Scientific imperatives, clinical implications, and theoretical underpinnings for the investigation of the relationship between genetic variables and patient-reported quality-of-life outcomes

Estimating bidirectional effects between social connectedness and mental health in adolescent students: Addressing biases due to endogeneity

Research on the bidirectional relationship between social connectedness and health/mental health in adolescents is scarce, with most studies on adults. Some of the existing studies exploited the availability of longitudinal data to provide evidence of the existence of a causal relationship, either from social connectedness to health or establish a bidirectional relationship. There are at least two weaknesses associated with earlier research to assess the size of the effects. As acknowledged in the literature, one relates to attributing causality to empirical findings, due to well-known but inadequately addressed endogeneity biases. The other relates to failure to account for potentially important covariates, sometimes due to data limitations, or because such variables are not frequently used in sociological research. Existing research predominantly finds that the strongest path is from social connectedness to health/mental health, with effect estimates modest in size. I followed a quasi-experimental strategy by modelling adolescent students' perceptions of social connectedness and mental health perceptions as potentially endogenous variables when estimating bidirectional effects. An instrumental variables (IV) modelling approach was followed, supplemented with a recently developed alternative approach to testing the exclusion restrictions of individual instruments. I exploited the rich information available in the PISA 2018 multi-country dataset, which allows for conditioning for a wide array of information on adolescent students' personal circumstances, self-reported personality-related attributes, relationships with parents; and school characteristics. I found that (1) accounting for endogeneity biases is important; and (2) as opposed to findings reported in the literature, the dominant effect is from mental health perceptions to social connectedness for both male and female participants. The policy relevance of the findings is that adolescent mental health should be the primary focus of interventions, i.e., identifying and treating mental health symptoms as a primary intervention and as a precursor to improving the social connectedness of adolescents.

Association of MTR and MTRR genes and oral health-related quality of life in children with dental caries

This study aimed to assess whether genetic polymorphisms in MTR and MTRR are potential biomarkers of oral health-related quality of life (OHRQoL) in children with caries. A cross-sectional study was designed wherein pairs of parents/caregivers and children (aged two-five years) were selected. Clinical examination was used to detect dental caries, which were classified as low-severity and high-severity caries. The Early Childhood Oral Health Impact Scale (ECOHIS) questionnaire was used to assess OHRQoL. Genomic DNA extracted from the saliva was used to analyze two missense genetic polymorphisms: MTR (rs1805087) and MTRR (rs1801394). Mann-Whitney non-parametric test was used to analyze candidate genes with OHRQoL scale and domain, with a significance level of p≤0.05. MTR (rs1805087) was found associated (p = 0.05) with children's OHRQoL subscale scores in the dominant model (GG + AG). Genetic polymorphisms in MTR may increase the risk of poor OHRQoL in children with caries. Further studies are needed to investigate genetics, molecular factors, and OHRQoL.

Determinants and mediating mechanisms of quality of life and disease-specific symptoms among thyroid cancer patients: the design of the WaTCh study

BACKGROUND

Thyroid cancer (TC) patients are understudied but appear to be at risk for poor physical and psychosocial outcomes. Knowledge of the course and determinants of these deteriorated outcomes is lacking. Furthermore, little is known about mediating biological mechanisms.

OBJECTIVES

The WaTCh-study aims to; 1. Examine the course of physical and psychosocial outcomes. 2. Examine the association of demographic, environmental, clinical, physiological, and personality characteristics to those outcomes. In other words, who is at risk? 3. Reveal the association of mediating biological mechanisms (inflammation, kynurenine pathway) with poor physical and psychological outcomes. In other words, why is a person at risk?

DESIGN AND METHODS

Newly diagnosed TC patients from 13 Dutch hospitals will be invited. Data collection will take place before treatment, and at 6, 12 and 24 months after diagnosis. Sociodemographic and clinical information is available from the Netherlands Cancer Registry. Patients fill-out validated questionnaires at each time-point to assess quality of life, TC-specific symptoms, physical activity, anxiety, depression, health care use, and employment. Patients are asked to donate blood three times to assess inflammation and kynurenine pathway. Optionally, at each occasion, patients can use a weighing scale with bioelectrical impedance analysis (BIA) system to assess body composition; can register food intake using an online food diary; and can wear an activity tracker to assess physical activity and sleep duration/quality. Representative Dutch normative data on the studied physical and psychosocial outcomes is already available.

IMPACT

WaTCh will reveal the course of physical and psychosocial outcomes among TC patients over time and answers the question who is at risk for poor outcomes, and why. This knowledge can be used to provide personalized information, to improve screening, to develop and provide tailored treatment strategies and supportive care, to optimize outcomes, and ultimately increase the number of TC survivors that live in good health.

Measuring Clinical, Biological, and Behavioral Variables to Elucidate Trajectories of Patient (Reported) Outcomes: The PROFILES Registry

To take cancer survivorship research to the next level, it's important to gain insight in trajectories of changing patient (reported) outcomes and impaired recovery after cancer. This is needed as the number of survivors is increasing and a large proportion is confronted with changing health after treatment. Mechanistic research can facilitate the development of personalized risk-stratified follow-up care and tailored interventions to promote healthy cancer survivorship. We describe how these trajectories can be studied by taking the recently extended Dutch population-based PROFILES (Patient Reported Outcomes Following Initial treatment and Long term Evaluation of Survivorship) registry as an example. PROFILES combines longitudinal assessment of patient-reported outcomes with novel, ambulatory and objective measures (e.g., activity trackers; blood draws; hair samples; online food diaries; online cognitive tests; weighing scales; online symptoms assessment), and cancer registry and pharmacy databases. Furthermore, we discuss methods to optimize the use of a multidomain data collection like return of individual results to participants which may not only improve patient empowerment but also long-term cohort retention. Also, advanced statistical methods are needed to handle high-dimensional longitudinal data (with missing values) and provide insight into trajectories of changing patient (reported) outcomes after cancer. Our coded data can be used by academic researchers around the world. Registries like PROFILES, that go beyond boundaries of disciplines and institutions, will contribute to better predictions of who will experience changes and why. This is needed to prevent and mitigate long-term and late effects of cancer (treatment) and to identify new interventions to promote health.

Current and Future Applications of Artificial Intelligence in Coronary Artery Disease

Cardiovascular diseases (CVDs) carry significant morbidity and mortality and are associated with substantial economic burden on healthcare systems around the world. Coronary artery disease, as one disease entity under the CVDs umbrella, had a prevalence of 7.2% among adults in the United States and incurred a financial burden of 360 billion US dollars in the years 2016–2017. The introduction of artificial intelligence (AI) and machine learning over the last two decades has unlocked new dimensions in the field of cardiovascular medicine. From automatic interpretations of heart rhythm disorders via smartwatches, to assisting in complex decision-making, AI has quickly expanded its realms in medicine and has demonstrated itself as a promising tool in helping clinicians guide treatment decisions. Understanding complex genetic interactions and developing clinical risk prediction models, advanced cardiac imaging, and improving mortality outcomes are just a few areas where AI has been applied in the domain of coronary artery disease. Through this review, we sought to summarize the advances in AI relating to coronary artery disease, current limitations, and future perspectives.

Comprehensive Assessment of Incidence, Risk Factors, and Mechanisms of Impaired Medical and Psychosocial Health Outcomes among Adolescents and Young Adults with Cancer: Protocol of the Prospective Observational COMPRAYA Cohort Study

Adolescent and young adult (AYA) cancer patients suffer from delay in diagnosis, and lack of centralized cancer care, age-adjusted expertise, and follow-up care. This group presents with a unique spectrum of cancers, distinct tumor biology, cancer risk factors, developmental challenges, and treatment regimens that differ from children and older adults. It is imperative for advances in the field of AYA oncology to pool data sources across institutions and create large cohorts to address the many pressing questions that remain unanswered in this vulnerable population. We will create a nationwide infrastructure (COMPRAYA) for research into the incidence, predictive/prognostic markers, and underlying mechanisms of medical and psychosocial outcomes for AYA between 18-39 years diagnosed with cancer. A prospective, observational cohort of (n = 4000), will be established. Patients will be asked to (1) complete patient-reported outcome measures; (2) donate a blood, hair, and stool samples (to obtain biochemical, hormonal, and inflammation parameters, and germline DNA); (3) give consent for use of routinely archived tumor tissue and clinical data extraction from medical records and registries; (4) have a clinic visit to assess vital parameters. Systematic and comprehensive collection of patient and tumor characteristics of AYA will support the development of evidence-based AYA care programs and guidelines.

Genetic Variations and Health-Related Quality of Life (HRQOL): A Genome-Wide Study Approach

Simple Summary

Health-related quality of life (HRQOL) is associated with cancer prognosis as well as with age, sex, race, and lifestyle factors, including diet and physical activity. To investigate the hypothesis that HRQOL has genetic underpinnings in patients with cancer, we performed a genome-wide association study to evaluate genetic variants (single nucleotide polymorphisms, SNPs) associated with mental and physical QOL as measured by the PROMIS assessment tool in breast cancer survivors participating in a longitudinal cohort study, the Mayo Clinic Breast Disease Registry (MCBDR). Age and financial concerns were associated with worse physical and mental health, and previous receipt of chemotherapy was associated with worse mental health. SNPs in SCN10A, LMX1B, SGCD, PARP12, and SEMA5A were associated with physical and mental QOL, but none at the genome-wide significance thresholds of p < 5 × 10⁻⁸.

Abstract

Health-related quality of life (HRQOL) is an important prognostic patient-reported outcome in oncology. Because prior studies suggest that HRQOL is, in part, heritable, we performed a GWAS to elucidate genetic factors associated with HRQOL in breast cancer survivors. Physical and mental HRQOL were measured via paper surveys that included the PROMIS-10 physical and mental health domain scales in 1442 breast cancer survivors participating in the Mayo Clinic Breast Disease Registry (MCBDR). In multivariable regression analyses, age and financial concerns were significantly associated with global physical health (age: p = 1.6 × 10⁻²³; financial concerns: p = 4.8 × 10⁻⁴⁰) and mental health (age: p = 3.5 × 10⁻⁷; financial concerns: p = 2.0 × 10⁻⁶⁹⁾. Chemotherapy was associated with worse global mental health (p = 0.01). In the GWAS, none of the SNPs reached the genome-wide association significance threshold of 5 × 10⁻⁸ for associations with either global physical or global mental health, however, a cluster of SNPs in SCN10A, particularly rs112718371, appeared to be linked to worse global physical health (p = 5.21 × 10⁻⁸). Additionally, SNPs in LMX1B, SGCD, PARP12 and SEMA5A were also moderately associated with worse physical and mental health (p < 10⁻⁶). These biologically plausible candidate SNPs warrant further study as possible predictors of HRQOL.

Genetic polymorphisms and haplotypes of BRCA1 gene associated with quality of life and survival among patients with non-small-cell lung cancer

PURPOSE

Quality of life (QoL) and prognosis of lung cancer (LC) patients are poor. Previous studies focused less on the relationship between genetic factors and the QoL of LC patients. The current study is intended to explore the association of SNPs and haplotypes of BRCA1 and the QoL and survival of patients with LC.

METHODS

QOL of 291 non-small-cell LC patients was measured by EORTC Core Quality of Life Questionnaire (QLQ-C30) and EORTC Quality of Life Questionnaire-Lung Cancer 13 (QLQ-LC13) before discharge. Three tag SNPs of the BRCA1 gene (rs1799966, rs3737559, rs8067269) were detected using an improved multiplex ligation detection reaction (iMLDR) technique. Haplotype analysis was conducted using the software Haploview 4.2. The patients' survival was followed up every six months until March 2019.

RESULTS

rs8067269 was associated with physical functioning (β = 7.97, p = 0.024) and diarrhea (Odds ratios (OR) 0.32, p = 0.042). rs1799966-rs3737559-rs8067269 haplotype was associated with several domains of QoL, including physical functioning (TCG vs. CCA: β = 6.21, p = 0.010), worse dyspnea (TCG vs. CTA: OR 2.05, p = 0.031) and peripheral neuropathy (TCG vs. CTA: OR 3.91, p = 0.030). BRCA1 rs1799966 CC genotype, rs8067269 AA genotype and CCA haplotype were associated with longer survival time of LC patients (p < 0.05).

CONCLUSION

SNPs and haplotypes of BRCA1 gene were associated with the QoL and survival of patients with LC. Patients with certain genotypes and haplotypes (i.e., rs8067269 AA genotype, or CCA haplotype) had better QoL and prognosis.

Cytokine Genetic Variants and Health-Related Quality of Life in Crohn's Disease: An Exploratory Study

BACKGROUND

Crohn's disease (CD) is an inflammatory condition that has deleterious effects on patients' health-related quality of life (HRQoL). Demographic, clinical, and psychosocial factors contribute to variability in HRQoL; however, the influence of genetic variations related to altered inflammatory responses in individuals with CD is unknown. This exploratory study compared HRQoL scores across genotypes of functional genetic polymorphisms in cytokine candidate genes among individuals with CD.

METHOD

This study used data and blood samples collected in a parent study in 39 patients with CD aged 15-30 years. Participant reports of HRQoL were collected using the Shortened Inflammatory Bowel Disease Questionnaire (SIBDQ). Genetic data were collected for 18 functional polymorphisms in eight cytokine candidate genes. SIBDQ scores were compared among genotypes using one-way, between-subjects analysis of variance.

RESULTS

SIBDQ scores differed across genotypes as follows: for IL-1R2 rs4141134 scores differed for total SIBDQ (p = .004) and systemic (p = .011), emotion (p = .038), and social domains (p = .025); for IL-10 rs1878672, scores differed for total SIBDQ (p = .031) and social domain (p = .008); for NFKB2 rs1056890, scores differed for social domain (p = .041); for TNF-α rs1800629, scores differed for total SIBDQ (p = .001) and bowel (p = .026), systemic (p = .014), and social domains (p = .045).

CONCLUSIONS

Findings on differences in SIBDQ scores across functional genetic polymorphisms in cytokine genes suggest potential mechanisms that contribute to variability in HRQoL in adolescents and young adults with CD.

The combined polymorphisms of interleukin-6-174GG genotype and interleukin-10 ATA haplotype are associated with a poor quality of life in patients with chronic hepatitis C

PURPOSE

Chronic hepatitis C (CHC) is associated with a decreased health-related quality of life (HRQOL). More recent studies have pointed toward a genetic basis of patient-reported quality of life outcomes. Taking into account that the influence of single-nucleotide polymorphisms (SNPs) on the HRQOL of CHC patients has not been studied, we investigated the combined IL10-1082G/A, - 819C/T, and - 592C/A SNPs, and IL6-174G/C SNP. We also evaluated the association between demographic, clinical, psychiatric, virological, and genetic variables with domains and summaries of HRQOL in CHC patients.

METHODS

132 consecutive CHC patients and 98 controls underwent psychiatric evaluation by using the Mini International Neuropsychiatric Interview. HRQOL was assessed by a generic questionnaire, the Medical Outcomes Study 36-Item Short Form Health Survey (SF-36), and by the specific Liver Disease Quality of Life Questionnaire (LDQOL). IL6 and IL10 polymorphisms were evaluated by Taqman SNP genotyping assay. Multivariate analysis was used to evaluate the associations.

RESULTS

Major depressive disorder was associated with lower SF-36 and LDQOL scores in seven and ten domains, respectively. Diabetes and hypertension were also associated with reduced HRQOL. CHC patients carrying the combination of IL10 ATA haplotype/IL6-GG genotype had lower scores in the SF-36-physical functioning domain, and reduced scores in the LDQOL effects of liver disease on activities of daily living, quality of social interaction, and sexual function domains than the non-carriers of the combined haplotype/genotype.

CONCLUSION

This is the first study to demonstrate that combined IL6 high-producer GG genotype and IL10 low-producer ATA haplotype is associated with poorer HRQOL in CHC patients.

Cytokine Gene Polymorphisms Associated With Various Domains of Quality of Life in Women With Breast Cancer

CONTEXT

Little is known about the phenotypic and molecular characteristics associated with various domains of quality of life (QOL) in women after breast cancer surgery.

OBJECTIVES

In a sample of women with breast cancer (n = 398), purposes were as follows: to identify latent classes with distinct trajectories of QOL from before surgery through six months after surgery and to evaluate for differences in demographic and clinical characteristics, as well as for polymorphisms in cytokine genes, between these latent classes.

METHODS

Latent class analyses were done to identify subgroups of patients with distinct QOL outcomes. Candidate gene analyses were done to identify cytokine gene polymorphisms associated with various domains of QOL (i.e., physical, psychological, spiritual, social).

RESULTS

One latent class was identified for the psychological and spiritual domains. Two latent classes were identified for the social domain and overall QOL scores. Three latent classes were identified for the physical domain. For the physical and social domains, as well as for the overall QOL scores, distinct phenotypic characteristics (i.e., younger age, poorer functional status, higher body mass index, and receipt of adjuvant chemotherapy) and a number of cytokine gene polymorphisms (CXCL8, NFKB2, TNFSF, IL1B, IL13, and NFKB1) were associated with membership in the lower QOL classes.

CONCLUSIONS

Findings suggest that women experience distinctly different physical well-being, social well-being, and total QOL outcomes during and after breast cancer surgery. The genetic associations identified suggest that cytokine dysregulation influences QOL outcomes. However, specific QOL domains may be impacted by different cytokines.

Patient-Reported Outcomes in Patients with Chronic Kidney Disease and Kidney Transplant-Part 1

Chronic kidney disease (CKD) is a complex medical condition that is associated with several comorbidities and requires comprehensive medical management. Given the chronic nature of the condition, its frequent association with psychosocial distress, and its very significant symptom burden, the subjective patient experience is key toward understanding the true impact of CKD on the patients’ life. Patient-reported outcome measures are important tools that can be used to support patient-centered care and patient engagement during the complex management of patients with CKD. The routine collection and use of patient-reported outcomes (PROs) in clinical practice may improve quality of care and outcomes, and may provide useful data to understand the disease from both an individual and a population perspective. Many tools used to measure PROs focus on assessing health-related quality of life, which is significantly impaired among patients with CKD. Health-related quality of life, in addition to being an important outcome itself, is associated with clinical outcomes such as health care use and mortality. In Part 1 of this review, we provide an overview of PROs and implications of their use in the context of CKD. In Part 2, we will review the selection of appropriate measures and the relevant domains of interest for patients with CKD.

Phenotypic and molecular characteristics associated with various domains of quality of life in oncology patients and their family caregivers

PURPOSE

Not all oncology patients and their family caregivers (FCs) experience the same quality of life (QOL). The purposes of this study were to identify latent classes of oncology patients (n = 168) and their FCs (n = 85) with distinct physical, psychological, social, and spiritual well-being trajectories from prior to through 4 months after the completion of radiation therapy and to evaluate for demographic, clinical, and genetic characteristics that distinguished between these latent classes.

METHODS

Using growth mixture modeling, two latent classes were found for three (i.e., physical, psychological, and social well-being) of the four QOL domains evaluated.

RESULTS

Across these three domains, the largest percentage of participants reported relatively high well-being scores across the 6 months of the study. Across these three QOL domains, patients and FCs who were younger, female, belonged to an ethnic minority group, had children at home, had multiple comorbid conditions, or had a lower functional status, were more likely to be classified in the lower QOL class. The social well-being domain was the only domain that had a polymorphism in nuclear factor kappa beta 2 (NFKB2) associated with latent class membership. Carrying one or two doses of the rare allele for rs7897947 was associated with a 54 % decrease in the odds of belonging to the lower social well-being class [OR (95 % CI) = .46 (.21, .99), p = .049].

CONCLUSIONS

These findings suggest that a number of phenotypic and molecular characteristics contribute to differences in QOL in oncology patients and their FCs.

In Search for the Genetic Basis of Quality of Life in Healthy Swedish Women--A GWAS Study Using the iCOGS Custom Genotyping Array

BACKGROUND

Quality of life (QoL) is increasingly measured in both research and clinical practice. QoL-assessments are built on a long, empirically-based, and stringent approach. There is ample evidence that QoL is, in part, heritable. We therefore performed a GWAS relating genetic variation to QoL in healthy females.

METHODS

In 5,142 healthy females, background characteristics (e.g. demographic, clinical, lifestyle and psychological factors) and QoL by means of the EORTC QLQ-C30 were measured. Moreover, women were genotyped using a custom array including ~210,000 single nucleotide polymorphisms (SNPs). Initially, SNPs were related to each QoL-domain, by means of partially adjusted (controlling for age and population stratification) and fully adjusted (controlling for age, population stratification, and background characteristics) regression analyses. Additionally, gene-based analyses were performed relating the combined effect of SNPs within each gene to QoL using the statistical software package VEGAS.

RESULTS

None of the associations between QoL and genetic variation (i.e. individual SNPs and genes) reached the bonferroni corrected significance level.

CONCLUSION

Reasons for a lack of association between genetic markers and QoL could be low variation in QoL-scores; selecting genetic markers not tagging QoL; or that the genetic effect that impacts one's QoL is mediated through biological pathways rather than the effect of single SNPs or genes. Therefore, we opt for a pathway-based or system biology approach as a complementary and powerful approach to analyze the combined effect of genes and their biological implications in future studies focusing on QoL-issues.

Fatigue as a Driver of Overall Quality of Life in Cancer Patients

Background

This manuscript describes an approach for analyzing large amounts of disparate clinical data to elucidate the most impactful factor(s) that relate to a meaningful clinical outcome, in this case, the quality of life of cancer patients. The relationships between clinical and quality of life variables were evaluated using the EORTC QLQ-C30 global health domain—a validated surrogate variable for overall cancer patient well-being.

Methods

A cross-sectional study design was used to evaluate the determinants of global health in cancer patients who initiated treatment at two regional medical centers between January 2001 and December 2009. Variables analyzed included 15 EORTC QLQ-C30 scales, age at diagnosis, gender, newly diagnosed/ recurrent disease status, and stage. The decision tree algorithm, perhaps unfamiliar to practicing clinicians, evaluates the relative contribution of individual parameters in classifying a clinically meaningful functional endpoint, such as the global health of a patient.

Findings

Multiple patient characteristics were identified as important contributors. Fatigue, in particular, emerged as the most prevalent indicator of cancer patients’ quality of life in 16/23 clinically relevant subsets. This analysis allowed results to be stated in a clinically-intuitive, rule set format using the language and quantities of the Quality of Life (QoL) tool itself.

Interpretation

By applying the classification algorithms to a large data set, identification of fatigue as a root factor in driving global health and overall QoL was revealed. The ability to practice mining of clinical data sets to uncover critical clinical insights that are immediately applicable to patient care practices is illustrated.

The longitudinal relationship between quality of life and survival in advanced stage cancer

OBJECTIVES

Quality of Life (QoL) at baseline is frequently found to be a prognostic factor in cancer studies. However, little is known about the relationship of the trajectory of QoL and survival in patients with advanced cancer. This study evaluates the effects of both level and change of QoL on survival to explore the potential of utilizing longitudinal information of QoL for prognosis.

METHODS

A series of joint models were used in a sample (N = 512) of patients diagnosed with advanced cancer (sample consisted of nine different cancer sites) with assessments of QoL across six time points and with survival information recorded up to 28 months after diagnosis. We used FACT-G as the QoL measure, and we evaluated the effects of change in QoL controlling for the time-dependent effects of chemotherapy and radiation.

RESULTS

The median survival for patients was 14.2 months, and 10% of the sample had survived beyond 28 months after the diagnosis of advanced cancer. The effect of change of QoL on survival was significant (hazard ratio = 0.98; p < 0.001) controlling for time-dependent treatment effects. Also, the slope of the trajectory in QoL was found to be a significant predictor of survival (hazard ratio = 0.18; p < 0.001).

CONCLUSION

These preliminary findings suggest that the patient's longitudinal experience in QoL may be a significant prognostic factor of survival, a novel finding with potentially important implications in medical decision making. Longitudinal information on QoL can be used for updating the patient's prognosis of survival.

Association between single-nucleotide polymorphisms in growth factor genes and quality of life in men with prostate cancer and the general population

PURPOSE

Improved survival for men with prostate cancer has led to increased attention to factors influencing quality of life (QOL). As protein levels of vascular endothelial growth factor (VEGF) and insulin-like growth factor 1 (IGF-1) have been reported to be associated with QOL in people with cancer, we sought to identify whether single-nucleotide polymorphisms (SNPs) of these genes were associated with QOL in men with prostate cancer.

METHODS

Multiple linear regression of two data sets (including approximately 750 men newly diagnosed with prostate cancer and 550 men from the general population) was used to investigate SNPs of VEGF and IGF-1 (10 SNPs in total) for associations with QOL (measured by the SF-36v2 health survey).

RESULTS

Men with prostate cancer who carried the minor 'T' allele for IGF-1 SNP rs35767 had higher mean Role-Physical scale scores (≥0.3 SD) compared to non-carriers (p < 0.05). While this association was not identified in men from the general population, one IGF-1 SNP rs7965399 was associated with higher mean Bodily Pain scale scores in men from the general population that was not found in men with prostate cancer. Men from the general population who carried the rare 'C' allele had higher mean Bodily Pain scale scores (≥0.3 SD) than non-carriers (p < 0.05).

CONCLUSIONS

Through identifying SNPs that are associated with QOL in men with prostate cancer and men from the general population, this study adds to the mapping of complex interrelationships that influence QOL and suggests a role for IGF-I in physical QOL outcomes. Future research may identify biomarkers associated with increased risk of poor QOL that could assist in the provision of pre-emptive support for those identified at risk.

The genetic basis of quality of life in healthy Swedish women: a candidate gene approach

BACKGROUND

Quality of life (QoL) is an increasingly important parameter in clinical practice as it predicts mortality and poor health outcomes. It is hypothesized that one may have a genetic predisposition for QoL. We therefore related 139 candidate genes, selected through a literature search, to QoL in healthy females.

METHODS

In 5,142 healthy females, background characteristics (i.e. demographic, clinical, lifestyle, and psychological factors) were assessed. QoL was measured by the EORTC QLQ-C30, which consists of 15 domains. For all women genotype information was available. For each candidate gene, single nucleotide polymorphisms (SNPs) were identified based on their functional (n = 2,663) and physical annotation (n = 10,649). SNPs were related to each QoL-domain, while controlling for background characteristics and population stratification. Finally, gene-based analyses were performed relating the combined effect of 10,649 SNPs (selected based on physical annotation) for each gene, to QoL using the statistical software package VEGAS.

RESULTS

Overall, we found no relation between genetic variations (SNPs and genes) and 14 out of 15 QoL-domains. The strongest association was found between cognitive functioning and the top SNP rs1468951 (p = 1.21E-05) in the GSTZ1 gene. Furthermore, results of the gene-based test showed that the combined effect of 11 SNPs within the GSTZ1 gene is significantly associated with cognitive functioning (p = 2.60E-05).

CONCLUSION

If validated, the involvement of GSTZ1 in cognitive functioning underscores its heritability which is likely the result of differences in the dopamine pathway, as GSTZ1 contributes to the equilibrium between dopamine and its neurotoxic metabolites via the glutathione redox cycle.

Racial/ethnic disparities in inflammatory gene single-nucleotide polymorphisms as predictors of a high risk for symptom burden in patients with multiple myeloma 1 year after diagnosis

BACKGROUND

This study was conducted to determine whether any regulatory single-nucleotide polymorphism (SNP) in an inflammatory gene was associated with a high symptom burden in patients 1 year after the diagnosis of multiple myeloma (MM).

METHODS

MM patients rated symptoms with the MD Anderson Symptom Inventory multiple myeloma module (MDASI-MM) and provided buccal-swab DNA samples. SNPs for 4 cytokine genes (interleukin 6 [IL6] -174G>C, IL1β -511C>T, tumor necrosis factor α [TNFα] -308G>A, and IL10 -1082G>A) were tested. Logistic regression models were used to identify SNPs that might predict moderate/severe symptoms (rated ≥ 4 on the MDASI-MM 0-10 scale). For the evaluation of the relationship between SNPs and overall symptom burden, a 2-step cluster analysis was used to divide patients into subgroups with high or low symptom levels.

RESULTS

Forty-one percent of the 344 patients enrolled had a high overall symptom burden. The most prevalent moderate/severe symptoms were fatigue (47%), pain (42%), numbness (38%), and bone aches (32%). For non-Hispanic whites, the IL1β -511 CC genotype was associated with a high overall symptom burden (odds ratio [OR], 2.35; 95% confidence interval [CI], 1.25-4.72; P = .004), whereas the IL6 -174 GG genotype predicted less moderate/severe fatigue (OR, 0.53; 95% CI, 0.29-0.88; P = .013). For other patients, the IL6 -174 GG genotype predicted moderate/severe pain (OR, 3.36; 95% CI, 1.23-13.64; P = .010).

CONCLUSIONS

These results support growing evidence showing that inflammation is associated with cancer-related symptoms, and they suggest that racial/ethnic factors contribute to this association.

Genetic variations underlying self-reported physical functioning: a review

PURPOSE

Genetic associations with self-reported physical functioning (SPF) are less well-studied than genetic associations with performance-measured physical functioning (PPF). We review the literature on the associations of genetic variations on SPF. We provide an overview of SPF assessment, genetic contributions to SPF including heritability, effects of genetic variations and mutations, and effects of interventions on the gene-SPF relationship. We also aim to provide directions for future research.

METHODS

A computerized literature search using PubMed, Web of Science, and PsychInfo was conducted to select relevant literature published up to November 2013. Inclusion criteria were the use of an SPF questionnaire, original articles in English on human subjects, published in peer-reviewed journals and reporting significant associations between SPF and the genome.

RESULTS

Nineteen articles were included. SPF was commonly assessed with the Short Form-36 questionnaire involving mainly convenience samples of either older persons or chronically ill. Heritability estimates were 10-30 %. Candidate genes associated with SPF could be ascribed to biological pathways associated with neurodegeneration, physiological systems regulation, or cell regulation. The APOE gene associated with neurodegeneration was most studied (n = 3). Three papers included both SPF and PPF assessments. No genome-wide association study on SPF has been conducted.

CONCLUSIONS

Associations between SPF and the genome have been investigated in selected populations in a limited number of publications. Future research should consider increasing sample variation and incorporate both SPF and PPF assessments. Also, longitudinal studies should be conducted in order to elicit stronger conclusions regarding the genetic associations with SPF.

Can quality of life assessments differentiate heterogeneous cancer patients?

Purpose

This research conducted a face validation study of patient responses to the application of an HRQOL assessment research tool in a comprehensive community cancer program setting across a heterogeneous cohort of cancer patients throughout the natural history of diagnosed malignant disease, many of whom would not be considered candidates for clinical research trial participation.

Methods

Cancer registries at two regional cancer treatment centers identified 11072 cancer patients over a period of nine years. The EORTC QLQ-C30 was administered to patients at the time of their initial clinical presentation to these centers. To determine the significance of differences between patient subgroups, two analytic criteria were used. The Mann-Whitney test was used to determine statistical significance; clinical relevance defined a range of point differences that could be perceived by patients with different health states.

Results

Univariate analyses were conducted across stratification variables for population, disease severity and demographic characteristics. The largest differences were associated with cancer diagnosis and recurrence of disease. Large differences were also found for site of origin, mortality and stage; minimal differences were observed for gender and age. Consistently sensitive QoL scales were appetite loss, fatigue and pain symptoms, and role (work-related), social and physical functions.

Conclusions

1) The EORTC QLQ-C30 collected meaningful patient health assessments in the context of non-research based clinical care, 2) patient assessment differences are manifested disparately across 15 QoL domains, and 3) in addition to indicating how a patient may feel at a point in time, QoL indicators may also reveal information about underlying biological responses to disease progression, treatments, and prospective survival.

Meta-analysis shows clinically relevant and long-lasting deterioration in health-related quality of life after esophageal cancer surgery

PURPOSE

The purpose of the study is to (1) estimate the direction, clinical relevance, and duration of health-related quality-of-life (HRQL) change in the first year following esophageal cancer surgery and (2) to assess the robustness of the estimates by subgroup and sensitivity analyses, and an exploration of publication bias.

METHODS

A systematic literature search in MEDLINE, EMBASE, CINAHL, PsychINFO, and CENTRAL to identify randomized and non-randomized studies was performed. We compared the baseline HRQL data with 3-, 6-, 9-, or 12-month follow-ups to estimate the magnitude and duration of HRQL change. These estimates were then classified as trivial, small, medium, or large. Primary outcomes were role functioning, eating, and fatigue. Secondary outcomes were physical and social functioning, dysphagia, pain, and coughing problems. We conducted subgroup analysis for open surgery, open surgery preceded by neoadjuvant therapy, and minimally invasive surgery. Sensitivity analyses assessed the influence of study design, transformation/imputation of the data, and HRQL questionnaire used.

RESULTS

We included the data from 15 studies to estimate the change in 28 HRQL outcomes after esophageal cancer surgery. The main analysis showed that patients' social functioning deteriorated. Symptoms of fatigue, pain, and coughing problems increased. These changes lasted for 9-12 months, although some symptoms persisted beyond the first year after surgery. For many other HRQL outcomes, estimates were only robust after subgroup or sensitivity analyses (e.g., role and physical functioning), or remained too heterogeneous to interpret (e.g., eating and dysphagia).

CONCLUSIONS

Patients will experience a clinically relevant and long-lasting deterioration in HRQL after esophageal cancer surgery. However, for many HRQL outcomes, more and better quality evidence is needed.

Biological pathways, candidate genes, and molecular markers associated with quality-of-life domains: an update

BACKGROUND

There is compelling evidence of a genetic foundation of patient-reported quality of life (QOL). Given the rapid development of substantial scientific advances in this area of research, the current paper updates and extends reviews published in 2010.

OBJECTIVES

The objective was to provide an updated overview of the biological pathways, candidate genes, and molecular markers involved in fatigue, pain, negative (depressed mood) and positive (well-being/happiness) emotional functioning, social functioning, and overall QOL.

METHODS

We followed a purposeful search algorithm of existing literature to capture empirical papers investigating the relationship between biological pathways and molecular markers and the identified QOL domains.

RESULTS

Multiple major pathways are involved in each QOL domain. The inflammatory pathway has the strongest evidence as a controlling mechanism underlying fatigue. Inflammation and neurotransmission are key processes involved in pain perception, and the catechol-O-methyltransferase (COMT) gene is associated with multiple sorts of pain. The neurotransmitter and neuroplasticity theories have the strongest evidence for their relationship with depression. Oxytocin-related genes and genes involved in the serotonergic and dopaminergic pathways play a role in social functioning. Inflammatory pathways, via cytokines, also play an important role in overall QOL.

CONCLUSIONS

Whereas the current findings need future experiments and replication efforts, they will provide researchers supportive background information when embarking on studies relating candidate genes and/or molecular markers to QOL domains. The ultimate goal of this area of research is to enhance patients' QOL.

Meta-analysis shows clinically relevant and long-lasting deterioration in health-related quality of life after esophageal cancer surgery

PURPOSE

The purpose of the study is to (1) estimate the direction, clinical relevance, and duration of health-related quality of life (HRQL) change in the first year following esophageal cancer surgery and (2) to assess the robustness of the estimates by subgroup and sensitivity analyses, and an exploration of publication bias.

METHODS

A systematic literature search in MEDLINE, EMBASE, CINAHL, PsychINFO, and CENTRAL to identify randomized and non-randomized studies was performed. We compared the baseline HRQL data with 3-, 6-, 9-, or 12-month follow-ups to estimate the magnitude and duration of HRQL change. These estimates were then classified as trivial, small, medium, or large. Primary outcomes were role functioning, eating, and fatigue. Secondary outcomes were physical and social functioning, dysphagia, pain, and coughing problems. We conducted subgroup analysis for open surgery, open surgery preceded by neo-adjuvant therapy, and minimally invasive surgery. Sensitivity analyses assessed the influence of study design, transformation/imputation of the data, and HRQL questionnaire used.

RESULTS

We included data from 15 studies to estimate the change in 28 HRQL outcomes after esophageal cancer surgery. The main analysis showed that patients' social functioning deteriorated. Symptoms of fatigue, pain, and coughing problems increased. These changes lasted for 9-12 months, although some symptoms persisted beyond the first year after surgery. For many other HRQL outcomes, estimates were only robust after subgroup or sensitivity analyses (e.g., role and physical functioning), or remained too heterogeneous to interpret (e.g., eating and dysphagia).

CONCLUSIONS

Patients will experience a clinically relevant and long-lasting deterioration in HRQL after esophageal cancer surgery. However, for many HRQL outcomes, more and better quality evidence is needed.

The Murcia Twin Registry: a population-based registry of adult multiples in Spain

The Murcia Twin Registry (MTR) was created in 2006, under the auspices of the University of Murcia and the regional Health Authority, aiming to develop a research resource in Spain intended to stimulate current research and new investigation on the analysis of genetic factors related to health and health-related behaviors. The MTR development strategy was designed as a step-by-step process. Initially, it was focused on women's health but nowadays it includes males and opposite-sex twins. The database comprises 2,281 participants born between 1940 and 1966 in the region of Murcia, in Spain. There have been three waves of data collection and today the MTR databases include questionnaire and anthropometric data as well as biological samples. The current main areas of research interest are health and health-related behaviors, including lifestyle, health promotion, and quality of life. Future short-term development points to the completion of the biobank and continuing the collection of longitudinal data.

Mental quality of life is related to a cytokine genetic pathway

BACKGROUND

Quality of life (QoL) in patients with chronic disease is impaired and cannot be solely explained by disease severity. We explored whether genetic variability and activity contributes to QoL in patients with Marfan syndrome (MFS), a genetic connective tissue disorder.

METHODOLOGY/PRINCIPAL FINDINGS

In 121 MFS patients, patient characteristics (i.e. demographics and MFS-related symptoms) were assessed. Patients completed the SF-36 to measure QoL. In addition, transcriptome wide gene expression and 484 Single Nucleotide Polymorphysms (SNPs) in cytokine genes were available. QoL was first analyzed and associated with patient characteristics. Patients' physical QoL was impaired and weakly related with age and scoliosis, whereas mental quality of life (MCS) was normal. To explain a largely lacking correlation between disease severity and QoL, we related genome wide gene expression to QoL. Patients with lower MCS scores had high expression levels of CXCL9 and CXCL11 cytokine-related genes (p=0.001; p=0.002); similarly, patients with low vitality scores had high expression levels of CXCL9, CXCL11 and IFNA6 cytokine-related genes (p=0.02; p=0.02; p=0.04), independent of patient characteristics. Subsequently, we associated cytokine related SNPs to mental QoL (MCS and vitality). SNP-cluster in the IL4R gene showed a weak association with MCS and vitality (strongest association p=0.0017). Although overall mental QoL was normal, >10% of patients had low scores for MCS and vitality. Post-hoc analysis of systemic inflammatory mediators showed that patients with lowest MCS and vitality scores had high levels of CCL11 cytokine (p=0.03; p=0.04).

CONCLUSIONS/SIGNIFICANCE

Variation in the cytokine genetic pathway and its activation is related to mental QoL. These findings might allow us to identify and, ultimately, treat patients susceptible to poor QoL.

Biomarkers: symptoms, survivorship, and quality of life

OBJECTIVES

To review the evidence on a number of biomarkers that show potential clinical utility in the prediction of and treatment responsiveness for the four most common symptoms associated with cancer and its treatment (ie, pain, fatigue, sleep disturbance, depression).

DATA SOURCES

Review and synthesis of review articles and data-based publications.

CONCLUSION

A growing body of evidence suggests that sensitive and specific biomarkers will be available to assist clinicians with the assessment and management of symptoms.

IMPLICATIONS FOR NURSING PRACTICE

Nurses will play a critical role in educating patients about their risk for specific symptoms based on an evaluation of specific biomarkers. Nurses will be involved in using biomarker data to titrate medications based on patient's responses to symptom management interventions.

Conceptual and Analytical Considerations toward the Use of Patient-Reported Outcomes in Personalized Medicine

BACKGROUND

Patient-reported outcomes (PROs) can play an important role in personalized medicine. PROs can be viewed as an important fundamental tool to measure the extent of disease and the effect of treatment at the individual level, because they reflect the self-reported health state of the patient directly. However, their effective integration in personalized medicine requires addressing certain conceptual and methodological challenges, including instrument development and analytical issues.

OBJECTIVES

To evaluate methodological issues, such as multiple comparisons, missing data, and modeling approaches, associated with the analysis of data related to PRO and personalized medicine to further our understanding on the role of PRO data in personalized medicine.

DISCUSSION

There is a growing recognition of the role of PROs in medical research, but their potential use in customizing healthcare is not widely appreciated. Emerging insights into the genetic basis of PROs could potentially lead to new pathways that may improve patient care. Knowledge of the biologic pathways through which the various genetic predispositions propel people toward negative or away from positive health experiences may ultimately transform healthcare. Understanding and addressing the conceptual and methodological issues in PROs and personalized medicine are expected to enhance the emerging area of personalized medicine and to improve patient care. This article addresses relevant concerns that need to be considered for effective integration of PROs in personalized medicine, with particular reference to conceptual and analytical issues that routinely arise with personalized medicine and PRO data. Some of these issues, including multiplicity problems, handling of missing values-and modeling approaches, are common to both areas. It is hoped that this article will help to stimulate further research to advance our understanding of the role of PRO data in personalized medicine.

CONCLUSION

A robust conceptual framework to incorporate PROs into personalized medicine can provide fertile opportunity to bring these two areas even closer and to enhance the way a specific treatment is attuned and delivered to address patient care and patient needs.

Characteristics of subjects with comorbidity of symptoms of generalized anxiety and major depressive disorders and the corresponding threshold and subthreshold conditions in an Arab general population sample

BACKGROUND

There is controversy about differential meaningfulness between comorbid generalized anxiety disorder (GAD)/ major depressive disorder (MDD), the corresponding "pure" disorders and subthreshold conditions. We compared subjects who met DSM-IVTR criteria of symptoms and functional impairment for comorbid GAD/MDD, versus those with GAD, MDD, subthreshold conditions, and without significant symptoms. The comparison measures were socio-demographics, clinical severity, and quality of life (QOL).

MATERIAL/METHOD

Participants (N=3155: 55.1% female, aged 16-87 yrs) were a general population sample of Kuwaitis who self-completed DSM-IVTR criteria-based questionnaires and the WHOQOL-BREF in 2006/7. We scrutinized the questionnaires and classified them into categories.

RESULTS

Of the 273 GAD and 210 MDD cases, the prevalence of comorbidity among cases with GAD was 30.8%, and 40% among MDD. Of the 398 subthreshold GAD and 194 subthreshold MDD cases, 58 had subthreshold anxiety/depression comorbidity. Comorbid threshold GAD/MDD cases were significantly older, and more likely to be women, divorced and unemployed, compared with GAD and MDD. In all measures, the threshold GAD/MDD comorbidity was the severest condition. There was a monotonic decrease in QOL with increasing anxiety-depression symptoms. For the predictors of subjective QOL, the GAD/MDD comorbidity group differed markedly from the others.

CONCLUSIONS

The high prevalence of comorbidity and subthreshold conditions supports the recommendation to assess them routinely, regardless of the primary reason for consultation. Our findings support a dimensional model with comorbid GAD/MDD at the higher end of a continuum, and differing from the "pure" conditions by a later onset and predictors of subjective wellbeing.

Genetic variations and patient-reported quality of life among patients with lung cancer

PURPOSE

Recent evidence has suggested a relationship between the baseline quality of life (QOL) self-reported by patients with cancer and genetic disposition. We report an analysis exploring relationships among baseline QOL assessments and candidate genetic variations in a large cohort of patients with lung cancer.

PATIENTS AND METHODS

QOL data were provided by 1,299 patients with non-small-cell lung cancer observed at the Mayo Clinic between 1997 and 2007. Overall QOL and subdomains were assessed by either Lung Cancer Symptom Scale or Linear Analog Self Assessment measures; scores were transformed to a scale of 0 to 10, with higher scores representing better status. Baseline QOL scores assessed within 1 year of diagnosis were dichotomized as clinically deficient (CD) or not. A total of 470 single nucleotide polymorphisms (SNPs) in 56 genes of three biologic pathways were assessed for association with QOL measures. Logistic regression with training/validation samples was used to test the association of SNPs with CD QOL.

RESULTS

Six SNPs on four genes were replicated using our split schemes. Three SNPs in the MGMT gene (adjusted analysis, rs3858300; unadjusted analysis, rs10741191 and rs3852507) from DNA repair pathway were associated with overall QOL. Two SNPs (rs2287396 [GSTZ1] and rs9524885 [ABCC4]) from glutathione metabolic pathway were associated with fatigue in unadjusted analysis. In adjusted analysis, two SNPs (rs2756109 [ABCC2] and rs9524885 [ABCC4]) from glutathione metabolic pathway were associated with pain.

CONCLUSION

We identified three SNPs in three glutathione metabolic pathway genes and three SNPs in two DNA repair pathway genes associated with QOL measures in patients with non-small-cell lung cancer.

The use of real-time patient-reported outcomes and quality-of-life data in oncology clinical practice

The collection of patient-reported outcome (PRO) data such as quality of life (QoL) has provided important information in clinical trials. Increasingly, researchers are evaluating the use of this type of data in the clinical setting. The benefits of PRO/QoL data collection, methods for collecting data and the use of the data by clinicians are increasingly being studied. This article will address the issues and benefits of QoL and other PRO data collection within oncology clinical practice.

Health-related quality of life and cancer clinical trials

The measurement of patient-reported outcomes, including health-related quality of life, is a new initiative which has emerged and grown over the past four decades. Following the development of reliable and valid self-report questionnaires, health-related quality of life has been assessed in tens of thousands of patients and a wide variety of cancers. This review is based on a selection of data published in the last decade and is intended primarily for healthcare professionals. The assessments in clinical trials have been particularly useful for elucidating the effects of various cancers and their treatments on patients' lives and have provided additional information that enhances the usual clinical endpoints used for determining the benefits and toxicity of treatment. With growing experience the quality of the health-related quality of studies has improved and, in general, recent studies are more likely to be methodologically robust than those that were performed in earlier decades. Health-related quality of life has become a more accurate predictor of survival than some other clinical parameters, such as performance status. The overall outlook for the routine assessment of patient-reported outcomes in clinical trials is assured and, eventually, it is likely to become a standard part of clinical practice. However, there is still a need for a clear method for determining the clinical meaningfulness of changes in scores. The answer will probably come from the greater use of patient-reported outcomes and the consequent growth of experience that is necessary to make such judgements.

Which patient will feel down, which will be happy? The need to study the genetic disposition of emotional states

PURPOSE

In quality-of-life (QL) research, the genetic susceptibility of negative and positive emotions is frequently ignored, taken for granted, or treated as noise. The objectives are to describe: (1) the major findings of studies addressing the heritable and environmental causes of variation in negative and positive emotional states and (2) the major biological pathways of and genetic variants involved in these emotional states.

METHODS

Literature overview.

RESULTS

The heritability estimates for anxiety and depression are 30-40%. Related traits as neuroticism and loneliness are also highly heritable. The hypothalamo-pituitary-adrenal axis is the 'final common pathway' for most depressive symptoms. The many findings of investigated genes are promising but not definitive. Heritability estimates of positive emotional states range between 40 and 50%. Life satisfaction and mental health share common genetic factors with optimism and self-esteem. The prefrontal cortex is a candidate brain area for positive emotional states. Biological and genetic research into positive emotional states is scarce.

CONCLUSION

Genetically informative studies may provide insights into a wide variety of complex questions that traditional QL studies cannot deliver. This insight in turn will help us to design more effective supportive programs that could moderate the outcomes of genetically based predispositions.

I'm so tired: biological and genetic mechanisms of cancer-related fatigue

OBJECTIVE

The goal of this paper is to discuss cancer-related fatigue (CRF) and address issues related to the investigation into potential biological and genetic causal mechanisms. The objectives are to: (1) describe CRF as a component of quality of life (QOL); (2) address measurement issues that have slowed progress toward an understanding of mechanisms underlying this symptom; (3) review biological pathways and genetic approaches that have promise for the exploration of causal mechanisms of CRF; and (4) offer directions for future research.

METHODS

Review, synthesis, and interpretation of the literature.

RESULTS

Until recently, CRF and QOL have been understood primarily as subjective patient-reported experiences. With increased understanding of human genetics, theories and research are being expanded to incorporate biological and genetic understandings of these subjective experiences. Proposed biological and genetic mechanisms of CRF that have been examined include cytokine dysregulation, hypothalamic-pituitary-adrenal (HPA) axis dysfunction, five hydroxy tryptophan (5-HT) neurotransmitter dysregulation, circadian rhythm disruption, alterations in adenosine triphosphate (ATP) and muscle metabolism, and vagal afferent activation. Approaches to the study of genetic mechanisms have also been addressed including candidate genes, genome-wide scanning, and gene expression. Based on the review and synthesis of the literature, directions for future research are proposed.

CONCLUSIONS

Understanding the biological and genetic basis of CRF has the potential to contribute to a more complete understanding of the genetic determinants of QOL.