Diet and premenopausal bilateral breast cancer: A case-control study

We investigated associations between diet and premenopausal bilateral breast cancer in a familial matched case-control study. We studied 140 cases from population-based registries in Los Angeles County (California) and Connecticut, and from the major hospitals in the southern parts of the Province of Quebec. Unaffected sisters of the cases served as matched controls (222 total). Dietary intake were assessed with a food frequency questionnaire. Total fat, monounsaturated fat, polyunsaturated fat, oleic acid, and linoleic acid intake was inversely associated with premenopausal bilateral breast cancer risk. Consumption of carbohydrates (and sweetened beverages) was associated with an increased risk. We observed no associations for dietary fiber, antioxidants, or major food groupings, but we did observe inverse associations for intake of low fat dairy products and tofu. These findings suggest that monounsaturated and polyunsaturated fats, as well as soy foods, might reduce the risk of premenopausal bilateral breast cancer.     

Possible heterogeneity in the segregation pattern of breast cancer in families with bilateral breast cancer

We investigated the segregation pattern of breast cancer in families with bilateral breast cancer, classifying families with respect to menopausal status (premenopausal versus postmenopausal) and the interval between diagnosis of the two primary tumors in the probands. Probands were "synchronous" if both primaries were diagnosed within 1 year; "asynchronous" if the interval was at least 2 years. Results for four complex segregation analyses are here presented; the findings support heterogeneity in the transmission of breast cancer. In the asynchronous premenopausal-cases-only analysis, a dominant Mendelian gene can explain the breast cancer pattern. A recessive gene is sufficient to describe the breast cancer distribution in the synchronous premenopausal-cases-only analysis. The synchronous all-cases and the asynchronous all-cases analyses add postmenopausal cases of breast cancer to the premenopausal ones, considering any case to be affected. In the asynchronous all-cases analysis, neither the single-locus model nor the mixed model (that is, a major locus plus other factors, genetic and/or cultural) without generation differences in heritability can be rejected by the unrestricted mixed model with generation differences in heritability. For the synchronous all-cases analysis, a mixed model with generation differences in heritability is necessary to explain the breast cancer transmission. Potential sources of error and possible interpretations are discussed.     

Home Versus Clinic Blood Pressure Measurements

To evaluate the cost effectiveness of home versus clinic blood pressure 11 patients with mild untreated hypertension were instructed in self-measurement of blood pressure with mercury manometers. The lower total cost of using home readings as well as problems of bias and blinding are discussed. Home blood pressure is a promising technique for clinical and epidemiologic research.     

Computer simulation of Rocky Mountain spotted fever transmission by the American dog tick (Acari: Ixodidae)

A computer model was developed for simulation of the transmission of Rickettsia rickettsii, the causative agent of Rocky Mountain spotted fever (RMSF), by the American dog tick, Dermacentor variabilis (Say). The model of RMSF was combined with a model for population dynamics of the American dog tick and included simulation of infection and transmission of rickettsiae between ticks and host mammals and transmission of RMSF to humans. The model simulated the effects of biotic and environmental variables such as weather, host density, habitat, transovarial transmission, fecundity of infected ticks, and infectivity level of ticks and mammals. Some parameters in the model were fitted by iterative simulations to produce realistic rates of R. rickettsii infection in adult ticks and small and medium-sized mammal hosts. Parameters also were fitted to yield the historical average number of RMSF cases for Virginia. Comparisons of the simulated and actual number of cases for nine other states indicated a reasonable level of validity for the model. A theoretical tick density threshold of 252 unfed adult ticks/ha for transmission of RMSF was determined from a relationship between rate of transmission to humans and density of ticks. The transmission threshold can be used for additional modeling efforts to study the effects of management technologies on tick densities and RMSF human cases. The model can serve as a framework for modeling other tick-borne diseases such as Lyme disease, babesiosis, and heartwater.     

A reappraisal of time trends in ulcer disease: factors related to changes in ulcer hospitalization and mortality rates.

There has been a dramatic decline in reported hospitalization and mortality rates for peptic ulcer disease in the past two decades. Data from the National Center for Health Statistics and from the Commission on Professional and Hospital Activities were examined to determine the cause(s) for this decline. Gastric and duodenal ulcer mortality rates decreased by 58 per cent and 68 per cent, respectively, from 1962 to 1978; changes in criteria for selecting the underlying cause of death might account for some of this apparent decrease. Hospitalization rates for duodenal ulcers decreased nearly 50 per cent from 1970 to 1978, but hospitalizations for gastric ulcers did not decrease. During this same time period, hospitalizations for peptic ulcers as one of the "all listed" causes remained stable, and hospitalizations for a closely related diagnosis, gastritis/duodenitis, increased. Changes in coding practices, hospitalization criteria, and diagnostic procedures appear to have contributed to the decline in reported hospitalization and mortality rates for peptic ulcer disease.     

Prediction of early (4-week) mortality in acute myeloid leukemia with intensive chemotherapy

The progress with intensive chemotherapy and supportive care measures has improved survival in patients with newly diagnosed acute myeloid leukemia (AML). Given the recent development of effective low intensity therapies, an optimal decision on the therapy intensity may improve survival through the avoidance of early mortality. We reviewed the outcome of 3728 patients with newly diagnosed AML who received intensive chemotherapy between August 1980 and May 2020. Intensive chemotherapy was defined as a cumulative cytarabine dose ≥ 700 mg/m² during induction therapy. We divided the whole cohort into a training and validation group at a 3:1 ratio. The population was divided into a training (2790 patients) and a validation cohort (938 patients). The median age was 55 years (range, 15-99). Among them, 442 patients (12%) had core-binding factor AML. Binary logistic regression identified older age, worse performance status, hyperbilirubinemia, elevated creatinine, hyperuricemia, cytogenetic abnormalities other than CBF and -Y, and pneumonia as adverse prognostic factors for an early 4-week mortality. This risk classification for early mortality was verified in the validation cohort of patients. In the validation cohort of more recently treated patients from 2000 to 2017, the 4-week mortality rates with intensive chemotherapy were 2%, 14%, and 50% in the low-, high-, and very high-risk group, respectively. The mortality rates with low intensity therapies were 3%, 9%, and 20%, respectively. The risk classification guides treatment intensity by the assessment of age, frailty, organ dysfunction, cytogenetic abnormality, and infection to avoid early mortality.