Quality of life assessment in a sample of patients affected by Prader-Willi syndrome

Perception of Social and Educational Quality of Life of Minors Diagnosed with Rare Diseases: A Systematic Review and Meta-Analysis

This study explores the perception of social and educational quality of life in minors with rare diseases (RDs). Two meta-analyses were performed, applying the random effects model. Results: Regarding the social Quality of Life, the meta-sample consisted of k = 40 samples, with a total population of 1943 children (mean age = 9.42 years), of whom 687 (35.3%) were girls, 615 (31.4%) were boys and 641 (33%) did not report their sex. The effect size was large (mean size = 7.68; p < 0.000; 99% Confidence Interval; lower limit = 7.22; upper limit = 8.14). The results of the meta-regression and model analysis showed the importance of the measurement instrument (Paediatric Quality-of-Life Inventory and Prototypes of the Quality of life) and the dissimilarity of perception among caregivers. The nationality and the type of RD were not relevant. With respect to the educational Quality of Life, the meta-sample consisted of k = 19 samples, with 699 minors (mean age = 10.3 years), of whom 266 (38%) were girls, 242 (34.6%) were boys and 191 (27.4%) did not report their sex. The effect size was large (mean size = 7.15; p < 0.000; 99% CI; lower limit = 6.35; upper limit = 7.94). The meta-regression and comparison of models showed that the type of RD was essential. The measurement instrument was a moderating variable, especially the Parent version Paediatric Quality-of-Life Inventory. This study reveals the need for further research on RDs and their social−educational effects.

Progressive resistance training in young people with Prader-Willi syndrome: protocol for a randomised trial (PRESTO)

INTRODUCTION

Preliminary evidence suggests that progressive resistance training may be beneficial for people with Prader-Willi Syndrome (PWS), a rare genetic condition that results in muscle weakness and low muscle tone.To establish whether community-based progressive resistance training is effective in improving the muscle strength of people with PWS; to determine cost-effectiveness; and, to complete a process evaluation assessing intervention fidelity, exploring mechanisms of impact, understanding participant experiences and identifying contextual factors affecting implementation.

METHODS AND ANALYSIS

A multisite, randomised controlled trial will be completed. Sixty participants with PWS will be randomised to receive either progressive resistance training (experimental) or non-progressive exercise (placebo control). Participants will be aged 13 to 60 years, be able to follow simple instructions in English and have no contraindications to performing progressive resistance training. The experimental group will complete progressive resistance training two times weekly for 24 weeks supervised by an exercise professional at a community gym. The control group will receive all aspects of the intervention except progressive overload. Outcomes will be assessed at week 25 (primary endpoint) and week 52 by a blinded assessor. The primary outcome is muscle strength assessed using one repetition maximum for upper limb and lower limb. Secondary outcomes are muscle mass, functional strength, physical activity, community participation, health-related quality of life and behaviour. Health economic analysis will evaluate cost-effectiveness. Process evaluation will assess safety and intervention fidelity, investigate mechanism of impact, explore participant experiences and identify contextual factors affecting implementation. Data collection commenced in February 2020 and will conclude in September 2023.

ETHICS AND DISSEMINATION

Ethical approval was obtained from The Royal Children's Hospital Human Research Ethics Committee (HREC/50874/RCHM-2019) under the National Mutual Acceptance initiative. Research governance approvals were obtained from five clinical sites. Results will be disseminated through published manuscripts, conference presentations, public seminars and practical resources for stakeholder groups.

TRIAL REGISTRATION NUMBER

ACTRN12620000416998; Australian and New Zealand Clinical Trial Registry.

Prader-Willi Syndrome in children: Quality of life and caregiver burden

Prader-Willi syndrome is a complex condition requiring constant care and supervision of the affected child.

AIM

To evaluate quality of life and caregiver burden in children with Prader-Willi syndrome.

METHODS

All children with Prader-Willi syndrome, attending a tertiary referral centre, were invited to participate (n = 44). Quality of life was evaluated using the PedsQL questionnaire. Family impact modules and parent proxy reports evaluated the impact on the quality of life of the child and family. Additional challenges were captured using a burden questionnaire.

RESULTS

Nineteen children participated. Median age was 7.9 years (0.6-18.1 years). Majority were female (n = 14, 74%). Median age at diagnosis was 2.5 weeks (range birth-2 years 8 months). Growth hormone treatment was in place for the majority (n = 14, 74%). Increased weight and age were identified as significantly impacting on family functioning and relationships. Parents perceived increased weight and age to have a significant negative impact on their child's psychosocial health and social functioning. Caregivers of children >12 years reported an increased burden of care. Disruption to routines, restriction of social activities and psychological difficulties were reported as increasing caregiver burden.

CONCLUSION

Prader-Willi syndrome impacts significantly on quality of life for both the affected child and the family.

Recognizing the unique prenatal phenotype of Prader-Willi Syndrome (PWS) indicates the need for a diagnostic methylation test

OBJECTIVES

Prader-Willi syndrome (PWS) is a neurogenetic disorder characterized by mental retardation, morbid obesity, and endocrine and behavior disorders. We previously showed in a small group of patients that PWS may have a unique prenatal phenotype. We aimed to characterize clinical and ultrasonic features in a larger series of pregnancies with a PWS fetus.

METHODS

We retrospectively interviewed all mothers of children with PWS followed in the Israel national multidisciplinary PWS clinic. We compared details of the PWS pregnancy with the pregnancies of healthy siblings and with data from the general population. Medical records including ultrasound reports, obstetric records, and genetic results were analyzed.

RESULTS

Distinct prenatal features of PWS pregnancies included abnormal fetal growth [fetal growth restriction (FGR) (37.3%), increased head to abdominal circumference ratio (44.8%), decreased abdominal circumference (49.2%)], markedly decreased fetal movements (DFM) (80.4%), and polyhydramnios (42.0%) (P < 0.001 for all). The combination of abnormal growth accompanied by polyhydramnios or DFM was highly suggestive for PWS.

CONCLUSIONS

Recognition of the unique PWS phenotype should alert obstetricians to consider the possibility of PWS, perform the diagnostic methylation test, provide appropriate counseling, and plan optimal management of the affected pregnancy.

Requirements for improving health and well-being of children with Prader-Willi syndrome and their families

Prader-Willi syndrome (PWS) is a rare genetic condition with multi-system involvement. The literature was reviewed to describe neurodevelopment and the behavioural phenotype, endocrine and metabolic disorders and respiratory and sleep functioning. Implications for child and family quality of life were explored. Challenging behaviours contribute to poorer well-being and quality of life for both the child and caregiver. Recent evidence indicates healthy outcomes of weight and height can be achieved with growth hormone therapy and dietary restriction and should be the current target for all individuals with PWS. Gaps in the literature included therapies to manage challenging behaviours, as well as understanding the effects of growth hormone on respiratory and sleep function. New knowledge regarding the transition of children and families from schooling and paediatric health services to employment, accommodation and adult health services is also needed. Developing a national population-based registry could address these knowledge gaps and inform advocacy for support services that improve the well-being of individuals with PWS and their families.

Physiotherapists perceived developing positive rapport facilitates participation in exercise among people with Prader-Willi Syndrome: a qualitative study

Purpose: To explore the experiences of physiotherapists delivering community-based progressive resistance training for people with Prader-Willi syndrome (PWS).Method: Participants in this qualitative study were fifteen physiotherapists (13 female) who had supervised 14 young adults with PWS to complete a progressive resistance training program, twice per week for 10 weeks. Semi-structured interviews with the physiotherapists were audio-recorded and transcribed verbatim. Interview transcripts were checked for accuracy by the physiotherapists. Data were analysed using thematic analysis with an inductive approach and data were managed using NVivo software.Results: Development of positive rapport between physiotherapists and people with PWS emerged as the critical factor. Components of developing positive rapport with a person with PWS included clear communication, adaptability in approach, fostering independence in the person with PWS, and motivating the person by developing confidence. Creating a routine, empowering the people with PWS to take ownership of their progress and developing confidence made continued participation in exercise by the people with PWS more likely.Conclusions: Our findings highlight the importance of developing rapport with people with PWS to facilitate their participation in exercise. Physiotherapist attributes and skills such as adaptability and communication positively influence participation in community-based exercise for people with PWS. Implications for rehabilitationThe critical factor for maximising the participation of people with PWS in high-intensity exercise is the development of positive rapport by the physiotherapistDevelopment of positive rapport was facilitated by therapist adaptability and clear communication.People with PWS might be motivated to exercise by developing their confidence and fostering their independence.

The Italian National Rare Diseases Registry: a model of comparison and integration with Hospital Discharge Data

BACKGROUND

Italy has been the first country at European level to implement a population-based public health registry dedicated to rare diseases. This study describes the current situation of the Italian National Rare Diseases Registry (NRDR) and compares its data with those from the National Hospital Discharge Database (HDD).

METHODS

Three rare diseases were analysed: Huntington disease (HD), Hereditary Haemorragic Telangiectasia (HHT) and Prader-Willi Syndrome (PWS), selected for their different characteristics. The two sources (NRDR and HDD) were linked: incidence rate ratio (IRR), sensitivity and predictive positive value (PPV) were calculated.

RESULTS

Incidence rates from NRDR and from HDD were compared by age groups, and IRR calculated: 1.08 for HD, 1.41 for HHT, 1.21 for PSW. For HD, sensitivity was 0.52 and PPV 0.48; for HHT sensitivity was 0.71 and PPV 0.52; for PWS the sensitivity was 0.71 and PPV 0.58. We found a strong regional variability in the results.

CONCLUSIONS

The integrated use of the two sources helps tracking those cases that are not captured by the Registry; further, it is a precious tool to accurately describe clinical histories of rare disease affected individuals, in terms of concomitant pathologies and medical procedures performed during hospitalization.

Motor performance in Prader-Willi syndrome patients and its potential influence on caregiver's quality of life

Background

Prader-Willi syndrome (PWS) is a complex, multisystem genetic disorder characterized by a variety of physical, cognitive, and behavioral impairments. PWS is a unique sarcopenia model characterized by an abnormal increase in body fat mass and a decrease in muscle mass that predisposes patients to reduced physical activity, functional limitations, and disability. These manifestations may require both symptomatic and supportive management, thus negatively influencing their lifelong family caregiver’s quality of life. The aim of this study was to examine the functional motor performance of adults with PWS in Taiwan and to measure the quality of life of their primary family caregivers.

Methods

The functional motor tests consisted of the following: (1) 30-s sit-to-stand test, (2) timed up-and-go test, (3) hand grip and lateral pinch strength tests, and (4) Berg Balance Scale. The World Health Organization Quality of Life-short form (WHOQOL-BREF) and the Short-Form 36 Health Survey Questionnaire (SF-36) were used to evaluate health-related quality of life, and the parenting stress index was used to assess the magnitude of stress within the parent-child system.

Results

The participants included seven adults (two females and five males) with genetically confirmed PWS and their respective main caregivers. The mean age of the adults with PWS was 25.28 years; range 18–31 years, SD 5.10; the mean BMI was 29.2 kg/m², SD 6.43. All adults with PWS showed lower hand grip and lateral pinch strengths, fewer sit-to-stand cycles during the 30-s chair stand test, and greater average time during the timed up-and-go test when compared to the normative data on healthy adults. Balance was negatively correlated with the caregiver’s health concepts of social functioning (r_s −0.879, P = 0.009) and with role limitations due to physical problems (r_s −0.899, P = 0.006) and emotional problems (r_s −0.794, P = 0.033); hand grip strength was negatively correlated with bodily pain (r_s −0.800, P = 0.031), as assessed using the SF-36 questionnaire. The timed up-and-go test was positively correlated with the social relationship domain (r_s 0.831, P = 0.021), as assessed using the WHOQOL-BREF questionnaire. The parenting stress index showed no association with the PWS patient’s physical activities.

Conclusions

All adults with PWS showed decreased upper and lower limb strength and functional mobility when compared to healthy adults. Some of their motor performance might have negative effects on their primary family members in terms of social participation and physical and emotional role limitations. Future research should explore the relationship between physical performances, psychological difficulties of PWS and caregiver’s QOL.

Quality of life in children with Prader Willi Syndrome: Parent and child reports

PURPOSE

The purpose of this study was to evaluate the use of the Peds QL4.0 instrument to assess quality of life (QL) in children with Prader Willi Syndrome (PWS). This study also sought to compare differences in parent and child report as well as between children with PWS and without PWS.

METHODS

Parents and children with PWS (N=44) completed the PedsQL 4.0 instrument. A sub-sample of children completed the Peds QL 4.0 a second time to assess test-retest reliability. A comparison sample of children who were obese but without PWS (N=66) also completed the PedsQL 4.0.

RESULTS

PedsQL 4.0 showed acceptable internal consistency for the child report (αs >0.72) and was acceptable for 4 out of the 6 scales for the parent report (αs >0.66). Test-retest reliability coefficients showed support for the reliability of the instrument (ICCs>0.64). Parents perceived lower QL than children with PWS. Children with PWS also showed lower QL than children without PWS.

CONCLUSIONS

This study provides support for the use of the PedsQL 4.0 instrument in children with PWS. As observed in other populations, parents perceive a lower QL for their children with PWS than the children themselves.

Beneficial Effect of Growth Hormone Treatment on Health-Related Quality of Life in Children with Prader-Willi Syndrome: A Randomized Controlled Trial and Longitudinal Study

BACKGROUND/AIMS

Growth hormone (GH) treatment is beneficial for children with Prader-Willi syndrome (PWS), but data about health-related quality of life (HRQOL) and effects of GH treatment are scarce. We, therefore, investigated the effects of GH treatment on HRQOL in PWS children.

METHODS

In a randomized controlled GH trial including 26 PWS children and during an 11-year longitudinal GH study in 76 children, we annually assessed HRQOL recorded by patients and parents, using a generic questionnaire (DUX25), containing 4 subdomains (Physical, Home, Social, and Emotional) and a PWS-specific questionnaire (DUXPW).

RESULTS

At baseline, PWS children rated HRQOL similar to or higher than healthy and obese children. GH-treated children reported an increase in HRQOL in the Physical and Social subdomains and the DUXPW compared to untreated children. Parents reported an increase in the Physical and Emotional subdomains and borderline in the total DUX25 compared to parents of untreated children. During the 11 years of GH treatment, the Physical subdomain continued to improve, according to parents, whereas the Home, Social and Emotional subdomains, the total DUX25, and the DUXPW remained similar, according to children and parents.

CONCLUSIONS

PWS children rated HRQOL equally to or better than healthy and obese children. HRQOL increased during GH treatment, in contrast to HRQOL of untreated children. This effect was sustained during long-term GH treatment. PWS children consider themselves quite happy, despite some difficulties related to the syndrome.

Feeding, eating and behavioral disturbances in Prader-Willi syndrome and non-syndromal obesity

BACKGROUND

Although most individuals with Prader-Willi syndrome (PWS) are obese, little is known about the impact of obesity-related psychosocial factors in PWS. In the present study we compared feeding, eating, and behavioral disturbances in children and adolescents with PWS, peers with non-syndromal obesity, and normal weight controls.

METHODS

Twelve persons with PWS, aged 7-22 years, age- and gender-matched obese and normal weight individuals were analyzed regarding parental feeding practices, eating disturbances, and behavioral problems via standardized questionnaires.

RESULTS

Parents of individuals with PWS reported significantly more restrictive feeding and monitoring than did parents of obese or normal weight children without PWS (p<0.05). Social problems were more common in the obese and the PWS group than in the normal-weight group (p<0.05). Behavioral problems were significantly correlated with parental restrictive feeding practices.

CONCLUSIONS

Our data show that children and adolescents with PWS are affected by psychosocial problems, and that restrictive feeding practices might be associated with more severe behavioral problems. Further studies in larger samples will be necessary to replicate these results and possibly provide new therapeutic approaches for the management of PWS.

Quality of life in adolescents and adults with CHARGE syndrome

Health-related Quality of Life and the Impact of Childhood Neurologic Disability Scale were collected for 53 patients with CHARGE syndrome aged 13-39 years with a mean academic level of 4th grade. The most prevalent new and ongoing issues included bone health issues, sleep apnea, retinal detachment, anxiety, and aggression. Sleep issues were significantly correlated with anxiety, self-abuse, conduct problems, and autistic-like behaviors. Problems with overall health, behavior, and balance most affected the number of social activities in the individual's life. Sensory impairment most affected relationships with friends. Two contrasting case studies are presented and demonstrate that the quality of life exists on a broad spectrum in CHARGE syndrome, just as its physical features range from mild to very severe. A multitude of factors, including those beyond the physical manifestations, such as anxiety and sleep problems, influence quality of life and are important areas for intervention. © 2016 Wiley Periodicals, Inc.

Social/economic costs and health-related quality of life in patients with Prader-Willi syndrome in Europe

OBJECTIVE

The aim of this study was to determine the economic burden from a societal perspective and health-related quality of life (HRQOL) of patients with Prader-Willi syndrome (PWS) in Europe.

METHODS

We conducted a cross-sectional study of patients with PWS from Spain, Bulgaria, Hungary, Germany, Italy, the UK, Sweden and France. Data on demographic characteristics, healthcare resource utilisation, informal care, labour productivity losses and HRQOL were collected from questionnaires completed by patients or their caregivers. HRQOL was measured with the EuroQol 5-domain (EQ-5D) questionnaire.

RESULTS

A total of 261 patients completed the questionnaire. The average annual costs ranged from € 3937 to € 67,484 between countries; the reference year for unit prices was 2012. Direct healthcare costs ranged from € 311 to € 18,760, direct non-healthcare costs ranged from € 1269 to € 44,035, and loss of labour productivity ranged from € 0 to € 2255. Costs were also shown to differ between children and adults. The mean EQ-5D index score for adult PWS patients ranged between 0.40 and 0.81 and the mean EQ-5D visual analogue scale score ranged between 51.25 and 90.00.

CONCLUSION

The main strengths of this study lie in our bottom-up approach to costing and in the evaluation of PWS patients from a broad societal perspective. This type of analysis is very scarce in the international literature on rare diseases in comparison with other illnesses. We conclude that PWS patients incur considerable societal costs and experience substantial deterioration in HRQOL.

Review of growth hormone therapy in adolescents and young adults with Prader-Willi syndrome

Consensus guidelines from the Growth Hormone Research Society Workshop recommend growth hormone therapy in all children with genetically confirmed Prader-Willi syndrome (PWS) in combination with dietary, lifestyle and environmental interventions. As yet, however, there are limited published data regarding the use of growth hormone therapy in adolescents and young adults with PWS. This review focuses on the advantages and disadvantages of growth hormone therapy in this particular group. The risk of complications, challenges with consent for therapy, the need for contraception in females with PWS and the appropriate monitoring required are all factors which must be carefully considered in this challenging patient group. Transition from paediatric to adult services can be difficult for most adolescents, but especially so for PWS adolescents and should be undertaken under the care of experienced paediatric and adult endocrinologists and a multidisciplinary team approach. Further research is, however, still required in the management of PWS patients during adolescence.

Prader-Willi syndrome can be diagnosed prenatally

The aim of this study was to characterize the fetal phenotype of a cohort of individuals with confirmed diagnoses of Prader-Willi syndrome (PWS), a severe multi-system genetic disorder, diagnosed by a specific methylation test. We interviewed mothers of 106 individuals with PWS to obtain information about the pregnancy of their affected child. For 47 pregnancies of children younger than 10 years, we also reviewed the obstetric ultrasound and detailed obstetric history from medical records. We compared the PWS pregnancies with those of the sibling closest in age and with the general population. McNemars, Chi-square and Fisher exact tests were used for statistical analyses. Decreased fetal movements, small for gestational age (SGA), asymmetrical intrauterine growth (increased head/abdomen circumferences ratio) and polyhydramnios were found in 88%, 65%, 43%, and 34%, respectively (P < 0.001 vs. siblings and P < 0.0001 vs. the general population for all measurements). No severe morphological abnormalities were found. A combination of 2, 3, and 4 abnormalities was found in 27%, 29%, and 24% of pregnancies, respectively. Fourteen out of 15 umbilical artery Doppler studies were within the normal range (93%). The rare combination of asymmetrical intrauterine growth and polyhydramnios was found in 34% of PWS pregnancies (P < 0.0001 vs. the general population). Prenatal genetic screening for PWS by methylation testing is indicated when any combination of polyhydramnios, SGA or asymmetric intrauterine growth, with normal Doppler studies is present, particularly when asymmetrical intrauterine growth and polyhydramnios coexist.

The relationship between IGF-I concentration, cognitive function and quality of life in adults with Prader-Willi syndrome

Mental retardation is one of the clinical characteristics of Prader-Willi syndrome (PWS) and in part of the patients growth hormone deficiency is demonstrable. Cognitive function seems to be influenced by insulin-like growth factor I (IGF-I); however, little is known about cognitive function in relation to IGF-I levels in PWS adults. The aim of the present study was to evaluate cognitive function in adult PWS patients in comparison to healthy siblings and to investigate whether there is a correlation between cognitive function and IGF-I levels. Anthropometric measurements, IGF-I levels, quality of life (QoL), Appetite Assessment Score, IQ (GIT and Raven) and cognitive function (by four subtests of the Cambridge Neuropsychological Automated Testing Battery, CANTAB) were evaluated in PWS patients and their healthy siblings served as control group. PWS patients had significantly lower IGF-I levels, IQ and QoL when compared to controls. Reaction times were longer and performance was worse on CANTAB subtests in PWS adults. IGF-I on one hand and IQ, Appetite Assessment Score and cognitive performance on the other hand seem to be correlated in PWS patients. In conclusion, IGF-I levels, IQ and QoL are significantly lower in PWS subjects when compared to healthy siblings. In PWS adults, temporal as well as prefrontal cognitive functions are impaired. Higher IGF-I levels appear to be related to better intellectual skills and faster temporal memory processing in PWS patients.

Body image and sexual interests in adolescents and young adults with Prader-Willi syndrome

BACKGROUND

Hypogonadism is a major feature of Prader-Willi syndrome (PWS), but clinical manifestations are variable. Sexual interests and behavior in this population have not been previously described.

OBJECTIVES

We studied PWS adolescents and young adults to assess 1) satisfaction with physical and sexual development, 2) frequency of romantic and sexual experiences, 3) aspirations and expectations regarding marriage, 4) possible relationships between sexual interests and hormone levels, and 5) the desire for hormonal replacement therapy.

METHODS

The study population consisted of 27 individuals (13 males) ages 17-32 (mean 23.5) years with genetically confirmed PWS. Mean intelligence quotient (IQ) was 75 (range 50-100). We conducted structured interviews using questionnaires specifically designed for this study.

RESULTS

There was a significant negative correlation between IQ and body image in both males and females. IQ showed a positive correlation with interest in dating and romantic activities. Approximately half of PWS males and females reported having been on a date and kissing romantically. All males and 64% of the females wished to be married. Seventy-seven per cent of PWS males wanted hormonal treatment to increase phallic size. We found no correlation between hormone levels and sexual interests. Only 43% of PWS females wanted hormonal medication to achieve regular menstruation.

CONCLUSION

Despite documented hypogonadism, PWS young adults are interested in sexual and romantic issues. The range of sexual activities and expectations is variable. Understanding specific sexual characteristics of each individual is important in order to offer proper anticipatory sexual guidance counseling and for appropriate recommendations for hormone replacement.

Long-term effects of growth hormone therapy on patients with Prader-Willi syndrome

AIM

To assess the effects of recombinant human growth hormone (rhGH) treatment in children with Prader-Willi syndrome.

DESIGN

A 1-year study and an observational follow-up visit 10 years later.

METHODS

In 20 patients with Prader-Willi syndrome (PWS): clinical assessment, laboratory tests, body composition analysis by dual energy X-ray absorptiometry, sleep polygraphy, health-related quality of life assessed by 16D.

RESULTS

Only two patients had normal growth hormone secretion at baseline. All patients were significantly shorter than their expected heights, but experienced catch-up growth during growth hormone treatment. At follow-up, 13 patients had reached adult heights and were markedly taller than historical controls. The cumulative dose of rhGH over 10 years correlated inversely with the total body fat percentage (p = 0.033). However, patients remained severely obese at 10 years. Sleep polygraphy was abnormal in more than half of the patients. Health-related quality of life of the patients remained substantially below that of normal population.

CONCLUSION

Growth hormone markedly improved adult height in subjects with PWS when compared to historical data. The cumulative dose of growth hormone correlated with reduction in body fat; nevertheless, patients remained severely obese.

Quality of life in rare genetic conditions: a systematic review of the literature

Quality of life (QoL) refers to an individual's sense of overall well-being encompassing physical, psychological, emotional, social, and spiritual dimensions. Although genetics healthcare providers strive to promote patient well-being, and the term QoL is often invoked to refer to this outcome, there is lack of clarity as to what actually constitutes QoL from the patient's perspective. This systematic literature review aims to summarize and integrate research findings to help elucidate how healthcare providers can more effectively enhance the QoL of patients affected with rare genetic conditions. Eligible studies were those that measured QoL as a primary outcome variable using a validated, multi-dimensional scale. Detailed criteria were used to rate quality of design, methodology, and analytic rigor. Fifty-eight studies were selected for inclusion in the review, and a narrative synthesis of the data was performed. A central theme emerging from the literature is that, although genetic conditions have the potential to have significant negative consequences for individuals' lives, having a genetic condition does not necessarily entail poor QoL. Evidence demonstrates that factors beyond the physical manifestations of the disease, such as psychological well-being, coping, and illness perceptions, influence QoL and may serve as potent targets for intervention. The field of research on QoL in rare genetic conditions will be advanced by uniting around a clear conceptualization of QoL and using more rigorous methodology with comprehensive measures of global QoL.