Hanne Zimmermann

Hanne Zimmermann


Research Focus & Metrics

Academic Career Length

8Years (2019-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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14 October 2019 in Journal of the International AIDS Society
Verified
Journal Article
Open access
PDF file
HZHanne Zimmermann
Hanne Zimmermann
SESanne W Eekman
Sanne W Eekman
RARoel Ca Achterbergh
Roel Ca Achterbergh
MLMaarten F Schim van der Loeff
Maarten F Schim van der Loeff
MPMaria Prins
Maria Prins
O(On behalf of the Amsterdam PrEP Project team in the HIV Transmission Elimination AMsterdam Consortium (H‐TEAM)
On behalf of the Amsterdam PrEP Project team in the HIV Transmission Elimination AMsterdam Consortium (H‐TEAM)
Introduction: In settings where both daily and event‐driven pre‐exposure prophylaxis (PrEP) are offered to men who have sex with men (MSM), a clear understanding of the motives to choose between the different dosing‐regimens can facilitate more effective PrEP implementation. We therefore studied the motives for choosing for, switching between, and stopping daily or event‐driven PrEP.Methods: We used data (August 2015‐June 2017) from the prospective, longitudinal, open‐label Amsterdam PrEP demonstration study, in which daily (dPrEP) and event‐driven PrEP (edPrEP) were offered to 374 HIV‐negative MSM and two transgender persons. Participants self‐selected the preferred PrEP‐regimen at baseline and could switch regimens at three‐monthly follow‐up visits. We measured motives for choosing PrEP‐regimen at baseline and for switching and stopping PrEP at follow‐up visits. Open‐ and closed‐end items were combined and qualitatively analysed.Results: Choices of PrEP‐regimens were determined by personal and contextual factors, involving the perceived self‐efficacy concerning adherence, the risk‐context, and the anticipated impact of PrEP on physical and sexual wellbeing. dPrEP was preferred because of the anticipated better adherence and the fear of side‐effects relating to edPrEP re‐initiations. Moreover, dPrEP was perceived to be more effective than edPrEP. Motives to choose edPrEP were the expected physical burden of dPrEP, anticipated side‐effects of dPrEP, and fear to forget daily doses. Regarding the risk‐context: dPrEP was preferred for unplanned and/or frequent sex, while edPrEP was chosen when risk was predictable and/or less frequent. While some chose for dPrEP to gain more sexual freedom, others chose for edPrEP to minimize sexual risk episodes. Changes in the above factors, such as changing risk patterns, changing relationships or changing physical conditions, resulted in switching regimens. Choices to stop PrEP were related to lower sexual risk, adherence issues and side‐effects.Conclusions: The great diversity of motives illustrates the importance of offering a choice of PrEP‐regimens. In counselling of MSM starting PrEP, choices for PrEP‐regimens may be addressed as a continuum of flexible and changeable options over time. This may help individuals choose the PrEP‐regimen that best fits their current sexual context, priorities and personal capabilities and therefore will be more easily adhered to.

1 March 2021 in JAIDS Journal of Acquired Immune Deficiency Syndromes
Verified
Journal Article
Closed access
WBWard P. H. van Bilsen
Ward P. H. van Bilsen
HZHanne Zimmermann
Hanne Zimmermann
ABAnders Boyd
Anders Boyd
Liza CoyerLiza Coyer
Liza Coyer
LHLia Van der Hoek
Lia Van der Hoek
AMAmy Matser
Amy Matser
Objective: To investigate the impact of Dutch COVID-19 restrictions on sexual behavior and HIV/sexually transmitted infection (STI) acquisition among men who have sex with men (MSM) participating in the Amsterdam Cohort Studies (ACS) on HIV in Amsterdam. Methods: ACS participants complete a questionnaire on sexual behavior and are tested for HIV/STI biannually. They may also be tested at the STI clinic in-between study visits. On May 29, 2020, ACS participants were invited to complete an online questionnaire on health, COVID-19 risk perceptions, and sexual behavior. Determinants of reporting casual sex partners (CSP) during COVID-19 restrictions were examined using logistic regression. Results: Of 683 MSM, 353 (52%; median age, 47 years; interquartile range, 38–53 years) completed the questionnaire. Since COVID-19, 73% reported a reduction in the number of CSP. CSP during COVID-19 restrictions were reported by 133 MSM (38%) and, in multivariable analysis, was associated with not having a college/university degree, being single, lower perceived importance of avoiding COVID-19, number of CSP before COVID-19, and current preexposure prophylaxis use (P < 0.05 for all). During COVID-19 restrictions, no HIV infections were diagnosed, and the STI positivity rate was 8%. Conclusion: Since COVID-19, the number of CSP decreased among MSM, and there may have been a temporary reduction in HIV/STI transmission. Some MSM were not fully compliant to social distancing regulations and reported CSP, which was related to prior sexual behavior and low perceived importance of avoiding COVID-19. For these men, it is important to maintain accessible HIV/STI-related testing and care during times of lockdown.

18 August 2022 in Eurosurveillance
Verified
Journal Article
Open access
HWHaoyi Wang
Haoyi Wang
KPKennedy J.I. D'Abreu de Paulo
Kennedy J.I. D'Abreu de Paulo
TGThomas Gültzow
Thomas Gültzow
HZHanne Zimmermann
Hanne Zimmermann
Kai J. JonasKai J. Jonas
Kai J. Jonas
Monkeypox is a zoonotic disease and leads to a smallpox-like disease in humans. The current epidemic in European countries requires informed responses. We investigated the ability to self-diagnose a potential infection, and determinants of vaccination and self-isolation intention after diagnosis among 394 MSM in the Netherlands. We found that about half were able to self-diagnose monkeypox, that 70% had a high intention to get vaccinated and 44% to self-isolate after monkeypox diagnosis. Determinants went beyond mere risk behaviour criteria.

12 August 2021 in Journal of the International AIDS Society
Verified
Journal Article
Open access
PDF file
VJVita W Jongen
Vita W Jongen
TRThijs Reyniers
Thijs Reyniers
ZYZorah Mh Ypma
Zorah Mh Ypma
MLMaarten F Schim van der Loeff
Maarten F Schim van der Loeff
UDUdi Davidovich
Udi Davidovich
EHElske Hoornenborg
Elske Hoornenborg
Introduction: Daily and event‐driven PrEP are both efficacious in reducing the risk for HIV infection. However, the practice of event‐driven PrEP (edPrEP) is less well studied, in particular when provided as an alternative to daily PrEP. We studied regimen preferences and switches, and sexually transmitted infection (STI) incidence.Methods: We analysed pooled data from two prospective cohort studies among MSM: Be‐PrEP‐ared, Belgium and AMPrEP, the Netherlands. In both projects, participants could choose between daily and edPrEP at three‐monthly study visits, when they were also screened for sexually transmitted infections including hepatitis C (HCV). We assessed the proportion choosing each regimen, and the determinants of choosing edPrEP at baseline. Additionally, we compared the incidence rates (IRs) of HCV, syphilis and chlamydia or gonorrhoea between regimens using Poisson regression. The study period was from 3 August 2015 until 24 September 2018.Results and discussion: We included 571 MSM, of whom 148 (25.9%) chose edPrEP at baseline. 31.7% of participants switched regimen at least once. After 28 months, 23.5% used edPrEP. Older participants (adjusted odds ratio (aOR) = 1.38 per 10 years, 95% confidence interval (CI) = 1.15 to 1.64) and those unemployed (aOR = 1.68, 95% CI = 1.03 to 1.75) were more likely to initially choose edPrEP. IR of HCV and syphilis did not differ between regimens, but the IR of chlamydia/gonorrhoea was higher among daily users (adjusted incidence rate ratio = 1.61, 95% CI = 1.35 to 1.94).Conclusions: A quarter of participants chose edPrEP at baseline and at 28 months this proportion was similar. Although the IR of HCV and syphilis were similar in the two regimens, the lower incidence of chlamydia and gonorrhoea among edPrEP users may suggest that less frequent STI testing of this group could be considered.

15 August 2021 in JAIDS Journal of Acquired Immune Deficiency Syndromes
Verified
Journal Article
Open access
VJVita W. Jongen
Vita W. Jongen
HZHanne Zimmermann
Hanne Zimmermann
ABAnders Boyd
Anders Boyd
EHElske Hoornenborg
Elske Hoornenborg
MEMark A. M. van Den Elshout
Mark A. M. van Den Elshout
OIon behalf of the Amsterdam PrEP Project team in the HIV Transmission Elimination Amsterdam Initiative
on behalf of the Amsterdam PrEP Project team in the HIV Transmission Elimination Amsterdam Initiative
Background: We assessed how the Dutch restrictions imposed on March 15, 2020, affected sexual behavior, preexposure prophylaxis (PrEP), and condom use among PrEP users in Amsterdam. Methods: We used data on (1) PrEP use, (2) anal sex acts, and (3) condom use, per partner type [steady partners (SPs), known casual partners (KCPs), and unknown casual partners (UCPs)], collected daily through a mobile application used between December 1, 2019, and June 30, 2020. We compared the period before versus after March 15, 2020, regarding average proportion of days per week at which each end point was reported and average proportion of anal sex acts covered by PrEP and/or condoms. Results: We included data from 136 men who have sex with men. After March 15, 2020, the proportion of days with anal sex increased with SPs [odds ratio (OR) = 1.26; 95% confidence interval (CI) = 1.10 to 1.44) and decreased with KCPs (OR = 0.73; 95% CI = 0.64 to 0.82) and UCPs (OR = 0.54; 95% CI = 0.48 to 0.61). Shifts in partner types were most profound immediately after March 15, 2020, whereas returning to prerestriction levels mid-May 2020. The proportion of days with PrEP use decreased from 74% before to 58% after March 15, 2020 (P < 0.001). After March 15, 2020, PrEP use during sex decreased with UCPs (β = −0.36; 95% CI = −0.72 to 0.00) but not with SPs and KCPs. Condom use during sex decreased with KCPs (β = −0.36; 95% CI = −0.67 to 0.04) and UCPs (β = −0.24; 95% CI = −0.46 to 0.03) but not with SPs. Conclusions: MSM decreased sex with casual partners and increased sex with SP, but changes were transient. Decreases in sex acts with casual partners paralleled decreases in PrEP use. However, condom use during sex with casual partners decreased, indicating the importance of continued sexual health services, including sexually transmitted infections screening and PrEP care, during COVID-19 restrictions.

10 May 2021 in Journal of the International AIDS Society
Verified
Journal Article
Open access
PDF file
VJVita W Jongen
Vita W Jongen
EHElske Hoornenborg
Elske Hoornenborg
MEMark Am van Den Elshout
Mark Am van Den Elshout
ABAnders Boyd
Anders Boyd
HZHanne Zimmermann
Hanne Zimmermann
TIthe Amsterdam PrEP Project team in the HIV Transmission Elimination Amsterdam (H‐TEAM) Initiative
the Amsterdam PrEP Project team in the HIV Transmission Elimination Amsterdam (H‐TEAM) Initiative
Introduction: Event‐driven pre‐exposure prophylaxis (edPrEP) with oral tenofovir disoproxil fumarate (TDF)/emtricitabine (FTC) is highly effective for preventing HIV acquisition in men who have sex with men (MSM) and is preferred over daily PrEP by some MSM. However, it is largely unknown how well MSM adhere to edPrEP. We then aimed to assess PrEP protection during CAS among MSM using edPrEP and participating in the Amsterdam PrEP demonstration project (AMPrEP).Methods: We analysed data from participants enrolled in AMPrEP who were taking edPrEP. We measured adherence through (1) a mobile application in which sexual behaviour and PrEP‐use were recorded daily, (2) three‐monthly self‐completed questionnaires and (3) dried blood spot (DBS) samples collected around six, twelve and twenty‐four months after PrEP initiation. We assessed the proportion of days with condomless anal sex (CAS) acts that were protected by PrEP, per partner type (i.e. steady partners, known casual partners, unknown casual partners), and the proportion of three‐month periods during which PrEP was correctly used. Intracellular TFV‐diphosphate (TFV‐DP) concentrations were determined from DBS. Good adherence was defined as at least one tablet before and one tablet within 48 hours after a CAS act.Results: Between 11 September 2015 and 6 October 2019, 182 of 376 MSM (48.4%) used edPrEP for at least one three‐month period. Of the 8224 CAS days that were reported in the app during edPrEP‐use, we observed good protection for most CAS days involving steady partners (n = 1625/2455, 66.9%), known casual partners (n = 3216/3472, 92.6%) and unknown casual partners (n = 2074/2297, 90.3%). Men reported consistently correct PrEP‐use in 851 (81.4%) of the 1046 three‐month periods of edPrEP‐use. The median TFV‐DP concentration was 591 fmol/sample (interquartile range = 270 to 896).Conclusions: Adherence to edPrEP was high as determined from the online app and questionnaire. DBS measurements were consistent with two to three tablets per week on average.