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Abd Alhadi M, Friedman LM, Karlsson EA, Cohen-Lavi L, Burkovitz A, Schultz-Cherry S, Noah TL, Weir SS, Shulman LM, Beck MA, Hertz T. Obesity Is Associated with an Impaired Baseline Repertoire of Anti-Influenza Virus Antibodies. Microbiol Spectr 2023; 11:e0001023. [PMID: 37098954 PMCID: PMC10269616 DOI: 10.1128/spectrum.00010-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2023] [Accepted: 03/27/2023] [Indexed: 04/27/2023] Open
Abstract
Obesity is a risk factor for severe disease and mortality for both influenza and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. While previous studies show that individuals with obesity generate antibody responses following influenza vaccination, infection rates within the obese group were twice as high as those in the healthy-weight group. The repertoire of antibodies raised against influenza viruses following previous vaccinations and/or natural exposures is referred to here as baseline immune history (BIH). To investigate the hypothesis that obesity impacts immune memory to infections and vaccines, we profiled the BIH of obese and healthy-weight adults vaccinated with the 2010-2011 seasonal influenza vaccine in response to conformational and linear antigens. Despite the extensive heterogeneity of the BIH profiles in both groups, there were striking differences between obese and healthy subjects, especially with regard to A/H1N1 strains and the 2009 pandemic virus (Cal09). Individuals with obesity had lower IgG and IgA magnitude and breadth for a panel of A/H1N1 whole viruses and hemagglutinin proteins from 1933 to 2009 but increased IgG magnitude and breadth for linear peptides from the Cal09 H1 and N1 proteins. Age was also associated with A/H1N1 BIH, with young individuals with obesity being more likely to have reduced A/H1N1 BIH. We found that individuals with low IgG BIH had significantly lower neutralizing antibody titers than individuals with high IgG BIH. Taken together, our findings suggest that increased susceptibility of obese participants to influenza infection may be mediated in part by obesity-associated differences in the memory B-cell repertoire, which cannot be ameliorated by current seasonal vaccination regimens. Overall, these data have vital implications for the next generation of influenza virus and SARS-CoV-2 vaccines. IMPORTANCE Obesity is associated with increased morbidity and mortality from influenza and SARS-CoV-2 infection. While vaccination is the most effective strategy for preventing influenza virus infection, our previous studies showed that influenza vaccines fail to provide optimal protection in obese individuals despite reaching canonical correlates of protection. Here, we show that obesity may impair immune history in humans and cannot be overcome by seasonal vaccination, especially in younger individuals with decreased lifetime exposure to infections and seasonal vaccines. Low baseline immune history is associated with decreased protective antibody responses. Obesity potentially handicaps overall responses to vaccination, biasing it toward responses to linear epitopes, which may reduce protective capacity. Taken together, our data suggest that young obese individuals are at an increased risk of reduced protection by vaccination, likely due to altered immune history biased toward nonprotective antibody responses. Given the worldwide obesity epidemic coupled with seasonal respiratory virus infections and the inevitable next pandemic, it is imperative that we understand and improve vaccine efficacy in this high-risk population. The design, development, and usage of vaccines for and in obese individuals may need critical evaluation, and immune history should be considered an alternate correlate of protection in future vaccine clinical trials.
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Affiliation(s)
- Marwa Abd Alhadi
- Department of Microbiology, Immunology and Genetics, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel
- National Institute for Biotechnology in the Negev, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Lilach M. Friedman
- Department of Microbiology, Immunology and Genetics, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel
- National Institute for Biotechnology in the Negev, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Erik A. Karlsson
- Virology Unit, Institute Pasteur du Cambodge, Phnom Penh, Cambodia
- Department of Infectious Diseases, St. Jude Children’s Research Hospital, Memphis, Tennessee, USA
| | - Liel Cohen-Lavi
- National Institute for Biotechnology in the Negev, Ben-Gurion University of the Negev, Beer-Sheva, Israel
- Department of Industrial Engineering and Management, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Anat Burkovitz
- Department of Microbiology, Immunology and Genetics, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel
- National Institute for Biotechnology in the Negev, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Stacey Schultz-Cherry
- Department of Infectious Diseases, St. Jude Children’s Research Hospital, Memphis, Tennessee, USA
| | - Terry L. Noah
- Department of Pediatrics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Samuel S. Weir
- Department of Family Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Lester M. Shulman
- Department of Epidemiology and Preventive Medicine, School of Public Health, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Melinda A. Beck
- Department of Nutrition, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina, USA
| | - Tomer Hertz
- Department of Microbiology, Immunology and Genetics, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel
- National Institute for Biotechnology in the Negev, Ben-Gurion University of the Negev, Beer-Sheva, Israel
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
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Abd Alhadi M, Friedman L, Karlsson E, Cohen-Lavi L, Burkovitz A, Schultz-Cherry S, Noah TL, Weir SS, Shulman L, Beck MA, Hertz T. Obesity is Associated with Impaired Immune History to Influenza. SSRN Journal 2022. [DOI: 10.2139/ssrn.4292855] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/02/2023]
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Abd Alhadi M, Friedman LM, Karlsson EA, Cohen-Lavi L, Burkovitz A, Schultz-Cherry S, Noah TL, Weir SS, Shulman LM, Beck MA, Hertz T. Obesity is associated with an altered baseline and post-vaccination influenza antibody repertoire. medRxiv 2021:2021.03.02.21252785. [PMID: 33688682 PMCID: PMC7941659 DOI: 10.1101/2021.03.02.21252785] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
As highlighted by the ongoing COVID-19 pandemic, vaccination is critical for infectious disease prevention and control. Obesity is associated with increased morbidity and mortality from respiratory virus infections. While obese individuals respond to influenza vaccination, what is considered a seroprotective response may not fully protect the global obese population. In a cohort vaccinated with the 2010-2011 trivalent inactivated influenza vaccine, baseline immune history and vaccination responses were found to significantly differ in obese individuals compared to healthy controls, especially towards the 2009 pandemic strain of A/H1N1 influenza virus. Young, obese individuals displayed responses skewed towards linear peptides versus conformational antigens, suggesting aberrant obese immune response. Overall, these data have vital implications for the next generation of influenza vaccines, and towards the current SARS-CoV-2 vaccination campaign.
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Affiliation(s)
- Marwa Abd Alhadi
- Department of Microbiology, Immunology and Genetics, Faculty of Health Sciences, Ben-Gurion University of the Negev; Beer-Sheva, Israel
- National Center for Biotechnology in the Negev, Ben-Gurion University of the Negev; Beer-Sheva, Israel
| | - Lilach M. Friedman
- Department of Microbiology, Immunology and Genetics, Faculty of Health Sciences, Ben-Gurion University of the Negev; Beer-Sheva, Israel
- National Center for Biotechnology in the Negev, Ben-Gurion University of the Negev; Beer-Sheva, Israel
| | - Erik A Karlsson
- Virology Unit, Institute Pasteur du Cambodge; Phnom Penh, Cambodia
- Department of Infectious Diseases, St. Jude Children’s Research Hospital; Memphis, TN, USA
| | - Liel Cohen-Lavi
- National Center for Biotechnology in the Negev, Ben-Gurion University of the Negev; Beer-Sheva, Israel
- Department of Industrial Engineering and Management, Ben-Gurion University of the Negev; Beer-Sheva, Israel
| | - Anat Burkovitz
- Department of Microbiology, Immunology and Genetics, Faculty of Health Sciences, Ben-Gurion University of the Negev; Beer-Sheva, Israel
- National Center for Biotechnology in the Negev, Ben-Gurion University of the Negev; Beer-Sheva, Israel
| | - Stacey Schultz-Cherry
- Department of Infectious Diseases, St. Jude Children’s Research Hospital; Memphis, TN, USA
| | - Terry L Noah
- Department of Pediatrics, University of North Carolina at Chapel Hill; NC, USA
| | - Samuel S Weir
- Department of Family Medicine, University of North Carolina at Chapel Hill; NC, USA
| | - Lester M. Shulman
- Dept. of Epidemiology and Preventive Medicine, School of Public Health, Sackler Faculty of Medicine, Tel Aviv University; Tel Aviv, Israel
| | - Melinda A Beck
- Department of Nutrition, Gillings School of Global Public Health, UNC, Chapel Hill; NC, USA
| | - Tomer Hertz
- Department of Microbiology, Immunology and Genetics, Faculty of Health Sciences, Ben-Gurion University of the Negev; Beer-Sheva, Israel
- National Center for Biotechnology in the Negev, Ben-Gurion University of the Negev; Beer-Sheva, Israel
- Vaccine and Infectious Disease Division, Fred Hutch Cancer Research Center; Seattle, WA, USA
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Weir SS, Page C, Newton WP. Continuity and Access in an Academic Family Medicine Center. Fam Med 2016; 48:100-107. [PMID: 26950780] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
BACKGROUND AND OBJECTIVES A personal physician and enhanced access to care are principles of the patient-centered medical home. Despite the importance of these concepts, measuring and improving interpersonal continuity of care and access to care in academic family medicine centers has received little attention. The authors describe their program's methods and results to maximize continuity of care and minimize delays for care using proven principles from improvement science. METHODS In 2004, a diverse quality improvement team from our family medicine center joined a breakthrough collaborative with other primary care practices focused on improving appointment access and continuity of care. We followed the model for improvement with a specific aim, explicit measures, and ambitious goals. The team adapted and applied principles from a change package presented in the collaborative to improve access and continuity. We planned and performed small tests of change that were subsequently optimized and spread to the entire practice. RESULTS Average time to third available appointment for a routine physical improved from 22 days to 8 days. Average usual provider continuity (UPC) across all primary care physicians in the practice improved from 54% to 68%. Among resident physicians, UPC improved from 55% to 68%. These results have been sustained over 5 years. CONCLUSIONS Despite multiple challenges in academic teaching practices, the continuous use of improvement methods to apply proven change concepts minimizes delay for care and maximizes continuity of care. The residency continuity practice can and should be a cornerstone of residency curriculum.
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Affiliation(s)
- Samuel S Weir
- Department of Family Medicine, University of North Carolina
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Paich HA, Sheridan PA, Handy J, Karlsson EA, Schultz-Cherry S, Hudgens MG, Noah TL, Weir SS, Beck MA. Overweight and obese adult humans have a defective cellular immune response to pandemic H1N1 influenza A virus. Obesity (Silver Spring) 2013; 21:2377-86. [PMID: 23512822 PMCID: PMC3695020 DOI: 10.1002/oby.20383] [Citation(s) in RCA: 129] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/12/2012] [Accepted: 12/28/2012] [Indexed: 12/12/2022]
Abstract
OBJECTIVE Obese adults have a greater risk of morbidity and mortality from infection with pandemic H1N1 influenza A virus (pH1N1). The objective of the present study was to elucidate the specific mechanisms by which obesity and overweight impact the cellular immune response to pH1N1. DESIGN AND METHODS Peripheral blood mononuclear cells from healthy weight, overweight, and obese individuals were stimulated ex vivo with live pH1N1 and then markers of activation and function were measured using flow cytometry and cytokine secretion was measured using cytometric bead array assays. RESULTS CD4(+) and CD8(+) T cells from overweight and obese individuals expressed lower levels of CD69, CD28, CD40 ligand, and interleukin-12 receptor, as well as, produced lower levels of interferon-γ and granzyme B, compared with healthy weight individuals, suggesting deficiencies in activation and function are indicated. Dendritic cells from the three groups expressed similar levels of major histocompatibility complex-II, CD40, CD80, and CD86, as well as, produced similar levels of interleukin-12. CONCLUSIONS The defects in CD4(+) and CD8(+) T cells may contribute to the increased morbidity and mortality from pH1N1 in obese individuals. These data also provide evidence that both overweight and obesity cause impairments in immune function.
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Affiliation(s)
- Heather A. Paich
- Department of Nutrition, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599
| | - Patricia A. Sheridan
- Department of Nutrition, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599
| | - Jean Handy
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599
| | - Erik A Karlsson
- Department of Infectious Diseases, St. Jude Children’s Research Hospital, Memphis, TN, 38105
| | - Stacey Schultz-Cherry
- Department of Infectious Diseases, St. Jude Children’s Research Hospital, Memphis, TN, 38105
| | - Michael G. Hudgens
- Department of Biostatistics, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599
| | - Terry L. Noah
- Department of Pediatrics, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599
| | - Samuel S. Weir
- Department of Family Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599
| | - Melinda A. Beck
- Department of Nutrition, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599
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Paich HA, Sheridan PA, Noah TL, Weir SS, Beck MA. The Influence of Type II Diabetes on the Immune Response of Obese Adults. FASEB J 2013. [DOI: 10.1096/fasebj.27.1_supplement.643.13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
| | | | - Terry L. Noah
- University of North Carolina at Chapel HillChapel HillNC
| | - Samuel S. Weir
- University of North Carolina at Chapel HillChapel HillNC
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Weir SS. Disease management in primary care: rapid cycle quality improvement of asthma care. N C Med J 2005; 66:221-2. [PMID: 16130948] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Affiliation(s)
- Samuel S Weir
- Department of Family Medicine, University of North Carolina School of Medicine, USA.
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Cleland J, Boerma JT, Carael M, Weir SS. Monitoring sexual behaviour in general populations: a synthesis of lessons of the past decade. Sex Transm Infect 2005; 80 Suppl 2:ii1-7. [PMID: 15572634 PMCID: PMC1765850 DOI: 10.1136/sti.2004.013151] [Citation(s) in RCA: 92] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
This supplement contains selected papers from a workshop on the measurement of sexual behaviour in the era of HIV/AIDS held at the London School of Hygiene and Tropical Medicine in September 2003. The focus was on low and middle income countries, where the majority of HIV infections occur. The motive for holding such a meeting is easy to discern. As the AIDS pandemic continues to spread and as prevention programmes are scaling up, the need to monitor trends in sexual risk behaviours becomes ever more pressing. Behavioural data are an essential complement to biological evidence of changes in HIV prevalence or incidence. Biological evidence, though indispensable, is by itself insufficient for policy and programme guidance. AIDS control programmes need to be based on monitoring of not only trends in infections but also of trends in those behaviours that underlie epidemic curtailment or further spread.
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Affiliation(s)
- J Cleland
- Centre for Population Studies, London School of Hygiene & Tropical Medicine, London, UK.
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Abstract
OBJECTIVES To assess the role in an overall monitoring strategy of the PLACE method of estimating local trends in sexual behaviour among individuals at social venues in areas at increased risk of HIV transmission. METHODS Public venues identified by community informants as places where people meet new sexual partners were visited and characterised in Karaganda, Kazakhstan, in 2002 and 2003, and in a township in South Africa in 2000 and 2003. At a subset of venues, a representative sample of individuals socialising at the venue were interviewed about their sexual behaviour. The age distribution and partnerships rates of those socialising at these venues were compared by year and with national data from Kazakhstan and South Africa obtained via household surveys. RESULTS Women and men socialising at venues were younger and had higher rates of new and concurrent partnerships than men and women interviewed in national household surveys. There was little apparent change in sexual behaviour between 2002 and 2003 in Karaganda. In the South African township, there was a reduction in sexual partnerships and an increase in condom use, possibly due to a local AIDS prevention programme. CONCLUSION Findings from the PLACE method supplement national data on sexual behaviours with data from key populations in high transmission areas, inform local targeting of interventions, and, when subsequent rounds of PLACE are implemented, can evaluate change in target populations.
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Affiliation(s)
- S S Weir
- University of North Carolina, Chapel Hill, NC 27516-3997, USA.
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Weir SS, Morroni C, Coetzee N, Spencer J, Boerma JT. A pilot study of a rapid assessment method to identify places for AIDS prevention in Cape Town, South Africa. Sex Transm Infect 2002; 78 Suppl 1:i106-13. [PMID: 12083428 PMCID: PMC1765815 DOI: 10.1136/sti.78.suppl_1.i106] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
A multidisciplinary approach appears promising for focusing interventions. The PLACE method (priorities for local AIDS control efforts) identifies where prevention programmes can access sexual networks containing individuals with high rates of new partner acquisition and provides information about whether sexually transmitted disease (STD) or AIDS prevention programmes are in place at those sites. The method provides useful information at relatively low cost, regardless of the phase of the HIV or STD epidemic. For example, in the growth phase of an epidemic, information on where people with high rates of new partner acquisition meet new sexual partners could be used to inform targeted surveillance or screening programmes to catch early cases.
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Affiliation(s)
- S S Weir
- Carolina Population Center, University of North Carolina, Chapel Hill 27516-3997, USA
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Weir SS, Roddy RE, Zekeng L, Ryan KA. Association between condom use and HIV infection: a randomised study of self reported condom use measures. J Epidemiol Community Health 1999; 53:417-22. [PMID: 10492735 PMCID: PMC1756929 DOI: 10.1136/jech.53.7.417] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
STUDY OBJECTIVE To compare the association between different measures of condom use and prevalent HIV infection. DESIGN Randomised cross sectional study to assess association between HIV infection and different measures of self reported condom use. Female sex workers were randomised to one of five different face to face questionnaires on condom use. Three questionnaires used always to never scales to measure use but differed in the reference period for use; a fourth asked about use in the last 10 coital acts; and the fifth was a retrospective log of coital acts in the past two weeks. Use was assessed with new clients, repeat clients, and non-clients. SETTING Yaoundé and Douala, Cameroon. PARTICIPANTS 2266 female sex workers. MAIN RESULTS The association between condom use and prevalent HIV infection varied for different measures of condom use. None of the five level measures showed a dose response protective effect of condom use. Measures aimed at reducing recall bias (measures based on the past 10 coital acts or a coital log) showed little or no association with prevalent infection. Measures based on the past month or six months had a stronger association with prevalent infection. Regardless of the type of measure or reference period, the strongest association between use and infection was for use with partners who were not clients. CONCLUSION These findings underscore challenges described by others of measuring condom use and interpreting the association between use and prevalent infection.
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Affiliation(s)
- S S Weir
- Family Health International, Durham, NC 27709, USA
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Feldblum PJ, Weir SS, Cates W. The protective effect of condoms and nonoxynol-9 against HIV infection: a response to Wittkowski and colleagues. Am J Public Health 1999; 89:108-10. [PMID: 9987480 PMCID: PMC1508499 DOI: 10.2105/ajph.89.1.108-a] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Abstract
BACKGROUND Nonoxynol 9 is a proved spermicide, but whether it is also a microbicide is uncertain. A truly effective vaginal microbicide would reduce the susceptibility of women to sexually transmitted diseases, including infection with the human immunodeficiency virus (HIV). METHODS We enrolled 1292 HIV-negative female sex workers in Cameroon and enrolled them in a double-blind, placebo-controlled study in which the participants were randomly assigned to use either a film containing 70 mg of nonoxynol 9 or a placebo film, inserted into the vagina before intercourse. All of the women were provided with latex condoms and were instructed to have their male sexual partners use them. At monthly follow-up visits, we examined the women with a colposcope for genital lesions, tested endocervical specimens for gonorrhea and chlamydia infection with DNA probes, tested for HIV infection, and treated the women for curable sexually transmitted diseases. RESULTS The rates of HIV infection (cases per 100 woman-years) were 6.7 in the nonoxynol 9 group and 6.6 in the placebo group (rate ratio, 1.0; 95 percent confidence interval, 0.7 to 1.5). The rates of genital lesions were 42.2 cases per 100 woman-years in the nonoxynol 9 group and 33.5 in the placebo group (rate ratio, 1.3; 95 percent confidence interval, 1.0 to 1.6). The rates of gonorrhea were 33.3 and 31.1 cases per 100 woman-years in the nonoxynol 9 and placebo groups, respectively (rate ratio, 1.1; 95 percent confidence interval, 0.8 to 1.4). The corresponding rates of chlamydia infection in the nonoxynol 9 group and the placebo group were 20.6 and 22.2 per 100 woman-years (rate ratio, 0.9; 95 percent confidence interval, 0.7 to 1.3). The women reported that condoms were used during 90 percent of sexual acts. CONCLUSIONS The use of a nonoxynol 9 vaginal film did not reduce the rate of new HIV, gonorrhea, or chlamydia infection in this group of sex workers who used condoms and received treatment for sexually transmitted diseases.
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Affiliation(s)
- R E Roddy
- Epidemiology Unit, Family Health International, Durham, NC 27709, USA
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Weir SS, Roddy RE, Zekeng L, Ryan KA, Wong EL. Measuring condom use: asking "do you or don't you" isn't enough. AIDS Educ Prev 1998; 10:293-302. [PMID: 9721382] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
This article compares cross-sectional measures of condom use among 2,269 female sex workers in Cameroon randomly assigned to receive one of five different questionnaires measuring condom use. We found that the level of reported condom use varied depending on the type of survey questions used. Measures based on 2-week coital logs or the past 10 acts categorized more women as "100%" or "0%" users than always-to-never scales categorized women as "always" or "never" users. Consistency of use also varied by type of partner. Internal consistency of responses was high. Future studies should assess differences in prospective measures of condom use and the level of association between various measures and infection with sexually transmitted disease.
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Affiliation(s)
- S S Weir
- Family Health International, Durham, NC, USA
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Abstract
The aim of the study was to determine the prevalence of sexually transmitted diseases (STDs), describe the frequency of genitourinary symptoms and signs, and to assess the accuracy of clinical diagnoses of STD in a cohort of Cameroonian sex workers. Physical examinations were conducted on 1233 sex workers in Yaoundé and Douala, Cameroon. Symptoms experienced within the 14 days prior to examination were collected. Women were tested for gonorrhoea, chlamydia infection, and trichomoniasis. Doctors' clinical impressions were compared with laboratory tests. Prevalence of cervical infection and trichomoniasis was 20%. A high percentage of abnormal signs and symptoms was found in this cohort. Clinical diagnosis for cervicitis and trichomoniasis had low sensitivities (<50%) while specificity remained high (>65%). In conclusion STDs are common among sex workers in Cameroon. Clinical diagnosis was not an accurate predictor of infection at the individual level in this population at risk of STD.
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Affiliation(s)
- K A Ryan
- Family Health International, Durham, NC, USA.
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Ryan KA, Roddy RE, Zekeng L, Weir SS, Tamoufé U. Characteristics associated with prevalent HIV infection among a cohort of sex workers in Cameroon. Sex Transm Infect 1998; 74:131-5. [PMID: 9634326 PMCID: PMC1758100 DOI: 10.1136/sti.74.2.131] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
OBJECTIVE To determine prevalence of HIV infection in a cohort of female sex workers in Cameroon, and to describe characteristics associated with HIV infection in this population. METHODS In a cross sectional study, 2260 female sex workers in Cameroon were interviewed and screened for HIV serostatus. A standardised questionnaire was used to collect information on sociodemographic characteristics and sexual and health behaviours. RESULTS Seropositive participants (18%) were more likely to be over age 25, have four or more children, live in Yaoundé or Douala for 5 years or less, solicit clients in their homes or on the street, have a low educational level, earn a weekly income of less than $24, and have no other occupation outside of sex work. A logistic regression model of selected sociodemographic characteristics indicated that women at particularly high odds of HIV infection were older, poorer, and new immigrants to their city of residence. CONCLUSION This seroprevalence study found a lower HIV prevalence than had been previously reported. Although our results are different, this group is still at much higher risk of HIV infection than the population as a whole.
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Affiliation(s)
- K A Ryan
- Family Health International, Durham, NC. USA
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Abstract
The purpose of this paper is to assess the internal consistency of self-reported condom use among sex workers in Puerto Plata and Santo Domingo, Dominican Republic. We examined the responses to questions about condom use among 4 cross-sectional samples of sex workers. We compared measures based on: (1) questions using always-to-never scales; (2) questions about use with the past 5 clients; and (3) questions about use in the past week obtained from a retrospective coital log. In each sample, more women reported 'always' using condoms with clients than with each of the past 5 clients. In 3 of the 4 samples, only about half of the women who reported 'always' using condoms used condoms with the most recent 5 clients and with all clients in the past week. Internal consistency was significantly higher when the comparison was limited to use with the most recent 5 clients and use in the past week. Self-reported measures of condom use can be difficult to interpret. Assessing the internal consistency of several measures of use provides insight into the strengths and weaknesses of each measure.
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Affiliation(s)
- S S Weir
- Family Health International, Durham, NC, USA
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Lamptey PR, Kamenga MC, Weir SS. Prevention of sexual transmission of HIV in sub-Saharan Africa: lessons learned. AIDS 1998; 11 Suppl B:S63-77. [PMID: 9416368] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- P R Lamptey
- Family Health International, Arlington, VA 22201, USA
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Hira SK, Feldblum PJ, Kamanga J, Mukelabai G, Weir SS, Thomas JC. Condom and nonoxynol-9 use and the incidence of HIV infection in serodiscordant couples in Zambia. Int J STD AIDS 1997; 8:243-50. [PMID: 9147157 DOI: 10.1258/0956462971919994] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
We aimed to measure the effectiveness of latex condoms and of nonoxynol-9 [N-9] spermicides, in preventing HIV transmission in heterosexual serodiscordant couples in Lusaka. Each couple was examined at clinic visits scheduled at 3-month intervals for one year or more per couple, or until seroconversion or discontinuation. Couples were given condoms and their choice of 3 N-9 products and advised to use both at every intercourse. Sexual exposure was ascertained from coital logs that recorded coitus and barrier method use. HIV serological testing was done at each clinic visit (ELISA and Western blot if positive). One hundred and ten discordant couples were followed for a mean of 17.6 months. Seventy-eight per cent of coital episodes were protected by condoms, 85% by spermicides and 6.4% were unprotected. Fourteen seroconversions occurred (8.7 infections per 100 couple-years [c-y]). The rate was higher among seronegative men than seronegative women. Among couples who reported using condoms at every intercourse the infection rate was 2.3/100 c-y, compared with 10.7/100 c-y among couples using condoms less consistently (rate ratio [RR] 0.2; 95% confidence interval [CI] 0-1.6). Among couples who reported using N-9 at every intercourse, the seroconversion rate was 6.9/100 c-y; among couples who reported less than full-time N-9 use, the rate was 8.9/100 c-y (RR 0.8; 95% CI 0.2-2.8). Among the subset of female seronegatives, the N-9 RR was 0.5 (95% CI 0.1-3.8). But when we calculated HIV rates according to N-9 consistency in coital acts when condoms were not used, there was no evidence of protection with higher N-9 use. Consistent use of latex condoms reduces the incidence of HIV infection, but the association between N-9 spermicides and HIV is less clear. The current study could not provide compelling data on the impact of N-9 spermicide use on risk of HIV infection. The study's small size, as well as the consistency of concurrent condom use, limited our inferences. Available spermicide products must be studied further.
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Affiliation(s)
- S K Hira
- University Teaching Hospital, Lusaka, Zambia
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Kalichman SC, Adair V, Somlai AM, Weir SS. The perceived social context of AIDS: study of inner-city sexually transmitted disease clinic patients. AIDS Educ Prev 1995; 7:298-307. [PMID: 7577306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
The present study investigated perceptions of AIDS as a social problem relative to 10 other problems in a sample of 194 inner-city sexually transmitted disease (STD) clinic patients. Within-subjects analyses showed that AIDS was viewed as a more serious problem than housing, alcoholism, and child care, while AIDS was less of a problem than employment, drug abuse, crime, discrimination, and teen pregnancy, and no different from transportation and health care. Factor analysis was used to identify the interrelationships among social problems as perceived by STD patients. For men, factor analysis showed that AIDS was most closely related to crime, drug abuse, teen pregnancy, and discrimination, with these problems constituting the first factor and accounting for most of the variance in the analysis. Men also placed AIDS with alcoholism and child care on the third factor accounting for little variance. For women, however, AIDS clustered most closely with alcoholism and child care, accounting for a minimal amount of variance in the analysis. Results further showed that perceptions of social problems among women correlated with HIV-risk-related behaviors. The structural context of social problems, within which AIDS is embedded, is discussed with reference to HIV-AIDS-prevention interventions.
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Affiliation(s)
- S C Kalichman
- Center for AIDS Intervention Research, Medical College of Wisconsin, USA
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Nabulsi AA, Folsom AR, Heiss G, Weir SS, Chambless LE, Watson RL, Eckfeldt JH. Fasting hyperinsulinemia and cardiovascular disease risk factors in nondiabetic adults: stronger associations in lean versus obese subjects. Atherosclerosis Risk in Communities Study Investigators. Metabolism 1995; 44:914-22. [PMID: 7616851 DOI: 10.1016/0026-0495(95)90245-7] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The association between hyperinsulinemia and atherogenic risk factors has not been well studied in blacks and may be different for obese versus lean individuals. To investigate this possibility and to confirm the associations of hyperinsulinemia with cardiovascular disease risk factors in blacks and whites, we analyzed the joint associations of fasting serum insulin and obesity with risk factors in the Atherosclerosis Risk in Communities (ARIC) Study (1,293 black men, 4,797 white men, 2,033 black women, and 5,445 white women). Insulin values > or = 90th percentile (> or = 21 microU/mL) constituted hyperinsulinemia; body mass index (BMI) values > or = 27.3 kg/m2 for women and > or = 27.8 for men constituted obesity. Participants with hyperinsulinemia in all four race-sex groups had more atherogenic levels of most risk factors studied than those with normoinsulinemia. Among black men and women, mean levels of triglycerides, low-density lipoprotein cholesterol (LDL-C), apolipoprotein (apo) B, glucose, and fibrinogen (men only) were higher in hyperinsulinemic lean participants as compared with the normoinsulinemic obese group. Furthermore, most associations between insulin level and risk factors were stronger among lean versus obese subjects. For example, among lean black men, the difference in mean triglyceride concentration between those with hyperinsulinemia and those with normoinsulinemia was 147 - 99 = 48 mg/dL; among obese black men, the difference was 155 - 121 = 34 mg/dL (P < .05 for the interaction). Generally, similar negative interactions between BMI and insulin concentration were also observed among whites.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- A A Nabulsi
- Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis 55454-1015, USA
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Abstract
OBJECTIVES To measure the associations between use of nonoxynol-9 (N-9) and incidence of genital ulcers, and incident ulcers and HIV seroconversion. METHODS In a study of barrier contraceptive use and HIV infection, 273 female sex workers used condoms and 100 mg N-9 suppositories, and recorded sexual activity on coital logs. Genital ulcers were diagnosed clinically at monthly clinic visits. HIV infection was diagnosed by ELISA and Western blot. We calculated ulcer incidence rates by level of N-9 use. A nested matched case-control analysis assessed the effect of ulcers on HIV acquisition. RESULTS More frequent N-9 use was not associated with genital ulcers and may have been protective against the lesions. Ulceration was not a strong risk factor for HIV acquisition in this study (odds ratio 1.1; 95% confidence interval 0.3-3.5). CONCLUSIONS Frequent use of N-9 can cause genital irritation and ulceration. Ulcers, in turn, may be risk factors for HIV acquisition. This study, however, did not find an association between N-9 use and ulcers, nor between ulcers and HIV. There is probably a threshold of N-9 use frequency or dose below which the risk of ulceration is minimal. Ulcers due to infectious causes may have been prevented by N-9 use in this cohort.
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Affiliation(s)
- S S Weir
- Family Health International, Research Triangle Park, North Carolina 27709, USA
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Abstract
OBJECTIVE The role of gonorrhea in facilitating acquisition of HIV infection has only recently been studied. A previous nested case-control analysis in a cohort of female sex workers in Zaïre found a strong association between HIV seroconversion and prior gonorrheal infection. The objective of this study was to replicate the Zaïre study analysis in a cohort of 273 Cameroonian sex workers to determine whether gonorrhea increased the risk of HIV acquisition, and if the crude association between gonorrheal infection and HIV acquisition was weakened when the level of unprotected coitus was more carefully controlled. METHODS We conducted a nested case-control study of initially HIV-1-negative women (n = 273) followed prospectively (with monthly sexually transmitted disease check-ups and 3-monthly HIV-1 serology). As in Zaïre, cases (seroconverters, n = 17) were compared with controls (women who remained HIV-1-negative, n = 68) for incidence of gonorrhea and sexual exposure during the presumed period of HIV-1 acquisition. RESULTS The association between gonorrheal infection and subsequent HIV acquisition was stronger in Zaïre than in Cameroon [crude odds ratios (OR), 6.3 versus 2.2]. In both the Zaïre and Cameroon data the crude OR were reduced (6.3 to 4.8, and 2.2 to 1.7, respectively) by controlling for risk factors including a dichotomous variable indicating irregular or no condom use. When this variable was replaced in the Cameroon data with a more precise continuous variable indicating the percentage of unprotected coital acts, the gonorrhea OR was further reduced to 1.4 (95% confidence interval, 0.4-4.9). CONCLUSION These results suggest that in the Cameroon cohort, gonorrheal infection did not facilitate HIV acquisition, but that having gonorrhea was a marker for unprotected coitus that facilitated HIV acquisition. The data demonstrate how OR can be overestimated when imprecise dichotomous measures of unprotected coitus are used. Future studies should plan for better control of self-reported condom use.
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Affiliation(s)
- S S Weir
- Family Health International, Research Triangle Park, NC 27709
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Abstract
OBJECTIVES Although condoms are the best defense against sexually transmitted disease, little is known about the effectiveness of female-controlled methods containing nonoxynol-9 as backup protection when condoms are not being used. METHODS To assess the extent to which nonoxynol-9 protects women against gonorrhea, a cohort of 303 female sex workers (prostitutes) in Yaounde, Cameroon, were asked to use condoms and suppositories containing nonoxynol-9 at every sexual encounter and to record daily sexual activity and use of condoms and suppositories on coital logs that were reviewed monthly. Evidence of gonorrheal infection was based on a positive gonorrhea culture. Stratified analysis and proportional hazards regression were used to estimate rate ratios. RESULTS Forty-one women enrolled in the study were excluded from the current analysis. The estimated incidence of gonorrhea was 6.2 infections per 100 person-months of observation. Incidence rate ratios estimated from proportional hazards regression models controlling for condom use showed that using nonoxynol-9 during acts not protected by condoms reduced the risk of infection. CONCLUSIONS Although the protective effect of condoms against sexually transmitted disease is greater than that afforded by nonoxynol-9, using nonoxynol-9 when condoms are not used is a far better strategy in gonorrhea prevention than using no method at all.
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Affiliation(s)
- S S Weir
- Family Health International, Research Triangle Park, NC 27709
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Abstract
OBJECTIVE Expert testimony in malpractice cases is often subjective and biased. Decision-analytic techniques might provide an objective basis for such testimony. DESIGN Case report. This article reports the case of a patient with chest pain that resulted in a malpractice suit alleging a delay in diagnosis of coronary artery disease. SETTING The case occurred in a private practice; the expert witnesses and the decision analysis originated from a university teaching hospital. METHODS A decision tree and threshold analysis were used to define the thresholds of disease probability at which either testing or treatment should be implemented. The expert testimony of two witnesses that exercise stress testing was the standard of care was compared with the results of the decision analysis. MAIN RESULTS Decision analysis supported the view that cardiac catheterization would have been the more appropriate test. CONCLUSIONS Techniques of decision analysis provide a structured and quantitative basis for empirical judgment and may help to minimize current problems with expert testimony.
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Affiliation(s)
- S S Weir
- Department of Family Medicine, University of North Carolina, Chapel Hill 27599
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