of data as well as family history of seizures. RESULTS: We found that the concordance of seizure types observed by parents and medical specialists varied by type of seizure. The most common comorbid condition among those with seizures was autism spectrum disorder (47% per medical records vs. 33% per parent report compared with 19% among those without seizures per parent report); the frequency of other comorbid conditions did not differ among groups. We found a slightly higher frequency of family members who experienced seizures among the seizure group compared with the nonseizure group. CONCLUSION: This study confirms previously reported features of seizures in FXS, supports additional genetic factors, and highlights the importance of information sources, altogether contributing to a better understanding of seizures in FXS.

Predictors of Comorbid Conditions in Women Who Carry an FMR1 Premutation.

Purpose: Women who carry an FMR1 premutation (PM) can experience two well-established PM-associated disorders: fragile X-associated primary ovarian insufficiency (FXPOI, affects ~20-30% carriers) and fragile X-associated tremor-ataxia syndrome (FXTAS, affects ~6-15% carriers); however, emerging evidence indicates that some of these women experience complex health profiles beyond FXPOI and FXTAS. Methods: In an effort to better understand predictors for these comorbid conditions, we collected self-reported medical histories on 413 women who carry an FMR1 PM. Results: There were 22 health conditions reported by at least 9% of women. In an exploratory analysis, 12 variables were tested in logistic regression models for each comorbid condition, including demographic variables, environmental variables, PM-associated factors, and endorsement of depression and/or anxiety. More than half of the comorbid conditions studied were associated with women who self-reported having anxiety. Age, smoking, body mass index (BMI), and depression were also significant predictor variables for specific comorbid conditions. Conclusions: Age, smoking, and BMI were significantly associated with a subset of the comorbid conditions analyzed. Importantly, depression or anxiety were also significantly associated with many of the comorbid health conditions. This work highlights some of the modifiable factors associated with complex health profiles among women with an FMR1 PM.

Identifying susceptibility genes for primary ovarian insufficiency on the high-risk genetic background of a fragile X premutation.

OBJECTIVE: To identify modifying genes that explains the risk of fragile X-associated primary ovarian insufficiency (FXPOI). DESIGN: Gene-based, case/control association study, followed by a functional screen of highly ranked genes using a Drosophila model. SETTING: Participants were recruited from academic and clinical settings. PATIENT(S): Women with a premutation (PM) who experienced FXPOI at the age of 35 years or younger (n = 63) and women with a PM who experienced menopause at the age of 50 years or older (n = 51) provided clinical information and a deoxyribonucleic acid sample for whole genome sequencing. The functional screen was on the basis of Drosophila TRiP lines. INTERVENTION(S): Clinical information and a DNA sample were collected for whole genome sequencing. MAIN OUTCOME MEASURES: A polygenic risk score derived from common variants associated with natural age at menopause was calculated and associated with the risk of FXPOI. Genes associated with the risk of FXPOI were identified on the basis of the P-value from gene-based association test and an altered level of fecundity when knocked down in the Drosophila PM model. RESULTS: The polygenic risk score on the basis of common variants associated with natural age at menopause explained approximately 8% of the variance in the risk of FXPOI. Further, SUMO1 and KRR1 were identified as possible modifying genes associated with the risk of FXPOI on the basis of an untargeted gene analysis of rare variants. CONCLUSIONS: In addition to the large genetic effect of a PM on ovarian function, the additive effects of common variants associated with natural age at menopause and the effect of rare modifying variants appear to play a role in FXPOI risk.

Refining the risk for fragile X-associated primary ovarian insufficiency (FXPOI) by FMR1 CGG repeat size.

PURPOSE: Approximately 20-30% of women with an FMR1 premutation experience fragile X-associated primary ovarian insufficiency (FXPOI); however, current risk estimates based on repeat size only identify women with the midrange of repeats to be at the highest risk. METHODS: To better understand the risk by repeat size, we collected self-reported reproductive histories on 1,668 women and divided them into high-resolution repeat size bins of ~5 CGG repeats to determine a more accurate risk for FXPOI in relation to CGG repeat length. RESULTS: As previously reported, women with 70-100 CGG repeats were at the highest risk for FXPOI using various statistical models to compare average age at menopause and risk of FXPOI, with women with 85-89 repeats being at the highest risk. Importantly, women with <65 repeats or >120 repeats did not have a significantly increased risk for FXPOI compared to women with <45 repeats. CONCLUSION: Using a large cross-section study on 1,668 women, we have provided more personalized risk assessment for FXPOI using high-resolution repeat size bins. Understanding the variability in risk has important implications for family planning and overall health among women with a premutation.

Men with an FMR1 premutation and their health education needs.

Men who carry an FMR1 premutation are at-risk to develop a late-onset neurodegenerative disorder called fragile X-Associated Ataxia/Tremor syndrome (FXTAS). However, little is known about their health informational needs. This qualitative study is the first to describe diagnostic experiences and identify specific health information needs of male premutation carriers. In-depth qualitative interviews were conducted by phone with ten men who carry an FMR1 premutation. Interviews were analyzed using direct content analysis. Saturation was assessed through use of the Comparative Method for Themes Saturation in qualitative interviews (CoMeTS). Five themes were identified: diagnosis experience, sources of health information, desired health information, barriers to obtaining health information, and facilitators to desired health information. Participants desired information about inheritance, symptoms, expectations for disease, and actions available to slow progression. Facilitators to obtaining health information included healthcare provider knowledge, positive experiences with providers, beneficial family dynamics, participating in research, and access to experts. Barriers to obtaining health information included lack of personal knowledge, lack of healthcare provider knowledge, negative experiences with providers, and uncertainty. Addressing the educational needs of men with/at-risk for FXTAS could improve the quality of life of men who carry a fragile X premutation.

Health knowledge of women with a fragile X premutation: Improving understanding with targeted educational material.

Women who carry a fragile X premutation are at risk for at least two major health conditions and for transmitting fragile X syndrome (FXS) to their children. The two health concerns include fragile X-associated primary ovarian insufficiency (FXPOI) and fragile X-associated tremor/ataxia syndrome (FXTAS). The aim of this study was to evaluate whether written educational information about these conditions would increase knowledge and facilitate communication. Women with a premutation (N = 142) completed an online pre-test to assess their knowledge of premutation-associated conditions, and 135 women who provided an address received a booklet titled Women's Health and the Fragile X Premutation. After 3 months, 51.1% completed the post-test. Major gaps in knowledge were related to FXPOI and factors associated with repeat expansion. To determine whether the booklet helped to fill gaps in knowledge, we compared pre- and post-test scores. Scores were significantly increased after receipt of the booklet (p < .05, Wilcoxon signed rank test). Participants answered that the booklet was 'very helpful' (44.6%) or 'somewhat helpful' (38.5%). Twenty-four participants (34.8%) reported using the booklet to explain concepts to family members. Although we found that the booklet provided women with needed information, we found that gaps in knowledge still exist.

Clustering of comorbid conditions among women who carry an FMR1 premutation.

PURPOSE: Emerging evidence indicates that women who carry an FMR1 premutation can experience complex health profiles beyond the two well-established premutation-associated disorders: fragile X-associated primary ovarian insufficiency (FXPOI, affects ~20-30% carriers) and fragile X-associated tremor-ataxia syndrome (FXTAS, affects ~6-15% carriers). METHODS: To better understand premutation-associated health profiles, we collected self-reported medical histories on 355 carrier women. RESULTS: Twenty-two health conditions were reported by at least 10% of women. Anxiety, depression, and headaches were reported by more than 30%. The number of comorbid conditions was significantly associated with body mass index (BMI) and history of smoking, but not age. Survival analysis indicated that women with FXPOI had an earlier age at onset for anxiety and osteoporosis than women without FXPOI. Cluster analysis identified eight clusters of women who reported similar patterns of comorbid conditions. The majority of carriers (63%) fell into three categories primarily defined by the presence of only a few conditions. Interestingly, a single cluster defined women with symptoms of FXTAS, and none of these women had FXPOI. CONCLUSION: Although some women with a premutation experience complex health outcomes, most carriers report only minimal comorbid conditions. Further, women with symptoms of FXTAS appear to be distinct from women with symptoms of FXPOI.

Feasibility of an app-based mindfulness intervention among women with an FMR1 premutation experiencing maternal stress.

BACKGROUND: Women who carry an FMR1 premutation (PM) allele and are mothers of children with fragile X syndrome (FXS) experience elevated maternal stress. In-person mindfulness sessions have been shown to be effective in alleviating maternal stress-related outcomes among mothers of children with intellectual and developmental disabilities. Our prior studies indicate women with a PM are at risk of social anxiety, a potential barrier to in-person mindfulness sessions. AIM: The main goals of this pilot study were to assess feasibility and adherence of an app-based mindfulness training program among mothers of children with FXS and to explore stress, social outcomes, and potential barriers to social support. METHODS: Participants (n = 18) completed questionnaires to assess stress and social anxiety, an app-based mindfulness program, and a semi-structured follow-up interview. RESULTS: Thirteen out of 18 (72%) participants completed the mindfulness program; of those, 10 (77%) found it helpful. Eight out of 18 (44%) participants met criteria for social anxiety and 11 (61%) reported having difficulties reaching out for help when needed. Women with social anxiety and those experiencing barriers to social support were more likely to find the program helpful. CONCLUSIONS: This study provides guidance for future mindfulness-based interventions to alleviate maternal stress in mothers of children with FXS.

FXPOI: Pattern of AGG Interruptions Does not Show an Association With Age at Amenorrhea Among Women With a Premutation.

Fragile X-associated primary ovarian insufficiency (FXPOI) occurs in about 20% of women who carry a premutation allele (55-200 CGG repeats). These women develop hypergonadotropic hypogonadism and have secondary amenorrhea before age 40. A non-linear association with repeat size and risk for FXPOI has been seen in multiple studies women with a premutation: those with a mid-range of repeats are at highest risk (∼70-100 CGG repeats). Importantly, not all carriers with 70-100 repeats experience FXPOI. We investigated whether AGG interruptions, adjusted for repeat size, impacted age at secondary amenorrhea. We have reproductive history information and AGG interruption data on 262 premutation women: 164 had an established age at amenorrhea (AAA) (for some, age at onset of FXPOI) or menopause, 16 had a surgery involving the reproductive system such as a hysterectomy, and 82 women were still cycling at the last interview. Reproductive status was determined using self-report reproductive questionnaires and interviews with a reproductive endocrinologist. For each of these 262 women, FMR1 repeat size and number of AGG interruptions were determined. We confirmed the association of repeat size with AAA or menopause among women with a premutation. As expected, both premutation repeat size and the quadratic form of repeat size (i.e., squared term) were significant in a survival analysis model predicting AAA (p < 0.0001 for both variables). When number of AGG interruptions was added to the model, this variable was not significant (p = 0.59). Finally, we used a regression model based on the 164 women with established AAA to estimate the proportion of variance in AAA explained by repeat size and its squared term. Both terms were again highly significant (p < 0.0001 for both), but together only explained 13% of the variation in AAA. The non-linear association between AAA and FMR1 repeat size has been described in several studies. We have determined that AGG interruption pattern does not contribute to this association. Because only 13% of the variation is described using repeat size, it is clear that further research of FXPOI is needed to identify other factors that affect the risk for FXPOI.

Parental Perspectives on Pharmacological Clinical Trials: a Qualitative Study in Down Syndrome and Fragile X Syndrome.

Research studies focusing on parents' perspectives of pharmacological clinical trials have not kept pace with the number of emerging pharmacologic clinical trials in Down syndrome (DS) and Fragile X syndrome (FXS). Since individuals with DS or FXS have limited cognitive ability to make decisions about their participation in clinical trials, it is important to consider the parents' perspectives and explore the ways in which decisions are made for their children. Using a semi-structured interview, we enrolled 9 parents of a child(ren) with FXS and 15 with a child with DS to analyze their views, experiences, and knowledge of pharmacological clinical trials. Although our study is preliminary in nature, it revealed that parents are generally supportive of pharmacological clinical trials, yet there may be concerns about safety and long-term implications and consideration for their child in the decision process. There is also parental misunderstanding of the objectives of pharmacological clinical trials; thus, it is important for pharmaceutical companies, study investigators, clinicians/medical professionals, and parent advocacy groups to collaborate to provide appropriate and up-to-date educational resources that fully explain the risks and benefits of clinical trials.

Reproductive and gynecologic care of women with fragile X primary ovarian insufficiency (FXPOI).

OBJECTIVE: Approximately 20% of women with a premutation in the FMR1 gene experience primary ovarian insufficiency (POI). We explored diagnostic patterns, frequency of appropriate hormone replacement, obstetric outcomes, fertility treatment, reproductive decisions, and counseling of women with fragile X-associated POI (FXPOI). METHODS: Semistructured interviews with 79 women with FXPOI were conducted by a single interviewer. FMR1 cytosine-guanine-guanine repeat size was determined from a blood, saliva, or buccal sample. RESULTS: The median age of POI onset for women in our study was 33 years. Seventy-two percent of the women had an FMR1 cytosine-guanine-guanine repeat length of 80 to 100. Mean length of time from symptom onset to POI diagnosis was 1.12 years, longer in women with a younger age of POI onset and shorter in women who knew they were carriers. After diagnosis, 52% of women never took hormone therapy, started it years after POI diagnosis, or stopped it before 45 years of age. Forty-nine percent of the women had infertility, but 75% had had at least one genetically related child. Obstetric outcomes were similar to the general population. Forty-six percent of women had a diagnosis of low bone mineral density or osteoporosis, and an additional 19% had never had a bone density assessment. CONCLUSIONS: Women with FXPOI are at significant risk for delayed POI diagnosis and undertreatment with hormone therapy. Although approximately 50% of women had infertility, most were able to conceive at least one child and had no elevated risk of adverse obstetric outcomes.

Improving Health Education for Women Who Carry an FMR1 Premutation.

Women who carry an FMR1 (i.e., fragile X) premutation have specific health risks over their lifetime. However, little is known about their experience understanding these risks and navigating their health needs. The aim of this study was to use qualitative analysis to uncover both barriers and facilitators to personal healthcare using a framework of the Health Belief Model. Five focus groups were conducted with a total of 20 women who carry the FMR1 premutation using a semi-structured discussion guide. All sessions were transcribed verbatim and independently coded by two researchers. The coders used a deductive - inductive approach to determine the prominent themes related to the participants' experiences seeking healthcare for premutation-related conditions. Salient barriers to personal healthcare included difficult clinical translation of research findings, lack of knowledge among healthcare providers and among the women themselves, different priorities, and shortage of premutation-specific support and targeted educational materials. Facilitators included family members, national and community support organizations, research studies, compassionate physicians, and other premutation carriers. Addressing barriers to personal healthcare through up-to-date educational materials can help diminish misperceptions regarding health risks. Targeted educational materials will aid in information sharing and awareness for women who carry the FMR1 premutation and their physicians.

Depression and anxiety symptoms among women who carry the FMR1 premutation: impact of raising a child with fragile X syndrome is moderated by CRHR1 polymorphisms.

The fragile X mental retardation gene, FMR1, contains a polymorphic CGG repeat in the 5'-untranslated region of exon 1. Once unstable, this repeat is capable of expansion across generations. Women who carry a premutation allele (55-199 repeats) are at risk of passing on a full mutation allele (>200 repeats) to their offspring. A full mutation leads to the most common form of inherited intellectual disability, fragile X syndrome (FXS). Mounting evidence suggests that premutation carriers may be vulnerable to symptoms of anxiety and depression. The goal of this study was to test the hypothesis that among women who carry a premutation, the stress of raising a child with FXS would be moderated by genetic factors influencing endogenous cortisol responses, which could in turn modulate anxiety and depression symptoms. To this end, we genotyped single nucleotide polymorphisms (SNPs) at the corticotrophin releasing hormone receptor 1 locus (CRHR1) in 460 women. Participants completed self-report questionnaires assessing symptoms of depression [Centers for Epidemiological Studies Depression Scale (CESD)], anxiety [State-Trait Anxiety Inventory (STAI) and Social Phobia and Anxiety Inventory (SPAI)], and mood [Positive and Negative Affect Schedule (PANAS)]. Results indicate a statistically significant interaction between CRHR1 genotype and the status of raising a child with FXS to predict social anxiety symptoms reported on the SPAI (rs7209436, P = 0.0001). Our data suggest that genetic variants in CRHR1 that associate with differential cortisol activation may also modulate levels of anxiety related to the stress of raising a child with FXS among women who carry an FMR1 premutation.

Diagnosis of fragile X syndrome: a qualitative study of African American families.

Fragile X syndrome (FXS) is an inherited genetic condition with critical consequences to the proband and family members at all levels in the generations. Although evidence demonstrates that the rates of diagnosis for FXS are the same in all racial groups, age of diagnosis in African American children has been reported to occur later than in Caucasian children. Additionally, African American families are seriously under-represented in existing FXS research studies. As such, it is important to understand the possible disparities in the underlying factors to receiving a diagnosis in African American families with FXS. Herein, a qualitative approach was adopted to describe the overall FXS diagnosis experiences (pre-diagnosis, diagnosis, and post-diagnosis stages) of a convenience sample of 10 African American mothers. We identified three major findings among our participants: (1) FXS testing is not ordered immediately once a parent expresses concerns of developmental delays to the pediatricians, (2) the diagnosis is sometimes delivered in an insensitive manner with information often being outdated and unbalanced towards negative aspects, (3) communication issues among family members exists once the diagnosis is discovered. Although these qualitative data may not be representative of the whole group, these findings have significant implications for genetic counseling and our understanding in providing support and advocacy for African American families with FXS.

Neuropsychological findings from older premutation carrier males and their noncarrier siblings from families with fragile X syndrome.

OBJECTIVE: Carriers of the FMR1 premutation allele are at a significantly increased risk for a late-onset neurodegenerative disorder, fragile X-associated tremor/ataxia syndrome (FXTAS). The primary features of FXTAS are late-onset intention tremor and gait ataxia. Previous reports have shown global deficits in neuropsychological measures among males with FXTAS, particularly those related to executive functioning. The purpose of this study was to investigate the neuropsychological profile among older males with the premutation who are at risk for FXTAS. METHOD: Premutation carriers, 66 with motor symptoms and 23 without, and 18 noncarrier siblings were recruited from pedigrees diagnosed with fragile X syndrome, all over age 50. Subjects were examined with a neurological test battery to identify symptoms of FXTAS and a neuropsychological test battery to investigate cognitive and behavioral profiles. Linear regression and ANCOVA were used to determine the effect of the premutation on outcome measures adjusting for age and education. RESULTS: We identified a significant decrease in scores of general intelligence and a marginally significant decrease in scores of logical memory among premutation carrier males with motor symptoms compared to the noncarrier male siblings. We did not identify deficits in executive functioning in our sample of premutation carrier males with motor symptoms. CONCLUSIONS: Similar to other reports, we found that the FMR1 premutation is associated with deficits in general intelligence and memory among older males with symptoms of FXTAS. However, our results differed in that we found no evidence of premutation-associated executive dysfunction. We provide possible explanations for this difference.

No evidence for a difference in neuropsychological profile among carriers and noncarriers of the FMR1 premutation in adults under the age of 50.

The 5' untranslated region of the fragile X mental retardation gene, FMR1, contains a polymorphic CGG repeat. Expansions of this repeat are associated with a spectrum of disorders. Full mutation alleles, repeats >or= 200, are associated with fragile X syndrome. Premutation alleles, repeats of approximately 55-199, are associated with a tremor-ataxia syndrome most commonly in older males and primary ovarian insufficiency in females. However, the neuropsychological impact of carrying a premutation allele is presently unclear in younger adults. In this study, we analyzed neuropsychological scores for 138 males and 506 females ascertained from the general population and from families with a history of fragile X syndrome. Subjects were age 18-50 years and had varying repeat lengths. Neuropsychological scores were obtained from measures of general intelligence, memory, and executive functioning, including attention. Principal component analysis followed by varimax rotation was used to create independent factors for analysis. These factors were modeled for males and females separately via a general linear model that accounted for correlation among related subjects. All models were adjusted for potential confounders, including age at testing, ethnicity, and household income. Among males, no repeat length associations were detected for any factor. Among females, only a significant association with repeat length and self-report attention (p < 0.01) was detected, with premutation carriers self-reporting significantly more attention-related problems compared to noncarriers. No significant interactions between repeat length and age were detected. Overall, these results indicate the lack of a global neuropsychological impact of carrying a premutation allele among adults under the age of 50.

Investigation of phenotypes associated with mood and anxiety among male and female fragile X premutation carriers.

The fragile X disorder spectrum, due to a CGG expansion in FMR1, includes fragile X syndrome (>200 repeats) and the premutation-associated disorders of ovarian insufficiency and tremor/ataxia syndrome (approximately 55-199 repeats). Altered neurobehavioral profiles including variation of phenotypes associated with mood and anxiety may be expected among younger premutation carriers given this spectrum of disorders. However, previous studies have produced conflicting findings, providing the motivation to examine these phenotypes further. We investigated measures of mood and anxiety in 119 males and 446 females age 18-50 ascertained from families with a history of fragile X syndrome and from the general population. Scores were analyzed using a linear model with repeat length as the main predictor, adjusting for potential confounders. Repeat length was not associated with anxiety, but was marginally associated with depression and negative affect in males and negative affect only in females. These results suggest that premutation carriers may be at risk for emotional morbidity; however, phenotypic differences were subtle and of small effect size.

Fragile X-associated primary ovarian insufficiency: evidence for additional genetic contributions to severity.

The fragile X mental retardation gene (FMR1) contains a CGG repeat sequence in its 5' untranslated region that can become unstable and expand in length from generation to generation. Alleles with expanded repeats in the range of approximately 55-199, termed premutation alleles, are associated with an increased risk for fragile-X-associated primary ovarian insufficiency (FXPOI). However, not all women who carry the premutation develop FXPOI. To determine if additional genes could explain variability in onset and severity, we used a random-effects Cox proportional hazards model to analyze age at menopause on 680 women from 225 families who have a history of fragile X syndrome and 321 women from 219 families from the general population. We tested for the presence of a residual additive genetic effect after adjustment for FMR1 repeat length, race, smoking, body mass index, and method of ascertainment. Results showed significant familial aggregation of age at menopause with an estimated additive genetic variance of 0.55-0.96 depending on the parameterization of FMR1 repeat size and definition of age at menopause (P-values ranging between 0.0002 and 0.0027). This is the first study to analyze familial aggregation of FXPOI. This result is important for proper counseling of women who carry FMR1 premutation alleles and for guidance of future studies to identify additional genes that influence ovarian insufficiency.