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Background and purpose: Caffeine is associated with a lower risk of some neurological diseases, but few prospective studies have investigated caffeine intake and risk of amyotrophic lateral sclerosis (ALS) mortality. We therefore determined associations between coffee, tea and caffeine intake, and risk of ALS mortality. Methods: We conducted pooled analyses of eight international, prospective cohort studies, including 351 565 individuals (120 688 men and 230 877 women). We assessed coffee, tea and caffeine intake using validated food‐frequency questionnaires administered at baseline. We used Cox regression to estimate study‐ and sex‐specific risk ratios and 95% confidence intervals (CI) for ALS mortality, which were then pooled using a random‐effects model. We conducted analyses using cohort‐specific tertiles, absolute common cut‐points and continuous measures of all exposures. Results: During follow‐up, 545 ALS deaths were documented. We did not observe statistically significant associations between coffee, tea or caffeine intake and risk of ALS mortality. The pooled multivariable risk ratio (MVRR) for ≥3 cups per day vs. >0 to <1 cup per day was 1.04 (95% CI, 0.74–1.47) for coffee and 1.17 (95% CI, 0.77–1.79) for tea. The pooled MVRR comparing the highest with the lowest tertile of caffeine intake (mg/day) was 0.99 (95% CI, 0.80–1.23). No statistically significant results were observed when exposures were modeled as tertiles or continuously. Conclusions: Our results do not support associations between coffee, tea or total caffeine intake and risk of ALS mortality. [ABSTRACT FROM AUTHOR]

Background: Although high-dose ionising radiation is associated with increased breast cancer risks, the association with protracted low-dose-rate exposures remains unclear. The US Radiologic Technologist study provides an opportunity to examine the association between low-to-moderate dose radiation and breast cancer incidence and mortality.Methods: One thousand nine hundred and twenty-two self-reported first primary cancers were diagnosed during 1983-2005 among 66 915 female technologists, and 586 breast cancer deaths occurred during 1983-2008 among 83 538 female cohort members. Occupational breast dose estimates were based on work histories, historical data, and, after the mid-1970s, individual film badge measurements. Excess relative risks were estimated using Poisson regression with birth cohort stratification and adjustment for menopause, reproductive history, and other risk factors.Results: Higher doses were associated with increased breast cancer incidence, with an excess relative risk at 100 mGy of 0.07 (95% confidence interval (CI): -0.005 to 0.19). Associations were strongest for technologists born before 1930 (excess relative risk at 100 mGy=0.16; 95% CI: 0.03-0.39) with similar patterns for mortality among technologists born before 1930.Conclusions: Occupational radiation to the breast was positively associated with breast cancer risk. The risk was more pronounced for women born before 1930 who began working before 1950 when mean annual doses (37 mGy) were considerably higher than in later years (1.3 mGy). However, because of the uncertainties and possible systematic errors in the occupational dose estimates before 1960, these findings should be treated with caution. [ABSTRACT FROM AUTHOR]

Objective:To investigate whether the nature of the relationship between body mass index (BMI (kg/m2)) and all-cause mortality is direct, J- or U-shaped, and whether this relationship changes as people age.Design:Prospective nationwide cohort study of US radiologic technologists (USRT).Subjects:Sixty-four thousand seven hundred and thirty-three female and 19 011 male certified radiation technologists.Methods:We prospectively followed participants from the USRT study who completed a mail survey in 1983–1989 through 2000. During an average of 14.7 years of follow-up or 1.23 million person-years, 2278 women and 1495 men died. Using Cox's proportional-hazards regression analyses, we analyzed the relationship between BMI and all-cause mortality by gender and by age group (<55 years; 55 years). We also examined risk in never-smokers after the first 5 years of follow-up to limit bias owing to the confounding effects of smoking and illness-related weight loss on BMI and mortality.Results:Risks were generally J-shaped for both genders and age groups. When we excluded smokers and the first 5 year of follow-up, risks were substantially reduced in those with low BMIs. In never-smoking women under the age of 55 years (excluding the initial 5-year follow-up period), risk rose as BMI increased above 21.0 kg/m2, whereas in older women, risk increased beginning at a higher BMI (25.0 kg/m2). Among younger men who never smoked (excluding the initial 5-year follow-up period), risk began to rise above a BMI of 23.0 kg/m2, whereas in older men, risk did not begin to increase until exceeding a BMI of 30.0 kg/m2.Conclusions:In younger/middle-aged, but not older, women and men, mortality risks appear directly related to BMI. The more complicated relationship between BMI and mortality in older subjects suggests the importance of assessing whether other markers of body composition better explain mortality risk in older adults.International Journal of Obesity (2006) 30, 822–829. doi:10.1038/sj.ijo.0803193; published online 10 January 2006 [ABSTRACT FROM AUTHOR]

Background: There are limited data on risks of haematopoietic malignancies associated with protracted low-to-moderate dose radiation. Aims: To contribute the first incidence risk estimates for haematopoietic malignancies in relation to work history, procedures, practices, and protective measures in a large population of mostly female medical radiation workers. Methods: The investigators followed up 71 894 (77.9% female) US radiologic technologists, first certified during 1926-80, from completion of a baseline questionnaire (1983-89) to return of a second questionnaire (1994-98), diagnosis of a first cancer, death, or 31 August 1998 (731 306 person-years), whichever occurred first. Cox proportional hazards regression was used to compute risks. Results: Relative risks (RR) for leukaemias other than chronic lymphocytic leukaemia (non-CLL, 41 cases) were increased among technologists working five or more years before 1950 (RR = 6.6, 95% CI 1.0 to 41 .9, based on seven cases) or holding patients 50 or more times for x ray examination (RR = 2.6, 95% CI 1.3 to 5.4). Risks of non-CLL leukaemias were not significantly related to the number of years subjects worked in more recent periods, the year or age first worked, the total years worked, specific procedures or equipment used, or personal radiotherapy. Working as a radiologic technologist was not significantly linked with risk of multiple myeloma (28 cases), non-Hodgkin's lymphoma (118 cases), Hodgkin's lymphoma (31 cases), or chronic lymphocytic leukaemia (23 cases). Conclusion: Similar to results for single acute dose and fractionated high dose radiation exposures, there was increased risk for non-CLL leukaemias decades after initial protracted radiation exposure that likely cumulated to low-to-moderate doses. [ABSTRACT FROM AUTHOR]

Objectives: To explore whether mortality from female breast, ovarian, colon, and prostate cancer were negatively associated with exposure to sunlight.Methods: A death certificate based case-control study of mortality was conducted into five cancers: female breast, ovarian, colon, prostate, and non-melanoma skin cancer (as a positive control) to examine associations with residential and occupational exposure to sunlight. Cases were all deaths from these cancers between 1984 and 1995 in 24 states of the United States. Controls, which were age frequency matched to a series of cases, excluded deaths from cancer and certain neurological diseases. Multiple logistic regression was used in a model that included age, sex, race, residential exposure to sunlight (based on region), and socioeconomic status, occupational exposure to sunlight, and physical activity (the last three based on usual occupation).Results: Residential exposure to sunlight was negatively and significantly associated with mortality from female breast, ovarian, prostate, and colon cancer. Only female breast and colon cancer, however, also showed significant negative associations with jobs with the highest occupational exposure to sunlight (odds ratio (OR) 0.82 (95% confidence interval (95% CI) 0.70 to 0.97) for female breast cancer; OR 0.90 (95% CI 0.86 to 0.94) for colon cancer). For both cancers, the negative association with occupational sunlight was greatest in the geographical region of highest exposure to sunlight and was independent of physical activity on the job. Non-melanoma skin cancer, as expected, was positively associated with both residential and occupational sunlight.Conclusions: In this exploratory study, unlike mortality from non-melanoma skin cancer, mortality from female breast cancer and colon cancer were negatively associated with both residential and occupational sunlight. [ABSTRACT FROM AUTHOR]

Objectives: To explore whether mortality from multiple sclerosis is negatively associated with exposure to sunlight.Methods: Two case-control studies based on death certificates were conducted for mortality from multiple sclerosis and non-melanoma skin cancer (as a positive control) to examine associations with residential and occupational exposure to sunlight. Cases were all deaths from multiple sclerosis between 1984 and 1995 in 24 states of the United States. Controls, which were age frequency matched to a series of cases, excluded cancer and certain neurological deaths. The effects of occupational exposure to sunlight were assessed among subjects with usual occupations requiring substantial activity, so as to exclude those whose indoor jobs resulted from disabilities subsequent to the onset of the disease. Multiple logistic regression analyses were applied, with adjustment for age, sex, race, and socioeconomic status.Results: Unlike mortality from skin cancer, mortality from multiple sclerosis was negatively associated with residential exposure to sunlight (odds ratio (OR)=0.53 (multiple sclerosis) and OR=1.24 (skin cancer)). Odds ratios for the highest occupational exposure to sunlight were 0.74 (95% confidence interval (95% CI) 0.61 to 0.89) for mortality from multiple sclerosis, compared with 1.21 (1.09 to 1.34) for mortality from non-melanoma skin cancer. The OR was 0.24 for the combined effect of the highest levels of residential and occupational exposure to sunlight on multiple sclerosis, compared with an OR of 1.38 for skin cancer.Conclusions: In this exploratory study, mortality from multiple sclerosis, unlike mortality from skin cancer, was negatively associated with both residential and occupational exposure to sunlight. [ABSTRACT FROM AUTHOR]

We evaluated the usefulness of a recent measure of drinking water nitrate as a predictor of long-term average nitrate exposure calculated from historic data. Exposure estimates were calculated for 214 study participants who used public water supplies between 1947 and 1980 in Minnesota. Long-term average nitrate was calculated by linking residential histories to historical nitrate data. For recent exposures, we averaged nitrate measurements in 1980, or the next closest year with measurements. The Spearman correlation coefficient for the relationship between the two measures was 0.54 (95% confidence interval [CI] = 0.44-0.63). Agreement was highest among those residing 34 or more years in their town as of 1980 (r[SUBs] = 0.70; 95% CI = 0.55-0.80). These findings suggest that taking into account the study participants' duration of residence may enhance the validity of using a recent measure as an indicator of past exposures. [ABSTRACT FROM AUTHOR]

Our earlier studies have revealed a direct association between global wrist laxity and scaphoid motion. The present study was undertaken to determine what association, if any, there is between laxity and lunate and/or distal carpal row (represented by the hamate) kinematics. Length measurements were obtained from standardized ulnar and radial deviation radiographs of 60 normal volunteers. From these measurements, the relative motion of the lunate and hamate was assessed by derivation of specific flexion and deviation indices. Linear regression analysis was applied to these data and no correlations between global wrist laxity and lunate or hamate motion were observed. We conclude that variability in global wrist laxity is explained only by alterations in scaphoid motion, manifested as variability in periscaphoid ligamentous motion. [ABSTRACT FROM PUBLISHER]

A population-based case-control study was conducted in Washington County, Maryland (United States) to explore the association between incident bladder cancer and exposure to drinking water from chlorinated surface sources. Cancer cases were White residents, enumerated in a 1975 county census and reported to the Washington County Cancer Registry (n = 294) between 1975 and 1992. White controls, frequency matched by age (+/- 5 years) and gender, were selected randomly from the census (n = 2,326). Households receiving municipal water, which generally derived from chlorinated surface waters, were treated as having 'high exposure' and all others, as 'low exposure.' Duration of exposure to type of drinking water was based on length of residence in the census household prior to 1975. Odds ratios (OR) were calculated using logistic regression methods, adjusting for age, gender, tobacco use, and urbanicity. Bladder cancer risk was associated weakly in the general population with duration of exposure to municipal water. The association was limited to those who had smoked cigarettes. In ever-smokers compared with never-smokers with low exposure, the adjusted ORs for bladder cancer risk with increasing exposure were 1.3, 1.4, 1.4, 1.7, 2.2, 2.8, respectively, for 0, 1-10, 11-20, 21-30, 31-40, > 40 years' exposure duration. The ORs in smokers were not diminished after adjusting for smoking history and intensity. [ABSTRACT FROM AUTHOR]

A new surgical treatment for De Quervain’s disease is presented, in which the anatomy and function of the first dorsal compartment is preserved. Our findings in 11 wrists in ten patients revealed complete relief of the pre-operative symptoms in all instances. The advantages of this technique are its ease, its restoration of normal anatomy, and the prevention of tendon prolapse. [ABSTRACT FROM PUBLISHER]

Presents several letters to the editor in reference to articles and topics discussed in previous issues. "The Attorney and the Non-Attorney Arbitrator," which discusses the engineer-arbitrator's style, published in the Fall 1997 issue; Remarks on the policy statement of the U.S. Equal Employment Opportunity Commission regarding mandatory mediation.