Urban Food Deserts and Cardiovascular Health: Evaluating the Impact of Nutritional Inequities on Elderly Populations in Santiago

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The authors used a geographically weighted multi-scale regression to analyze the relationship among geographic location of new cardiovascular patients, voronoi distribution of new cardiovascular patients and food deserts in the Santiago metropolitan area. This is an interesting and bold research, and the effect of nutritional inequities on elderly population in Santiago can be given. With the development of urbanization of cities, the food structure, nutritional and health issues, food security, food circulation, and so on all have significant changes. The suggestions gave this study is useful to the sustainable food systems in the developed and developing countries.

Suggestions,

1)     Line 75- 79, although the authors cited the refs (13,14, and 15) on the concept of food desert. The authors had better introduce the new concept of food desert with more than twenty years of economic and social development.

2)     Geographically weighted multi-scale regression (MGWR) should be expressed in a fixed mode in the whole text.

3)     When the authors used the new patients data in the cardiovascular program, how many years data were used?

4)     The conclusion section is too long.

Author Response

Comments 1:  Line 75- 79, although the authors cited the refs (13,14, and 15) on the concept of food desert. The authors had better introduce the new concept of food desert with more than twenty years of economic and social development.

Response: Thank you for the comment. The paragraph was edited to add relevant information that highlights other considerations for the definition of food desert. Reference 15 was changed. See manuscript highlighted in red.

Comments 2: Geographically weighted multi-scale regression (MGWR) should be expressed in a fixed mode in the whole text. See manuscript highlighted in red.

Response: Thank you for the comments. The term Geographically weighted multi-scale regression (MGWR) has been modified and is consistent throughout the text.

Comments 3:  When the authors used the new patients data in the cardiovascular program, how many years data were used?

Response: Thank you for the comment. The year of new patients is only 2018. Selected as a year without the effects of the social uprising or pandemic.

Comments 4: The conclusion section is too long.

Response: Thanks for the comment. The conclusion has been edited and is shorter. See manuscript highlighted in red.

Reviewer 2 Report

Comments and Suggestions for Authors

As a reviewer for the article titled "Urban Food Deserts and Cardiovascular Health: Evaluating the Impact of Nutritional Inequities on Elderly Populations in Santiago," here are some comments and considerations that might be relevant:

•  
1. Title and Abstract

• 1.1. The title accurately reflects the content of the study, focusing on the relationship between food deserts and cardiovascular health among the elderly in Santiago.
• 1.2. The abstract provides a comprehensive overview of the study's objectives, methods, and key findings. It effectively highlights the significance of the research and its implications for public health policy.

•  

2. Introduction

• 2.1. The introduction sets the stage well by discussing the broader context of food security and nutritional transitions in Chile. It effectively outlines the problem of food deserts and their potential impact on health.
• 2.2. The literature review is thorough, providing a solid foundation for the study. However, it could benefit from a more detailed discussion of previous research specifically linking food deserts to cardiovascular health outcomes.

•  

3. Methodology

• 3.1. The use of geographically weighted multiscale regression (MGWR) is a strength of the study, allowing for the analysis of spatial heterogeneity in the data.
• 3.2. The choice of 2018 as the study year is well-justified, considering the socio-political context and data availability.
• 3.3. The methodology section is detailed, but it might be helpful to include more information on the limitations of the MGWR model and how they were addressed.

•  

4. Results

• 4.1. The results are clearly presented, with tables and figures that effectively illustrate the findings.
• 4.2. The significant improvement in model fit from the global regression to the MGWR model is well-documented, highlighting the importance of spatial analysis.
• 4.3. The discussion of local r² values and residuals provides valuable insights into the spatial variability of the relationship between food deserts and cardiovascular health.

•  

5. Discussion

• 5.1. The discussion effectively interprets the results in the context of existing literature and public health implications.
• 5.2. The study's emphasis on tailored public health interventions is well-argued, supported by the spatial heterogeneity observed in the results.
• 5.3. The discussion could be strengthened by considering additional factors that might influence cardiovascular health, such as physical activity and healthcare access.

•  

6. Conclusions

• 6.1. The conclusions are well-supported by the study's findings, emphasizing the need for integrated urban planning and public health strategies.
• 6.2. The call for further research into other health determinants and temporal dynamics is appropriate and highlights areas for future investigation.

•  

7. References

• 7.1. The references are comprehensive and relevant, covering a wide range of studies related to food environments, health outcomes, and spatial analysis.

Overall, this study makes a valuable contribution to understanding the impact of food deserts on cardiovascular health among the elderly in Santiago. It provides important insights for policymakers and urban planners aiming to address health disparities through improved food accessibility. Further exploration of additional health determinants and longitudinal data could enhance the robustness of the findings.

Here are some further recommendations for improving the article:

•  
1. Enhance Literature Review

• 1.1. Include more specific studies that directly link food deserts to cardiovascular health outcomes. This would strengthen the foundation of the research and provide a clearer context for the study's contributions.
• 1.2. Discuss potential mechanisms through which food deserts might influence cardiovascular health, such as dietary patterns and stress related to food insecurity.

•  

2. Clarify Methodological Details

• 2.1. Provide additional information on the limitations of the MGWR model, such as potential biases or assumptions, and how these were addressed in the study.
• 2.2. Consider including a brief explanation of the Voronoi diagram and its relevance to the study for readers who may not be familiar with this spatial analysis technique.

•  

3. Expand Discussion on Results

• 3.1. Explore the implications of the spatial variability in more detail, particularly how it might inform targeted interventions in specific neighbourhoods.
• 3.2. Discuss the potential role of other factors, such as healthcare access, physical activity, and social support, in influencing cardiovascular health outcomes.

•  

4. Address Data Limitations

• 4.1. Acknowledge any limitations related to the data used, such as the reliance on 2018 data and the potential impact of socio-political events on the findings.
• 4.2. Consider discussing the potential for data inaccuracies or gaps, particularly in the context of spatial and demographic information.

•  

5. Strengthen Policy Recommendations

• 5.1. Provide more specific policy recommendations based on the study's findings, such as strategies for improving food access in high-risk areas.
• 5.2. Discuss the potential for interdisciplinary approaches that integrate urban planning, public health, and community engagement to address food deserts.

•  

6. Future Research Directions

• 6.1. Suggest exploring temporal dynamics in future studies to understand how the relationship between food deserts and cardiovascular health evolves over time.
• 6.2. Recommend incorporating additional health determinants, such as lifestyle factors and social determinants, to provide a more comprehensive analysis of cardiovascular health outcomes.

Implementing these recommendations could enhance the clarity, depth, and impact of the study, providing more robust insights for both academic and policy audiences.

 

 

 

Comments for author File: Comments.pdf

Comments on the Quality of English Language

 

The article is generally well-written, with clear and precise language that effectively communicates the research findings and their implications. The use of technical terminology is appropriate for the academic audience, and the structure of the paper is logical and coherent. However, there are a few areas where improvements could be made:

• 1. Clarity and Conciseness
  • 1.1. Some sentences are complex and could be simplified to enhance readability. Consider breaking down longer sentences into shorter, more direct ones.
  • 1.2. Ensure that all technical terms and methodologies are clearly defined for readers who may not be familiar with them.
• 2. Consistency
  • 2.1. Maintain consistency in the use of terms throughout the article. For example, ensure that terms like "food deserts" and "cardiovascular health" are used consistently without unnecessary variation.
• 3. Grammar and Syntax
  • 3.1. Review the article for minor grammatical errors or awkward phrasing that could be improved. A thorough proofreading could help identify and correct these issues.
• 4. Use of Passive Voice
  • 4.1. While the passive voice is appropriate in some sections, consider using the active voice where possible to make the writing more engaging and direct.

 

Overall, the article demonstrates a strong command of the English language, but addressing these areas could further enhance its clarity and impact.

Author Response

Enhance Literature Review

Comments: Include more specific studies that directly link food deserts to cardiovascular health outcomes. This would strengthen the foundation of the research and provide a clearer context for the study's contributions.

Response: Thank you for the comment. The change has been made.

Comments: Discuss potential mechanisms through which food deserts might influence cardiovascular health, such as dietary patterns and stress related to food insecurity.

Response: Thank you for the comment. The change has been made.

 Clarify Methodological Details

Comments: Provide additional information on the limitations of the MGWR model, such as potential biases or assumptions, and how these were addressed in the study.

Response: Thank you for the comment. A further explanation was incorporated to the methods section.

Comments: Consider including a brief explanation of the Voronoi diagram and its relevance to the study for readers who may not be familiar with this spatial analysis technique.

Response: Thank you for the comment. The change has been made.

 Expand Discussion on Results

Comments: Explore the implications of the spatial variability in more detail, particularly how it might inform targeted interventions in specific neighbourhoods.

Response: Thank you for the comment. A further explanation was incorporated to the discussion and conclusion sections.

Comments: Discuss the potential role of other factors, such as healthcare access, physical activity, and social support, in influencing cardiovascular health outcomes.

Response: Thank you for the comment. The change has been made.

Address Data Limitations

Comments: Acknowledge any limitations related to the data used, such as the reliance on 2018 data and the potential impact of socio-political events on the findings.

Response Thank you for the comment. A more detailed explanation was incorporated in the methods section to clarify this point and some further reflections on the potential impact of these findings in the discussion section.

Comments: Consider discussing the potential for data inaccuracies or gaps, particularly in the context of spatial and demographic information.

Response Thank you for the suggestion. We acknowledged the limitations of the data in the methodology section.

 Strengthen Policy Recommendations

Comments: Provide more specific policy recommendations based on the study's findings, such as strategies for improving food access in high-risk areas.

Response: Thank you for the suggestion. As you will see, we elaborated a renewed conclusion section where we address this issue.  

Comments: Discuss the potential for interdisciplinary approaches that integrate urban planning, public health, and community engagement to address food deserts.

Response: Thank you for the idea. Following the previous response, this is now addressed in the conclusion section.  

 Future Research Directions

Comments: Suggest exploring temporal dynamics in future studies to understand how the relationship between food deserts and cardiovascular health evolves over time.

Response: Thank you for the idea. This was incorporated in the discussion section.

Comments: Recommend incorporating additional health determinants, such as lifestyle factors and social determinants, to provide a more comprehensive analysis of cardiovascular health outcomes.

Response: Thank you for the idea, we addressed this suggestion but we do not do this because it implies a methodological change and a different type of research and calculations.

Implementing these recommendations could enhance the clarity, depth, and impact of the study, providing more robust insights for both academic and policy audiences.

Comments on the Quality of English Language

The article is generally well-written, with clear and precise language that effectively communicates the research findings and their implications. The use of technical terminology is appropriate for the academic audience, and the structure of the paper is logical and coherent. However, there are a few areas where improvements could be made:

Clarity and Conciseness

Comments: Some sentences are complex and could be simplified to enhance readability. Consider breaking down longer sentences into shorter, more direct ones.

Response: We performed a throughout revision and changes in this matter were made.

Comments: Ensure that all technical terms and methodologies are clearly defined for readers who may not be familiar with them.

Response: Thanks for this observation, changes were introduced to ensure clarity of terms.

Consistency

Comments: Maintain consistency in the use of terms throughout the article. For example, ensure that terms like "food deserts" and "cardiovascular health" are used consistently without unnecessary variation.

Response: Thank you for the comment. The change has been made.

Grammar and Syntax

Comments: Review the article for minor grammatical errors or awkward phrasing that could be improved. A thorough proofreading could help identify and correct these issues.

Response: Thank you for the comment. The proofreading was approved identifying some mistakes already addressed.

Comments: While the passive voice is appropriate in some sections, consider using the active voice where possible to make the writing more engaging and direct.

Response : Thank you for the comment. The proofreading was approved identifying some mistakes already addressed.

 Overall, the article demonstrates a strong command of the English language.

Thanks.

Reviewer 3 Report

Comments and Suggestions for Authors

The authors have submitted the entitled manuscript "Urban Food Deserts and Cardiovascular Health: Evaluating the Impact of Nutritional Inequities on Elderly Populations in Santiago" which aimed to examine the link between food deserts and cardiovascular disease among older adults in Santiago's Metropolitan Region, Chile.

Please consider using Grammarly or a similar platform to check for errors in grammar throughout.

The overall study methodology and outline of the manuscript makes logical sense and is sound. the methods used make sense and is an interesting analysis used to identify the regions that are associated with poor health and food deserts. The main concerns of this current manuscript are listed below within the specific sections. Largely, there are areas in need of clarification.

Methods:

In the method the inclusion criteria is stated that individuals over the age of 15 were included? Is this true, as I thought it said that the age was 65? Please clarify.

-This sentence "Specifically, the monthly statistical summaries for the year 2018 are elaborated from the new admissions to the system, in the "Series A" of the public data set, contemplating only admissions to the cardiovascular health program for persons over 60 years of age, for each health facility indexed in this database" has quite a bit going on. Is there a way to break this up or simply the explanation? Perhaps stating this as "The data were obtained from the 2018 Chilean Ministry of Health "Series A" monthly statistical summaries of the statistics department, wherein only persons over the age of 60 were indexed." Would this convey the same message here? the original two opening sentences are a bit wordy and hard to digest.

-Some part of the methods need to be reworded to past tense. The document should be in past tense. Please double check this.

-Please state that this was a retrospective study design in the methods section. Preferably in the opening paragraph.

-In the methods section, please include a statement of study approval (IRB statement).

-Can figure 2 be clarified on what the influential factors are distinguished by the colors?

-Please consider rewording this statement "the Voronoi layer is loaded with information" as this is very colloquial

Results:

-Tables: perhaps fit the tables without the added spacing (or widened cells). For instance, in tables 1 and 2, the variable column has very wide cells that can be shortened to best fit the terms.

-Please include definitions for the abbreviations in the table legends (for example, table 2, ENP_j.. please define this in legend of table).

Discussion:

-There are not citations provided in the discussion. It is hard to compare and contrast with other work here, and this is critical to but the present study findings into context. Please provide citations within the discussion.

-in the opening discussion paragraph, the authors mention "traditional" diets (page 11, line 372). Please clarify what this means. Is this traditional to the culture? Is this, for example, paleo (i.e., following those recommendations that mirror our ancestors' dietary patterns)? This clarification would aid the understanding of the statement.

-Please cite the previous work for the following statement "The findings support previous research suggesting that areas with limited access to healthy foods contribute to poorer dietary quality and increased risk of chronic diseases.".

-Please expand on this "Conversely, areas with lower r2 values, such as central and northern Santiago, may have better access to healthy foods but still  exhibit some degree of health inequities." If there is access (i.e., not a food desert) then why the issue? Is there previous work that this aligns with? How so? If not, why not? Please provide a contrast or compare to other work here to better expand why there is still this inequity. Perhaps it is another type of factor... Maybe (and not that your study showed this) there is an individual factor (motivation, lack of time, lack of knowledge) that other studies with a similar note on location and disparities has found.

-The following likely can be expanded on "The study's results suggest that enhancing this program with targeted interventions to improve food access in high-risk areas could further reduce cardiovascular disease prevalence. This approach aligns with the programme’s goals of preventing morbidity and premature mortality while improving life quality." Is there any data/literature, that suggest a plan of action? It does make sense... if you have an an intervention to boost access then there will likely be less food-desert-related issues (however, with the other note that those who have access had similar relationships [above comment on the central and northern Santiago] this might create an interesting issues... being is it that once access is granted... is there something more to this that ultimately related (more strongly) to the CVD outcomes?). In other words, can the authors speculate (unless there are data to support their ideas here) on what specific interventions will be needed. This is a critical point of discussion here.

-Are there data available on socioeconomic status? If so, can these be included within the analysis? This seems to be an important piece that could help to explain the issues discussed on food deserts? Does the database used house this data?

-When saying "The use of MGWR allows for a nuanced understanding of how these relationships vary across different neighborhoods" to my understanding, the one relationship identified was how overall cardiovascular health relates to the area... what other relationships were identified? Perhaps this is a misunderstanding in the wording here. Please clarify.

-Also, "Understanding how these relationships evolve over time can provide deeper insights into the long-term impacts of food environments on health" Can the authors clarify this statement as well, specifically what it is meant by evolving over time... ? This was not an outcome of the present study. Does this mean to suggest that assessing this over time would be advantageous?

-The mention of including things like "physical activity, healthcare access, and social support networks" in the analysis to add more detail is great, but why was this not included in the present study? Is this a limitation of the dataset? Please clarify.

Author Response

Comment 1: In the method the inclusion criteria is stated that individuals over the age of 15 were included? Is this true, as I thought it said that the age was 65? Please clarify.

Response 1: Thank you for your comment. We have added clarification on line 144 that the data analyzed corresponds to individuals over 60 years of age. See the manuscript, highlighted in red: "However, for the purposes of this study, only individuals over 60 years of age were considered." This clarification also appears in the Methods section on lines 127 and 128.

Comment 2: This sentence "Specifically, the monthly statistical summaries for the year 2018 are elaborated from the new admissions to the system, in the "Series A" of the public data set, contemplating only admissions to the cardiovascular health program for persons over 60 years of age, for each health facility indexed in this database" has quite a bit going on. Is there a way to break this up or simply the explanation? Perhaps stating this as "The data were obtained from the 2018 Chilean Ministry of Health "Series A" monthly statistical summaries of the statistics department, wherein only persons over the age of 60 were indexed." Would this convey the same message here? the original two opening sentences are a bit wordy and hard to digest.

Response 2: Thank you for the comment. The change has been made.

Comment 3: Some part of the methods need to be reworded to past tense. The document should be in past tense. Please double check this.

Response 3: Thank you for the comment. The change has been made.

Comment 4: Please state that this was a retrospective study design in the methods section. Preferably in the opening paragraph.

Response 4: Thank you for the comment. The change has been made.

Comment 5: In the methods section, please include a statement of study approval (IRB statement).

Response 5: Thank you for the comment. The change has been made.

Comment 6: Can figure 2 be clarified on what the influential factors are distinguished by the colors?

Response 6: Thanks for the observation. Each shape resulting from the Voronoi transformation summarizes the number of new patients admitted to the Ministry of Health's cardiovascular program in the year 2018, which in figure 2 is expressed in the symbology at the bottom left. We have added a text that clarifies this issue in the text.

Comment 7: Please consider rewording this statement "the Voronoi layer is loaded with information" as this is very colloquial.

Response 7: Thank you for the comment. The change has been made.

Comment 8: Tables: perhaps fit the tables without the added spacing (or widened cells). For instance, in tables 1 and 2, the variable column has very wide cells that can be shortened to best fit the terms.

Response 8: Thank you for the comment. The change has been made.

Comment 9: Please include definitions for the abbreviations in the table legends (for example, table 2, ENP_j.. please define this in legend of table).

Response 9: Thank you for the observation. The change has been made.

Comment 10: There are not citations provided in the discussion. It is hard to compare and contrast with other work here, and this is critical to but the present study findings into context. Please provide citations within the discussion.

Response 10: Thank you for the comment. The change has been made, and the citation has been added.

Comment 11: in the opening discussion paragraph, the authors mention "traditional" diets (page 11, line 372). Please clarify what this means. Is this traditional to the culture? Is this, for example, paleo (i.e., following those recommendations that mirror our ancestors' dietary patterns)? This clarification would aid the understanding of the statement.

Response 11: Thank you for the comment. The sentence has been clarified by indicating the characteristics of the traditional diet and the nutritional transition period mentioned earlier. A new citation has also been provided.

Comment 12: Please cite the previous work for the following statement "The findings support previous research suggesting that areas with limited access to healthy foods contribute to poorer dietary quality and increased risk of chronic diseases."

Response 12: Thank you for the comment. Citations supporting the statement have been added.

Comment 13: Please expand on this "Conversely, areas with lower r2 values, such as central and northern Santiago, may have better access to healthy foods but still exhibit some degree of health inequities." If there is access (i.e., not a food desert) then why the issue? Is there previous work that this aligns with? How so? If not, why not? Please provide a contrast or compare to other work here to better expand why there is still this inequity. Perhaps it is another type of factor... Maybe (and not that your study showed this) there is an individual factor (motivation, lack of time, lack of knowledge) that other studies with a similar note on location and disparities has found.

Response 13: Thank you for your observation. This is correct, as we are not testing other health inequities that may arise from this factor. We have adjusted the phrasing to avoid any potential misleading implications from our findings.

Comment 14: following likely can be expanded on "The study's results suggest that enhancing this program with targeted interventions to improve food access in high-risk areas could further reduce cardiovascular disease prevalence. This approach aligns with the programme’s goals of preventing morbidity and premature mortality while improving life quality." Is there any data/literature, that suggest a plan of action? It does make sense... if you have an an intervention to boost access then there will likely be less food-desert-related issues (however, with the other note that those who have access had similar relationships [above comment on the central and northern Santiago] this might create an interesting issues... being is it that once access is granted... is there something more to this that ultimately related (more strongly) to the CVD outcomes?). In other words, can the authors speculate (unless there are data to support their ideas here) on what specific interventions will be needed. This is a critical point of discussion here.

Response 14: The study suggests that targeted interventions to improve food access in high-risk areas could reduce the prevalence of cardiovascular disease (CVD) among the elderly in Santiago. However, the complexity increases when considering areas like central and northern Santiago, where even with better food access, the relationship with CVD outcomes remains weak. Based on our study, we speculate that while food access is vital, it may need to be part of a more comprehensive intervention strategy that also addresses other determinants like healthcare access, education, and socioeconomic conditions. This is where nutritional studies meet urban planning. In light of this, we propose that interventions in high-risk areas should not only focus on improving food access but also consider a holistic approach. This could include improving healthcare infrastructure, offering educational programs on nutrition, and addressing economic barriers to healthy eating. Furthermore, longitudinal studies are suggested to track the long-term effects of such multifaceted interventions on CVD outcomes, providing more robust evidence to support these speculations. We have not yet performed this type of study but will add it to the discussion as part of further research ideas.

Comment 15: Are there data available on socioeconomic status? If so, can these be included within the analysis? This seems to be an important piece that could help to explain the issues discussed on food deserts? Does the database used house this data?

Response 15: We understand the suggestion; however, this would require recalculating all the indices and redoing the study, as the available socioeconomic weightings would entail changes in the factors. It would be a different research. Additionally, the methodological design would likely need to be adjusted to accommodate an expansion of the variables under study, which would essentially mean altering the results, discussions, and conclusions.

Comment 16: When saying "The use of MGWR allows for a nuanced understanding of how these relationships vary across different neighborhoods" to my understanding, the one relationship identified was how overall cardiovascular health relates to the area... what other relationships were identified? Perhaps this is a misunderstanding in the wording here. Please clarify.

Response 16: Yes, this is a mistake; it should be "relationship" and not "relationships." The change has been made.

Comment 17: Also, "Understanding how these relationships evolve over time can provide deeper insights into the long-term impacts of food environments on health" Can the authors clarify this statement as well, specifically what it is meant by evolving over time... ? This was not an outcome of the present study. Does this mean to suggest that assessing this over time would be advantageous?

Response 17: Thank you for the comment. The statement "Understanding how these relationships evolve over time can provide deeper insights into the long-term impacts of food environments on health" was meant to suggest that assessing the evolution of food environments and their impact on health over time would be advantageous. While this was not an outcome of the present study, we believe that longitudinal studies could provide valuable insights into how changes in food environments, such as the transition from food deserts to food oases, influence health outcomes over the long term. To clarify this, we will revise the text to better reflect this intent.

Comment 18: The mention of including things like "physical activity, healthcare access, and social support networks" in the analysis to add more detail is great, but why was this not included in the present study? Is this a limitation of the dataset? Please clarify.

Response 18: Yes, this is a limitation of the dataset, as information at the block scale for this type of study is scarce in Chile. Furthermore, producing this information would be fundamental for conducting other types of analysis, as mentioned above. We have clarified this in the text to avoid any confusion.