Cancer incidence in urban Shanghai, 1973-2010: an updated trend and age-period-cohort effects

Abstract

Background: To provide a comprehensive overview of temporal trends in cancer incidence during 1973-2010 in urban Shanghai.

Methods: The estimated annual percent changes (EAPCs) for the whole period and for the time segments in age-standardized incidence rates (ASR) were evaluated with Joinpoint analysis. Age-period-cohort (APC) models were modeled to examine the effects of age, period and birth cohort on cancer incidence.

Results: The overall ASR decreased slightly and significantly in males (EAPC of -0.41) but increased significantly in females (EAPC of 0.57) during 1973-2010 in urban Shanghai. The incidence trend was not linear and varied by time segments. During the most recent 10 years (2001-2010), the ASR in males decreased by 1.65% per year and stabilized in females. Incidence rates continued to decline during 1973-2010 for esophagus, stomach, and liver cancer in both sexes, as well as male lung cancer and cervix cancer. It should be noted that it was the first time to document a significant decline in lung cancer incidence among males during 1973-2010 with EAPC of -0.58%, and a notable upward for cervix cancer since 1996 with EAPC of 8.94%. Unfavorable trends in incidence were observed for the most common cancer sites in the 38 years period: colorectum, gallbladder & biliary tract, pancreas, kidney, bladder, brain & central nervous system (CNS), thyroid, non-Hodgkin's lymphoma (NHL), prostate, female breast, corpus uteri, and ovary. APC analysis showed age, period and birth cohort yielded different effects by cancer sites.

Conclusions: The observed trends primarily reflect dramatic changes in socioeconomic development and lifestyles in urban Shanghai over the past four decades.

Keywords: Age-period-cohort analysis; Cancer incidence; Shanghai; Time trend.

Fig. 1

Estimated Age-Period-Cohort effects for incidence of selected cancers in urban Shanghai (1973–2010) among males Note: Age-period-cohort effects, with confidence limits, on incidence from common cancer sites in urban Shanghai. Each graph has three curves depicting, from left to right, trends in incidence rate by age for the reference cohort (age effect), incidence risk by birth cohort (cohort effect,taking 1937–1941 or 1932–1936 as the reference) and incidence risk by calendar year (period effect, taking the incidence average of the period as the reference). The graph has the horizontal axis divided into two parts: one for age (years old) and one for cohort-period (calendar years). The left vertical axis represents incidence rates for the age effect and the right vertical axis represents the relative risk for the cohort and period effect. The drift is added to the non-linear birth cohort effects and the right plot presents the period effect as residual ratio rates

Fig. 2

Estimated Age-Period-Cohort effects for incidence of selected cancers in urban Shanghai (1973–2010) among females. Note: Age-period-cohort effects, with confidence limits, on incidence from common cancer sites in urban Shanghai. Each graph has three curves depicting, from left to right, trends in incidence rate by age for the reference cohort (age effect), incidence risk by birth cohort (cohort effect, taking 1937–1941 or 1932–1936 as the reference) and incidence risk by calendar year (period effect, taking the incidence average of the period as the reference). The graph has the horizontal axis divided into two parts: one for age (years old) and one for cohort-period (calendar years). The left vertical axis represents incidence rates for the age effect and the right vertical axis represents the relative risk for the cohort and period effect. The drift is added to the non-linear birth cohort effects and the right plot presents the period effect as residual ratio rates