Biomedical subjects

T Hammerstrom

Publications and source records attributed to T Hammerstrom.

4 recordsLinked to original sources

PubMed1996

Sedative-hypnotic drugs and the risk of hip fracture.

A retrospective cohort study was conducted in individuals 65 years of age and older using Medicaid-reimbursed claims to assess the risk of hip fracture in users of two sedative-hypnotic drugs, triazolam and temazepam. Using the triazolam cohort as the referent group, the rate ratio was 0.92 (95% confidence interval, 0.72 to 1.17) for hip fracture with temazepam. Stratifying by age, sex, race, residence, time enrolled in Medicaid, prescription number, combinations of these, and several other potential confounding variables did not materially change the results. Compared with the short-acting benzodiazepine hypnotic temazepam, use of triazolam, an ultra-short-acting benzodiazepine hypnotic, did not decrease the risk of hip fracture. This study did not determine that either drug, compared with no use in an insomniac control group, increases the risk of hip fracture. However, because sedative-hypnotic drugs have been found in other studies to increase the risk of falling and hip fracture, they should be used with caution, especially in the elderly.

Accidental Falls↗

PubMed1995

Dissolution test acceptance sampling plans.

The U.S. Pharmacopeia (USP) general monograph provides a standard for dissolution compliance with the requirements as stated in the individual USP monograph for a tablet or capsule dosage form. The acceptance rules recommended by USP have important roles in the quality control process. The USP rules and their modifications are often used as an industrial lot release sampling plan, where a lot is accepted when the tablets or capsules sampled are accepted as proof of compliance with the requirement. In this paper, the operating characteristics of the USP acceptance rules are reviewed and compared to a selected modification. The operating characteristics curves show that the USP acceptance rules are sensitive to the true mean dissolution and do not reject a lot or batch that has a large percentage of tablets that dissolve with less than the dissolution specification.

Capsules↗

PubMed1992

Temporal patterns in air pollution and hospital admissions.

A 6-year data set of daily counts of admissions to 79 acute care hospitals in Southern Ontario was analyzed in relation to concurrent measurements of air pollution and weather pooled over the same regions, using progressively more sophisticated statistical techniques. The diagnoses studied included a group of respiratory causes and two control diagnoses: accidents and gastrointestinal causes. The 6-year period (1979-1985) was subdivided into six 2-month "seasons" and the area of study was divided into three subregions. Bivariate correlations were found to be significant more often than expected due to chance for all three admissions variables, but accounting for the temporal variation within the 60-day seasons greatly reduced the significance of the control diagnoses. Twenty-four-hour averages for air quality were found to yield more significant associations than peak hourly concentrations. July-August was the only period not having important within-season temporal trends and also had the lowest daily counts for respiratory admissions. Based on a model which accounted for serial correlation, SO2, ozone, and sulfate aerosol were found to be significant predictors of respiratory admissions during July-August. Using cumulative lags increased the magnitude of the estimated response to about 20% of summer respiratory admissions, but no consistent relationships were found which could identify the "responsible" pollutant(s) with certainty. Average pollutant concentrations were generally within U.S. ambient standards.

Accidents↗

PubMed1989

Health risks of short-term SO2 exposure to exercising asthmatics.

A method is described for quantifying health risks to asthmatics briefly exposed to elevated levels of SO2. By combining symptomological and physiological measurements, we have developed a dose-response surface that relates both severity and incidence of response to ambient air quality levels. The complete model to assess potentially avoidable risks includes power plant emission data; ambient SO2 background levels; demographic and activity patterns of asthmatics, the identified population at risk; and the dose-response surface. The estimated annual risk to persons experiencing an SO2-induced response due to a nearby power plant is quite small (response rates under 3 percent). Uncertainties due to modeling errors, variations in activity patterns, demographics and physiological response are discussed.

Air Pollutants, Occupational↗