Association between adult height, genetic susceptibility and risk of glioma

Prospective investigation of herpesvirus infection and risk of glioma

Glioma is an aggressive neoplasm of the brain with poorly understood etiology. A limited number of pathogens have been examined as glioma risk factors, but data from prospective studies with infection status determined before disease are lacking. Herpesviruses comprise a large family of DNA viruses that infect humans and are linked to a range of chronic diseases. We conducted a prospective evaluation of the association between antibody to six human herpesviruses and glioma risk in the Janus Serum Bank (Janus) and the Cancer Prevention Study-II (CPS-II). In Janus and CPS-II, the risk for glioma was not related to seroprevalence of herpes simplex virus-1, varicella zoster virus, or human herpes viruses 6A or 6B. In Janus, seropositivity to either the Epstein Barr virus (EBV) EA[D] or VCAp18 antigen was associated with a lower risk of glioma (ORs: 0.55 [95% CI 0.32-0.94] and 0.57 [95% CI 0.38-0.85]). This inverse association was consistent by histologic subtype and was observed for gliomas diagnosed up to two decades following antibody measurement. In Janus, seropositivity to at least one of three examined cytomegalovirus (CMV) antigens (pp150, pp52, pp28) was associated with an increased risk of nonglioblastoma (OR: 2.08 [95% CI 1.07-4.03]). This association was limited to tumors diagnosed within 12 years of antibody measurement. In summary, we report evidence of an inverse association between exposure to EBV and glioma. We further report that CMV exposure may be related to a higher likelihood of the nonglioblastoma subtype.

The impact of body mass index and height on risk for primary tumours of the spinal cord, spinal meninges, spinal and peripheral nerves in 1.7 million norwegian women and men: a prospective cohort study

BACKGROUND

Primary tumours of the spinal cord, spinal meninges, spinal and peripheral nerves comprise a heterogenous group of pathology, dominantly represented by meningioma, nerve sheath tumours (NST) and glioma. Body height and body mass index (BMI) are risk factors for certain brain tumour subgroups, but no other study has specifically assessed height and BMI in relation to primary tumours of the spine and peripheral nerves in women and men.

METHODS

In this prospective population-based cohort study height and weight were measured in 1.7 million adult Norwegian women and men at baseline. Incident cases of primary tumours arising from the spinal cord, spinal meninges, spinal and peripheral nerves during follow-up were identified by linkage to the National Cancer Registry. Tumour risk was assessed by Cox regression analyses in relation to height and BMI.

RESULTS

During 49 million person-years of follow-up, 857 primary tumours of the spinal cord, spinal meninges, spinal and peripheral nerves were identified. Overweight and obesity were not associated with risk for all tumours or any tumour subgroup. Height was positively associated with risk for all tumours (HR per 10 cm increase: 1.30, 95% CI 1.16-1.46). The association between height and tumour risk varied between tumour subgroups: while height was not significantly associated with NST, height increased the risk for meningioma (HR 1.42, 95% CI 1.13-1.78) and glioma (HR 1.56, 95% CI 1.06-2.28). The strongest association between height and tumour risk was found for the glioma subgroup of ependymoma in women (HR 3.38, 95% CI 1.64-6.94).

CONCLUSION

This study could not identify overweight and obesity as risk factors for primary tumours of the spinal cord, spinal meninges, spinal and peripheral nerves in women or men. Increasing body height was associated with increased tumour risk overall, but not universal for all tumour subgroups.Importance of the studyPrimary tumours of the spinal cord, spinal meninges, spinal and peripheral nerves have received little focus in epidemiologic studies, although the incidence and histo-pathological tumour subgroups differ significantly from primary brain tumours. Risk factors for these tumours have hardly been assessed in previous studies. Height, overweight and obesity are known risk factors for several cancers, including certain brain tumour subgroups, such as meningioma.This is the first study to report the association between height, overweight and obesity and primary tumours of the spinal cord, spinal meninges, spinal and peripheral nerves. This includes tumour subgroups of meningioma, nerve sheath tumour, glioma and the most common spinal glioma subgroup of ependymoma. While overweight and obesity were not associated with either of the tumour subgroups, an association between increasing body height and risk for spinal meningioma and glioma, including ependymoma, was found. Nerve sheath tumour risk was not associated with increasing body height.

Association between height and the risk of primary brain malignancy in adults: a nationwide population-based cohort study

Background

The association between height and the risk of developing primary brain malignancy remains unclear. We evaluated the association between height and risk of primary brain malignancy based on a nationwide population-based database of Koreans.

Methods

Using data from the Korean National Health Insurance System cohort, 6 833 744 people over 20 years of age that underwent regular national health examination were followed from January 2009 until the end of 2017. We documented 4771 cases of primary brain malignancy based on an ICD-10 code of C71 during the median follow-up period of 7.30 years and 49 877 983 person-years.

Results

When dividing the population into quartiles of height for each age group and sex, people within the highest height quartile had a significantly higher risk of brain malignancy, compared to those within the lowest height quartile (HR 1.21 CI 1.18–1.32) after adjusting for potential confounders. We also found that the risk of primary brain malignancy increased in proportion with the quartile increase in height. After analyzing subgroups based on older age (≥ 65) and sex, we found positive relationships between height and primary brain malignancy in all subgroups.

Conclusions

This study is the first to suggest that height is associated with an increased risk of primary brain malignancy in the East-Asian population. Further prospective and larger studies with precise designs are needed to validate our findings.

Height in adolescence as a risk factor for glioma subtypes: a nationwide retrospective cohort study of 2.2 million subjects

BACKGROUND

Gliomas manifest in a variety of histological phenotypes with varying aggressiveness. The etiology of glioma remains largely unknown. Taller stature in adulthood has been linked with glioma risk. The aim of this study was to discern whether this association can be detected in adolescence.

METHODS

The cohort included 2 223 168 adolescents between the ages of 16 and 19 years. Anthropometric measurements were collected at baseline. Incident cases of glioma were extracted from the Israel National Cancer Registry over a follow-up period spanning 47 635 745 person-years. Cox proportional hazard models were used to estimate the hazard ratio (HR) for glioma and glioma subtypes according to height, body mass index (BMI), and sex.

RESULTS

A total of 1195 patients were diagnosed with glioma during the study period. Mean (SD) age at diagnosis was 38.1 (11.7) years. Taller adolescent height (per 10-cm increase) was positively associated with the risk for glioma of any type (HR: 1.15; P = .002). The association was retained in subgroup analyses for low-grade glioma (HR: 1.17; P = .031), high-grade glioma (HR: 1.15; P = .025), oligodendroglioma (HR: 1.31; P = .015), astrocytoma (HR: 1.12; P = .049), and a category of presumed IDH-mutated glioma (HR: 1.17; P = .013). There was a trend toward a positive association between height and glioblastoma, however this had borderline statistical significance (HR: 1.15; P = .07). After stratification of the cohort by sex, height remained a risk factor for men but not for women.

CONCLUSIONS

The previously established association between taller stature in adulthood and glioma risk can be traced back to adolescence. The magnitude of association differs by glioma subtype.

Toxoplasma gondii infection and the risk of adult glioma in two prospective studies

Toxoplasma gondii (T gondii) is a common parasite that shows affinity to neural tissue and may lead to the formation of cysts in the brain. Previous epidemiologic studies have suggested an association between glioma and increased prevalence of T gondii infection, but prospective studies are lacking. Therefore, we examined the association between prediagnostic T gondii antibodies and risk of glioma in two prospective cohorts using a nested case-control study design. Cases and matched controls were selected from the American Cancer Society's Cancer Prevention Study-II Nutrition Cohort (CPSII-NC) (n = 37 cases and 74 controls) and the Norwegian Cancer Registry's Janus Serum Bank (Janus) (n = 323 cases and 323 controls). Blood samples collected prior to diagnosis were analyzed for antibodies to two T gondii surface antigens (p22 and sag-1), with individuals considered seropositive if antibodies to either antigen were detected. Conditional logistic regression was used to calculate odds ratios (OR) and 95% confidence intervals (95% CI) for each cohort. In both cohorts, a suggestive increase in glioma risk was observed among those infected with T gondii (OR: 2.70; 95% CI: 0.96-7.62 for CPSII-NC; OR: 1.32, 95% CI: 0.85-2.07 for Janus), particularly among participants with high antibody titers specific to the sag-1 antigen (CPSII-NC OR: 3.35, 95% CI: 0.99-11.38; Janus OR: 1.79, 95% CI: 1.02-3.14). Our findings provide the first prospective evidence of an association between T gondii infection and risk of glioma. Further studies with larger case numbers are needed to confirm a potential etiologic role for T gondii in glioma.

Prospective investigation of polyomavirus infection and the risk of adult glioma

Glioma is an aggressive primary tumor of the brain with a poorly understood etiology. We studied the association of 4 human polyomaviruses (HPyV)—JC virus (JCV), BK virus (BKV), human polyomavirus 6 (HPyV6), and Merkel cell polyomavirus (MCPyV) with glioma risk within the Cancer Prevention Study II in the US (CPS-II) and the Janus Serum Bank in Norway. Cohort participants subsequently diagnosed with glioma from the CPS-II (n = 37) and Janus Serum Bank (n = 323), a median of 6.9 and 15.4 years after blood collection, respectively, were matched to individual controls on age, sex, and date of blood draw. Serum antibodies to the major viral capsid protein (VP1) were used to establish infection history for each polyomavirus. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using conditional logistic regression. In the Janus Serum Bank, MCPyV infection was associated with a higher risk of glioma overall (OR: 1.56; 95% CI 1.10, 2.19). A modest, nonsignificant positive association with MCPyV infection was also observed in CPS-II (OR: 1.29; 95% CI 0.54, 3.08). In both cohorts, glioma risk was not significantly related to infection with JCV, BKV or HPyV6. The present study suggests that MCPyV infection may increase glioma risk.

Epidemiology of Anthropometric Factors in Glioblastoma Multiforme-Literature Review

Although glioblastoma multiforme (GBM) is a widely researched cancer of the central nervous system, we still do not know its full pathophysiological mechanism and we still lack effective treatment methods as the current combination of surgery, radiotherapy, and chemotherapy does not bring about satisfactory results. The median survival time for GBM patients is only about 15 months. In this paper, we present the epidemiology of central nervous system (CNS) tumors and review the epidemiological data on GBM regarding gender, age, weight, height, and tumor location. The data indicate the possible influence of some anthropometric factors on the occurrence of GBM, especially in those who are male, elderly, overweight, and/or are taller. However, this review of single and small-size epidemiological studies should not be treated as definitive due to differences in the survey methods used. Detailed epidemiological registers could help identify the main at-risk groups which could then be used as homogenous study groups in research worldwide. Such research, with less distortion from various factors, could help identify the pathomechanisms that lead to the development of GBM.

Body mass index and height in relation to brain tumor risk in a Japanese population

PURPOSE

Although height and body mass index (BMI) are reported to be positively associated with several common cancers, evidence regarding their association with brain tumor risk remains sparse, particularly in Asian populations. In this study, we analyzed the association between height and BMI and brain tumor risk in a Japanese population using a large population-based prospective cohort study.

METHODS

A total of 102,925 participants (48,213 men and 54,712 women) enrolled in the Japan Public Health Center-based Prospective Study were followed from baseline, namely 1990 for cohort I and 1993 for cohort II, until 2012. Information on participants' dietary and lifestyle habits, including height and body weight, was collected through survey questionnaires administered at baseline. We used the Cox proportional hazards regression model to estimate hazard ratios and 95% confidence intervals (CIs) for brain tumor incidence, with adjustment for potential confounding variables.

RESULTS

During an average follow-up of 18.1 years, 157 (70 men and 87 women) cases of brain tumor were newly diagnosed. BMI showed a statistically insignificant positive association with the risk of brain tumor. In addition, statistically significant positive trends were seen for men and meningioma, with multivariable-adjusted hazard ratios for a BMI of 27.5 to less than 40 versus 18.5 to less than 23 kg per m² of 2.14 (95% CI = 0.99-4.59) (P = 0.03) and 1.98 (95% CI = 0.84-4.67) (P = 0.046), respectively. In contrast, height showed no clear association with brain tumor risk, overall or in subgroup analysis.

CONCLUSIONS

Compared with a BMI of 18 to less than 23.5 kg per m², a higher BMI was associated with higher risk of brain tumor, particularly in men and with meningioma.

The Influence of Nutritional and Lifestyle Factors on Glioma Incidence

Cancers are the first main cause of premature death in developed countries. Since brain tumors, especially gliomas, are the most lethal type of cancers, risk factors for their prevalence are still being discussed. Nearly 30–50% of all cancers could be prevented by proper nutritional habits and other lifestyle factors, but their influence on the tumors of the central nervous system has not been explained completely and still requires further studies. That is why we attempted to review the available research in this field, with a special focus on the factors with the proven protective activity observed in other cancers. Adequate vegetables and antioxidants (such as vitamins C and A) provided with a diet could have a protective effect, while other factors have shown no correlation with the incidence of glioma. However, further studies are necessary to determine whether fish, coffee, and tea consumption may prevent glioma. Maintaining proper body weight and undertaking a sufficient level of daily physical activity also seem to be important. Excessive body mass index (BMI) and higher attained height have increased the risk of glioma. In order to link more accurately the chosen factors to the prevalence of gliomas, it seems necessary to conduct large cohort, prospective, controlled studies in different world regions.

The SHORT Score for Preoperative Assessment of the Risk for Short-Term Survival in Glioblastoma

BACKGROUND

Despite recent improvements in treatment of glioblastoma (GBM), some patients still have a short survival. We sought to develop a new risk score for preoperative assessment of short-term survival (STS) (<6 months) in patients with GBM.

METHODS

All adult patients who underwent surgical resection of GBM between 2004 and 2014 were included (N = 379). Demographic and clinical parameters, which were available at admission, were assessed. Variables were evaluated in univariate and multivariate analyses. The score was validated in a separate cohort of patients with GBM who underwent surgical resection between 2015 and 2018.

RESULTS

The following independent predictors of STS were integrated into a new score: body height (<169 cm, 1 point), arterial hypertension (1 point), age (≤54 years, 0 points; 55-74 years, 1 points; ≥75 years, 2 points), and poor clinical status (Karnofsky performance scale [KPS] score: ≤60%, 2 points; 70%-80%, 1 point; ≥90%, 0 points). The new risk score, SHORT (Small body height, Hypertension, Older age, Reduced KPS score, short-Term survival), ranged from 0 to 6 points and showed good accuracy of risk estimation for STS in GBM (area under the curve: 0.715). STS rates were 9.7%, 23.1%, and 70% in patients with GBM scoring <2 points, 2-4 points, and >4 points (P < 0.0001). The score was successfully validated (area under the curve: 0.770).

CONCLUSIONS

This study presents the SHORT score for preoperative assessment of STS risk in patients with GBM. This risk score needs external validation in larger patient cohorts from other institutions. Our score might be a tool to facilitate treatment decisions in patients with GBM before surgery.

Does risk of brain cancer increase with intracranial volume? A population-based case control study

Background

Glioma is the most common primary brain tumor and is believed to arise from glial stem cells. Despite large efforts, there are limited established risk factors. It has been suggested that tissue with more stem cell divisions may exhibit higher risk of cancer due to chance alone. Assuming a positive correlation between the number of stem cell divisions in an organ and size of the same organ, we hypothesized that variation in intracranial volume, as a proxy for brain size, may be linked to risk of high-grade glioma.

Methods

Intracranial volume was calculated from pretreatment 3D T1-weighted MRI brain scans from 124 patients with high-grade glioma and 995 general population-based controls. Binomial logistic regression analyses were performed to ascertain the effect of intracranial volume and sex on the likelihood that participants had high-grade glioma.

Results

An increase in intracranial volume of 100 mL was associated with an odds ratio of high-grade glioma of 1.69 (95% CI: 1.44‒1.98; P < 0.001). After adjusting for intracranial volume, female sex emerged as a risk factor for high-grade glioma (odds ratio for male sex = 0.56, 95% CI: 0.33‒0.93; P = 0.026).

Conclusions

Intracranial volume is strongly associated with risk of high-grade glioma. After correcting for intracranial volume, risk of high-grade glioma was higher in women. The development of glioma is correlated to brain size and may to a large extent be a stochastic event related to the number of cells at risk.

The impact of body mass index and height on the risk for glioblastoma and other glioma subgroups: a large prospective cohort study

Background

Glioma comprises a heterogeneous group of mostly malignant brain tumors, whereof glioblastoma (GBM) represents the largest and most lethal subgroup. Body height and body mass index (BMI) are risk factors for other cancers, but no previous study has examined anthropometric data in relation to different glioma subgroups.

Methods

This prospective cohort study includes 1.8 million Norwegian women and men between ages 14 and 80 years at baseline. Body weight and height were measured, and incident cases of glioma were identified by linkage to the National Cancer Registry. Cox regression analyses were performed to evaluate risk for different glioma subgroups in relation to anthropometric measures.

Results

During 54 million person-years of follow-up, 4,382 gliomas were identified. Overweight and obesity were not associated with risk for any glioma subgroup. Height was positively associated with risk for GBM and all other gliomas (hazard ratio [HR] per 10 cm increase: 1.24; 95% confidence interval [CI], 1.17-1.31 and 1.18; 95% CI, 1.09-1.29) but not with the proxy for isocitrate dehydrogenase (IDH)-mutant glioma (HR, 1.09; 95% CI, 0.98-1.21). In further subgroup analyses, the effect of height on glioma risk varied significantly with positive associations for oligoastrocytoma (HR, 1.74; 95% CI, 1.20-2.53) and malignant glioma not otherwise specified (NOS) (HR, 1.42; 95% CI, 1.16-1.76, but not with diffuse astrocytoma (WHO grades II and III) or oligodendroglioma.

Conclusion

This epidemiologic study consolidates height as a risk factor for GBM and other gliomas. It further indicates that this association is not universal for gliomas but may differ between different glioma subgroups.

Overweight, obesity and height as risk factors for meningioma, glioma, pituitary adenoma and nerve sheath tumor: a large population-based prospective cohort study

BACKGROUND

In 2016, the International Agency for Research on Cancer (IARC) has announced that avoiding body fatness (i.e. overweight and obesity) contributes to prevent meningioma occurrence, but considered the available evidence for glioma inadequate. The association of body fatness with other CNS tumor subgroups is largely unknown.

OBJECTIVES

To assess whether body fatness or body height are associated with risk for meningioma, glioma, pituitary adenoma (PA) or nerve sheath tumor (NST) in a large population-based Norwegian cohort.

METHODS

In this prospective cohort study of 1.8 million Norwegian residents, weight and height were measured at baseline and incident intracranial tumors were subsequently identified by linkage to the Cancer Registry of Norway. Cox regression analyses were performed to estimate risk for each tumor subgroup in relation to anthropometric measures, stratified by sex and in different age groups.

RESULTS

During 54 million person-years of follow-up 3335 meningiomas, 4382 gliomas, 1071 PAs and 759 NSTs were diagnosed. Obesity (BMI ≥30 kg/m²) was not associated with risk for meningioma or glioma, but was significantly associated with risk for PA (HR 1.43; 95% CI 1.09-1.88) compared with the reference group (BMI 20-24.9 kg/m²). For intracranial NSTs, obesity was associated with reduced tumor risk (HR 0.68; 95% CI 0.46-0.99). Body height was associated with increased risk for all four tumor subgroups.

CONCLUSIONS

This study does not confirm overweight or obesity as risk factors for meningioma. Additionally, overweight and obesity can be quite confidently excluded as risk factors for glioma. However, this study indicates that body fatness increases the risk for PA, while it reduces the risk for NST.

Older age at the completion of linear growth is associated with an increased risk of adult glioma

PURPOSE

To examine the association of age when adult height was attained with glioma risk.

METHODS

We analyzed data from a US-based case-control study of glioma risk factors. Logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals (CI) associated between age at attainment of adult height and glioma risk. Multivariate models were adjusted for age, race, sex, education, and state of residence. We examined associations overall, and according to glioma grade, sex, and final adult height.

RESULTS

The study set included n = 951 controls and n = 776 cases, with a median age of 56 (18-92); the majority was male (53.8%) and identified as Caucasian. Older age at height completion was associated with an increased risk of glioma. A significant positive trend was observed both for glioblastoma (OR 1.10; 95% CI 1.04-1.17 per 1-year increase in age) and lower grade non-glioblastoma subtypes combined (OR 1.18; 95% CI 1.10-1.28 per year increase in age). The association was observed in men and women, and in all categories of final adult height.

CONCLUSIONS

We observed for the first time a positive association between glioma risk and a prolonged adolescent growth phase. Our results suggest a role for factors governing the timing and intensity of growth in adolescence as risk-determining exposures in adult glioma.

Anthropometrics at birth and risk of a primary central nervous system tumour: A systematic review and meta-analysis

BACKGROUND

The aetiology of primary central nervous system (CNS) tumours remains largely unknown, but their childhood peak points to perinatal parameters as tentative risk factors. In this meta-analysis, we opted to quantitatively synthesise published evidence on the association between birth anthropometrics and risk of primary CNS tumour.

METHODS

Eligible studies were identified via systematic literature review; random-effects meta-analyses were conducted for the effect of birth weight and size-for-gestational-age on childhood and adult primary CNS tumours; subgroup, sensitivity, meta-regression and dose-response by birth weight category analyses were also performed.

RESULTS

Forty-one articles, encompassing 53,167 CNS tumour cases, were eligible. Birth weight >4000 g was associated with increased risk of childhood CNS tumour (OR: 1.14, [1.08-1.20]; 22,330 cases). The risk was higher for astrocytoma (OR: 1.22, [1.13-1.31]; 7456 cases) and embryonal tumour (OR: 1.16, [1.04-1.29]; 3574 cases) and non-significant for ependymoma (OR: 1.12, [0.94-1.34]; 1374 cases). Increased odds for a CNS tumour were also noted among large-for-gestational-age children (OR: 1.12, [1.03-1.22]; 10,339 cases), whereas insufficient data for synthesis were identified for other birth anthropometrics. The findings remained robust across subgroup and sensitivity analyses controlling for several sources of bias, whereas no significant heterogeneity or publication bias were documented. The limited available evidence on adults (4 studies) did not reveal significant associations between increasing birth weight (500-g increment) and overall risk CNS tumour (OR: 0.99, [0.98-1.00]; 1091 cases) or glioma (OR: 1.03, [0.98-1.07]; 2052 cases).

CONCLUSIONS

This meta-analysis confirms a sizeable association of high birth weight, with childhood CNS tumour risk, particularly astrocytoma and embryonal tumour, which seems to be independent of gestational age. Further research is needed to explore underlying mechanisms, especially modifiable determinants of infant macrosomia, such as gestational diabetes.

A systematic SNP selection approach to identify mechanisms underlying disease aetiology: linking height to post-menopausal breast and colorectal cancer risk

Data from GWAS suggest that SNPs associated with complex diseases or traits tend to co-segregate in regions of low recombination, harbouring functionally linked gene clusters. This phenomenon allows for selecting a limited number of SNPs from GWAS repositories for large-scale studies investigating shared mechanisms between diseases. For example, we were interested in shared mechanisms between adult-attained height and post-menopausal breast cancer (BC) and colorectal cancer (CRC) risk, because height is a risk factor for these cancers, though likely not a causal factor. Using SNPs from public GWAS repositories at p-values < 1 × 10⁻⁵ and a genomic sliding window of 1 mega base pair, we identified SNP clusters including at least one SNP associated with height and one SNP associated with either post-menopausal BC or CRC risk (or both). SNPs were annotated to genes using HapMap and GRAIL and analysed for significantly overrepresented pathways using ConsensuspathDB. Twelve clusters including 56 SNPs annotated to 26 genes were prioritised because these included at least one height- and one BC risk- or CRC risk-associated SNP annotated to the same gene. Annotated genes were involved in Indian hedgehog signalling (p-value = 7.78 × 10⁻⁷) and several cancer site-specific pathways. This systematic approach identified a limited number of clustered SNPs, which pinpoint potential shared mechanisms linking together the complex phenotypes height, post-menopausal BC and CRC.

Socioeconomic status and glioblastoma risk: a population-based analysis

PURPOSE

Socioeconomic status (SES) is associated with risk of various cancer types because of correlation between SES and causal factors or increased case ascertainment, or both. Studies evaluating the association between glioblastoma and occupational or SES factors have yielded inconsistent results. We evaluated the association between SES and glioblastoma risk using a large, population-based cancer registry dataset.

METHODS

Data of the Surveillance, Epidemiology, and End Results Program were used to evaluate the impact of SES on glioblastoma risk. SES was divided into quintiles on the basis of census tract of residence. Census tracts are small, geographically defined areas with relatively homogeneous population characteristics.

RESULTS

Higher SES was strongly associated with increased risk of glioblastoma (p < .001). Relative to persons living in census tracts of the lowest SES quintile, the highest SES quintile had a rate ratio of 1.45 (95 % CI 1.39-1.51) (p < .001). Similar associations were seen in population subgroups defined by age, sex, and race.

CONCLUSIONS

The strong association between higher SES and greater glioblastoma risk is unlikely to represent an ascertainment effect because glioblastoma is rapidly progressive and ultimately fatal. A number of previously proposed glioma risk factors may be correlated with SES, including atopy and allergy rates, cellular telephone use, and body morphometric measures. Further research is needed to define the mechanism of this association.

A prospective study of height and body mass index in childhood, birth weight, and risk of adult glioma over 40 years of follow-up

Greater attained height and greater body mass index (BMI; weight (kg)/height (m)(2)) in young adulthood have been associated with glioma risk, but few studies have investigated the association with body size at birth or during childhood, when the brain undergoes rapid cell growth and differentiation. The Copenhagen School Health Records Register includes data on 320,425 Danish schoolchildren born between 1930 and 1989, with height and weight measurements from ages 7-13 years and parentally recorded birth weights. We prospectively evaluated associations between childhood height and BMI, birth weight, and adult glioma risk. During follow-up (1968-2010), 355 men and 253 women aged ≥18 years were diagnosed with glioma. In boys, height at each age between 7 and 13 years was positively associated with glioma risk; hazard ratios per standard-deviation score at ages 7 (approximately 5.1 cm) and 13 (approximately 7.6 cm) years were 1.17 (95% confidence interval (CI): 1.05, 1.30) and 1.21 (95% CI: 1.09, 1.35), respectively. No associations were observed for childhood height in girls or for BMI. Birth weight was positively associated with risk (per 0.5 kg: hazard ratio = 1.13, 95% CI: 1.04, 1.24). These results suggest that exposures associated with higher birth weight and, in boys, greater height during childhood may contribute to the etiology of adult glioma.

Epidemiologic and molecular prognostic review of glioblastoma

Glioblastoma multiforme (GBM) is the most common and aggressive primary central nervous system malignancy with a median survival of 15 months. The average incidence rate of GBM is 3.19/100,000 population, and the median age of diagnosis is 64 years. Incidence is higher in men and individuals of white race and non-Hispanic ethnicity. Many genetic and environmental factors have been studied in GBM, but the majority are sporadic, and no risk factor accounting for a large proportion of GBMs has been identified. However, several favorable clinical prognostic factors are identified, including younger age at diagnosis, cerebellar location, high performance status, and maximal tumor resection. GBMs comprise of primary and secondary subtypes, which evolve through different genetic pathways, affect patients at different ages, and have differences in outcomes. We report the current epidemiology of GBM with new data from the Central Brain Tumor Registry of the United States 2006 to 2010 as well as demonstrate and discuss trends in incidence and survival. We also provide a concise review on molecular markers in GBM that have helped distinguish biologically similar subtypes of GBM and have prognostic and predictive value.

Reproductive factors and risk of primary brain tumors in women

Gender-specific incidence patterns and the presence of hormonal receptors on tumor cells suggest that sex hormones may play a role in the onset of primary brain tumors. However, epidemiological studies on the relation of hormonal risk factors to the risk of brain tumors have been inconsistent. We examined the role of reproductive factors in the onset of glioma and meningioma in a case-control study conducted in the Southeastern US that included 507 glioma cases, 247 meningioma cases, and 695 community-based and friend controls. Unconditional logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CI) adjusting for age, race, US state of residence, and education. An older age at menarche was associated with an increased risk of glioma (≥ 15 vs. ≤ 12 years: OR 1.65; 95% CI 1.11-2.45), with a stronger association observed in pre-menopausal (OR 2.22; 95% CI 1.12-4.39) than post-menopausal (OR 1.55; 95% CI 0.93-2.58) women. When compared to controls, meningioma cases were more likely to have undergone natural menopause (OR 1.52; 95% CI 1.04-2.21) whereas glioma cases were less likely to be long term users of oral contraceptives (OR 0.47; 95% CI 0.33-0.68). Increasing parity was not related to the risk of either tumor. Current findings are consistent with a limited role for hormones in the onset of brain tumors in women. Results contribute to a growing body of evidence that a later age at menarche increases the risk of glioma in women.

Anthropometric factors in relation to risk of glioma

INTRODUCTION

Increased height and greater adiposity have been linked to an increased risk of many cancer types, though few large studies have examined these associations in glioma. We examined body weight and height as potential risk factors for glioma in a large US-based case-control study.

METHODS

The analysis included 1,111 glioma cases and 1,096 community controls. In a structured interview, participants reported their height and weight at 21 years of age, lowest and highest weight in adulthood, and weight 1-5 years in the past.

RESULTS

Being underweight at age 21 (BMI < 18.5 kg/m(2)) was inversely associated with the risk of glioma development. This protective association was observed in both men and women, but reached statistical significance in women only (multivariate OR 0.68; 95 % CI 0.48, 0.96). When BMI at age 21 was assessed as a continuous variate, a small but significant increase in risk was observed per unit increase in kg/m(2) (OR 1.04; 95 % CI 1.02, 1.07). Adult height, recent body weight, and weight change in adulthood were not associated with glioma risk. All results were similar among never smokers and were consistent after stratifying by glioma subtype.

CONCLUSION

The present data suggest that a low body weight in early adulthood is associated with a reduced risk of glioma later in life. Results are consistent with previous studies in showing no material association of glioma risk with usual adult body weight. The present study does not support any association of adult stature with glioma risk.