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ICRC-Models / HHCoM

Compartmental model of HIV and HPV heterosexual transmission, development of AIDS and cervical cancer, and interventions
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Rethink age trends in precancer progression and regression rates #94

Open carajbro opened 4 years ago

carajbro commented 4 years ago

Currently precancer progression and regression/clearance rates differ by broad age groups. This is based on transition rate age trends from CCNSW. However, recent evidence may suggest no difference in progression/regression rates by age. This needs a thorough literature review and model revision should be considered based on the conclusion.

carajbro commented 4 years ago

Had trouble simultaneously fitting the age trends in female HPV prevalence, CIN2/3 prevalence, and cervical cancer incidence. Trends: -Female HPV prevalence declines with age but increases again somewhat in older ages -CIN2/3 prevalence peaks later than HPV prevalence, but then declines with age -CC incidence increases with age Issues: -Capturing the increase in HPV prevalence in later ages leads to higher CIN2/3 prevalence in later ages -Removing the CIN progression/regression multipliers by age leads to good fits to the CIN2/3 prevalence observed data, but a peak and then decreasing trend with age in CC incidence. Could not fit the CC incidence age trend without the multipliers.

carajbro commented 4 years ago

Although this is not reflected in the CCNSW data, should we change CIN1 --> HPV and CIN2 --> CIN1 regression multipliers to be different by age rather = 1? Would this improve fit to CIN2/3 prevalence? Adding in these multipliers by age would follow the logic of having multipliers on the other transitions as a proxy for persistence since there is less heterogeneity in our compartmental model.

carajbro commented 4 years ago

In 22Apr20Ph2V2calib, we removed additional progression/regression multipliers for ages 70+. Thought is that women are unlikely to have an infection acquired in early age persist to age 70.

Also note that our assumptions about the multipliers in this age group will affect predictions, particularly by HIV status (if CC incidence is falsely high in oldest ages). If this is the case, ART will lead to increased risk is older ages where there is a competing risk due to HIV-associated mortality.