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PubMed1989

Evidence for spread of the human immunodeficiency virus epidemic into low prevalence areas of the United States.

Reports of an increased proportion of AIDS cases occurring in small and medium-sized cities suggest that the HIV epidemic may be spreading into locations that were previously characterized by their low HIV antibody prevalences. Studying the question of the geographic spread of the HIV infection epidemic (rather than the AIDS epidemic) has been difficult largely because most serial seroprevalence data have been gathered from cohorts of high risk individuals (e.g., homosexual/bisexual cohorts) in New York City, San Francisco, and other geographically circumscribed areas. The U.S. military applicant HIV screening data were used in the current report to examine rates and 24 month temporal trends in geographic areas characterized by their HIV endemicities. The data examined concern the seven most populous states and four hyperendemic metropolitan areas located within those states (New York City, Miami, Houston, and San Francisco). In the nonepidemic regions, seroprevalence rates increased among black and white applicants. In the four epidemic urban areas, only young black applicants had higher HIV seroprevalence rates during the second 12 month period. Six of the seven nonepidemic regions had positive HIV seroprevalence trends, and these trends were significant in Florida, California, Texas, Illinois, and Ohio. The increases in these regions were greater for young blacks (30% excess for year 2 vs. year 1) compared to young whites (12% excess for year 2 vs. year 1). These data provide evidence of birth year specific increases in seroprevalence over time occurring in presumed low HIV prevalence areas. These increases cannot be due to, but are observed in spite of, biases associated with increasing self-selection over time.

Acquired Immunodeficiency Syndrome↗

PubMed1989

Restoration to normal body composition by VLCD: a comparison of post obese and lean subjects questions BMI 25 as diet limit.

Body composition was assessed in naturally lean female subjects who never had need to diet. At BMI 21-22 their body weight distribution of 75 per cent FFM and 25 per cent fat was compared with subjects who had dieted below BMI 25 by various conventional self-selected diets; subjects who had dieted to BMI 21-22 by VLCD and subjects who were dieting with VLCD but were still above BMI 25. These body composition studies support values of BMI 22-22 as a better estimate of desirable weight in women than BMI 25. At BMI 21-22 the distribution of body weight between fat and FFM of post VLCD dieters matches that of normal lean women.

Body Composition↗

PubMed1989

[Varicosities of the lower extremities in workers in positions requiring continuous standing or sitting positions].

An epidemiological study of the prevalence of varicose veins of lower extremities was carried out in an industrial population of 434 men and 345 women. A statistically significant (p less than 0.05) association between the varicose disease and duration of work was found in all groups of workers, except for women sitting at work. Decrease in the prevalence of varicose veins after 20 years of employment may be explained at least partly, by the factor of self-selection in the industry. However, there was no difference in the prevalence of varicose veins between workers standing and those sitting at work.

Female↗

PubMedDate not supplied

Effects of music and imagery on physiologic and self-report of analogued labor pain.

Two studies were conducted to examine the effects of music on analogued labor pain using volunteer nulliparous subjects who were randomly assigned to treatment groups (n = 10 per group). Assessments of the treatments were made in a 1-hour session involving twenty 80-second exposures to a laboratory pain stimulus patterned to resemble labor contractions. In the first experiment, it was hypothesized that subjects listening to easy-listening music would report lower pain ratings and cardiovascular responses than subjects listening to rock music, self-selected music, or a dissertation (placebo-attention) and subjects in a no-treatment control group. No significant group effects were found; significant time effects were found for heart rate, systolic and diastolic blood pressure. Subjects spontaneously reported using imagery as a pain reduction technique. In the second study a combination of music and imagery was examined by randomly assigning subjects to one of five groups: self-generated imagery with music (SIM), guided imagery with music (GIM), self-generated imagery without music (SI), guided imagery without music (GI), or no-treatment control. Again, no significant group effects were obtained. Significant time effects were obtained for heart rate, systolic and diastolic blood pressure.

Adult↗

PubMed1989

Quality of care in family practice: does residency training make a difference?

As the proportion of physicians who enter residency training in family practice steadily increases, so does the need to evaluate the impact of their training and postgraduate education on the quality of care in their practices. We audited the practices of 120 randomly selected family physicians in Ontario, who were separated into four groups: nonmembers of the College of Family Physicians of Canada (CFPC), members of the CFPC with no certification in family medicine, certificated members without residency training in family medicine and certificated members with residency training in family medicine. The practices were assessed according to predetermined criteria for charting, procedures in periodic health examination, quality of medical care and use of indicator drugs. Generally the scores were significantly higher for CFPC members with residency training in family medicine than for those in the other groups, nonmembers having the lowest scores. Patient questionnaires indicated no difference in satisfaction with specific aspects of care between the four groups. Self-selection into residency training and CFPC membership may account for some of the results; nevertheless, the findings support the contention that residency training in family medicine should be mandatory for family physicians.

Adult↗

PubMed1989

Public cholesterol screening: motivation for participation, follow-up outcome, self-knowledge, and coronary heart disease risk factor intervention.

We used a mailed questionnaire and telephone interviews with 1717 shopping center screenees whose total serum cholesterol was greater than 200 mg/dl. Our specific aim was to assess the subjects' motivations for participation in cholesterol screening, their follow-up outcome, their self-knowledge, and any coronary heart disease risk factor intervention. Of 1717 questionnaires mailed, 507 (30%) were returned; 64 of 100 subjects randomly selected for telephone interview could be contacted, and 61 were interviewed. Responses to the questionnaire and telephone interview were congruent, indicating little self-selection response bias. Before the cholesterol screening, 50% and 67% of questionnaire and telephone interview subjects knew their cholesterol levels. The nine most commonly cited reasons for cholesterol screening participation were: a desire to "watch" health (72%), convenience (70%), low cost (64%), to recheck previously measured total cholesterol (54%), publicity (34%), curiosity (30%), a relative with premature coronary heart disease (27%), the subjects' obesity (26%), and a relative's high cholesterol level (25%). As a result of cholesterol screening, 65% and 63% of questionnaire and telephone interview subjects, respectively, followed up with their doctors; 67% and 56%, respectively, had total cholesterol remeasured, but 17% and 18%, respectively, were told to "do nothing." At their doctors' follow-up, 74% and 51% of questionnaire and telephone interview respondents, respectively, began a low-saturated fat, low-cholesterol diet; 10% and 15% started taking a cholesterol-lowering drug. As a result of cholesterol screening, 76% and 85% of questionnaire and telephone interview subjects, respectively, changed their diets; 78% and 84% lowered their dietary cholesterol intakes, 62% and 74% increased their fiber intakes, 49% and 57% tried to lose weight, and 44% and 43% increased their exercise. Of questionnaire subjects, 94% thought that by lowering cholesterol, coronary heart disease risk could be reduced; 95% had become more aware of cholesterol in the last 5 years. Of telephone interview subjects, 91% concluded that cholesterol screening had motivated them to reduce cholesterol levels. Public cholesterol screening is convenient, inexpensive, facilitates self-knowledge about cholesterol, stimulates follow-up, and motivates physician and subject-guided dietary changes to reduce cholesterol levels and coronary heart disease risk.

Adult↗

PubMed1989

[Physiological responses to heat and effort and complaints of hyperperspiration].

The sensation of hyperperspiration is a common complaint in hot, humid climates. 54 men and 20 women, 18-47 years old, who had this complaint and 27 male control subjects were examined at rest and after 1 hour of mild exercise (40W) under conditions of heat stress (37 degrees C, 50% relative humidity). During exposure to heat rectal and skin temperatures and heart rate were measured every 15 min. Sweat rate was calculated for the entire period of exposure and sweat gland density was measured at 0, 60 and 120 min. Only insignificant deviations from baseline values were noted at rest. During exercise the sweat rate of the men with the complaint was within normal limits and similar to that of the control men (285 +/- 75 ml/m2 vs 272 +/- 48). Matching for age and V02 max revealed no significant differences in physiological responses of men with and those without the complaint. Women with the complaint lost 25-30% less fluid (226 +/- 67 ml/m2) and their concentrations of active sweat glands were lower than in either of the male groups. 2 men and 1 woman with the complaint and 1 control lost 400-425 ml/m2 during exercise, the upper limit of normal. Only 1 subject showed hyperperspiration (855 ml/m2) during the test. All physiological parameters examined in these 5 subjects were within normal limits. It is concluded that the complaint of hyperperspiration in our self-selected group is basically a subjective feeling and has no pathological basis. None of the subjects was heat intolerant.

Adult↗

PubMed1989

Correlates of certification in family medicine in the billing patterns of Ontario general practitioners.

There is conflicting evidence as to whether physicians who are certified in family medicine practise differently from their noncertified colleagues and what those differences are. We examined the extent to which certification in family medicine is associated with differences in the practice patterns of primary care physicians as reflected in their billing patterns. Billing data for 1986 were obtained from the Ontario Health Insurance Plan for 269 certified physicians and 375 noncertified physicians who had graduated from Ontario medical schools between 1972 and 1983 and who practised as general practitioners or family physicians in Ontario. As a group, certificants provided fewer services per patient and billed less per patient seen per month. They were more likely than noncertificants to include counselling, psychotherapy, prenatal and obstetric care, nonemergency hospital visits, surgical services and visits to chronic care facilities in their service mix and to bill in more service categories. Certificants billed more for prenatal and obstetric care, intermediate assessments, chronic care and nonemergency hospital visits and less for psychotherapy and after-hours services than noncertificants. Many of the differences detected suggest a practice style consistent with the objectives for training and certification in family medicine. However, whether the differences observed in our study and in previous studies are related more to self-selection of physicians for certification or to the types of educational experiences cannot be directly assessed.

Canada↗

PubMed1986

Ethanol drinking by vervet monkeys (Cercopithecus pygerethrus): individual responses of juvenile and adult males.

Unrestricted access of vervet monkeys to a palatable solution of ethanol resulted in chronic intake or abstinence. Self-selected dose averaged 4.42 g/kg body mass/day. Growth of juveniles was not grossly affected. In plasma, chronic ethanol intake was associated with lower average K and Cl values, increased gamma glutamyl transpeptidase in some adults, and higher average total cholesterol. Neither hepatic histology nor haematology were affected by chronic ethanol intake.

Age Factors↗

PubMed1989

Energy intake and dietary macronutrient content in women with anorexia nervosa and volunteers.

This study was designed to compare the dietary intakes of patients with anorexia nervosa and normal controls. Twenty-four patients hospitalized for treatment of anorexia nervosa were compared with 10 normal controls. Patients ate a self-selected diet and maintained their admission weight to within 1.0 kg during this period (19 +/- 3 days). Food chosen by each subject was weighed before and after meals, and intake was determined to be the difference. Intakes of food energy, protein, fat, and carbohydrate were calculated. Patients were closely monitored to ensure that no disposal of food occurred. Patients with anorexia nervosa had a mean daily energy intake of 1,017 +/- 54 kcal (mean +/- SEM), significantly lower than the mean energy intake for controls (1,651 +/- 108 kcal). Similarly, mean intakes of macronutrients (41 +/- 4 gm protein, 34 +/- 2 gm fat, and 136 +/- 9 gm carbohydrate) were significantly lower for patients than for controls (68.5 +/- gm protein, 65 +/- 6 gm fat, and 204 +/- 13 gm carbohydrate). However, when protein, fat, and carbohydrate were assessed as a percent of total calories, there were no significant differences between patients and controls. There were also no significant differences in calories consumed per kilogram body weight. Underweight patients with anorexia nervosa who maintain their weight on an unrestricted hospital diet have energy intake per kilogram body weight and dietary macronutrient content indistinguishable from those of normal women.

Adult↗

PubMed1989

Relation of family physician or specialist care to obstetric interventions and outcomes in patients at low risk: a western Canadian cohort study.

To determine the relation of family physician or specialist care to intrapartum interventions and outcomes, we carried out a historical cohort study of 1456 obstetric patients at low risk admitted between Nov. 15, 1984, and Mar. 15, 1986, to a western Canadian teaching hospital. The patients were classified as being at low risk on admission by means of chart review. Family physicians and specialists were found to have similar rates for most of the interventions measured, although the interventions for which significantly different rates were found suggest a less interventionist style of intrapartum care by family physicians. There were no significant differences in maternal or neonatal outcomes except for a higher proportion of infants weighing less than 2500 g among primigravid women cared for by family physicians compared with those under the care of specialists. Self-selection of physician specialty by patients resulted in differences in the demographic characteristics of the two patient populations. The findings support the continued involvement of family physicians in the provision of obstetric care.

Adolescent↗

PubMedDate not supplied

The life space drawing as a measure of social relationships.

The life space drawing was prospectively assessed as a predictor of 12-month morbidity in 27 white female participants of a clinical trial. Women who subsequently experienced a high rate of self-reported morbidity (greater than or equal to 3 restricted-activity days per month) had a higher proportion of interpersonal relationships characterized by poor communication than did women with less than or equal to 2 restricted activity days per month. The quality of the relationship with a spouse/significant other appeared to be a particularly strong predictor of morbidity in this small self-selected group of women.

Adult↗

PubMed1986

Cocaine treatment outcome: cocaine use following inpatient, outpatient, and no treatment.

Based upon a sample of 83 cocaine users self-selected into one of 3 programs, several conclusions seem possible. There seems to be little difference in Ss populations who choose hospital, outpatient or self-help/no treatment. Current hospital aftercare programs may not be appropriately oriented for cocaine users. It appears the hospital program in this study retained fewer than 30% of the Ss in aftercare. Outpatient treatment for cocaine dependency is a viable form of treatment which Ss will participate in for up to 6 months on a fee for service basis. Only about 20% of the Ss who were referred to self-help groups attended more than one meeting. Preliminary outcome data suggest that outpatient treatment may result in a lower relapse rate to cocaine than hospital or no treatment. However, this conclusion is extremely guarded due to a large number of methodological issues and the short follow-up period. Relapse to cocaine use is higher among Ss who returned to alcohol or marijuana.

Cannabis↗

PubMed1979

Potential effect of demographic and other variables in studies comparing morbidity of breast-fed and bottle-fed infants.

Comparing the morbidity of breast-fed and bottle-fed infants is confounded by inherent differences in breast-feeding and bottle-feeding mothers and their infants. Self-selection introduces complex variables encompassing much more than milk source used for infant feeding. Reasons for selecting breast or bottle feeding relate to demographic, socioeconomic, educational, ethnic, cultural, and psychological factors, as well as maternal and infant physical and emotional health. Many of the differences in the maternal populations may affect infant care practices, access to medical care, and infant health status. Studies published to date have not quantified these confounding effects and other potential biases in comparing morbidity to breast- and bottle-fed infants and the relationship between milk source and incidence of infantile disease remains in question. There is need for more cautious use of the available data and investigators must seek ways to design future studies to take into account the differences between breast-feeding and bottle-feeding mothers that affect both reported and actual infant morbidity.

Bottle Feeding↗

PubMedDate not supplied

[Treatment of the sick elderly in households accommodating several generations].

Multigenerational households with widowed persons aged 70 and more have been studied in order to determine the relationship between the following two groups of variables: (a) variables in the aged person describing the existence and degree of an organic mental impairment due to a dementive process and of other signs of physical illnesses. (b) variables in her daughter or daughter in law consisting of selfratings of psychosomatic complaints and of attitude-scales. Results were as follows: (a) If there were indications of personality changes due to an organic brain syndrom the relatives had a lower degree of life-satisfaction and more frequently suffered from psychosomatic symptoms and interpersonal stress than those, whose old relatives showed an unaltered personality. (b) A great number of comparisons failed to show any statistical differences. Especially severe physical illness, organic brain syndrome and the need for physical care were not related to life satisfaction, psychosomatic complaints, stress due to emotional involvement and the attitude towards home-care. Our attempt to explain the missing correlations led to the following factors: the small size of the sample, self-selection of the sample and possibly inappropriate operationalisation and measurement of variables. In respect to these results the ongoing study will be modified in some details: There will be a qualitative analysis of transcribed semi-structured interviews. The proportion of families with severely demented relatives will be increased. In an additional step we shall examine families, who have decided to transfer their old member into an institution.

Aged↗

PubMed1978

The effect of energy and nitrogen intake upon urea production in children with uremia and undernutrition.

Children with severe uremia who had anorexia were observed in a clinical study center where dietary energy and nitrogen intake could be compared with urea nitrogen production (UNPr). The children received a supplement of dextrose and amino acids at night, ate a self-selected diet and were encouraged to use carbohydrate supplements. Energy intake varied from 22 to 110 kcal/kg/day and nitrogen intake from 105 to 323 mg/kg/day. UNPr was reciprocally related to energy intake. Nitrogen intake minus UNPr, an index of nitrogen balance, was positively related to energy intake. UNPr was not related to nitrogen intake. Nitrogen intake (NI) and NI-UNPr were correlated and the slope of the regression was 1.15. We inferred from the data that low energy intakes (less than 60 kcal/kg/day) were associated with catabolic losses of body protein. Intakes above that level were associated with a low and stable rate of UNPr. The level of energy and nitrogen intake within the range observed limited the rate of nitrogen retention. Once maintenance requirements for energy and nitrogen were satisfied, the efficiency with which nitrogen was used for net protein synthesis was very high.

Adolescent↗

PubMed1979

Gastric secretory and humoral responses to anticipated feeding in five men.

It is believed that humans anticipate appetizing meals by increasing vagally mediated gastric acid secretion. Studies were conducted on 5 normal male volunteers to characterize further the secretory response to anticipated meals. Plasma gastrin and glucose levels were monitored to assess the possibility that these humoral factors participated in the observed secretory changes. Subjects were not fed for 22 hr and were intubated at 10 AM. Basal gastric collections were begun, and at 1 PM on different days, subjects either (a) selected meals of choice prepared in their presence for 1 hr before nasogastric tube withdrawal and meal ingestion or (b) were not food-teased or fed. Gastric collections were obtained every 10 min during the "test" hour (1-2 PM) during both (a) and (b) studies and titrated for gastric acid. Blood samples for plasma glucose and RIA gastrin were obtained during basal and test hours every 10 min. Pentagastrin-stimulated maximal acid output studies were conducted on all subjects on separate days. Results showed a progressive and statistically significant rise in gastric acid secretion when an appetizing, self-selected meal was anticipated. The magnitude of this rise was 55% of the mean pentagastrin-induced acid response. This acid response did not correlate with changes in plasma glucose or gastrin. The study demonstrated that pure psychic stimulation may be as effective an acid stimulant as sham feeding.

Adult↗

PubMed1977

Enrollment choice in a mutli-HMO setting:the roles of health risk, financial vulnerability, and access to care.

Results of an analysis of enrollment decisions in HMO-type plans are reported. Previous studies concern dual-choice situations; this paper deals with a quadruple-choice situation involving one open- and two closed-panel HMO-type plans as well as Blue Cross/Blue Shield (BC/BS). The risk-vulnerability hypothesis is disaggregated into its components and the results show that there is no adverse health risk self-selection in an employed population. The hypothesis of economic vulnerability is maintained when tested in terms of per capita income rather than the previously used measure of family income. It is shown that those who enroll in any HMO-type plan are younger and have younger and larger families and lower per capita income than those who do not. No meaningful differences in terms of health status, health concerns, or prior utilization are found. Of the few differences found between those who enroll in closed- and open-panel HMO-type plans, having a private physician as the usual source of care is the most significant: those with an established physician relationship who join any HMO-type plan tend to follow their physician into the open-panel plan. The results should not be generalized to situations involving premium differences since the premium cost to subscribers in any of the plans considered here was fully paid by the employer. The validity of the results in terms of nonfinancial factors, on the other hand, is enhanced by the removal of cost considerations.

Adolescent↗