Lancet Planetary Health最新文献

Background

Ambient air pollution, including particulate matter (such as PM₁₀ and PM_2·5) and nitrogen dioxide (NO₂), has been linked to increases in mortality. Whether populations’ vulnerability to these pollutants has changed over time is unclear, and studies on this topic do not include multicountry analysis. We evaluated whether changes in exposure to air pollutants were associated with changes in mortality effect estimates over time.

Methods

We extracted cause-specific mortality and air pollution data collected between 1995 and 2016 from the Multi-Country Multi-City (MCC) Collaborative Research Network database. We applied a two-stage approach to analyse the short-term effects of NO₂, PM₁₀, and PM_2·5 on cause-specific mortality using city-specific time series regression analyses and multilevel random-effects meta-analysis. We assessed changes over time using a longitudinal meta-regression with time as a linear fixed term and explored potential sources of heterogeneity and two-pollutant models.

Findings

Over 21·6 million cardiovascular and 7·7 million respiratory deaths in 380 cities across 24 countries over the study period were included in the analysis. All three air pollutants showed decreasing concentrations over time. The pooled results suggested no significant temporal change in the effect estimates per unit exposure of PM₁₀, PM_2·5, or NO₂ and mortality. However, the risk of cardiovascular mortality increased from 0·37% (95% CI –0·05 to 0·80) in 1998 to 0·85% (0·55 to 1·16) in 2012 with a 10 μg/m³ increase in PM_2·5. Two-pollutant models generally showed similar results to single-pollutant models for PM fractions and indicated temporal differences for NO₂.

Interpretation

Although air pollution levels decreased during the study period, the effect sizes per unit increase in air pollution concentration have not changed. This observation might be due to the composition, toxicity, and sources of air pollution, as well as other factors, such as socioeconomic determinants or changes in population distribution and susceptibility.

Funding

None.

Work to reduce environmental pollution from the health system is hampered by an absence of consensus on the definition of environmentally sustainable health care and the relevant measurement needed. This scoping review aims to encourage standardisation across sustainability efforts by examining how environmentally sustainable health care is defined and measured in current literature. We conducted a scoping review to identify candidate publications that included either a definition or description of environmentally sustainable health care or a measurement of the impact of health care on the environment. 328 publications were included in the final analysis. 52 publications included definitions or descriptions of environmentally sustainable health care. Results of the study highlight the heterogeneity in the current definition, measurement, and measurement calculation methods of environmentally sustainable health care in published literature. Work is needed to create more harmonised definitions and measurement to support progress and reduce environmental pollution from health care.

Metrics for health-care sustainability are crucial for tracking progress and understanding the advantages of different operations or systems as the health-care sector addresses the climate crisis and other environmental challenges. Measurement of the key metrics of absolute energy use and greenhouse gas emissions now has substantial momentum, but our overall measurement framework generally has serious deficiencies. Because existing metrics are often borrowed from other sectors, many are unconnected to the specifics of health-care provision or existing health system performance indicators, the potential negative effects of health care on public health are largely absent, a consistent and standardised set of health-care sustainability measurement concepts does not yet exist, and current dynamics in health systems such as privatisation are largely ignored. The next generation of health-care sustainability metrics must address these deficiencies by expanding the scope of observation and the entry points for interventions. Specifically, metrics should be standardised, reliable, meaningful, integrated with data management systems, fair, and aligned with the core mission of health care. Incentives with the potential to contradict sustainability goals must be addressed in future planning and implementation if the next generation of metrics is to be effective and incentivise positive systemic change.

Background

Plant-based diets (PBDs) and planetary-health diets (PHDs) are recommended for their potential health and environmental benefits, but population-based evidence in diverse cultures is scarce.

Methods

We included 9364 adults aged 45 years and older (52·3% female, 47·7% male) from the open cohort of the China Health and Nutrition Survey. Dietary intake was assessed using 3-day 24 h dietary recalls combined with weighing methods from 1997 to 2011, and mortality was documented from 1997 to 2015. We calculated the overall PBD index (PDI), healthful PBD index (hPDI), and unhealthful PBD index (uPDI; ranges 18–90), and the PHD score (range 0–140). We also estimated the related greenhouse gas emissions, land appropriation, and total water footprint and examined their associations with mortality.

Findings

PBD indices were inversely related to greenhouse gas emissions, land appropriation, and total water footprint, whereas higher PHD score was related to higher environmental burdens (p<0·0001). During follow-up (mean 9·2 years), 792 (8·5%) death cases were documented. PDI (HR 1·08 [95% CI 0·88–1·32]) and hPDI (0·98 [0·80–1·21]) were not significantly associated with mortality, whereas higher uPDI was related to a higher mortality risk (1·55 [1·26–1·91]). In contrast, higher PHD score was associated with lower mortality risk (0·79 [0·63–0·99]).

Interpretation

The PBDs showed environmental benefits, but are not necessarily associated with lower mortality risk. The PHD, developed mainly in western populations, was related to lower mortality risk but higher environmental burdens in the Chinese population.

Funding

Fundamental Research Funds for the Central Universities, Zhejiang University Global Partnership Fund, and National Natural Science Foundation of China.