Low Back Pain Incidence Trends Globally, Regionally, and Nationally, 1990-2019: An Age-Period-Cohort Analysis, Cross-Sectional Studies.

Introduction: Low back pain (LBP) imposes a significant burden on global health, yet it remains deficient in comprehensive investigations pertaining to its incidence patterns. The aim of this study was to analyse global, regional and national trends and associated factors in the incidence of LBP from 1990-2019.

Methods: In order to examine global and country-specific 30-year incidence patterns of LBP, data were obtained from the 2019 Global Burden of Disease Study. An age-period cohort (APC) model was utilised to determine annual percent changes, age-specific changes, and period/cohort effects.

Results: The age-standardized global LBP incidence rate significantly declined from 1990-2019. However, the absolute number of cases increased by 2.39 billion, predominantly in middle-, low-middle- and low-socio-demographic index (SDI) regions, affecting mostly 50-69 years old with a higher incidence in women. LBP incidence increased progressively from low to high SDI regions. Period and cohort effects trended downward in all regions except high-SDI countries, which had the lowest incidence decline and a slight rebound after 2012.

Conclusions: Our study updates global and regional LBP incidence from 1990-2019 using APC modelling, showing declining age-standardized rates globally but increased case numbers due to population growth and ageing. Prevention likely helped reduce incidence, but more health strengthening and minimally invasive treatments are still needed, especially where LBP has plateaued or rebounded recently.