In this study, we systematically and synthetically illustrated the global burden of GC associated with high sodium intake across different genders, ages, and regions, and its temporal and spatial trends in 204 countries and territories from 1990 to 2019. Our findings indicated the ASMR and ASDR attributable to high sodium intake had decreased by approximately 60% in 2019 compared to 1990. Over the past three decades, males and the elderly have consistently suffered from a higher disease burden than females and younger age groups. The impact of high sodium intake on GC is particularly evident in East Asia and high-income Asia Pacific countries with middle and high-middle SDI. Furthermore, the projections indicated that the global burden of GC attributable to high sodium intake will continue to decrease over the next 31 years.
Globally, the burden of GC caused by high sodium intake has exhibited a decreasing trend between 1990 and 2019, aligning with the findings of Chen X et al [21]. This downtrend can be attributed to two primary factors. Firstly, a growing awareness of the health risks caused by high sodium intake has lead individuals to adopt lower-sodium diets and eat less preserved foods. Secondly, the implementation of salt reduction measures has had a significant impact on reducing the global disease burden. In 2006, the WHO proposed that interventions to reduce salt consumption in the whole population are highly cost-effective and suggested that salt reduction strategies and interventions should be formulated according to each country's own situation [22]. In 2021, the WHO released a new set of global sodium benchmarks, aiming to achieve a 30% reduction in global sodium intake by encouraging industry to reduce sodium content in processed foods accordingly [23]. Many countries have responded to the call of the WHO, initiated national salt reduction actions, and formulated corresponding salt reduction guidelines [24–26].
The disease burden of GC caused by high sodium intake varies across different genders and different age groups. For different genders, the burden of the disease is approximately twice as high in males compared to females. This discrepancy is primarily attributed to estrogen [27–28]. Research has shown that the trefoil factor (TTF) protein offers protection and repair to damaged gastric mucosal epithelial cells, and estrogen can indirectly increase TTF protein expression by stimulating TTF gene expression [29]. Furthermore, in vitro experiments have observed that estrogen increases apoptosis in human GC cells [30]. For different age groups, the mortality and DALY rates related to GC caused by high sodium intake in the elderly are higher than in young people. This trend is particularly evident among those over the age of 60, where the disease burden is even higher. This is primarily attributed to demographic changes. With the deepening of global population aging, the number of elderly people is increasing rapidly [15], which increases the burden of GC caused by high sodium intake in the elderly. In addition, due to their lower immune function and resistance [31, 32], older adults are more susceptible to GC.
The burden of GC due to high sodium intake varied significantly across nations and regions between 1990 and 2019. This is consistent with the results of other studies of GC-related epidemiological trends [4]. East Asia emerged as the region with the heaviest disease burden, with Mongolia, China, and Korea as the principal contributors. This high burden in these countries may be attributed to their large population base, aging populace, and prevalent high-sodium dietary habits [20]. The advancement of economic levels and the enhancement of medical and health conditions in distinct regions also influenced the burden of GC caused by high sodium intake. As our results indicate, the burden of GC attributable to high sodium intake declined most rapidly in regions with high SDI. This trend is closely linked to the complete medical and health systems, as well as the broad coverage of health services in these areas, which have a high development index [33].
Our prediction results indicate a decline in the global burden of GC caused by high sodium intake, both in terms of ASMR and ASDR, over the next 31 years. This suggests that the implementation of salt reduction measures and the improvement of health care services have had a lasting positive impact. For instance, in Korea, Japan and China, sodium consumption has decreased significantly following the implementation of salt reduction policies [34–36]. However, it’s important to note that the sodium intake still exceeds the World Health Organization’s recommended limit of less than 5 grams per day. Therefore, it's crucial to continue promoting salt reduction awareness and modifying salt control interventions to ensure effective implementation of salt reduction actions. This will ultimately reduce the overall socioeconomic and health burden caused by GC attributed to high sodium intake.
Our study also exists some limitations. Firstly, the GBD 2019 data on the burden of gastric cancer caused by high sodium intake relies on just 21 sources from six countries, most of the outcome data were modeled according to the GBD methods [16]. Furthermore, the quality of available data varies across countries and regions [37]. This inevitably leads to a substantial deviation in the ascertainment of GC death in GBD studies. Second, the GBD study used 24-hour urinary sodium to assess sodium intake [15]. This single baseline measurement of 24-hour urinary sodium intake does not take daily changes in sodium intake and excretion into account, thereby affecting the accuracy of the estimates.