Clinical Outcomes and Treatment Adherence among Patients Receiving Care for Sexually Transmitted Infections in Primary Health Care Centres in Southern Nigeria

Abstract

Background: Treatment adherence is critical for achieving favourable clinical outcomes in sexually transmitted infection (STI) care. Studies in Nigeria have consistently identified educational attainment, marital status, and the type of STI (particularly gonorrhoea) as predictors of adherence, with adherent patients demonstrating higher symptom resolution and lower recurrence. However, evidence directly linking adherence to these clinical endpoints within primary health care centre settings in Rivers State, Southern Nigeria, remains limited. Objective: This study assessed treatment adherence and its association with clinical outcomes, namely symptom resolution, recurrence, and complications, among STI patients attending primary health care centres in two local government areas (LGAs) of Rivers State, Southern Nigeria. Methods: A facility-based analytic cross-sectional study was conducted from April to July 2026 across six primary health care centres in two LGAs (Eleme and Oyigbo). Three PHCs were randomly selected from each LGA. A total of 634 adult STI patients were recruited using multistage sampling. Data were collected using structured questionnaires and medical record reviews. Adherence was assessed by self-report and pill count. Clinical outcomes were extracted from follow-up records. Bivariate and multivariable logistic regression analyses were performed, with statistical significance set at p < 0.05. Results: The mean age was 29.4 ± 8.6 years; 47.0% were aged 20–29 years, and 58.2% (n = 369) were female. Overall treatment adherence was 52.1%. Adherence was higher among females (56.7% vs 46.2%), married participants (61.3% vs 47.8%), and tertiary-educated participants (62.4% vs 39.5%). Chi-square tests showed significant associations between adherence and education level (p<0.001), marital status (p=0.002), and sex (p=0.009). Multivariable analysis identified tertiary education (AOR=2.1, 95% CI: 1.4–3.2) and married status (AOR=1.8, 95% CI: 1.2–2.7) as positive predictors, while gonorrhoea diagnosis (AOR=0.7, 95% CI: 0.5–0.9) was a negative predictor. Among adherent patients, 81.6% achieved complete symptom resolution compared to 42.9% of non-adherent patients; recurrence was 9.3% among adherent patients versus 28.7% among non-adherent patients. Conclusion: In this population, treatment adherence was suboptimal and was independently associated with education, marital status, and gonorrhoea diagnosis. Adherent patients experienced substantially higher symptom resolution and lower recurrence. Interventions targeting less-educated, single, and gonorrhoea-diagnosed patients are needed.