Title: Analysis of the immunologic status of a newly diagnosed HIV positive population in China

Transcription

1 Author's response to reviews Title: Analysis of the immunologic status of a newly diagnosed HIV positive population in China Authors: Yinzhong Shen (027465@163.com) Hongzhou Lu (luhongzhou@fudan.edu.cn) Zhenyan Wang (a1s2r@163.com) Tangkai Qi (qitangkai@shaphc.org) Jiangrong Wang (wangjiangrong@shaphc.org) Version: 2 Date: 2 May 2013 Author's response to reviews: see over

2 May 2, 2013 Department of Infectious Diseases Shanghai Public Health Clinical Center Fudan University 2901 Caolang Road, Jinshan Shanghai PR China Tel/Fax: Dear Sir or Madam: Thank you for giving me the opportunity to revise and resubmit my manuscript. According to the reviewers comments, I have revised the manuscript for review. I have provided a cover letter giving a point-by-point response to the reviewers concerns. I highlight the changes to my manuscript within the document by using coloured text. Thank you again for your good suggestions and for the opportunity to consider my manuscript.. This revised manuscript has not been submitted for publication to any other journal. My co-authors and I hope you will find our manuscript worthy of consideration for publication in BMC Infectious Diseases. Thanking you in anticipation of acknowledgment of receipt of our manuscript. Sincerely, Yinzhong Shen Hongzhou Lu =========================================================================== The following is a letter with a point-by-point response to the reviewers comments and a point-by-point description of the changes made. =========================================================================== 1

3 Reviewer's report: Major Compulsory Revisions Please state the source of the subjects. Were they patients coming for HIV/AIDS treatment or subject under certain screening program from a survey? If the study sample had a mixed source, please breakdown the sources by province. Reply: In the revised manuscript, we have stated the source of the subjects in the Study population section. The subjects were newly diagnosed HIV/AIDS patients who had not received ART and were addressed to the HIV diagnosis and management hospitals, since they have symptoms and or risky behaviors. We have re-written the part as follows: This study was part of the research contents of the 12th Five-Year infectious disease research program which was supported by the Ministry of Science and Technolgy, China. We conducted a cross-sectional survey on HIV/AIDS in China s HIV epidemic provinces and municipalities including in Shaanxi, Xinjiang, Hunan, Guangdong, Yunnan, Heilongjiang, Shanghai, Henan, Jiangxi, and Guangxi during 2009 to The survey subjects were newly diagnosed HIV/AIDS patients who had not received ART. The patients were addressed to the HIV diagnosis and management hospitals, since they have symptoms and or risky behaviors. Patients aged 18 years or more at the time of enrolment with documented HIV-1 infection were eligible for this study. Only antiretroviral naïve patients were included in the study. Being on ART was an exclusion criterion. Antiretroviral experienced but currently untreated patients were not eligible for this study. All patients were confirmed to be positive for HIV antibody through laboratory detection, and the diagnosis was in line with national HIV/AIDS 2

4 diagnostic criteria. Demographic characteristics and medical histories of the patients were recorded. Please describe the counseling process before and after the blood test was done. Reply: The HIV/AIDS patients were addressed to the HIV diagnosis and management hospitals, since they have symptoms and or risky behaviors. The doctors would provide comprehensive care for the HIV/AIDS people according to the China guidelines for HIV-positive patients. In the revised manuscript, we have added this information into the Blood samples section. In addition, we have added a new section Data Collection in the revised manuscript to show the counseling process. We have re-written the part as follows: Blood samples For newly diagnosed HIVAIDS patients, two-milliliter venous blood samples were obtained from each individual at the initial visit in order to make a CD4 count. Written informed consent was obtained for all subjects; consent forms and procedures, as well as survey protocol, were approved by the Shanghai Public Health Clinical Center Ethics Committee. CD4 count was measured by flow cytometry at the clinical laboratories in each province. All the study laboratories successfully completed a standardization and certification program. The study doctors provided comprehensive care for the study patients according to the guidelines for diagnosis and treatment of HIV/AIDS in China before and after the blood test was done. Data Collection Data were collected according to standardised criteria. On enrolment, standardised data collection forms were completed at the sites providing information from patient interview and 3

5 patient case notes. Data collected on newly identified cases included demographic information, risk-behavior information (injection drug use, history of heterosexual or homosexual sex, receipt of blood transfusion), and laboratory test results. Variables of interest included province, age, sex, ethnicity, and HIV transmission route. Age was denoted as 24, 25-34, 35-44, or 55 years. Race/ethnicity was designated as Han, Zhuang, Uygur or other. HIV transmission route was categorized as sexual contact (including homosexual or heterosexual), blood transfusion, injection drug use, or unknown transmission risk. Who paid for the test? Was it free? If not how much were the patients charged for the HIV test and the CD+ count? Reply: In the revised manuscript, we added this information. In the Study population section., we stated: This study was part of the research contents of the 12th Five-Year infectious disease research project which was supported by the Ministry of Science and Technolgy, China. In the Acknowledgments section of the original manuscript, we had pointed out the funding of this research: This work was supported by Key Research grants from the Ministry of Science and Technolgy, the People s Republic of China (NO: 2012ZX ). So the tests were paid by the research funding. CD4 test costs about 280 RMB (about US dollars). In China, the government provides free HIV antibody test for VCT individuals. 4

6 What was the response rate by province. How many patients (percent) had HIV positive test but CD+ count not done?. Reply: In the Results Patient characteristics section, we had provided the information: We investigated a total of 2866 newly diagnosed HIV-infected patients; 1048 patients were from Guangxi, 529 from Yunnan, 51 from Henan, 222 from Xinjiang, 64 from Jiangxi, 197 from Guangdong, 95 from Shaanxi, 176 from Hunan, 80 from Heilongjiang, and 404 from Shanghai. We conducted this survey in 10 provinces including 11 hospitals, all the hospitals are the speciallist hospital for infectious diseases (including AIDS). All patients (100%) enrolled in our research had CD4 test. How was the sample size calculated? Reply: We conducted a cross-sectional survey on HIV/AIDS in China s HIV epidemic provinces and municipalities including in Shaanxi, Xinjiang, Hunan, Guangdong, Yunnan, Heilongjiang, Shanghai, Henan, Jiangxi, and Guangxi during 2009 to Our study was cross-sectional, we did not calculate the sample at first, we just wanted to enroll more subjects and we conducted our study in 10 provinces. At last, we enrolled a total of 2866 newly diagnosed HIV-infected patients. This is a large survey of immunologic status in newly diagnonsed HIV/AIDS patients in China. 5

7 The result section should be extensively revised As epidemiology of HIV/AIDs may vary by province, which is the highlight of this paper, Table 1 should have characteristics (in row) broken down by province (in column) Reply: Thank you for the valuable suggestions. We have revised our manuscript according to the reviewer s suggestions. We have revised Table 1 according to the reviewer s advice. The revised Table 1 is as follows: Characteristics Table 1 Basic characteristics of study HIV/AIDS patients in China (n) Total Guang dong Guang xi He nan Heilong jiang Hu nan Jiang xi Shaan xi Shang Number of patients Age, years Sex Mean age Male Female HIV transmission category Sexual contact IDU Blood transfusion Unknown CD4 count, cells/mm 3 < Median CD4 count Ethnicity Han Zhuang Uygur Other IDU: Intravenous drug use hai Xin jiang Yun nan 6

8 Table 2 should contain more row variables, not just age and sex. The statistics (median and IQR) should be aggregated by only one variable at a time. For each variable, the test of common median among group (KW test or Ranksum test) should be employed Reply: Thank you for the valuable suggestions. We have revised Table 1 according to the reviewer s advice. The revised Table 2 is as follows: Table 2 The median CD4 counts among study HIV/AIDS patients Cohort Median CD4 count(iqr)(cells/mm 3 ) Sex Male 81 (24, 213) Female 97 (23, 233) P value for difference Age (22, 290) (24, 234) (24, 209) (20, 189) 55 93(30, 210) P value for difference Ethnicity Han 93(25, 229) Zhuang 40(16, 127) Uygur 164(85, 263) Other 116(30, 227) P value for difference <0.001 HIV transmission category Sexual contact 67(21, 202) Intravenous drug use 163(64, 271) Blood transfusion 98(32, 209) Unknown transmission risk 70(25, 205) P value for difference <

9 Table 3 was erroneously analysed. Categorical variables such as province, ethnicity, etc were wrongly treated as continuous variables. Reply: Thank you for the valuable suggestions. We are very sorry for our mistake. we have re-written the statistical analysis section and revised Table 3 according to the Reviewers suggestions. The manuscript mainly focuses on the CD4 count at HIV diagnosis. We used t-test, rank sum test or one-way ANOVA to compare CD4 counts between different subgroups in the original manuscript. In the revised manuscript, multivariate logistic regression models were used to analyze factors associated with low CD4 count (<100/mm 3 ) at HIV diagnosis. Low CD4 count was defined as CD4 count <100/mm 3 at HIV diagnosis. By doing this, we can analyse our data by using multivariate logistic regression model (for categorical variable analysis), but not using multiple linear regression analysis( for continuous variable analysis). By using t-test, rank sum test or one-way ANOVA, and multivariate logistic regression analysis, we can analyse the immunologic status of a newly diagnosed HIV positive population in China. The revised Statistical analysis section and Table 3 are as follows: Statistical analysis SPSS software for Windows (Version 11.5; SPSS Inc., Chicago, IL) was used for statistical analysis. Data were described using median (interquartile range, IQR) and frequencies. We performed t-test, rank sum test or one-way ANOVA to compare CD4 counts between different subgroups. Multivariate logistic regression models were used to analyze factors associated with low CD4 count at HIV diagnosis. Low CD4 count was defined as CD4 count < 100/mm 3 at HIV diagnosis. Factors included in the models were province, sex, age, ethnicity and HIV transmission route. All variables included in the models were determined a priori 8

10 based on epidemiological importance and biological plausibility. The statistical test was two-tailed and performed at a level of statistical significance of Table 3 Identification of factors associated with low CD4 count at HIV diagnosis among newly diagnosed HIV/AIDS patients in China, results of the multivariate logistic regression Factor P value Odds ratio 95% Confidence interval Age,per 10-year increment (0.847, 0.980) Male sex (1.042, 1.518) Ethnicity Han Zhuang (0.683, 1.303) Uygur (0.971, 4.134) Other (0.643, 1.763) HIV transmission route Sexual contact < Blood transfusion (0.624, 1.898) Intravenous drug use < (0.405, 0.677) Unknown transmission risk (1.104, 2.088) Province Guangdong < Guangxi < (3.608, 6.972) Henan < (2.064, 9.440) Heilongjiang (1.080, 3.193) Hunan (0.801, 1.903) Jiangxi < (3.314, ) Shaanxi (0.223, 0.750) Shanghai < (1.574, 3.219) Xinjiang (0.778, 1.909) Yunnan < (1.353, 2.713) 9