Performance of the patient health questionnaire and Edinburgh postnatal depression scale as screening tools for antepartum depression.

Abstract

Background: Depression during pregnancy or antepartum depression (APD) is a condition of great public health concern with a high prevalence globally and locally. It has also been shown to lead to postpartum depression and other adverse sequelae such as preeclampsia and low birth weight and prematurity. The availability of APD screening tools whose accuracy has been tested in our population is key in informing APD surveillance and developing local guidelines for its clinical management. The Patient Health Questionnaire-9 (PHQ-9) and Edinburgh Postnatal Depression Scale (EPDS) are APD screening tools both of which are short and easy to use but whose performance in the Kenyan population has not been adequately studied. Study objective: The broad objective of the study was to assess the performance of the Patient Health Questionnaire-9 and the Edinburgh Postnatal Depression Scale as screening tools for antepartum depression in Nairobi county and Karatina sub-county. Methodology: A cross-sectional study was carried out where 263 and 220 pregnant women from Mutuini Hospital (MH) and Karatina Sub-county Hospital (KSCH) respectively who were 18 years and above of age, had no known medical history of mental illness, HIV, Diabetes or Hypertension and were not bereaved within a period of six months before the time of the interview were screened for APD using both the PHQ-9 and EPDS. A separate study questionnaire was also utilised to gather additional data on participants’ sociodemographic factors. A Bayesian Latent Class Model (BLCM) was applied to the participants' cumulative scores gotten from the two APD screening tools.2 Results: The sensitivity (Se) and specificity (Sp) measures of both PHQ-9 and EPDS were optimized at cut-off values of ≥15 and ≥9 respectively. Both tests recorded very low Se (0.3%, 95% posterior credibility interval [PCI] [0.01, 1.2] for PHQ-9 and 5.2%, 95% PCI [0.4, 9.4] for EPDS) and Sp (63.2%, 95% PCI [7.5, 86.4] for PHQ-9 and 12.3%, 95% PCI [0.6, 42.1] for EPDS). The negative and positive predictive values for both tests were generally low across the two study populations. The posterior median APD prevalence in Karatina and Mutuini was 95.4 % (95% PCI 87.6, 99.1) and 93.1% (95% PCI 85.1, 97.1) respectively with no statistically significant difference between them. Conclusion: In low resource settings, the PHQ-9 and EPDS perform poorly in APD screening. Their use should be supplemented by mental state examinations from trained mental healthcare workers who thus should be availed at low level healthcare facilities. Based on the high true prevalence of APD, deliberate screening for the same is crucial and should be incorporated into the routine ANC package.