The Trend and Prediction of Cervical Cancer Incidence in Delhi, India: An Age-Period-Cohort Analysis

The objective of the study is to assess the trend of age-standardised incidence rate (ASIRs) of cervical cancer, standardised median age at diagnosis, and projection of cervical cancer incidence rate and the number of new cases up to 2030. The projections help in making strategies for resource allocation to circumvent the future burden.

The data were extracted from the Delhi population-based cancer registry from 1990 to 2014. Joinpoint regression analysis was applied to ASIRs to assess the trend. The natural cubic splines age-period-cohort (APC) model was fitted to project the incidence rate and incidence cases. The trend of standardised median age at diagnosis and percentage of cervical cancer to total women cancer was also assessed using regression analysis. Projections of new cases are decomposed into three components aging, the structure of the population, and age-specific incidence rate.

The age-standardised incidence rate of cervical cancer decreased with an annual decline at a rate of 2.98% (95% CI -3.48 to -2.47) from 1990 to 2014. The standardised median age at diagnosis showed an upward trend with an average annual increase of 0.167 per year and the median age increased by 4.18 years during 25-years period, this change was due to the shifting of the peak from 40-44 in 1990 to 60-64 in 2014. The APC model revealed ASIRs would decline by 43.8% in 2030 compared to average ASIRs 2010-2014, albeit a net 12% increase in the incidence cases. An increase in incidence cases is primarily attributed to the aging of the population and population  growth by 38.87% and 33.84% respectively.  The trend analysis of  cervical cancer ASIRs in pre (< 50 years) and post menopause (≥ 50 years) showed a decreasing trend. However, the ratio of cervical to total women increased over time from 1:1 in 1990 to 2:3 in 2014.

The declining trend in ASIRs was observed in Delhi and will continue to decrease up to 2030.  The burden of the number of new cases of cervical cancer showed an upward trend primarily due to the aging of the population and shifting of population structure. To counter this big challenge a cost-effective vaccination for vulnerable populations, community-based screening programs, and awareness about cervical cancer prevention might help in eliminating this preventable cancer.