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Biomedical subjects

B F Polk

Publications and source records attributed to B F Polk.

At least 91 records · Page 5Linked to original sources
PubMed1984

Hypertension detection and follow-up program study of serum retinol, retinol-binding protein, total carotenoids, and cancer risk: a summary.

In a recently reported study by us, no significant associations were found between retinol, retinol-binding protein (RBP), and total carotenoid levels in prediagnositic serum and the incidence of cancer at all sites combined. Inasmuch as other investigators, in addition to us, have not been able to confirm the two original reports of an inverse association between serum retinol and overall cancer incidence, the relationship, if it exists at all, is probably complex and limited to certain population subgroups. Such subgroups may be defined by extreme values of serum retinol, certain levels of other nutrients, or specific types of cancer. In the present study an inverse association was observed between serum retinol levels and cancer among subjects with low serum selenium levels and for subjects with gastrointestinal cancer. In addition, the risk of cancer was elevated for those individuals with the combination of low serum retinol and high RBP. However, since significant associations will arise by chance alone when many subgroups are examined, these findings are difficult to interpret. Additional studies will be needed to determine whether they are reproducible or are simply the results of chance.

Carotenoids↗
PubMed1983

Prediagnostic serum selenium and risk of cancer.

Selenium levels in serum samples collected in 1973 from 111 subjects in whom cancer developed during the subsequent 5 years were compared with those in serum samples from 210 cancer-free subjects matched for age, race, sex, and smoking history. The mean selenium level of cases (0.129 +/- SEM 0.002 micrograms/ml) was significantly lower than that of controls (0.136 +/- 0.002 micrograms/ml). The risk of cancer for subjects in the lowest quintile of serum selenium was twice that of subjects in the highest. Multivariate adjustment for geographical area and serum levels of lipids, vitamins A and E, and carotene, did not alter this relation. The association between low selenium level and cancer was strongest for gastrointestinal and prostatic cancers. Serum levels of vitamins A and E compounded the effect of low selenium; relative risks for the lowest tertile of selenium were 2.4 and 3.9 in the lowest tertiles of vitamins E and A, respectively.

Adult↗
PubMed1983

Reduction of mortality associated with nosocomial urinary tract infection.

A randomised controlled trial was conducted to assess whether bladder catheters with preconnected sealed junctions were associated with a lower risk of urinary-tract infection than were catheters without such junctions, and to determine whether prevention of catheter-associated infection would be accompanied by a reduction of mortality. Among those not taking systemic antibiotics, patients assigned sealed junction catheters had fewer infections and deaths. Before they received antibiotics, the risk of infection among those assigned unsealed catheters was 2.7 times that of patients assigned sealed catheters (95% confidence interval=1.3-5 . 4, p=0 . 007). Among the 220 patients who received no antibiotics, 14% (15/108) of those assigned unsealed catheters and 4% (4/112) of those assigned sealed catheters died. Stratification by important risk factors for mortality yielded an adjusted risk ratio for death of 3.4 (95% CI=1.1-10.7, p=0.03). Among patients who received systemic antibiotic the use of sealed catheters did not affect infection rates (RR=0.9, 95% CI=0.5-1.5, p=0.68) or deaths (RR=1.2, 95% CI=0.6-2.2, p=0.62). These data indicate how the rates of infection and mortality can be reduced in hospital. Since the degree of reduction in mortality corresponded with the degree of reduction of infection, measures to prevent catheter-associated nosocomial urinary tract infection should be implemented.

Anti-Bacterial Agents↗
PubMed1983

Benefit-cost analysis of antimicrobial prophylaxis in abdominal and vaginal hysterectomy.

We performed a benefit-cost analysis of antimicrobial prophylaxis for hysterectomy using data from a randomized, placebo-controlled clinical trial of the efficacy of three doses of cefazolin sodium. The excess cost per patient with either operative site or urinary tract infection, or febrile morbidity diagnosed during hospitalization, was +1,777 for vaginal and +716 for abdominal hysterectomy. In patients undergoing vaginal hysterectomy, prophylactic cefazolin reduced in-hospital infectious morbidity from 52% to 23% (preventive fraction, 56%), resulting in an average net benefit of +492 per patient. In abdominal hysterectomy, cefazolin decreased in-hospital morbidity from 43% to 25% (preventive fraction, 42%), resulting in an average net savings of +102 per patient. These benefits would be eroded by use of newer, more expensive cephalosporins unless they were considerably more effective than cefazolin. The benefits also would be diminished by inappropriate prolongation of the duration of prophylaxis.

Cefazolin↗
PubMed1983

Malformations in infants of diabetic mothers: problems in study design.

Infants of diabetic mothers have a two- to threefold increased risk of having congenital malformations. Primary prevention of these malformations may be possible if the teratogenic mechanisms in diabetes can be identified. The Diabetes in Early Pregnancy Study (DIEP) addresses the questions of high malformation rates and fetal losses using an innovative study design. Women are recruited prior to pregnancy, monitored to ensure prompt diagnosis of pregnancy, and followed carefully for diabetic problems or fetal losses. To date, 450 diabetic and 550 normal control prepregnant women have been recruited. A basal body temperature monitoring system has been successful in identifying pregnant women within 21 days of conception. Before initiating such a study, problems of feasibility, study design, and possible bias had to be solved. This report summarizes our experience in designing and conducting a prospective pregnancy study. The DIEP demonstrates that a truly prospective pregnancy study is feasible.

Congenital Abnormalities↗
PubMed1983

Predictive values of routine blood pressure measurements in screening for hypertension.

There presently is no consensus regarding criteria for hypertension screening or case finding. Blood pressure variability results in differential ascertainment, depending upon the number of screening visits, the number of measurements per visit, and the method used in reducing the data obtained to an underlying measure of blood pressure status. To develop screening rules, the authors have computed the predictive values of blood pressure measurements for particular age-, race-, and sex-specific groups. Predictive value computations require estimates of between- and within-visit variability and of prevalence. Estimates of variability were calculated from data obtained at a worksite or a community blood pressure program from 991 persons, aged 30-69 years and not currently on antihypertensive medications, who were screened over two to five visits, one week apart. Estimates of prevalence were obtained from the screening of 158,955 adults by the Hypertension Detection and Follow-Up Program. Predictive values are presented for particular age-, race-, and sex-specific groups over a wide range of diastolic blood pressures, and are used to identify appropriate screening rules that minimize misclassification with the fewest possible blood pressure measurements. The results of a questionnaire sent to 30 hypertension experts indicated that the median acceptable predictive values for making screening decisions were 80% for predictive value positive and 77.5% for predictive value negative. When these criteria were adopted, 81%, 90%, and 93% of the subgroup of 901 persons with at least three visits from the above screened population were identified as having or not having true diastolic blood pressure greater than or equal to 90 mmHg after one, two, and three visits, respectively. The status of the remaining 7% remained uncertain after three visits.

Adult↗
PubMed1983

Hepatitis B: a controllable disease.

Major advances have been made in understanding the epidemiology and biology of the hepatitis B virus. Two particular developments--hepatitis B immune globulin and a new hepatitis B virus vaccine--are of special interest to obstetricians, gynecologists, and others who provide health care to women. The appropriate use of hepatitis B immune globulin and hepatitis vaccine can prevent hepatitis B virus infections.

Female↗
PubMed1982

Risk factors for infection at the operative site after abdominal or vaginal hysterectomy.

We studied risk factors for postoperative infections at the operative site after hysterectomies. Data were collected prospectively on all women undergoing vaginal hysterectomies (323 patients) or abdominal hysterectomies (1125 patients) at the Boston Hospital for Women between February 1976 and April 1978. Logistic-regression analysis indicated that factors significantly associated (P less than 0.05) with a higher risk of infection at the operative site were increased duration of operation, lack of antibiotic prophylaxis, younger age, being a clinic patient, and an abdominal approach. After these variables were accounted for, the variables of obesity, preoperative functional and anatomical diagnoses, postoperative anatomical and pathological diagnoses, estimated blood loss, menopausal status, and operation by a specific surgeon did not add predictive power. An increasing duration of operation was associated with a decreasing effect of antibiotic prophylaxis, the preventive fraction of which diminished from 80 per cent at one hour to an unmeasurable effect at 3.3 hours.

Adult↗
PubMed1982

Mortality associated with nosocomial urinary-tract infection.

In a prospective study, 131 of 1458 patients acquired 136 urinary-tract infections (defined as greater than 10(5) colony-forming units per milliliter) during 1474 indwelling bladder catheterizations. Seventy-six patients (25 infected and 51 noninfected) died during hospitalization; death rates were 19 per cent in infected patients and 4 per cent in noninfected patients. Multiple logistic regression analysis demonstrated that seven of 21 prospectively monitored variables were associated with mortality among the catheterized patients. The adjusted odds ratio for mortality between those who acquired infection and those who did not was 2.8 (95 per cent confidence limits, 1.5 to 5.1). The acquisition of infection as not associated with the severity of underlying disease; among patients who died, infections occurred in 38 per cent of those classified as having nonfatal underlying disease (15 of 39) and in 27 per cent of those classified as having fatal disease (10 of 37). Twelve deaths may have been caused by acquired urinary-tract infections. Two patients had urinary-tract pathogens in premortem blood cultures. Another 10 died with clinical pictures compatible with serious infection, but no diagnostic cultures were performed. We conclude that the acquisition of urinary-tract infection during indwelling bladder catheterization is associated with nearly a threefold increase in mortality among hospitalized patients, but the reason for this association is not yet clear.

Catheters, Indwelling↗
PubMed1982

Randomized clinical trial of perioperative cefoxitin in preventing maternal infection after primary cesarean section.

To determine the efficacy of perioperative cefoxitin in preventing infections after primary cesarean section, a randomized placebo-controlled, double-blind clinical trial was performed. Among 266 participants, those who received three perioperative 2 gm doses of cefoxitin (138) had significantly fewer serious infections (19.5% vs. 4.3%), fewer urinary tract infections (10.7% vs. 4.4%), less standard febrile morbidity (9.4% vs. 3.6%), and fewer courses of antibiotics postoperatively (23.4% vs. 11.6%). There was no reduction in the length of hospitalization. Use of perioperative cefoxitin umbilical cord is clamped are safe and efficacious in preventing infection after primary cesarean section.

Cefoxitin↗
PubMed1982

A controlled comparison of joint reactions among women receiving one of two rubella vaccines.

While transient rheumatic side-effects are not uncommon in women receiving any of the attenuated rubella virus vaccines yet developed, few comparative data are available on the only rubella vaccine currently available in the United States - the RA 27/3 vaccine. In this study, the frequency and severity of joint reactions were compared among seronegative women receiving HPV77DE5 vaccine (n = 59) or RA 27/3 vaccine (n = 53), and in seropositive vaccinees receiving either vaccine (n = 60). The proportions of vaccinees developing arthralgia/arthritis were similar (29 per cent and 26 per cent, respectively) in the seronegative groups, and were significantly higher than in the seropositive control group (3%). The onset of symptoms was earlier and their duration was briefer in those receiving RA 27/3 vaccine compared to the HPV77DE5 vaccine recipients. No chronic or recurrent symptoms were observed. These data, along with previous studies, suggest that while transient rheumatic reactions following rubella vaccination are not uncommon, they are not associated with serious disability and should not interfere with ongoing immunization programs.

Adult↗
PubMed1981

Perinatal echovirus infection: risk of transmission during a community outbreak.

During a community outbreak of enterovirus infection, seven of 194 pregnant women (3.6 per cent) were found to be excreting a prime strain of echovirus 11 at term. Each of the seven women possessed serum neutralizing echovirus 11 antibody in titers ranging from 1:20 to 1:320, and the cord serum of their seven infants had antibody in titers of 1:10 to 1:640. None of these seven infants became ill, but four were shedding virus from the respiratory or gastrointestinal tract by three days of age. In a previous study, four infants who died of generalized infection due to the same strain of echovirus 11 had no detectable antibody in cord serum. None of the infants of virus-negative mothers became infected, according to cultures at hospital discharge (151 infants) or at two weeks of age (135 infants). We conclude that passive transplacental acquisition of antibody prevents severe, systemic echovirus disease but does not prevent mucosal infection in the perinatally infected infant.

Antibodies, Viral↗
PubMed1980

An outbreak of rubella among hospital personnel.

An outbreak of 47 cases of rubella occurred among hospital personnel in a large medical-surgical hospital. As a result, one pregnancy was terminated and 475 employee workdays were lost. Epidemiologic investigation of the outbreak suggested a common source; a dietary worker was identified as the probable index case. Serum samples of 12 per cent of women employees were negative for rubella antibody at the time of the outbreak. Neither a history of rubella nor a history of immunization with rubella vaccine was reliable in the prediction of the presence or absence of immunity. Two thirds of all hospital personnel were immunized through a voluntary mass-immunization program, but the response of physicians to the program was disappointing. Outbreaks of rubella that occur in hospitals with prenatal clinics are of special concern. Testing of all employees for rubella antibody and immunization of those determined to be seronegative should be considered.

Adolescent↗
PubMed1980

Randomised clinical trial of perioperative cefazolin in preventing infection after hysterectomy.

To determine the efficacy of perioperative cefazolin in preventing pelvic and wound infections after elective non-radical hysterectomy, a randomised, placebo-controlled, double-blind clinical trial was done. Among 86 patients undergoing vaginal hysterectomy, those who received three perioperative 1 g doses of cefazolin (44) had significantly fewer pelvic infections (21% vs. 2%); less standard febrile morbidity (31% vs. 14%); shorter length of stay (LOS); and fewer courses of antibiotics postoperatively. There was no reduction in rate of urinary-tract infection (UTI) (21% vs. 23%). Among 429 women having abdominal hysterectomy, the 206 who received cefazolin had significantly lower rates of wound and pelvic infections (21% vs. 14%), UTI (21% vs. 9%), and febrile morbidity (20% vs. 14%). They also had shorter LOS and received fewer courses of antibiotics postoperatively. Use of perioperative cefazolin was not accompanied by more side-effects. Three doses of perioperative cefazolin seem to be safe, efficacious, and cost-effective in preventing infection after vaginal or abdominal hysterectomy.

Adult↗
PubMed1980

Serum antibody response to Bacteroides fragilis in women with abscesses following hysterectomy.

To determine the role of Bacteroides fragilis in the development of infectious complications following hysterectomy, serum antibody to the capsular polysaccharide was measured with a radioactive antigen-binding assay in 53 women before and several days after surgery. Patients with postoperative abscess formation had a significantly greater mean increase in antibody concentration (4.91 micrograms/ml) than those without complications (0.62 micrograms/ml), those with wound infection (1.90 micrograms/ml), those with pelvic cellulitis (0.63 micrograms/ml), and those with febrile morbidity (0.95 micrograms/ml). There were no significant differences among the latter 4 groups. The authors conclude that B fragilis may play an important role in abscess formation following hysterectomy, but is infrequently involved in other infectious complications of this procedure.

Abscess↗