Cost effectiveness of strategies for cervical cancer prevention in India
The establishment of link between high-risk human papillomavirus (HPV) infection and occurrence of cervical cancer has resulted in development of various HPV related control strategies for the prevention of cervical cancer. The objective of the present study was to assess the cost effectiveness of various screening strategies for cervical cancer and human papilloma virus (HPV) vaccination in India. A Markov model based on societal perspective was designed to estimate the lifetime costs and consequences of screening (with either visual inspect with acetic acid (VIA), Papanicolaou test or HPV DNA test at various time intervals) in a hypothetical cohort of 30-65 years age women or vaccination among adolescent girls. Diagnostic accuracy of the screening strategies, efficacy of HPV vaccination and data on transition probabilities was based on the results of the existing meta-analyses. Primary data was collected for assessing per person cost of screening, cost of treating cervical cancer and quality of life. We found that introduction of different screening strategies leads to reduction in lifetime occurrence of cervical cancer cases caused by HPV 16/18 from 20% to 61%, and cervical cancer deaths from 28% to 70%, as compared to no screening. Among various screening strategies, screening with both VIA 5 yearly and VIA 10 yearly came out to be cost effective at 1-time per capita GDP, with VIA every 5 years providing greater health benefits as compared to VIA 10 years. Hence, screening with VIA 5 years at an incremental cost of US$ 829 (INR 54,881) per QALY gained is the recommended strategy for India. Further, with regards to HPV vaccination, it leads to 60% reduction in cancer cases and mortality caused by HPV 16/18 as compared to no vaccination. Moreover, when this vaccinated cohort of adolescent girls is also screened later in their life (with VIA every 10 years and VIA 5 years), it leads to 69%-76% reduction in cancer cases and 71%-81% reduction in cancer deaths. As compared to no vaccination and no screening, both HPV vaccination alone and vaccination plus screening (with VIA every 5 yearly and VIA 10 yearly) appears to be cost effective with ICERs in the range of US$ 86 (INR 5,693) to US$ 476 (INR 31,511) per QALY gained. In the long run, when the cohort of adolescent girls, who were immunized for HPV, reach the age of 30 years, the screening frequency using VIA should be determined based on the coverage of HPV vaccination in that cohort.
