Adherence to and Tolerability of Three HIV Postexposure Prophylaxis (PEP) Regimens among Health Care Workers

Background:   Although the overall risk of HIV infection following occupational exposure among health care workers (HCW) is relatively low, occupational acquisition of HIV by HCW has occurred.  PEP, administration of medications active against HIV to HCW following occupational exposure to HIV or potentially infected body fluids, is the standard of care in the US.  Guidelines from public health authorities for treatment of patients living with HIV have been updated to reflect anti-retroviral regimens that show improved efficacy, fewer side effects (SE), and a reduced pill burden.  With the goals of improving the efficacy and rates of completion of a 28-day PEP course by HCW, the Mount Sinai Hospital (MSH) has periodically updated standard PEP regimens to reflect changes in treatment guidelines.

Objective: To compare adherence to and tolerability of 3 PEP regimens used for occupational exposures during 3 different time periods.

Methods: A retrospective analysis of occupational exposures at MSH for which 28 days of the standard PEP regimen was prescribed (Rx'd) during 2004, 2008-09, and 2010 (7 months) was conducted. Exposed HCW were interviewed.  Infection Control documents, case reports, and Employee Health Service records were reviewed.  A standardized data collection tool was used.

Results: The standard PEP regimen used during each of the periods is shown in the Table.  Rates of completing treatment with the standard regimen were 60%, 47% and 62% (p=0.5) during the 3 time periods, respectively.  SE were the most common reason for discontinuing standard PEP.  Rates of discontinuation due to SE ranged from 38-47% and did not differ significantly between the 3 regimens (p=0.82). SE were experienced by over 75% of HCW and over 25% had two or more SE irrespective of the PEP regimen prescribed. Gastrointestinal upset was the most common SE reported. Other SE were malaise, myalgias, headaches and laboratory abnormalities.  Thirty-three to 62% of HCW who discontinued standard PEP due to SE chose not to continue PEP with an alternative regimen. 

Year(s)	2004	2008-09	2010
Total exposures (n)	254	735	181
PEP regimen	AZT/3TC/ nelfinavir	FTC/tenofovir/ lopinavir/ritonavir	FTC/tenofovir/ atazanavir/ritonavir
# HCW prescribed 28 day  course of standard PEP	20 (8%)	45 (6%)	8 (4%)
# completed 28 d of standard PEP	12 (60%)	21 (47%)	5 (62%)
# who stopped standard PEP due to SE # who changed to alternative regimen # who declined alternative regimen	8 (40%) 3 5	21 (47%) 5 16	3 (38%) 2 1
# changed to alternate PEP due to source virus resistance	0	3	0
# completed any 28 day PEP regimen	15/20 (75%)	29/45 (64%)	7/8 (88%)

Conclusions: Despite efforts to offer PEP with improved efficacy and tolerability profiles, a substantial proportion of HCW failed to complete the recommended 28-day course of PEP.  This was almost always the result of SE.  Optimizing the tolerability of and improving HCW adherence to PEP remains an occupational health priority.