Epidemiology as a basis for legislation: how far should epidemiology go?

Michael Reese Hospital and the Campaign to Warn the US Public of the Long-Term Health Effects of Ionizing Radiation, 1973-1977

In July 1973, a study at the University of Chicago linked radiation treatment during childhood to a variety of diseases, including thyroid cancer. A few months later, a worker at Michael Reese Hospital in Chicago, Illinois found a registry of 5266 former patients who had been treated with radiation during the 1950s and 1960s. Hospital officials decided to contact these patients and arrange for follow-up medical examinations. Media coverage of the hospital's campaign had a snowball effect that prompted more medical institutions to follow suit, resulting in the National Cancer Institute (NCI) launching a nationwide campaign to warn the public and medical community about the late health effects of ionizing radiation. This study describes how the single action of a hospital in Chicago and the media attention it attracted led to a national campaign to warn those who underwent radiation treatment during childhood.

High incidence of benign brain meningiomas among Iranian- born Jews in Israel may be linked to both hereditary and environmental factors

BACKGROUND

Following research demonstrating an increased risk for meningiomas in the Jewish population of Shiraz (Iran) we conducted a cohort analysis of meningiomas among Jews originating in Iran and residing in Israel.

MATERIALS AND METHODS

We use the population-based registry data of the Israeli National Cancer Registry (INCR) for the main analysis. All benign meningioma cases diagnosed in Israel from January 2000 to the end of 2009 were included. Patients that were born in Iran, Iraq, Turkey, Bulgaria and Greece were used for the analysis, whereby we calculated adjusted incidence rates per 100,000 people and computed standardized incidence ratios (SIRs) comparing the Iranian-born to each of the three other groups.

RESULTS

Iranian-born Jews had statistically significant higher meningioma rates rates compared to other Jews originating in Balkan states: 1.46 fold compared to Turkish Jews and 1.86 fold compared to the Bulgaria-Greece group. There was a small increase in risk for the Iranian born group compared to those who were born in Iraq (1.06, not significant).

CONCLUSIONS

Higher rates of meningiomas were seen in Jews originating in Iran that are living in Israel as compared to rates in neighboring countries of origin. These differences can be in part attributed to early life environmental exposures in Iran but probably in larger amount are due to genetic and hereditary factors in a closed community like the Iranian Jews. Some support for this conclusion was also found in other published research.

Possible interaction between ionizing radiation, smoking, and gender in the causation of meningioma

Data on the association between smoking and meningioma are inconsistent. The aim of this study was to assess the role of smoking in radiation- and non-radiation-related meningiomas. The study was designed as a 4-group case-control study, balanced for irradiation, including 160 irradiated meningioma case patients, 145 irradiated control subjects, 82 nonirradiated case patients, and 135 nonirradiated control subjects. The sources of these groups included a cohort of individuals who underwent radiotherapy (mean dose, 1.5 Gy to the brain) during childhood for treatment of tinea capitis, claims filed for radiation damage in the framework of a compensation law, and the Israel Cancer Registry. All tests of statistical significance were 2-sided. A statistically significantly elevated risk of meningioma was found among men who had ever smoked, compared with those who were never smokers (odds ratio [OR], 2.13; 95% confidence interval [CI], 1.09-4.15), increasing with smoking pack-years from 1.67 to 2.69 for <10 to >20 pack-years, respectively. Among women, an interaction between radiation and smoking was observed, expressed by a significant protective effect for meningioma (OR, 0.32; 95% CI, 0.14-0.77), with a strong dose-response association (P < .01) in non-irradiated women and a nonsignificant increased risk of meningioma among those who were irradiated (OR, 1.23; 95% CI, 0.68-2.23). Variation in the association between smoking and meningioma may be explained by effects of distinct host factors, such as past exposure to ionizing radiation and/or hormonal factors.

The tinea capitis campaign in Serbia in the 1950s

In this Historical Review we describe the 1950-59 UNICEF-supported campaign to eliminate tinea capitis, also known as ringworm, in Yugoslavia. Medical treatment for this infectious disease involved the use of ionising radiation. We discuss the possible health implications for the treated population. Data were collected from archive documents, newspapers from the 1950s, Yugoslavian scientific reports, interviews with patients who received treatment, and interviews with physicians who gave treatment during the campaign. The campaign screened 878 659 individuals and treated 49 389. On the basis of Israeli tinea capitis research, late health consequences (mainly cancer in the irradiated area) can be expected in the treated Serbian population. The discovery of treatment records for a substantial number of patients makes public-health action and further research possible. The findings are relevant to the Serbian medical community and populations in other countries that used a radiation-based technique for the treatment of tinea capitis.

Genetic predisposition for the development of radiation-associated meningioma: an epidemiological study

BACKGROUND

Ionising radiation is an established risk factor for meningioma, yet less than 1% of irradiated individuals develop this tumour. Familial aggregation of meningioma is rare. We aimed to assess whether genetic factors can modify the risk for meningioma formation after the initiating effect of radiation, by comparison of the frequency of meningiomas in families that included irradiated and unirradiated siblings.

METHODS

This study was based on a larger epidemiological, genetic case-control study, and included 525 families that were divided according to irradiation and disease status of each of the family's index participant: 160 had radiation-associated meningioma (RAM); 145 were irradiated and did not develop meningioma; 85 had meningioma with no previous history of irradiation; and 135 were unirradiated and did not develop meningioma. Data were collected by questionnaires.

FINDINGS

We found additional first-degree relatives with meningioma in 17 families (11%) in the RAM group, whereas only between one and two such families (1%) were found in the other groups (p<0.0001). All meningiomas seen in the families of the RAM group were in irradiated participants. Also, 22 families (10%) in the RAM group had members with cancers in irradiated sites (including head, neck, and chest) compared with 9 (5%) of irradiated controls (p=0.04).

INTERPRETATION

This dataset of families, which included irradiated and unirradiated, and also affected and unaffected family members, created a natural experiment. Our results support the idea that genetic susceptibility increases the risk of developing meningioma after exposure to radiation. Further studies are needed to identify the specific genes involved in this familial sensitivity to ionising radiation. DNA repair and cell-cycle control genes, such as the ataxia-telangiectasia gene, could be plausible candidates for investigation.

Risk of thyroid cancer after childhood exposure to ionizing radiation for tinea capitis

BACKGROUND

The thyroid gland is known to be sensitive to the carcinogenic effect of ionizing radiation, especially in children. The role of potential modifiers of the risk and latency period effects needs further investigation. We examined the effect of low doses of ionizing radiation (4.5-49.5 cGy) on the risk of developing thyroid cancer after long latent periods of up to 54 yr after childhood exposure.

METHODS

The study population included 10,834 individuals irradiated against tinea capitis in the 1950s and two matched nonirradiated groups (general population and siblings) for comparison. Cancer statistics and vital status data were obtained from national registries, updated to December 2002. Excess relative and absolute risks [excess relative risk per gray (ERR/Gy), excess absolute risk (EAR)] were estimated using Poisson regression for survival analysis.

RESULTS

Within the study period, 159 cases of thyroid cancer were diagnosed. Total ERR/Gy and excess absolute risk per gray per 10(4) person-years for developing thyroid cancer reached 20.2 (95% confidence interval 11.8-32.3) and 9.9 (95% confidence interval 5.7-14.7), respectively. The risk was positively associated with dose and negatively associated with age at exposure. ERR/Gy was significantly elevated 10-19 yr after exposure, peaking at 20-30 yr, and decreasing dramatically (although still significantly elevated) 40 yr after exposure.

CONCLUSIONS

Our findings agree with patterns of risk modification seen in most studies of radiation-induced thyroid cancer, although risk per unit dose seems higher. Our data show that 40 yr after irradiation, ERR decreases dramatically, although remaining significantly elevated. The hypothesis of different genetic susceptibility of the Jewish population deserves further exploration.

Genotyping of patients with sporadic and radiation-associated meningiomas

Ionizing radiation is the most established risk factor for meningioma formation. Our aim was to evaluate the main effect of selected candidate genes on the development of meningioma and their possible interaction with ionizing radiation in the causation of this tumor. The total study population included 440 cases and controls: 150 meningioma patients who were irradiated for tinea capitis in childhood, 129 individuals who were similarly irradiated but did not develop meningioma, 69 meningioma patients with no previous history of irradiation, and 92 asymptomatic population controls. DNA from peripheral blood samples was genotyped for single nucleotide polymorphisms (SNP) in 12 genes: NF2, XRCC1, XRCC3, XRCC5, ERCC2, Ki-ras, p16, cyclin D1, PTEN, E-cadherin, TGFB1, and TGFBR2. SNP analysis was done using the MassArray system (Sequenom, San Diego, CA) and computerized analysis by SpectroTYPER. Logistic regressions were applied to evaluate main effect of each gene on meningioma formation and interaction between gene and radiation. Intragenic SNPs in the Ki-ras and ERCC2 genes were associated with meningioma risk (odds ratio, 1.76; 95% confidence interval, 1.07-2.92 and odds ratio, 1.68; 95% confidence interval, 1.00-2.84, respectively). A significant interaction was found between radiation and cyclin D1 and p16 SNPs (P for interaction = 0.005 and 0.057, respectively). Our findings suggest that Ki-ras and ERCC2 SNPs are possible markers for meningioma formation, whereas cyclin D1 and p16 SNPs may be markers of genes that have an inverse effect on the risk to develop meningioma in irradiated and nonirradiated populations.

A possible association between ionizing radiation and pituitary adenoma: a descriptive study

BACKGROUND

Despite the recognition of ionizing radiation as a causal risk factor for a variety of solid tumors (including brain tumors), to date, such an association with pituitary adenoma (PA) has not been demonstrated.

METHODS

To evaluate a possible association between past exposure to radiation and the occurrence of PA, the authors reviewed about 4900 medical records of patients who had been irradiated in childhood for tinea capitis. An additional search for patients was performed using the Israel Cancer Registry. The average radiation dose to the pituitary gland was estimated as 0.56 grays, and, for all patients, a meticulous validation of the irradiation was performed.

RESULTS

A group of 16 patients who developed symptomatic PA after childhood exposure to radiotherapy were identified. Overall, the clinical and demographic characteristics of these patients were similar to other series reported in the literature. There was an apparently high rate of second primary tumors (25%), all of them in the irradiated area, diagnosed among this group. The methodologic issues that limit the demonstration of a possible association between radiation and PA and the epidemiologic and experimental findings in the literature are discussed.

CONCLUSIONS

In view of the ample amount of evidence identifying low-dose ionizing radiation as a risk factor for a number of intracranial tumors as well as for tumors arising in endocrine organs, a radiation immunity of the pituitary gland is difficult to accept. Hence, the authors suggest that this series should be considered as preliminary observation that supports the role of ionizing radiation in the development of this tumor.

A global review of legislation on HIV/AIDS: the issue of HIV testing

OBJECTIVE

Critical review of worldwide legislation on HIV/AIDS, with a focus on the issue of HIV testing, mainly in a military context.

DESIGN

Analysis of health legislation on HIV/AIDS among 121 of the 191 member states of the World Health Organization (WHO), representing 85% of the world's population.

METHODS

The WHO Directory of Legal Instruments Dealing with HIV Infection and AIDS has been the main source consulted. Relevant findings of two global surveys were used to examine HIV testing in the military.

RESULTS

AIDS cases are reportable in 60% of the 121 countries, whereas HIV infections in no more than 26%. Notifications are kept confidential by law in 20% of countries. Only 17% have developed HIV-specific legislation against social discrimination, whereas 10% have passed legislation establishing financial reimbursement to those who have acquired HIV infection after injection of HIV-contaminated biologic material, support for occupational risk, and/or social protection for patients. Only 42% of the 121 countries report having legal instruments that require screening of donated blood. Legislative measures that address, generally in a prescriptive but sometimes also in a protective way, vulnerable groups, such as commercial sex workers, men who have sex with men, injecting drug users, and recipients of multiple transfusions of blood or blood-derivatives, are reported in 27% of countries. Other categories considered potentially vulnerable, for which specific legislation has been passed, include immigrants (17% of countries), prisoners (5%), and health personnel (14%). Further legislative measures for HIV prevention address testing pregnant women in the prenatal period (7% of countries), supporting condom promotion (11%), measures requiring quarantine, isolation, or coercive hospitalization of HIV-infected people or AIDS patients (9%), or imposing penal sanctions for HIV-infected people who deliberately expose others to the risk of transmission (10%). A National AIDS Committee responsible for addressing issues related to HIV/AIDS has been established by law in 39% of the 121 countries. Global surveys show that 27 countries carry out compulsory HIV screening on recruitment of military personnel.

CONCLUSIONS

These data represent a useful tool to make governments aware of the problem of underreporting of legal instruments to the WHO and of the need to promote legislation in line with the idea that public health and human rights are complementary, not conflicting, goals.