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PubMed1979

Consumer impact of a Cold Self-Care Center in a prepaid ambulatory care setting.

A Cold Self-Care Center was developed to be an alternative to professional care and to encourage more active involvement of consumers in their own care. A sample of the self-selected user population (n = 74) was studied by comparison with a random sample of plan members (n = 104), and the program was evaluated for cost, consumer satisfaction, and impact on behavior, knowledge and attitudes. Users demonstrated higher levels of knowledge about cold care than non-users, indicated more dependency on professional resources, and differed in health-related attitudes and cold-care behavior. The Cold Self-Care Center appears to have had little impact on self-medication behavior. However, it did affect care-seeking behavior. Knowledge of criteria for seeking professional care was greater than in non-users; 20 per cent sought professional care, and 6 per cent anticipated seeking professional care for future colds. General satisfaction with the program was quite high. Speed and ease of use were cited most often as reasons for satisfaction. The Center also was demonstrated to have a favorable impact on clinic costs. A flexible system which is convenient to use and which retains access to professional care when appropriate both can relieve clinic overload and meet the needs of a large percentage of cold patients.

Common Cold↗

PubMed1978

A program of heart disease intervention for public employees. A five year report.

The five-year experience involving over 800 employees has effected reduced coronary risk factors, improved physical work capacity and maximal oxygen uptake and reduced employee absenteeism from personal sick leave. As in all instances where the self-selection process confounds the nature of the results, the extent of extrapolation from these data must be guarded. Nevertheless, the results support and further extend previous studies suggesting a reduction of CVD following formal behavior and life-style modification. It is the opinion of the authors that similar programs can be implemented where health services, flexible hours, agency cooperation and salaried coordinators can be assembled.

Adolescent↗

PubMed1979

Sibship asymmetries of rhesus blood groups in the presence of maternal antibodies.

The genotypes of the children of R1r, R2r, and R1R2 fathers, and Rh-immunized rr mothers, were examined. R1r fathers had an excess of R1r over rr children, and R1R2 fathers had an excess of R1 r over R2r children. These asymmetries confirm the findings of a previous study. The possibilities of artefactual self-selection, of genotyping errors, and of errors in assigning paternity, were examined and excluded. Alternative models of genetic transmission and of antigenic structure were studied, but no basis for explaining the findings was found or formulated. Three possible biological explanations were formulated including (a) asymmetric segregation of the rhesus genes, (b) selective early fetal loss, and (c) a selective effect upon the performance of sperms bearing different haplotypes. The first of these three appeared unlikely. The data did not provide a basis for supporting or rejecting or differentiating the other two.

ABO Blood-Group System↗

PubMed1977

Marathon running and immunity to atherosclerosis.

This is an interim report of an on-going study of deaths in 42-km men. The absence of fatal ASCVD in these athletes can not be construed as evidence for the protective role of exercise alone. The ability to run 42 km depends on many factors. Exercise is only one. Avoiding tobacco is another. Dietary factors also play a role. It has not been feasible to remove one of these factors while maintaining the ability to cover the 42 km distance. Some 42-km men claim that megadoses of ascorbic acid protect them from collagen injury. This is supported by animal studies that show increased collagen synthesis proportional to ascorbic acid intake up to dosage levels that would equal 10 grams per day for humans. Their self-selected macrobiotic diet contains a high ratio of peanuts:steak resulting in a high P/S ratio (polyunsaturates/saturates). Dietary manipulation quickly effects their ability to train. Smoking is so rare among these runners that it must be related to specific effects, such as a catalytic agent in tobacco smoke converting linoleic acid into a toxic lipid oxide. Noakes and Opie recently confirmed again (May, 1976) that no cases of "death due to coronary atherosclerosis" have been recorded in marathon finishers. If this holds true for the second 10-year period of this study, then marathon runners will have joined the longshoremen by earning life-long protection against ASCVD. These longshoremen burned 1,876 kcals on the job, equivalent to a 30-km run. Roberts and Straus suggest that many factors can cause atherosclerosis. Only time will tell whether the marathoner is protected from all of them.

Adult↗

PubMed1977

Errors arising through using the Harvard tables and percentage levels of median weight-for-age in assessing nutritional status.

A self-selected sample of 417 urban and 379 rural preschool children attending the under-5s clinics was weighed in Sierra Leone. The individual weights were related to the weight-for-age Harvard 3rd centiles and 80% levels of the Harvard medians. In this analysis there were considerable discrepancies between the sexes. Further investigation showed that the distribution of the weight-for-age Harvard centiles for girls is much wider than the distribution of the Harvard centiles for boys. These distributions appear to be unusual when compared with those from London and Hong Kong studies. Accordingly, use of the weight-for-age Harvard centiles may lead to inaccuracy in the assessment of the nutritional status of preschool children. The "percentage method" as suggested by Jelliffe (1966) and Gomez et al. (1956) does not take account of the normal range of distribution of the standards. This study has shown that the 80% levels of sex-specific median weight-for-age occupy positions as much as 600 g below the sex-specific 3rd centiles for Hong Kong Chinese children, while the 80% levels closely follow the 3rd centiles for London children in the preschool age group. Thus the Hong Kong 80% levels are not comparable with the London 80% levels. Therefore, the "percentage method" appears to be misleading in the assessment of nutritional status using weight measurements.

Age Factors↗

PubMed1979

Comparison of respiratory variables in grain elevator workers and civic outside workers of Thunder Bay, Canada.

We compared respiratory variables in 441 grain elevator workers with 180 civic outside laborers in Thunder Bay. The grain handlers had a lower frequency of both positive skin reactions to pollens and molds and a family history of asthma, which suggests that they may have been self-selected for a decreased tendency to develop allergic respiratory disease. There was a higher frequency of cough and rales and a small decrease in forced vital capacity and forced expiratory volume in one sec among the grain handlers, as compared to the civic workers matched for smoking. However, these differences between grain and nongrain workers were small in comparison to those between smokers and nonsmokers. There was no clear indication of a worsening of respiratory functions that could be attributed specifically to duration of employment as a grain elevator worker.

Adult↗

PubMedDate not supplied

Effects of the living environment on activity and use of time.

Exposure to an environment with increased opportunities resulted in increased activity among a group of elderly persons, compared to similar people in unenriched environments. Findings support the hypothesis that unmet need for activity existed among the group, all of whom had been matched to the enriched environment by staff and self-selection, and the hypothesis that environmental intervention is potent in influencing behavior, even in old age. Persistence of the relative elevation in activity over eight years and concomitance with other indexes of well-being suggest that appropriate environment intervention which expands activity opportunities is beneficial. Congruity between the person's needs and the environment's resources is central. Individual differences in need for activity interacted with opportunity in accounting for outcomes.

Activities of Daily Living↗

PubMed1977

Analysis of clinically occult and mammographically occult breast tumors.

Findings by xeromammography and clinical examination were compared in 16,000 self-selected women aged 45-64 who participated in a voluntary breast cancer screening program. A total of 138 malignancies were detected: 108 (78%) by mammography and 78 (57%) by clinical examination. Mammography was more effective for large breasts, fatty breasts, and in older women. Conversely, clinical examination was more effective for small breasts, dense breasts, and retroareolar lesions. Clinical detection decreased strikingly for lesions with negative lymph nodes, in situ and microinvasive lesions, deeply situated lesions, and lesions where microcalcifications were the sole mammographic finding.

Age Factors↗

PubMed1977

Neuroticism and proxemic behavior.

The relationship between proxemic behavior and neuroticism was examined. 50 male and 43 female subjects individually self-selected seats in a classroom where they were administered the Eysenck Personality Inventory by one of four experimenters (two male, two female). A significant relationship was found between proxemic distance and both neuroticism and experimenter's sex.

Female↗

PubMed1978

Serological evidence for a high incidence of transmission of Rickettsia tsutsugamushi in two Orang Asli settlements in Peninsular Malaysia.

Two communities of Orang Asli (aborigines) in Peninsular Malaysia were observed for evidence of Rickettsia tsutsugamushi infection over periods of 1-8 mo. Sequential sera were examined for antibody by the indirect immunofluorescence test. The incidence of infection in the two self-selected populations in the two communities was calculated to be 3.9% per month and 3.2% per month.

Adolescent↗

PubMed1979

Dietary manipulation of serum triglycerides.

A group of children who had been treated for protein-energy malnutrition with a high-energy, high-faty diet, presented very low levels of fasting serum triglycerides (50.8 +/- 5.9 mg/dl). When the diet was changed to a high-energy, low-fat formula, these levels increased rapidly to normal values (104.9 +/- 19.2 mg/dl). Reversing the dietary change produced the opposite effect within 2 days. This effect was also studied in 14 normal adults, who received a high-fat diet ad libitum during 5 days. Meals were prepared from common foodstuffs with a high fat content. The hypotriglyceridemic effect occurred in all volunteers. A close relationship was observed between the initial triglyceride concentration and the decrement produced by the high-fat diet (r = 0.97), which did not affect serum cholesterol levels. No consistent response of serum free-fatty acids was detected, while serum proteins remained within normal values. Despite the rather high energy intake, most subjects lost weight during the experimental period. The level of fasting serum triglycerides of the adult volunteers was negatively correlated to the fat content of their self-selected diets. These results are discussed in relation to current ideas about fat requirements.

Adult↗

PubMed1976

Observations on the analgesic effects of needle puncture (acupuncture).

The present study was undertaken in order to investigate the analgesic effect of needle puncture in a small self-selected group of patients with chronic or acute pain, and to examine the factors which determine success or failure of this treatment modality. We have found that in chronic painful conditions, needle puncture may be very effective in producing at least transient analgesia. It also can produce permanent relief of acute (self-limited) pains. Needle puncture was not helpful in the management of pain resulting from nerve damage. High score on psychometric indicators of anxiety and depression is a significant predictor os successful needle puncture analgesia in patients with chronic pain. Comparison of our results to studies of counterirritation indicate that the analgesia produced by needle puncture involves a mechanism similar to that of counterirritation-induced analgesia.

Acupuncture Therapy↗

PubMed1978

Update of naltrexone treatment.

To summarize, then, our work with naltrexone in a multi-modality treatment program indicates that it appeals to about 5-10 percent of narcotic addicts--those who conciously want to obtain drug-free status. It does significantly attentuate the effect of narcotics to the extent that they lose their reinforcing properties, and it has minimal side effects. Although we treated a self-selected population, it is noteworthy that about 10 percent of those who remained on naltrexone for more than a week were still opiate free 6 months after cessation of treatment. For some it appeared to be a turning point in their lives. It was the first time in years that they could live in their neighborhood and not be either intoxicated or occupied with the pursuit of narcotics. Our behavioral studies have identified a number of conditioned psychophysiological responses associated with the self-injection ritual. So far, although we have succeeded in extinguishing some of these responses, this has not resulted in an improved clinical outcome. We are currently working on more comprehensive behavioral treatments, but the clinical significance of these conditioned responses is uncertain at present.

Adult↗

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↗