Association of adult glioma with medical conditions, family and reproductive history

Abstract

A population-based case-control study of 416 histologically diagnosed, incident gliomas in adults was carried out in Melbourne, Australia, to determine whether past medical, family or reproductive histories are risk factors for developing glioma. A total of 422 controls were selected from the Australian electoral roll and matched to cases for age, sex and post code of residence. An increased risk of developing glioma was observed among first-born individuals OR (95% CI) 2.0 (1.4-2.9). It is possible that this effect is due to residual confounding by socio-economic status or that it is a chance finding. Alternatively, it may be that this is due to some other effect linked to the first pregnancy, such as maternal age, birth weight or circumstances of delivery. There was no apparent association between the development of glioma and other neuropsychiatric or general medical conditions or with family history or reproductive history. Allergies (asthma and eczema) were not associated with a decreased risk of glioma, as has previously been suggested. Glioma is the most common primary brain malignancy in adults, accounting for approximately 75% of all primary adult brain tumours (Green et al., 1976). The prognosis is poor, with a median survival of less than 12 months (Axtell et al., 1983;Whittle et al., 1991) and an increasing incidence over the last 30 years (Davis et al., 1991). The causes of glioma are unknown, and related to this, no preventive strategy is available. Although many possible risk factors for brain tumours have been suggested, there is still no dominant hypothesis. A wide range of genetic and environmental factors have been investigated. While some evidence exists implicating certain work chemicals (Burch et al., 1987;Preston-Martin and Mack, 1991;Morrison et al., 1992), investigations of a wide range of genetic and environmental factors have been inconclusive (Burch et al., 1987;Wrensch and Barger, 1990;Schiffer, 1991;Ryan et al., 1992;Zampieri et al., 1994).A role has been suggested for genetic factors in the aetiology of glioma (Schiffer, 1991;Wrensch and Barger, 1990), but this is not consistent in all studies (Choi et al., 1970). This is based on the following: the difference in distribution of ABO blood groups between brain tumour patients and controls (Selverstone and Cooper, 1961;Zampieri et al., 1994), the association of brain tumours with genetically determined disorders (Schiffer, 1991), some evidence of familial aggregation of brain tumours (Schiffer, 1991) and familial clustering of brain tumours with breast and lung cancers (Wrensch and Barger, 1990;Zampieri et al., 1994).A number of exploratory case-control studies have been reported which examine the association of medical conditions, family and reproductive history in cases with glioma and controls. There are few consistent findings. There is some evidence that allergies may decrease the risk of glioma (Hochberg et al., 1990;Ryan et al., 1992;Schlehofer et al., 1992a). Although in one report the authors suggested that the reproductive a...

Hormonal and reproductive factors and risk of glioma: A prospective cohort study

“…Hatch et al, 9 in contrast, observed a statistically significant positive trend with increasing age at first live birth. Our findings also support the literature, which has found no association between menopausal status 7,9,11,12 and risk of glioma. Further, our findings regarding use of oral contraceptives are consistent with those of Huang et al, 10 who likewise reported no association.…”

“…Of the 6 case-control studies [7][8][9][10][11][12] that have examined the relationship between parity and risk of glioma, 5 found no significant association 7,9-12 while one 8 observed a statistically significant inverse association. In addition, Lambe et al, 13 who utilized linked registry data from the Swedish Cancer Registry and a nationwide Fertility Registry to conduct a nested case-control study (1,657 incident cases) of brain tumors within a cohort of 9,942 women, found a statistically significant reduced risk of glioma among ever-parous versus nulliparous women.…”

“…[7][8][9][10][11][12] One cohort study, by Lambe et al, 13 has also examined some of these associations. Parity has been examined as a risk factor for glioma in a number of studies, the findings for which have been mixed, with 5 observing no association 7,9-12 and 2 reporting inverse associations.…”

“…7,9,11,12 Few studies have described the association between other reproductive and hormonal factors and risk of glioma among women. [7][8][9][10][11][12][13] To our knowledge, the association between risk of glioma and age at menarche, menopausal status, use of oral contraceptives and hormone replacement therapy (HRT) use has not been examined in any prospective cohort studies. Given the current lack of data from prospective studies regarding these relationships, we examined the association between reproductive and hormonal factors and glioma risk in a cohort of Canadian women.…”

History of allergies and autoimmune diseases and risk of brain tumors in adults

“…The findings regarding infections and brain tumors, while suggestive of a negative association, are mixed. 5,7,8,18,19 Although available data on a broad range of specific medical disorders are inconsistent, immunologically mediated conditions warrant further investigation as factors that might interfere with brain tumor development.…”