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B F Polk

Publications and source records attributed to B F Polk.

115 records · Page 7Linked to original sources

An evaluation of the Vita-Stat automatic blood pressure measuring device.

Four Vita-Stat (VS) automatic, coin-operated, blood pressure measuring devices were evaluated for accuracy and precision. Under field conditions, 342 adults had two blood pressure measurements with both the VS device and with the Random-Zero (RZ) device. Two of the VS machines gave significantly higher systolic (SBP) and diastolic blood pressure (DBP) values, compared to the RZ values. The mean difference between these two units and the RZ device were clinically important (14.0 and 6.9 mm Hg SBP; 7.5 and 6.8 mm Hg DBP), and resulted in the misclassification of 23% of normotensives as hypertensives. We observed a significant order effect on SBP with the VS device, with a mean decrement of 4.9 mm Hg between the first and second SBP values, compared to 0.6 mm Hg with the RZ device. Even after adjusting for this bias, all four VS devices gave significantly more variable SBP readings than the RZ unit; two of the four also gave more variable DBP values. These data suggest that the VS device is neither accurate nor precise enough at the present time to be recommended for widespread use. These findings also raise questions concerning the monitoring of performance of this and similar devices in the field.

Adult↗

Comparative immunogenicity of plasma and recombinant hepatitis B virus vaccines in homosexual men.

A randomized, double-blind clinical trial of plasma-derived and DNA recombinant hepatitis B virus vaccines was conducted in 186 homosexual men. Nine months after the immunization series (three doses) began, the seroconversion rate in the plasma vaccine group was 88% (68/77); this was significantly higher than the 74% (60/81) response rate of the recombinant vaccine group. Men positive for antibody to the human immunodeficiency virus (HIV) had a considerably higher nonresponse rate to either vaccine than expected in non-HIV-infected homosexual men. The odds ratios of nonresponse to hepatitis B virus vaccine for HIV-seropositive vs HIV-seronegative subjects were 12.0 (95% confidence interval, 1.7 to 89.3) and 13.6 (95% confidence interval, 2.3 to 148.3) for the plasma and DNA recombinant vaccines, respectively.

Adult↗

Absence of antibodies to HTLV-III in health workers after hepatitis B vaccination.

A proportion of the plasma for the triply inactivated, plasma-derived hepatitis B vaccine produced in the United States is obtained from homosexual men. Because homosexual men are a high-risk group for the acquired immunodeficiency syndrome (AIDS), concern has emerged that the vaccine could harbor the AIDS agent. To evaluate this risk, we tested 15-month postvaccination serum samples for antibodies to human T-cell lymphotropic virus type III in 100 health care workers who had received inactivated hepatitis B vaccine lots made from plasma collected between 1977 and 1979 and 100 who had received placebo injections. None of the 200 health workers had serological evidence of human T-cell lymphotropic virus type III infection. These serological findings lend additional support to earlier epidemiologic and immunologic observations suggesting that hepatitis B vaccine does not transmit infection with an AIDS virus.

Antibodies, Viral↗

Effects of labeling and treatment of hypertension on perceived health.

The effects of labeling a person as hypertensive have important implications for hypertension screening. The Hypertension Detection and Follow-up Program (HDFP) provides an opportunity to examine the effects of labeling, treatment, and study assignment on a large group of hypertensives (n = 10,070). Their answers to questions regarding perceived health and general well-being asked at baseline and again one year later were analyzed. There was no significant change in the perceived health status of persons who were unaware of their hypertension at baseline and remained untreated at one year (labeling alone). The effect of labeling plus treatment was associated with a significant decrease in perceived health. The effect of antihypertensive drug therapy on perceived health status was examined in persons who were aware of their hypertension but not on treatment at baseline, and on treatment at one year. The stepped care group (SC) had a significant improvement in their perceived health and a significant decrease in the amount of time spent worrying about their health. The referred care group (RC) had no change. Program assignment effects were studied in individuals aware of their hypertension and on treatment both at baseline and one year later. Both the SC and RC groups had a significant improvement in their perceptions of their health status. The SC group had a significant decrease in time spent worrying about their health, while the RC group showed no change. These reassuring results fail to support the suggestion that labeling persons as hypertensive is necessarily followed by negative psychological consequences.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗