Asthma prevalence disparities and differences in sociodemographic associations with asthma, between Native Hawaiian/Other Pacific Islander, Asian, and White adults in Hawaii - Behavioral Risk Factor Surveillance System (BRFSS), 2001-2010.

OBJECTIVES: Despite high asthma prevalence, relatively little is known about the epidemiology of asthma in Hawaii or among Native Hawaiian/Other Pacific Islanders (NHOPI). We sought to better characterize racial/ethnic differences in asthma prevalence and in sociodemographic factors associated with asthma among Hawaii adults. DESIGN: We conducted multivariable logistic regression using 2001-2010 Behavioral Risk Factor Surveillance System data from Hawaii, and computed adjusted prevalence and ratios. RESULTS: Asthma prevalence markedly varied between self-identified census categories of race in Hawaii, with NHOPI having the highest estimates of both lifetime (20.9%, 95% confidence interval [CI]: 19.5%-22.4%) and current (12.2%, CI: 11.2%-13.3%) asthma. Highest asthma prevalence among NHOPI persisted after controlling for potential confounders and within most sociodemographic categories. Among females Asians reported the lowest asthma prevalence, whereas among males point estimates of asthma prevalence were often lowest for Whites. Females often had greater asthma prevalence than males of the same race, but the degree to which gender modified asthma prevalence differed by both race and sociodemographic strata. Gender disparities in asthma prevalence were greatest and most frequent among Whites, and for current asthma among all races. Sociodemographic factors potentially predictive of adult asthma prevalence in Hawaii varied by race and gender. CONCLUSION: Asthma disproportionately affects or is recognized more often among women and NHOPI adults in Hawaii, and occurs less or is under-reported among Asian women. The sociodemographic characteristics included in this study's model did not explain asthma disparities between races and/or gender. This investigation provides a baseline with which to plan additionally needed prevention programs, epidemiological investigations, and surveillance for asthma in Hawaii.

Immediate and longterm effects of immune stimulation: hypothesis linking the immune response to subsequent physical and psychological wellbeing.

We hypothesize that antigenic stimuli in susceptible persons during key developmental life stages alters neuroendocrine-immune organization and leads to the development of aberrant immune and neuroendocrine responses to subsequent environmental stressors, with longterm physical and psychological consequences. The release of interleukin-1beta (IL-1beta) and other proinflammatory cytokines associated with the immune response during times when individuals are most vulnerable to the effects of environmental influences activates the hypothalamic-pituitary-adrenal (HPA) axis and leads to maladaptive responses to subsequent stressors. The primed HPA axis is reactivated by proinflammatory cytokines, resulting in the secretion of corticotropin-releasing hormone (CRH) and cortisol, followed by physical and psychological effects that feedback on the HPA axis to produce an array of outcomes affecting general wellbeing. Through the release of histamine and other mediators and their effects on the mast cell-leukocyte cytokine cascade, immune stimuli in susceptible persons increase allergic inflammation and magnify stressors' effects through the release of HPA-axis-activating cytokines, such as IL-1beta, that drive the axis and reinforce the physiological and behavioral effects. Thus, specific proinflammatory cytokines and allergic reactions initiate, promote, and maintain immune-stimulus-associated HPA axis activity, and with CRH and cortisol, participate in a positive feedback loop, resulting in aberrant, maladaptive responses to physical or psychological stressors, with outcomes such as depression, hyperalgesia, and pain-related behavior.

The Disability Index of the Health Assessment Questionnaire is a predictor and correlate of outcome in the high-dose versus low-dose penicillamine in systemic sclerosis trial.

OBJECTIVE: To explore the clinical implications of a score of > or =1.0 on the Disability Index of the Health Assessment Questionnaire (HAQ DI) at the first patient visit, and to examine the implications of improvement in HAQ DI score over 2 years in a cohort of systemic sclerosis (SSc) patients with diffuse cutaneous scleroderma. METHODS: SSc skin and visceral involvement was assessed in 134 SSc patients with diffuse scleroderma (mean +/- SD disease duration of 10 +/- 4 months) when they entered a multicenter drug trial and again 2 years later. Mortality and the occurrence of scleroderma renal crisis were assessed for a mean +/- SD of 4.0 +/- 1.1 years. Logistic and linear regression analyses were used to examine the relationship of the baseline HAQ DI score to morbidity, mortality, and visceral involvement, as well as the relationship of changes in the HAQ DI score to changes in physical examination, laboratory, and functional variables over 2 years. RESULTS: A baseline HAQ DI score of > or =1.0 was predictive of mortality (odds ratio 3.22, 95% confidence interval 1.097-9.468) over 4 years. Multivariate linear regression demonstrated that a model which included the erythrocyte sedimentation rate at baseline (P = 0.005) and changes at 2 years in the swollen joint count (P = 0.002), total skin score (P = 0.005), and white blood cell count (P = 0.005) best explained the change in HAQ DI score over 2 years (R2 = 0.528). The HAQ DI score and total skin score at baseline were highly correlated (correlation coefficient 0.368), as were changes in the HAQ DI score and the total skin score over 2 years (correlation coefficient 0.492). Although the HAQ DI score was heavily influenced by hand dysfunction at baseline and at 2 years, improvement (reduction) in the HAQ DI score over 2 years was related to factors other than hand dysfunction. CONCLUSION: A baseline HAQ DI score of > or =1.0 predicted mortality over 4 years. Improvement in the HAQ DI score in these patients with diffuse scleroderma was associated with improvement in skin thickening, hand function, oral aperture, lung function, signs of arthritis, serum creatinine level, and the investigator's global assessment of improvement. The HAQ DI is a self-administered questionnaire that SSc patients can complete easily and rapidly and that gives the practicing physician important information about prognosis, patient status, and changes in disease course over time.

Skin thickness score as a predictor and correlate of outcome in systemic sclerosis: high-dose versus low-dose penicillamine trial.

OBJECTIVE: To study the clinical implications of a skin thickness score > or =20 at first visit and of softening of sclerodermatous skin in a cohort of systemic sclerosis (SSc) patients with diffuse cutaneous scleroderma. METHODS: Skin and visceral involvement were assessed in 134 SSc patients with diffuse scleroderma (mean +/- SD duration of SSc 10 +/- 4 months) as they entered a multicenter drug trial and again at 2 years of followup. Advent of mortality and scleroderma renal crisis (SRC) were assessed during a followup of 4.0 +/- 1.1 years (mean +/- SD). Logistic and linear regression were used to examine the relationship of baseline skin score to morbidity, mortality, and visceral involvement and the relationship of changes in skin score to changes in physical examination, laboratory, and functional variables over 2 years. RESULTS: A baseline skin score > or =20 was associated with heart involvement at baseline (odds ratio [OR] 3.10, 95% confidence interval [95% CI] 1.25-7.70) and was predictive of mortality (OR 3.59, 95% CI 1.23-10.55) and SRC (OR 10.00, 95% CI 2.21-45.91) over 4 years. Multivariate linear regression demonstrated that a model with skin score at baseline (P = 0.0078) and changes in large joint contractures (P = 0.0072), tender joint counts (P = 0.0119), handspread (P = 0.0242), and Health Assessment Questionnaire disability index (HAQ-DI) (P = 0.0244) explained the change in skin score over 2 years (R2 = 0.567). Multivariate logistic regression demonstrated that the investigator's global assessment of improvement was best explained by a model with skin score and HAQ-DI (R2 = 0.455). CONCLUSION: A baseline skin score > or =20 was associated with heart involvement at baseline and predicted mortality and SRC over the subsequent 4 years. Improvement in skin score in these patients with diffuse cutaneous scleroderma was associated with improvement in hand function, inflammatory indices, joint contractures, arthritis signs, overall functional ability, and the examining investigator's global assessment of improvement.

Effectiveness of influenza vaccination of day care children in reducing influenza-related morbidity among household contacts.

CONTEXT: A growing proportion of young children in the United States participate in day care, and these children are considered to be at high risk for influenza infection. Whether vaccinating day care children reduces household transmission of influenza is not known. OBJECTIVE: To evaluate the effect of vaccinating day care children on reducing influenza-related morbidity among their household contacts. DESIGN: Single-blind, randomized controlled trial conducted during the 1996-1997 influenza season. SETTING: Ten day care centers for children of US Navy personnel in San Diego, Calif. PARTICIPANTS: A total of 149 day care attendees (aged 24-60 months) and their families were randomized; 127 children and their 328 household contacts received 2 vaccine doses and were included in the analysis. INTERVENTIONS: Inactivated influenza vaccine was administered to 60 children with 162 household contacts, and hepatitis A vaccine as a control was administered to 67 age-matched children with 166 household contacts. MAIN OUTCOME MEASURES: Information regarding febrile respiratory illnesses and related morbidity for household contacts of influenza-vaccinated vs control children (subgrouped by influenza-vaccinated and unvaccinated contacts), obtained by telephone interviews with parents every 2 weeks from November 1996 through April 1997. RESULTS: Influenza-unvaccinated household contacts (n = 120) of influenza-vaccinated day care children had 42% fewer febrile respiratory illnesses (P =.04) compared with unvaccinated household contacts of control children. Among school-aged household contacts (aged 5-17 years), there was an 80% reduction among contacts of vaccinated children (n = 28) vs contacts of unvaccinated children (n = 31) in febrile respiratory illnesses (P =.01), as well as reductions of more than 70% in school days missed (P =.02), reported earaches (P =.02), physician visits (P =.007), physician-prescribed antibiotics (P =.02), and adults who missed work to take care of ill children (P =.04). CONCLUSIONS: These results indicate that vaccinating day care children against influenza helps reduce influenza-related morbidity among their household contacts, particularly among school-aged contacts. Future studies should be conducted in civilian populations to assess the full effect of vaccinating day care children against influenza. JAMA. 2000;284:1677-1682.

Studies of the 1996-1997 inactivated influenza vaccine among children attending day care: immunologic response, protection against infection, and clinical effectiveness.

A randomized, blinded, pilot study of influenza vaccine administered to children attending day care centers was conducted during the 1996-1997 winter. Vaccine efficacy in preventing serologically proven influenza virus infection was 0.45 (95% confidence limit [CL]: -0.02, 0.69) for influenza B and 0.31 (95% CL: -0.95, 0.73) for influenza A(H3N2). For both influenza A(H3N2) and B, children without preexisting hemagglutination inhibition (HI) antibody to these antigens had lower antibody responses to vaccine, were less likely to develop a serological response, and were more likely to develop serological evidence of influenza infection. Although there were no reductions in respiratory or febrile respiratory illnesses among all vaccinated children, there was a trend for reductions in such illnesses among vaccinated children with preexisting HI antibodies to influenza A(H3N2) and B. Therefore, immunologic priming in young children may be important for vaccine response and for protection against infection. Larger studies are needed in other influenza seasons to assess vaccine efficacy and clinical effectiveness.

Inhibition of tumor growth by poly(ethylene glycol) derivatives of anti-ErbB2 antibodies.

Poly(ethylene glycol) (PEG) modification of substances with antitumor activity was shown to enhance penetration into growing solid tumors and extend antitumor effects. Accordingly, PEG was introduced as a modifier to two types of monoclonal antibodies (N12 and L26) specific to the ErbB2 (HER2) oncoprotein. These antibodies suppress the growth of tumors overexpressing ErbB2 (e.g. N87 human tumor) and the effect of PEG on their antitumor activity was evaluated. Methoxy-PEG-maleimide conjugated to sulfhydryl groups at the hinge region of the antibodies impaired their antibody binding to N87 tumor cells and did not enhance the antitumor inhibitory activity in tumor-bearing mice. A branched N-hydroxysuccinimide-activated PEG (PEG2), conjugated through amino groups of the protein, was used for binding to the whole antibody (Ab) or to its monomeric Fab' fragment. When tested against N87 cells in vitro, the binding activity and antitumor cytotoxic effects of Ab-PEG2 were mostly preserved. PEG2 modification did not seem to alter the tumor-inhibitory activity of the antibodies in vivo and the same pattern of tumor development was observed during the first few weeks following administration. However, the stimulating effects of PEG were observed at later stages of tumor growth since tumor development was either slowed down or completely arrested. Furthermore, a second tumor implanted into the same mice during this later stage was significantly or completely inhibited, as compared to results in mice injected with the unmodified antibody. The Fab'-PEG2 monomeric derivative was also shown to be effective in inhibiting the growth of a second tumor. The extended and prolonged enhancing effect of PEG on the antitumor activity of antibodies or Fab' fragments directed against ErbB2 may be of importance in the treatment of ErbB2-overexpressing neoplasms.

Effects of diphtheria-tetanus-pertussis or tetanus vaccination on allergies and allergy-related respiratory symptoms among children and adolescents in the United States.

BACKGROUND: Findings from animal and human studies confirm that diphtheria and tetanus toxoids and pertussis (DTP) and tetanus vaccinations induce allergic responses; associations between childhood vaccinations and subsequent allergies have been reported recently. OBJECTIVE: The association of DTP or tetanus vaccination with allergies and allergy-related respiratory symptoms among children and adolescents in the United States was assessed. METHODS: Data were used from the Third National Health and Nutrition Examination Survey on infants aged 2 months through adolescents aged 16 years. DTP or tetanus vaccination, lifetime allergy history, and allergy symptoms in the past 12 months were based on parental or guardian recall. Logistic regression modeling was performed to estimate the effects of DTP or tetanus vaccination on each allergy. RESULTS: The odds of having a history of asthma was twice as great among vaccinated subjects than among unvaccinated subjects (adjusted odds ratio, 2.00; 95% confidence interval, 0.59 to 6.74). The odds of having had any allergy-related respiratory symptom in the past 12 months was 63% greater among vaccinated subjects than unvaccinated subjects (adjusted odds ratio, 1.63; 95% confidence interval, 1.05 to 2.54). The associations between vaccination and subsequent allergies and symptoms were greatest among children aged 5 through 10 years. CONCLUSIONS: DTP or tetanus vaccination appears to increase the risk of allergies and related respiratory symptoms in children and adolescents. Although it is unlikely that these results are entirely because of any sources of bias, the small number of unvaccinated subjects and the study design limit our ability to make firm causal inferences about the true magnitude of effect.

Cross-sectional associations of asthma, hay fever, and other allergies with major depression and low-back pain among adults aged 20-39 years in the United States.

Although low-back pain and depression are common comorbidities, the mechanisms responsible for their association remain unclear. The effects of proinflammatory cytokines on the hypothalamic-pituitary-adrenal (HPA) axis lead to the hypothesis that allergic reactions, as markers for inflammation-associated activation of the HPA axis, result in aberrant responses to subsequent stressors. Data from 6,836 US adults 20-39 years old from the Third National Health and Nutrition Examination Survey (1988-1994) were used. Subjects responded to questions regarding low-back pain in the past 12 months and history of asthma, hay fever, and other allergies. The history and onset of major depression were obtained from the Diagnostic Interview Schedule. Logistic regression modeling was used to estimate the associations between allergies and depression and low-back pain. Subjects with a history of any allergy were more likely to report low-back pain (odds ratio = 1.51; 95% confidence interval: 1.16, 1.96), to be diagnosed with major depression (odds ratio = 1.58; 95% confidence interval: 1.13, 2.21), and much more likely to have both major depression and low-back pain (odds ratio = 3.03; 95% confidence interval: 1.32, 6.92). Hypersensitivity reactions may prime the HPA axis to respond aberrantly to stressors, resulting in physical and behavioral consequences.

Correlates of the disability index of the health assessment questionnaire: a measure of functional impairment in systemic sclerosis.

OBJECTIVE: To evaluate functional impairment in systemic sclerosis (SSc) patients with diffuse cutaneous scleroderma at the time of entry into a trial of a therapeutic intervention (D-penicillamine). METHODS: The 20-item Disability Index of the Health Assessment Questionnaire (HAQ-DI) was administered to 134 patients as they entered a multicenter trial of high-dose versus low-dose D-penicillamine. All patients had diffuse SSc of < 18 months' duration. SSc patients who had severe organ system involvement and recent renal crisis and who were receiving prednisone > 10 mg/day were excluded from entry. Logistic regression modeling was used to examine the relationship of HAQ-DI scores to SSc skin and organ system involvement. Odds ratios (OR) and 95% confidence intervals (95% CI) were used to estimate effects. RESULTS: The mean (+/-SD) HAQ-DI score at entry was 1.04 +/- 0.67. Fifty-three percent of patients had HAQ-DI scores > or = 1.0 (signifying moderate-to-severe functional impairment). Multivariate logistic regression demonstrated that impaired fist closure > or = 23 mm (OR 4.24, 95% CI 1.68-10.70), reduced handspread < or = 175 mm (OR 4.5, 95% CI 1.80-11.24), joint tenderness count > or = 1.0 (OR 2.93, 95% CI 1.16-7.40), age > or = 43 years (OR 2.44, 95% CI 1.01-5.95), platelet count > or = 330,000/mm3 (OR 2.30, 95% CI 0.96-5.57), and female sex (OR 2.43, 95% CI 0.77-7.73) were the most important correlates of HAQ-DI scores > or = 1.0. CONCLUSION: Increased HAQ-DI scores at baseline were correlated with reduced fist closure, reduced hand-spread, elevated platelet count, presence of tender joints, older age, and female sex. The most important contributor to functional impairment was hand dysfunction. Even within the first 18 months after SSc onset, moderate-severe functional impairment (HAQ-DI scores > or = 1.0) was frequent (53%) in this group of diffuse SSc patients. In early diffuse SSc, the self-administered HAQ-DI is therefore a valuable assessment of function that correlates with objective physical and laboratory measures of SSc disease involvement. Abnormal HAQ-DI scores may support patient claims of functional impairment, help to focus physician attention on implementing measures to reduce functional impairment, and be useful in reflecting the disease course over time.

The effect of comorbidity on care seeking for back problems in the United States.

PURPOSE: We assess the effect of comorbidity on self-reported use of health care for back problems in the United States. METHODS: Data from the 1989 National Health Interview Survey (NHIS) were used to perform cross-sectional analyses of adults who reported a back-related condition. The presence of one or more nonback-related conditions (and associated disability and health care) were the primary predictor variables. Weighted logistic regression modeling was performed to estimate odds ratios (ORs) adjusted for the effects of covariates. RESULTS: The 1989 NHIS included 84,572 adults, of which 4790 (5.7%) reported at least one back-related condition. Of these, 931 (19.6%) sought health care for their back condition during the 2-week reference period. Among all adults with reported back problems, those with disabling comorbidities and those who sought care for their comorbidities during the reference period were less likely to have sought back care than were those with no comorbidities. Subjects with back-related disabilities who reported nondisabling comorbidities without associated health care were much more likely to have sought back care than were similar subjects without any comorbidities. CONCLUSIONS: The decision to seek care for a back problem is a complex process that depends upon the presence and impact of other conditions and the use of care for these conditions. Comorbid back problem sufferers may not seek back care when afflicted with other disabling conditions or conditions that may be perceived to be more amenable to care.

Interobserver reliability of detecting lumbar intervertebral disc high-intensity zone on magnetic resonance imaging and association of high-intensity zone with pain and anular disruption.

STUDY DESIGN: Retrospective analysis of a spine imaging center's records of patients with chronic low back pain referred by tertiary care facilities. OBJECTIVES: 1) To assess the interobserver reliability of detecting lumbar intervertebral disc high-intensity zone on T2-weighted magnetic resonance imaging, and 2) to assess the relation between high-intensity zone and discography or post-computed tomography in symptomatic patients with low back pain. SUMMARY OF BACKGROUND DATA: Two of the three previous studies on this subject found an association between high-intensity zone and the presence of Grade 4 anular disruption with discographic reproduction of patients' exact low back pain. METHODS: Records of patients with low back pain who had undergone lumbar spine discography injection and post-computed tomography from June 1995 to August 1996 were reviewed. Two independent observers were asked to identify the presence of an high-intensity zone from the T12-L1 disc to L5-S1 on T2-weighted magnetic resonance images. With this data, interobserver reliability was assessed with the kappa statistic. Concordant high-intensity zone results were then compared with the Dallas Discogram rating for anular disruption and to patients' subjective pain response to discography injection. With this data, the sensitivity, specificity, and predictive values of high-intensity zone for detecting disc disruption and pain response were calculated. RESULTS: The interobserver reliability for detecting a high-intensity zone in a given disc was fair to good (kappa = 0.57; 95% confidence interval = 0.44, 0.70). The sensitivity of high-intensity zone for detecting Grade 4 anular disruption and exact pain was poor (31%) but its specificity was relatively high (90%). The positive predictive value of a high-intensity zone was low (40%) for a severely disrupted and exactly painful disc. CONCLUSIONS: The interobserver reliability of detecting a high-intensity zone and the positive predictive value of the presence of a high-intensity zone for detecting a severely disrupted and exactly painful disc were much lower than previous studies have shown. The relatively low positive predictive value may be attributable to differences in sample characteristics or procedural variations, or suggest that a high-intensity zone is not indicative of exactly painful internal intervertebral disc disruption.

Medical, law, and business students' perceptions of the changing health care system.

An unanswered question in previous research on attitudes to health care systems is whether the values held by medical students are unique to them or simply a cohort phenomenon. This study addresses this by measuring values and attitudes on entry to medical school, and comparing them with two other groups whose academic standing at entry and social status are likely to be comparable business and law students. In this paper four substantive areas are dealt with: managed care, cost controls such as rationing, access to care. and the role of the federal government in regulating health care. There was a high level of agreement between the three groups that society should provide health care to all citizens, and that individuals should have appropriate access. There was also a general preference for being treated in a fee-for-service setting. Some differences were that medical students held more negative views about managed care than some of the others. The students tended to disagree on cost controls, particularly on issues that might impact on their own professions. Medical students were more restrictive than others on concepts of rationing health care and with regard to high tech procedures. Thus the results reflect areas of extensive agreement, but also the fact that even at entry students may differ on issues that are likely to have an economic impact on their careers. The relationship of these attitudes to the changing health care system and to theories about professionalism and the state is discussed.

Congruence between decisions to initiate chiropractic spinal manipulation for low back pain and appropriateness criteria in North America.

BACKGROUND: Recent U.S. practice guidelines recommend spinal manipulation for some patients with low back pain. If followed, these guidelines are likely to increase the number of persons referred for chiropractic care. Concerns have been raised about the appropriate use of chiropractic care, but systematic data are lacking. OBJECTIVE: To determine the appropriateness of chiropractors' decisions to use spinal manipulation for patients with low back pain. DESIGN: Retrospective review of chiropractic office records against preset criteria for appropriateness that were developed from a systematic review of the literature and a nine-member panel of chiropractic and medical specialists. Appropriateness criteria reflect the expected balance between risk and benefit. SETTING: 131 of 185 (71%) chiropractic offices randomly sampled from sites in the United States and Canada. PATIENTS: 10 randomly selected records of patients presenting with low back pain from each office (1310 patients total). MEASUREMENTS: Sociodemographic data on patients and chiropractors; use of health care services by patients; assessment of the decision to initiate spinal manipulation as appropriate, uncertain, or inappropriate. RESULTS: Of the 1310 patients who sought chiropractic care for low back pain, 1088 (83%) had spinal manipulation. For 859 of these patients (79%), records contained data sufficient to determine whether care was congruent with appropriateness criteria. Care was classified as appropriate in 46% of cases, uncertain in 25% of cases, and inappropriate in 29% of cases. Patients who did not undergo spinal manipulation were less likely to have a presentation judged appropriate and were more likely to have a presentation judged inappropriate than were patients who did undergo spinal manipulation (P = 0.01). CONCLUSIONS: The proportion of chiropractic spinal manipulation judged to be congruent with appropriateness criteria is similar to proportions previously described for medical procedures; thus, the findings provide some reassurance about the appropriate application of chiropractic care. However, more than one quarter of patients were treated for indications that were judged inappropriate. The number of inappropriate decisions to use chiropractic spinal manipulation should be decreased.

Immunogenicity of hepatitis B Vaccines. Implications for persons at occupational risk of hepatitis B virus infection.

OBJECTIVE: To assess risk factors for decreased immunogenicity among adults vaccinated with hepatitis B vaccine and to determine the importance of differences in immunogenicity between vaccines among health care workers (HCWs). DESIGN: Randomized clinical trial and decision analysis. PARTICIPANTS: HCSw. MAIN OUTCOME MEASURES: Development of seroprotective levels of antibody to hepatitis B surface antigen (anti-HBs) and the number of expected chronic hepatitis B virus (HBV) infections associated with lack of protection. RESULTS: Overall, 88% of HCWs developed seroprotection. Risk factors associated with failure to develop seroprotection included increasing age, obesity, smoking and male gender (P < .05). Presence of a chronic disease was associated with lack of seroprotection only among persons > or = 40 years of age (P < .05). The two vaccines studied differed in their overall seroprotection rates (90% vs. 86%; P < .05), however, this difference was restricted to persons > or = 40 years of age (87% vs. 81%; P < .01). Among HCWs > or = 40 years of age, the decision analysis found 44 (0.34/100,000 person-years) excess chronic HBV infections over the working life of the cohort associated with use of the less immunogenic vaccine compared to the other. CONCLUSIONS: He patitis B vaccines are highly immunogenic, but have decreased immunogenicity associated with increasing age, obesity, smoking, and male gender; and among older adults, the presence of a chronic disease. One of the two available vaccines is more immunogenic among older adults; however, this finding has little clinical or public health importance. Hepatitis B vaccines should be administered to persons at occupational risk for HBV infection early in their career, preferably while they are still in their training.

Use of chiropractic services from 1985 through 1991 in the United States and Canada.

OBJECTIVES: The purpose of this paper is to describe the demographic and clinical characteristics of chiropractic patients and to document chiropractic visit rates in 6 sites in the United States and Canada. METHODS: Random samples of chiropractors from 5 US sites and 1 Canadian site were selected. A record abstraction system was developed to obtain demographic and clinical data from office charts. RESULTS: Of the 185 eligible chiropractors sampled, 131 (71%) participated. Sixty-eight percent of the selected charts showed that care was sought for low back pain, while 32% recorded care for other reasons. Spinal manipulative therapy was recorded in 83% of all charts. There was a greater than 2-fold difference in the median number of visits related to low back pain per episode of care across sites. The chiropractic visit rates in the US sites and Ontario are estimated to be 101.2 and 140.9 visits per 100 person-years, respectively. CONCLUSIONS: The chiropractic use rate in these sites is twice that of estimates made 15 years ago. The great majority of patients receive care for musculoskeletal conditions of the back and neck. The number of visits per episode varies appreciably by site.

The effects of comorbidity and other factors on medical versus chiropractic care for back problems.

STUDY DESIGN: This study is a cross-sectional analysis of adults in the United States who reported at least one back-related visit to a health care professional during a 2-week reference period. OBJECTIVES: To estimate and compare the effects of comorbidity and other factors on self-reported use of medical and chiropractic care for back problems in the United States. SUMMARY OF BACKGROUND DATA: Although back pain is the second most frequent primary symptom reported by patients seeking medical care and the most frequent primary symptom among chiropractic patients, there is a dearth of research on the predictors of chiropractic and medical care among back pain patients. METHODS: Data from the 1989 National Health Interview Survey were used to perform a cross-sectional analysis of adults who sought care for a back-related condition. The primary predictor variables included comorbidity and associated disability, sociodemographic variables, and back-problem-related variables. Weighted logistic regression modeling was performed to estimate odds ratios adjusted for the effects of covariates. RESULTS: Of the 4790 adults with reported back problems, 931 sought health care for their back condition during the 2-week reference period. Adults with disabling comorbidities and back-related restricted-activity days were relatively less likely to use chiropractic care than primary medical care. Those who were male, high-school educated, single, employed, and with more than nine doctor visits during the previous 12 months were relatively more likely to use chiropractic care than primary medical care. CONCLUSIONS: The presence of comorbidity-related or back-related disability, as well as other factors, affect the type of care sought for back conditions among adults in the United States.

Use of acupuncture by American physicians.

OBJECTIVES: Little is known about the characteristics of American physicians who currently practice acupuncture. We asked: (1) Do the demographics of physicians practicing acupuncture differ from the general physician population? (2) Do these physicians use or endorse other alternative therapies? (3) For which conditions is acupuncture most commonly used? (4) For which conditions is acupuncture perceived to be most efficacious? DESIGN: Mailed survey of physicians who incorporate acupuncture into their practice. PARTICIPANTS: Membership of the American Academy of Medical Acupuncture (AAMA). OUTCOME MEASURES: Demographic information regarding physicians and practice characteristics; specific illnesses treated, and perceived efficacy; use of other complementary modalities; personal reasons for practicing acupuncture. RESULTS: Compared with national data, respondents were more likely to be nonspecialists, in private practice, and age 35 to 54. There was an equal proportion of men and women. Most had been doing acupuncture for < 5 years; most use it on < 25% of their patients. Endorsement or use of other complementary methods (spinal manipulation, herbal medicine, supplements, homeopathy) was common. Acupuncture was more commonly used for pain conditions than general medical problems or addiction management. Reasons for use included: efficacy of the technique, an alternative in cases of inadequacy of standard medical approach, and a multidimensional approach to health care. CONCLUSIONS: Physicians surveyed in this study who incorporate acupuncture into their practice do so mainly to treat pain problems. They are more likely to be in the 35 to 54 age group, nonspecialists, and in private practice when compared with national averages. These physicians are also more likely to use or endorse other complementary modalities.