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Mortality and malnutrition among populations living in South Darfur, Sudan: results of 3 surveys, September 2004.

CONTEXT: Mass violence against civilians in the west of Sudan has resulted in the displacement of more than 1.5 million people (25% of the population of the Darfur region). Most of these people are camped in 142 settlements. There has been increasing international concern about the health status of the displaced population. OBJECTIVE: To perform rapid epidemiological assessments of mortality and nutritional status at 3 sites in South Darfur for relief efforts. DESIGN, SETTING, AND PARTICIPANTS: In August and September 2004, mortality surveys were conducted among 137,000 internally displaced persons (IDPs) in 3 sites in South Darfur (Kass [n = 900 households], Kalma [n = 893 households], and Muhajiria [n = 900 households]). A nutritional survey was performed concomitantly among children aged 6 to 59 months using weight for height as an index of acute malnutrition (Kass [n = 894], Kalma [n = 888], and Muhajiria [n = 896]). A questionnaire detailing access to food and basic services was administered to a subset of households (n = 210 in each site). MAIN OUTCOME MEASURES: Crude and under 5-year mortality rates and nutritional status of IDPs in Kass, Kalma, and Muhajiria, South Darfur. RESULTS: Crude mortality rates, expressed as deaths per 10,000 per day, were 3.2 (95% confidence interval [CI], 2.2-4.1) in Kass, 2.0 (95% CI, 1.3-2.7) in Kalma, and 2.3 (95% CI, 1.2-3.4) in Muhajiria. Under 5-year mortality rates were 5.9 (95% CI, 3.8-8.0) in Kass, 3.5 (95% CI, 1.5-5.7) in Kalma, and 1.0 (95% CI, 0.03-1.9) in Muhajiria. During the period of displacement covered by our survey in Muhajiria, violence was reported to be responsible for 72% of deaths, mainly among young men. Diarrheal disease was reported to cause between 25% and 47% of deaths in camp residents and mainly affected the youngest and oldest age groups. Acute malnutrition was common, affecting 14.1% of the target population in Kass, 23.6% in Kalma, and 10.7% in Muhajiria. CONCLUSION: This study provides epidemiological evidence of the high rates of mortality and malnutrition among the displaced population in South Darfur and reinforces the need to mount appropriate and timely humanitarian responses.

Adolescent↗

[Quality of life assessment of cataract surgery in elderly population of Doumen County, Guangzhou Province].

OBJECTIVE: To evaluate the outcome of cataract surgery in elderly population in Doumen County, Guangdong Province by assessment of subjective visual function and quality of life. METHODS: All the cataract postoperative subjects were identified in the population-level. Visual Function and Quality of Life (VF/QOL) questionnaire developed by National Eye Institute, USA in developing countries was used as the instrument. This Questionnaire was administered by four trained-interviewers in all subjects with visual acuity less than 0.1 in either eye (treated as visual impairment cases), One in every 20 persons with visual acuity better than 0.3 (treated as normal control cases) in both eyes (un-operated group) and all cataract postoperative cases (operated group). RESULTS: In 5 342 cross-sectional examined persons, individuals who could be successfully interviewed included 99 (90.8%) cataract postoperative cases, 535 (85.5%) visual impairment cases and 119 normal control ones. On a 0 - 100 scale, medium total scores of VF and QOL diminished from 92 to 2 and from 100 to 19 respectively along with visual status from normal to severe blindness in the un-operated group. Similar findings on visual status and VF/QOL scores were found in the operated group. The overall scores of VF and QOL were 40 and 56 for operated one and 56 and 72 for un-operated one. After adjusted the confounding effect of visual status, age, sex and education by multivariate regression model, the difference of QOL scores between un-operated and operated group was significant (P = 0.015), while no significant difference (P = 0.199) was found in VF scores. CONCLUSIONS: The scores of VF and QOL are significantly correlated with the visual status. Subjective visual function and quality of life could not be significantly improved after cataract surgery in this target population. Concerns should be paid in postoperative follow-up, aphakic correction and social-psychological rehabilitation.

Aged↗

Malignant transformation of human fibroblast cell strain MSU-1.1 by N-methyl-N-nitrosourea: evidence of elimination of p53 by homologous recombination.

To determine whether N-methyl-N-nitrosourea (MNU) can induce malignant transformation of human fibroblasts and whether O6-methylguanine (O6-MeG) is involved, two populations of infinite life span cell strain MISU-1.1, differing only in level of O6-alkylguanine-DNA alkyltransferase, were treated with MNU and assayed for focus formation. MNU caused a dose-dependent increase in the frequency of foci in both groups, but the dose required was significantly lower in the cells lacking O6-alkylguanine-DNA alkyltransferase, indicating that O6-MeG was causally involved. Of 35 independent focus-derived strains assayed for p53 transactivating abilily, one was heterozygous, and 15 had lost all activity, 1 of 7 from untreated cells and 14 of 27 from MNU-treated cells. These results indicate that loss of p53 is not required for focus formation but may permit cells to form foci. Of 35 strains assayed for tumorigenicity, 10 formed malignant tumors with a short latency, all 10 lacked wild-type p53. The p53 heterozygous strain also formed tumors after a long latency, and the cells from those tumors lacked p53 transactivating ability. None of the 19 strains with wild-type p53 formed tumors. These results indicate that although loss of p53 is not sufficient for malignant transformation of MSU-1.1 cells, it may be necessary. Analysis of the p53 cDNA from several focus-derived strains lacking p53 activity revealed that each contained the same mutation, an A to G transition at codon 215, resulting in a change from serine to glycine. Because p53 can be inactivated by mutations at any one of a large number of sites, finding the same mutation in each strain assayed strongly suggests that the target population included a subpopulation of cells with this codon 215 mutation in one allele. Further analysis showed that all 15 focus-derived cells strains that lacked p53 transactivating activity contained two alleles, each with the same codon 215 mutation, and that the mutant allele in the heterozygous strain also had that mutatation. Analysis of the p arm of chromosome 17 of the focus-derived cell strains containing the codon 215 mutation revealed seven patterns of loss of heterozygosity, evidence of mitotic homologous recombination. Similar analysis of a separate series of cell strains, derived from foci induced by cobalt-60, revealed four patterns of loss of heterozygosity, only two of which had been found with those induced by MNU. These data suggest that homologous mitotic recombination, induced by O6-MeG in a subpopulation of cells heterozygous for p53 mutation, rendered the cells homozygous for loss of p53 activity, that this allowed the cells to form foci, and that although loss of p53 is not sufficient for malignant transformation, it predisposes cells to acquire the additional changes needed for such transformation.

Alleles↗

Trends in breast cancer screening in Missouri from 1987 to 1995, and predictions for the years 2000 and 2010.

BACKGROUND: Breast cancer is a major cause of morbidity and mortality in the United States (U.S.) and Missouri. In 1992, 3,915 new breast cancer cases were diagnosed and in 1995, 1,006 deaths from breast cancer were reported in Missouri. Although breast cancer incidence has increased in Missouri in the past 20 years, there are indications that early detection has also increased during the same period. Knowledge about which segments of the population have experienced the greatest increase in mammography screening rates helps in planning and implementation of breast cancer control programs at the state level. OBJECTIVES: Examine the prevalence and trends of lifetime mammography and 2-year mammography compliance in Missouri by age, race, and education from 1987 to 1995 and make predictions for the years 2000 and 2010. METHODS: We used data from the Missouri Behavioral Risk Factor Surveillance System (BRFSS), 1987 to 1995, to estimate the prevalence of ever having had a mammogram and compliance with mammography screening guidelines within two years by race, age, and education status among Missouri women over age 18. Using linear models, we regressed breast cancer screening prevalence estimates on time to obtain trends and predictions. RESULTS: Overall, African-American women were more likely to have had a lifetime mammogram than white women. However, we found a steady increase in the prevalence of ever having had a mammogram for all groups of women defined by age and education status, except among African Americans. Increase in the prevalence of ever having had a mammogram was much higher in women age 50 and older and slightly higher among women with a high school education or less. The average prevalence of 2-year mammography screening compliance was about 60% for all groups, a rate which did not significantly change between 1987 and 1995. By the year 2000, white women will have mammography rates equal to or higher than African-American women, and the majority of all women age 50 and older (98.3% to 100%) will have had a lifetime mammogram. CONCLUSION: Missouri target populations are predicted to attain Year 2000 National Health Objectives concerning lifetime mammography. Current efforts should be continued in order to maintain levels of mammography, particularly among African-American women.

Adolescent↗

Evaluation of the influence of breathing on the movement and modeling of lung tumors.

PURPOSE: Respiration causes movement and potential shape change in lung tumors that are not fully appreciated using conventional free-breathing CT models for radiotherapy planning. Although target expansion has the potential to ensure proper tumor coverage in the face of motion on a free-breathing CT scan, large variations in how individual patients' tumors move may make such expansions difficult to uniformly define. In addition, excessive expansion may result in the unnecessary inclusion of normal lung in the treated volume. This study was designed to evaluate the influence of breathing movement on tumors and to assess the validity of the free-breathing CT scan for target delineation in the lung. METHODS AND MATERIALS: Data from 16 consecutive lung cancer patients who underwent treatment planning CT scans at inhale and exhale and during free breathing on a fast helical CT scanner were analyzed. Gross tumor volumes (GTV) were defined on each scan. A composite GTV was created by combining the inhale and exhale GTVs (COMP). Two methods of expansion were used to compare COMP to the free-breathing GTV (FREE). First the free-breathing data set was expanded uniformly by 1 cm (FREE + 1). Next, a nonuniform expansion was generated in all 6 directions to ensure complete coverage of COMP with the minimal subtended volume (FREE + EXP). The amount of excess normal lung treated with these 2 expansions was compared. The volume of the COMP missed using the 1-cm expansion was determined. RESULTS: There was a significant amount of excess normal lung tissue treated with the uniform 1-cm (FREE + 1) expansion, as well as with the nonuniform (FREE + EXP) expansion. In addition, there were also cases where this technique led to marginal miss of the tumor, including one case where 47% of the overall tumor was missed with this 1-cm (FREE + 1) expansion. An attempt to create a systematic model for expansion was not successful. Although the mean expansions in the anterior-posterior, superior-inferior, and right-left directions were reasonable (0.9, 1.0, and 0.8 cm, respectively), the large intrapatient variations (sigma 0.6 cm anterior-posterior, 0.7 cm superior-inferior, and 0.5 cm right-left) suggest difficulty in assigning a simple rule for population target expansion. Some extension of FREE outside of the borders of COMP was observed, suggesting the need for evaluation of reproducibility over multiple breathing states. CONCLUSIONS: Traditional methods of expanding the GTV to CTV by 1 cm are less than ideal. This method tends to include more normal lung than necessary and may lead to marginal miss. Interpatient tumor movement variations further prohibit defining a simple rule for nonuniform expansion that would minimize the volume of normal lung in the target. Although the development of target volumes by combining information from breath-hold CT scans at inhale and exhale states shows some promise in minimizing excess lung irradiated while maintaining adequate tumor coverage, further tests of breathing reproducibility need to be performed to provide a confident baseline for defining target expansions by this technique.

Adult↗

A randomised controlled trial and cost effectiveness study of systematic screening (targeted and total population screening) versus routine practice for the detection of atrial fibrillation in the over 65s: (SAFE) [ISRCTN19633732].

BACKGROUND: Atrial fibrillation (AF) has been recognised as an important independent risk factor for thromboembolic disease, particularly stroke for which it provides a five-fold increase in risk. This study aimed to determine the baseline prevalence and the incidence of AF based on a variety of screening strategies and in doing so to evaluate the incremental cost-effectiveness of different screening strategies, including targeted or whole population screening, compared with routine clinical practice, for detection of AF in people aged 65 and over. The value of clinical assessment and echocardiography as additional methods of risk stratification for thromboembolic disease in patients with AF were also evaluated. METHODS: The study design was a multi-centre randomised controlled trial with a study population of patients aged 65 and over from 50 General Practices in the West Midlands. These purposefully selected general practices were randomly allocated to 25 intervention practices and 25 control practices. GPs and practice nurses within the intervention practices received education on the importance of AF detection and ECG interpretation. Patients in the intervention practices were randomly allocated to systematic (n = 5000) or opportunistic screening (n = 5000). Prospective identification of pre-existing risk factors for AF within the screened population enabled comparison between high risk targeted screening and total population screening. AF detection rates in systematically screened and opportunistically screened populations in the intervention practices were compared to AF detection rate in 5,000 patients in the control practices.

Aged↗

Homocysteine levels in men and women of different ethnic and cultural background living in England.

This population-based cross-sectional study in South London looks at the total homocysteine (tHcy) levels in groups of different ethnic background and the possible role of environmental factors and the 677C-->T genetic polymorphism of the methylenetetrahydrofolate reductase (MTHFR). Fasting plasma tHcy was measured in 1392 men and women, age 40-59 years; 475 were white, 465 of African origin (of whom 180 were West Africans and 280 Caribbeans) and 452 South Asian (of whom 222 were Hindus and 167 Muslims). The homozygous MTHFR TT variant had observed frequencies of 0.10 in whites, 0.01 in people of African origin and 0.02 in South Asians (P<0.001). tHcy levels were 16% (95% CI 8-26) higher amongst TT than CC. tHcy levels were 25% (21-29) higher in men than women. Levels were significantly higher in South Asians than whites (8% [3-13]). Vegetarians had higher levels than non-vegetarians (25% [18-33]). These differences were present after adjustments for age, sex, smoking, body mass index (BMI), MTHFR 677C-->T polymorphism and socio-economic status. Compared with whites (10.0 [9.7-10.3] micromol/l), and allowing for confounders, Hindus had significantly higher levels of tHcy (12.1 [11.6-12.6] micromol/l). This difference was attenuated by the inclusion of vegetarianism in the model (11.3 [10.8-11.9] micromol/l). In contrast Muslims had similar tHcy levels to whites while both West Africans and Caribbeans had slightly lower levels, though differences were not significant. The reported higher levels of tHcy in South Asians are due to high levels amongst Hindus only. They are in part accounted for by their vegetarianism. These differences in tHcy are large enough to be important contributors to the risk of vascular disease and may be preventable by simple targeted population strategies.

Adult↗

Increasing practice nurse access to alcohol training.

Policy makers have repeatedly placed emphasis on the role of primary care in screening for at-risk alcohol consumption and delivering public health messages to the general population. Research has pointed to primary care staff holding negative attitudes towards alcohol misusing patients. Training has traditionally been seen as the key to increasing the capacity of the medical field to engage with alcohol misusing patients but little work has been undertaken to examine the potential barriers to training take up. Consequently, the aim of this study was to explore the willingness of practice nurses to be trained in alcohol screening and brief intervention, and whether identifiable barriers to training exist and how they may be overcome. All practice nurses (n = 82) in an outer London (UK) Health Authority Area were twice mailed an invitation to an alcohol training seminar and a telephone invitation was made to all of those who did not reply to the mailings. Those who did not attend (n = 66) were contacted to take part in a short structured telephone interview - 89% (59/66) were contacted successfully and interviewed. Respondents were experienced in primary care and viewed health promotional activity as a valid part of their role. Few had undertaken previous alcohol training and as a group they were highly active in attending training events with training undertaken tending to be related directly to perceived practice needs and priorities: thus this group could not be characterized as unwilling to be trained. Barriers to training at alcohol events were found to be either personal or work-related, with most nurses interested in receiving further training or information. These data imply that the ways in which training is organized and delivered require sensitivity to identifiable barriers if it is to reach and effect changing practice among practice nurses successfully. A range of possibilities are identified as alternative approaches to the provision of elective training events which may be more acceptable to the target population of health-care staff.

Adult↗

Focused screening for occult carotid artery disease: patients with known heart disease are at high risk.

OBJECTIVES: Stroke puts a major financial burden on our healthcare system. However, carotid duplex scanning performed as a screening test for occult carotid artery stenosis (CAS) currently is not reimbursed by Medicare. The goals of this study were to develop a cost-effective stroke screening program, to determine the prevalence of potential causes of stroke in this population, and to define a population at high risk in which screening would be most effective. METHODS: In a community-based stroke screening program, patients were eligible if they were older than 60 years and had a history of either hypertension, heart disease, or cigarette smoking, or a family history of stroke. Screening included blood pressure determination, an electrocardiographic rhythm strip, and a previously validated modified carotid duplex ultrasound examination to detect CAS 50% or greater. The relationships between standard demographic risk factors and screening outcomes were analyzed. RESULTS: Screening was performed in 610 patients. Unilateral or bilateral CAS was detected in 66 patients (10.8%). The finding of occult CAS was more prevalent than that of new hypertension (2.6%) or new atrial fibrillation (0.5%). Patients with known hypertension were significantly more likely to have CAS than were those without hypertension (12.7% vs 7.8%; P =.05). Patients with heart disease were significantly more likely to have CAS than were those without heart disease (18.2% vs 8%; P <.0001). Patients with both risk factors were significantly more likely to have occult carotid artery disease than were patients without either risk factor (22.1% vs 8.5%; P <.0001). Multivariate analysis with logistic regression revealed a history of heart disease as an independent predictor of occult carotid artery disease (odds ratio 95% confidence interval, 1.4-4.4). Type of heart disease was not a significant factor in predicting occult CAS. Direct cost of the screening, including community outreach, nurses, technicians, support staff, and miscellaneous expenses, was less than $75 per patient. CONCLUSIONS: In a screening program for treatable causes of potential stroke, CAS was the most commonly diagnosed disease. More than one of every five patients with known hypertension and heart disease had occult CAS. Known heart disease of any type was a significant independent predictor of occult CAS. Screening for treatable causes of potential stroke can be cost-effective. This information could help to further target populations to screen for occult CAS and to justify reimbursement for screening carotid duplex scanning examinations.

Aged↗

Predischarge screening of very low birthweight infants by click evoked otoacoustic emissions.

OBJECTIVE: To evaluate the role of transient evoked otoacoustic emission (TEOAE) in screening very low birthweight (VLBW) neonatal intensive care unit (NICU) graduates for hearing loss in comparison with visual reinforcement orientation audiology (VROA) at 10 months. METHODOLOGY: The study population was all VLBW neonatal survivors discharged from a single regional NICU at John Hunter Childrens Hospital (JHCH), Newcastle, New South Wales, Australia, between April 1994 and March 1996. A TEOAE screen was performed prior to discharge and repeated if necessary until a pass was obtained in at least one ear. Infants were further screened by VROA at their local Australian Hearing Services (AHS) office at 10 months corrected age. Repeated TEOAE failures were referred directly for an ENT opinion. RESULTS: A total of 193 infants were eligible for enrolment during the study period. One hundred and forty-four (75%) received TEOAE testing. The median age of first screen was 36 weeks gestational age. Ninety-five (66%) of infants tested passed on a single screen. Of the remaining 49 infants, 26 passed on retesting (overall pass rate 84%). Twenty-three (16%) were deemed to have failed the TEOAE screen. Of the 121 infants who passed TEOAE, only 67 (55%) completed VROA. Two of these infants have a high frequency sensorineural loss and one of them has been aided. In the 23 who failed TEOAE, nine have subsequently had normal VROA, another, though not tested is clinically normal. three have hearing loss with middle ear disease and eight have confirmed sensorineural deafness, all aided. One infant has died and an infant with Down's syndrome has been adopted out of the area. It is of interest to note that the eight aided infants are all of less than 28 weeks gestation. If we restrict analysis to infants with completed VROA testing, the TEOAE has a 97% negative predictive value for sensorineural deafness and a 38% positive predictive value. CONCLUSIONS: This study has highlighted both the prevalence of hearing impairment in the very premature survivors and difficulties in compliance with a VROA based hearing screen. We see an advantage in directing resources towards an early screening test, such as TEOAE, that can be applied while the target population is still captive.

Audiometry, Evoked Response↗

Promotion of folate for the prevention of neural tube defects: who benefits?

Since the publication of randomised trials showing firm evidence of prevention of neural tube defects with periconceptional folic acid, there have been population health promotion programmes to encourage women to take folic acid supplements, and the introduction of voluntary fortification of some foods with folic acid in Australia. In order to evaluate these two strategies, we collected data by self-administered questionnaire from a random sample of recently pregnant women in Western Australia between September 1997 and March 2000. Response to health promotion was measured in three ways: (1) knowledge of the association between periconceptional folate and prevention of spina bifida (the 'correct message'); (2) use of periconceptional vitamin supplements of folic acid daily in the periconceptional period; and (3) daily folate intake from fortified foods in the 6 months before pregnancy. We examined the relationship of maternal demographic and behavioural characteristics with these three measures. Overall, 62.3% of women were aware of the correct message before pregnancy, 28.5% reported taking 200 microg or more of folic acid from supplements daily in the periconceptional period and 56.6% of women obtained 100 microg or more of folic acid from fortified foods. Women who first became aware of the correct message during pregnancy or who were unaware of the correct message before or during pregnancy were more likely than women aware before pregnancy to be younger, having their first pregnancy, be single or in a de facto relationship, have no tertiary education, and be a public patient. Similar associations were seen for women taking either no folic acid or < 200 microg of folic acid in supplements daily in the periconceptional period. There were no significant associations between these demographic variables and amount of folate obtained from fortified foods. Women who were unaware of the correct message and did not take folic acid supplements were more likely to have smoked, not to have engaged in exercise, and not to have planned their pregnancy, whereas there was no association with these behavioural characteristics and intake of folate from fortified foods. These results indicate that health promotion strategies have not reached all segments of the target population equally, but there is no such disparity with folate-fortified foods, and they suggest that mandatory fortification of a staple food is likely to reach all women regardless of demographic and behavioural characteristics, and hence provide improved opportunity for prevention of neural tube defects in Australia.

Adult↗

Effects of clopidogrel and aspirin combination versus aspirin alone on platelet aggregation and major receptor expression in patients with heart failure: the Plavix Use for Treatment Of Congestive Heart Failure (PLUTO-CHF) trial.

BACKGROUND: Persistent platelet activation may contribute to thrombotic events in patients with congestive heart failure (CHF). Chronic use of mild platelet inhibitors could therefore represent an independent avenue to improve morbidity, mortality, and quality of life in this expanding population. Although clopidogrel is widely used in patients with acute coronary syndromes and ischemic stroke, the ability of this novel ADP-receptor antagonist to inhibit platelet function in patients with CHF is unknown. We assessed antiplatelet properties of clopidogrel with aspirin (C+A) versus aspirin alone (A) in patients with CHF with heightened platelet activity. METHODS: Patients with left ventricular ejection fraction <40%, or CHF symptoms in the setting of preserved systolic function and New York Heart Association class II-IV were screened. Patients were considered to have platelet activation when 4 of the following 5 parameters were met: ADP-induced platelet aggregation >60%; collagen-induced aggregation >70%; whole blood aggregation >18 ohms; expression of GP IIb/IIIa >220 log MFI; and P-selectin cell positivity >8%. All patients were treated with 325 mg of acetylsalycilic acid (ASA) for at least 1 month. Patients receiving an antithrombotic agent other than ASA were excluded. Patients meeting clinical and laboratory criteria were randomly assigned to C+A (n=25), A (n=25) groups, or represent screen failures (n=38). Platelet studies (conventional and whole blood aggregometry, shear-induced activation, expression of 10 major receptors and formation of platelet-leukocyte microparticles) were performed at baseline and after 30 days of therapy. RESULTS: There were no deaths, hospitalizations, or serious adverse events. There were no changes in platelet parameters in the A group. In contrast, therapy with C+A resulted in a significant inhibition of platelet activity assessed by ADP-induced (P =.00001), and epinephrine-induced (P =.0016) aggregation, closure time (P =.04), expression of PECAM-1 (P =.009), GP Ib (P =.006), GP IIb/IIIa antigen (P =.0001), GP IIb/IIIa activity with PAC-1 (P =.0021), and CD151 (P =.0026) when compared with the A group. Therapy with C+A also resulted in the reduced formation of platelet-leukocyte microparticles (P =.021). Collagen-induced aggregation in plasma and in whole blood, expression of vitronectin receptor, P-selectin, CD63, CD107a, and CD107b did not differ among groups. CONCLUSIONS: Treatment with C+A for 1 month provides significantly greater inhibition of platelet activity than ASA alone in patients with CHF. Patients with CHF with heightened platelet activity represent a potential target population in which addition of clopidogrel may decrease mortality rates by reducing the incidence of thrombotic vascular events.

Aged↗

Estimation of "needs" and "probable uptake" for HIV/AIDS preventive vaccines based on possible policies and likely acceptance (a WHO/UNAIDS/IAVI study).

Once an effective HIV vaccine is discovered, a major challenge will be to ensure its world wide access. A preventive vaccine with low or moderate efficacy (30-50%) could be a valuable prevention tool, especially if targeted to populations at higher risk of HIV infection. High efficacy vaccines (80-90%) could be used in larger segments of the population. Estimated "needs" for future HIV vaccines were based on anticipated policies regarding target populations. Estimated "needs" were adjusted for "accessibility" and "acceptability" in the target populations, to arrive at an estimate of "probable uptake", i.e. courses of vaccine likely to be delivered. With a high efficacy vaccine, global needs are in the order of 690 million full immunization courses, targeting 22 and 69%, respectively, of the 15-49 years old, world wide and in sub-Saharan Africa, respectively. With a low/moderate efficacy vaccine targeted to populations at higher risk of HIV infection, the global needs were estimated to be 260 million full immunization courses, targeting 8 and 41%, respectively, of the world and sub-Saharan African population aged 15-49 years. The current estimate of probable uptake for hypothetical HIV vaccines, using existing health services and delivery systems, was 38% of the estimated need for a high efficacy vaccine, and 19% for a low/moderate efficacy vaccine. Bridging the gap between the estimated needs and the probable uptake for HIV vaccines will represent a major public health challenge for the future. The potential advantages and disadvantages of targeted versus universal vaccination will have to be considered.

AIDS Vaccines↗

Osteoporosis follow-up after wrist fractures following minor trauma.

BACKGROUND: Patients presenting with low-trauma wrist fractures are an ideal target population for early case finding of osteoporosis. We decided to investigate whether this early detection occurred in practice. METHODS: This study was conducted at a single center in Edmonton, Alberta. A structured interview format was used to contact 112 (72%) of 156 patients older than 40 years who were diagnosed as having an atraumatic fracture of the distal radius/ulna from April 1997 to March 1998 and from January 1999 to February 1999. Information on osteoporosis follow-up and drug therapy was obtained from the patient. RESULTS: The time between fracture and telephone interview ranged from 6 months to 3 years, with the majority of the sample being interviewed at least 1 year after fracture. Of the 112 patients in this study, 44 had sustained previous fractures, 17 of which had occurred at the wrist, vertebrae, or hip. Sixteen patients in the sample had already sustained a subsequent clinical fracture before our telephone contact. Thirty-two patients had received treatment for osteoporosis before fracture. A further 24 patients (21%) had undergone osteoporosis follow-up after fracture. After fracture, 42 (38%) of all patients were receiving either hormone replacement therapy or using a bisphosphonate. CONCLUSIONS: Only 50% of the study population had received osteoporosis follow-up after fracture. Few patients had any change in their medication use after fracture. The findings in this study population suggest that recognition of the potential for osteoporosis in such patients is inadequate. Given the magnitude of this public health care problem, it is clear that attention to case finding and treatment of osteoporosis should be increased.

Age Distribution↗

Pneumococcal vaccination: analysis of opportunities in an inner-city hospital.

BACKGROUND: Adult pneumococcal vaccination rates for persons at risk of developing pneumococcal disease remain below desired levels. Various sites within the hospital (inpatient medicine wards [IMWs], general medicine clinics [GMCs], and emergency departments [EDs]) have been suggested as venues for administering vaccination. The cost-effectiveness of such sites for delivery of pneumococcal vaccination is not known. OBJECTIVE: To compare the potential coverage of at-risk patients and cost of pneumococcal vaccination delivered in an ED, GMC, and IMWs. METHODS: We studied a retrospective cohort of 300 patients with pneumococcal bacteremia who had been hospitalized at Cook County Hospital, an inner-city Chicago public teaching hospital, from January 1994 through December 1998. We measured the presence of risk factors, as defined by the Centers for Disease Control and Prevention, for developing pneumococcal disease prior to index admission for bacteremia; patient use of ED, GMC, and IMWs from 4 weeks to 5 years before index admission; size of target population for vaccination in each site; and cost benefit of a pneumococcal vaccination strategy at each site. RESULTS: In the 4 weeks to 5 years before index admission, risk factors were present in 209 patients; 182 (87.1%) of the 209 had been in the ED, 104 (49.7%) in an IMW, and 64 (30.6%) in a GMC. The ED showed the greatest potential vaccine coverage, at a cost savings in a best-case scenario; the IMWs showed the best cost-benefit ratio but would provide access to fewer at-risk patients; and a program in the GMC would reach the fewest at-risk patients, with a cost-benefit ratio similar to that of the ED. CONCLUSIONS: The ED in an inner-city hospital has the potential to vaccinate more patients at risk of pneumococcal bacteremia than a GMC or IMWs, and may do so at a cost savings. A prospective evaluation of such a strategy is warranted.

Adolescent↗

Prophylaxis for human immunodeficiency virus-related Pneumocystis carinii pneumonia: using simulation modeling to inform clinical guidelines.

BACKGROUND: Human immunodeficiency virus (HIV)-infected patients receiving highly active antiretroviral therapy (HAART) have experienced a dramatic decrease in Pneumocystis carinii pneumonia (PCP), necessitating reassessment of clinical guidelines for prophylaxis. METHODS: A simulation model of HIV infection was used to estimate the lifetime costs and quality-adjusted life expectancy (QALE) for alternative CD4 cell count criteria for stopping primary PCP prophylaxis in patients with CD4 cell count increases receiving HAART and alternative agents for second-line PCP prophylaxis in those intolerant of trimethoprim-sulfamethoxazole (TMP/SMX). The target population was a cohort of HIV-infected patients in the United States with initial CD4 cell counts of 350/microL who began PCP prophylaxis after their first measured CD4 lymphocyte count less than 200/microL. Data were from randomized controlled trials and other published literature. RESULTS: For patients with CD4 cell count increases during HAART, waiting to stop prophylaxis until the first observed CD4 cell count was greater than 300/microL prevented 9 additional cases per 1000 patients and cost $9400 per quality-adjusted life year (QALY) gained compared with stopping prophylaxis at 200/microL. For patients intolerant of TMP/SMX, using dapsone increased QALE by 2.7 months and cost $4500 per QALY compared with no prophylaxis. Using atovaquone rather than dapsone provided only 3 days of additional QALE and cost more than $1.5 million per QALY. CONCLUSIONS: Delaying discontinuation of PCP prophylaxis until the first observed CD4 cell count greater than 300/microL is cost-effective and provides an explicit "PCP prophylaxis stopping criterion." In TMP/SMX-intolerant patients, dapsone is more cost-effective than atovaquone.

AIDS-Related Opportunistic Infections↗

Cost-effectiveness of continuous positive airway pressure therapy for moderate to severe obstructive sleep apnea/hypopnea.

BACKGROUND: Obstructive sleep apnea/hypopnea (OSAH) is a common disorder characterized by recurrent collapse of the upper airway during sleep, and is associated with an increased risk of motor vehicle crashes (MVCs). Common first-line therapy for OSAH is continuous positive airway pressure (CPAP). We assessed the cost-effectiveness of CPAP therapy vs none for the treatment of OSAH. METHODS: We used a 5-year Markov model that considers the costs and quality-of-life improvements of CPAP therapy, accounting for the gains from reduced MVC rates. Utility values were obtained from published studies. The MVC rates under the CPAP and no-CPAP scenarios were calculated from National Highway Traffic Safety Administration data and a systematic review of published studies. Costs of MVCs, equipment, and physicians were obtained from US Medicare and the National Highway Traffic Safety Administration. The target population included male and female patients aged 25 to 54 years and newly diagnosed as having moderate to severe OSAH. We examined the findings from the perspectives of a third-party payer and society. RESULTS: From a third-party payer or a societal perspective, CPAP therapy was more effective but more costly than no CPAP, with incremental cost-effectiveness ratios of $3354 or $314 per quality-adjusted life-year gained, respectively. The incremental cost-effectiveness ratio estimate was most dependent on viewpoint (varying more than 10-fold between societal and third-party payer perspectives) and choice of utility measurement method (varying more than 5-fold between the use of standard gamble and EuroQol 5D utility assessment values). CONCLUSION: When quality of life, costs of therapy, and MVC outcomes are considered, CPAP therapy for patients with OSAH is economically attractive.

Adult↗

Meta-analysis of the sensitivity and specificity of platform posturography.

OBJECTIVE: To compare the sensitivity and specificity of platform posturography with other vestibular tests for patients with peripheral vestibular deficits (PVD), Meniere's disease, benign paroxysmal positional vertigo (BPPV), and central nervous system-vestibular impairment (CNS). DATA SOURCES: A computed search was conducted using the Index Medicus database (1966-1994) and Current Contents Science Editions. STUDY SELECTION: Studies were selected for analysis if the article addressed the sensitivity and/or specificity of platform posturography, compared posturography with another objective test of vestibular function, identified the basis for abnormal test results, and reported the data with sufficient detail to calculate an effect size from a 2 x 2 contingency table. DATA EXTRACTION: A count of the normal and abnormal test results for posturography and the criterion standard were retrieved from each article, analyzed using a chi 2 statistic, and converted to an effect size. A positive effect size indicated that posturography identified abnormalities in patients who had normal tests on the criterion standard. DATA SYNTHESIS: Sensitivity and specificity of posturography were about 50%. The overall effect size was small (0.13) but positive. The diagnostic category had a significant influence on the predictive value of abnormal results (73% for Meniere's disease and BPPV, compared with 41% for PVD, and 44% for mixed CNS and PVD (F2,12 = 5.26, P = .02) and on the magnitude of the effect size (0.41 for mixed CNS and PVD compared with 0.22 for Meniere's disease and BPPV, and -0.10 for PVD (F2,12 = 13.95, P = .001). CONCLUSIONS: Platform posturography provides a measurable supplement to the standard vestibular examination. The enhancement was most notable when the target population included patients with CNS deficits.

Abstracting and Indexing↗