Harry M. Schey

Analgesic-Associated Nephropathy and Transitional Cell Carcinoma of the Urinary Tract

Epidemiologic studies from Europe suggest that patients with analgesic-associated nephropathy have an increased risk of developing transitional cell carcinoma of the urinary tract. We did a similar epidemiologic study supporting this association. Six of 115 cases of transitional cell carcinoma diagnosed over 3 years had analgesic-associated nephropathy. The patients were predominantly female, younger, and had renal pelvis tumors instead of bladder tumors (P < 0.002), an mortality rate was higher (P < 0.05). In a historical prospective study, 146 patients with interstitial nephritis diagnosed between 1974 and 1976 were divided into those with and those without analgesic-associated nephropathy. In 4 of 84 patients with analgesic-associated nephropathy transitional cell carcinoma has developed. None of the 98 patients without analgesic associated nephropathy have developed transitional cell carcinoma (P < 0.001). These data strongly incriminate analgesic abuse as a risk factor for the development of transitional cell carcinoma.

The relationship between weight-height indices and the triceps skinfold measure among children age 5 to 12.

This study examines several weight for height indices--Quetelets index W/H2, W/H, and Rohrers index W/H3--for their appropriateness in estimating adiposity among young children. Data were obtained for a sample of 1,668 children age 5-12 residing in Forsyth County, North Carolina. Although W/H2 was found to be the most useful of these indices, the results suggest that no index, including the tricep skinfold measure, can be considered completely satisfactory in estimating adiposity among children.

An approach to the noninvasive periodic assessment of arterial elasticity in the young

The detailed variation of the lumen diameter of common carotid arteries throughout the cardiac cycle was noninvasively measured using a pulse-echo ultrasonic technique in a population of 100 free-living, unrelated, human subjects between the ages of 6 and 25 years. The fractional diameter change (mean +/- SEM) during the cardiac cycle in the 50 male subjects (0.122 +/- 0.004) was found to be significantly (P less than 0.001) greater than the corresponding diameter change in the 50 female subjects (0.106 +/- 0.003). The pressure-strain elastic modulus, Ep, for the carotid arteries was also computed for these subjects by dividing the blood pulse pressure measured in the brachial artery by the fractional diameter change of the carotid. The male elastic modulus (67 +/- 3 kPa) was not significantly (P approximately 0.17) different from the female elastic modulus (62 +/- 2 kPa). Subject age and systolic blood pressure were able to explain approximately one-third of the variability in Ep. Reproductibility studies clearly demonstrated that only a small fraction of the remaining variability could be attributed to experimental technique or intrasubject variability. The results suggest that studies can now be safely performed on young human subjects to assess the effects of a variety of developmental, behavioral, and environmental factors on arterial elasticity. Such results could help to establish an important data base on arterial mechanics which might help in evaluating health promotion recommendations to societies.

Prevalence Rate of Renal Stone Disease in Forsyth County, North Carolina During 1977

A count of all recorded hospitalized cases of Forsyth County, North Carolina residents with a primary discharge diagnosis of renal (kidneyand/or ureteral) stone in 1977 is obtained by age, race and sex, and used in conjunction with the census data to estimate age-adjusted prevalence rates. The over-all prevalence rate is 2.08 per thousand population, which agrees well with results of earlier investigations. For white male subjects the age-adjusted prevalence rate is 3.64 per thousand, for white female subjects 1.44, for non-white male subjects 0.97 and for non-white female subjects 0.34. The white to non-white ratio and the male to female rates are compared with earlier published values. For all groups the prevalence rate increases with age, attaining a maximum in the 40 to 60-year category for whites and somewhat later for non-whites. Beyond age 60 prevalence drops, reaching 0 or near 0 in the 80 to 89-year range. A simple phenomenological model is suggested to explain the observed race and sex differences in the prevalence rates.

Weight-for-height indices as measures of adiposity in children

This study examines the weight-for-height index q = w/h lambda where the parameter lambda is chosen to maximize the correlation of q with triceps skinfold thickness, and thus provide an indirect measure of adiposity. Using a sample of 1668 children ages 5-12 years, we estimate lambda by an iterative procedure in each age/sex category. We find that lambda does not vary simply across the age/sex categories, and that the correlation of q and skinfold thickness is never more than marginally greater than that of the Quetelet index w/h2. We indicate that almost identical properties will be evidenced by the more general two-parameter index w alpha/h beta. Our conclusion is that there is no weight-for-height index generally useful as an indirect measure of adiposity in children.

Standardized method for recording blood pressure in anaesthetized Macaca fascicularis

Blood pressures obtained from anaesthetized non-human primates by this indirect, noninvasive method correlate well with direct blood pressure measurements on anaesthetized animals (systolic R = 0·959, diastolic R = 0·946) and on conscious subjects (R = 0·84). Between- and within-animal variances of indirectly-obtained blood pressure recordings in anaesthetized animals were relatively small. The systolic blood pressure standard deviation was 11·566 among animals and 2·233 within animals, diastolic 7·618 and 0·475 respectively.

A Comparison of Height, Weight, and Triceps Skinfold Thickness of Children Ages 5-12 in Michigan (1978), Forsyth County North Carolina (1978), and HANES I (1971-1974)

Height, weight, and triceps skinfold measurements were made on 1,668 Forsyth County, North Carolina students ages 5-12 during 1978. These data were compared to a representative sample of Michigan children taken during the same year and to their United States counterparts in HANES I (1971-74). The North Carolina children more closely resembled their US counterparts than did the Michigan group, casting doubt on the secular trend toward heavier children suggested by the Michigan researchers. (Am J Public Health 1982; 72:730-733.)

A study of leukemia clustering in Albemarle, North Carolina, 1968–1978

Clustering of leukemia in an endemic area was investigated by an analysis of the way in which cases were distributed in space, in time, and in space and time together. The results were negative, suggesting that leukemia in the target area did not result from a contagious virus or from any other causative agent which would give rise to clustering. Rather than seeking a contagious viral basis for this disease, it would be more useful to conduct a retrospective case‐control study that might uncover etiologic agents not associated with clustering.

Objective measurement of physical activity in Macaca fascicularis

The mean and standard deviation over 24 h for 3 groups of animals - active, intermediate and inactive - in physical activity units were 10948 ± 3360, 2611 ± 1973 and 484 ± 316 respectively. The differences were significant (P = 0·004), demonstrating the ability of the method to distinguish between groups that can be visibly differentiated. The small within-animal physical activity standard deviation (18·85 PAU) obtained in another group, suggests that it also yields reliable physical activity measurements for non-human primates. The monitoring device used can discriminate between individual nonhuman primate physical activity levels in a free-living environment and does not alter daily behaviour. This makes possible the study of the relationship between physical activity and atherosclerosis in nonhuman primates.