Journal of the American College of Nutrition
ISSN: 0731-5724 (Print) 1541-1087 (Online) Journal homepage: http://www.tandfonline.com/loi/uacn20
Sleep Quality in the Survival of Elderly Taiwanese: Roles for Dietary Diversity and Pyridoxine in Men and Women Yi-Chen Huang MPH , Mark L. Wahlqvist MD & Meei-Shyuan Lee DrPH To cite this article: Yi-Chen Huang MPH , Mark L. Wahlqvist MD & Meei-Shyuan Lee DrPH (2013) Sleep Quality in the Survival of Elderly Taiwanese: Roles for Dietary Diversity and Pyridoxine in Men and Women, Journal of the American College of Nutrition, 32:6, 417-427, DOI: 10.1080/07315724.2013.848158 To link to this article: http://dx.doi.org/10.1080/07315724.2013.848158
Published online: 10 Dec 2013.
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Full Terms & Conditions of access and use can be found at http://www.tandfonline.com/action/journalInformation?journalCode=uacn20 Download by: [Inter-American Development Bank (KNL/FHL)]
Date: 05 November 2015, At: 19:26
Sleep Quality in the Survival of Elderly Taiwanese: Roles for Dietary Diversity and Pyridoxine in Men and Women
Downloaded by [Inter-American Development Bank (KNL/FHL)] at 19:26 05 November 2015
Yi-Chen Huang, MPH, Mark L. Wahlqvist, MD, Meei-Shyuan Lee, DrPH Graduate Institute of Life Sciences, National Defense Medical Center, Taipei (Y.-C.H., M.-S.L.), Institute of Population Health Sciences, National Health Research Institutes, Taiwan, REPUBLIC OF CHINA (M.L.W.), Department of Epidemiology and Preventive Medicine and the Monash Asia Institute, Monash University, Melbourne, AUSTRALIA (M.L.W.), School of Public Health, National Defense Medical Center, Taiwan, REPUBLIC OF CHINA (M.L.W., M.-S.L.), Monash Asia Institute, Monash University, Caulfield East, Victoria, AUSTRALIA (M.L.W., M.-S.L.) Key words: vitamin B-6, DDS, sleep, gender, mortality Objectives: The purpose of this study was to investigate dietary contributors to relationships between sleep and all-cause mortality among elderly men and women using a prospective cohort study. Setting: The representative Nutrition and Health Survey in Taiwan (NAHSIT) for elders during 1999–2000. Subjects: One thousand eight hundred sixty-five individuals aged ≥65 years from NAHSIT (942 men and 923 women). Measures of Outcome: Dietary diversity scores (DDS) were from 24-hour dietary recalls. Participants were examined and fasting blood was taken. Sleep quality was assessed by questionnaire and classified as poor, fair, or good. Death registry linkage was made until December 31, 2008. Results: For women, poor sleepers had significantly lower vegetable and vitamin B-6 intakes compared to good sleepers (p < 0.05). For men, good and fair sleepers had a lower risk of death compared to poor sleepers after adjustment with hazards ratios (HRs) and 95% confidence intervals (CIs) of 0.60 (0.42–0.87) and 0.55 (0.36–0.86). The joint HRs for “DDS > 4 and good sleep” were 0.38 (0.22–0.66) for men and 0.52 (0.30–0.88) for women compared to “DDS ≤ 4 and poor sleep.” The joint HRs for “plasma pyridoxal phosphate (PLP) adequate and fair sleep” were 0.27 (0.11–0.65) and 0.49 (0.23–1.07) compared to “insufficient and poor sleep” for men and women; for women, PLP adequacy provided significantly reduced HRs for good and poor sleep. Conclusions: Sleep quality played a more important role in mortality for men than for women. Sufficient dietary diversity in men could offset the adverse effect on mortality of poor sleep. In women, PLP predicts mortality more than sleep does.
INTRODUCTION
munities have reported at least one chronic sleep complaint [5], which may have been quantitative or qualitative. Sleep quality is related to sociodemographic variables such as education and marital status; to health-related behaviors such as work hours, smoking, and alcohol consumption; to physical (obesity and related disorders) and mental (depression) health [6,7]; and to physical performance [8]. In addition, some studies have shown that women have more sleep problems than men [9–11]. Both short and long sleep durations are associated with increased morbidity and mortality [12–14], including obesity [15], diabetes [16], metabolic syndrome [17], cardiovascular disease
Sleep, diet, and nutrition rank highly in populist health culture, with as many as 182 million listings on the Google Internet search engine in 2011. However, this is not matched by the scientific literature, for which there are few studies. Those studies that are available have principally to do with the effect of sleep deprivation on energy expenditure [1] and intake [2,3] and their consequences for obesity [4]. Yet quality and quantity of life are dependent on sleep, and this becomes a particular problem with age. Over one half of the elderly in U.S. com-
Address correspondence to: Professor Meei-Shyuan Lee, School of Public Health, National Defense Medical Center, 161 Minchuan East Road, Sec. 6, Taipei, Taiwan 114, REPUBLIC OF CHINA. E-mail: [email protected] National Health Research Institutes, the funder of the study, had no role in the study design, data collection, data analysis, data interpretation, or writing of the report. All authors had access to the data and agreed to submit for publication. Abbreviations: ANOVA = analysis of variance, BMI = body mass index, CI = confidence intervals, DDS = dietary diversity score, EGRAC = glutathione reductase, ETKAC = erythrocyte transketolase, FFQ = food frequency questionnaire, HR = hazard ratio, METs = metabolic equivalents, NAHSIT = Nutrition and Health Survey in Taiwan, PLP = plasma pyridoxal phosphate, SF-36 = International Quality of Life Assessment 36-item Short Form.
Journal of the American College of Nutrition, Vol. 32, No. 6, 417–427 (2013) C American College of Nutrition Published by Taylor & Francis Group, LLC 417
Downloaded by [Inter-American Development Bank (KNL/FHL)] at 19:26 05 November 2015
Sleep, Dietary Quality, and Survival in Elders [18,19], and coronary heart disease [20]. Short sleep duration decreases leptin and increases ghrelin with increases in appetite [21] and food intake [2,3] and reduction in energy expenditure [1]. Taiwanese adolescents who have adequate sleep have a higher frequency of health-promoting behaviors such as a healthy diet, appreciation for life, responsibility for health, and exercise [22]. Intervention focusing on education on healthy dietary practices in elderly people has been associated with a modest increase in sleep duration and more stable indices of health [23]. There are few studies that have explored gender differences and diet quality in regard to sleep and mortality. We have studied these relationships and considered whether gender and diet-associated sleep patterns predict survival during a 10-year follow-up of an elderly Taiwanese population.
8. Have you used sleeping pills at all in the past 3 months? 9. How would you rate your overall sleep quality in the past 3 months?
The present study used the ninth question about overall sleep quality to categorize the sleep status of subjects as poor, fair, or good, because it was highly correlated with each of the other 8 questions (Table 1). This variable has reasonable validity against the overall sleep quality of the Pittsburgh Sleep Quality Index [25] as an acknowledged reference measurement. The Spearman’s rank correlation coefficients were 0.89 and 0.64 for overall sleep quality (0, 1, 2; p < 0.0001) in the elderly (n = 35) and young adults (n = 42), respectively (data not shown).
Food and Nutrient Intakes
MATERIALS AND METHODS Study Population We used the representative Elderly Nutrition and Health Survey in Taiwan (NAHSIT) performed during 1999–2000 [24]. A total of 1901 subjects aged 65 years or older completed the faceto-face interview and were linked to the National Death Registry after excluding 36 subjects who did not have a valid Identification Number. Three subjects were incorrectly recorded and 33 subjects did not have sleep information. This left 1865 subjects who were eligible for analysis. All information was collected by face-to-face household interviews and mobile health examinations. Data collected included household and demographic information, a 24-hour dietary recall, a simplified food frequency questionnaire (FFQ), eating habits, medical history, and sleep status. All participants signed informed consent. The ethics committees of both Academia Sinica and the National Health Research Institutes in Taiwan approved the study protocol.
Sleep Quality Assessment and Validity Self-reported sleep status was derived from answers to the following nine questions: 1. How long does it take to fall asleep? 2. In the past 3 months, how many nights per week did you not get enough sleep? 3. In the past 3 months, how many nights per week could you not sleep? 4. In the past 3 months, did you feel that there was interference with your sleep over one week? 5. In the past 3 months, how frequently were you awake after falling asleep over one week? 6. Do you feel tired when you are awake? 7. In the past 3 months, what would be the frequency of awakening early?
418
Dietary information was collected by a 24-hour dietary recall and FFQ. The 24-hour dietary recall and nutrient computation methodology were the same as those used in NAHSIT 1993– 1996 [26]. The daily servings of each food item were based on the combined 24-hour dietary and FFQ information. The 24-hour dietary information was used to calculate the genderspecific servings of food intake by each food group. The dietary diversity score (DDS) was derived from 6 aspects of dietary intake: grains, dairy, egg/soy/meat/fish, vegetables, fruits, and oil [27]. The cutoff point for an acceptable DDS was ≤4 and >4. The frequencies of food intake, including fruit juice, coffee, tea, and sugary drinks, were determined from the FFQ.
Biomarker Measurement The physical examination was carried out in the morning and subjects fasted overnight for a minimum of 8 hours. Erythrocyte transketolase, glutathione reductase, plasma pryridoxal phosphate (PLP), plasma folate, and serum vitamin B-12 were measured to evaluate the long-term nutritional status of thiamin, riboflavin, B-6, folate, and vitamin B-12, respectively. We classified erythrocyte transketolase (3 days In the past 3 months, did you feel that there was interference with your sleep over one week? No 1–2 days >3 days In the past 3 months, how frequently were you awake after falling asleep over one week? No occasions 1–2 days >3 days Do you feel tired when you are awake? No A little Very tired In the past 3 months, what would be the frequency of awakening early? None 1–2 days >3 days Have you used sleeping pills at all in the past 3 months? No Sometimes At least once per week a
38.8
47.6
13.7
23.2
51.4
25.4
ISSN: 0731-5724 (Print) 1541-1087 (Online) Journal homepage: http://www.tandfonline.com/loi/uacn20
Sleep Quality in the Survival of Elderly Taiwanese: Roles for Dietary Diversity and Pyridoxine in Men and Women Yi-Chen Huang MPH , Mark L. Wahlqvist MD & Meei-Shyuan Lee DrPH To cite this article: Yi-Chen Huang MPH , Mark L. Wahlqvist MD & Meei-Shyuan Lee DrPH (2013) Sleep Quality in the Survival of Elderly Taiwanese: Roles for Dietary Diversity and Pyridoxine in Men and Women, Journal of the American College of Nutrition, 32:6, 417-427, DOI: 10.1080/07315724.2013.848158 To link to this article: http://dx.doi.org/10.1080/07315724.2013.848158
Published online: 10 Dec 2013.
Submit your article to this journal
Article views: 144
View related articles
Full Terms & Conditions of access and use can be found at http://www.tandfonline.com/action/journalInformation?journalCode=uacn20 Download by: [Inter-American Development Bank (KNL/FHL)]
Date: 05 November 2015, At: 19:26
Sleep Quality in the Survival of Elderly Taiwanese: Roles for Dietary Diversity and Pyridoxine in Men and Women
Downloaded by [Inter-American Development Bank (KNL/FHL)] at 19:26 05 November 2015
Yi-Chen Huang, MPH, Mark L. Wahlqvist, MD, Meei-Shyuan Lee, DrPH Graduate Institute of Life Sciences, National Defense Medical Center, Taipei (Y.-C.H., M.-S.L.), Institute of Population Health Sciences, National Health Research Institutes, Taiwan, REPUBLIC OF CHINA (M.L.W.), Department of Epidemiology and Preventive Medicine and the Monash Asia Institute, Monash University, Melbourne, AUSTRALIA (M.L.W.), School of Public Health, National Defense Medical Center, Taiwan, REPUBLIC OF CHINA (M.L.W., M.-S.L.), Monash Asia Institute, Monash University, Caulfield East, Victoria, AUSTRALIA (M.L.W., M.-S.L.) Key words: vitamin B-6, DDS, sleep, gender, mortality Objectives: The purpose of this study was to investigate dietary contributors to relationships between sleep and all-cause mortality among elderly men and women using a prospective cohort study. Setting: The representative Nutrition and Health Survey in Taiwan (NAHSIT) for elders during 1999–2000. Subjects: One thousand eight hundred sixty-five individuals aged ≥65 years from NAHSIT (942 men and 923 women). Measures of Outcome: Dietary diversity scores (DDS) were from 24-hour dietary recalls. Participants were examined and fasting blood was taken. Sleep quality was assessed by questionnaire and classified as poor, fair, or good. Death registry linkage was made until December 31, 2008. Results: For women, poor sleepers had significantly lower vegetable and vitamin B-6 intakes compared to good sleepers (p < 0.05). For men, good and fair sleepers had a lower risk of death compared to poor sleepers after adjustment with hazards ratios (HRs) and 95% confidence intervals (CIs) of 0.60 (0.42–0.87) and 0.55 (0.36–0.86). The joint HRs for “DDS > 4 and good sleep” were 0.38 (0.22–0.66) for men and 0.52 (0.30–0.88) for women compared to “DDS ≤ 4 and poor sleep.” The joint HRs for “plasma pyridoxal phosphate (PLP) adequate and fair sleep” were 0.27 (0.11–0.65) and 0.49 (0.23–1.07) compared to “insufficient and poor sleep” for men and women; for women, PLP adequacy provided significantly reduced HRs for good and poor sleep. Conclusions: Sleep quality played a more important role in mortality for men than for women. Sufficient dietary diversity in men could offset the adverse effect on mortality of poor sleep. In women, PLP predicts mortality more than sleep does.
INTRODUCTION
munities have reported at least one chronic sleep complaint [5], which may have been quantitative or qualitative. Sleep quality is related to sociodemographic variables such as education and marital status; to health-related behaviors such as work hours, smoking, and alcohol consumption; to physical (obesity and related disorders) and mental (depression) health [6,7]; and to physical performance [8]. In addition, some studies have shown that women have more sleep problems than men [9–11]. Both short and long sleep durations are associated with increased morbidity and mortality [12–14], including obesity [15], diabetes [16], metabolic syndrome [17], cardiovascular disease
Sleep, diet, and nutrition rank highly in populist health culture, with as many as 182 million listings on the Google Internet search engine in 2011. However, this is not matched by the scientific literature, for which there are few studies. Those studies that are available have principally to do with the effect of sleep deprivation on energy expenditure [1] and intake [2,3] and their consequences for obesity [4]. Yet quality and quantity of life are dependent on sleep, and this becomes a particular problem with age. Over one half of the elderly in U.S. com-
Address correspondence to: Professor Meei-Shyuan Lee, School of Public Health, National Defense Medical Center, 161 Minchuan East Road, Sec. 6, Taipei, Taiwan 114, REPUBLIC OF CHINA. E-mail: [email protected] National Health Research Institutes, the funder of the study, had no role in the study design, data collection, data analysis, data interpretation, or writing of the report. All authors had access to the data and agreed to submit for publication. Abbreviations: ANOVA = analysis of variance, BMI = body mass index, CI = confidence intervals, DDS = dietary diversity score, EGRAC = glutathione reductase, ETKAC = erythrocyte transketolase, FFQ = food frequency questionnaire, HR = hazard ratio, METs = metabolic equivalents, NAHSIT = Nutrition and Health Survey in Taiwan, PLP = plasma pyridoxal phosphate, SF-36 = International Quality of Life Assessment 36-item Short Form.
Journal of the American College of Nutrition, Vol. 32, No. 6, 417–427 (2013) C American College of Nutrition Published by Taylor & Francis Group, LLC 417
Downloaded by [Inter-American Development Bank (KNL/FHL)] at 19:26 05 November 2015
Sleep, Dietary Quality, and Survival in Elders [18,19], and coronary heart disease [20]. Short sleep duration decreases leptin and increases ghrelin with increases in appetite [21] and food intake [2,3] and reduction in energy expenditure [1]. Taiwanese adolescents who have adequate sleep have a higher frequency of health-promoting behaviors such as a healthy diet, appreciation for life, responsibility for health, and exercise [22]. Intervention focusing on education on healthy dietary practices in elderly people has been associated with a modest increase in sleep duration and more stable indices of health [23]. There are few studies that have explored gender differences and diet quality in regard to sleep and mortality. We have studied these relationships and considered whether gender and diet-associated sleep patterns predict survival during a 10-year follow-up of an elderly Taiwanese population.
8. Have you used sleeping pills at all in the past 3 months? 9. How would you rate your overall sleep quality in the past 3 months?
The present study used the ninth question about overall sleep quality to categorize the sleep status of subjects as poor, fair, or good, because it was highly correlated with each of the other 8 questions (Table 1). This variable has reasonable validity against the overall sleep quality of the Pittsburgh Sleep Quality Index [25] as an acknowledged reference measurement. The Spearman’s rank correlation coefficients were 0.89 and 0.64 for overall sleep quality (0, 1, 2; p < 0.0001) in the elderly (n = 35) and young adults (n = 42), respectively (data not shown).
Food and Nutrient Intakes
MATERIALS AND METHODS Study Population We used the representative Elderly Nutrition and Health Survey in Taiwan (NAHSIT) performed during 1999–2000 [24]. A total of 1901 subjects aged 65 years or older completed the faceto-face interview and were linked to the National Death Registry after excluding 36 subjects who did not have a valid Identification Number. Three subjects were incorrectly recorded and 33 subjects did not have sleep information. This left 1865 subjects who were eligible for analysis. All information was collected by face-to-face household interviews and mobile health examinations. Data collected included household and demographic information, a 24-hour dietary recall, a simplified food frequency questionnaire (FFQ), eating habits, medical history, and sleep status. All participants signed informed consent. The ethics committees of both Academia Sinica and the National Health Research Institutes in Taiwan approved the study protocol.
Sleep Quality Assessment and Validity Self-reported sleep status was derived from answers to the following nine questions: 1. How long does it take to fall asleep? 2. In the past 3 months, how many nights per week did you not get enough sleep? 3. In the past 3 months, how many nights per week could you not sleep? 4. In the past 3 months, did you feel that there was interference with your sleep over one week? 5. In the past 3 months, how frequently were you awake after falling asleep over one week? 6. Do you feel tired when you are awake? 7. In the past 3 months, what would be the frequency of awakening early?
418
Dietary information was collected by a 24-hour dietary recall and FFQ. The 24-hour dietary recall and nutrient computation methodology were the same as those used in NAHSIT 1993– 1996 [26]. The daily servings of each food item were based on the combined 24-hour dietary and FFQ information. The 24-hour dietary information was used to calculate the genderspecific servings of food intake by each food group. The dietary diversity score (DDS) was derived from 6 aspects of dietary intake: grains, dairy, egg/soy/meat/fish, vegetables, fruits, and oil [27]. The cutoff point for an acceptable DDS was ≤4 and >4. The frequencies of food intake, including fruit juice, coffee, tea, and sugary drinks, were determined from the FFQ.
Biomarker Measurement The physical examination was carried out in the morning and subjects fasted overnight for a minimum of 8 hours. Erythrocyte transketolase, glutathione reductase, plasma pryridoxal phosphate (PLP), plasma folate, and serum vitamin B-12 were measured to evaluate the long-term nutritional status of thiamin, riboflavin, B-6, folate, and vitamin B-12, respectively. We classified erythrocyte transketolase (3 days In the past 3 months, did you feel that there was interference with your sleep over one week? No 1–2 days >3 days In the past 3 months, how frequently were you awake after falling asleep over one week? No occasions 1–2 days >3 days Do you feel tired when you are awake? No A little Very tired In the past 3 months, what would be the frequency of awakening early? None 1–2 days >3 days Have you used sleeping pills at all in the past 3 months? No Sometimes At least once per week a
38.8
47.6
13.7
23.2
51.4
25.4
