Association between social psychological status and efavirenz and nevirapine plasma concentration among HIV patients in Kenya

HIV-related stigma, lack of disclosure and social support are still hindrances to HIV testing, care, and prevention. We assessed the association of these social-psychological statuses with nevirapine (NVP) and efavirenz (EFV) plasma concentrations among HIV patients in Kenya. Blood samples were obtained from 254 and 312 consenting HIV patients on NVP- and EFV-based first-line antiretroviral therapy (ART), respectively, and a detailed structured questionnaire was administered. The ARV plasma concentration was measured by liquid chromatography-tandem mass spectrometry (LC–MS/MS). There were 68.1% and 65.4% of the patients on NVP and EFV, respectively, who did not feel guilty for being HIV positive. The disclosure rates were approximately 96.1% and 94.6% of patients on NVP and EFV, respectively. Approximately 85% and 78.2% of patients on NVP and EFV, respectively, received social support as much as needed. There were 54.3% and 14.2% compared to 31.7% and 4.5% patients on NVP and EFV, respectively, with supratherapeutic and suboptimal plasma concentrations. Multivariate quantile regression analysis showed that feeling guilty for being HIV positive was associated with increased 954 ng/mL NVP plasma concentrations (95% CI 192.7 to 2156.6; p = 0.014) but not associated with EFV plasma concentrations (adjusted β = 347.7, 95% CI = − 153.4 to 848.7; p = 0.173). Feeling worthless for being HIV positive was associated with increased NVP plasma concentrations (adjusted β = 852, 95% CI = 64.3 to 1639.7; p = 0.034) and not with EFV plasma concentrations (adjusted β = − 143.3, 95% CI = − 759.2 to 472.5; p = 0.647). Being certain of telling the primary sexual partner about HIV-positive status was associated with increased EFV plasma concentrations (adjusted β 363, 95% CI, 97.9 to 628.1; p = 0.007) but not with NVP plasma concentrations (adjusted β = 341.5, 95% CI = − 1357 to 2040; p = 0.692). Disclosing HIV status to neighbors was associated with increased NVP plasma concentrations (adjusted β = 1731, 95% CI = 376 to 3086; p = 0.012) but not with EFV plasma concentrations (adjusted β = − 251, 95% CI = − 1714.1 to 1212.1; p = 0.736). Obtaining transportation to the hospital whenever needed was associated with a reduction in NVP plasma concentrations (adjusted β = − 1143.3, 95% CI = − 1914.3 to − 372.4; p = 0.004) but not with EFV plasma concentrations (adjusted β = − 6.6, 95% CI = − 377.8 to 364.7; p = 0.972). HIV stigma, lack disclosure and inadequate social support are still experienced by HIV-infected patients in Kenya. A significant proportion of patients receiving the NVP-based regimen had supra- and subtherapeutic plasma concentrations compared to EFV. Social-psychological factors negatively impact adherence and are associated with increased NVP plasma concentration compared to EFV.