Nelson Alexandre Rodrigues Tavares Riboflavin status and effects of supplementation on ...

156 Pages·2009·0.6 MB·English

Nelson Alexandre Rodrigues Tavares

Riboflavin status and effects of supplementation on biomarkers of cardiovascular
disease in the elderly

Academic Dissertation

Porto, 2009

Nelson Tavares

Academic Dissertation for the ‘’Doutoramento em Ciências da Nutrição’’ to be presented,
with the permission of the Faculty of Nutrition and Food Sciences, University of Porto,
Portugal, for public examination.

Supervised by:
Professor Pedro Alexandre Afonso de Sousa Moreira
Faculty of Nutrition and Food Sciences,
University of Porto
Portugal

Professor Teresa Maria de Serpa Pinto Freitas do Amaral
Faculty of Nutrition and Food Sciences,
University of Porto
Portugal
Aos meus pais
À Laura, Inês e Adriana
Nelson Tavares

Acknowledgements

I would like to thank Profs. Pedro Moreira and Teresa Amaral, who have been
my supervisors for this project. Thanks to Pedro and Teresa for all their help
throughout the project. Elvira Lopes has been extremely helpful with
questionnaires, I am grateful for your time.
I would also like to thank Drs. Joaquim Espirito Santo, Elisabete João, Cândida
Carvalho, Conceição Silva, Odete Ribeiro and Rosa Lima from the different day
social care centers who allowed me to recruit elderly people.
A special thanks to Bayer, Roche, Dade Behring, for reagents used on
biochemical measurements, Normax for blood collecting material. Dr. Ferreira
de Almeida has been extremely helpful in the J.P.Barros Laboratory as has Dr.
Isabel Baldaia in LabMED Porto. Dr. Elizabeth Malheiro from Lecifarma who
supplies the supplement and placebo. Prof. Carla Lopes who makes possible
the conversion of questionnaires.
I would like to thank Dr. Lucinda Tavares da Silva for making it possible for me
to have some time to go to Porto when necessary, and to prepare the
dissertation.
I owe a special thanks to my daughters Laura and Inês and my beloved wife
Adriana. Without their support the completion of this dissertation would not have
been possible.
Finally, I’d like to say a big thank-you to all elderly people that participate in the
intervention, allowed us to take their blood on two occasions. I hope they
enjoyed learning something about their riboflavin status.

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This doctoral thesis is based on the following papers:

I. Tavares N. Putative role of riboflavin in disease prevention. Arquivos de
Medicina 2005; 19: 55-66.

II. Tavares N, Moreira P, Amaral T. EGRAC, serum folate and its dietary
correlates estimated from semi quantitative food-frequency questionnaire in
elderly. Submitted.

III. Tavares NR, Moreira PA, Amaral TF. Riboflavin supplementation and
biomarkers of cardiovascular disease in elderly. J Nutr Health Aging 2009;
13:441-6.

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Contents
Page
1.Introduction.................................................................…......................7

2. Putative role of riboflavin in disease prevention ……………………..40

3. Riboflavin, serum folate and its dietary correlates estimated from
semi quantitative food frequency questionnaire in elderly.....................83

4. Riboflavin supplementation and biomarkers of
cardiovascular disease in the elderly..................................................109

5. Conclusions and future perspectives..............................................140

6. Abstract...........................................................................................144

7. Resumo...........................................................................................148

8. Resumé.........................................................................…..............152

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1. Introduction

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In this introduction the state of the art knowledge concerning the impact of age-
related nutrition issues promoting health and reducing the risk of the most
common elderly diseases, particularly cardiovascular diseases, will be
reviewed.
In the developed world, cardiovascular diseases are the predominant cause of
disability and death in elderly people(1). Some nutritional causes are implied in
the cardiovascular diseases, one of which is a low B vitamin intakes(2).
Evidence exists that low B vitamin intakes and high homocysteine
concentrations are common problems among older adults in the United
States(3).
The importance of riboflavin is less clear; however, act as cofactor in the
enzymatic breakdown of homocysteine and supplementation might play a role in
ensuring maximal reductions in homocysteine levels(4).
Portuguese people have one of the lowest levels of life expectancy in the Eur-A,
the reference group as designated by World Health Organization, which
includes 27 european countries, despite a gain of 4.5 years over the past 20
years. In Portugal, girls born in 2002 can expect to live almost 81 years and
boys slightly less than 74 years, which is 1.5 and 2.0 years less than their Eur-A
counterparts, respectively (5). Although we currently are seeing the results of the
baby boom, the Portuguese population aged 65 years and older is expected to
grow from about 17% of the population in 2003 to projected 23% in 2030 (5). In
addition, World Health Organization estimates that, on average, Portuguese
people can expect to be healthy for about 90% of their lives. They lose on
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average 7.8 years to illness – the difference between life expectancy and
healthy life expectancy (6).
Due to medical treatment advances, it is reasonable to expect the average life
span to reach or exceed 100 years in the 21st century (7). However, because the
average age at chronic disease onset has not risen to the same extent as life
expectancy, an elderly currently aged 75 years can look forward to only 4 more
years of active health followed by more than 7 years of disability. If the age of
chronic disease onset does not increase commensurate to the added years of
life still to come, a growing number of centenarians will spend the last 2
decades of their lives living with the serious and debilitating consequences of
chronic disease. This is not a future that anyone is happy to contemplate (8).

Over the recent decades the health status of the Portuguese population has
improved (5). This can be explained both to more significant progress in 30% of
the municipalities and to the diminishing disparities among regions between
1991 and 2001. Both effects are related to social and health factors and
behaviours. However, there is still some concern over regional disparities,
particularly between urban-coastal and rural-interior regions. The latter had, and
still have, the worst health condition. Rural regions are also the poorest in the
country. Health inequalities are associated with economic and social factors,
such as income, living conditions, unemployment, health care and illiteracy (9).
The exact relation between literacy and health is still unclear, being recognized
that people with low literacy are more likely to report having poor health, and are
more likely to have diabetes and heart failure, than those with adequate
literacy(10).
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