Characteristics of included studies [ordered by study ID]
Brown 2004
|
| Methods | Cohort of HIV-1 infected subjects in Entebbe, Uganda. All subjects had duplicate Kato-Katz smears, modified formol-ether concentrations and charcoal cultures performed on stool samples. ELISA for circulating anodic antigen (CAA) of Schistosoma mansoni was performed on serum samples. Subjects were also screened for microfilaria and Wuchereria bancrofti. All subjects were followed one month after enrollment and at their routine 6 month visit. |
|
| | Participants | Adults attending the AIDS Support Organization Clinic of the UK Medical Research Council Entebbe Cohort in Entebbe, Uganda. 663 subjects were recruited and this analysis included data on the 177 subjects who had available CD4 counts from 6 months prior to enrollment, enrollment and the 6 month follow up visit. |
|
| | Interventions | All subjects received albendazole 400mg directly observed at enrollment. Those participants found to be infected with schistosomes were treated with a single dose of praziquantel 40mg/kg. |
|
| | Outcomes | The effect of helminth infection and treatment on changes in CD4 count and HIV-1 RNA in HIV-1 infected participants. |
|
| | Notes | This study used data from the same cohort as the Elliott 2003 study.
The >20% drop out rate seen in this study reflects 58 individuals who did not provide sufficient stool for charcoal culture (to determine Strongyloides infection). The excluded subjects did not significantly differ at baseline from the included subjects.
Additional CD4 and HIV-1 RNA data were provided by the authors. |
|
| | Risk of bias |
| | Item | Authors' judgement | Description |
| | Allocation concealment? | Unclear | D - Not used |
|
|
Elliott 2003
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| Methods | Cohort study of HIV-1 seropositive subjects in Uganda. Subjects attending routine appointments were recruited. All subjects had stool samples examined using Kato-Katz method for helminths and underwent serum ELISA for circulating anodic antigen (CAA) for detection of Schistosoma mansoni. All subjects were followed at 5 weeks and 4 months after enrollment. |
|
| | Participants | Adults attending the AIDS Support Organization Clinic of the UK Medical Research Council Entebbe Cohort in Entebbe, Uganda. 120 HIV-1 seropositive individuals were enrolled and 39 HIV-1 and helminth co-infected individuals were included in this analysis. |
|
| | Interventions | Nematode infected individuals were treated with mebendazole 100mg twice a day for three days and schistosomiasis was treated with two doses of 20mg/kg of praziquantel. |
|
| | Outcomes | Change in CD4 count in the 6 months prior to treatment compared to change in CD4 count between enrollment and the 4 month follow up visit. |
|
| | Notes | This study used data from the same cohort as the Brown 2004 study.
The retrospective comparison of CD4 data was not included in the paper but the unpublished data were provided by the authors. |
|
| | Risk of bias |
| | Item | Authors' judgement | Description |
| | Allocation concealment? | Unclear | D - Not used |
|
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Kallestrup 2005
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| Methods | Randomized, unblinded, controlled trial of immediate versus delayed (at 3 months) therapy of schistosomiasis. Patients with and without HIV-1 infection who were found to be infected with schistosomes were randomized to receive praziquantel at enrollment or after a delay of three months. Data from the HIV-1 seropositive cohort are included in this analysis. |
|
| | Participants | Adult participants were recruited through community meetings in rural Zimbabwe. 287 individuals were enrolled of whom 130 with HIV-1 and schistosome co-infection were included in this analysis. 64 participants received early treatment and 66 received delayed treatment. |
|
| | Interventions | Participants received praziquantel 40mg/kg either at enrollment of after a delay of 3 months. |
|
| | Outcomes | Changes in plasma HIV-1 RNA levels and CD4 count between individuals randomized to early versus delayed treatment (3 months later). |
|
| | Notes | Unblinded RCT conducted in rural Zimbabwe. Randomization method not specified and no allocation concealment. |
|
| | Risk of bias |
| | Item | Authors' judgement | Description |
| | Allocation concealment? | No | C - Inadequate |
|
|
Modjarrad 2005
|
| Methods | Prospective cohort trial examining the impact of antihelminthic treatment on HIV-1 RNA concentrations in Zambia. The primary objective of the study was to assess differences in HIV-1 RNA levels between HIV-1 and helminth co-infected individuals who were treated with anti-helminthics and HIV-1 infected, helminth uninfected individuals who did not receive antihelminthics. |
|
| | Participants | The investigators screened 428 adults for HIV-1 serostatus and assessed helminth infection using stool microscopy. 54 HIV-1/helminth co-infected individuals were recruited into the study and matched by sex and age (±4yrs) with HIV-1 infected, helminth uninfected participants. |
|
| | Interventions | Co-infected individuals were treated at week 1 and week 4 following enrolment with albendazole (400mg on the first day and 200mg for 2 subsequent days) and praziquantel 40mg/kg divided into 2 doses given 4-6 hours apart). HIV-1 infected, helminth uninfected individuals were not treated. |
|
| | Outcomes | Co-infected individuals were treated at week 1 and week 4 following enrolment with albendazole (400mg on the first day and 200mg for 2 subsequent days) and praziquantel 40mg/kg divided into 2 doses given 4-6 hours apart). HIV-1 infected, helminth uninfected individuals were not treated. |
|
| | Notes | Not all participants received anti-helminthic therapy. |
|
| | Risk of bias |
| | Item | Authors' judgement | Description |
| | Allocation concealment? | Unclear | D - Not used |
|
|
Wolday 2002
|
| Methods | Prospective cohort trial of HIV-1 infected individuals in Ethiopia. Participants were treated regardless of stool study findings at enrollment and at 3 and 6 months of follow up. Two stool samples collected at least 4 hours apart were screened using Kato-Katz technique and by formalin-ether concentration. Six smears were prepared from each stool sample. Participants were followed up at 3 and 6 months visits following enrollment. |
|
| | Participants | 56 consecutive ambulatory asymptomatic HIV infected subjects in Ethiopia were recruited. All subjects were asymptomatic and had never taken antiretrovirals. At baseline, 31 individuals had helminth infection with one or more species. |
|
| | Interventions | All participants were treated at enrollment and at the 3 and 6 month follow up visit with 200mg per day of albendazole for 3 days. Those found on stool examination to have schistosomiasis were also were treated with 40mg/kg of praziquantel. |
|
| | Outcomes | Participants were followed at 3 and 6 months following enrollment. HIV-1 RNA and CD4 counts were measured at baseline and at the 3 month and 6 month follow up visits. |
|
| | Notes | HIV RNA measurements were available at enrollment and the 6 month follow up visit for only 28 individuals (50%). Comparisons were made between the groups infected at baseline and helminth uninfected individuals as well as between those infected at baseline who were helminth negative at follow up and those who remained helminth infected at follow up. |
|
| | Risk of bias |
| | Item | Authors' judgement | Description |
| | Allocation concealment? | Unclear | D - Not used |
|
|
Characteristics of excluded studies [ordered by study ID]
|
| Study | Reason for exclusion |
|---|
| | Brown 2005 | No comparator group. All patients treated with albendazole prior to enrollment and then those with schistosomiasis treated with praziquantel at enrollment. No data on changes prior to treatment (other than the 1 month prior after treatment with albendazole) presented. No uninfected or infected and untreated comparator group available. |
| | Gallagher 2005 | No data on maternal viral load, CD4 or clinical progression were available. The authors were contacted and stated that these data were not collected. |
| | Ganley-Leal 2006 | No data on CD4, HIV-1 RNA or clinical progression after treatment of schistosomiasis were presented. |
| | Hosseinipour 2007 | Individuals with both protozoal and helminth infection included. Follow up was only conducted on treated individuals, no data available for comparison in change in CD4 or HIV-1 RNA between treated and untreated or helminth infected and helminth uninfected comparator groups. |
| | Kallestrup 2006 | This manuscript presents further analyses using data already presented in Kallestrup 2005. |
| | Kassu 2003 | Authors report changes in CD4 counts in a group treated for helminths but do not specify treatments. Control group is a group of participants who were uninfected initially but developed infection in the 6 months prior to repeat testing. No data on standard deviation of CD4 results available and not enough information provided to calculate. |
| | Kelly 1996 | This study did not perform any testing to confirm the presence of helminth infection. In addition, outcome data did not include HIV-1 RNA, CD4 counts or markers of clinical progression. |
| | Lawn 2000 | No comparison group. Participants enrolled and treated. Changes in HIV-1 RNA and CD4 then recorded over time. No information presented on differences in outcome measures between successfully treated individuals and those who were not successfully cured of schistosomiasis or who were re-infected. |
| | McElroy 2005 | This study compared CD4 and Viral load in HIV-1 infected individuals with and without schistomiasis infection. Participants did not receive any intervention as part of this analysis and so were not assessed before and after treatment of helminths. |
| | Mwanakasale 2003 | This manuscript did not report changes in CD4 counts, HIV-1 RNA levels or clinical progresssion markers. |
|
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Characteristics of ongoing studies [ordered by study ID]
Walson
|
| Trial name or title | Treatment of helminth co-infection; short term effects of HIV-1 progression markers and immune activation |
| | Methods | |
| | Participants | HIV-1 sero-positive adults with documented helminth co-infection (hookworm, ascaris, trichuris or strongyloides), not requiring or taking antiretroviral therapy |
| | Interventions | Albenadazole 400mg per day for three days versus placebo |
| | Outcomes | CD4 count, HIV-1 RNA, immune activation markers, genital HIV-1 RNA |
| | Starting date | March 2006 |
| | Contact information | |
| | Notes | |
|
|
Comparison 1. Viral Load
|
| Outcome or subgroup title | No. of studies | No. of participants | Statistical method | Effect size |
|---|
| | 1 Change in Log10 HIV-1 RNA after antihelminth treatment or no treament | 5 | | Std. Mean Difference (IV, Fixed, 95% CI) | Totals not selected |
| | | 1 | | Std. Mean Difference (IV, Fixed, 95% CI) | Not estimable |
| | | 3 | | Std. Mean Difference (IV, Fixed, 95% CI) | Not estimable |
| | | 3 | | Std. Mean Difference (IV, Fixed, 95% CI) | Not estimable |
|
|
Comparison 2. CD4 Count
|
| Outcome or subgroup title | No. of studies | No. of participants | Statistical method | Effect size |
|---|
| | 1 Decline in CD4 count after treatment of helminth co-infection | 4 | | Std. Mean Difference (IV, Fixed, 95% CI) | Totals not selected |
| | | 1 | | Std. Mean Difference (IV, Fixed, 95% CI) | Not estimable |
| | | 3 | | Std. Mean Difference (IV, Fixed, 95% CI) | Not estimable |
| | | 2 | | Std. Mean Difference (IV, Fixed, 95% CI) | Not estimable |
| | | 2 | | Std. Mean Difference (IV, Fixed, 95% CI) | Not estimable |
|
|
Comparison 3. Mortality differences
Table 1. Assessment of quality of cohort studies
|
| Study | External Validity | Performance Bias | Detection Bias | Attrition Bias | Selection Bias |
| | Description of assessment criteria | How was sampling conducted (census, random, etc.) and were at least 80% of those eligible to participate in all groups recruited? | Was the same method of ascertainment used in cases and controls? | How were HIV-1 and helminth infection status ascertained and confirmed and were assessors of outcome measures blinded to intervention groups? | Were all groups followed for the same time frame and were at least 80% of participants in all groups included in the final analysis? | How were cases selected and were controls selected from the same population as the cases? |
| | Brown 2004 | ** | ** | | | |
| | Elliott 2003 | ** | ** | ** | ** | |
| | Wolday 2002 | ** | ** | ** | | |
| | Modjarrad 2005 | ** | ** | | ** | |
| | ** study design adequate to minimize role of bias | | | | | |
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