Search PubMed⌕ Search

Biomedical subjects

W F Forbes

Publications and source records attributed to W F Forbes.

At least 55 records · Page 3Linked to original sources
PubMed1976

A mathematical model of aging processes. IV. A multivariate analysis of blood pressure in a Montreal and a Utah population.

Two populations, one Montreal- and one Utah-based, were studied with respect to heart disease risk factors on a cross-sectional basis. The Utah population afforded consistently lower mean blood pressures than the Montreal population, although there was not evidence that the Utah population was less obese, or had a lower pulse rate. Also, in the Utah population, it was found that the proportion of persons with a family history of heart disease did not differ significantly in the hyper- and normo-tensive groups. Fourteen parameters were investigated in the Montreal population, and the analyses indicated that, when other variables are controlled, age, pulse rate, some measure of serum lipid levels, and a family history of heart disease generally assist in the discrimination between the hyper- and normo-tensive groups, but the obesity measurement did not. In that sense, obesity, on its own, may not be considered a risk factor for hypertension.

Aging↗
PubMed1976

Concerning the estimation of biological age.

The conditions which must be satisfied by an index of biological age are discussed, and a high correlation with chronological age is shown to be neither a necessary nor a sufficient condition to be satisfied by any such index.

Adult↗
PubMed1976

Studies on the nicotine exposure of individual smokers. I. Changes in mouth-level exposure to nicotine on switching to lower nicotine cigarettes.

Twenty-four subjects smoked two brands of filter-tipped cigarettes delivering different amounts of nicotine, on the following 4-week schedule: 1. Smoking their usual brand for 1 week. 2. Smoking another brand similar in size, but delivering less nicotine, for 2 weeks. 3. Reverting to their usual brand for 1 week. The amount of nicotine entering the mouth, defined as the mouth-level exposure, was estimated from a determination of the amount of nicotine trapped in the filter of each cigarette smoked. The results indicate a substantial variation in mouth-level exposure for the subjects studied, even among smokers of cigarettes that deliver similar amounts of nicotine when smoked on a machine under standard conditions. For the majority of subjects, however, changing to a lower nicotine cigarette reduced the total daily mouth-level exposure to nicotine and, therefore, presumably the total tar intake.

Adult↗
PubMed1975

The role of carbon monoxide in cigarette smoking. I. Carbon monoxide yield from cigarettes.

The carbon monoxide deliveries of 20 major Canadian brands of cigarettes, determined by gas chromatography and using standard smoking conditions, were estimated and found to vary by a factor of about two. The CO yields were found to increase with puff volume and tobacco moisture, decrease with increased paper porosity, but remain essentially constant with puff duration. The data suggest that reduced CO deliveries can be achieved by increasing the cigarette paper porosity. Combustion temperature presumably also influences CO deliveries, but the relative role ascribed to dilution and combustion is not clear. It may be concluded that smokers can lower their CO exposure by reducing their puff volume, smoking cigarettes manufactured from high porosity paper, by taking fewer puffs, and decreasing their tendency to inhale. Since CO and tar deliveries are correlated, these measures would also tend to decrease a smoker's exposure to tar.

Carbon Monoxide↗
PubMed1975

Studies of mortality and morbidity data. II. Mortality from all causes in Ontario Counties during 1964-1968.

Age-adjusted mortality rates, for all causes of death, are tabulated for all ages by sex for the 55 Ontario counties and districts. The rates are based on all deaths of Ontario residents during 1964-1968 and 1966 census populations. The consistent trends in rates, both for the two sexes and for various 10- and 20-year age groups, indicate that there is a region of about eight adjoining counties, across the center of the province, which has abnormally high mortality, and two regions to the east and west of York, each consisting of three adjoining counties which have abnormally low mortality. The relevance of these findings to aging studies is indicated, and possible further investigations of them are discussed.

Adult↗
PubMed1975

A mathematical model of aging processes. III. Comments on the relative importance of serum cholesterol and blood pressure levels on mortality.

The distributions of serum cholesterol, blood pressure, and their values added together, were examined on a cross-sectional basis for a Montreal population. The results showed that all three distributions seem to be represented better by a log normal than by a normal distribution; but in each case, there was no pronounced increase in the skew with age. The distribution of the systolic blood pressure values exhibited an increasing variance with age, whereas the distribution of the serum cholesterol values remained approximately similar with age. The distribution of the two parameters added together also did not alter significantly with age. These results are consistent with the assumption that, if the serum cholesterol value of an individual changes, the individual will be placed at a substantially greater risk than if changes occur for blood pressure levels. Subpopulations of particular concern, with respect to changes in serum cholesterol levels, are those which undergo weight changes and those which smoke cigarettes.

Adult↗
PubMed1975

Autopsy data and their total evaluation.

The role of the autopsy is discussed in the study of the etiology of the current major causes of death (cardiovascular and neoplastic diseases) in developed countries. Evidence is accumulating for the importance of environmental factors in the etiology of these diseases. The study of regional differences in occurrence is described as a method of identifying specific factors. Maps are shown of mortality rates for all causes of death in Ontario counties for males aged 65-74 and 95+ during 1964-68. Some of the difficulties in obtaining data in this form, and in their analysis, are indicated. Regional mortality patterns can be interpreted by the use of associations with available regional socioeconomic measures, or by the use of regional data on trace-metal levels in autopsy samples of human lung, rib, vertebra, kidney and liver. The methodology and the difficulties involved in the determination of trace-metal levels in these tissues are discussed, as is the possible relevance of these levels to the study of degenerative diseases. All these considerations emphasize the valuable contributions of autopsy studies.

Accidents↗
PubMed1972

Smoking and health.

Explore the source record for details and available documents.

Coronary Disease↗