Search PubMed⌕ Search

Biomedical subjects

L J Kinlen

Publications and source records attributed to L J Kinlen.

At least 37 records · Page 2Linked to original sources
PubMed1994

Wartime evacuation and mortality from childhood leukaemia in England and Wales in 1945-9.

OBJECTIVE: To discover whether the wartime government evacuation of children from London and other population centres to rural districts was associated with any increase in childhood leukaemia. DESIGN: Observational study of mortality from leukaemia among the childhood population of England and Wales in relation to the unique population movements during the second world war. The 476 rural districts of England and Wales were ranked according to the ratio of government evacuees (two thirds of them children) to local children in September 1941. The districts were divided into three categories, each with similar numbers of children in 1947 but with different ratios of evacuees to local children ("low," "intermediate," "high"). Mortality from childhood leukaemia was examined in these three rural categories in 1945-9. Urban areas were also examined according to their exposure to evacuees. SETTING: Local authority areas of England and Wales. SUBJECTS: Children aged under 15. RESULTS: 47% excess of leukaemia at ages 0-14 years occurred in 1945-9 in the rural "high" category for evacuees relative to the "low" category, with a significant trend across the three categories. There were increases in both the 0-4 and 5-14 year age groups, but these were larger in the older age group. Rates 25% lower than average occurred in rural areas with few evacuees. CONCLUSION: These findings suggest that wartime evacuation increased the incidence of childhood leukaemia in rural areas and that other forms of population mixing may have contributed to the increases in past decades. Overall, they add to the appreciable evidence for an infective basis in childhood leukaemia.

Adolescent↗
PubMed1994

Leukaemia.

The most striking and consistent trend in leukaemia in different countries since 1950 is the recent decline in mortality in childhood, reflecting the advent of effective methods of treatment in the 1960s. Increases at ages 75-84 in several countries since 1950 are consistent with improvements in cancer registration and in the detail of death certification. However, in the main, these have not persisted into the 1980s. Otherwise, there has been no obvious international pattern, and partly for this reason, the rates have been presented in some detail so that readers can make their own judgment.

Adolescent↗
PubMed1993

Can paternal preconceptional radiation account for the increase of leukaemia and non-Hodgkin's lymphoma in Seascale?

OBJECTIVE: To determine if the excess of leukaemia and non-Hodgkin's lymphoma in Seascale is restricted to those born in the parish and whether it might be explained by the postulated relation with paternal preconceptional radiation. DESIGN: Comparison, separately for those born in the parish and those born elsewhere, of the numbers of these malignancies observed in Seascale with those expected on the basis of reference rates for England and Wales. Details of paternal radiation levels were sought for each case. SETTING: The parish of Seascale in west Cumbria. SUBJECTS: Residents of Seascale below age 25 years in the years 1951-91. MAIN OUTCOME MEASURES: The observed and expected numbers of cases of leukaemia and non-Hodgkin's lymphoma within Seascale among those born there and among those born elsewhere. Also, the levels of any paternal preconceptional radiation associated with each case. RESULTS: A significant excess of leukaemia and non-Hodgkin's lymphoma at ages 0-24 was found in Seascale in those who were born there (ratio of observed to expected cases 8.6 and 20.2 respectively; p < 0.01). This also applied to those not born there (7.2 and 16.5; p < 0.01), a group often regarded as not showing an excess. The estimates were then conservatively recalculated so as to overestimate the risks among those born in Seascale and underestimate them among those born elsewhere. On this basis the six cases in those born in Seascale compare with 0.38 expected (15.8; p < 0.001), of which two were associated with paternal preconceptional life-time levels of 100 mSv or greater and three others with levels of 90-99 mSv. Among those born elsewhere, there were five cases (expected 0.74; ratio 6.7, p < 0.01), of which only one was associated with a high level of such radiation. CONCLUSIONS: Paternal preconceptional radiation cannot be the sole cause of the excess in Seascale since it will not explain the excess among those born outside Seascale. It follows that, unless two causes are to be postulated, any single cause must be a factor other than paternal preconceptional radiation. On this basis, the association found among those born there, if not partly due to chance, may reflect an indirect relation with the true cause. The recent hypothesis about such paternal radiation has originated in a subgroup of the excess cases that have aroused concern.

Adolescent↗
PubMed1993

Paternal preconceptional radiation exposure in the nuclear industry and leukaemia and non-Hodgkin's lymphoma in young people in Scotland.

OBJECTIVE: To determine if a relation exists between paternal exposure to relatively high levels of radiation in the Scottish nuclear industry and the risk of leukaemia and non-Hodgkin's lymphoma is subsequently conceived children. DESIGN: Matched case-control study with three controls for each case. SETTING: The whole of Scotland. SUBJECTS: The fathers of 1024 children with leukaemia and 237 children with non-Hodgkin's lymphoma diagnosed in Scotland below the age of 25 among those born in Scotland since nuclear operations began (in 1958) and the fathers of 3783 randomly chosen controls. The fathers of 80 children with leukaemia and 16 with non-Hodgkin's lymphoma in north Cumbria were also covered since some workers at one Scottish nuclear site live over the border in that area. Details of all fathers were then matched against records of the nuclear industry. MAIN OUTCOME MEASURES: Paternal preconceptional radiation exposures, particularly relatively high levels, both lifetime and in the six and three months before conception. RESULTS: No significant excess was observed in any subgroup and there was no significant trend: fathers of three controls but no cases were exposed to lifetime preconceptional levels of 100 mSv or greater (Fisher's exact p value 0.84). In the six months before conception, fathers of two cases and three controls received 10 mSv or more, odds ratio 2.3 (95% confidence interval 0.31 to 17.24). In the three months before conception the fathers of one case and two controls received 5 mSv or more, odds ratio 1.7 (0.10 to 30.76). The results for leukaemia and non-Hodgkin's lymphoma combined were similar. CONCLUSIONS: No significant excess of leukaemia or of leukaemia and non-Hodgkin's lymphoma was found at any radiation level in any preconceptional period.

Adolescent↗
PubMed1993

Rural population mixing and childhood leukaemia: effects of the North Sea oil industry in Scotland, including the area near Dounreay nuclear site.

OBJECTIVE: To determine if any excess of childhood leukaemia and non-Hodgkin's lymphoma was associated with certain striking examples of population mixing in rural Scotland produced by the North Sea oil industry. DESIGN: Details were traced for over 30,000 workers involved in the construction of the large oil terminals in the Shetland and Orkney islands in northern Scotland or employed offshore. Home addresses of the 17,160 Scottish residents were postcoded, integrated with census data, and then classified as urban or rural. Rural postcode sectors, ranked by proportion of oil workers, were grouped into three categories with similar numbers of children but contrasting densities of oil workers. The incidence of leukaemia and non-Hodgkin's lymphoma was examined in these rural (and also in urban) categories in the periods 1974-8, 1979-83 and 1984-8. SETTING: Scotland. SUBJECTS: Young people below age 25. RESULTS: A significant excess of leukaemia and non-Hodgkin's lymphoma was found in 1979-83 in the group of rural home areas with the largest proportion of oil workers, following closely on large increases in the workforce. The area near the Dounreay nuclear installation, where an excess of leukaemia is already well known, was within the rural high oil category. CONCLUSION: The findings support the infection hypothesis that population mixing can increase the incidence of childhood leukaemia in rural areas. They also suggest that the recent excess in the Dounreay-Thurso area is due to population mixing linked to the oil industry, promoted by certain unusual local demographic factors.

Adolescent↗
PubMed1993

Childhood leukaemia and non-Hodgkins lymphoma in young people living close to nuclear reprocessing sites.

An increased incidence of leukaemia and NHL has been recorded close to Britain's two nuclear reprocessing sites at Sellafield in West Cumbria and Dounreay in Northern Scotland. Two hypotheses have been advanced to explain the excesses - paternal preconceptional irradiation (PPI) and an infective basis promoted by population mixing. Subsequent studies have provided no support for the PPI hypothesis and have also shown that this was derived from the analysis of a sub-group. In contrast, support for the population mixing hypothesis has come from a series of studies of residential and occupational situations. One of these showed that the excess near Dounreay was part of a wider increase in rural areas of Scotland affected by the unusual mixing associated with away-from-home work in the North Sea oil industry, being more marked in areas of relatively high social class. It is probable that the excess in Seascale is due to related demographic factors, this parish being extreme in its high social class, geographic isolation and its proximity to Sellafield, the largest, most changing industrial site in rural Britain.

Adolescent↗
PubMed1992

Malignancy in autoimmune diseases.

Rheumatoid arthritis (RA) represents the autoimmune disease that has been most studied in relation to malignancy. An examination of all published cohort studies has indicated a 9.7-fold increase of non-Hodgkin's lymphoma among RA patients after immunosuppressive therapy, and a 2.5-fold increase in the absence of such treatment. Corresponding data for Sjögren's syndrome point to a similar contrast. These findings are inseparable from the hypothesis of impaired immunosurveillance which implies that malignancy is promoted by defects in the immune system. Studies of individuals treated with immunosuppressive drugs, particularly to prevent graft rejection, have indicated that immunosurveillance operates only against a restricted range of neoplasms. These include non-Hodgkin's lymphoma (NHL), squamous cell skin cancer, Kaposi's sarcoma and cervical carcinoma. Other states of immune impairment including AIDS are also associated with marked increases of NHL. There is a striking correspondence between malignancies for which there is epidemiological or laboratory evidence for a virus aetiology and those that are increased by immune impairment. In this respect the epidemiological evidence accords with experimental work that immunosurveillance primarily operates against neoplasms of viral origin. It is therefore possible that a viral aetiology also underlies the excess of NHL in certain autoimmune disorders, particularly after immunosuppressive therapy.

Autoimmune Diseases↗
PubMed1991

Childhood leukaemia and poliomyelitis in relation to military encampments in England and Wales in the period of national military service, 1950-63.

OBJECTIVE: To determine if any excess of childhood leukaemia was associated with the large and increasing numbers of national military servicemen in 1949 and 1950, particularly in rural districts. This would be a further test of the hypothesis that childhood leukaemia can originate in an infection, the transmission of which is facilitated by an increased number of unaccustomed contacts in the community. DESIGN: Rural and urban districts, aggregated by county, were ranked by proportion of servicemen, and five groups containing similar numbers of children were created. In addition, individual local authority districts were ranked and grouped in tenths. Mortality from childhood leukaemia 1950-3 was examined in these groups. Data on infectious diseases were also examined, as well as data on leukaemia in later periods. SETTING: England and Wales. SUBJECTS: Children aged under 15 years. RESULTS: In 1950-3 but not subsequently a significant excess of leukaemia in children under 15 was found in the fifth of county groupings with the highest proportions of servicemen. This was due mainly to a significant excess in children under 2 years (and especially in those under 1 year) in rural districts. It was confirmed among the tenth of local authority districts with the highest proportion of servicemen. These rural areas showed significantly more notifications of, and deaths from, poliomyelitis among children than the rural average. CONCLUSIONS: The findings support the infection hypothesis. That the excess of leukaemia was greatest in children under 1 year suggests transmission of infection among adults and thence to the fetus. The pattern of spread of poliomyelitis may also have been influenced by the presence of large numbers of servicemen.

England↗
PubMed1991

Contacts between adults as evidence for an infective origin of childhood leukaemia: an explanation for the excess near nuclear establishments in west Berkshire?

The increasing tendency for people to work outside their home community--one of the most striking of modern demographic changes--has relevance to a recent aetiological hypothesis about childhood leukaemia: that a community's immune response to an underlying infection can be disturbed by increases in new social contacts. This was tested in the only 28 former county boroughs in which accurate comparisons of workplace data from the 1971 and 1981 censuses are possible--because their boundaries were left unaltered by the major reorganisation in 1974. After ranking the districts according to extent of commuting increase, a significant trend in leukaemia incidence was found at ages 0-14 (P less than 0.05) and a suggestive one at ages 0-4 (P = 0.055). Among ten similar sized groups of county districts ranked by commuting increase, the only significant increases (P less than 0.001) of leukaemia in 1972-85 at ages 0-4 and 0-14 were in the highest tenth for commuting increase. These excesses persisted after excluding Reading, a major part of an area where an excess of leukaemia has been linked to the nearby nuclear establishments at Aldermaston and Burghfield. This whole area has experienced greater commuting increases than 90% of county districts in England and Wales. The findings are consistent with other evidence supporting the above hypothesis; they also suggest that contacts between adults may influence the incidence of leukaemia in children.

Adolescent↗
PubMed1991

Diet and breast cancer.

The issue of diet as a cause of breast cancer has been dominated by fat. Some have judged this convincing enough to warrant dietary recommendations aimed at prevention. Others find the evidence so far rather weak.

Animals↗
PubMed1990

Evidence from population mixing in British New Towns 1946-85 of an infective basis for childhood leukaemia.

Mortality from leukaemia under age 25 was studied in British New Towns to test the hypothesis that leukaemia represents a rare response to a much commoner (but unrecognised) infection, the transmission of which is facilitated when large numbers of people come together. The density of children was higher in the rural, but lower in the overspill, New Towns than in the areas from which their incomers originated. Residents of the rural New Towns had greater diversity of origin than those of the overspill towns of London and Glasgow. These two factors would encourage a greater rise in the postulated underlying infection in the rural towns, and in these a significant excess of leukaemia at ages 0-4 was found in 1946-65. In both sets of towns there was a significant deficit in other age groups consistent with immunising effects of the relevant infection. There are parallels with feline leukaemia virus infection, in which contrasting leukaemogenic and immunising effects occur in different social settings owing mainly to differences in intensity of viral exposure.

Adolescent↗
PubMed1990

Factors associated with childhood cancer in a national cohort study.

Information on 16,193 infants delivered in Great Britain in one week of April, 1970 was collected by midwives at the birth and during the first 7 days of life. Using multiple sources, 33 children developing cancer by 1980 were identified from this cohort, giving an incidence of 2.04 per 1,000 total births by the age of 10. Comparisons of these 33 children were made with 99 controls, three for each index case, matched on maternal age, parity and social class. Statistically significant associations were initially found with maternal X-rays and smoking during pregnancy, and the use of analgesics such as pethidine during labour, confirming the findings of retrospective case-control studies. Unexpected statistically significant associations were found with delivery of the child outside term, and drug administration in the first week of life. The latter was found in the absence of an association with neonatal abnormalities in the child and relates mostly to the administration of prophylactic drugs such as vitamin K. Logistic regression involving the whole cohort showed independent statistical associations with maternal smoking (OR 2.5), and drugs to the infant (OR 2.6). After adjusting for these factors no other statistically significant associations were found.

Adult↗