Methods: This was a prospective cross-sectional study. A total of 3303 subjects aged 40 years and above from two large population-based cohorts, the Singapore Malay Eye Study-2 (n = 1191, 2011-2013) and the Singapore Indian Eye Study-2 (n = 2112, 2013-2015), were included. The presence of symptoms of dry eye was defined as having at least one of six symptoms often or all the time. Sleep questionnaires included the Epworth Sleepiness Scale, Berlin Questionnaire, STOP-bang questionnaire, and Insomnia Severity Index. Poor sleep quality was defined as meeting the respective questionnaire thresholds. General health questionnaires (including sleep duration) and standardized ocular and systemic tests were also used.

Results: Of 3303 participants, 6.4% had excessive sleepiness, 20.5% had high risk for sleep apnea, 2.7% had clinical insomnia, and 7.8% had <5 hours of sleep. These sleep factors were associated with symptoms of dry eye. After adjusting for relevant demographic, medical, and social factors, the following were associated with higher odds of symptoms of dry eye: excessive sleepiness (Epworth Sleepiness Scale: odds ratio [OR] = 1.77 [1.15-2.71]), high risk of sleep apnea (Berlin Questionnaire: OR = 1.55 [1.17-2.07], STOP-Bang Questionnaire: OR = 2.66 [1.53-4.61]), clinical insomnia (Insomnia Severity Index: OR = 3.68 [2.17-6.26]) and <5 hours of sleep (OR = 1.73 [1.17-2.57], reference sleep duration 5-9 hours). Sleep apnea, insomnia, and sleep duration were each shown to be independently associated with symptoms of dry eye.

METHODS: Based on existing frameworks for the EMTCT for each individual infection, an integrated framework that combines infection prevention procedures with routine antenatal care was constructed. Using decision tree analyses, population impacts, cost-effectiveness and the potential reduction in required resources of the integrated approach as a result of resource pooling and improvements in service coverage and coordination, were evaluated. The tool was assessed using simulated epidemiological data from Cambodia.

RESULTS: The current prevention programme for 370,000 Cambodian pregnant women was estimated at USD$2.3 ($2.0-$2.5) million per year, including the duration of pregnancy and up to 18 months after delivery. A model estimate of current MTCT rates in Cambodia was 6.6% (6.2-7.1%) for HIV, 14.1% (13.1-15.2%) for HBV and 9.4% (9.0-9.8%) for syphilis. Integrating HIV and syphilis prevention into the existing antenatal care framework will reduce the total time required to provide this integrated care by 19% for health care workers and by 32% for pregnant women, resulting in a net saving of $380,000 per year for the EMTCT programme. This integrated approach reduces HIV and HBV MTCT to 6.1% (5.7-6.5%) and 13.0% (12.1-14.0%), respectively, and substantially reduces syphilis MCTC to 4.6% (4.3-5.0%). Further introduction of either antiviral treatment for pregnant women with high viral load of HBV, or hepatitis B immunoglobulin (HBIG) to exposed newborns, will increase the total cost of EMTCT to $4.4 ($3.6-$5.2) million and $3.3 ($2.7-$4.0) million per year, respectively, but substantially reduce HBV MTCT to 3.5% (3.2-3.8%) and 5.0% (4.6-5.5%), respectively. Combining both antiviral and HBIG treatments will further reduce HBV MTCT to 3.4% (3.1-3.7%) at an increased total cost of EMTCT of $4.5 ($3.7-$5.4) million per year. All these HBV intervention scenarios are highly cost-effective ($64-$114 per disability-adjusted life years averted) when the life benefits of these prevention measures are considered.